The blocking reagent optimization for the magnetoelastic biosensor

NASA Astrophysics Data System (ADS)

Hu, Jiajia; Chai, Yating; Horikawa, Shin; Wikle, Howard C.; Wang, Feng'en; Du, Songtao; Chin, Bryan A.; Hu, Jing

2015-06-01

The wireless phage-based magnetoelastic (ME) biosensor has proven to be promising for real-time detection of pathogenic bacteria on fresh produces. The ME biosensor consists of a freestanding ME resonator as the signal transducer and filamentous phage as the biomolecular-recognition element, which can specifically bind to a pathogen of interest. Due to the Joule magnetostriction effect, the biosensors can be placed into mechanical resonance when subjected to a time-varying magnetic field alternating at the sensor's resonant frequency. Upon the attachment of the target pathogen, the mass of the biosensor increases, thereby decreasing its resonant frequency. This paper presents an investigation of blocking reagents immobilization for detecting Salmonella Typhimurium on fresh food surfaces. Three different blocking reagents (BSA, SuperBlock blocking buffer, and blocker BLOTTO) were used and compared. The optical microscope was used for bacterial cells binding observation. Student t-test was used to statistically analysis the experiment results. The results shows that SuperBlock blocking buffer and blocker BLOTTO have much better blocking performance than usually used BSA.

Effects of riparian buffers on hydrology of northern seasonal ponds

Treesearch

Randall K. Kolka; Brian J. Palik; Daniel P. Tersteeg; James C. Bell

2011-01-01

Although seasonal ponds are common in northern, glaciated, forested landscapes, forest management guidelines are generally lacking for these systems. The objective of this study was to determine the effect of riparian buffer type on seasonal pond hydrology following harvest of the adjacent upland forest. A replicated block design consisting of four buffer treatments...

Inhibition of protein carbamylation in urea solution using ammonium-containing buffers.

PubMed

Sun, Shisheng; Zhou, Jian-Ying; Yang, Weiming; Zhang, Hui

2014-02-01

Urea solution is one of the most commonly employed protein denaturants for protease digestion in proteomic studies. However, it has long been recognized that urea solution can cause carbamylation at the N termini of proteins/peptides and at the side chain amino groups of lysine and arginine residues. Protein/peptide carbamylation blocks protease digestion and affects protein identification and quantification in mass spectrometry analysis by blocking peptide amino groups from isotopic/isobaric labeling and changing peptide charge states, retention times, and masses. In addition, protein carbamylation during sample preparation makes it difficult to study in vivo protein carbamylation. In this study, we compared the peptide carbamylation in urea solutions of different buffers and found that ammonium-containing buffers were the most effective buffers to inhibit protein carbamylation in urea solution. The possible mechanism of carbamylation inhibition by ammonium-containing buffers is discussed, and a revised procedure for the protease digestion of proteins in urea and ammonium-containing buffers was developed to facilitate its application in proteomic research. Copyright © 2013 Elsevier Inc. All rights reserved.

Toward Composable Hardware Agnostic Communications Blocks Lessons Learned

DTIC Science & Technology

2016-11-01

ad9361/products/product.html [12] Google. Protocol Buffers. [Online]. Available: https://developers.google.com/protocol-buffers/ [13] VITA, “ANSI/VITA 49.0 VITA Radio Transport ( VRT ) Standard,” VITA, Tech. Rep., 2015.

Identification of Cytoplasmic Proteins Interacting with the Mammary Cell Transforming Domain of Ese-1

DTIC Science & Technology

2008-04-01

antibody:blocking buffer overnight at 4°C in a moisture chamber. To measure auto - fluorescence , cells were incubated overnight at 4°C with blocking buffer...as a monomer and are auto -inhibited by virtue of two inhibitory regions that flank the DBD. Disinhibition, resulting in enhancement of ETS DBD...placenta, lung, kidney, prostate, intestine, breast, skin, retina and other epithelia (7-10). During mouse embryo development, Elf3 mRNA expression

Improved fill factor in inverted planar perovskite solar cells with zirconium acetate as the hole-and-ion-blocking layer.

PubMed

Zhang, Xuewen; Liang, Chunjun; Sun, Mengjie; Zhang, Huimin; Ji, Chao; Guo, Zebang; Xu, Yajun; Sun, Fulin; Song, Qi; He, Zhiqun

2018-03-14

Planar perovskite solar cells (PSCs) have gained great interest due to their low-temperature solution preparation and simple process. In inverted planar PSCs, an additional buffer layer is usually needed on the top of the PCBM electron-transport layer (ETL) to enhance the device performance. In this work, we used a new buffer layer, zirconium acetate (Zr(Ac) 4 ). The inclusion of the Zr(Ac) 4 buffer layer leads to the increase of FF from ∼68% to ∼79% and PCE from ∼14% to ∼17% in the planar PSCs. The UPS measurement indicates that the Zr(Ac) 4 layer has a low HOMO level of -8.2 eV, indicating that the buffer layer can act as a hole-blocking layer. Surface morphology and surface chemistry investigations reveal that the elements I, MA and Pb can diffuse across the PCBM ETL, damaging the device performance. The covering Zr(Ac) 4 molecules fill in the pinholes of the PCBM layer and effectively block the ions/molecules of the perovskite from diffusion across the ETL. The resulting more robust PCBM/Zr(Ac) 4 ETL leads to weaker ionic charge accumulation and lower diode leakage current. The double role of hole-and-ion blocking of the Zr(Ac) 4 layer explains the improved FF and PCE in the PSCs.

Buffer management to solve bed-blocking in the Netherlands 2000–2010. Cooperation from an integrated care chain perspective as a key success factor for managing patient flows

PubMed Central

Mur-Veeman, Ingrid; Govers, Mark

2011-01-01

Introduction Bed-blocking problems in hospitals reflect how difficult and complex it is to move patients smoothly through the chain of care. In the Netherlands, during the first decade of the 21st century, some hospitals attempted to tackle this problem by using an Intermediate Care Department (ICD) as a buffer for bed-blockers. However, research has shown that ICDs do not sufficiently solve the bed-blocking problem and that bed-blocking is often caused by a lack of buffer management. Tool Buffer management (BM) is a tool that endeavors to balance patient flow in the hospital to nursing home chain of care. Results Additional research has indicated that the absence of BM is not the result of providers’ thinking that BM is unnecessary, unethical or impossible because of unpredictable patient flows. Instead, BM is hampered by a lack of cooperation between care providers. Conclusion Although stakeholders recognize that cooperation is imperative, they often fail to take the actions necessary to realize cooperation. Our assumption is that this lack of willingness and ability to cooperate is the result of several impeding conditions as well as stakeholders’ perceptions of these conditions and the persistence of their current routines, principles and beliefs (RPBs). Discussion We recommend simultaneously working on improving the conditions and changing stakeholders’ perceptions and RPBs. PMID:21954373

Stream water responses to timber harvest: Riparian buffer width effectiveness

Treesearch

Barton D. Clinton

2011-01-01

Vegetated riparian buffers are critical for protecting aquatic and terrestrial processes and habitats in southern Appalachian ecosystems. In this case study, we examined the effect of riparian buffer width on stream water quality following upland forest management activities in four headwater catchments. Three riparian buffer widths were delineated prior to cutting; 0m...

Buffer Zone Sign Template

EPA Pesticide Factsheets

The certified pesticide applicator is required to post a comparable sign, designating a buffer zone around the soil fumigant application block in order to control exposure risk. It must include the don't walk symbol, product name, and applicator contact.

Calculating Buffer Zones: A Guide for Applicators

EPA Pesticide Factsheets

Buffer zones provide distance between the application block (i.e., edge of the treated field) and bystanders, in order to control pesticide exposure risk from soil fumigants. Distance requirements may be reduced by credits such as tarps.

Protein extraction from methanol fixed paraffin embedded tissue blocks: A new possibility using cell blocks

PubMed Central

Kokkat, Theresa J.; McGarvey, Diane; Patel, Miral S.; Tieniber, Andrew D.; LiVolsi, Virginia A.; Baloch, Zubair W.

2013-01-01

Background: Methanol fixed and paraffin embedded (MFPE) cellblocks are an essential cytology preparation. However, MFPE cellblocks often contain limited material and their relatively small size has caused them to be overlooked in biomarker discovery. Advances in the field of molecular biotechnology have made it possible to extract proteins from formalin fixed and paraffin embedded (FFPE) tissue blocks. In contrast, there are no established methods for extracting proteins from MFPE cellblocks. We investigated commonly available CHAPS (3-[(3-cholamidopropyl) dimethylammonio]-1-propanesulfonate) buffer, as well as two commercially available Qiagen® kits and compared their effectiveness on MFPE tissue for protein yields. Materials and Methods: MFPE blocks were made by Cellient™ automated system using human tissue specimens from normal and malignant specimens collected in ThinPrep™ Vials. Protein was extracted from Cellient-methanol fixed and paraffin embedded blocks with CHAPS buffer method as well as FFPE and Mammalian Qiagen® kits. Results: Comparison of protein yields demonstrated the effectiveness of various protein extraction methods on MFPE cellblocks. Conclusion: In the current era of minimally invasive techniques to obtain minimal amount of tissue for diagnostic and prognostic purposes, the use of commercial and lab made buffer on low weight MFPE scrapings obtained by Cellient® processor opens new possibilities for protein biomarker research. PMID:24403950

Buffered Lidocaine With Sodium Bicarbonate did not Increase Inferior Alveolar Nerve Block Success Rate in Patients Having Symptomatic Irreversible Pulpitis.

PubMed

Parirokh, Masoud

2016-03-01

Effect of buffered 4% lidocaine on the success of the inferior alveolar nerve block in patients with symptomatic irreversible pulpitis: a prospective, randomized, double-blind study. Schellenberg J, Drum M, Reader A, Nusstein J, Fowler S, Beck M. J Endod 2015;41(6):791-6. The study was supported by Meyers/Reader Graduate Endodontic Support Fund Double blinded randomized controlled trial. Copyright © 2016 Elsevier Inc. All rights reserved.

EDITSPEC: System Manual. Volume IV. Data Handler.

DTIC Science & Technology

1980-11-01

PRINTS AND ABORTS OR RETURNS WITHOUT SAYING ANYTHING DKFBF FILL BUFFER ROUTINE: BT ENTRY AT IBTAD IS IN D GET BLOCK NBL OF DATA SET NSW IN AND WAIT FOR...READ COMPLETION DKFND ROUTINE TO LOCATE BLOCK NBL SEGMENT NSG OF DATA SET NSW. N SEARCHES BT’S FIRST’THEN READS INTO CORE RETURNS IBTAD=THE BT ENTRY...WHICH IS RETURNED IN NBL . DKMIC ROUTINE TO SEARCH IN CORE BUFFER TABLES FOR ONE WITH DATA SET NOS FILENAME FILNM AND RETURN THE ONE WITH THE MOST

Performance Enhancement of Small Molecular Solar Cells by Bilayer Cathode Buffer.

PubMed

Sun, Qinjun; Zhao, Huanbin; Zhou, Miao; Gao, Liyan; Hao, Yuying

2016-04-01

An effective composite bilayer cathode buffer structure is proposed for use in small molecular solar cells. CsF was doped in Alq3 to form the first cathode buffer, leading to small serial resistances. BCP was used as the second cathode buffer to block the holes to the electrode. The optimized bilayer cathode buffer significantly increased the short circuit and fill factor of devices. By integrating this bilayer cathode buffer, the CuPc/C60 small molecular heterojunction cell exhibited a power conversion efficiency of up to 0.8%, which was an improvement of 56% compared to a device with only the Alq3 cathode buffer. Meanwhile, the bilayer cathode buffer still has a good protective effect on the performance of the device.

Proton-Mediated Block of Ca2+ Channels during Multivesicular Release Regulates Short-Term Plasticity at an Auditory Hair Cell Synapse

PubMed Central

Cho, Soyoun

2014-01-01

Synaptic vesicles release both neurotransmitter and protons during exocytosis, which may result in a transient acidification of the synaptic cleft that can block Ca2+ channels located close to the sites of exocytosis. Evidence for this effect has been reported for retinal ribbon-type synapses, but not for hair cell ribbon synapses. Here, we report evidence for proton release from bullfrog auditory hair cells when they are held at more physiological, in vivo–like holding potentials (Vh = −60 mV) that facilitate multivesicular release. During paired recordings of hair cells and afferent fibers, L-type voltage-gated Ca2+ currents showed a transient block, which was highly correlated with the EPSC amplitude (or the amount of glutamate release). This effect was masked at Vh = −90 mV due to the presence of a T-type Ca2+ current and blocked by strong pH buffering with HEPES or TABS. Increasing vesicular pH with internal methylamine in hair cells also abolished the transient block. High concentrations of intracellular Ca2+ buffer (10 mm BAPTA) greatly reduced exocytosis and abolished the transient block of the Ca2+ current. We estimate that this transient block is due to the rapid multivesicular release of ∼600–1300 H+ ions per synaptic ribbon. Finally, during a train of depolarizing pulses, paired pulse plasticity was significantly changed by using 40 mm HEPES in addition to bicarbonate buffer. We propose that this transient block of Ca2+ current leads to more efficient exocytosis per Ca2+ ion influx and it may contribute to spike adaptation at the auditory nerve. PMID:25429130

The StreamCat Dataset: Accumulated Attributes for NHDPlusV2 (Version 2.1) Catchments Riparian Buffer for the Conterminous United States: 2010 US Census Housing Unit and Population Density

EPA Pesticide Factsheets

This dataset represents the population and housing unit density within individual, local NHDPlusV2 catchments and upstream, contributing watersheds riparian buffers based on 2010 US Census data. Densities are calculated for every block group and watershed averages are calculated for every local NHDPlusV2 catchment(see Data Sources for links to NHDPlusV2 data and Census Data). This data set is derived from The TIGER/Line Files and related database (.dbf) files for the conterminous USA. It was downloaded as Block Group-Level Census 2010 SF1 Data in File Geodatabase Format (ArcGIS version 10.0). The landscape raster (LR) was produced based on the data compiled from the questions asked of all people and about every housing unit. The (block-group population / block group area) and (block-group housing units / block group area) were summarized by local catchment and by watershed to produce local catchment-level and watershed-level metrics as a continuous data type (see Data Structure and Attribute Information for a description).

Software Defined Radio with Parallelized Software Architecture

NASA Technical Reports Server (NTRS)

Heckler, Greg

2013-01-01

This software implements software-defined radio procession over multicore, multi-CPU systems in a way that maximizes the use of CPU resources in the system. The software treats each processing step in either a communications or navigation modulator or demodulator system as an independent, threaded block. Each threaded block is defined with a programmable number of input or output buffers; these buffers are implemented using POSIX pipes. In addition, each threaded block is assigned a unique thread upon block installation. A modulator or demodulator system is built by assembly of the threaded blocks into a flow graph, which assembles the processing blocks to accomplish the desired signal processing. This software architecture allows the software to scale effortlessly between single CPU/single-core computers or multi-CPU/multi-core computers without recompilation. NASA spaceflight and ground communications systems currently rely exclusively on ASICs or FPGAs. This software allows low- and medium-bandwidth (100 bps to approx.50 Mbps) software defined radios to be designed and implemented solely in C/C++ software, while lowering development costs and facilitating reuse and extensibility.

Software Defined Radio with Parallelized Software Architecture

NASA Technical Reports Server (NTRS)

Heckler, Greg

2013-01-01

This software implements software-defined radio procession over multi-core, multi-CPU systems in a way that maximizes the use of CPU resources in the system. The software treats each processing step in either a communications or navigation modulator or demodulator system as an independent, threaded block. Each threaded block is defined with a programmable number of input or output buffers; these buffers are implemented using POSIX pipes. In addition, each threaded block is assigned a unique thread upon block installation. A modulator or demodulator system is built by assembly of the threaded blocks into a flow graph, which assembles the processing blocks to accomplish the desired signal processing. This software architecture allows the software to scale effortlessly between single CPU/single-core computers or multi-CPU/multi-core computers without recompilation. NASA spaceflight and ground communications systems currently rely exclusively on ASICs or FPGAs. This software allows low- and medium-bandwidth (100 bps to .50 Mbps) software defined radios to be designed and implemented solely in C/C++ software, while lowering development costs and facilitating reuse and extensibility.

Optimization of ELISA Conditions to Quantify Colorectal Cancer Antigen-Antibody Complex Protein (GA733-FcK) Expressed in Transgenic Plant

PubMed Central

Ahn, Junsik; Lee, Kyung Jin

2014-01-01

The purpose of this study is to optimize ELISA conditions to quantify the colorectal cancer antigen GA733 linked to the Fc antibody fragment fused to KDEL, an ER retention motif (GA733-FcK) expressed in transgenic plant. Variable conditions of capture antibody, blocking buffer, and detection antibody for ELISA were optimized with application of leaf extracts from transgenic plant expressing GA733-FcK. In detection antibody, anti-EpCAM/CD362 IgG recognizing the GA733 did not detect any GA733-FcK whereas anti-human Fc IgG recognizing the human Fc existed in plant leaf extracts. For blocking buffer conditions, 3% BSA buffer clearly blocked the plate, compared to the 5% skim-milk buffer. For capture antibody, monoclonal antibody (MAb) CO17-1A was applied to coat the plate with different amounts (1, 0.5, and 0.25 μg/well). Among the amounts of the capture antibody, 1 and 0.5 μg/well (capture antibody) showed similar absorbance, whereas 0.25 μg/well of the capture antibody showed significantly less absorbance. Taken together, the optimized conditions to quantify plant-derived GA733-FcK were 0.5 μg/well of MAb CO17-1A per well for the capture antibody, 3% BSA for blocking buffer, and anti-human Fc conjugated HRP. To confirm the optimized ELISA conditions, correlation analysis was conducted between the quantified amount of GA733-FcK in ELISA and its protein density values of different leaf samples in Western blot. The co-efficient value R2 between the ELISA quantified value and protein density was 0.85 (p<0.01), which indicates that the optimized ELISA conditions feasibly provides quantitative information of GA733-FcK expression in transgenic plant. PMID:24555929

Body Buffer Zone and Proxemics in Blocking.

ERIC Educational Resources Information Center

Stockwell, John C.; Bahs, Clarence W.

This paper investigates the effect of personal body buffer zones on compositional arrangements staged by novice directors. Relationships between directors' concepts of personal space and their projection of its dimensions into staging are studied through the use of a variety of proximity measures--distance, area angles of approach, and physical…

Effects of degraded sensory input on memory for speech: behavioral data and a test of biologically constrained computational models.

PubMed

Piquado, Tepring; Cousins, Katheryn A Q; Wingfield, Arthur; Miller, Paul

2010-12-13

Poor hearing acuity reduces memory for spoken words, even when the words are presented with enough clarity for correct recognition. An "effortful hypothesis" suggests that the perceptual effort needed for recognition draws from resources that would otherwise be available for encoding the word in memory. To assess this hypothesis, we conducted a behavioral task requiring immediate free recall of word-lists, some of which contained an acoustically masked word that was just above perceptual threshold. Results show that masking a word reduces the recall of that word and words prior to it, as well as weakening the linking associations between the masked and prior words. In contrast, recall probabilities of words following the masked word are not affected. To account for this effect we conducted computational simulations testing two classes of models: Associative Linking Models and Short-Term Memory Buffer Models. Only a model that integrated both contextual linking and buffer components matched all of the effects of masking observed in our behavioral data. In this Linking-Buffer Model, the masked word disrupts a short-term memory buffer, causing associative links of words in the buffer to be weakened, affecting memory for the masked word and the word prior to it, while allowing links of words following the masked word to be spared. We suggest that these data account for the so-called "effortful hypothesis", where distorted input has a detrimental impact on prior information stored in short-term memory. Copyright © 2010 Elsevier B.V. All rights reserved.

Reduction of shunt current in buffer-free IrMn based spin-valve structures

NASA Astrophysics Data System (ADS)

Kocaman, B.; Akdoğan, N.

2018-06-01

The presence of thick buffer layers in magnetic sensor devices decreases sensor sensitivity due to shunt currents. With this motivation, we produced IrMn-based spin-valve multilayers without using buffer layer. We also studied the effects of post-annealing and IrMn thickness on exchange bias field (HEB) and blocking temperature (TB) of the system. Magnetization measurements indicate that both HEB and TB values are significantly enhanced with post-annealing of IrMn layer. In addition, we report that IrMn thickness of the system strongly influences the magnetization and transport characteristics of the spin-valve structures. We found that the minimum thickness of IrMn layer is 6 nm in order to achieve the lowest shunt current and high blocking temperature (>300 K). We also investigated the training of exchange bias to check the long-term durability of IrMn-based spin-valve structures for device applications.

A Prospective, Randomized, Double-Blind Study of the Anesthetic Efficacy of Sodium Bicarbonate Buffered 2% Lidocaine With 1 : 100,000 Epinephrine in Inferior Alveolar Nerve Blocks

PubMed Central

Whitcomb, Michael; Drum, Melissa; Reader, Al; Nusstein, John; Beck, Mike

2010-01-01

Abstract The authors, using a crossover design, randomly administered, in a double-blind manner, inferior alveolar nerve (IAN) blocks using a buffered 2% lidocaine with 1 : 100,000 epinephrine/sodium bicarbonate formulation and an unbuffered 2% lidocaine with 1 : 100,000 epinephrine formulation at 2 separate appointments spaced at least 1 week apart. An electric pulp tester was used in 4-minute cycles for 60 minutes to test for anesthesia of the first and second molars, premolars, and lateral and central incisors. Anesthesia was considered successful when 2 consecutive 80 readings were obtained within 15 minutes, and the 80 reading was continuously sustained for 60 minutes. For the buffered 2% lidocaine with 1 : 100,000 epinephrine/sodium bicarbonate formulation, successful pulpal anesthesia ranged from 10–71%. For the unbuffered 2% lidocaine with 1 : 100,000 epinephrine formulation, successful pulpal anesthesia ranged from 10–72%. No significant differences between the 2 anesthetic formulations were noted. The buffered lidocaine formulation did not statistically result in faster onset of pulpal anesthesia or less pain during injection than did the unbuffered lidocaine formulation. We concluded that buffering a 2% lidocaine with 1 : 100,000 epinephrine with sodium bicarbonate, as was formulated in the current study, did not statistically increase anesthetic success, provide faster onset, or result in less pain of injection when compared with unbuffered 2% lidocaine with 1 : 100,000 epinephrine for an IAN block. PMID:20553136

Distributed metadata in a high performance computing environment

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

Bent, John M.; Faibish, Sorin; Zhang, Zhenhua

A computer-executable method, system, and computer program product for managing meta-data in a distributed storage system, wherein the distributed storage system includes one or more burst buffers enabled to operate with a distributed key-value store, the co computer-executable method, system, and computer program product comprising receiving a request for meta-data associated with a block of data stored in a first burst buffer of the one or more burst buffers in the distributed storage system, wherein the meta data is associated with a key-value, determining which of the one or more burst buffers stores the requested metadata, and upon determination thatmore » a first burst buffer of the one or more burst buffers stores the requested metadata, locating the key-value in a portion of the distributed key-value store accessible from the first burst buffer.« less

Improving fatigue resistance of Pb(Zr,Ti)O3 thin films by using PbZrO3 buffer layers

NASA Astrophysics Data System (ADS)

Mensur Alkoy, Ebru; Uchiyama, Kiyoshi; Shiosaki, Tadashi; Alkoy, Sedat

2006-05-01

Ferroelectric Pb(Zr0.52Ti0.48)O3 (PZT) thin films with PbZrO3 (PZ) buffer layers were prepared on Pt(111)/Ti/SiO2/Si(100) substrates using a hybrid rf magnetron sputtering and sol-gel process. Texture of PZT films was found to depend on Pb content of PZ buffer layers. Buffered PZT films displayed comparable ferroelectric properties (2Pr=38-53 μC/cm2,2Ec=136-170 kV/cm) with unbuffered PZT. Asymmetric leakage current and fatigue behavior with superior fatigue resistance was observed in PZ buffered PZT compared to unbuffered films. PZ buffer layers were found to affect crystallization and texture of PZT, and act as a capacitive interface layer possibly blocking charge injection from electrodes.

Circuit Recognition of VLSI Layouts

DTIC Science & Technology

1989-09-01

from the ** ** input file contain information on each transitor . ** totaltransistors=O; while(((strcmp(buffer. "n")))=O) 1Ms(trcmp(buffer.tp"))-=O)) I... statistics and information on transistors ** ** inverters and passgates prior to entering level2 recognition.** fprintf (fo. "no more transistors.\

A wide bandwidth CCD buffer memory system

NASA Technical Reports Server (NTRS)

Siemens, K.; Wallace, R. W.; Robinson, C. R.

1978-01-01

A prototype system was implemented to demonstrate that CCD's can be applied advantageously to the problem of low power digital storage and particularly to the problem of interfacing widely varying data rates. CCD shift register memories (8K bit) were used to construct a feasibility model 128 K-bit buffer memory system. Serial data that can have rates between 150 kHz and 4.0 MHz can be stored in 4K-bit, randomly-accessible memory blocks. Peak power dissipation during a data transfer is less than 7 W, while idle power is approximately 5.4 W. The system features automatic data input synchronization with the recirculating CCD memory block start address. System expansion to accommodate parallel inputs or a greater number of memory blocks can be performed in a modular fashion. Since the control logic does not increase proportionally to increase in memory capacity, the power requirements per bit of storage can be reduced significantly in a larger system.

Mitigation of substrate defects in reflective reticles using sequential coating and annealing

DOEpatents

Mirkanimi, Paul B.

2002-01-01

A buffer-layer to minimize the size of defects on a reticle substrate prior to deposition of a reflective coating on the substrate. The buffer-layer is formed by either a multilayer deposited on the substrate or by a plurality of sequentially deposited and annealed coatings deposited on the substrate. The plurality of sequentially deposited and annealed coating may comprise multilayer and single layer coatings. The multilayer deposited and annealed buffer layer coatings may be of the same or different material than the reflecting coating thereafter deposited on the buffer-layer.

A two-stage monolithic buffer amplifier for 20 GHz satellite communication

NASA Technical Reports Server (NTRS)

Petersen, W. C.; Gupta, A. K.

1983-01-01

Design, fabrication, and test results of a two-stage GaAs monolithic buffer amplifier for 20 GHz satellite communication are described in this paper. A gain of 13 + or - 0.75 dB from 17.7 to 20.2 GHz was obtained from the 1.5 x 1.5 millimeter chip, which includes all necessary bias and dc blocking circuitry.

The Design and Implementation of a Read Prediction Buffer

DTIC Science & Technology

1992-12-01

City, State, and ZIP Code) 7b ADDRESS (City, State. and ZIP Code) 8a. NAME OF FUNDING /SPONSORING 8b. OFFICE SYMBOL 9 PROCUREMENT INSTRUMENT... 9 E. THESIS STRUCTURE.. . .... ............... 9 II. READ PREDICTION ALGORITHM AND BUFFER DESIGN 10 A. THE READ PREDICTION ALGORITHM...29 Figure 9 . Basic Multiplexer Cell .... .......... .. 30 Figure 10. Block Diagram Simulation Labels ......... 38 viii I. INTRODUCTION A

Effect of a New Local Anesthetic Buffering Device on Pain Reduction During Nerve Block lnjections

DTIC Science & Technology

2014-07-10

injection by pH buffering. Arch Emerg Med 1990;7:65-68. 15. Guyton AC, Hall JE. Textbook of medical physiology. 11th ed. St. Louis: Mosby;2006:383-387...2014. 26. Drake RL, Wayne V, Mitchell AWM. Gray’s anatomy for students. St. Louis: Mosby; 2005:21-25. 27. DiFelice M, Maller S, Hancock R

Inverted bulk-heterojunction organic solar cells with the transfer-printed anodes and low-temperature-processed ultrathin buffer layers

NASA Astrophysics Data System (ADS)

Itoh, Eiji; Sakai, Shota; Fukuda, Katsutoshi

2018-03-01

We studied the effects of a hole buffer layer [molybdenum oxide (MoO3) and natural copper oxide layer] and a low-temperature-processed electron buffer layer on the performance of inverted bulk-heterojunction organic solar cells in a device consisting of indium-tin oxide (ITO)/poly(ethylene imine) (PEI)/titanium oxide nanosheet (TiO-NS)/poly(3-hexylthiopnehe) (P3HT):phenyl-C61-butyric acid methylester (PCBM)/oxide/anode (Ag or Cu). The insertion of ultrathin TiO-NS (˜1 nm) and oxide hole buffer layers improved the open circuit voltage V OC, fill factor, and rectification properties owing to the effective hole blocking and electron transport properties of ultrathin TiO-NS, and to the enhanced work function difference between TiO-NS and the oxide hole buffer layer. The insertion of the TiO-NS contributed to the reduction in the potential barrier at the ITO/PEI/TiO-NS/active layer interface for electrons, and the insertion of the oxide hole buffer layer contributed to the reduction in the potential barrier for holes. The marked increase in the capacitance under positive biasing in the capacitance-voltage characteristics revealed that the combination of TiO-NS and MoO3 buffer layers contributes to the selective transport of electrons and holes, and blocks counter carriers at the active layer/oxide interface. The natural oxide layer of the copper electrode also acts as a hole buffer layer owing to the increase in the work function of the Cu surface in the inverted cells. The performance of the cell with evaporated MoO3 and Cu layers that were transfer-printed to the active layer was almost comparable to that of the cell with MoO3 and Ag layers directly evaporated onto the active layer. We also demonstrated comparable device performance in the cell with all-printed MoO3 and low-temperature-processed silver nanoparticles as an anode.

Enhanced adhesion for LIGA microfabrication by using a buffer layer

DOEpatents

Bajikar, Sateesh S.; De Carlo, Francesco; Song, Joshua J.

2004-01-27

The present invention is an improvement on the LIGA microfabrication process wherein a buffer layer is applied to the upper or working surface of a substrate prior to the placement of a resist onto the surface of the substrate. The buffer layer is made from an inert low-Z material (low atomic weight), a material that absorbs secondary X-rays emissions from the substrate that are generated from the substrate upon exposure to a primary X-rays source. Suitable materials for the buffer layer include polyamides and polyimide. The preferred polyimide is synthesized form pyromellitic anhydride and oxydianiline (PMDA-ODA).

Enhanced adhesion for LIGA microfabrication by using a buffer layer

DOEpatents

Bajikar, Sateesh S.; De Carlo, Francesco; Song, Joshua J.

2001-01-01

The present invention is an improvement on the LIGA microfabrication process wherein a buffer layer is applied to the upper or working surface of a substrate prior to the placement of a resist onto the surface of the substrate. The buffer layer is made from an inert low-Z material (low atomic weight), a material that absorbs secondary X-rays emissions from the substrate that are generated from the substrate upon exposure to a primary X-rays source. Suitable materials for the buffer layer include polyamides and polyimide. The preferred polyimide is synthesized form pyromellitic anhydride and oxydianiline (PMDA-ODA).

Mitigation of substrate defects in reticles using multilayer buffer layers

DOEpatents

Mirkarimi, Paul B.; Bajt, Sasa; Stearns, Daniel G.

2001-01-01

A multilayer film is used as a buffer layer to minimize the size of defects on a reticle substrate prior to deposition of a reflective coating on the substrate. The multilayer buffer layer deposited intermediate the reticle substrate and the reflective coating produces a smoothing of small particles and other defects on the reticle substrate. The reduction in defect size is controlled by surface relaxation during the buffer layer growth process and by the degree of intermixing and volume contraction of the materials at the multilayer interfaces. The buffer layers are deposited at near-normal incidence via a low particulate ion beam sputtering process. The growth surface of the buffer layer may also be heated by a secondary ion source to increase the degree of intermixing and improve the mitigation of defects.

Interactive communication channel

NASA Astrophysics Data System (ADS)

Chan, R. H.; Mann, M. R.; Ciarrocchi, J. A.

1985-10-01

Discussed is an interactive communications channel (ICC) for providing a digital computer with high-performance multi-channel interfaces. Sixteen full duplex channels can be serviced in the ICC with the sequence or scan pattern being programmable and dependent upon the number or channels and their speed. A channel buffer system is used for line interface, and character exchange. The channel buffer system is on a byte basis. The ICC performs frame start and frame end functions, bit stripping and bit stuffing. Data is stored in a memory in block format (256 bytes maximum) by a program control and the ICC maintains byte address information and a block byte count. Data exchange with a memory is made by cycle steals. Error detection is also provided for using a cyclic redundancy check technique.

Lossless compression algorithm for REBL direct-write e-beam lithography system

NASA Astrophysics Data System (ADS)

Cramer, George; Liu, Hsin-I.; Zakhor, Avideh

2010-03-01

Future lithography systems must produce microchips with smaller feature sizes, while maintaining throughputs comparable to those of today's optical lithography systems. This places stringent constraints on the effective data throughput of any maskless lithography system. In recent years, we have developed a datapath architecture for direct-write lithography systems, and have shown that compression plays a key role in reducing throughput requirements of such systems. Our approach integrates a low complexity hardware-based decoder with the writers, in order to decompress a compressed data layer in real time on the fly. In doing so, we have developed a spectrum of lossless compression algorithms for integrated circuit layout data to provide a tradeoff between compression efficiency and hardware complexity, the latest of which is Block Golomb Context Copy Coding (Block GC3). In this paper, we present a modified version of Block GC3 called Block RGC3, specifically tailored to the REBL direct-write E-beam lithography system. Two characteristic features of the REBL system are a rotary stage resulting in arbitrarily-rotated layout imagery, and E-beam corrections prior to writing the data, both of which present significant challenges to lossless compression algorithms. Together, these effects reduce the effectiveness of both the copy and predict compression methods within Block GC3. Similar to Block GC3, our newly proposed technique Block RGC3, divides the image into a grid of two-dimensional "blocks" of pixels, each of which copies from a specified location in a history buffer of recently-decoded pixels. However, in Block RGC3 the number of possible copy locations is significantly increased, so as to allow repetition to be discovered along any angle of orientation, rather than horizontal or vertical. Also, by copying smaller groups of pixels at a time, repetition in layout patterns is easier to find and take advantage of. As a side effect, this increases the total number of copy locations to transmit; this is combated with an extra region-growing step, which enforces spatial coherence among neighboring copy locations, thereby improving compression efficiency. We characterize the performance of Block RGC3 in terms of compression efficiency and encoding complexity on a number of rotated Metal 1, Poly, and Via layouts at various angles, and show that Block RGC3 provides higher compression efficiency than existing lossless compression algorithms, including JPEG-LS, ZIP, BZIP2, and Block GC3.

Managing internode data communications for an uninitialized process in a parallel computer

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

Archer, Charles J; Blocksome, Michael A; Miller, Douglas R

2014-05-20

A parallel computer includes nodes, each having main memory and a messaging unit (MU). Each MU includes computer memory, which in turn includes, MU message buffers. Each MU message buffer is associated with an uninitialized process on the compute node. In the parallel computer, managing internode data communications for an uninitialized process includes: receiving, by an MU of a compute node, one or more data communications messages in an MU message buffer associated with an uninitialized process on the compute node; determining, by an application agent, that the MU message buffer associated with the uninitialized process is full prior tomore » initialization of the uninitialized process; establishing, by the application agent, a temporary message buffer for the uninitialized process in main computer memory; and moving, by the application agent, data communications messages from the MU message buffer associated with the uninitialized process to the temporary message buffer in main computer memory.« less

Managing internode data communications for an uninitialized process in a parallel computer

DOEpatents

Archer, Charles J; Blocksome, Michael A; Miller, Douglas R; Parker, Jeffrey J; Ratterman, Joseph D; Smith, Brian E

2014-05-20

A parallel computer includes nodes, each having main memory and a messaging unit (MU). Each MU includes computer memory, which in turn includes, MU message buffers. Each MU message buffer is associated with an uninitialized process on the compute node. In the parallel computer, managing internode data communications for an uninitialized process includes: receiving, by an MU of a compute node, one or more data communications messages in an MU message buffer associated with an uninitialized process on the compute node; determining, by an application agent, that the MU message buffer associated with the uninitialized process is full prior to initialization of the uninitialized process; establishing, by the application agent, a temporary message buffer for the uninitialized process in main computer memory; and moving, by the application agent, data communications messages from the MU message buffer associated with the uninitialized process to the temporary message buffer in main computer memory.

Is Endotoxemia in Stable Hemodialysis Patients an Artefact? Limitations of the Limulus Amebocyte Lysate Assay and Role of (1→3)-β-D Glucan

PubMed Central

Zhang, Yonglong; Patidar, Ashish; Vilar, Enric; Finkelman, Malcolm; Farrington, Ken

2016-01-01

Background Elevated blood endotoxin levels are frequently reported in the dialysis population and are strongly linked with inflammation, a major predictor of mortality. Virtually all studies have employed the Limulus Amoebocyte Lysate (LAL) assay to detect endotoxin. However this assay is not endotoxin-specific and can be activated by (1→3)-β-glucan (BG), a component of fungal cell walls leading to false positive signals. Very few studies have taken account of this. We examined the influence of BG-based activation of the LAL assay on the detection of endotoxemia in this setting. Method We measured plasma endotoxin levels in 50 hemodialysis patients with and without the use of BG-blocking buffers. These buffers inhibit BG activation of the LAL assay to ensure that any signal detected is endotoxin-specific. Blood samples were measured for BG, interleukin-6 (IL-6), tumor necrosis factor-alfa (TNF-α) to examine the association between endotoxin signals, BG and inflammation. Results Endotoxin signals were detected in 50% of patients. On repeat measurement with a BG-blocking buffer, all detected endotoxin signals were extinguished. No patient had detectable endotoxemia. Plasma BG levels were significantly elevated in 58% of patients and were higher in those with detectable endotoxin signals using the LAL assay without BG-blocking buffers (78vs.54pg/mL;p<0.001). Endotoxin signal and BG levels did not correlate with levels of TNF-α or IL-6. Conclusion Use of the LAL assay for blood endotoxin detection in dialysis patients has its limitations due to high blood BG. Endotoxemia frequently reported in non-infected hemodialysis patients may be artefactual due to BG interference. PMID:27764208

Kidney cell electrophoresis, continuing task

NASA Technical Reports Server (NTRS)

Todd, P. W.

1985-01-01

Materials and procedures for microgravity electrophoresis of living human embryonic kidney cells were evaluated to provide ground support in the form of analytical cell electrophoresis and flow cytometry. Preflight culture media, electrophoresis buffer, fraction collection media, temperature profiles, and urokinase assay procedures were tested prior to flight. Electrophoretic mobility distributions of aliquots of the cell population to be fractionated in flight were obtained. Cells were prepared in suspension prior to flight in electrophoresis buffer and 10% calf serum. Electrophoretic separation proceeded in electrophoresis buffer without serum in the Continuous Flow Electrophoretic Separator, and fractions were collected into sample bags containing culture medium and concentrated serum. Fractions that yielded enough progeny cells were analyzed for morphology and electrophoretic mobility distributions. It is noted that the lowest mobility fraction studied produced higher mobility progeny while the other fractions produced progeny cells with mobilities related to the fractions from which they were collected.

Low Cost SoC Design of H.264/AVC Decoder for Handheld Video Player

NASA Astrophysics Data System (ADS)

Wisayataksin, Sumek; Li, Dongju; Isshiki, Tsuyoshi; Kunieda, Hiroaki

We propose a low cost and stand-alone platform-based SoC for H.264/AVC decoder, whose target is practical mobile applications such as a handheld video player. Both low cost and stand-alone solutions are particularly emphasized. The SoC, consisting of RISC core and decoder core, has advantages in terms of flexibility, testability and various I/O interfaces. For decoder core design, the proposed H.264/AVC coprocessor in the SoC employs a new block pipelining scheme instead of a conventional macroblock or a hybrid one, which greatly contribute to reducing drastically the size of the core and its pipelining buffer. In addition, the decoder schedule is optimized to block level which is easy to be programmed. Actually, the core size is reduced to 138 KGate with 3.5 kbyte memory. In our practical development, a single external SDRAM is sufficient for both reference frame buffer and display buffer. Various peripheral interfaces such as a compact flash, a digital broadcast receiver and a LCD driver are also provided on a chip.

43 CFR 3931.100 - Boundary pillars and buffer zones.

Code of Federal Regulations, 2013 CFR

2013-10-01

... otherwise specified in writing by the BLM. Boundary and other main pillars may be mined only with the BLM's prior written consent or on the BLM's order. For in-situ operations, a 50-foot buffer zone from the..., mine out and remove all available oil shale in such boundary pillar, both in the lands covered by the...

43 CFR 3931.100 - Boundary pillars and buffer zones.

Code of Federal Regulations, 2012 CFR

2012-10-01

... otherwise specified in writing by the BLM. Boundary and other main pillars may be mined only with the BLM's prior written consent or on the BLM's order. For in-situ operations, a 50-foot buffer zone from the..., mine out and remove all available oil shale in such boundary pillar, both in the lands covered by the...

43 CFR 3931.100 - Boundary pillars and buffer zones.

Code of Federal Regulations, 2014 CFR

2014-10-01

... otherwise specified in writing by the BLM. Boundary and other main pillars may be mined only with the BLM's prior written consent or on the BLM's order. For in-situ operations, a 50-foot buffer zone from the..., mine out and remove all available oil shale in such boundary pillar, both in the lands covered by the...

43 CFR 3931.100 - Boundary pillars and buffer zones.

Code of Federal Regulations, 2011 CFR

2011-10-01

... otherwise specified in writing by the BLM. Boundary and other main pillars may be mined only with the BLM's prior written consent or on the BLM's order. For in-situ operations, a 50-foot buffer zone from the..., mine out and remove all available oil shale in such boundary pillar, both in the lands covered by the...

Universal null DTE (data terminal equipment)

DOEpatents

George, M.; Pierson, L.G.; Wilkins, M.E.

1987-11-09

A communication device in the form of data terminal equipment permits two data communication equipments, each having its own master clock and operating at substantially the same nominal clock rate, to communicate with each other in a multi-segment circuit configuration of a general communication network even when phase or frequency errors exist between the two clocks. Data transmitted between communication equipments of two segments of the communication network is buffered. A variable buffer fill circuit is provided to fill the buffer to a selectable extent prior to initiation of data output clocking. Selection switches are provided to select the degree of buffer preload. A dynamic buffer fill circuit may be incorporated for automatically selecting the buffer fill level as a function of the difference in clock frequencies of the two equipments. Controllable alarm circuitry is provided for selectively generating an underflow or an overflow alarm to one or both of the communicating equipments. 5 figs.

Internode data communications in a parallel computer

DOEpatents

Archer, Charles J.; Blocksome, Michael A.; Miller, Douglas R.; Parker, Jeffrey J.; Ratterman, Joseph D.; Smith, Brian E.

2013-09-03

Internode data communications in a parallel computer that includes compute nodes that each include main memory and a messaging unit, the messaging unit including computer memory and coupling compute nodes for data communications, in which, for each compute node at compute node boot time: a messaging unit allocates, in the messaging unit's computer memory, a predefined number of message buffers, each message buffer associated with a process to be initialized on the compute node; receives, prior to initialization of a particular process on the compute node, a data communications message intended for the particular process; and stores the data communications message in the message buffer associated with the particular process. Upon initialization of the particular process, the process establishes a messaging buffer in main memory of the compute node and copies the data communications message from the message buffer of the messaging unit into the message buffer of main memory.

Internode data communications in a parallel computer

DOEpatents

Archer, Charles J; Blocksome, Michael A; Miller, Douglas R; Parker, Jeffrey J; Ratterman, Joseph D; Smith, Brian E

2014-02-11

Internode data communications in a parallel computer that includes compute nodes that each include main memory and a messaging unit, the messaging unit including computer memory and coupling compute nodes for data communications, in which, for each compute node at compute node boot time: a messaging unit allocates, in the messaging unit's computer memory, a predefined number of message buffers, each message buffer associated with a process to be initialized on the compute node; receives, prior to initialization of a particular process on the compute node, a data communications message intended for the particular process; and stores the data communications message in the message buffer associated with the particular process. Upon initialization of the particular process, the process establishes a messaging buffer in main memory of the compute node and copies the data communications message from the message buffer of the messaging unit into the message buffer of main memory.

Universal null DTE

DOEpatents

George, Michael; Pierson, Lyndon G.; Wilkins, Mark E.

1989-01-01

A communication device in the form of data terminal equipment permits two data communication equipments, each having its own master clock and operating at substantially the same nominal clock rate, to communicate with each other in a multi-segment circuit configuration of a general communication network even when phase or frequency errors exist between the two clocks. Data transmitted between communication equipments of two segments of the communication network is buffered. A variable buffer fill circuit is provided to fill the buffer to a selectable extent prior to initiation of data output clocking. Selection switches are provided to select the degree of buffer preload. A dynamic buffer fill circuit may be incorporated for automatically selecting the buffer fill level as a function of the difference in clock frequencies of the two equipments. Controllable alarm circuitry is provided for selectively generating an underflow or an overflow alarm to one or both of the communicating equipments.

Methyl Bromide Fumigant Management Plan Phase 2 Templates

EPA Pesticide Factsheets

Templates provide a checklist and framework for elements including certified pesticide applicator details, application block, buffer zones, sign posting, tarp plan, soil conditions, air monitoring, and good agricultural practices (GAPs).

High-bandwidth prefetcher for high-bandwidth memory

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

Mehta, Sanyam; Kohn, James Robert; Ernst, Daniel Jonathan

A method for prefetching data into a cache is provided. The method allocates an outstanding request buffer ("ORB"). The method stores in an address field of the ORB an address and a number of blocks. The method issues prefetch requests for a degree number of blocks starting at the address. When a prefetch response is received for all the prefetch requests, the method adjusts the address of the next block to prefetch and adjusts the number of blocks remaining to be retrieved and then issues prefetch requests for a degree number of blocks starting at the adjusted address. The prefetchingmore » pauses when a maximum distance between the reads of the prefetched blocks and the last prefetched block is reached. When a read request for a prefetched block is received, the method resumes prefetching when a resume criterion is satisfied.« less

Chloropicrin Fumigant Management Plan Phase 2 Templates

EPA Pesticide Factsheets

These forms provide a framework for detailing the FMP elements of pesticide products containing the active ingredient chloropicrin, including application block, buffer zones, emergency response plan, tarp plan, soil conditions, and air monitoring.

Intra- and Inter-personal Consequences of Protective Buffering among Cancer Patients and Caregivers

PubMed Central

Langer, Shelby L.; Brown, Jonathon D.; Syrjala, Karen L.

2009-01-01

BACKGROUND Protective buffering refers to hiding cancer-related thoughts and concerns from one’s spouse or partner. This study sought to examine the intra- and inter-personal consequences of protective buffering and motivations for such (desire to shield partner from distress, desire to shield self from distress). METHODS Eighty hematopoietic stem cell transplant patients and their spousal caregivers/ partners completed measures designed to assess protective buffering and relationship satisfaction at two time points: prior to the transplant (T1) and 50 days post-transplant (T2). Overall mental health was also assessed at T2. RESULTS There was moderate agreement between one dyad member’s reported buffering of his/ her partner, and the partner’s perception of the extent to which s/he felt buffered. Caregivers buffered patients more than patients buffered caregivers, especially at T2. The more participants buffered their partners at T2, and the more they felt buffered, the lower their concurrent relationship satisfaction and the poorer their mental health. The latter effect was particularly true for patients who buffered, and patients who felt buffered. With respect to motivations, patients who buffered primarily to protect their partner at T1 reported increases in relationship satisfaction over time, but when they did so at T2, their caregiver reported concurrent decreases in relationship satisfaction. CONCLUSIONS Protective buffering is costly, in that those who buffer and those who feel buffered report adverse psychosocial outcomes. In addition, buffering enacted by patients with an intention to help may prove counterproductive, ultimately hurting the object of such protection. PMID:19731352

Random Walk Graph Laplacian-Based Smoothness Prior for Soft Decoding of JPEG Images.

PubMed

Liu, Xianming; Cheung, Gene; Wu, Xiaolin; Zhao, Debin

2017-02-01

Given the prevalence of joint photographic experts group (JPEG) compressed images, optimizing image reconstruction from the compressed format remains an important problem. Instead of simply reconstructing a pixel block from the centers of indexed discrete cosine transform (DCT) coefficient quantization bins (hard decoding), soft decoding reconstructs a block by selecting appropriate coefficient values within the indexed bins with the help of signal priors. The challenge thus lies in how to define suitable priors and apply them effectively. In this paper, we combine three image priors-Laplacian prior for DCT coefficients, sparsity prior, and graph-signal smoothness prior for image patches-to construct an efficient JPEG soft decoding algorithm. Specifically, we first use the Laplacian prior to compute a minimum mean square error initial solution for each code block. Next, we show that while the sparsity prior can reduce block artifacts, limiting the size of the overcomplete dictionary (to lower computation) would lead to poor recovery of high DCT frequencies. To alleviate this problem, we design a new graph-signal smoothness prior (desired signal has mainly low graph frequencies) based on the left eigenvectors of the random walk graph Laplacian matrix (LERaG). Compared with the previous graph-signal smoothness priors, LERaG has desirable image filtering properties with low computation overhead. We demonstrate how LERaG can facilitate recovery of high DCT frequencies of a piecewise smooth signal via an interpretation of low graph frequency components as relaxed solutions to normalized cut in spectral clustering. Finally, we construct a soft decoding algorithm using the three signal priors with appropriate prior weights. Experimental results show that our proposal outperforms the state-of-the-art soft decoding algorithms in both objective and subjective evaluations noticeably.

Characterization of Micron-Scale Nanotublar Super Dielectric Materials

DTIC Science & Technology

2015-09-01

has been removed). ..................................128  Figure 98.  NTSDM capacitor with Grafoil “ buffer ” and no excess moisture prior to...by arrows) after accumulation of moisture within the capacitor and the appearance of rust on the Grafoil “ buffer ...26]. Nonetheless, the foundational concept of such a device is the storage of charge via an electric field in the space between two conducting

Chloropicrin and 1,3-D Fumigant Management Plan Phase 2 Templates

EPA Pesticide Factsheets

Plans for soil fumigant pesticide products that contain chloropicrin or 1,3-dichloropropene should include application block information, tarp plan, sign posting for treated area and buffer zone, and other requirements.

Metam Sodium and Metam Potassium Fumigant Management Plan Phase 2 Templates

EPA Pesticide Factsheets

These templates provide a framework for structuring and reporting a plan for this type of pesticide product. Required data fields include application block size, buffer zone signage, soil conditions, and tarp plans.

Phase 2 Site-Specific Fumigant Management Plans and Post-Application Summaries

EPA Pesticide Factsheets

New soil fumigant pesticide requirements protect handlers and other workers from exposure risks. FMP elements include application block information, tarp plan, buffer zone and sign posting requirements, air monitoring, and hazard communication.

Paladin® EC (Dimethyl Disulfide, DMDS) Fumigant Safe Handling Guide

EPA Pesticide Factsheets

Certified pesticide applicators are required to provide safety information to handlers working in an application block or buffer zone, including instruction on personal protective equipment, air monitoring, respiratory protection, and exposure mitigation.

Dazomet Fumigant Management Plan Phase 2 Templates

EPA Pesticide Factsheets

These templates provide a framework for reporting application block information, buffer zones, emergency response plan, tarp plan, soil conditions, air monitoring, and more for pesticide products containing the active ingredient dazomet, such as Basamid G.

Reducing interface recombination for Cu(In,Ga)Se{sub 2} by atomic layer deposited buffer layers

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

Hultqvist, Adam; Bent, Stacey F.; Li, Jian V.

2015-07-20

Partial CuInGaSe{sub 2} (CIGS) solar cell stacks with different atomic layer deposited buffer layers and pretreatments were analyzed by photoluminescence (PL) and capacitance voltage (CV) measurements to investigate the buffer layer/CIGS interface. Atomic layer deposited ZnS, ZnO, and SnO{sub x} buffer layers were compared with chemical bath deposited CdS buffer layers. Band bending, charge density, and interface state density were extracted from the CV measurement using an analysis technique new to CIGS. The surface recombination velocity calculated from the density of interface traps for a ZnS/CIGS stack shows a remarkably low value of 810 cm/s, approaching the range of single crystallinemore » II–VI systems. Both the PL spectra and its lifetime depend on the buffer layer; thus, these measurements are not only sensitive to the absorber but also to the absorber/buffer layer system. Pretreatment of the CIGS prior to the buffer layer deposition plays a significant role on the electrical properties for the same buffer layer/CIGS stack, further illuminating the importance of good interface formation. Finally, ZnS is found to be the best performing buffer layer in this study, especially if the CIGS surface is pretreated with potassium cyanide.« less

Reducing interface recombination for Cu(In,Ga)Se 2 by atomic layer deposited buffer layers

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

Hultqvist, Adam; Li, Jian V.; Kuciauskas, Darius

2015-07-20

Partial CuInGaSe2 (CIGS) solar cell stacks with different atomic layer deposited buffer layers and pretreatments were analyzed by photoluminescence (PL) and capacitance voltage (CV) measurements to investigate the buffer layer/CIGS interface. Atomic layer deposited ZnS, ZnO, and SnOx buffer layers were compared with chemical bath deposited CdS buffer layers. Band bending, charge density, and interface state density were extracted from the CV measurement using an analysis technique new to CIGS. The surface recombination velocity calculated from the density of interface traps for a ZnS/CIGS stack shows a remarkably low value of 810 cm/s, approaching the range of single crystalline II-VImore » systems. Both the PL spectra and its lifetime depend on the buffer layer; thus, these measurements are not only sensitive to the absorber but also to the absorber/buffer layer system. Pretreatment of the CIGS prior to the buffer layer deposition plays a significant role on the electrical properties for the same buffer layer/CIGS stack, further illuminating the importance of good interface formation. Finally, ZnS is found to be the best performing buffer layer in this study, especially if the CIGS surface is pretreated with potassium cyanide.« less

Reducing interface recombination for Cu(In,Ga)Se 2 by atomic layer deposited buffer layers

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

Hultqvist, Adam; Li, Jian V.; Kuciauskas, Darius

2015-07-20

Partial CuInGaSe2 (CIGS) solar cell stacks with different atomic layer deposited buffer layers and pretreatments were analyzed by photoluminescence (PL) and capacitance voltage (CV) measurements to investigate the buffer layer/CIGS interface. Atomic layer deposited ZnS, ZnO, and SnOx buffer layers were compared with chemical bath deposited CdS buffer layers. Band bending, charge density, and interface state density were extracted from the CV measurement using an analysis technique new to CIGS. The surface recombination velocity calculated from the density of interface traps for a ZnS/CIGS stack shows a remarkably low value of 810 cm/s, approaching the range of single crystalline II–VImore » systems. Both the PL spectra and its lifetime depend on the buffer layer; thus, these measurements are not only sensitive to the absorber but also to the absorber/buffer layer system. Pretreatment of the CIGS prior to the buffer layer deposition plays a significant role on the electrical properties for the same buffer layer/CIGS stack, further illuminating the importance of good interface formation. Finally, ZnS is found to be the best performing buffer layer in this study, especially if the CIGS surface is pretreated with potassium cyanide.« less

Investigating the Functional Role of Prostate-Specific Membrane Antigen and Its Enzymatic Activity in Prostate Cancer Metastasis

DTIC Science & Technology

2009-11-01

24-well plates and grown for 2-3 days prior to initiating the experiments. Cells were rinsed in Krebs -Ringer buffer, and incubated with mAbs J591...J415, 7E11 at 10µg/ml in Krebs - Ringer buffer at 370C for 30 min. 3H-NAAG were co-incubated along with the respective antibody at 0.8 µci/ml for 60 min...at 370C. Cells were washed in Krebs -Ringer buffer, and lysed in 1N of NaOH. Cell lysates were counted in liquid scintillation counter. PSMA negative

Refining paracervical block techniques for pain control in first trimester surgical abortion: a randomized controlled noninferiority trial.

PubMed

Renner, Regina-Maria; Edelman, Alison B; Nichols, Mark D; Jensen, Jeffrey T; Lim, Jeong Y; Bednarek, Paula H

2016-11-01

Our objective was to evaluate two different aspects of the paracervical block (PCB) technique for first trimester surgical abortion, to compare a 3-min wait prior to cervical dilation to no wait and to compare four-site with two-site injection. We conducted two consecutive randomized, single-blinded noninferiority trials. In the first trial, women <11 weeks gestational age received a 20-mL 1% buffered lidocaine four-site PCB with either a 3-min wait between PCB injection and dilation or no wait. In the second trial, we compared a four-site with a two-site PCB. We evaluated dilation pain [100-mm visual analogue scale (VAS)] as the primary outcome. Secondary outcomes included pain at additional time points, anxiety, satisfaction and adverse events. Both trials fully enrolled (total n=332). Results were inconclusive as to whether no wait was noninferior to waiting 3-min prior to cervical dilation for dilation pain [VAS: 63 mm (SD, 24 mm) vs. 56 mm (SD, 32mm)] and as to whether a two-site PCB was noninferior to a four-site block [VAS: 68 mm (SD, 21 mm) vs. 60 mm (SD, 30 mm)]. Noninferiority analysis was inconclusive because the confidence interval of the mean pain score difference between groups included the predefined inferiority margin of 13-mm pain difference. Superiority analysis showed the four-site PCB to be superior to the two-site PCB. It remained inconclusive whether a 3-min wait time between PCB and cervical dilation provides noninferior pain control for first trimester surgical abortion. However, a four-site PCB appeared to be superior to a two-site PCB. It remained inconclusive whether a 3-min wait time between PCB and cervical dilation or using a two-site instead of a four-site PCB provided noninferior pain control for first trimester surgical abortion. This study did not assess whether the combination of the two separate factors provides additive benefit. Copyright © 2016 Elsevier Inc. All rights reserved.

Safety Information for Fumigant Handlers

EPA Pesticide Factsheets

Available in both English and Spanish, there are two types of information: developed by EPA, and developed by pesticide registrants and approved by EPA. Certified applicators are required to provide this to handlers in application blocks or buffer zones.

Safety Information for Handlers of Pesticide Soil Fumigants

EPA Pesticide Factsheets

Certified applicators are required to provide this training to handlers in an application block or buffer zone. Information must include signs and symptoms of exposure, and where to find the Fumigant Management Plan and Worker Protection Standard.

Experimental Analysis and Computational Modeling of Network States and Drug Responses in the PI3K/Akt/mTOR Network

DTIC Science & Technology

2010-09-01

Fixation was in 2% formaldehyde, followed by permeabilization in 100% methanol at -20 C. Blocking and incubation with primary/secondary antibodies ...was performed in Odyssey blocking buffer (LICOR). Primary antibodies were obtained from Cell Signaling, BD Biosciences, and Santa Cruz...Biotechnology, and Alexa fluor 488-, 555-, or 647-conjugated secondary antibodies were obtained from Invitrogen. Data were collected using an Applied Precision

Correlation between oxalic acid production and tolerance of Tyromyces palustris strain TYP-6137 to N',N-naphthaloylhydroxamine

Treesearch

Rachel A. Arango; Patricia K. Lebow; Frederick III Green

2009-01-01

Eleven strains of T. palustris were evaluated for mass loss and production of phosphate buffer soluble oxalic acid on pine wood blocks treated with 0.5% N’,N-naphthaloylhydroxamine (NHA) in a soil-block test. After 12 weeks higher percentage mass loss was observed in control groups for 10 strains, while TYP-6137 was shown to be tolerant with no difference between the...

Study on the key role of hierarchical microstructure for strength and plasticity in a lath martensitic steel

NASA Astrophysics Data System (ADS)

Yang, Ming; Long, Shao-lei; Liang, Yi-long

2018-03-01

In this paper, the effect of substructure of lath martensite on the mechanical properties was discussed in detail. Results indicated that prior austenite grain, packet and block increase with the increasing of quenching temperature. A good linear relationship exists between the packet, block and prior austenite, which reveal that the size of packet, block depends on prior austenite grain. However, lath is increased with not determined by prior austenite grain. Based on the EBSD analysis, the large ratio of the low angle orientation boundaries determines the better plasticity is obtained in coarse grain. Therefore, the refining of martensite lath or the increase of the low angle orientation plays an important role on improving the plasticity in lath martensite steel.

The Role of Long-Term Tectonic Deformation on the Distribution of Present-Day Seismic Activity in the Caribbean and Central America

NASA Astrophysics Data System (ADS)

Schobelock, J.; Stamps, D. S.; Pagani, M.; Garcia, J.; Styron, R. H.

2017-12-01

The Caribbean and Central America region (CCAR) undergoes the entire spectrum of earthquake types due to its complex tectonic setting comprised of transform zones, young oceanic spreading ridges, and subductions along its eastern and western boundaries. CCAR is, therefore, an ideal setting in which to study the impacts of long-term tectonic deformation on the distribution of present-day seismic activity. In this work, we develop a continuous tectonic strain rate model based on inter-seismic geodetic data and compare it with known active faults and earthquake focal mechanism data. We first create a 0.25o x 0.25o finite element mesh that is comprised of block geometries defined in previously studies. Second, we isolate and remove transient signals from the latest open access community velocity solution from UNAVCO, which includes 339 velocities from COCONet and TLALOCNet GNSS data for the Caribbean and Central America, respectively. In a third step we define zones of deformation and rigidity by creating a buffer around the boundary of each block that varies depending on the size of the block and the expected deformation zone based on locations of GNSS data that are consistent with rigid block motion. We then assign each node within the buffer a 0 for the deforming areas and a plate index outside the buffer for the rigid. Finally, we calculate a tectonic strain rate model for CCAR using the Haines and Holt finite element approach to fit bi-cubic Bessel splines to the the GNSS/GPS data assuming block rotation for zones of rigidity. Our model of the CCAR is consistent with compression along subduction zones, extension across the mid-Pacific Rise, and a combination of compression and extension across the North America - Caribbean plate boundary. The majority of CCAR strain rate magnitudes range from -60 to 60 nanostrains/yr. Modeling results are then used to calculate expected faulting behaviors that we compare with mapped geologic faults and seismic activity.

Amphiphilic Polysaccharide Block Copolymers for pH-Responsive Micellar Nanoparticles.

PubMed

Breitenbach, Benjamin B; Schmid, Ira; Wich, Peter R

2017-09-11

A full polysaccharide amphiphilic block copolymer was prepared from end group-functionalized dextrans using copper-mediated azide-alkyne click chemistry. Sufficient modification of the reducing end in both blocks was achieved by microwave-enhanced reductive amination in a borate-buffer/methanol solvent system. The combination of a hydrophilic dextran block with a hydrophobic acetalated dextran block results in an amphiphilic structure that turns water-soluble upon acid treatment. The material has a low critical micelle concentration and self-assembles in water to spherical micellar nanoparticles. The formed nanoparticles have a narrow size distribution below 70 nm in diameter and disassemble in slightly acidic conditions. The amphiphilic polysaccharide system shows low toxicity and can stabilize the hydrophobic model drug curcumin in aqueous solutions over extended time periods.

Polymeric micellar pH-sensitive drug delivery system for doxorubicin.

PubMed

Hrubý, Martin; Konák, Cestmír; Ulbrich, Karel

2005-03-02

A novel polymeric micellar pH-sensitive system for delivery of doxorubicin (DOX) is described. Polymeric micelles were prepared by self-assembly of amphiphilic diblock copolymers in aqueous solutions. The copolymers consist of a biocompatible hydrophilic poly(ethylene oxide) (PEO) block and a hydrophobic block containing covalently bound anthracycline antibiotic DOX. The starting block copolymers poly(ethylene oxide)-block-poly(allyl glycidyl ether) (PEO-PAGE) with a very narrow molecular weight distribution (Mw/Mn ca. 1.05) were prepared by anionic ring opening polymerization using sodium salt of poly(ethylene oxide) monomethyl ether as macroinitiator and allyl glycidyl ether as functional monomer. The copolymers were covalently modified via reactive double bonds by the addition of methyl sulfanylacetate. The resulting ester subsequently reacted with hydrazine hydrate yielding polymer hydrazide. The hydrazide was coupled with DOX yielding pH-sensitive hydrazone bonds between the drug and carrier. The resulting conjugate containing ca. 3 wt.% DOX forms micelles with Rh(a)=104 nm in phosphate-buffered saline. After incubation in buffers at 37 degrees C DOX was released faster at pH 5.0 (close to pH in endosomes; 43% DOX released within 24 h) than at pH 7.4 (pH of blood plasma; 16% DOX released within 24 h). Cleavage of hydrazone bonds between DOX and carrier continues even after plateau in the DOX release from micelles incubated in aqueous solutions is reached.

Block-based scalable wavelet image codec

NASA Astrophysics Data System (ADS)

Bao, Yiliang; Kuo, C.-C. Jay

1999-10-01

This paper presents a high performance block-based wavelet image coder which is designed to be of very low implementational complexity yet with rich features. In this image coder, the Dual-Sliding Wavelet Transform (DSWT) is first applied to image data to generate wavelet coefficients in fixed-size blocks. Here, a block only consists of wavelet coefficients from a single subband. The coefficient blocks are directly coded with the Low Complexity Binary Description (LCBiD) coefficient coding algorithm. Each block is encoded using binary context-based bitplane coding. No parent-child correlation is exploited in the coding process. There is also no intermediate buffering needed in between DSWT and LCBiD. The compressed bit stream generated by the proposed coder is both SNR and resolution scalable, as well as highly resilient to transmission errors. Both DSWT and LCBiD process the data in blocks whose size is independent of the size of the original image. This gives more flexibility in the implementation. The codec has a very good coding performance even the block size is (16,16).

Fast and Non-Toxic In Situ Hybridization without Blocking of Repetitive Sequences

PubMed Central

Matthiesen, Steen H.; Hansen, Charles M.

2012-01-01

Formamide is the preferred solvent to lower the melting point and annealing temperature of nucleic acid strands in in situ hybridization (ISH). A key benefit of formamide is better preservation of morphology due to a lower incubation temperature. However, in fluorescence in situ hybridization (FISH), against unique DNA targets in tissue sections, an overnight hybridization is required to obtain sufficient signal intensity. Here, we identified alternative solvents and developed a new hybridization buffer that reduces the required hybridization time to one hour (IQFISH method). Remarkably, denaturation and blocking against repetitive DNA sequences to prevent non-specific binding is not required. Furthermore, the new hybridization buffer is less hazardous than formamide containing buffers. The results demonstrate a significant increased hybridization rate at a lowered denaturation and hybridization temperature for both DNA and PNA (peptide nucleic acid) probes. We anticipate that these formamide substituting solvents will become the foundation for changes in the understanding and performance of denaturation and hybridization of nucleic acids. For example, the process time for tissue-based ISH for gene aberration tests in cancer diagnostics can be reduced from days to a few hours. Furthermore, the understanding of the interactions and duplex formation of nucleic acid strands may benefit from the properties of these solvents. PMID:22911704

Loss of glycogen during preconditioning is not a prerequisite for protection of the rabbit heart.

PubMed

Weinbrenner, C; Wang, P; Downey, J M

1996-01-01

Depletion of glycogen has been proposed as the mechanism of protection from ischemic preconditioning. The hypothesis was tested by seeing whether pharmacological manipulation of preconditioning causes parallel changes in cardiac glycogen content. Five groups of isolated rabbit hearts were studied. Group 1 experienced 30 min of ischemia only. Group 2 (PC) was preconditioned with 5 min of global ischemia followed by 10 min of reperfusion. Group 3 was preconditioned with 5 min exposure to 400 nM bradykinin followed by a 10 min washout period. Group 4 experienced exposure to 10 microM adenosine followed by a 10 min washout period, and the fifth group was also preconditioned with 5 min ischemia and 10 min reperfusion but 100 microM 8-(p-sulfophenyl)theophylline (SPT), which blocks adenosine receptors, was included in the buffer to block preconditioning's protection. Transmural biopsies were taken before treatment, just prior to the 30 min period of global ischemia, and after 30 min of global ischemia. Glycogen in the samples was digested with amyloglucosidase and the resulting glucose was assayed. Baseline glycogen averaged 17.3 +/- 0.6 mumol glucose/g wet weight. After preconditioning glycogen decreased to 13.3 +/- 1.3 mumol glucose/g wet weight (p < 0.005 vs. baseline). Glycogen was similarly depleted after pharmacological preconditioning with adenosine (14.0 +/- 1.0 mumol glucose/g wet weight, p < 0.05 vs. baseline) suggesting a correlation. However, when preconditioning was performed in the presence of SPT, which blocks protection, glycogen was also depleted by the same amount (13.3 +/- 0.7 mumol glucose/g wet weight, p = ns vs. PC). Bradykinin, which also mimics preconditioning, caused no depletion of glycogen (16.3 +/- 0.8 mumol glucose/g wet weight, p = ns vs. baseline). Because preconditioning with bradykinin did not deplete glycogen and because glycogen continued to be low when protection from preconditioning was blocked with SPT, we conclude that loss of glycogen per se does not cause the protection of preconditioning.

Gibraltar v 1.0

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

CURRY, MATTHEW LEON; WARD, H. LEE; & SKJELLUM, ANTHONY

Gibraltar is a library and associated test suite which performs Reed-Solomon coding and decoding of data buffers using graphics processing units which support NVIDIA's CUDA technology. This library is used to generate redundant data allowing for recovery of lost information. For example, a user can generate m new blocks of data from n original blocks, distributing those pieces over n+m devices. If any m devices fail, the contents of those devices can be recovered from the contents of the other n devices, even if some of the original blocks are lost. This is a generalized description of RAID, a techniquemore » for increasing data storage speed and size.« less

A simulation for gravity fine structure recovery from low-low GRAVSAT SST data

NASA Technical Reports Server (NTRS)

Estes, R. H.; Lancaster, E. R.

1976-01-01

Covariance error analysis techniques were applied to investigate estimation strategies for the low-low SST mission for accurate local recovery of gravitational fine structure, considering the aliasing effects of unsolved for parameters. A 5 degree by 5 degree surface density block representation of the high order geopotential was utilized with the drag-free low-low GRAVSAT configuration in a circular polar orbit at 250 km altitude. Recovery of local sets of density blocks from long data arcs was found not to be feasible due to strong aliasing effects. The error analysis for the recovery of local sets of density blocks using independent short data arcs demonstrated that the estimation strategy of simultaneously estimating a local set of blocks covered by data and two "buffer layers" of blocks not covered by data greatly reduced aliasing errors.

'Trophic whales' as biotic buffers: weak interactions stabilize ecosystems against nutrient enrichment.

PubMed

Schwarzmüller, Florian; Eisenhauer, Nico; Brose, Ulrich

2015-05-01

Human activities may compromise biodiversity if external stressors such as nutrient enrichment endanger overall network stability by inducing unstable dynamics. However, some ecosystems maintain relatively high diversity levels despite experiencing continuing disturbances. This indicates that some intrinsic properties prevent unstable dynamics and resulting extinctions. Identifying these 'ecosystem buffers' is crucial for our understanding of the stability of ecosystems and an important tool for environmental and conservation biologists. In this vein, weak interactions have been suggested as stabilizing elements of complex systems, but their relevance has rarely been tested experimentally. Here, using network and allometric theory, we present a novel concept for a priori identification of species that buffer against externally induced instability of increased population oscillations via weak interactions. We tested our model in a microcosm experiment using a soil food-web motif. Our results show that large-bodied species feeding at the food web's base, so called 'trophic whales', can buffer ecosystems against unstable dynamics induced by nutrient enrichment. Similar to the functionality of chemical or mechanical buffers, they serve as 'biotic buffers' that take up stressor effects and thus protect fragile systems from instability. We discuss trophic whales as common functional building blocks across ecosystems. Considering increasing stressor effects under anthropogenic global change, conservation of these network-intrinsic biotic buffers may help maintain the stability and diversity of natural ecosystems. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

Polymeric microcapsules assembled from a cationic/zwitterionic pair of responsive block copolymer micelles.

PubMed

Addison, Timothy; Cayre, Olivier J; Biggs, Simon; Armes, Steven P; York, David

2010-05-04

Using a layer-by-layer (LbL) approach, this work presents the preparation of hollow microcapsules with a membrane constructed entirely from a cationic/zwitterionic pair of pH-responsive block copolymer micelles. Our previous work with such systems highlighted that, in order to retain the responsive nature of the individual micelles contained within the multilayer membranes, it is important to optimize the conditions required for the selective dissolution of the sacrificial particulate templates. Consequently, here, calcium carbonate particles have been employed as colloidal templates as they can be easily dissolved in aqueous environments with the addition of chelating agents such as ethylenediaminetetraacetic acid (EDTA). Furthermore, the dissolution can be carried out in solutions buffered to a desirable pH so not to adversely affect the pH sensitive micelles forming the capsule membranes. First, we have deposited alternating layers of anionic poly[2-(dimethylamino)ethyl methacrylate-block-poly(2-(diethylamino)ethyl methacrylate)] (PDMA-PDEA) and cationic poly(2-(diethylamino)ethyl)methacrylate-block-poly(methacrylic acid) (PDEA-PMAA) copolymer micelles onto calcium carbonate colloidal templates. After deposition of five micelle bilayers, addition of dilute EDTA solution resulted in dissolution of the calcium carbonate and formation of hollow polymer capsules. The capsules were imaged using atomic force microscopy (AFM) and scanning electron microscopy (SEM), which shows that the micelle/micelle membrane is sufficiently robust to withstand dissolution of the supporting template. Quartz crystal microbalance studies were conducted and provide good evidence that the micelle multilayer structure is retained after EDTA treatment. In addition, a hydrophobic dye was incorporated into the micelle cores prior to adsorption. After dissolution of the particle template, the resulting hollow capsules retained a high concentration of dye, suggesting that the core/shell structure of the micelles remains intact. Finally, thermogravimetric analysis (TGA) of dried capsules confirmed complete removal of the sacrificial inorganic template. As far as we are aware, this is the first demonstration of LbL assembled capsules composed entirely from responsive block copolymer micelles. The results presented here when combined with our previous findings demonstrate that such systems have potential application in the encapsulation and triggered release of actives.

Strengthening and toughening mechanisms in low-c microalloyed martensitic steel as influenced by austenite conditioning

NASA Astrophysics Data System (ADS)

Kennett, Shane C.

Three low-carbon ASTM A514 microalloyed steels were used to assess the effects of austenite conditioning on the microstructure and mechanical properties of martensite. A range of prior austenite grain sizes with and without thermomechanical processing were produced in a Gleeble RTM 3500 and direct-quenched. Samples in the as-quenched, low temperature tempered, and high temperature tempered conditions were studied. The microstructure was characterized with scanning electron microscopy, electron backscattered diffraction, transmission electron microscopy, and x-ray diffraction. The uniaxial tensile properties and Charpy V-notch properties were measured and compared with the microstructural features (prior austenite grain size, packet size, block size, lath boundaries, and dislocation density). For the equiaxed prior austenite grain conditions, prior austenite grain size refinement decreases the packet size, decreases the block size, and increases the dislocation density of as-quenched martensite. However, after high temperature tempering the dislocation density decreases with prior austenite grain size refinement. Thermomechanical processing increases the low angle substructure, increases the dislocation density, and decreases the block size of as-quenched martensite. The dislocation density increase and block size refinement is sensitive to the austenite grain size before ausforming. The larger prior austenite grain size conditions have a larger increase in dislocation density, but the small prior austenite grain size conditions have the largest refinement in block size. Additionally, for the large prior austenite grain size conditions, the packet size increases with thermomechanical processing. The strength of martensite is often related to an effective grain size or carbon concentration. For the current work, it was concluded that the strength of martensite is primarily controlled by the dislocation density and dislocation substructure; which is related to a grain size and carbon concentration. In the microyielding regime, the strength and work hardening is related to the motion of unpinned dislocation segments. However, with tensile strain, a dislocation cell structure is developed and the flow strength (greater than 1% offset) is controlled by the dislocation density following a Taylor hardening model, thereby ruling out any grain size effects on the flow strength. Additionally, it is proposed that lath boundaries contribute to strength. It is shown that the strength differences associated with thermomechanically processed steels can be fully accounted for by dislocation density differences and the effect of lath boundaries. The low temperature ductile to brittle transition of martensite is controlled by the martensite block size, packet size, and prior austenite grain size. However, the effect of block size is likely small in comparison. The ductile to brittle transition temperature is best correlated to the inverse square root of the martensite packet size because large crack deflections are typical at packet boundaries.

A 128K-bit CCD buffer memory system

NASA Technical Reports Server (NTRS)

Siemens, K. H.; Wallace, R. W.; Robinson, C. R.

1976-01-01

A prototype system was implemented to demonstrate that CCD's can be applied advantageously to the problem of low power digital storage and particularly to the problem of interfacing widely varying data rates. 8K-bit CCD shift register memories were used to construct a feasibility model 128K-bit buffer memory system. Peak power dissipation during a data transfer is less than 7 W., while idle power is approximately 5.4 W. The system features automatic data input synchronization with the recirculating CCD memory block start address. Descriptions are provided of both the buffer memory system and a custom tester that was used to exercise the memory. The testing procedures and testing results are discussed. Suggestions are provided for further development with regards to the utilization of advanced versions of CCD memory devices to both simplified and expanded memory system applications.

Continuous processing of recombinant proteins: Integration of inclusion body solubilization and refolding using simulated moving bed size exclusion chromatography with buffer recycling.

PubMed

Wellhoefer, Martin; Sprinzl, Wolfgang; Hahn, Rainer; Jungbauer, Alois

2013-12-06

An integrated process which combines continuous inclusion body dissolution with NaOH and continuous matrix-assisted refolding based on closed-loop simulated moving bed size exclusion chromatography was designed and experimentally evaluated at laboratory scale. Inclusion bodies from N(pro) fusion pep6His and N(pro) fusion MCP1 from high cell density fermentation were continuously dissolved with NaOH, filtered and mixed with concentrated refolding buffer prior to refolding by size exclusion chromatography (SEC). This process enabled an isocratic operation of the simulated moving bed (SMB) system with a closed-loop set-up with refolding buffer as the desorbent buffer and buffer recycling by concentrating the raffinate using tangential flow filtration. With this continuous refolding process, we increased the refolding and cleavage yield of both model proteins by 10% compared to batch dilution refolding. Furthermore, more than 99% of the refolding buffer of the raffinate could be recycled which reduced the buffer consumption significantly. Based on the actual refolding data, we compared throughput, productivity, and buffer consumption between two batch dilution refolding processes - one using urea for IB dissolution, the other one using NaOH for IB dissolution - and our continuous refolding process. The higher complexity of the continuous refolding process was rewarded with higher throughput and productivity as well as significantly lower buffer consumption compared to the batch dilution refolding processes. Copyright © 2013 Elsevier B.V. All rights reserved.

On optimizing the blocking step of indirect enzyme-linked immunosorbent assay for Epstein-Barr virus serology.

PubMed

Lim, Chun Shen; Krishnan, Gopala; Sam, Choon Kook; Ng, Ching Ching

2013-01-16

Because blocking agent occupies most binding surface of a solid phase, its ability to prevent nonspecific binding determines the signal-to-noise ratio (SNR) and reliability of an enzyme-linked immunosorbent assay (ELISA). We demonstrate a stepwise approach to seek a compatible blocking buffer for indirect ELISA, via a case-control study (n=176) of Epstein-Barr virus (EBV)-associated nasopharyngeal carcinoma (NPC). Regardless of case-control status, we found that synthetic polymer blocking agents, mainly Ficoll and poly(vinyl alcohol) (PVA) were able to provide homogeneous backgrounds among samples, as opposed to commonly used blocking agents, notably nonfat dry milk (NFDM). The SNRs for NPC samples that correspond to blocking using PVA were approximately 3-fold, on average, higher than those blocking using NFDM. Both intra- and inter-assay precisions of PVA-based assays were <14%. A blocking agent of choice should have tolerable sample backgrounds from both cases and controls to ensure the reliability of an immunoassay. Copyright © 2012 Elsevier B.V. All rights reserved.

AlGaN/GaN High Electron Mobility Transistor Grown and Fabricated on ZrTi Metallic Alloy Buffer Layers

DOE PAGES

Ren, Fan; Pearton, Stephen J.; Ahn, Shihyun; ...

2017-09-26

AlGaN/GaN high electron mobility transistors (HEMTs) were demonstrated for structures grown on ZrTi metallic alloy buffer layers, which provided lattice matching of the in-plane lattice parameter (“a-parameter”) to hexagonal GaN. The quality of the GaN buffer layer and HEMT structure were confirmed with X-ray 2θ and rocking scans as well as cross-section transmission electron microscopy (TEM) images. The X-ray 2θ scans showed full widths at half maximum (FWHM) of 0.06°, 0.05° and 0.08° for ZrTi alloy, GaN buffer layer, and the entire HEMT structure, respectively. TEM of the lower section of the HEMT structure containing the GaN buffer layer andmore » the AlN/ZrTi/AlN stack on the Si substrate showed that it was important to grow AlN on the top of ZrTi prior to growing the GaN buffer layer. Finally, the estimated threading dislocation (TD) density in the GaN channel layer of the HEMT structure was in the 10 8 cm -2 range.« less

Fatigue of graphite/epoxy buffer strip panels with center cracks

NASA Technical Reports Server (NTRS)

Bigelow, C. A.

1985-01-01

The effects of fatigue loading on the behavior of graphite/epoxy panels with either S-Glass or Kevlar-49 buffer strips is studied. Buffer strip panels are fatigued and tested in tension to measure their residual strength with crack-like damage. Panels are made with 45/0/-45/90 sub 2s layup with either S-Glass or Kevlar-49 buffer strip material. The buffer strips are parallel to the loading direction and made by replacing narrow strips of the 0-degree graphite plies with strips of either 0-degree S-Glass/epoxy or Kevlar-49/epoxy on a one-for-one basis. The panels are subjected to a fatigue loading spectrum MINITWIST, the shortened version of the standardized load program for the wing lower surface of a transport aircraft. Two levels of maximum strain are used in the spectrum with three durations of the fatigue spectrum. One group of panels is preloaded prior to the application of the fatigue cycling. The preload consists of statistically loading the spectrum in tension until the crack-tip damage zone reaches the ajacent buffer strips. After fatigue loading, all specimens are statistically loaded in tension to failure to determine their residual strengths.

Conservation Beyond Park Boundaries: The Impact of Buffer Zones on Deforestation and Mining Concessions in the Peruvian Amazon.

PubMed

Weisse, Mikaela J; Naughton-Treves, Lisa C

2016-08-01

Many researchers have tested whether protected areas save tropical forest, but generally focus on parks and reserves, management units that have internationally recognized standing and clear objectives. Buffer zones have received considerably less attention because of their ambiguous rules and often informal status. Although buffer zones are frequently dismissed as ineffective, they warrant attention given the need for landscape-level approaches to conservation and their prevalence around the world-in Peru, buffer zones cover >10 % of the country. This study examines the effectiveness of buffer zones in the Peruvian Amazon to (a) prevent deforestation and (b) limit the extent of mining concessions. We employ covariate matching to determine the impact of 13 buffer zones on deforestation and mining concessions from 2007 to 2012. Despite variation between sites, these 13 buffer zones have prevented ~320 km(2) of forest loss within their borders during the study period and ~1739 km(2) of mining concessions, an outcome associated with the special approval process for granting formal concessions in these areas. However, a closer look at the buffer zone around the Tambopata National Reserve reveals the difficulties of controlling illegal and informal activities. According to interviews with NGO employees, government officials, and community leaders, enforcement of conservation is limited by uncertain institutional responsibilities, inadequate budgets, and corruption, although formal and community-based efforts to block illicit mining are on the rise. Landscape-level conservation not only requires clear legal protocol for addressing large-scale, formal extractive activities, but there must also be strategies and coordination to combat illegal activities.

Conservation Beyond Park Boundaries: The Impact of Buffer Zones on Deforestation and Mining Concessions in the Peruvian Amazon

NASA Astrophysics Data System (ADS)

Weisse, Mikaela J.; Naughton-Treves, Lisa C.

2016-08-01

Many researchers have tested whether protected areas save tropical forest, but generally focus on parks and reserves, management units that have internationally recognized standing and clear objectives. Buffer zones have received considerably less attention because of their ambiguous rules and often informal status. Although buffer zones are frequently dismissed as ineffective, they warrant attention given the need for landscape-level approaches to conservation and their prevalence around the world—in Peru, buffer zones cover >10 % of the country. This study examines the effectiveness of buffer zones in the Peruvian Amazon to (a) prevent deforestation and (b) limit the extent of mining concessions. We employ covariate matching to determine the impact of 13 buffer zones on deforestation and mining concessions from 2007 to 2012. Despite variation between sites, these 13 buffer zones have prevented ~320 km2 of forest loss within their borders during the study period and ~1739 km2 of mining concessions, an outcome associated with the special approval process for granting formal concessions in these areas. However, a closer look at the buffer zone around the Tambopata National Reserve reveals the difficulties of controlling illegal and informal activities. According to interviews with NGO employees, government officials, and community leaders, enforcement of conservation is limited by uncertain institutional responsibilities, inadequate budgets, and corruption, although formal and community-based efforts to block illicit mining are on the rise. Landscape-level conservation not only requires clear legal protocol for addressing large-scale, formal extractive activities, but there must also be strategies and coordination to combat illegal activities.

Mean-velocity profile of smooth channel flow explained by a cospectral budget model with wall-blockage

DOE PAGES

McColl, Kaighin A.; Katul, Gabriel G.; Gentine, Pierre; ...

2016-03-16

A series of recent studies has shown that a model of the turbulent vertical velocity variance spectrum (F vv) combined with a simplified cospectral budget can reproduce many macroscopic flow properties of turbulent wall-bounded flows, including various features of the mean-velocity profile (MVP), i.e., the "law of the wall". While the approach reasonably models the MVP's logarithmic layer, the buffer layer displays insufficient curvature compared to measurements. The assumptions are re-examined here using a direct numerical simulation (DNS) dataset at moderate Reynolds number that includes all the requisite spectral and co-spectral information. Starting with several hypotheses for the cause ofmore » the "missing" curvature in the buffer layer, it is shown that the curvature deficit is mainly due to mismatches between (i) the modelled and DNS-observed pressure-strain terms in the cospectral budget and (ii) the DNS-observed F vv and the idealized form used in previous models. By replacing the current parameterization for the pressure-strain term with an expansive version that directly accounts for wall-blocking effects, the modelled and DNS reported pressure-strain profiles match each other in the buffer and logarithmic layers. Forcing the new model with DNS-reported F vv rather than the idealized form previously used reproduces the missing buffer layer curvature to high fidelity thereby confirming the "spectral link" between F vv and the MVP across the full profile. A broad implication of this work is that much of the macroscopic properties of the flow (such as the MVP) may be derived from the energy distribution in turbulent eddies (i.e., F vv) representing the microstate of the flow, provided the link between them accounts for wall-blocking.« less

Control of metamorphic buffer structure and device performance of In(x)Ga(1-x)As epitaxial layers fabricated by metal organic chemical vapor deposition.

PubMed

Nguyen, H Q; Yu, H W; Luc, Q H; Tang, Y Z; Phan, V T H; Hsu, C H; Chang, E Y; Tseng, Y C

2014-12-05

Using a step-graded (SG) buffer structure via metal-organic chemical vapor deposition, we demonstrate a high suitability of In0.5Ga0.5As epitaxial layers on a GaAs substrate for electronic device application. Taking advantage of the technique's precise control, we were able to increase the number of SG layers to achieve a fairly low dislocation density (∼10(6) cm(-2)), while keeping each individual SG layer slightly exceeding the critical thickness (∼80 nm) for strain relaxation. This met the demanded but contradictory requirements, and even offered excellent scalability by lowering the whole buffer structure down to 2.3 μm. This scalability overwhelmingly excels the forefront studies. The effects of the SG misfit strain on the crystal quality and surface morphology of In0.5Ga0.5As epitaxial layers were carefully investigated, and were correlated to threading dislocation (TD) blocking mechanisms. From microstructural analyses, TDs can be blocked effectively through self-annihilation reactions, or hindered randomly by misfit dislocation mechanisms. Growth conditions for avoiding phase separation were also explored and identified. The buffer-improved, high-quality In0.5Ga0.5As epitaxial layers enabled a high-performance, metal-oxide-semiconductor capacitor on a GaAs substrate. The devices displayed remarkable capacitance-voltage responses with small frequency dispersion. A promising interface trap density of 3 × 10(12) eV(-1) cm(-2) in a conductance test was also obtained. These electrical performances are competitive to those using lattice-coherent but pricey InGaAs/InP systems.

Calibration and validation of rockfall models

NASA Astrophysics Data System (ADS)

Frattini, Paolo; Valagussa, Andrea; Zenoni, Stefania; Crosta, Giovanni B.

2013-04-01

Calibrating and validating landslide models is extremely difficult due to the particular characteristic of landslides: limited recurrence in time, relatively low frequency of the events, short durability of post-event traces, poor availability of continuous monitoring data, especially for small landslide and rockfalls. For this reason, most of the rockfall models presented in literature completely lack calibration and validation of the results. In this contribution, we explore different strategies for rockfall model calibration and validation starting from both an historical event and a full-scale field test. The event occurred in 2012 in Courmayeur (Western Alps, Italy), and caused serious damages to quarrying facilities. This event has been studied soon after the occurrence through a field campaign aimed at mapping the blocks arrested along the slope, the shape and location of the detachment area, and the traces of scars associated to impacts of blocks on the slope. The full-scale field test was performed by Geovert Ltd in the Christchurch area (New Zealand) after the 2011 earthquake. During the test, a number of large blocks have been mobilized from the upper part of the slope and filmed with high velocity cameras from different viewpoints. The movies of each released block were analysed to identify the block shape, the propagation path, the location of impacts, the height of the trajectory and the velocity of the block along the path. Both calibration and validation of rockfall models should be based on the optimization of the agreement between the actual trajectories or location of arrested blocks and the simulated ones. A measure that describe this agreement is therefore needed. For calibration purpose, this measure should simple enough to allow trial and error repetitions of the model for parameter optimization. In this contribution we explore different calibration/validation measures: (1) the percentage of simulated blocks arresting within a buffer of the actual blocks, (2) the percentage of trajectories passing through the buffer of the actual rockfall path, (3) the mean distance between the location of arrest of each simulated blocks and the location of the nearest actual blocks; (4) the mean distance between the location of detachment of each simulated block and the location of detachment of the actual block located closer to the arrest position. By applying the four measures to the case studies, we observed that all measures are able to represent the model performance for validation purposes. However, the third measure is more simple and reliable than the others, and seems to be optimal for model calibration, especially when using a parameter estimation and optimization modelling software for automated calibration.

The effect of respiration buffer composition on mitochondrial metabolism and function.

PubMed

Wollenman, Lucas C; Vander Ploeg, Matthew R; Miller, Mackinzie L; Zhang, Yizhu; Bazil, Jason N

2017-01-01

Functional studies on isolated mitochondria critically rely on the right choice of respiration buffer. Differences in buffer composition can lead to dramatically different respiration rates leading to difficulties in comparing prior studies. The ideal buffer facilities high ADP-stimulated respiratory rates and minimizes substrate transport effects so that the ability to distinguish between various treatments and conditions is maximal. In this study, we analyzed a variety of respiration buffers and substrate combinations to determine the optimal conditions to support mitochondrial function through ADP-stimulated respiration and uncoupled respiration using FCCP. The buffers consisted of a standard KCl based buffer (B1) and three modified buffers with chloride replaced by the K-lactobionate, sucrose, and the antioxidant taurine (B2) or K-gluconate (B3). The fourth buffer (B4) was identical to B2 except that K-lactobionate was replaced with K-gluconate. The substrate combinations consisted of metabolites that utilize different pathways of mitochondrial metabolism. To test mitochondrial function, we used isolated cardiac guinea pig mitochondria and measured oxygen consumption for three respiratory states using an Oroboros Oxygraph-2k. These states were the leak state (energized mitochondria in the absence of adenylates), ADP-stimulated state (energized mitochondria in the presence of saturating ADP concentrations), and uncoupled state (energized mitochondria in the presence of FCCP). On average across all substrate combinations, buffers B2, B3, and B4 had an increase of 16%, 26%, and 35% for the leak state, ADP-simulated state, and uncoupled state, respectively, relative to rates using B1. The common feature distinguishing these buffers from B1 is the notable lack of high chloride concentrations. Based on the respiratory rate metrics obtained with the substrate combinations, we conclude that the adenine nucleotide translocase, the dicarboxylate carrier, and the alpha-ketoglutarate exchanger are partially inhibited by chloride. Therefore, when the goal is to maximize ADP-stimulated respiration, buffers containing K-lactobionate or K-gluconate are superior choices compared to the standard KCl-based buffers.

The effect of respiration buffer composition on mitochondrial metabolism and function

PubMed Central

Wollenman, Lucas C.; Vander Ploeg, Matthew R.; Miller, Mackinzie L.; Zhang, Yizhu

2017-01-01

Functional studies on isolated mitochondria critically rely on the right choice of respiration buffer. Differences in buffer composition can lead to dramatically different respiration rates leading to difficulties in comparing prior studies. The ideal buffer facilities high ADP-stimulated respiratory rates and minimizes substrate transport effects so that the ability to distinguish between various treatments and conditions is maximal. In this study, we analyzed a variety of respiration buffers and substrate combinations to determine the optimal conditions to support mitochondrial function through ADP-stimulated respiration and uncoupled respiration using FCCP. The buffers consisted of a standard KCl based buffer (B1) and three modified buffers with chloride replaced by the K-lactobionate, sucrose, and the antioxidant taurine (B2) or K-gluconate (B3). The fourth buffer (B4) was identical to B2 except that K-lactobionate was replaced with K-gluconate. The substrate combinations consisted of metabolites that utilize different pathways of mitochondrial metabolism. To test mitochondrial function, we used isolated cardiac guinea pig mitochondria and measured oxygen consumption for three respiratory states using an Oroboros Oxygraph-2k. These states were the leak state (energized mitochondria in the absence of adenylates), ADP-stimulated state (energized mitochondria in the presence of saturating ADP concentrations), and uncoupled state (energized mitochondria in the presence of FCCP). On average across all substrate combinations, buffers B2, B3, and B4 had an increase of 16%, 26%, and 35% for the leak state, ADP-simulated state, and uncoupled state, respectively, relative to rates using B1. The common feature distinguishing these buffers from B1 is the notable lack of high chloride concentrations. Based on the respiratory rate metrics obtained with the substrate combinations, we conclude that the adenine nucleotide translocase, the dicarboxylate carrier, and the alpha-ketoglutarate exchanger are partially inhibited by chloride. Therefore, when the goal is to maximize ADP-stimulated respiration, buffers containing K-lactobionate or K-gluconate are superior choices compared to the standard KCl-based buffers. PMID:29091971

Designing a VMEbus FDDI adapter card

NASA Astrophysics Data System (ADS)

Venkataraman, Raman

1992-03-01

This paper presents a system architecture for a VMEbus FDDI adapter card containing a node core, FDDI block, frame buffer memory and system interface unit. Most of the functions of the PHY and MAC layers of FDDI are implemented with National's FDDI chip set and the SMT implementation is simplified with a low cost microcontroller. The factors that influence the system bus bandwidth utilization and FDDI bandwidth utilization are the data path and frame buffer memory architecture. The VRAM based frame buffer memory has two sections - - LLC frame memory and SMT frame memory. Each section with an independent serial access memory (SAM) port provides an independent access after the initial data transfer cycle on the main port and hence, the throughput is maximized on each port of the memory. The SAM port simplifies the system bus master DMA design and the VMEbus interface can be designed with low-cost off-the-shelf interface chips.

Radiation heat transfer calculations for the uranium fuel-containment region of the nuclear light bulb engine.

NASA Technical Reports Server (NTRS)

Rodgers, R. J.; Latham, T. S.; Krascella, N. L.

1971-01-01

Calculation results are reviewed of the radiant heat transfer characteristics in the fuel and buffer gas regions of a nuclear light bulb engine based on the transfer of energy by thermal radiation from gaseous uranium fuel in a neon vortex, through an internally cooled transparent wall, to seeded hydrogen propellant. The results indicate that the fraction of UV energy incident on the transparent walls increases with increasing power level. For the reference engine power level of 4600 megw, it is necessary to employ space radiators to reject the UV radiated energy absorbed by the transparent walls. This UV energy can be blocked by employing nitric oxide and oxygen seed gases in the fuel and buffer gas regions. However, this results in increased UV absorption in the buffer gas which also requires space radiators to reject the heat load.

Formation of cage-like particles by poly(amino acid)-based block copolymers in aqueous solution.

PubMed Central

Cudd, A; Bhogal, M; O'Mullane, J; Goddard, P

1991-01-01

When dissolved in N,N-dimethylformamide and then dialyzed against phosphate-buffered saline, A-B-A block copolymers composed of poly [N5-(2-hydroxyethyl)-L-glutamine]-block-poly(gamma-benzyl-L-glutamate)- block-poly [N5-(2-hydroxyethyl)-L-glutamine] form particles. The particles are cage-like structures with average diameters of 300 nm (average polydispersity, 0.3-0.5). They are stable in aqueous solution at 4 degrees C for up to 3 weeks, at which time flocculation becomes apparent. Negative staining and freeze-fracture electron microscopy suggest that cage-like particles are formed by selective association of segregated micelle populations. A model of particle formation is presented in which B blocks form micelles in dimethylformamide. On dialysis against an aqueous solution, the extended A blocks then associate intermolecularly to form rod-shaped micelles, which connect the B block micelles. The result is a meshed cage-like particle. The implications of these observations on the aggregation behavior of polymeric surfactants in dilute solution are discussed. Images PMID:11607245

Adaptation of red blood cell lysis represents a fundamental breakthrough that improves the sensitivity of Salmonella detection in blood

PubMed Central

Boyd, MA; Tennant, SM; Melendez, JH; Toema, D; Galen, JE; Geddes, CD; Levine, MM

2015-01-01

Aims Isolation of Salmonella Typhi from blood culture is the standard diagnostic for confirming typhoid fever but it is unavailable in many developing countries. We previously described a Microwave Accelerated Metal Enhanced Fluorescence (MAMEF)-based assay to detect Salmonella in medium. Attempts to detect Salmonella in blood were unsuccessful, presumably due to the interference of erythrocytes. The objective of this study was to evaluate various blood treatment methods that could be used prior to PCR, real-time PCR or MAMEF to increase sensitivity of detection of Salmonella. Methods and Results We tested ammonium chloride and erythrocyte lysis buffer, water, Lymphocyte Separation Medium, BD Vacutainer® CPT™ Tubes and dextran. Erythrocyte lysis buffer was the best isolation method as it is fast, inexpensive and works with either fresh or stored blood. The sensitivity of PCR- and real-time PCR detection of Salmonella in spiked blood was improved when whole blood was first lysed using erythrocyte lysis buffer prior to DNA extraction. Removal of erythrocytes and clotting factors also enabled reproducible lysis of Salmonella and fragmentation of DNA, which are necessary for MAMEF sensing. Conclusions Use of the erythrocyte lysis procedure prior to DNA extraction has enabled improved sensitivity of Salmonella detection by PCR and real-time PCR and has allowed lysis and fragmentation of Salmonella using microwave radiation (for future detection by MAMEF). Significance and Impact of the Study Adaptation of the blood lysis method represents a fundamental breakthrough that improves the sensitivity of DNA-based detection of Salmonella in blood. PMID:25630831

Comparison of Four Nuclear Isolation Buffers for Plant DNA Flow Cytometry

PubMed Central

LOUREIRO, JOÃO; RODRIGUEZ, ELEAZAR; DOLEŽEL, JAROSLAV; SANTOS, CONCEIÇÃO

2006-01-01

• Background and Aims DNA flow cytometry requires preparation of suspensions of intact nuclei, which are stained using a DNA-specific fluorochrome prior to analysis. Various buffer formulas were developed to preserve nuclear integrity, protect DNA from degradation and facilitate its stoichiometric staining. Although nuclear isolation buffers differ considerably in chemical composition, no systematic comparison of their performance has been made until now. This knowledge is required to select the appropriate buffer for a given species and tissue. • Methods Four common lysis buffers (Galbraith's, LB01, Otto's and Tris.MgCl2) were used to prepare samples from leaf tissues of seven plant species (Sedum burrito, Oxalis pes-caprae, Lycopersicon esculentum, Celtis australis, Pisum sativum, Festuca rothmaleri and Vicia faba). The species were selected to cover a wide range of genome sizes (1·30–26·90 pg per 2C DNA) and a variety of leaf tissue types. The following parameters were assessed: forward (FS) and side (SS) light scatters, fluorescence of propidium iodide-stained nuclei, coefficient of variation of DNA peaks, presence of debris background and the number of nuclei released from sample tissue. The experiments were performed independently by two operators and repeated on three different days. • Key Results Clear differences among buffers were observed. With the exception of O. pes-caprae, any buffer provided acceptable results for all species. LB01 and Otto's were generally the best buffers, with Otto's buffer providing better results in species with low DNA content. Galbraith's buffer led to satisfactory results and Tris.MgCl2 was generally the worst, although it yielded the best histograms in C. australis. A combined analysis of FS and SS provided a ‘fingerprint’ for each buffer. The variation between days was more significant than the variation between operators. • Conclusions Each lysis buffer tested responded to a specific problem differently and none of the buffers worked best with all species. These results expand our knowledge on nuclear isolation buffers and will facilitate selection of the most appropriate buffer depending on species, tissue type and the presence of cytosolic compounds interfering with DNA staining. PMID:16820407

P/Q-type calcium channels activate neighboring calcium-dependent potassium channels in mouse motor nerve terminals.

PubMed

Protti, D A; Uchitel, O D

1997-08-01

The identity of the voltage-dependent calcium channels (VDCC), which trigger the Ca2+-gated K+ currents (IK(Ca)) in mammalian motor nerve terminals, was investigated by means of perineurial recordings. The effects of Ca2+ chelators with different binding kinetics on the activation of IK(Ca) were also examined. The calcium channel blockers of the P/Q family, omega-agatoxin IVA (omega-Aga-IVA) and funnel-web spider toxin (FTX), have been shown to exert a strong blocking effect on IK(Ca). In contrast, nitrendipine and omega-conotoxin GVIA (omega-CgTx) did not affect the Ca2+-activated K+ currents. The intracellular action of the fast Ca2+ buffers BAPTA and DM-BAPTA prevented the activation of the IK(Ca), while the slow Ca2+ buffer EGTA was ineffective at blocking it. These data indicate that P/Q-type VDCC mediate the Ca2+ influx which activates IK(Ca). The spatial association between Ca2+ and Ca2+-gated K+ channels is discussed, on the basis of the differential effects of the fast and slow Ca2+ chelators.

Antimicrobial susceptibility and internalization of Salmonella Typhimurium in vacuum-tumbled marinated beef products.

PubMed

Pokharel, S; Brooks, J C; Martin, J N; Brashears, M M

2016-12-01

As the incidence of multidrug resistance (MDR) Salmonella enterica serotype Typhimurium is increasing, data regarding the antimicrobial interventions and pathogen internalization in marinated meat products are important. This study evaluated the antimicrobial intervention and internalization of Salm. Typhimurium in marinated beef sirloin steaks. Beef bottom sirloin flaps (IMPS #185A; USDA Select) inoculated (10 8  log 10  CFU ml -1 ) with Salm. Typhimurium were sprayed (lactic acid (4%) and buffered vinegar (2%)) prior to vacuum-tumbled marination (0·35% sodium chloride and 0·45% sodium tripolyphosphate) for 30 min. Pathogen presence after antimicrobial spray, vacuum-tumbled marination, and translocation was determined by direct plating on Xylose Lysine Deoxycholate (XLD) agar with tryptic soy agar (TSA) overlay. The data imply varied internalization and antimicrobial susceptibility pattern of Salm. Typhimurium in marinated meat. Lactic acid (4%) spray (P < 0·0001) and buffered vinegar (2%; P < 0·0001) reduced surface populations of Salm. Typhimurium on inoculated beef sirloin flaps prior to vacuum marination. However, lactic acid treated sirloin flaps had greater reductions (~2 log 10  CFU cm -2 ) than buffered vinegar when compared with control prior to vacuum marination. However, the translocation of Salm. Typhimurium following vacuum marination was not influenced (P < 0·333) by the application of a surface organic acid spray prior to marination. As detailed in the Federal Register FSIS final rule (9 CFR part 317), vacuum-marinated, vacuum-tumbled meat products are not designated as 'mechanically tenderized'. As such, the internalization and potential survival of Salmonella spp. in marinated beef products is a major concern. These results highlight the internalization of pathogens in vacuum-tumbled meat products and emphasize the importance of considering these products as nonintact. Similarly, these data confirm the efficacy and utility of interventions prior to vacuum-tumbled marination. Further research is needed to identify additional strategies to mitigate internalization and translocation of pathogens into vacuum-marinated meat products. © 2016 The Society for Applied Microbiology.

Functional and molecular characterization of transmembrane intracellular pH regulators in human dental pulp stem cells.

PubMed

Chen, Gunng-Shinng; Lee, Shiao-Pieng; Huang, Shu-Fu; Chao, Shih-Chi; Chang, Chung-Yi; Wu, Gwo-Jang; Li, Chung-Hsing; Loh, Shih-Hurng

2018-06-01

Homeostasis of intracellular pH (pH i ) plays vital roles in many cell functions, such as proliferation, apoptosis, differentiation and metastasis. Thus far, Na + -H + exchanger (NHE), Na + -HCO 3 - co-transporter (NBC), Cl - /HCO 3 - exchanger (AE) and Cl - /OH - exchanger (CHE) have been identified to co-regulate pH i homeostasis. However, functional and biological pH i -regulators in human dental pulp stem cells (hDPSCs) have yet to be identified. Microspectrofluorimetry technique with pH-sensitive fluorescent dye, BCECF, was used to detect pH i changes. NH 4 Cl and Na + -acetate pre-pulse were used to induce intracellular acidosis and alkalosis, respectively. Isoforms of pH i -regulators were detected by Western blot technique. The resting pH i was no significant difference between that in HEPES-buffered (nominal HCO 3 - -free) solution or CO 2 /HCO 3 -buffered system (7.42 and 7.46, respectively). The pH i recovery following the induced-intracellular acidosis was blocked completely by removing [Na + ] o , while only slowed (-63%) by adding HOE694 (a NHE1 specific inhibitor) in HEPES-buffered solution. The pH i recovery was inhibited entirely by removing [Na + ] o , while adding HOE 694 pulse DIDS (an anion-transporter inhibitor) only slowed (-55%) the acid extrusion. Both in HEPES-buffered and CO 2 /HCO 3 -buffered system solution, the pH i recovery after induced-intracellular alkalosis was entirely blocked by removing [Cl - ] o . Western blot analysis showed the isoforms of pH i regulators, including NHE1/2, NBCe1/n1, AE1/2/3/4 and CHE in the hDPSCs. We demonstrate for the first time that resting pH i is significantly higher than 7.2 and meditates functionally by two Na + -dependent acid extruders (NHE and NBC), two Cl - -dependent acid loaders (CHE and AE) and one Na + -independent acid extruder(s) in hDPSCs. These findings provide novel insight for basic and clinical treatment of dentistry. Copyright © 2018 Elsevier Ltd. All rights reserved.

Endangered Species Case – Northwest Center for Alternatives to Pesticides v. EPA

EPA Pesticide Factsheets

EPA is reinstating streamside no-spray buffer zones to protect endangered or threatened Pacific salmon and steelhead in California, Oregon and Washington State, which were originally established in prior litigation brought against EPA by WTC and others.

Markov prior-based block-matching algorithm for superdimension reconstruction of porous media

NASA Astrophysics Data System (ADS)

Li, Yang; He, Xiaohai; Teng, Qizhi; Feng, Junxi; Wu, Xiaohong

2018-04-01

A superdimension reconstruction algorithm is used for the reconstruction of three-dimensional (3D) structures of a porous medium based on a single two-dimensional image. The algorithm borrows the concepts of "blocks," "learning," and "dictionary" from learning-based superresolution reconstruction and applies them to the 3D reconstruction of a porous medium. In the neighborhood-matching process of the conventional superdimension reconstruction algorithm, the Euclidean distance is used as a criterion, although it may not really reflect the structural correlation between adjacent blocks in an actual situation. Hence, in this study, regular items are adopted as prior knowledge in the reconstruction process, and a Markov prior-based block-matching algorithm for superdimension reconstruction is developed for more accurate reconstruction. The algorithm simultaneously takes into consideration the probabilistic relationship between the already reconstructed blocks in three different perpendicular directions (x , y , and z ) and the block to be reconstructed, and the maximum value of the probability product of the blocks to be reconstructed (as found in the dictionary for the three directions) is adopted as the basis for the final block selection. Using this approach, the problem of an imprecise spatial structure caused by a point simulation can be overcome. The problem of artifacts in the reconstructed structure is also addressed through the addition of hard data and by neighborhood matching. To verify the improved reconstruction accuracy of the proposed method, the statistical and morphological features of the results from the proposed method and traditional superdimension reconstruction method are compared with those of the target system. The proposed superdimension reconstruction algorithm is confirmed to enable a more accurate reconstruction of the target system while also eliminating artifacts.

Pre-flight report on cultured human embryonic kidney cell handling and cell electrophoresis. Prepared prior to continuous-flow electrophoretic separation experiments aboard space shuttle flight STS-8

NASA Technical Reports Server (NTRS)

Todd, P. W.; Sarnoff, B. E.; Li, Z. K.

1985-01-01

Studies of the physical properties of continuous-flow zero-G electrophoretic separator (CFES) buffer, the electrokinetic properties of human erythrocytes in the CFES buffer, the electrokinetic properties of human embryonic kidney cells in the CFES buffer, and the viability and yield of human embryonc kidney cells subjected to flight handling procedures are discussed. In general, the procedure for cell handling and electrophoresis of HEK-8514 cells in 1st or 2nd passage on STS-8 is acceptable if executed properly. The CFES buffer has ionic strength that is barely compatible with cell viability and membrane stability, as seen in experiments with human erythrocytes and trypan-blue staining of human kidney cells. Cells suspended in 10% dialysed horse serum for 3 days in the cold appear to be more stable than freshly trypsinized cells. 10% horse serum appears to be superior to 5% horse serum for this purpose. The mean absolute raw mobility of HEK-8514 cells in CFES buffer at 6 degrees, conductivity 0.055 mmho/cm, is 1.1 to 1.4 um-cm/V-sec, with a range of nearly a whole mobility unit.

High quality Ge epilayer on Si (1 0 0) with an ultrathin Si1-x Ge x /Si buffer layer by RPCVD

NASA Astrophysics Data System (ADS)

Chen, Da; Guo, Qinglei; Zhang, Nan; Xu, Anli; Wang, Bei; Li, Ya; Wang, Gang

2017-07-01

The authors report a method to grow high quality strain-relaxed Ge epilayer on a combination of low temperature Ge seed layer and Si1-x Ge x /Si superlattice buffer layer by reduced pressure chemical vapor deposition system without any subsequent annealing treatment. Prior to the growth of high quality Ge epilayer, an ultrathin Si1-x Ge x /Si superlattice buffer layer with the thickness of 50 nm and a 460 nm Ge seed layer were deposited successively at low temperature. Then an 840 nm Ge epilayer was grown at high deposition rate with the surface root-mean-square roughness of 0.707 nm and threading dislocation density of 2.5  ×  106 cm-2, respectively. Detailed investigations of the influence of ultrathin low-temperature Si1-x Ge x /Si superlattice buffer layer on the quality of Ge epilayer were performed, which indicates that the crystalline quality of Ge epilayer can be significantly improved by enhancing the Ge concentration of Si1-x Ge x /Si superlattice buffer layer.

Do social relationships buffer the effects of widowhood? A prospective study of adaptation to the loss of a spouse.

PubMed

Anusic, Ivana; Lucas, Richard E

2014-10-01

The idea that strong social relationships can buffer the negative effects of stress on well-being has received much attention in existing literature. However, previous studies have used less than ideal research designs to test this hypothesis, making it difficult to draw firm conclusions regarding the buffering effects of social support. In this study, we examined the buffering hypothesis in the context of reaction and adaptation to widowhood in three large longitudinal datasets. We tested whether social relationships moderated reaction and adaptation to widowhood in samples of people who experienced loss of a spouse from three longitudinal datasets of nationally representative samples from Germany (N = 1,195), Great Britain (N = 562), and Australia (N = 298). We found no evidence that social relationships established before widowhood buffered either reaction or adaptation to the death of one's spouse. Similarly, social relationships that were in place during the first year of widowhood did not help widows and widowers recover from this difficult event. Social relationships acquired prior to widowhood, or those available in early stages of widowhood, do not appear to explain individual differences in adaptation to loss. © 2013 Wiley Periodicals, Inc.

Do Social Relationships Buffer the Effects of Widowhood? A Prospective Study of Adaptation to the Loss of a Spouse

PubMed Central

Anusic, Ivana; Lucas, Richard E.

2013-01-01

Objective The idea that strong social relationships can buffer the negative effects of stresson well-being has received much attention in existing literature. However, previous studies have used less than ideal research designs to test this hypothesis, making it difficult to draw firm conclusions regarding these buffering effects. In this study we examined the buffering hypothesis in the context of reaction and adaptation to widowhood in three large longitudinal datasets. Method We tested whether social relationships moderated reaction and adaptation to widowhood in samples of people who experienced loss of spouse from three longitudinal datasets of nationally representative samples from Germany (N = 1,195), Britain (N = 562), and Australia (N = 298). Results We found no evidence that social relationships established before widowhood buffered either reaction or adaptation to death of one's spouse. Similarly, social relationships that were in place during the first year of widowhood did not help widows and widowers recover from this difficult event. Conclusions Social relationships acquired prior to widowhood, or those available in early stages of widowhood do not appear to explain individual differences in adaptation to loss. PMID:24033325

Banking for the future: an Australian experience in brain banking.

PubMed

Sarris, M; Garrick, T M; Sheedy, D; Harper, C G

2002-06-01

The New South Wales (NSW) Tissue Resource Centre (TRC) has been set up to provide Australian and international researchers with fixed and frozen brain tissue from cases that are well characterised, both clinically and pathologically, for projects related to neuropsychiatric and alcohol-related disorders. A daily review of the Department of Forensic Medicine provides initial information regarding a potential collection. If the case adheres to the strict inclusion criteria, the pathologist performing the postmortem examination is approached regarding retention of the brain tissue. The next of kin of the deceased is then contacted requesting permission to retain the brain for medical research. Cases are also obtained through donor programmes, where donors are assessed and consent to donate their brain during life. Once the brain is removed at autopsy, the brain is photographed, weighed and the volume determined, the brainstem and cerebellum are removed. The two hemispheres are divided, one hemisphere is fresh frozen and one fixed (randomised). Prior to freezing, the hemisphere is sliced into 1-cm coronal slices and a set of critical area blocks is taken. All frozen tissues are kept bagged at -80 degrees C. The other hemisphere is fixed in 15% buffered formalin for 2 weeks, embedded in agar and sliced at 3-mm intervals in the coronal plane. Tissue blocks from these slices are used for neuropathological analysis to exclude any other pathology. The TRC currently has 230 cases of both fixed and frozen material that has proven useful in a range of techniques in many research projects. These techniques include quantitative analyses of brain regions using neuropathological, neurochemical, neuropharmacological and gene expression assays.

Modeling early in situ wetting of a compacted bentonite buffer installed in low permeable crystalline bedrock

NASA Astrophysics Data System (ADS)

Dessirier, B.; Frampton, A.; Fransson, À.; Jarsjö, J.

2016-08-01

The repository concept for geological disposal of spent nuclear fuel in Sweden and Finland is planned to be constructed in sparsely fractured crystalline bedrock and with an engineered bentonite buffer to embed the waste canisters. An important stage in such a deep repository is the postclosure phase following the deposition and the backfilling operations when the initially unsaturated buffer material gets hydrated by the groundwater delivered by the natural bedrock. We use numerical simulations to interpret observations on buffer wetting gathered during an in situ campaign, the Bentonite Rock Interaction Experiment, in which unsaturated bentonite columns were introduced into deposition holes in the floor of a 417 m deep tunnel at the Äspö Hard Rock Laboratory in Sweden. Our objectives are to assess the performance of state-of-the-art flow models in reproducing the buffer wetting process and to investigate to which extent dependable predictions of buffer wetting times and saturation patterns can be made based on information collected prior to buffer insertion. This would be important for preventing insertion into unsuitable bedrock environments. Field data and modeling results indicate the development of a de-saturated zone in the rock and show that in most cases, the presence or absence of fractures and flow heterogeneity are more important factors for correct wetting predictions than the total inflow. For instance, for an equal open-hole inflow value, homogeneous inflow yields much more rapid buffer wetting than cases where fractures are represented explicitly thus creating heterogeneous inflow distributions.

k(+)-buffer: An Efficient, Memory-Friendly and Dynamic k-buffer Framework.

PubMed

Vasilakis, Andreas-Alexandros; Papaioannou, Georgios; Fudos, Ioannis

2015-06-01

Depth-sorted fragment determination is fundamental for a host of image-based techniques which simulates complex rendering effects. It is also a challenging task in terms of time and space required when rasterizing scenes with high depth complexity. When low graphics memory requirements are of utmost importance, k-buffer can objectively be considered as the most preferred framework which advantageously ensures the correct depth order on a subset of all generated fragments. Although various alternatives have been introduced to partially or completely alleviate the noticeable quality artifacts produced by the initial k-buffer algorithm in the expense of memory increase or performance downgrade, appropriate tools to automatically and dynamically compute the most suitable value of k are still missing. To this end, we introduce k(+)-buffer, a fast framework that accurately simulates the behavior of k-buffer in a single rendering pass. Two memory-bounded data structures: (i) the max-array and (ii) the max-heap are developed on the GPU to concurrently maintain the k-foremost fragments per pixel by exploring pixel synchronization and fragment culling. Memory-friendly strategies are further introduced to dynamically (a) lessen the wasteful memory allocation of individual pixels with low depth complexity frequencies, (b) minimize the allocated size of k-buffer according to different application goals and hardware limitations via a straightforward depth histogram analysis and (c) manage local GPU cache with a fixed-memory depth-sorting mechanism. Finally, an extensive experimental evaluation is provided demonstrating the advantages of our work over all prior k-buffer variants in terms of memory usage, performance cost and image quality.

Treatment of coking wastewater by a novel electric assisted micro-electrolysis filter.

PubMed

Xie, Ruosong; Wu, Miaomiao; Qu, Guangfei; Ning, Ping; Cai, Yingying; Lv, Pei

2018-04-01

A newly designed electric assisted micro-electrolysis filter (E-ME) was developed to investigate its degradation efficiency for coking wastewater and correlated characteristics. The performance of the E-ME system was compared with separate electrolysis (SE) and micro-electrolysis (ME) systems. The results showed a prominent synergistic effect on COD removal in E-ME systems. Gas chromatography/mass spectrometry (GC-MS) analysis confirmed that the applied electric field enhanced the degradation of phenolic compounds. Meanwhile, more biodegradable oxygen-bearing compounds were detected. SEM images of granular activated carbon (GAC) showed that inactivation and blocking were inhibited during the E-ME process. The effects of applied voltage and initial pH in E-ME systems were also studied. The best voltage value was 1V, but synergistic effects existed even with lower applied voltage. E-ME systems exhibited some pH buffering capacity and attained the best efficiency in neutral media, which means that there is no need to adjust pH prior to or during the treatment process. Therefore, E-ME systems were confirmed as a promising technology for treatment of coking wastewater and other refractory wastewater. Copyright © 2017. Published by Elsevier B.V.

Low Elevation Old Channel Features of the Willamette River Floodplain Support High Subsurface Denitrification Rates

EPA Science Inventory

Background/Question/Methods: Large river floodplains are poor nitrate pollution buffers when polluted groundwater moves beneath biogeochemically retentive zones prior to entering the main channel. However, in floodplain regions with extensive backwaters and organic carbon acc...

Assessment of pancreas cells

NASA Technical Reports Server (NTRS)

Vanoss, C. J.

1978-01-01

Pancreatic islets were obtained from guinea pig pancreas by the collagenase method and kept alive in tissue culture prior to further studies. Pancreas cell morphology was studied by standard histochemical techniques using light microscopy. Preparative vertical electrophoresis-levitation of dispersed fetal guinea pig pancreas cells was conducted in phosphate buffer containing a heavy water (D20) gradient which does not cause clumping of cells or alter the osmolarity of the buffers. The faster migrating fractions tended to be enriched in beta-cell content. Alpha and delta cells were found to some degree in most fractions. A histogram showing the cell count distribution is included.

Study Skills Package: Development and Evaluation

DTIC Science & Technology

1980-03-01

It was concluded that the Instructor Orientation and Training was at least moderately successful in promoting the remediation of study skills...them comparable across successive blocks. Thus, each student’s block times and block scores for the pretreatment time period (prior to being assigned... successful in promoting the remediation of student study skill problems--a finding further substantiated by the consistent improve- ments in student block

Secure Infant-Mother Attachment Buffers the Effect of Early-Life Stress on Age of Menarche.

PubMed

Sung, Sooyeon; Simpson, Jeffry A; Griskevicius, Vladas; Kuo, Sally I-Chun; Schlomer, Gabriel L; Belsky, Jay

2016-05-01

Prior research indicates that being reared in stressful environments is associated with earlier onset of menarche in girls. In this research, we examined (a) whether these effects are driven by exposure to certain dimensions of stress (harshness or unpredictability) during the first 5 years of life and (b) whether the negative effects of stress on the timing of menarche are buffered by secure infant-mother attachment. Results revealed that (a) exposure to greater harshness (but not unpredictability) during the first 5 years of life predicted earlier menarche and (b) secure infant-mother attachment buffered girls from this effect of harsh environments. By connecting attachment research to its evolutionary foundations, these results illuminate how environmental stressors and relationships early in life jointly affect pubertal timing. © The Author(s) 2016.

Concentrations and behavior of oxygen and oxide ion in melts of composition CaO.MgO.xSiO2

NASA Technical Reports Server (NTRS)

Semkow, K. W.; Haskin, L. A.

1985-01-01

The behavior of oxygen and oxide ion in silicate melts was investigated through their electrochemical reactions at a platinum electrode. Values are given for the diffusion coefficient for molecular oxygen in diopside melt and the activation energy of diffusion. It is shown that molecular oxygen dissociates prior to undergoing reduction and that oxide ion reacts quickly with silicate polymers when it is produced. The concentration of oxide ion is kept low by a buffering effect of the silicate, the exact level being dependent on the silicate composition. Data on the kinetics of reaction of the dissociation of molecular oxygen and on the buffering reactions are provided. It is demonstrated that the data on oxygen in these silicate melts are consistent with those for solid buffers.

49 CFR 231.2 - Hopper cars and high-side gondolas with fixed ends.

Code of Federal Regulations, 2010 CFR

2010-10-01

... which time they must be made to comply with the standards prescribed. (iv) Carriers are not required to... within 12 inches of a vertical plane parallel with end of car and passing through the inside face of... outer face of buffer block. (2) Carriers are not required to make changes to secure additional end...

Synthesis, pharmacology, crystal properties, and quantitative solvation studies from a drug transport perspective for three new 1,2,4-thiadiazoles.

PubMed

Perlovich, German L; Volkova, Tatyana V; Proshin, Alexey N; Sergeev, Dmitriy Yu; Bui, Cong Trinh; Petrova, Ludmila N; Bachurin, Sergey O

2010-09-01

A novel 1,2,4-thiadiazoles were synthesized. Crystal structures of these compounds were solved by X-ray diffraction experiments and comparative analysis of molecular conformational states, packing architecture, and hydrogen bonds networks were carried out. Thermodynamic aspects of sublimation processes of studied compounds were determined using temperature dependencies of vapor pressure. Thermophysical characteristics of the molecular crystals were obtained and compared with the sublimation and structural parameters. Solubility and solvation processes of 1,2,4-thiadiazoles in buffer, n-hexane and n-octanol were studied within the wide range of temperature intervals and thermodynamic functions were calculated. Specific and nonspecific interactions of molecules resolved in crystals and solvents were estimated and compared. Distribution processes of compounds in buffer/n-octanol and buffer/n-hexane systems (describing different types of membranes) were investigated. Analysis of transfer processes of studied molecules from the buffer to n-octanol/n-hexane phases was carried out by the diagram method with evaluation of the enthalpic and entropic terms. This approach allows us to design drug molecules with optimal passive transport properties. Calcium-blocking properties of the substances were evaluated.

DNA adsorption to and elution from silica surfaces: influence of amino acid buffers.

PubMed

Vandeventer, Peter E; Mejia, Jorge; Nadim, Ali; Johal, Malkiat S; Niemz, Angelika

2013-09-19

Solid phase extraction and purification of DNA from complex samples typically requires chaotropic salts that can inhibit downstream polymerase amplification if carried into the elution buffer. Amino acid buffers may serve as a more compatible alternative for modulating the interaction between DNA and silica surfaces. We characterized DNA binding to silica surfaces, facilitated by representative amino acid buffers, and the subsequent elution of DNA from the silica surfaces. Through bulk depletion experiments, we found that more DNA adsorbs to silica particles out of positively compared to negatively charged amino acid buffers. Additionally, the type of the silica surface greatly influences the amount of DNA adsorbed and the final elution yield. Quartz crystal microbalance experiments with dissipation monitoring (QCM-D) revealed multiphasic DNA adsorption out of stronger adsorbing conditions such as arginine, glycine, and glutamine, with DNA more rigidly bound during the early stages of the adsorption process. The DNA film adsorbed out of glutamate was more flexible and uniform throughout the adsorption process. QCM-D characterization of DNA elution from the silica surface indicates an uptake in water mass during the initial stage of DNA elution for the stronger adsorbing conditions, which suggests that for these conditions the DNA film is partly dehydrated during the prior adsorption process. Overall, several positively charged and polar neutral amino acid buffers show promise as an alternative to methods based on chaotropic salts for solid phase DNA extraction.

Assessing benefits and risk of using flue gas desulfurized gypsum (FGDG) as soil amendment in a Coastal Plain soil

USDA-ARS?s Scientific Manuscript database

The influence of FGDG and grass buffers on runoff water quality and corn production following poultry litter (PL) application is being evaluated as part of a regional USDA-ARS project (Auburn-AL, Oxford-MS, and Tifton-GA). Treatments at Tifton were laid out in a randomized complete block design wit...

Ca/Alq3 hybrid cathode buffer layer for the optimization of organic solar cells based on a planar heterojunction

NASA Astrophysics Data System (ADS)

El Jouad, Z.; Barkat, L.; Stephant, N.; Cattin, L.; Hamzaoui, N.; Khelil, A.; Ghamnia, M.; Addou, M.; Morsli, M.; Béchu, S.; Cabanetos, C.; Richard-Plouet, M.; Blanchard, P.; Bernède, J. C.

2016-11-01

Use of efficient anode cathode buffer layer (CBL) is crucial to improve the efficiency of organic photovoltaic cells. Here we show that using a double CBL, Ca/Alq3, allows improving significantly cell performances. The insertion of Ca layer facilitates electron harvesting and blocks hole collection, leading to improved charge selectivity and reduced leakage current, whereas Alq3 blocks excitons. After optimisation of this Ca/Alq3 CBL using CuPc as electron donor, it is shown that it is also efficient when SubPc is substituted to CuPc in the cells. In that case we show that the morphology of the SubPc layer, and therefore the efficiency of the cells, strongly depends on the deposition rate of the SubPc film. It is necessary to deposit slowly (0.02 nm/s) the SubPc films because at higher deposition rate (0.06 nm/s) the films are porous, which induces leakage currents and deterioration of the cell performances. The SubPc layers whose formations are kinetically driven at low deposition rates are more uniform, whereas those deposited faster exhibit high densities of pinholes.

An optimized immunohistochemistry protocol for detecting the guidance cue Netrin-1 in neural tissue.

PubMed

Salameh, Samer; Nouel, Dominique; Flores, Cecilia; Hoops, Daniel

2018-01-01

Netrin-1, an axon guidance protein, is difficult to detect using immunohistochemistry. We performed a multi-step, blinded, and controlled protocol optimization procedure to establish an efficient and effective fluorescent immunohistochemistry protocol for characterizing Netrin-1 expression. Coronal mouse brain sections were used to test numerous antigen retrieval methods and combinations thereof in order to optimize the stain quality of a commercially available Netrin-1 antibody. Stain quality was evaluated by experienced neuroanatomists for two criteria: signal intensity and signal-to-noise ratio. After five rounds of testing protocol variants, we established a modified immunohistochemistry protocol that produced a Netrin-1 signal with good signal intensity and a high signal-to-noise ratio. The key protocol modifications are as follows: •Use phosphate buffer (PB) as the blocking solution solvent.•Use 1% sodium dodecyl sulfate (SDS) treatment for antigen retrieval. The original protocol was optimized for use with the Netrin-1 antibody produced by Novus Biologicals. However, we subsequently further modified the protocol to work with the antibody produced by Abcam. The Abcam protocol uses PBS as the blocking solution solvent and adds a citrate buffer antigen retrieval step.

Effects of frequent oral hygiene instructions on microbial levels and salivary buffer capacity in orthodontic patients and their parents.

PubMed

Katz-Sagi, Hadas; Redlich, Meir; Shapira, Joseph; Peretz, Benjamin; Steinberg, Doron

2008-01-01

To assess whether parental involvement can improve children's oral health as a strategiy to reduce caries risk in children undergoing orthodontic treatment. The study population consisted of 40 healthy children aged 7 to 15 years (mean 10.93 ± 2.78) and their accompanying parents (mother or father). Oral hygiene instructions were given simultaneously to all children and accompanying parents every 6 weeks at their regular orthodontic appointments. Levels of Streptococcus mutans and salivary buffer capacity were assessed for both children and parents before and 9 months into orthodontic treatment. The majority of children (74%) and parents (92%) expressed unchanged levels of Streptococcus mutans and stable salivary buffer capacity throughout the study. When analyzing child-parent pairs with respect to Streptococcus mutans and salivary buffer capacity, no significant differences were found prior to treatment. Nine months into treatment, 57% of the children and parents still showed similar Streptococcus mutans counts and buffer capacity. The child-parent approach succeeded in preventing deterioration of children's oral hygiene. Parental involvement has an essential part in maintaining children's oral health. Oral health care professionals should partner with parents when implementing any kind of health behavior. COPYRIGHT © 2008 BY QUINTESSENCE PUBLISHING CO, INC.

Design and analysis of multihypothesis motion-compensated prediction (MHMCP) codec for error-resilient visual communications

NASA Astrophysics Data System (ADS)

Kung, Wei-Ying; Kim, Chang-Su; Kuo, C.-C. Jay

2004-10-01

A multi-hypothesis motion compensated prediction (MHMCP) scheme, which predicts a block from a weighted superposition of more than one reference blocks in the frame buffer, is proposed and analyzed for error resilient visual communication in this research. By combining these reference blocks effectively, MHMCP can enhance the error resilient capability of compressed video as well as achieve a coding gain. In particular, we investigate the error propagation effect in the MHMCP coder and analyze the rate-distortion performance in terms of the hypothesis number and hypothesis coefficients. It is shown that MHMCP suppresses the short-term effect of error propagation more effectively than the intra refreshing scheme. Simulation results are given to confirm the analysis. Finally, several design principles for the MHMCP coder are derived based on the analytical and experimental results.

Preparation of arrays of long carbon nanotubes using catalyst structure

DOEpatents

Zhu, Yuntian T.; Arendt, Paul; Li, Qingwen; Zhang, Xiefie

2016-03-22

A structure for preparing an substantially aligned array of carbon nanotubes include a substrate having a first side and a second side, a buffer layer on the first side of the substrate, a catalyst on the buffer layer, and a plurality of channels through the structure for allowing a gaseous carbon source to enter the substrate at the second side and flow through the structure to the catalyst. After preparing the array, a fiber of carbon nanotubes may be spun from the array. Prior to spinning, the array can be immersed in a polymer solution. After spinning, the polymer can be cured.

High-throughput method for optimum solubility screening for homogeneity and crystallization of proteins

DOEpatents

Kim, Sung-Hou [Moraga, CA; Kim, Rosalind [Moraga, CA; Jancarik, Jamila [Walnut Creek, CA

2012-01-31

An optimum solubility screen in which a panel of buffers and many additives are provided in order to obtain the most homogeneous and monodisperse protein condition for protein crystallization. The present methods are useful for proteins that aggregate and cannot be concentrated prior to setting up crystallization screens. A high-throughput method using the hanging-drop method and vapor diffusion equilibrium and a panel of twenty-four buffers is further provided. Using the present methods, 14 poorly behaving proteins have been screened, resulting in 11 of the proteins having highly improved dynamic light scattering results allowing concentration of the proteins, and 9 were crystallized.

40 CFR 146.92 - Injection well plugging.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Injection well plugging. 146.92... to Class VI Wells § 146.92 Injection well plugging. (a) Prior to the well plugging, the owner or operator must flush each Class VI injection well with a buffer fluid, determine bottomhole reservoir...

Apoptosis and Tumor Progressionin Prostate Cancer

DTIC Science & Technology

2005-02-01

control. Proc Natl Acad Sci USA 94: 10057- 10062 . 5. Colombel M, Symmans F, et al. (1993): Detection of the apoptosis-suppressing oncoprotein bcl-2 in...hours prior to treatment. After treatment, cells were washed with phosphate buffered saline ( PBS ) and fixed in 500 [tL 0.2% glutaraldehyde in water for

Wavelength assignment algorithm considering the state of neighborhood links for OBS networks

NASA Astrophysics Data System (ADS)

Tanaka, Yu; Hirota, Yusuke; Tode, Hideki; Murakami, Koso

2005-10-01

Recently, Optical WDM technology is introduced into backbone networks. On the other hand, as the future optical switching scheme, Optical Burst Switching (OBS) systems become a realistic solution. OBS systems do not consider buffering in intermediate nodes. Thus, it is an important issue to avoid overlapping wavelength reservation between partially interfered paths. To solve this problem, so far, the wavelength assignment scheme which has priority management tables has been proposed. This method achieves the reduction of burst blocking probability. However, this priority management table requires huge memory space. In this paper, we propose a wavelength assignment algorithm that reduces both the number of priority management tables and burst blocking probability. To reduce priority management tables, we allocate and manage them for each link. To reduce burst blocking probability, our method announces information about the change of their priorities to intermediate nodes. We evaluate its performance in terms of the burst blocking probability and the reduction rate of priority management tables.

Minocycline and doxycycline, but not other tetracycline-derived compounds, protect liver cells from chemical hypoxia and ischemia/reperfusion injury by inhibition of the mitochondrial calcium uniporter

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

Schwartz, Justin; Holmuhamedov, Ekhson; Zhang, Xun

Minocycline, a tetracycline-derived compound, mitigates damage caused by ischemia/reperfusion (I/R) injury. Here, 19 tetracycline-derived compounds were screened in comparison to minocycline for their ability to protect hepatocytes against damage from chemical hypoxia and I/R injury. Cultured rat hepatocytes were incubated with 50 μM of each tetracycline-derived compound 20 min prior to exposure to 500 μM iodoacetic acid plus 1 mM KCN (chemical hypoxia). In other experiments, hepatocytes were incubated in anoxic Krebs–Ringer–HEPES buffer at pH 6.2 for 4 h prior to reoxygenation at pH 7.4 (simulated I/R). Tetracycline-derived compounds were added 20 min prior to reperfusion. Ca{sup 2+} uptake wasmore » measured in isolated rat liver mitochondria incubated with Fluo-5N. Cell killing after 120 min of chemical hypoxia measured by propidium iodide (PI) fluorometry was 87%, which decreased to 28% and 42% with minocycline and doxycycline, respectively. After I/R, cell killing at 120 min decreased from 79% with vehicle to 43% and 49% with minocycline and doxycycline. No other tested compound decreased killing. Minocycline and doxycycline also inhibited mitochondrial Ca{sup 2+} uptake and suppressed the Ca{sup 2+}-induced mitochondrial permeability transition (MPT), the penultimate cause of cell death in reperfusion injury. Ru360, a specific inhibitor of the mitochondrial calcium uniporter (MCU), also decreased cell killing after hypoxia and I/R and blocked mitochondrial Ca{sup 2+} uptake and the MPT. Other proposed mechanisms, including mitochondrial depolarization and matrix metalloprotease inhibition, could not account for cytoprotection. Taken together, these results indicate that minocycline and doxycycline are cytoprotective by way of inhibition of MCU. - Highlights: • Minocycline and doxycycline are the only cytoprotective tetracyclines of those tested • Cytoprotective tetracyclines inhibit the MPT and mitochondrial calcium and iron uptake. • Cytoprotective tetracyclines protect by inhibiting the MCU.« less

Transversus abdominal plane (TAP) block for postoperative pain management: a review.

PubMed

Jakobsson, Jan; Wickerts, Liselott; Forsberg, Sune; Ledin, Gustaf

2015-01-01

Transversus abdominal plane (TAP) block has a long history and there is currently extensive clinical experience around TAP blocks. The aim of this review is to provide a summary of the present evidence on the effects of TAP block and to provide suggestions for further studies. There are several approaches to performing abdominal wall blocks, with the rapid implementation of ultrasound-guided technique facilitating a major difference in TAP block performance. During surgery, an abdominal wall block may also be applied by the surgeon from inside the abdominal cavity. Today, there are more than 11 meta-analyses providing a compiled evidence base around the effects of TAP block. These analyses include different procedures, different techniques of TAP block administration and, importantly, they compare the TAP block with a variety of alternative analgesic regimes. The effects of TAP block during laparoscopic cholecystectomy seem to be equivalent to local infiltration analgesia and also seem to be beneficial during laparoscopic colon resection. The effects of TAP are more pronounced when it is provided prior to surgery and these effects are local anaesthesia dose-dependent. TAP block seems an interesting alternative in patients with, for example, severe obesity where epidural or spinal anaesthesia/analgesia is technically difficult and/or poses a risk. There is an obvious need for further high-quality studies comparing TAP block prior to surgery with local infiltration analgesia, single-shot spinal analgesia, and epidural analgesia. These studies should be procedure-specific and the effects should be evaluated, both regarding short-term pain and analgesic requirement and also including the effects on postoperative nausea and vomiting, recovery of bowel function, ambulation, discharge, and protracted recovery outcomes (assessed by e.g., postoperative quality of recovery scale).

Translation and rotation of small crustal blocks in the southernmost Atlantic-Weddell Sea region prior to seafloor spreading: in search of a mechanism

NASA Astrophysics Data System (ADS)

Dalziel, I. W. D.; Norton, I. O.; Lawver, L. A.; Lavier, L.; Davis, J. K.; Gahagan, L.

2016-12-01

Geological and paleomagnetic data indicate that initial fragmentation of the Gondwanaland supercontinent in the southernmost Atlantic-Weddell Sea region involved translation and rotation of two small crustal blocks. The Falkland/Malvinas block on the South American plate (F/M) and the Ellsworth-Whitmore mountains block in West Antarctica (EWM) both contain segments of the earliest Mesozoic Gondwana fold belt. The blocks originated in the Natal embayment between the Cape Mountains of southernmost Africa and the Pensacola Mountains of the East Antarctic craton margin. Shortly after emplacement of the Karoo-Ferrar large igneous province (LIP) at ca. 182Ma, the F/M block was rotated clockwise 150 ° and the EWM block counter¬clockwise 90°, while both were translated several hundred kilometers towards the Panthalassic/Pacific Ocean. As indicated by absence of shortening in the sedimentary basins of the F/M Plateau and Weddell embayment, the motions of the crustal blocks relative to the major continents happened during extreme extension accompanied by widespread silicic magmatism that preceded seafloor spreading. We propose a new reconstruction of the Gondwana craton margin, suggesting an original embayment between the Kalahari and East Antarctic cratons, and subsequent mirror-image clockwise (South America-F/M) and counterclockwise (Antarctic Peninsula-EWM) rotations prior to seafloor spreading in the Weddell Sea and South Atlantic.What geodynamic processes were involved in the significant rotations and translations of continental lithosphere prior to ocean basin formation? Our conclusion, based on the geologic and geophysical data and on geodynamic modeling, is that the motions were driven by the distributed crustal thinning of warm continental lithosphere and by mantle flow towards a retreating Panthalassic margin subduction zone associated with the formation of the Karoo-Ferrar Large Igneous Province between the East Antarctic, Kalahari and Rio de la Plata cratons.

Cortical sources of ERP in prosaccade and antisaccade eye movements using realistic source models

PubMed Central

Richards, John E.

2013-01-01

The cortical sources of event-related-potentials (ERP) using realistic source models were examined in a prosaccade and antisaccade procedure. College-age participants were presented with a preparatory interval and a target that indicated the direction of the eye movement that was to be made. In some blocks a cue was given in the peripheral location where the target was to be presented and in other blocks no cue was given. In Experiment 1 the prosaccade and antisaccade trials were presented randomly within a block; in Experiment 2 procedures were compared in which either prosaccade and antisaccade trials were mixed in the same block, or trials were presented in separate blocks with only one type of eye movement. There was a central negative slow wave occurring prior to the target, a slow positive wave over the parietal scalp prior to the saccade, and a parietal spike potential immediately prior to saccade onset. Cortical source analysis of these ERP components showed a common set of sources in the ventral anterior cingulate and orbital frontal gyrus for the presaccadic positive slow wave and the spike potential. In Experiment 2 the same cued- and non-cued blocks were used, but prosaccade and antisaccade trials were presented in separate blocks. This resulted in a smaller difference in reaction time between prosaccade and antisaccade trials. Unlike the first experiment, the central negative slow wave was larger on antisaccade than on prosaccade trials, and this effect on the ERP component had its cortical source primarily in the parietal and mid-central cortical areas contralateral to the direction of the eye movement. These results suggest that blocked prosaccade and antisaccade trials results in preparatory or set effects that decreases reaction time, eliminates some cueing effects, and is based on contralateral parietal-central brain areas. PMID:23847476

A Phase 4, multicentre, randomized, single-blind clinical trial to evaluate the immunogenicity of the live, attenuated, oral rotavirus vaccine (116E), ROTAVAC®, administered simultaneously with or without the buffering agent in healthy infants in India.

PubMed

Ella, Raches; Bobba, Radhika; Muralidhar, Sanjay; Babji, Sudhir; Vadrevu, Krishna Mohan; Bhan, Maharaj Kishan

2018-03-15

The World Health Organization recommends that rotavirus vaccines should be included in all national immunization programs. Some currently licensed oral rotavirus vaccines contain a buffering agent (either as part of a ready-to-use liquid formulation or added during reconstitution) to reduce possible degradation of the vaccine virus in the infant gut, which poses several programmatic challenges (the large dose volume or the reconstitution requirement) during vaccine administration. Because ROTAVAC®, a WHO prequalified vaccine, was derived from the 116E neonatal strain, we evaluated the immunogenicity and safety of ROTAVAC® without buffer and ROTAVAC® with buffer in a phase 4, multicentre, single-blind, randomized clinical trial in healthy infants in India. 900 infants, approximately 6, 10 and 14 weeks of age, were assigned to 3 groups to receive ROTAVAC® (0.5 mL dose) orally: (i) 2.5 mL of citrate-bicarbonate buffer 5 minutes prior to administration of ROTAVAC® (Group I), (ii) ROTAVAC®, alone, without any buffer (Group II), or (iii) ROTAVAC®, mixed with buffer immediately before administration (Group III). Non-inferiority was compared among the groups for differences in serological responses (detected by serum anti-rotavirus IgA) and safety. Geometric mean titers post vaccination at day 84 (28 days after dose 3) were 19.6 (95%CI: 17.0, 22.7), 20.7 (95%CI: 17.9, 24) and 19.2 (95%CI: 16.8, 22.1) for groups I, II and III respectively. Further, seroconversion rates and distribution of adverse events were similar among groups. Administration of ROTAVAC® at a 0.5 mL dose volume without buffering agent was shown to be well tolerated and immunogenic. Given the homologous nature of the strain, it is plausible that ROTAVAC® replicates well and confers immunity even without buffer administration.

Prior exposure to a reverberant listening environment improves speech intelligibility in adult cochlear implant listeners.

PubMed

Srinivasan, Nirmal Kumar; Tobey, Emily A; Loizou, Philipos C

2016-01-01

The goal of this study is to investigate whether prior exposure to reverberant listening environment improves speech intelligibility of adult cochlear implant (CI) users. Six adult CI users participated in this study. Speech intelligibility was measured in five different simulated reverberant listening environments with two different speech corpuses. Within each listening environment, prior exposure was varied by either having the same environment across all trials (blocked presentation) or having different environment from trial to trial (unblocked). Speech intelligibility decreased as reverberation time increased. Although substantial individual variability was observed, all CI listeners showed an increase in the blocked presentation condition as compared to the unblocked presentation condition for both speech corpuses. Prior listening exposure to a reverberant listening environment improves speech intelligibility in adult CI listeners. Further research is required to understand the underlying mechanism of adaptation to listening environment.

Prototype repository: A full scale experiment at Äspö HRL

NASA Astrophysics Data System (ADS)

Johannesson, Lars-Erik; Börgesson, Lennart; Goudarzi, Reza; Sandén, Torbjörn; Gunnarsson, David; Svemar, Christer

At Äspö Hard Rock Laboratory a full scale test of the Swedish concept for disposal of nuclear waste (KBS-3V) is in progress. The Prototype Repository project consists of two sections. The installation of the first section was made during summer and autumn 2001 and the second section during spring and summer 2003. Section 1 consists of four full-scale deposition holes, copper canisters equipped with electrical heaters, bentonite buffer consisting of blocks and pellets and a deposition tunnel backfilled with a mixture of bentonite and crushed rock, ending with a concrete plug. Section 2 consists of two full-scale deposition holes with a backfilled tunnel section and ends also with a concrete plug. Altogether 84 large bentonite blocks, with a total weight of about 130 tons, were installed and more than 2000 tons of backfill material were mixed and compacted in situ. Earlier developed techniques for both manufacturing and installing the buffer and the backfill were used in the project. Measurements and data from the installation allow calculations of the expected density in the buffer and in different parts of the backfill. The bentonite buffer in deposition holes 1, 3, 5 and 6, the backfill and the surrounding rock are instrumented with gauges for measuring temperature, water pressure, total pressure, relative humidity, resistivity, canister displacement and rock stresses. The instruments are connected to data acquisition systems by cables protected by tubes. These tubes are led through the rock in watertight lead-throughs to a nearby tunnel where the data acquisition systems are situated. More than 1100 transducers have been installed in the rock, buffer and the backfill. The technique for protecting the transducers from high water and swelling pressure was developed in this and preceding projects and furthermore different designs of transducers are used for the same type of measurement in order to compare their behaviour. The deposition holes have different water inflow rates (from 0.0007 to 0.08 l/min), resulting in different water uptake rates of the buffer. The water ratio as a function of time for different parts of the buffer can be estimated from measurement of the relative humidity in the pore system of the buffer. Deposition hole 1 with a relatively high water inflow (0.08 l/min), shows in some parts of the buffer very high degree of saturation while the drier holes 2, 3, 4, 5 and 6 (0.0007-0.003 l/min) show a very slow saturation rate in most parts of the buffer. The temperature in the buffer and on the surface of the canisters is carefully studied. The temperature measurements indicate a rather large drop in temperature (approx. 10 °C) over the 10 mm gap between the canister and the buffer. In deposition hole 1 the gap has vanished due to high degree of saturation, resulting in a lower temperature on the surface of the canister. The displacement of the canisters in deposition holes 3 and 6 has been measured continuously with six transducers in each deposition hole. The measurement allows calculation of the displacement of the canisters in all three directions. The maximum measured vertical displacement so far is about 8 mm upwards. The water uptake in the backfill is measured continuously with soil psychrometers. The results indicate a high degree of saturation close to the rock wall and on top of the buffer in the deposition holes, while the backfill in the more central part of tunnel shows slow increase in water ratio over the time. Transducers for measuring suction in the rock (soil psychrometers) have been installed very close to the surface of one of the deposition holes. The transducers are measuring rather high suctions close to the rock surface, indicating a not fully saturated pore system of the rock. The paper describes the following items: the test design, the installation phase, example of measurements made during the water uptake and some preliminary evaluations of water uptake of both the buffer and backfill up to November 1, 2004. The paper is mainly focused on the engineered barriers.

DNA Adsorption to and Elution from Silica Surfaces: Influence of Amino Acid Buffers

PubMed Central

Vandeventer, Peter E.; Mejia, Jorge; Nadim, Ali; Johal, Malkiat S.; Niemz, Angelika

2014-01-01

Solid phase extraction and purification of DNA from complex samples typically requires chaotropic salts that can inhibit downstream polymerase amplification if carried into the elution buffer. Amino acid buffers may serve as a more compatible alternative for modulating the interaction between DNA and silica surfaces. We characterized DNA binding to silica surfaces, facilitated by representative amino acid buffers, and the subsequent elution of DNA from the silica surfaces. Through bulk depletion experiments, we found that more DNA adsorbs to silica particles out of positively compared to negatively charged amino acid buffers. Additionally, the type of the silica surface greatly influences the amount of DNA adsorbed, and the final elution yield. Quartz crystal microbalance experiments with dissipation monitoring (QCM-D) revealed multiphasic DNA adsorption out of stronger adsorbing conditions such as arginine, glycine, and glutamine, with DNA more rigidly bound during the early stages of the adsorption process. The DNA film adsorbed out of glutamate was more flexible and uniform throughout the adsorption process. QCM-D characterization of DNA elution from the silica surface indicates an uptake in water mass during the initial stage of DNA elution for the stronger adsorbing conditions, which suggests that for these conditions the DNA film is partly dehydrated during the prior adsorption process. Overall, several positively charged and polar neutral amino acid buffers show promise as an alternative to methods based on chaotropic salts for solid phase DNA extraction. PMID:23931415

Social stress buffering by friends in childhood and adolescence: Effects on HPA and oxytocin activity.

PubMed

Doom, Jenalee R; Doyle, Colleen M; Gunnar, Megan R

2017-02-01

Previous research has demonstrated that before puberty, parents are able to buffer, and often completely block, cortisol responses to social evaluative stressors (e.g., Trier Social Stress Test; TSST). However, after puberty, parents no longer provide a powerful buffer of the HPA axis from a social-evaluative stressor. The current study investigates whether friends can buffer the HPA axis in both children and adolescents compared to parents and whether similar stress-ameliorating patterns can also be observed in oxytocin activity. A total of 109 participants (54 children aged 9-10 and 55 adolescents aged 15-16; half of each sex) completed the TSST and were randomly assigned to prepare for their speech with their parent or friend for 5 minutes beforehand. Salivary cortisol and urinary oxytocin were measured before and after the TSST. For children, cortisol responses were comparable regardless of who helped the child prepare the speech. For adolescents, however, friends actually amplified the cortisol response compared to parents. In addition, adolescents produced less oxytocin than children, as did males compared to females. Notably, for boys, oxytocin levels decreased across the session if participants prepared with a friend rather than their parent. The mean change was in the same direction but not significant for girls. These results indicate that friends do not take over the social buffering role by age 15-16, which may inform interventions in at-risk children and adolescents.

Social Stress Buffering by Friends in Childhood and Adolescence: Effects on HPA and Oxytocin Activity

PubMed Central

Doom, Jenalee R.; Doyle, Colleen M.; Gunnar, Megan R.

2017-01-01

Previous research has demonstrated that before puberty, parents are able to buffer, and often completely block, cortisol responses to social evaluative stressors (e.g., Trier Social Stress Test; TSST). However, after puberty, parents no longer provide a powerful buffer of the HPA axis from a social-evaluative stressor. The current study investigates whether friends can buffer the HPA axis in both children and adolescents compared to parents and whether similar stress-ameliorating patterns can also be observed in oxytocin activity. A total of 109 participants (54 children ages 9–10 and 55 adolescents ages 15–16; half of each sex) completed the TSST and were randomly assigned to prepare for their speech with their parent or friend for 5 minutes beforehand. Salivary cortisol and urinary oxytocin were measured before and after the TSST. For children, cortisol responses were comparable regardless of who helped the child prepare the speech. For adolescents, however, friends actually amplified the cortisol response compared to parents. In addition, adolescents produced less oxytocin than children, as did males compared to females. Notably, for boys, oxytocin levels decreased across the session if participants prepared with a friend rather than their parent. The mean change was in the same direction but not significant for girls. These results indicate that friends do not take over the social buffering role by age 15–16, which may inform interventions in at-risk children and adolescents. PMID:26899419

Hypothalamic oxytocin mediates social buffering of the stress response

PubMed Central

Smith, Adam S.; Wang, Zuoxin

2013-01-01

Background While stressful life events can enhance the risk of mental disorders, positive social interactions can propagate good mental health and normal behavioral routines. Still, the neural systems that promote these benefits are undetermined. Oxytocin is a hormone involved in social behavior and stress; thus, we focus on the impact that social buffering has on the stress response and the governing effects of oxytocin. Methods Female prairie voles (Microtus ochrogaster) were exposed to 1 hr immobilization stress then recovered alone or with their male partner to characterize the effect of social contact on the behavioral, physiological, and neuroendocrine stress response. In addition, we treated immobilized females recovering alone with oxytocin, or vehicle, and females recovering with their male partner with a selective oxytocin receptor antagonist, or vehicle. Group sizes varied from 6 to 8 voles (n = 98 total). Results We found that 1 hr immobilization increased anxiety-like behaviors and circulating levels of corticosterone, a stress hormone, in females recovering alone, but not the females recovering with their male partner. This social buffering by the male partner on biobehavioral responses to stress was accompanied by increased oxytocin release in the paraventricular nucleus (PVN) of the hypothalamus. Intra-PVN oxytocin injections reduced behavioral and corticosterone responses to immobilization whereas injections of an oxytocin receptor antagonist blocked the effects of the social buffering. Conclusions Together, our data demonstrate that PVN oxytocin mediates the social buffering effects on the stress response, and thus may be a target for treatment of stress-related disorders. PMID:24183103

Composition of Ragusano cheese during aging.

PubMed

Licitra, G; Campo, P; Manenti, M; Portelli, G; Scuderi, S; Carpino, S; Barbano, D M

2000-03-01

Ragusano cheese is a brine-salted pasta filata cheese. Composition changes during 12 mo of aging were determined. Historically, Ragusano cheese has been aged in caves at 14 to 16 degrees C with about 80 to 90% relative humidity. Cheeses (n = 132) included in our study of block-to-block variation were produced by 20 farmhouse cheese makers in the Hyblean plain region of the Province of Ragusa in Sicily. Mean initial cheese block weight was about 14 kg. The freshly formed blocks of cheese before brine salting contained about 45.35% moisture, 25.3% protein, and 25.4% fat, with a pH of 5.25. As result of the brining and aging process, a natural rind forms. After 12 mo of aging, the cheese contained about 33.6% moisture, 29.2% protein, 30.0% fat, and 4.4% salt with a pH of 5.54, but block-to-block variation was large. Both soluble nitrogen content and free fatty acid (FFA) content increased with age. The pH 4.6 acetate buffer and 12% TCA-soluble nitrogen as a percentage of total nitrogen were 16 and 10.7%, respectively, whereas the FFA content was about 643 mg/100 g of cheese at 180 d. Five blocks of cheese were selected at 180 d for a study of variation within block. Composition variation within block was large; the center had higher moisture and lower salt in moisture content than did the outside. Composition variation within blocks favored more proteolysis and softer texture in the center.

Administration of magnesium sulphate before rocuronium: effects on speed of onset and duration of neuromuscular block.

PubMed

Kussman, B; Shorten, G; Uppington, J; Comunale, M E

1997-07-01

The speeds of onset of pancuronium, atracurium and vecuronium are increased by prior administration of magnesium sulphate. A prospective, randomized, double-blind, controlled, clinical study was performed to examine the effects of prior i.v. administration of magnesium sulphate 60 mg kg-1 on the neuromuscular blocking effects of rocuronium 0.6 mg kg-1 during isoflurane anaesthesia. Neuromuscular function was measured electromyographically (Relaxograph) in 30 patients who received either magnesium sulphate 60 mg kg-1 or normal saline, 1-min before rocuronium 0.6 mg kg-1. Mean onset times were similar in the two groups (magnesium sulphate 71 (SD 20) s; normal saline 75 (23) s), but times to initial, 10% and 25% recovery from neuromuscular block were significantly longer in the magnesium sulphate group (42.1 (16.3), 49.0 (12.4) and 56.5 (13.2) min, respectively) than in the saline group (25.1 (9.1), 33.0 (11.1) and 35.6 (13.2) min, respectively) (P < 0.05 in all three cases). Administration of magnesium sulphate was not associated with adverse haemodynamic effects. Prior administration of magnesium sulphate, under the study conditions described, prolonged rocuronium-induced neuromuscular block but did not increase speed of onset.

Impact of paracervical block on postabortion pain in patients undergoing abortion under general anesthesia.

PubMed

Lazenby, Gweneth B; Fogelson, Nicholas S; Aeby, Tod

2009-12-01

Paracervical block is used as a way to decrease postoperative pain in patients having abortions under general anesthesia. To date, no studies have evaluated the efficacy of this practice. Patients were recruited from a university-based family planning clinic. Seventy-two patients seeking abortion under general anesthesia were enrolled into the single-blinded study. Thirty-nine patients were randomized to receive a paracervical block, and 33 were randomized to no local anesthesia. The patients completed a demographic survey and visual analog pain scales for pain prior to and at several time points after the procedure. Data regarding the need for additional pain medications postoperatively were recorded. Analysis of variance single factor and two-sample one-sided t test were used in data analysis. Experimental and control groups were similar in all measured demographic characteristics. They were also similar in gestational age, number of laminaria required, preoperative dilation, operative time, estimated blood loss and reported complications. Postoperative pain was not significantly affected by placement of a paracervical block prior to abortion under general anesthesia. The need for postoperative pain medication during recovery was similar between groups. This study does not support the hypothesized benefit of local anesthesia prior to surgical abortion under general anesthesia to reduce postoperative pain.

49 CFR 231.27 - Box and other house cars without roof hatches or placed in service after October 1, 1966.

Code of Federal Regulations, 2013 CFR

2013-10-01

... square. Square-fit taper: Nominally two (2) in twelve (12) inches (see Plate A). (vi) All chains shall be not less than nine-sixteenths (9/16) inch BBB coil chain. (vii) All handbrake rods shall be not less... coupler horn against the buffer block or end sill. (iii) Handbrake housing shall be securely fastened to...

49 CFR 231.1 - Box and other house cars built or placed in service before October 1, 1966.

Code of Federal Regulations, 2013 CFR

2013-10-01

... and passing through the inside face of knuckle when closed with coupler horn against the buffer block... brake-shaft step which will permit the brake chain to drop under the brake shaft shall not be used. U...-eighths of an inch square. Square-fit taper, nominally 2 in 12 inches. (See plate A.) (vi) Brake chain...

49 CFR 231.1 - Box and other house cars built or placed in service before October 1, 1966.

Code of Federal Regulations, 2010 CFR

2010-10-01

... and passing through the inside face of knuckle when closed with coupler horn against the buffer block... brake-shaft step which will permit the brake chain to drop under the brake shaft shall not be used. U...-eighths of an inch square. Square-fit taper, nominally 2 in 12 inches. (See plate A.) (vi) Brake chain...

49 CFR 231.27 - Box and other house cars without roof hatches or placed in service after October 1, 1966.

Code of Federal Regulations, 2012 CFR

2012-10-01

... square. Square-fit taper: Nominally two (2) in twelve (12) inches (see Plate A). (vi) All chains shall be not less than nine-sixteenths (9/16) inch BBB coil chain. (vii) All handbrake rods shall be not less... coupler horn against the buffer block or end sill. (iii) Handbrake housing shall be securely fastened to...

49 CFR 231.1 - Box and other house cars built or placed in service before October 1, 1966.

Code of Federal Regulations, 2011 CFR

2011-10-01

... and passing through the inside face of knuckle when closed with coupler horn against the buffer block... brake-shaft step which will permit the brake chain to drop under the brake shaft shall not be used. U...-eighths of an inch square. Square-fit taper, nominally 2 in 12 inches. (See plate A.) (vi) Brake chain...

49 CFR 231.27 - Box and other house cars without roof hatches or placed in service after October 1, 1966.

Code of Federal Regulations, 2014 CFR

2014-10-01

... square. Square-fit taper: Nominally two (2) in twelve (12) inches (see Plate A). (vi) All chains shall be not less than nine-sixteenths (9/16) inch BBB coil chain. (vii) All handbrake rods shall be not less... coupler horn against the buffer block or end sill. (iii) Handbrake housing shall be securely fastened to...

49 CFR 231.1 - Box and other house cars built or placed in service before October 1, 1966.

Code of Federal Regulations, 2012 CFR

2012-10-01

... and passing through the inside face of knuckle when closed with coupler horn against the buffer block... brake-shaft step which will permit the brake chain to drop under the brake shaft shall not be used. U...-eighths of an inch square. Square-fit taper, nominally 2 in 12 inches. (See plate A.) (vi) Brake chain...

49 CFR 231.27 - Box and other house cars without roof hatches or placed in service after October 1, 1966.

Code of Federal Regulations, 2011 CFR

2011-10-01

... square. Square-fit taper: Nominally two (2) in twelve (12) inches (see Plate A). (vi) All chains shall be not less than nine-sixteenths (9/16) inch BBB coil chain. (vii) All handbrake rods shall be not less... coupler horn against the buffer block or end sill. (iii) Handbrake housing shall be securely fastened to...

49 CFR 231.27 - Box and other house cars without roof hatches or placed in service after October 1, 1966.

Code of Federal Regulations, 2010 CFR

2010-10-01

... square. Square-fit taper: Nominally two (2) in twelve (12) inches (see Plate A). (vi) All chains shall be not less than nine-sixteenths (9/16) inch BBB coil chain. (vii) All handbrake rods shall be not less... coupler horn against the buffer block or end sill. (iii) Handbrake housing shall be securely fastened to...

49 CFR 231.1 - Box and other house cars built or placed in service before October 1, 1966.

Code of Federal Regulations, 2014 CFR

2014-10-01

... and passing through the inside face of knuckle when closed with coupler horn against the buffer block... brake-shaft step which will permit the brake chain to drop under the brake shaft shall not be used. U...-eighths of an inch square. Square-fit taper, nominally 2 in 12 inches. (See plate A.) (vi) Brake chain...

Chasing the Garlock: A study of tectonic response to vertical axis rotation

NASA Astrophysics Data System (ADS)

Guest, Bernard; Pavlis, Terry L.; Golding, Heather; Serpa, Laura

2003-06-01

Vertical-axis, clockwise block rotations in the Northeast Mojave block are well documented by numerous authors. However, the effects of these rotations on the crust to the north of the Northeast Mojave block have remained unexplored. In this paper we present a model that results from mapping and geochronology conducted in the north and central Owlshead Mountains. The model suggests that some or all of the transtension and rotation observed in the Owlshead Mountains results from tectonic response to a combination of clockwise block rotation in the Northeast Mojave block and Basin and Range extension. The Owlshead Mountains are effectively an accommodation zone that buffers differential extension between the Northeast Mojave block and the Basin and Range. In addition, our model explores the complex interactions that occur between faults and fault blocks at the junction of the Garlock, Brown Mountain, and Owl Lake faults. We hypothesize that the bending of the Garlock fault by rotation of the Northeast Mojave block resulted in a misorientation of the Garlock that forced the Owl Lake fault to break in order to accommodate slip on the western Garlock fault. Subsequent sinistral slip on the Owl Lake fault offset the Garlock, creating the now possibly inactive Mule Springs strand of the Garlock fault. Dextral slip on the Brown Mountain fault then locked the Owl Lake fault, forcing the active Leach Lake strand of the Garlock fault to break.

Changes in composition and enamel demineralization inhibition activities of gallic acid at different pH values.

PubMed

Zhang, Jingyang; Huang, Xuelian; Huang, Shengbin; Deng, Meng; Xie, Xincheng; Liu, Mingdong; Liu, Hongling; Zhou, Xuedong; Li, Jiyao; Ten Cate, Jacob Martien

2015-01-01

Gallic acid (GA) has been shown to inhibit demineralization and enhance remineralization of enamel; however, GA solution is highly acidic. This study was to investigate the stability of GA solutions at various pH and to examine the resultant effects on enamel demineralization. The stability of GA in H2O or in phosphate buffer at pH 5.5, pH 7.0 and pH 10.0 was evaluated qualitatively by ultraviolet absorption spectra and quantified by high performance liquid chromatography with diode array detection (HPLC-DAD). Then, bovine enamel blocks were subjected to a pH-cycling regime of 12 cycles. Each cycle included 5 min applications with one of the following treatments: 1 g/L NaF (positive control), 4 g/L GA in H2O or buffered at pH 5.5, pH 7.0 and pH 10.0 and buffers without GA at the same pH (negative control), followed by a 60 min application with pH 5.0 acidic buffers and a 5 min application with neutral buffers. The acidic buffers were analysed for dissolved calcium. GA was stable in pure water and acidic condition, but was unstable in neutral and alkaline conditions, in which ultraviolet spectra changed and HPLC-DAD analysis revealed that most of the GA was degraded. All the GA groups significantly inhibited demineralization (p < 0.05) and there was no significant difference of the inhibition efficacy among different GA groups (p > 0.05). GA could inhibit enamel demineralization and the inhibition effect is not influenced by pH. GA could be a useful source as an anti-cariogenic agent for broad practical application.

A social identification approach to the effects of religious disclosures in business communication.

PubMed

Carr, Caleb T

2017-01-01

This research expands on prior research into the effects of religious disclosures on interpersonal attraction by drawing from social identification theory to explain attributions stemming from religious disclosures in professionals' e-mail signature blocks. Participants (N = 268) were randomly exposed to one of three experimental conditions (a Christian, Islamic, or secular quotation in a signature block) and completed measures of social identification and perceptions of professionalism. Results indicate that, contrary to prior research, merely disclosing one's religion does not increase attributions; rather, attributions of a sender's professionalism are positively derived from the receiver's social identification with the sender's religion. Implications of these findings are discussed with regard to social identity theory, as well as for professional practice in developing signature blocks as a means of self-presentation.

An IO block array in a radiation-hardened SOI SRAM-based FPGA

NASA Astrophysics Data System (ADS)

Yan, Zhao; Lihua, Wu; Xiaowei, Han; Yan, Li; Qianli, Zhang; Liang, Chen; Guoquan, Zhang; Jianzhong, Li; Bo, Yang; Jiantou, Gao; Jian, Wang; Ming, Li; Guizhai, Liu; Feng, Zhang; Xufeng, Guo; Kai, Zhao; Chen, Stanley L.; Fang, Yu; Zhongli, Liu

2012-01-01

We present an input/output block (IOB) array used in the radiation-hardened SRAM-based field-programmable gate array (FPGA) VS1000, which is designed and fabricated with a 0.5 μm partially depleted silicon-on-insulator (SOI) logic process at the CETC 58th Institute. Corresponding with the characteristics of the FPGA, each IOB includes a local routing pool and two IO cells composed of a signal path circuit, configurable input/output buffers and an ESD protection network. A boundary-scan path circuit can be used between the programmable buffers and the input/output circuit or as a transparent circuit when the IOB is applied in different modes. Programmable IO buffers can be used at TTL/CMOS standard levels. The local routing pool enhances the flexibility and routability of the connection between the IOB array and the core logic. Radiation-hardened designs, including A-type and H-type body-tied transistors and special D-type registers, improve the anti-radiation performance. The ESD protection network, which provides a high-impulse discharge path on a pad, prevents the breakdown of the core logic caused by the immense current. These design strategies facilitate the design of FPGAs with different capacities or architectures to form a series of FPGAs. The functionality and performance of the IOB array is proved after a functional test. The radiation test indicates that the proposed VS1000 chip with an IOB array has a total dose tolerance of 100 krad(Si), a dose survivability rate of 1.5 × 1011 rad(Si)/s, and a neutron fluence immunity of 1 × 1014 n/cm2.

Immunohistochemistry for the detection of neural and inflammatory cells in equine brain tissue

PubMed Central

Liu, Junjie; Herrington, Jenna M.; Vallario, Kelsey

2016-01-01

Phenotypic characterization of cellular responses in equine infectious encephalitides has had limited description of both peripheral and resident cell populations in central nervous system (CNS) tissues due to limited species-specific reagents that react with formalin-fixed, paraffin embedded tissue (FFPE). This study identified a set of antibodies for investigating the immunopathology of infectious CNS diseases in horses. Multiple commercially available staining reagents and antibodies derived from antigens of various species for manual immunohistochemistry (IHC) were screened. Several techniques and reagents for heat-induced antigen retrieval, non-specific protein blocking, endogenous peroxidase blocking, and visualization-detection systems were tested during IHC protocol development. Boiling of slides in a low pH, citrate-based buffer solution in a double-boiler system was most consistent for epitope retrieval. Pressure-cooking, microwaving, high pH buffers, and proteinase K solutions often resulted in tissue disruption or no reactivity. Optimal blocking reagents and concentrations of each working antibody were determined. Ultimately, a set of monoclonal (mAb) and polyclonal antibodies (pAb) were identified for CD3+ (pAb A0452, Dako) T-lymphocytes, CD79αcy+ B-lymphocytes (mAb HM57, Dako), macrophages (mAb MAC387, Leica), NF-H+ neurons (mAb NAP4, EnCor Biotechnology), microglia/macrophage (pAb Iba-1, Wako), and GFAP+ astrocytes (mAb 5C10, EnCor Biotechnology). In paraffin embedded tissues, mAbs and pAbs derived from human and swine antigens were very successful at binding equine tissue targets. Individual, optimized protocols are provided for each positively reactive antibody for analyzing equine neuroinflammatory disease histopathology. PMID:26855862

Local anesthetic-induced inhibition of human neutrophil priming: the influence of structure, lipophilicity, and charge.

PubMed

Picardi, Susanne; Cartellieri, Sibylle; Groves, Danja; Hahnenkamp, Klaus; Hahnenekamp, Klaus; Gerner, Peter; Durieux, Marcel E; Stevens, Markus F; Lirk, Philipp; Hollmann, Markus W

2013-01-01

Local anesthetics (LAs) are widely known for inhibition of voltage-gated sodium channels underlying their antiarrhythmic and antinociceptive effects. However, LAs have significant immunomodulatory properties and were shown to affect human neutrophil functions independent of sodium-channel blockade. Previous studies suggest a highly selective interaction between LAs and the α-subunit of G protein-coupled receptors of the Gq/G11 family as underlying mechanism. Providing a detailed structure function analysis, this study aimed to determine the active parts within the LA molecule responsible for the effects on human neutrophil priming. Human neutrophils were incubated with structurally different LAs for 60 minutes, followed by priming and activation using either platelet-activating factor or lysophosphatidic acid and N-formyl-methionyl-L-leucyl-L-phenylalanine. Superoxide anion generation was determined, using the cytochrome c reduction assay. Differences in priming inhibition of human neutrophils between LAs were smaller than expected, although significant. Ester-linked LAs blocked priming responses more effectively than did amide LAs. Furthermore, the inhibitory potency of LAs on priming decreased with an increase of their respective octanol-buffer coefficient, and inhibition did not correlate with sodium-channel-blocking potency. Charge was not crucially required for priming inhibition, yet it played a role in effect size. Local anesthetics significantly attenuated Gαq-protein-mediated neutrophil priming. The most potent inhibition was achieved by ester compounds, inversely correlated with their octanol-buffer coefficient, and enhanced by permanent charges within the LA molecule. No correlation to their potency of blocking sodium channels was found.

A Closer Look at Racism and Heterosexism in Medical Students' Clinical Decision-Making Related to HIV Pre-Exposure Prophylaxis (PrEP): Implications for PrEP Education.

PubMed

Calabrese, Sarah K; Earnshaw, Valerie A; Krakower, Douglas S; Underhill, Kristen; Vincent, Wilson; Magnus, Manya; Hansen, Nathan B; Kershaw, Trace S; Mayer, Kenneth H; Betancourt, Joseph R; Dovidio, John F

2018-04-01

Social biases among healthcare providers could limit PrEP access. In this survey study of 115 US medical students, we examined associations between biases (racism and heterosexism) and PrEP clinical decision-making and explored prior PrEP education as a potential buffer. After viewing a vignette about a PrEP-seeking MSM patient, participants reported anticipated patient behavior (condomless sex, extra-relational sex, and adherence), intention to prescribe PrEP to the patient, biases, and background characteristics. Minimal evidence for racism affecting clinical decision-making emerged. In unadjusted analyses, heterosexism indirectly affected prescribing intention via all anticipated behaviors, tested as parallel mediators. Participants expressing greater heterosexism more strongly anticipated increased risk behavior and adherence problems, which were associated with lower prescribing intention. The indirect effect via condomless sex remained significant adjusting for background characteristics. Prior PrEP education did not buffer any indirect effects. Heterosexism may compromise PrEP provision to MSM and should be addressed in PrEP-related medical education.

Dislocation model for aseismic fault slip in the transverse ranges of Southern California

NASA Technical Reports Server (NTRS)

Cheng, A.; Jackson, D. D.; Matsuura, M.

1985-01-01

Geodetic data at a plate boundary can reveal the pattern of subsurface displacements that accompany plate motion. These displacements are modelled as the sum of rigid block motion and the elastic effects of frictional interaction between blocks. The frictional interactions are represented by uniform dislocation on each of several rectangular fault patches. The block velocities and fault parameters are then estimated from geodetic data. Bayesian inversion procedure employs prior estimates based on geological and seismological data. The method is applied to the Transverse Ranges, using prior geological and seismological data and geodetic data from the USGS trilateration networks. Geodetic data imply a displacement rate of about 20 mm/yr across the San Andreas Fault, while the geologic estimates exceed 30 mm/yr. The prior model and the final estimates both imply about 10 mm/yr crustal shortening normal to the trend of the San Andreas Fault. Aseismic fault motion is a major contributor to plate motion. The geodetic data can help to identify faults that are suffering rapid stress accumulation; in the Transverse Ranges those faults are the San Andreas and the Santa Susana.

Adaptive local thresholding for robust nucleus segmentation utilizing shape priors

NASA Astrophysics Data System (ADS)

Wang, Xiuzhong; Srinivas, Chukka

2016-03-01

This paper describes a novel local thresholding method for foreground detection. First, a Canny edge detection method is used for initial edge detection. Then, tensor voting is applied on the initial edge pixels, using a nonsymmetric tensor field tailored to encode prior information about nucleus size, shape, and intensity spatial distribution. Tensor analysis is then performed to generate the saliency image and, based on that, the refined edge. Next, the image domain is divided into blocks. In each block, at least one foreground and one background pixel are sampled for each refined edge pixel. The saliency weighted foreground histogram and background histogram are then created. These two histograms are used to calculate a threshold by minimizing the background and foreground pixel classification error. The block-wise thresholds are then used to generate the threshold for each pixel via interpolation. Finally, the foreground is obtained by comparing the original image with the threshold image. The effective use of prior information, combined with robust techniques, results in far more reliable foreground detection, which leads to robust nucleus segmentation.

Rapid Bedside Inactivation of Ebola Virus for Safe Nucleic Acid Tests.

PubMed

Rosenstierne, Maiken Worsøe; Karlberg, Helen; Bragstad, Karoline; Lindegren, Gunnel; Stoltz, Malin Lundahl; Salata, Cristiano; Kran, Anne-Marte Bakken; Dudman, Susanne Gjeruldsen; Mirazimi, Ali; Fomsgaard, Anders

2016-10-01

Rapid bedside inactivation of Ebola virus would be a solution for the safety of medical and technical staff, risk containment, sample transport, and high-throughput or rapid diagnostic testing during an outbreak. We show that the commercially available Magna Pure lysis/binding buffer used for nucleic acid extraction inactivates Ebola virus. A rapid bedside inactivation method for nucleic acid tests is obtained by simply adding Magna Pure lysis/binding buffer directly into vacuum blood collection EDTA tubes using a thin needle and syringe prior to sampling. The ready-to-use inactivation vacuum tubes are stable for more than 4 months, and Ebola virus RNA is preserved in the Magna Pure lysis/binding buffer for at least 5 weeks independent of the storage temperature. We also show that Ebola virus RNA can be manually extracted from Magna Pure lysis/binding buffer-inactivated samples using the QIAamp viral RNA minikit. We present an easy and convenient method for bedside inactivation using available blood collection vacuum tubes and reagents. We propose to use this simple method for fast, safe, and easy bedside inactivation of Ebola virus for safe transport and routine nucleic acid detection. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Optimization of the cydex blue assay: A one-step colorimetric protein assay using cyclodextrins and compatible with detergents and reducers

PubMed Central

2018-01-01

Sodium dodecyl sulfate electrophoresis (SDS) is a protein separation technique widely used, for example, prior to immunoblotting. Samples are usually prepared in a buffer containing both high concentrations of reducers and high concentrations of SDS. This conjunction renders the samples incompatible with common protein assays. By chelating the SDS, cyclodextrins make the use of simple, dye-based colorimetric assays possible. In this paper, we describe the optimization of the assay, focussing on the cyclodextrin/SDS ratio and the use of commercial assay reagents. The adaptation of the assay to a microplate format and using other detergent-containing conventional extraction buffers is also described. PMID:29641569

Effect of buffer on the immune response to trivalent oral poliovirus vaccine in Bangladesh: a community based randomized controlled trial.

PubMed

Chandir, Subhash; Ahamed, Kabir U; Baqui, Abdullah H; Sutter, Roland W; Okayasu, Hiromasa; Pallansch, Mark A; Oberste, Mark S; Moulton, Lawrence H; Halsey, Neal A

2014-11-01

Polio eradication efforts have been hampered by low responses to trivalent oral poliovirus vaccine (tOPV) in some developing countries. Since stomach acidity may neutralize vaccine viruses, we assessed whether administration of a buffer solution could improve the immunogenicity of tOPV. Healthy infants 4-6 weeks old in Sylhet, Bangladesh, were randomized to receive tOPV with or without a sodium bicarbonate and sodium citrate buffer at age 6, 10, and 14 weeks. Levels of serum neutralizing antibodies for poliovirus types 1, 2, and 3 were measured before and after vaccination, at 6 and 18 weeks of age, respectively. Serologic response rates following 3 doses of tOPV for buffer recipients and control infants were 95% and 88% (P=.065), respectively, for type 1 poliovirus; 95% and 97% (P=.543), respectively, for type 2 poliovirus; and 90% and 89% (P=.79), respectively, for type 3 poliovirus. Administration of a buffer solution prior to vaccination was not associated with statistically significant increases in the immune response to tOPV; however, a marginal 7% increase (P=.065) in serologic response to poliovirus type 1 was observed. NCT01579825. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Evaluation of AlGaN/GaN high electron mobility transistors grown on ZrTi buffer layers with sapphire substrates

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

Ren, Fan; Pearton, Stephen J.; Ahn, Shihyun

Here, AlGaN/GaN high electron mobility transistors (HEMTs) have been grown on sapphire substrates, using ZrTi buffer layers to provide in-plane lattice-matching to hexagonal GaN. X-ray diffraction (XRD) as well as cross-section transmission electron microscopy (TEM) were used to assess the quality of the HEMT structure. The XRD 2θ scans showed full-width-at-half-maximum values of 0.16°, 0.07°, and 0.08° for ZrTi alloy, GaN buffer layer, and the entire HEMT structure, respectively. TEM studies of the GaN buffer layer and the AlN/ZrTi/AlN stack showed the importance of growing thin AlN buffer layers on the ZrTi layer prior to growth of the GaN buffermore » layer. The density of threading dislocations in the GaN channel layer of the HEMT structure was estimated to be in the 10 8 cm –2 range. The HEMT device exhibited a saturation drain current density of 820 mA/mm, and the channel of the fabricated HEMTs could be well modulated. A cutoff frequency (f T) of 8.9 GHz and a maximum frequency of oscillation (f max) of 17.3 GHz were achieved for HEMTs with gate dimensions of 1 × 200 μm.« less

Evaluation of AlGaN/GaN high electron mobility transistors grown on ZrTi buffer layers with sapphire substrates

DOE PAGES

Ren, Fan; Pearton, Stephen J.; Ahn, Shihyun; ...

2016-09-21

Here, AlGaN/GaN high electron mobility transistors (HEMTs) have been grown on sapphire substrates, using ZrTi buffer layers to provide in-plane lattice-matching to hexagonal GaN. X-ray diffraction (XRD) as well as cross-section transmission electron microscopy (TEM) were used to assess the quality of the HEMT structure. The XRD 2θ scans showed full-width-at-half-maximum values of 0.16°, 0.07°, and 0.08° for ZrTi alloy, GaN buffer layer, and the entire HEMT structure, respectively. TEM studies of the GaN buffer layer and the AlN/ZrTi/AlN stack showed the importance of growing thin AlN buffer layers on the ZrTi layer prior to growth of the GaN buffermore » layer. The density of threading dislocations in the GaN channel layer of the HEMT structure was estimated to be in the 10 8 cm –2 range. The HEMT device exhibited a saturation drain current density of 820 mA/mm, and the channel of the fabricated HEMTs could be well modulated. A cutoff frequency (f T) of 8.9 GHz and a maximum frequency of oscillation (f max) of 17.3 GHz were achieved for HEMTs with gate dimensions of 1 × 200 μm.« less

Reconsidering the effects of poverty and social support on health: a 5-year longitudinal test of the stress-buffering hypothesis.

PubMed

Moskowitz, David; Vittinghoff, Eric; Schmidt, Laura

2013-02-01

Prior research in the general population has found that social support can buffer the adverse effects of stressors on health. However, both stressors and social support may be qualitatively different for those living in urban poverty. We examined the effects of social support and poverty-specific stressors on self-rated health. We used data from the Welfare Client Longitudinal Survey (WCLS), a 5-year longitudinal study of 718 public aid recipients. We measured received social support and "net social support," defined as the difference between support received and that given to others. We used restricted cubic splines to model the stress-buffering effects of social support on self-rated health as a function of stressful life events and neighborhood disorder. Increased exposure to stressors was associated with poorer self-rated health. Evidence of stress buffering was confined to those with the heaviest exposure to stressors, and its effects decreased across increasing levels of social support. Analyses using net social support had generally more modest effects than those using received social support. Social support does not buffer the effects of stressors on health uniformly for individuals living in conditions of urban poverty. Researchers and policymakers should be cautious in overestimating the beneficial effects that social support may have on health for marginalized populations.

Method of making high breakdown voltage semiconductor device

DOEpatents

Arthur, Stephen D.; Temple, Victor A. K.

1990-01-01

A semiconductor device having at least one P-N junction and a multiple-zone junction termination extension (JTE) region which uniformly merges with the reverse blocking junction is disclosed. The blocking junction is graded into multiple zones of lower concentration dopant adjacent termination to facilitate merging of the JTE to the blocking junction and placing of the JTE at or near the high field point of the blocking junction. Preferably, the JTE region substantially overlaps the graded blocking junction region. A novel device fabrication method is also provided which eliminates the prior art step of separately diffusing the JTE region.

The effect of extracellular weak acids and bases on the intracellular buffering power of snail neurones.

PubMed Central

Szatkowski, M S

1989-01-01

1. Intracellular pH (pHi) was measured in snail neurones using pH-sensitive glass microelectrodes. The influence of externally applied weak acids and bases on the total intracellular buffering power (beta T) was investigated by monitoring the pHi changes caused by the intracellular ionophoretic injection of HCl. 2. In the absence of weak acids or bases a reduction in the extracellular HEPES concentration had no effect on pHi or on beta T. It did, however, reduce slightly the rate of pHi recovery following HCl injection. 3. The presence of CO2 greatly increased beta T. However, as predicted for an open buffer system, the contributions to intracellular buffering by CO2 (beta CO2) decreased as pHi decreased. 4. When added to the superfusate, procaine, 4-aminopyridine, trimethylamine and NH4Cl (1-10 mM) all increased steady-state pHi. Procaine was fastest at increasing pHi and 4-aminopyridine the slowest. All four of these weak bases increased beta T. 5. The intracellular buffering action by these weak bases varied. HCl injection in the presence of procaine usually resulted in steady-state pHi changes with no pHi transients. In the presence of the other three weak bases HCl injections resulted in intracellular acidifications which were followed by pHi recovery-like transients. However, these were not blocked by SITS (4-acetamido-4'-isothiocyanatostilbene-2,2'-disulphonic acid) or by CaCl2 and I thus conclude that these transients were as a result of slow or incomplete intracellular buffering by the weak bases. 6. In many cells there was a good correlation between the measured contributions to intracellular buffering by the weak bases (beta base) and those predicted assuming a simple two-compartment open system. In all cases, as predicted, beta base increased as pHi decreased. 7. I found a clear relationship between the concentration of external buffer (HEPES) and the rate at which weak bases, applied to the superfusate, were able to increase pHi. The greater the extracellular buffer concentration the greater was the speed of intracellular alkalinization. 8. Lowering the extracellular buffer concentration reduced the efficiency of intracellular buffering by weak bases in response to an intracellular acid load. HCl injection in the presence of weak base caused a larger initial intracellular acidification if the extracellular HEPES concentration was reduced. 9. In conclusion, both weak acids and weak bases can make very large, pHi-dependent contributions to intracellular buffering by way of open buffer systems.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:2555474

Asynchronous Communication of TLNS3DMB Boundary Exchange

NASA Technical Reports Server (NTRS)

Hammond, Dana P.

1997-01-01

This paper describes the recognition of implicit serialization due to coarse-grain, synchronous communication and demonstrates the conversion to asynchronous communication for the exchange of boundary condition information in the Thin-Layer Navier Stokes 3-Dimensional Multi Block (TLNS3DMB) code. The implementation details of using asynchronous communication is provided including buffer allocation, message identification, and barrier control. The IBM SP2 was used for the tests presented.

A VLSI-Based High-Performance Raster Image System.

DTIC Science & Technology

1986-05-08

and data in broadcast form to the array of memory -hips in the frame buffer, shown in the bottom block. This is simply a physical structure to hold up...Principal Investigator: John Poulton Collaboration on algorithm development: Prof. Jack Goldfeather (Dept. of Mathematics, Carleton Collge ...1983) Cheng-Hong Hsieh (MS, Computer Science, May, 1985) Jeff P. Hultquist Susan Spach Undergraduate ResearLh Assistant: Sonya Holder (BS, Physics , May

Soil Parameter Mapping and Ad Hoc Power Analysis to Increase Blocking Efficiency Prior to Establishing a Long-Term Field Experiment.

PubMed

Collins, Doug; Benedict, Chris; Bary, Andy; Cogger, Craig

2015-01-01

The spatial heterogeneity of soil and weed populations poses a challenge to researchers. Unlike aboveground variability, below-ground variability is more difficult to discern without a strategic soil sampling pattern. While blocking is commonly used to control environmental variation, this strategy is rarely informed by data about current soil conditions. Fifty georeferenced sites were located in a 0.65 ha area prior to establishing a long-term field experiment. Soil organic matter (OM) and weed seed bank populations were analyzed at each site and the spatial structure was modeled with semivariograms and interpolated with kriging to map the surface. These maps were used to formulate three strategic blocking patterns and the efficiency of each pattern was compared to a completely randomized design and a west to east model not informed by soil variability. Compared to OM, weeds were more variable across the landscape and had a shorter range of autocorrelation, and models to increase blocking efficiency resulted in less increase in power. Weeds and OM were not correlated, so no model examined improved power equally for both parameters. Compared to the west to east blocking pattern, the final blocking pattern chosen resulted in a 7-fold increase in power for OM and a 36% increase in power for weeds.

A Low Power and High Throughput Self Synchronous FPGA Using 65nm CMOS with Throughput Optimization by Pipeline Alignment

NASA Astrophysics Data System (ADS)

Stefan Devlin, Benjamin; Nakura, Toru; Ikeda, Makoto; Asada, Kunihiro

We detail a self synchronous field programmable gate array (SSFPGA) with dual-pipeline (DP) architecture to conceal pre-charge time for dynamic logic, and its throughput optimization by using pipeline alignment implemented on benchmark circuits. A self synchronous LUT (SSLUT) consists of a three input tree-type structure with 8bits of SRAM for programming. A self synchronous switch box (SSSB) consists of both pass transistors and buffers to route signals, with 12bits of SRAM. One common block with one SSLUT and one SSSB occupies 2.2Mλ2 area with 35bits of SRAM, and the prototype SSFPGA with 34 × 30 (1020) blocks is designed and fabricated using 65nm CMOS. Measured results show at 1.2V 430MHz and 647MHz operation for a 3bit ripple carry adder, without and with throughput optimization, respectively. We find that using the proposed pipeline alignment techniques we can perform at maximum throughput of 647MHz in various benchmarks on the SSFPGA. We demonstrate up to 56.1 times throughput improvement with our pipeline alignment techniques. The pipeline alignment is carried out within the number of logic elements in the array and pipeline buffers in the switching matrix.

Polyvalent immunoglobulin binding is an obstacle to accurate measurement of specific antibodies with ELISA despite inclusion of blocking agents.

PubMed

Loeffler, David A; Klaver, Andrea C

2017-11-01

Specific antibody concentrations are frequently measured in serum (and plasma and intravenous immunoglobulin) samples by enzyme-linked immunosorbent assay (ELISA). The standard negative control involves incubation of buffer alone on antigen-coated wells. The immunoreactivity that develops in antigen-coated wells in which diluted serum has been incubated is assumed to represent specific antibody binding. This approach can result in marked overestimation of specific antibody levels, because serum contains specific polyvalent antibodies which bind, primarily with low affinity, to multiple antigens (including those on ELISA plates) despite the use of blocking agents. Non-denaturing purification of serum IgG, followed by assessment of the antigen binding or antigen-binding affinity of this purified IgG, can reduce but not eliminate the problem of polyvalent antibody binding in indirect ELISAs. Alternatively, polyvalent antibody binding can be estimated by incubating a diluted serum sample on wells coated with an irrelevant protein (such as bovine serum albumin or a scrambled peptide sequence) or buffer alone, then subtracting this reactivity from the sample's binding to wells coated with the antigen of interest. Polyvalent binding of immunoglobulins must be accounted for in order to obtain accurate ELISA measurements of serum, plasma, or intravenous immunoglobulin antibodies. Copyright © 2017 Elsevier B.V. All rights reserved.

Degradation and protein release properties of microspheres prepared from biodegradable poly(lactide-co-glycolide) and ABA triblock copolymers: influence of buffer media on polymer erosion and bovine serum albumin release.

PubMed

Bittner, B; Witt, C; Mäder, K; Kissel, T

1999-08-05

The aim of the present study was to investigate the influence of the chemical insertion of poly(ethylene oxide), PEO, into a poly(lactide-co-glycolide), PLG, backbone on the mechanisms of in vitro degradation and erosion of the polymer. For this purpose microspheres prepared by a modified W/O/W double emulsion technique using ABA triblock copolymers, consisting of PLG A-blocks attached to central PEO B-blocks were compared with microspheres prepared from PLG. Due to their molecular architecture the ABA triblock copolymers differed in their erosion and degradation behavior from PLG. Degradation occurred faster in the ABA polymers by cleavage of ester bonds inside the polymer backbone. Even erosion was shown to start immediately after incubation in different buffer media. By varying pH and ionic strength of the buffer it was found that both mass loss and molecular weight decay were accelerated in alkaline and acidic pH in the case of the ABA triblock copolymers. Although the pH of the medium had a moderate influence on the degradation of PLG, the molecular weight decay was not accompanied by a mass loss during the observation time. In a second set of experiments we prepared bovine serum albumin, BSA, loaded microspheres from both polymers. The release of BSA from ABA microspheres under in vitro conditions parallels the faster swelling and erosion rates. This could be confirmed by electron paramagnetic resonance, EPR, measurements with spin labeled albumin where an influx of buffer medium into the ABA microspheres was already observed within a few minutes. In contrast, PLG microspheres revealed a burst release without any erosion. The current study shows that the environmental conditions affected the degradation and erosion of the pure polymer microspheres in the same way as the release of the model protein. This leads to the conclusion that the more favorable degradation profile of the ABA triblock copolymers was responsible for the improvement of the release profile.

Polycation-sodium lauryl ether sulfate-type surfactant complexes: influence of ethylene oxide length.

PubMed

Vleugels, Leo F W; Pollet, Jennifer; Tuinier, Remco

2015-05-21

Polyelectrolyte-surfactant complexes (PESC) are a class of materials which form spontaneously by self-assembly driven by electrostatic and hydrophobic interactions. PESC containing sodium lauryl ether sulfates (SLES) have found wide application in hair care products like shampoo. Typically, SLES with only one or two ethylene oxide (EO) groups are used for this application. We have studied the influence of the size of the EO block (ranging from 0 to 30 EO groups) on complexation with two model polycations: linear polyDADMAC and branched PEI. PESC size and electrostatic properties were determined during stepwise titration of buffered polycation solutions. The critical aggregation concentration (CAC) of PESC was determined by surface tension measurements and fluorescence spectroscopy. For polyDADMAC, there is no influence of the size of the EO block on the complexation behavior; the stiff polycation governs the structure formation. For PEI, it was seen that the EO block size does affect the structure of the complexes. The CAC value of the investigated complexes turns out to be rather independent of the EO block size; however, the CMC/CAC ratio decreases with increasing size of the EO block. This latter observation explains why the Lochhead-Goddard effect is most effective for small EO blocks.

The StreamCat Dataset: Accumulated Attributes for NHDPlusV2 Catchments (Version 2.1) for the Conterminous United States: 2010 US Census Housing Unit and Population Density

EPA Pesticide Factsheets

This dataset represents the population and housing unit density within individual, local NHDPlusV2 catchments and upstream, contributing watersheds based on 2010 US Census data. Densities are calculated for every block group and watershed averages are calculated for every local NHDPlusV2 catchment(see Data Sources for links to NHDPlusV2 data and Census Data). This data set is derived from The TIGER/Line Files and related database (.dbf) files for the conterminous USA. It was downloaded as Block Group-Level Census 2010 SF1 Data in File Geodatabase Format (ArcGIS version 10.0). The landscape raster (LR) was produced based on the data compiled from the questions asked of all people and about every housing unit. The (block-group population / block group area) and (block-group housing units / block group area) were summarized by local catchment and by watershed to produce local catchment-level and watershed-level metrics as a continuous data type (see Data Structure and Attribute Information for a description). Using a riparian buffer(see Process Steps), statistics were generated for areas within each catchment that are within 100 meters of the stream reach in an attempt to evaluate for the riparian zone.

A dynamic system for the simulation of fasting luminal pH-gradients using hydrogen carbonate buffers for dissolution testing of ionisable compounds.

PubMed

Garbacz, Grzegorz; Kołodziej, Bartosz; Koziolek, Mirko; Weitschies, Werner; Klein, Sandra

2014-01-23

The hydrogen carbonate buffer is considered as the most biorelevant buffer system for the simulation of intestinal conditions and covers the physiological pH range of the luminal fluids from pH 5.5 to about pH 8.4. The pH value of a hydrogen carbonate buffer is the result of a complex and dynamic interplay of the concentration of hydrogen carbonate ions, carbonic acid, the concentration of dissolved and solvated carbon dioxide and its partial pressure above the solution. The complex equilibrium between the different ions results in a thermodynamic instability of hydrogen carbonate solutions. In order to use hydrogen carbonate buffers with pH gradients in the physiological range and with the dynamics observed in vivo without changing the ionic strength of the solution, we developed a device (pHysio-grad®) that provides both acidification of the dissolution medium by microcomputer controlled carbon dioxide influx and alkalisation by degassing. This enables a continuous pH control and adjustment during dissolution of ionisable compounds. The results of the pH adjustment indicate that the system can compensate even rapid pH changes after addition of a basic or acidic moiety in amounts corresponding up to 90% of the overall buffer capacity. The results of the dissolution tests performed for a model formulation containing ionizable compounds (Nexium 20mg mups) indicate that both the simulated fasting intraluminal pH-profiles and the buffer species can significantly affect the dissolution process by changing the lag time prior to initial drug release and the release rate of the model compound. A prediction of the in vivo release behaviour of this formulation is thus most likely strongly related to the test conditions such as pH and buffer species. Copyright © 2013 Elsevier B.V. All rights reserved.

Between two beds: inappropriately delayed discharges from hospitals.

PubMed

Holmås, Tor Helge; Islam, Mohammad Kamrul; Kjerstad, Egil

2013-12-01

Acknowledging the necessity of a division of labour between hospitals and social care services regarding treatment and care of patients with chronic and complex conditions, is to acknowledge the potential conflict of interests between health care providers. A potentially important conflict is that hospitals prefer comparatively short length of stay (LOS) at hospital, while social care services prefer longer LOS all else equal. Furthermore, inappropriately delayed discharges from hospital, i.e. bed blocking, is costly for society. Our aim is to discuss which factors that may influence bed blocking and to quantify bed blocking costs using individual Norwegian patient data, merged with social care and hospital data. The data allow us to divide hospital LOS into length of appropriate stay (LAS) and length of delay (LOD), the bed blocking period. We find that additional resources allocated to social care services contribute to shorten LOD indicating that social care services may exploit hospital resources as a buffer for insufficient capacity. LAS increases as medical complexity increases indicating hospitals incentives to reduce LOS are softened by considerations related to patients’ medical needs. Bed blocking costs constitute a relatively large share of the total costs of inpatient care.

Capture and playback synchronization in video conferencing

NASA Astrophysics Data System (ADS)

Shae, Zon-Yin; Chang, Pao-Chi; Chen, Mon-Song

1995-03-01

Packet-switching based video conferencing has emerged as one of the most important multimedia applications. Lip synchronization can be disrupted in the packet network as the result of the network properties: packet delay jitters at the capture end, network delay jitters, packet loss, packet arrived out of sequence, local clock mismatch, and video playback overlay with the graphic system. The synchronization problem become more demanding as the real time and multiparty requirement of the video conferencing application. Some of the above mentioned problem can be solved in the more advanced network architecture as ATM having promised. This paper will present some of the solutions to the problems that can be useful at the end station terminals in the massively deployed packet switching network today. The playback scheme in the end station will consist of two units: compression domain buffer management unit and the pixel domain buffer management unit. The pixel domain buffer management unit is responsible for removing the annoying frame shearing effect in the display. The compression domain buffer management unit is responsible for parsing the incoming packets for identifying the complete data blocks in the compressed data stream which can be decoded independently. The compression domain buffer management unit is also responsible for concealing the effects of clock mismatch, lip synchronization, and packet loss, out of sequence, and network jitters. This scheme can also be applied to the multiparty teleconferencing environment. Some of the schemes presented in this paper have been implemented in the Multiparty Multimedia Teleconferencing (MMT) system prototype at the IBM watson research center.

Hypothalamic oxytocin mediates social buffering of the stress response.

PubMed

Smith, Adam S; Wang, Zuoxin

2014-08-15

While stressful life events can enhance the risk of mental disorders, positive social interactions can propagate good mental health and normal behavioral routines. Still, the neural systems that promote these benefits are undetermined. Oxytocin is a hormone involved in social behavior and stress; thus, we focus on the impact that social buffering has on the stress response and the governing effects of oxytocin. Female prairie voles (Microtus ochrogaster) were exposed to 1 hour immobilization stress and then recovered alone or with their male partner to characterize the effect of social contact on the behavioral, physiological, and neuroendocrine stress response. In addition, we treated immobilized female voles recovering alone with oxytocin or vehicle and female voles recovering with their male partner with a selective oxytocin receptor antagonist or vehicle. Group sizes varied from 6 to 8 voles (N = 98 total). We found that 1 hour immobilization increased anxiety-like behaviors and circulating levels of corticosterone, a stress hormone, in female prairie voles recovering alone but not the female prairie voles recovering with their male partner. This social buffering by the male partner on biobehavioral responses to stress was accompanied by increased oxytocin release in the paraventricular nucleus of the hypothalamus. Intra-paraventricular nucleus oxytocin injections reduced behavioral and corticosterone responses to immobilization, whereas injections of an oxytocin receptor antagonist blocked the effects of the social buffering. Together, our data demonstrate that paraventricular nucleus oxytocin mediates the social buffering effects on the stress response and thus may be a target for treatment of stress-related disorders. Published by Society of Biological Psychiatry on behalf of Society of Biological Psychiatry.

Gaussian curvature analysis allows for automatic block placement in multi-block hexahedral meshing.

PubMed

Ramme, Austin J; Shivanna, Kiran H; Magnotta, Vincent A; Grosland, Nicole M

2011-10-01

Musculoskeletal finite element analysis (FEA) has been essential to research in orthopaedic biomechanics. The generation of a volumetric mesh is often the most challenging step in a FEA. Hexahedral meshing tools that are based on a multi-block approach rely on the manual placement of building blocks for their mesh generation scheme. We hypothesise that Gaussian curvature analysis could be used to automatically develop a building block structure for multi-block hexahedral mesh generation. The Automated Building Block Algorithm incorporates principles from differential geometry, combinatorics, statistical analysis and computer science to automatically generate a building block structure to represent a given surface without prior information. We have applied this algorithm to 29 bones of varying geometries and successfully generated a usable mesh in all cases. This work represents a significant advancement in automating the definition of building blocks.

EFFECTS OF SPATIAL EXTENT ON LANDSCAPE STRUCTURE AND SEDIMENT METAL CONCENTRATION RELATIONSHIPS IN SMALL ESTUARINE SYSTEMS OF THE US MID-ATLANTIC COAST

EPA Science Inventory

Prior studies exploring the quantitative relationship between landscape structure metrics and the ecological condition of receiving waters have used a variety of sampling units (e.g. a watershed, or a buffer around a sampling station) at a variety of spatial scales to generate la...

The Role of Frontal Cortical and Medial-Temporal Lobe Brain Areas in Learning a Bayesian Prior Belief on Reversals

PubMed Central

Jang, Anthony I.; Costa, Vincent D.; Rudebeck, Peter H.; Chudasama, Yogita; Murray, Elisabeth A.

2015-01-01

Reversal learning has been extensively studied across species as a task that indexes the ability to flexibly make and reverse deterministic stimulus–reward associations. Although various brain lesions have been found to affect performance on this task, the behavioral processes affected by these lesions have not yet been determined. This task includes at least two kinds of learning. First, subjects have to learn and reverse stimulus–reward associations in each block of trials. Second, subjects become more proficient at reversing choice preferences as they experience more reversals. We have developed a Bayesian approach to separately characterize these two learning processes. Reversal of choice behavior within each block is driven by a combination of evidence that a reversal has occurred, and a prior belief in reversals that evolves with experience across blocks. We applied the approach to behavior obtained from 89 macaques, comprising 12 lesion groups and a control group. We found that animals from all of the groups reversed more quickly as they experienced more reversals, and correspondingly they updated their prior beliefs about reversals at the same rate. However, the initial values of the priors that the various groups of animals brought to the task differed significantly, and it was these initial priors that led to the differences in behavior. Thus, by taking a Bayesian approach we find that variability in reversal-learning performance attributable to different neural systems is primarily driven by different prior beliefs about reversals that each group brings to the task. SIGNIFICANCE STATEMENT The ability to use prior knowledge to adapt choice behavior is critical for flexible decision making. Reversal learning is often studied as a form of flexible decision making. However, prior studies have not identified which brain regions are important for the formation and use of prior beliefs to guide choice behavior. Here we develop a Bayesian approach that formally characterizes learning set as a concept, and we show that, in macaque monkeys, the amygdala and medial prefrontal cortex have a role in establishing an initial belief about the stability of the reward environment. PMID:26290251

A versatile digitally-graded buffer structure for metamorphic device applications

NASA Astrophysics Data System (ADS)

Ma, Yingjie; Zhang, Yonggang; Chen, Xingyou; Gu, Yi; Shi, Yanhui; Ji, Wanyan; Du, Ben

2018-04-01

Exploring more effective buffer schemes for mitigating dislocation deficiencies is the key technology towards higher performance metamorphic devices. Here we demonstrate a versatile metamorphic grading structure consisting of 38-period alternated multilayers of In0.52Al0.48As and In0.82Al0.18As on InP substrate, thicknesses of which in each period were gradually varied in opposite directions from 48.7 and 1.3 nm to 1.3 and 48.7 nm, respectively, akin to a digital alloy. Both preferentially dislocation nucleation and blocking of threading dislocation transmission are observed near the In0.82Al0.18As/In0.52Al0.48As interfaces, which help relax the strain and lower the residual defect density. A 2.6 μm In0.83Ga0.17As pin photodetector is fabricated on this pseudo-substrate, attaining a low dark current density of 2.9  ×  10‑6 A cm‑2 and a high detectivity of 1.8  ×  1010 cmHz1/2W‑1 at room temperature, comparable with the states of the art that on linearly-graded buffer layers. These results indicate such digitally-graded buffer structures are promising for enhancing performances of metamorphic devices, and can be easily generalized to other lattice-mismatched material systems.

Design of a Multicast Optical Packet Switch Based on Fiber Bragg Grating Technology for Future Networks

NASA Astrophysics Data System (ADS)

Cheng, Yuh-Jiuh; Yeh, Tzuoh-Chyau; Cheng, Shyr-Yuan

2011-09-01

In this paper, a non-blocking multicast optical packet switch based on fiber Bragg grating technology with optical output buffers is proposed. Only the header of optical packets is converted to electronic signals to control the fiber Bragg grating array of input ports and the packet payloads should be transparently destined to their output ports so that the proposed switch can reduce electronic interfaces as well as the bit rate. The modulation and the format of packet payloads may be non-standard where packet payloads could also include different wavelengths for increasing the volume of traffic. The advantage is obvious: the proposed switch could transport various types of traffic. An easily implemented architecture which can provide multicast services is also presented. An optical output buffer is designed to queue the packets if more than one incoming packet should reach to the same destination output port or including any waiting packets in optical output buffer that will be sent to the output port at a time slot. For preserving service-packet sequencing and fairness of routing sequence, a priority scheme and a round-robin algorithm are adopted at the optical output buffer. The fiber Bragg grating arrays for both input ports and output ports are designed for routing incoming packets using optical code division multiple access technology.

Electrotransfection of Polyamine Folded DNA Origami Structures.

PubMed

Chopra, Aradhana; Krishnan, Swati; Simmel, Friedrich C

2016-10-12

DNA origami structures are artificial molecular nanostructures in which DNA double helices are forced into a closely packed configuration by a multitude of DNA strand crossovers. We show that three different types of origami structures (a flat sheet, a hollow tube, and a compact origami block) can be formed in magnesium-free buffer solutions containing low (<1 mM) concentrations of the condensing agent spermidine. Much like in DNA condensation, the amount of spermidine required for origami folding is proportional to the DNA concentration. At excessive amounts, the structures aggregate and precipitate. In contrast to origami structures formed in conventional buffers, the resulting structures are stable in the presence of high electric field pulses, such as those commonly used for electrotransfection experiments. We demonstrate that spermidine-stabilized structures are stable in cell lysate and can be delivered into mammalian cells via electroporation.

Prior-Based Quantization Bin Matching for Cloud Storage of JPEG Images.

PubMed

Liu, Xianming; Cheung, Gene; Lin, Chia-Wen; Zhao, Debin; Gao, Wen

2018-07-01

Millions of user-generated images are uploaded to social media sites like Facebook daily, which translate to a large storage cost. However, there exists an asymmetry in upload and download data: only a fraction of the uploaded images are subsequently retrieved for viewing. In this paper, we propose a cloud storage system that reduces the storage cost of all uploaded JPEG photos, at the expense of a controlled increase in computation mainly during download of requested image subset. Specifically, the system first selectively re-encodes code blocks of uploaded JPEG images using coarser quantization parameters for smaller storage sizes. Then during download, the system exploits known signal priors-sparsity prior and graph-signal smoothness prior-for reverse mapping to recover original fine quantization bin indices, with either deterministic guarantee (lossless mode) or statistical guarantee (near-lossless mode). For fast reverse mapping, we use small dictionaries and sparse graphs that are tailored for specific clusters of similar blocks, which are classified via tree-structured vector quantizer. During image upload, cluster indices identifying the appropriate dictionaries and graphs for the re-quantized blocks are encoded as side information using a differential distributed source coding scheme to facilitate reverse mapping during image download. Experimental results show that our system can reap significant storage savings (up to 12.05%) at roughly the same image PSNR (within 0.18 dB).

Investigating The Anti-apoptotic Effects of Shigella Flexneri Infection In Epithelial Cells

DTIC Science & Technology

2009-08-13

also been found in breast milk of convalescent mothers and most likely contribute to the reduction of disease severity in breast-fed infants (45...samples. Proteins were transferred to a nitrocellulose membrane and blocked with 5% dry milk in Tris-buffered saline (TBS). Caspases were detected by...dry milk overnight at 4°C. After washing, donkey anti- rabbit immunoglobulin G antibody conjugated to horseradish peroxidase (Amersham Biosciences

Mechanisms of Chemoresistance in Breast Cancer Cells

DTIC Science & Technology

2008-02-01

which blocks ganglioside biosynthesis at the juncture of ceramide synthase, or Vibrio cholerae neuraminidase, which cleaves cell surface gangliosides...MCF-7-AdrR and MCF-7-AdrR/GCS antisense cells were rinsed, harvested in PBS, and lysed in a PBS buffer containing 10% glycerol, 1% Triton X-100, 1.0...analysis of gangliosides. Cells harvested in PBS were homogenized in 6 mL chloroform/methanol (1:1, v/v); the mixture remained overnight at room

The effect of the processing and formulation parameters on the size of nanoparticles based on block copolymers of poly(ethylene glycol) and poly(N-isopropylacrylamide) with and without hydrolytically sensitive groups.

PubMed

Neradovic, D; Soga, O; Van Nostrum, C F; Hennink, W E

2004-05-01

Block copolymers of poly(ethylene glycol) (PEG) as a hydrophilic block and N-isopropylacrylamide (PNIPAAm) or poly (NIPAAm-co-N-(2-hydroxypropyl) methacrylamide-dilactate) (poly(NIPAAm-co-HPMAm-dilactate)) as a thermosensitive block, are able to self-assemble in water into nanoparticles above the cloud point (CP) of the thermosensitive block. The influence of processing and the formulation parameters on the size of the nanoparticles was studied using dynamic light scattering. PNIPAAm-b-PEG 2000 polymers were not suitable for the formation of small and stable particles. Block copolymers with PEG 5000 and 10000 formed relatively small and stable particles in aqueous solutions at temperatures above the CP of the thermosensitive block. Their size decreased with increasing molecular weight of the thermosensitive block, decreasing polymer concentration and using water instead of phosphate buffered saline as solvent. Extrusion and ultrasonication were inefficient methods to size down the polymeric nanoparticles. The heating rate of the polymer solutions was a dominant factor for the size of the nanoparticles. When an aqueous polymer solution was slowly heated through the CP, rather large particles (> or = 200 nm) were formed. Regardless the polymer composition, small nanoparticles (50-70 nm) with a narrow size distribution were formed, when a small volume of an aqueous polymer solution below the CP was added to a large volume of heated water. In this way the thermosensitive block copolymers rapidly pass their CP ('heat shock' procedure), resulting in small and stable nanoparticles.

Growth of indium gallium arsenide thin film on silicon substrate by MOCVD technique

NASA Astrophysics Data System (ADS)

Chowdhury, Sisir; Das, Anish; Banerji, Pallab

2018-05-01

Indium gallium arsenide (InGaAs) thin film with indium phosphide (InP) buffer has been grown on p-type silicon (100) by Metal Organic Chemical Vapor Deposition (MOCVD) technique. To get a lattice matched substrate an Indium Phosphide buffer thin film is deposited onto Si substrate prior to InGaAs growth. The grown films have been investigated by UV-Vis-NIR reflectance spectroscopy. The band gap energy of the grown InGaAs thin films determined to be 0.82 eV from reflectance spectrum and the films are found to have same thickness for growth between 600 °C and 650 °C. Crystalline quality of the grown films has been studied by grazing incidence X-ray diffractometry (GIXRD).

Glutamate spillover drives endocannabinoid production and inhibits GABAergic transmission in the Substantia Nigra pars compacta.

PubMed

Freestone, Peter S; Guatteo, Ezia; Piscitelli, Fabiana; di Marzo, Vincenzo; Lipski, Janusz; Mercuri, Nicola B

2014-04-01

Endocannabinoids (eCBs) modulate synaptic transmission in the brain, but little is known of their regulatory role in nigral dopaminergic neurons, and whether transmission to these neurons is tonically inhibited by eCBs as seen in some other brain regions. Using whole-cell recording in midbrain slices, we observed potentiation of evoked IPSCs (eIPSCs) in these neurons after blocking CB1 receptors with rimonabant or LY-320,135, indicating the presence of an eCB tone reducing inhibitory synaptic transmission. Increased postsynaptic calcium buffering and block of mGluR1 or postsynaptic G-protein coupled receptors prevented this potentiation. Increasing spillover of endogenous glutamate by inhibiting uptake attenuated eIPSC amplitude, while enhancing the potentiation by rimonabant. Group I mGluR activation transiently inhibited eIPSCs, which could be prevented by GDP-β-S, increased calcium buffering or rimonabant. We explored the possibility that the dopamine-derived eCB N-arachidonoyl dopamine (NADA) is involved. The eCB tone was abolished by preventing dopamine synthesis, and enhanced by l-DOPA. It was not detected in adjacent non-dopaminergic neurons. Preventing 2-AG synthesis did not affect the tone, while inhibition of NADA production abolished it. Quantification of ventral midbrain NADA suggested a basal level that increased following prolonged depolarization or mGluR activation. Since block of the tone was not always accompanied by attenuation of depolarization-induced suppression of inhibition (DSI) and vice versa, our results indicate DSI and the eCB tone are mediated by distinct eCBs. This study provides evidence that dopamine modulates the activity of SNc neurons not only by conventional dopamine receptors, but also by CB1 receptors, potentially via NADA. Copyright © 2013 Elsevier Ltd. All rights reserved.

Achieving Bidirectional Long Delays In Pulmonary Vein Antral Lines Prior To Bidirectional Block In Patients With Paroxysmal Atrial Fibrillation (The Bi-Bi Technique For Atrial Fibrillation Ablation).

PubMed

Mina, Adel F; Warnecke, Nicholas L

2016-01-01

Background: Pulmonary Vein Antral isolation (PVAI) is currently the standard of care for both paroxysmal and persistent atrial fibrillation ablation. Reconnection to the pulmonary vein is the most common cause of recurrence of atrial fibrillation. Achieving the endpoint of bidirectional block (BDB) for cavotricuspid isthmus dependant flutter has improved our outcomes for atrial flutter ablation. With this we tried to achieve long delays in the pulmonary veins antral lines prior to complete isolation comparable to those delays found in patient with bidirectional block of atrial flutter lines. Study Objective: The objective of this paper was to evaluate feasibility and efficacy of achieving Bidirectional long delays in pulmonary vein antral lines prior to Bidirectional Block in patient with paroxysmal atrial fibrillation. Method: A retrospective analysis was performed on patients who had paroxysmal atrial fibrillation procedures at Unity Point Methodist from January 2015 to January 2016. 20 consecutive patients with paroxysmal atrial fibrillation who had AF ablation using the Bi-Bi technique were evaluated. Result: Mean age was 63, number of antiarrhythmic used prior to ablation was 1.4, mean left atrial size was 38 mm. Mean chads score was 1.3. Mean EF was 53%. Long delays in the left antral circumferential lines were achieved with mean delay of 142 milliseconds +/-100. Also long delays in the right antral circumferential lines were achieved with mean delay of 150 milliseconds +/-80. 95 % (19/20) of patients were free of any atrial arrhythmias and were off antiarrhythmic medications for AF post procedure. There was only one transient complication in one patient who developed a moderate pericardial effusion that was successfully drained with no hemodynamic changes. The only patient who had recurrence was found to have asymptomatic AF with burden on his device <1%, this patient was also found to have non PV triggers for his AF. In patients with only PV triggered AF success rate was 100%. Conclusion: Achievement of Bidirectional long delays in pulmonary vein antral lines prior to Bidirectional Block in patient with paroxysmal atrial fibrillation is feasible and highly effective technique in this small cohort of patients studied. We also outlined the procedure in details.

Nursing Student Perceptions Regarding Simulation Experience Sequencing.

PubMed

Woda, Aimee A; Gruenke, Theresa; Alt-Gehrman, Penny; Hansen, Jamie

2016-09-01

The use of simulated learning experiences (SLEs) have increased within nursing curricula with positive learning outcomes for nursing students. The purpose of this study is to explore nursing students' perceptions of their clinical decision making (CDM) related to the block sequencing of different patient care experiences, SLEs versus hospital-based learning experiences (HLEs). A qualitative descriptive design used open-ended survey questions to generate information about the block sequencing of SLEs and its impact on nursing students' perceived CDM. Three themes emerged from the data: Preexperience Anxiety, Real-Time Decision Making, and Increased Patient Care Experiences. Nursing students identified that having SLEs prior to HLEs provided several benefits. Even when students preferred SLEs prior to HLEs, the sequence did not impact their CDM. This suggests that alternating block sequencing can be used without impacting the students' perceptions of their ability to make decisions. [J Nurs Educ. 2016;55(9):528-532.]. Copyright 2016, SLACK Incorporated.

Administration of the non-steroidal anti-inflammatory drug ibuprofen increases macrophage concentrations but reduces necrosis during modified muscle use

NASA Technical Reports Server (NTRS)

Cheung, E. V.; Tidball, J. G.

2003-01-01

OBJECTIVE: To test the hypothesis that ibuprofen administration during modified muscle use reduces muscle necrosis and invasion by select myeloid cell populations. METHODS: Rats were subjected to hindlimb unloading for 10 days, after which they experienced muscle reloading by normal weight-bearing to induce muscle inflammation and necrosis. Some animals received ibuprofen by intraperitoneal injection 8 h prior to the onset of muscle reloading, and then again at 8 and 16 h following the onset of reloading. Other animals received buffer injection at 8 h prior to reloading and then ibuprofen at 8 and 16 h following the onset of reloading. Control animals received buffer only at each time point. Quantitative immunohistochemical analysis was used to assess the presence of necrotic muscle fibers, total inflammatory infiltrate, neutrophils, ED1+ macrophages and ED2+ macrophages at 24 h following the onset of reloading. RESULT: Administration of ibuprofen beginning 8 h prior to reloading caused significant reduction in the concentration of necrotic fibers, but increased the concentration of inflammatory cells in muscle. The increase in inflammatory cells was attributable to a 2.6-fold increase in the concentration of ED2+ macrophages. Animals treated with ibuprofen 8 h following the onset of reloading showed no decrease in muscle necrosis or increase in ED2+ macrophage concentrations. CONCLUSION: Administration of ibuprofen prior to increased muscle loading reduces muscle damage, but increases the concentration of macrophages that express the ED2 antigen. The increase in ED2+ macrophage concentration and decrease in necrosis may be mechanistically related because ED2+ macrophages have been associated with muscle regeneration and repair.

Context Blocking in Rat Autoshaping: Sign-Tracking versus Goal-Tracking

ERIC Educational Resources Information Center

Costa, Daniel S. J.; Boakes, Robert A.

2009-01-01

Prior experience of unsignaled food can interfere with subsequent acquisition by birds of autoshaped key-pecking at a signal light. This has been understood to indicate that unsignaled food results in context conditioning, which blocks subsequent learning about the keylight-food relationship. In the present experiment with rats lever insertion as…

All Work and No PLA Makes Jack a Dull Boy

ERIC Educational Resources Information Center

Popova-Gonci, Viktoria

2009-01-01

In this article, the author presents an assortment of approaches--building blocks--commonly used in Prior Learning Assessment (PLA) practices (this list is certainly not comprehensive): (1) course matching (comparing course requirements to a student's prior learning experiences); (2) student's ability to articulate learning gained from…

Forecasting Maintenance Shortcomings of a Planned Equipment Density Listing in Support of Expeditionary Missions

DTIC Science & Technology

2017-06-01

importantly, it examines the methodology used to build the class IX block embarked on ship prior to deployment. The class IX block is defined as a repository...compared to historical data to evaluate model and simulation outputs. This thesis provides recommendations on improving the methodology implemented in...improving the level of organic support available to deployed units. More importantly, it examines the methodology used to build the class IX block

Soil Parameter Mapping and Ad Hoc Power Analysis to Increase Blocking Efficiency Prior to Establishing a Long-Term Field Experiment

PubMed Central

Collins, Doug; Benedict, Chris; Bary, Andy; Cogger, Craig

2015-01-01

The spatial heterogeneity of soil and weed populations poses a challenge to researchers. Unlike aboveground variability, below-ground variability is more difficult to discern without a strategic soil sampling pattern. While blocking is commonly used to control environmental variation, this strategy is rarely informed by data about current soil conditions. Fifty georeferenced sites were located in a 0.65 ha area prior to establishing a long-term field experiment. Soil organic matter (OM) and weed seed bank populations were analyzed at each site and the spatial structure was modeled with semivariograms and interpolated with kriging to map the surface. These maps were used to formulate three strategic blocking patterns and the efficiency of each pattern was compared to a completely randomized design and a west to east model not informed by soil variability. Compared to OM, weeds were more variable across the landscape and had a shorter range of autocorrelation, and models to increase blocking efficiency resulted in less increase in power. Weeds and OM were not correlated, so no model examined improved power equally for both parameters. Compared to the west to east blocking pattern, the final blocking pattern chosen resulted in a 7-fold increase in power for OM and a 36% increase in power for weeds. PMID:26247056

A comparison of buffered lidocaine versus ELA-Max before peripheral intravenous catheter insertions in children.

PubMed

Luhmann, Janet; Hurt, Sarah; Shootman, Mario; Kennedy, Robert

2004-03-01

Peripheral intravenous catheter (PIV) insertion is a common, painful experience for many children in the pediatric emergency department. Although local anesthetics such as injected buffered lidocaine have been shown to be effective at reducing pain and anxiety associated with PIV insertion, they are not routinely used. ELA-Max, a topical local anesthetic, has the advantage of needle-free administration but has not been compared with buffered lidocaine for PIV insertion. To compare the reduction of pain and anxiety during PIV insertion provided by subcutaneous buffered 1% lidocaine or topical ELA-Max in children. A randomized trial in children 4 to 17 years old undergoing PIV insertion with 22-gauge catheters was conducted. Children received either buffered lidocaine or ELA-Max. Buffered lidocaine was administered by using 30-gauge needles to inject 0.1 to 0.2 mL subcutaneously just before PIV insertion. ELA-Max was applied to the skin and occluded with Tegaderm 30 minutes before PIV insertion. Self-reported Visual Analog Scale (VAS) questionnaires (rating on a scale of 1-10; 1 = no pain, anxiety) were completed by patients and their parents before PIV insertion to assess baseline perceptions about pain and anxiety associated with PIV insertion and immediately after PIV insertion to assess pain and anxiety associated with the experience. After PIV insertion, the nurse who inserted the PIV also completed a VAS questionnaire assessing technical difficulty and satisfaction with the local anesthesia. A blinded observer also completed a VAS questionnaire to assess pain and anxiety associated with the PIV insertion. Data were analyzed by using chi2 and t tests. Sixty-nine subjects were enrolled, and questionnaires were competed by all (mean age: 12.1 +/- 4.5 years; 61% female). There were no differences for buffered lidocaine and ELA-Max groups in age, gender, race, prior IV experience, or baseline pain and anxiety. There were no significant differences between buffered lidocaine and ELA-Max in mean pain and anxiety after PIV insertion by patient, parent, and blinded observer ratings. Nurse ratings of technical difficulty, number of PIV-insertion attempts, and satisfaction with local anesthesia also were not significantly different for buffered lidocaine and ELA-Max groups. ELA-Max provided similar pain and anxiety reduction during PIV insertion in children compared with injected buffered lidocaine. Technical difficulty and satisfaction by nurses inserting the PIV also were similar.

Effects of AN Alfalfa (medicago Sativa) Buffer Strip on Leached δ15NNITRATE Values: Implications for Management of Hydrologic N Losses

NASA Astrophysics Data System (ADS)

Kelley, C. J.; Keller, C. K.; Smith, J. L.; Evans, R. D.; Harlow, B.

2011-12-01

Buffer strips are commonly used to decrease agricultural runoff with the objective of limiting sediment and agrochemicals fluxes to surface waters. The objective of this study was to determine the effects of an alfalfa buffer strip on the magnitude and source(s) of leached nitrate from a dryland agricultural field. Previous research at the Cook Agronomy Farm has inferred two sources of nitrate in tile drain discharge, a high-discharge-season (January through May) synthetic fertilizer source, and a low-discharge-season (June through December) soil organic nitrogen source. This study examines how a change in management strategy and crop species alters the low discharge season nitrate source. In the spring of 2006 an alfalfa buffer strip approximately 20 m wide was planted running approximately north-south in the lowland portion of a 12 ha tile-drained field bordering a ditch that drains into Missouri Flat Creek. Three-year (2003 through 2005) average NO3--N flux prior to the planting of the alfalfa buffer strip was ~0.40 kg ha-1 year-1. After planting, the three-year (2006 through 2008) average NO3--N flux was ~0.38 kg ha-1 year-1. The lack of evident buffer-strip influence on the fluxes may be due in part to the large variation in precipitation amounts and timing that control water flows through the system. Three-year average δ15Nnitrate values for the tile drain pre and post planting of the alfalfa buffer strip were 6.9 ± 1.1 % and 4.2 ± 0.9 % respectively. We hypothesize that the significant difference indicates that the alfalfa strip affects the source of leached nitrate. Before planting the alfalfa buffer strip, the interpreted source of nitrate was mineralization of soil organic nitrogen from non-N2 fixing crops (spring and summer wheat varieties). After planting the alfalfa buffer strip, the source of nitrate was interpreted to be a mixture of mineralized soil organic nitrogen from N2 fixing alfalfa and non-N2 fixing crops. Further work is needed to test alternative explanations for the observed isotopic shift. This study suggests that the effects of leguminous buffer strips on nutrient fluxes are not simple, and may depend on combinations of hydrologic and pedo-geologic factors.

The stress-buffering effects of functional social support on ambulatory blood pressure.

PubMed

Bowen, Kimberly S; Uchino, Bert N; Birmingham, Wendy; Carlisle, McKenzie; Smith, Timothy W; Light, Kathleen C

2014-11-01

Social support is a reliable predictor of cardiovascular health. According to the buffering hypothesis, stress is 1 mechanism by which support is able to affect physiological processes. However, most of the experimental evidence for the hypothesis comes from laboratory studies. Ambulatory blood pressure (ABP) protocols examine participants in their natural environment, where they are more likely to encounter personally relevant real-world stressors. Furthermore, prior work shows that examining support by its specific functional components reveals additional independent links to health. The current study aimed to examine the stress-buffering effects of functional social support on ABP. One hundred eighty-eight participants completed a 1-day ABP assessment along with measures of functional social support and both global perceived stress and momentary stress at time of reading. RESULTS indicated main effects for both stress measures. Global support, emotional, tangible, and informational support only moderated the effects of momentary stress, but not global stress, in predicting ABP. Informational support was the most consistent stress-buffering predictor of ABP, predicting both ambulatory systolic and diastolic blood pressure. The predicted values in ABP for informational support achieved health-relevant differences, emphasizing the value of examining functional support beyond global support alone. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Capillary-Channeled Polymer (C-CP) Fibers as a Stationary Phase for Sample Clean-Up of Protein Solutions for Matrix-Assisted Laser/Desorption Ionization Mass Spectrometry

NASA Astrophysics Data System (ADS)

Manard, Benjamin T.; Marcus, R. Kenneth

2012-08-01

Capillary-channeled polymer (C-CP) fibers are employed in a micropipette tip format to affect a stationary phase for the solid phase extraction (SPE) of proteins from buffer solutions prior to MALDI-MS analysis. Proteins readily adsorb to the polypropylene (PP) C-CP fibers while buffer species are easily washed off the tips using DI-H2O. Elution of the solutes is achieved with an aliquot of 50:50 ACN:H2O, which is compatible with the subsequent spotting on the MALDI target with the matrix solution. Lysozyme and cytochrome c are used as test species, with a primary buffer composition of 100 mM Tris-HCl. In this case, direct MALDI-MS produces no discernible protein signals. SPE on the C-CP fibers yields high fidelity mass spectra for 1 μL sample volumes. Limits of detection for cytochrome c in 100 mM Tris-HCl are on the order of 40 nM. Extraction of cytochrome c from buffer concentrations of up to 1 M Tris-HCl, provides signal recoveries that are suppressed by only ~50 % versus neat protein solutions. Finally, extraction of 3.1 μM cytochrome c from a synthetic urine matrix exhibits excellent recovery.

Developing procedures for the large-scale purification of human serum butyrylcholinesterase.

PubMed

Saxena, Ashima; Luo, Chunyuan; Doctor, Bhupendra P

2008-10-01

Human serum butyrylcholinesterase (Hu BChE) is the most viable candidate for the prophylactic treatment of organophosphate poisoning. A dose of 200 mg/70 kg is predicted to protect humans against 2x LD(50) of soman. Therefore, the aim of this study was to develop procedures for the purification of gram quantities of this enzyme from outdated human plasma or Cohn Fraction IV-4. The purification of Hu BChE was accomplished by batch adsorption on procainamide-Sepharose-CL-4B affinity gel followed by ion-exchange chromatography on a DEAE-Sepharose column. For the purification of enzyme from Cohn Fraction IV-4, it was resuspended in 25 mM sodium phosphate buffer, pH 8.0, and fat was removed by decantation, prior to batch adsorption on procainamide-Sepharose gel. In both cases, the procainamide gel was thoroughly washed with 25 mM sodium phosphate buffer, pH 8.0, containing 0.05 M NaCl, and the enzyme was eluted with the same buffer containing 0.1 M procainamide. The enzyme was dialyzed and the pH was adjusted to 4.0 before loading on the DEAE column equilibrated in sodium acetate buffer, pH 4.0. The column was thoroughly washed with 25 mM sodium phosphate buffer, pH 8.0 containing 0.05 M NaCl before elution with a gradient of 0.05-0.2M NaCl in the same buffer. The purity of the enzyme following these steps ranged from 20% to 40%. The purity of the enzyme increased to >90% by chromatography on an analytical procainamide affinity column. Results show that Cohn Fraction IV-4 is a much better source than plasma for the large-scale isolation of purified Hu BChE.

Resuscitation by Ferrioxamine E of Stressed Salmonella enterica Serovar Typhimurium from Soil and Water Microcosms

PubMed Central

Reissbrodt, R.; Heier, H.; Tschäpe, H.; Kingsley, R. A.; Williams, P. H.

2000-01-01

Storage of Salmonella enterica serovar Typhimurium strains in soil and water microcosms resulted in loss of culturability on standard plating media. Prior incubation in buffered peptone water supplemented with ferrioxamine E markedly extended the time that bacteria were recoverable by plating, except in the case of mutants deficient in ferrioxamine E uptake. PMID:10966440

Why Do You Work with Struggling Students? Teacher Perceptions of Meaningful Work in Trauma-Impacted Classrooms

ERIC Educational Resources Information Center

Brunzell, Tom; Stokes, Helen; Waters, Lea

2018-01-01

This study contributed new findings to the construct of meaningful work (MW) and negative impacts on MW. In other professional samples, finding meaning in work has been shown to be an effective buffer when facing workplace adversity. However, prior investigation has neither identified nor explored the specific sources and mechanisms of meaningful…

Heat-sterilized PD fluid blocks leukocyte adhesion and increases flow velocity in rat peritoneal venules.

PubMed

Jonasson, P; Bagge, U; Wieslander, A; Braide, M

1996-01-01

Data from cell culture experiments indicate that heat sterilization of peritoneal dialysis (PD) fluids produces cytotoxic glucose degradation products. The present vital microscopic study investigated the effects of different sterilization methods on the biocompatibility of PD fluids. Thus, heat-sterilized (commercially obtained and experimentally produced) and filter-sterilized PD fluids (pH = 5.30-5.40; 1.5% glucose) were compared with Tyrode buffer, with respect to the effects on microvascular blood flow velocity and leukocyte adhesion in the rat mesentery. Exteriorization of the mesentery produced a mild inflammation, known from the literature and characterized by the adhesive rolling of leukocytes along venular walls. Superfusion of the mesentery with filter-sterilized PD fluid had no significant effects on leukocyte rolling or flow velocity in venules 25-40 microns in diameter compared with buffer superfusion. Heat-sterilized PD fluid decreased the concentration of rolling leukocytes and increased flow velocity significantly, as compared with buffer and filter-sterilized PD fluid. The results indicate that heat sterilization of PD fluids produces substances that interact with microvascular tone and leukocyte-endothelial adhesion, which hypothetically could impair the acute, granulocyte-mediated defense against bacterial infections.

NASA ARCH- A FILE ARCHIVAL SYSTEM FOR THE DEC VAX

NASA Technical Reports Server (NTRS)

Scott, P. J.

1994-01-01

The function of the NASA ARCH system is to provide a permanent storage area for files that are infrequently accessed. The NASA ARCH routines were designed to provide a simple mechanism by which users can easily store and retrieve files. The user treats NASA ARCH as the interface to a black box where files are stored. There are only five NASA ARCH user commands, even though NASA ARCH employs standard VMS directives and the VAX BACKUP utility. Special care is taken to provide the security needed to insure file integrity over a period of years. The archived files may exist in any of three storage areas: a temporary buffer, the main buffer, and a magnetic tape library. When the main buffer fills up, it is transferred to permanent magnetic tape storage and deleted from disk. Files may be restored from any of the three storage areas. A single file, multiple files, or entire directories can be stored and retrieved. archived entities hold the same name, extension, version number, and VMS file protection scheme as they had in the user's account prior to archival. NASA ARCH is capable of handling up to 7 directory levels. Wildcards are supported. User commands include TEMPCOPY, DISKCOPY, DELETE, RESTORE, and DIRECTORY. The DIRECTORY command searches a directory of savesets covering all three archival areas, listing matches according to area, date, filename, or other criteria supplied by the user. The system manager commands include 1) ARCHIVE- to transfer the main buffer to duplicate magnetic tapes, 2) REPORTto determine when the main buffer is full enough to archive, 3) INCREMENT- to back up the partially filled main buffer, and 4) FULLBACKUP- to back up the entire main buffer. On-line help files are provided for all NASA ARCH commands. NASA ARCH is written in DEC VAX DCL for interactive execution and has been implemented on a DEC VAX computer operating under VMS 4.X. This program was developed in 1985.

Fundamental properties of monolithic bentonite buffer material formed by cold isostatic pressing for high-level radioactive waste repository

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

Kawakami, S.; Yamanaka, Y.; Kato, K.

1999-07-01

The methods of fabrication, handling, and emplacement of engineered barriers used in a deep geological repository for high level radioactive waste should be planned as simply as possible from the engineering and economic viewpoints. Therefore, a new concept of a monolithic buffer material around a waste package have been proposed instead of the conventional concept with the use of small blocks, which would decrease the cost for buffer material. The monolithic buffer material is composed of two parts of highly compacted bentonite, a cup type body and a cover. As the forming method of the monolithic buffer material, compaction bymore » the cold isostatic pressing process (CIP) has been employed. In this study, monolithic bentonite bodies with the diameter of about 333 mm and the height of about 455 mm (corresponding to the approx. 1/5 scale for the Japanese reference concept) were made by the CIP of bentonite powder. The dry densities: {rho}d of the bodies as a whole were measured and the small samples were cut from several locations to investigate the density distribution. The swelling pressure and hydraulic conductivity as function of the monolithic body density for CIP-formed specimens were also measured. High density ({rho}d: 1.4--2.0 Mg/m{sup 3}) and homogeneous monolithic bodies were formed by the CIP. The measured results of the swelling pressure (3--15 MPa) and hydraulic conductivity (0.5--1.4 x 10{sup {minus}13} m/s) of the specimens were almost the same as those for the uniaxial compacted bentonite in the literature. It is shown that the vacuum hoist system is an applicable handling method for emplacement of the monolithic bentonite.« less

Thermodynamic and structural aspects of novel 1,2,4-thiadiazoles in solid and biological mediums.

PubMed

Perlovich, German L; Proshin, Alexey N; Volkova, Tatyana V; Bui, Cong Trinh; Bachurin, Sergey O

2011-10-03

Novel 1,2,4-thiadiazoles were synthesized. Crystal structures of these compounds were solved by X-ray diffraction experiments, and comparative analysis of packing architecture and hydrogen bond networks was carried out. Thermodynamic aspects of sublimation processes of the compounds under study were analyzed using temperature dependencies of vapor pressure. Thermophysical characteristics of the molecular crystals were obtained and compared with the sublimation and structural parameters. The melting points correlate with sublimation Gibbs energies. Moreover, an increase of donor-acceptor interactions in crystal structures leads to growth of Gibbs energy values. Relationships between the melting points and the fragmental contributions to the packing energies were established: R(1)-R(4) fragmental interactions are responsible for the fusion processes of this class of compounds. Solubility and solvation processes of 1,2,4-thiadiazoles in buffer, n-hexane and n-octanol were studied within a wide range of temperature intervals, and their thermodynamic functions were calculated. Specific and nonspecific interactions of molecules resolved in crystals and solvents were estimated and compared. It was found that the melting points correlate with sublimation Gibbs energies. Distribution processes of compounds in buffer/n-octanol and buffer/n-hexane systems (describing different types of membranes) were investigated. Transfer processes of the studied molecules from the buffer to n-octanol/n-hexane phases were analyzed by the diagram method with evaluation of the enthalpic and entropic terms. This approach allowed us to design drug molecules with optimal passive transport properties. Calcium-blocking properties of the substances were evaluated. The trend between the ability to inhibit Glu-Ca uptake and the distribution coefficients in buffer/hexane system was observed.

Band alignments of different buffer layers (CdS, Zn(O,S), and In{sub 2}S{sub 3}) on Cu{sub 2}ZnSnS{sub 4}

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

Yan, Chang; Liu, Fangyang; Song, Ning

2014-04-28

The heterojunctions of different n-type buffers, i.e., CdS, Zn(O,S), and In{sub 2}S{sub 3} on p-type Cu{sub 2}ZnSnS{sub 4} (CZTS) were investigated using X-ray Photoelectron Spectroscopy (XPS) and Near Edge X-ray Absorption Fine Structure (NEXAFS) Measurements. The band alignment of the heterojunctions formed between CZTS and the buffer materials was carefully measured. The XPS data were used to determine the Valence Band Offsets (VBO) of different buffer/CZTS heterojunctions. The Conduction Band Offset (CBO) was calculated indirectly by XPS data and directly measured by NEXAFS characterization. The CBO of the CdS/CZTS heterojunction was found to be cliff-like with CBO{sub XPS} = −0.24 ± 0.10 eV and CBO{submore » NEXAFS} = −0.18 ± 0.10 eV, whereas those of Zn(O,S) and In{sub 2}S{sub 3} were found to be spike-like with CBO{sub XPS} = 0.92 ± 0.10 eV and CBO{sub NEXAFS} = 0.87 ± 0.10 eV for Zn(O,S)/CZTS and CBO{sub XPS} = 0.41 ± 0.10 eV for In{sub 2}S{sub 3}/CZTS, respectively. The CZTS photovoltaic device using the spike-like In{sub 2}S{sub 3} buffer was found to yield a higher open circuit voltage (Voc) than that using the cliff-like CdS buffer. However, the CBO of In{sub 2}S{sub 3}/CZTS is slightly higher than the optimum level and thus acts to block the flow of light-generated electrons, significantly reducing the short circuit current (Jsc) and Fill Factor (FF) and thereby limiting the efficiency. Instead, the use of a hybrid buffer for optimization of band alignment is proposed.« less

The Rebirth of a World Power? German Unification and the Future of European Security

DTIC Science & Technology

1990-12-01

Government. 17 COSATI CODES 18 SUBJECT TERMS (Continue on reverse if necessary and identify by block number) FIELD GROUP SUB- GROUP German unification...in the balance of power system. Germany (and Prussia) was used as a territorial "shock absorber" to maintain a buffer between the great powers--a...European statecraft was not pressured by internal problems which later forced governments to take actions that aroused the suspicions and fears of the

Hybrid Quantum Cascade Lasers on Silicon-on-Sapphire

DTIC Science & Technology

2016-11-23

on-SOS devices mounted on a copper heat sink. The liquid crystal thermal absorber is attached to block mid-IR emission from any sections of the laser...directions. 2. Statement of the problem studied Short-wavelength infrared (SWIR, ~1-3 m) photonics systems based on silicon-on- insulator (SOI...Table 1. Layer type Layer thickness and doping Thickness (nm) Doping (cm-3) InP substrate 350000 Semi- insulating InP buffer layer 2000 2.00E

Multiprocessor Real-Time Locking Protocols for Replicated Resources

DTIC Science & Technology

2016-07-01

circular buffer of slots, each representing a discrete segment of time . For example, if the maintenance of a timing wheel occurs af- ter an interrupt ...Experimental Evaluation To evaluate Algs. 2, 3, and 4, we conducted a series of ex- periments in which we measured relevant overheads and blocking times . We...Multiprocessor Real- Time Locking Protocols for Replicated Resources ∗ Catherine E. Jarrett1, Kecheng Yang1, Ming Yang1, Pontus Ekberg2, and James H

A Self-Assembling Protein Hydrogel Technology for Enzyme Incorporation onto Electrodes in Biofuel Cells

DTIC Science & Technology

2015-10-26

amount of the product J and the unreacted N/C in the same lane. Figure 2. Crystal structure of Tip1-Tip1lig ( PDB code: 3IDW). (A...stability (able to retain its trimeric quaternary structure in solutions after boiling in SDS buffer). We reasoned that its very strong...109, 10 is a flexible polyanionic linker and was incorporated as the midblock for water retention. Mixing of the two protein block copolymers

Electrical detection and quantification of single and mixed DNA nucleotides in suspension

NASA Astrophysics Data System (ADS)

Ahmad, Mahmoud Al; Panicker, Neena G.; Rizvi, Tahir A.; Mustafa, Farah

2016-09-01

High speed sequential identification of the building blocks of DNA, (deoxyribonucleotides or nucleotides for short) without labeling or processing in long reads of DNA is the need of the hour. This can be accomplished through exploiting their unique electrical properties. In this study, the four different types of nucleotides that constitute a DNA molecule were suspended in a buffer followed by performing several types of electrical measurements. These electrical parameters were then used to quantify the suspended DNA nucleotides. Thus, we present a purely electrical counting scheme based on the semiconductor theory that allows one to determine the number of nucleotides in a solution by measuring their capacitance-voltage dependency. The nucleotide count was observed to be similar to the multiplication of the corresponding dopant concentration and debye volume after de-embedding the buffer contribution. The presented approach allows for a fast and label-free quantification of single and mixed nucleotides in a solution.

Triblock copolyampholytes from 5-(N,N-dimethyl amino)isoprene styrene, and methacrylic acid: Synthesis and solution properties

NASA Astrophysics Data System (ADS)

Bieringer, R.; Abetz, V.; Müller, A. H. E.

ABC triblock copolymers of the type poly[5-(N,N-dimethyl amino)isoprene]-block-polystyrene-block-poly(tert-butyl methacrylate) (AiST) were synthesized and hydrolyzed to yield poly[5-(N,N-dimethyl amino)isoprene]-block-polystyrene-block-poly(methacrylic acid) (AiSA) triblock copolyampholytes. Due to a complex solubility behavior the solution properties of these materials had to be investigated in THF/water solvent mixtures. Potentiometric titrations of AiSA triblock copolyampholytes showed two inflection points with the A block being deprotonated prior to the Ai hydrochloride block thus forming a polyzwitterion at the isoelectric point (iep). The aggregation behavior was studied by dynamic light scattering (DLS) and freeze-fracture/transmission electron microscopy (TEM). Large vesicular structures with almost pH-independent radii were observed.

Paracervical block for pain control in first-trimester surgical abortion: a randomized controlled trial.

PubMed

Renner, Regina-Maria; Nichols, Mark D; Jensen, Jeffrey T; Li, Hong; Edelman, Alison B

2012-05-01

Despite lack of efficacy data, the majority of first-trimester surgical abortions are performed with a paracervical block. Women may be unnecessarily exposed to a painful injection and potentially noxious medication. Our objective was to estimate the effect of a paracervical block and the effect of gestational age on patient pain perception. This was a randomized, single-blind trial of patients undergoing abortion receiving paracervical block or sham stratified by gestational age (early: less than 8 weeks of gestation, n=60; late: 8-10 6/7 weeks of gestation, n=60). Premedicated with ibuprofen and lorazepam, all participants received 2 mL 1% buffered lidocaine injected at the tenaculum site followed by a slow, deep injection of 18 mL at four sites (block) or no injection (sham) with a 3-minute wait. The primary outcome was dilation pain (100-mm visual analog scale). Secondary outcomes included pain at additional time points, satisfaction, need for more analgesics, and adverse events. Full enrollment occurred (n=120). We used intent-to-treat analysis. Demographics did not differ between groups. Paracervical block administration was painful (mean 55 mm compared with sham 30 mm, P<.001) but decreased dilation pain (42 mm compared with 79 mm, P<.001) and aspiration pain (63mm compared with 89 mm, P<.001). These results were consistent for both gestational age strata; however, paracervical block benefit was greater at an earlier gestation. Satisfaction scores with pain control and the procedure were significantly higher in the block group. Although paracervical block is painful, it reduces first-trimester abortion pain regardless of gestational age, but the benefit on dilation pain was greater at earlier gestations. ClinicalTrials.gov, www.clinicaltrials.gov, NCT01094366. I.

The Minorca Basin: a buffer zone between the Valencia and Liguro-Provençal Basins (NW Mediterranean Sea)

NASA Astrophysics Data System (ADS)

Pellen, Romain; Aslanian, Daniel; Rabineau, Marina; Leroux, Estelle; Gorini, Christian; Silenziario, Carmine; Blanpied, Christian; Rubino, Jean-Loup

2017-04-01

The present-day compartmented Mediterranean physiography is inherited from the last 250 Ma kinematic plate evolution (Eurasian, Africa, Iberic and Nubia plates) which implied the formation of orogenic chains, polyphased basins, and morphological - geodynamic thresholds. The interactions between these entities are strongly debated in the North-Western Mediterranean area. Several Neogene reconstructions have been proposed for the Valencia basin depending of the basin segmentation where each model imply a different subsidence, sedimentary, and palaeo-environmental evolution. Our study propose a new kinematic model for the Valencia Basin (VB) that encompasses the sedimentary infill, vertical movement and basin segmentation. Detailed analyses of seismic profiles and boreholes in the VB reveal a differentiated basin, the Minorca Basin (MB), lying between the old Mesozoic Valencia Basin sensu strico (VBss) and the young Oligocene Liguro-Provencal Basin (LPB) (Pellen et al., 2016). The relationship between these basins is shown through the correlation of four Miocene-to-present-day megasequences. The Central and North Balearic Fracture Zones (CFZ and NBFZ) that border the MB represent two morphological and geodynamical thresholds that created an accommodation in steps between the three domains. Little to no horizontal Neogene movements have been found for the Ibiza and Majorca Islands and imply a vertical "sag" subsidence. In contrast, the counterclockwise movement of the Corso-Sardinian blocks induced a counterclockwise movement of the Minorca block towards the SE along the CFZ and NBFZ, during the exhumation of lower continental crust in the LPB. The South-Eastward Minorca block translation stops when the first atypical oceanic crust occurs. The influence of the Neogene Betic compressional phase is thus limited to the VBss on the basis of a different MB origin. This new understanding places the AlKaPeCa blocks northeastward of the present-day Alboran Area. Both NW-SE and NE-SW Neogene blocks rotation proposed in earlier studies are therefore questioned (Pellen et al., 2016). A better kinematic understanding of the NW Mediterranean area is possible through the study of the South Balearic margin and Algerian basins. Pellen, R., Aslanian, D., Rabineau, M., Leroux, E., Gorini, C., Silenzario, C., Blanpied, C., Rubino J-L., 2016. The Minorca Basin: a buffer zone between Valencia and Provençal Basins, Terra Nova. doi: 10.1111/ter.12215

On Reducing Delay in Mesh-Based P2P Streaming: A Mesh-Push Approach

NASA Astrophysics Data System (ADS)

Liu, Zheng; Xue, Kaiping; Hong, Peilin

The peer-assisted streaming paradigm has been widely employed to distribute live video data on the internet recently. In general, the mesh-based pull approach is more robust and efficient than the tree-based push approach. However, pull protocol brings about longer streaming delay, which is caused by the handshaking process of advertising buffer map message, sending request message and scheduling of the data block. In this paper, we propose a new approach, mesh-push, to address this issue. Different from the traditional pull approach, mesh-push implements block scheduling algorithm at sender side, where the block transmission is initiated by the sender rather than by the receiver. We first formulate the optimal upload bandwidth utilization problem, then present the mesh-push approach, in which a token protocol is designed to avoid block redundancy; a min-cost flow model is employed to derive the optimal scheduling for the push peer; and a push peer selection algorithm is introduced to reduce control overhead. Finally, we evaluate mesh-push through simulation, the results of which show mesh-push outperforms the pull scheduling in streaming delay, and achieves comparable delivery ratio at the same time.

Functional characterization of intracellular pH regulators responsible for acid extrusion in human radial artery smooth muscle cells.

PubMed

Lee, Chung-Yi; Tsai, Yi-Ting; Chang, Chung-Yi; Chang, Yi-Yu; Cheng, Tzu-Hurng; Tsai, Chien-Sung; Loh, Shih-Hurng

2014-10-31

Intracellular pH (pHi) is a critical factor influencing many important cellular functions. Acid extrusion carriers such as an Na⁺/H⁺ exchanger (NHE) Na⁺/HCO₃⁻ cotransporter (NBC) and monocarboxylate transporters (MCT) can be activated when cells are in an acidic condition (pHi < 7.1). Human radial artery smooth muscle cells (HRASMC) is an important conduit in coronary artery bypass graft surgery. However, such far, the pHi regulators have not been characterized in HRASMCs. We therefore investigated the mechanism of pHi recovery from intracellular acidosis and alkalosis, induced by NH₄Cl-prepulse and Na-acetate-prepulse, respectively, using intracellular 2',7'-bis(2-carboxethyl)-5(6)- carboxy-fluorescein (BCECF)-fluorescence in HRASMCs. Cultured HRASMCs were derived from the segments of human radial artery that were obtained from patients undergoing bypass grafting. The resting pHi is 7.22 ± 0.03 and 7.17 ± 0.02 for HEPES- (nominally HCO₃⁻-free) and CO₂/HCO₃⁻- buffered solution, respectively. In HEPES-buffered solution, a pHi recovery from induced intracellular acidosis could be blocked completely by 30 μM HOE 694 (3-methylsulfonyl-4-piperidinobenzoyl, guanidine hydrochloride) a specific NHE inhibitor, or by removing [Na⁺]₀. In 3% CO₂/HCO₃⁻-buffered solution, HOE 694 slowed the pHi recovery from the induced intracellular acidosis only, while adding together with DIDS (a specific NBC inhibitor) or removal of [Na⁺]₀ entirely inhibited the acid extrusion. Moreover, α-cyano-4-hydroxycinnamate (CHC; a specific blocker of MCT) blocked the lactate-induced pHi changes. In conclusion, we demonstrate, for the first time, that 3 different pHi regulators responsible for acid extruding, i.e. NHE and NBC, and MCT, are functionally co-existed in cultured HRASMCs.

Prospective Assessment of Neurocognition in Future Gulf-deployed and Gulf-nondeployed Military Personnel: A Pilot Study

DTIC Science & Technology

2007-02-01

increased emotional distress but with advantaged simple reactiontime. Unit cohesion buffers the adverse effects of early life events on PTSD prior to...motor speed), and emotional (e.g., mood) behaviors thought to reflect neural integrity. Unresolved issues include whether subjective...including neurobehavioral and emotional functioning, (b) examine the impact of deployment-related stress and environmental exposures on

Electrokinetic remediation prefield test methods

NASA Technical Reports Server (NTRS)

Hodko, Dalibor (Inventor)

2000-01-01

Methods for determining the parameters critical in designing an electrokinetic soil remediation process including electrode well spacing, operating current/voltage, electroosmotic flow rate, electrode well wall design, and amount of buffering or neutralizing solution needed in the electrode wells at operating conditions are disclosed These methods are preferably performed prior to initiating a full scale electrokinetic remediation process in order to obtain efficient remediation of the contaminants.

Optical burst switching for the next generation Optical Internet

NASA Astrophysics Data System (ADS)

Yoo, Myungsik

2000-11-01

In recent years, Internet Protocol (IP) over Wavelength Division Multiplexing (WDM) networks for the next generation Internet (or the so-called Optical Internet) have received enormous attention. There are two main drivers for an Optical Internet. One is the explosion of Internet traffic, which seems to keep growing exponentially. The other driver is the rapid advance in the WDM optical networking technology. In this study, key issues in the optical (WDM) layer will be investigated. As a novel switching paradigm for Optical Internet, Optical Burst Switching (OBS) is discussed. By leveraging the attractive properties of optical communications and at the same time, taking into account its limitations, OBS can combine the best of optical circuit-switching and packet/cell switching. The general concept of JET-based OBS protocol is described, including offset time and delayed reservation. In the next generation Optical Internet, one must address how to support Quality of Service (QoS) at the WDM layer since current IP provides only best effort services. The offset-time- based QoS scheme is proposed as a way of supporting QoS at the WDM layer. Unlike existing QoS schemes, offset- time-based QoS scheme does not mandate the use of buffer to differentiate services. For the bufferless WDM switch, the performance of offset- time-based QoS scheme is evaluated in term of blocking probability. In addition, the extra offset time required for class isolation is quantified and the theoretical bounds on blocking probability are analyzed. The offset-time-based scheme is applied to WDM switch with limited fiber delay line (FDL) buffer. We evaluate the effect of having a FDL buffer on the QoS performance of the offset-time-based scheme in terms of the loss probability and queuing delay of bursts. Finally, in order to dimension the network resources in Optical Internet backbone networks, the performance of the offset-time-based QoS scheme is evaluated for the multi-hop case. In particular, we consider very high performance Backbone Network Service (vBNS) backbone network. Various policies such as drop, retransmission, deflection routing and buffering are considered for performance evaluation. The performance results obtained under these policies are compared to decide the most efficient policy for the WDM backbone network.

The influence of partial timber harvesting in riparian buffers on macroinvertebrate and fish communities in small streams in Minnesota, USA

USGS Publications Warehouse

Chizinski, Christopher J.; Vondracek, Bruce C.; Blinn, Charles R.; Newman, Raymond M.; Atuke, Dickson M.; Fredricks, Keith; Hemstad, Nathaniel A.; Merten, Eric C.; Schlesser, Nicholas

2010-01-01

Relatively few evaluations of aquatic macroinvertebrate and fish communities have been published in peer-reviewed literature detailing the effect of varying residual basal area (RBA) after timber harvesting in riparian buffers. Our analysis investigated the effects of partial harvesting within riparian buffers on aquatic macroinvertebrate and fish communities in small streams from two experiments in northern Minnesota northern hardwood-aspen forests. Each experiment evaluated partial harvesting within riparian buffers. In both experiments, benthic macroinvertebrates and fish were collected 1 year prior to harvest and in each of 3 years after harvest. We observed interannual variation for the macroinvertebrate abundance, diversity and taxon richness in the single-basin study and abundance and diversity in the multiple-basin study, but few effects related to harvest treatments in either study. However, interannual variation was not evident in the fish communities and we detected no significant changes in the stream fish communities associated with partially harvested riparian buffers in either study. This would suggest that timber harvesting in riparian management zones along reaches ≤200 m in length on both sides of the stream that retains RBA ≥ 12.4 ± 1.3 m2 ha−1 or on a single side of the stream that retains RBA ≥ 8.7 ± 1.6 m2 ha−1 may be adequate to protect macroinvertebrate and fish communities in our Minnesota study systems given these specific timber harvesting techniques.

Adherence of Enterohemorrhagic Escherichia coli to Human Epithelial Cells: The Role of Intimin

DTIC Science & Technology

1995-04-28

1994). Contamination of salad vegetables (Abdul-Raouf et al., 1993), raw milk (MacDonald et al., 1988), and unpasteurized apple cider (Besser et...membranes were blocked with 5% nonfat dried milk (Carnation Company, los Angeles, Cali!.) in Tris-buffered saline, pH 7.2 with 0.1% Tween-20 (v/v) (1B5-T...then ove~aid with a 1 :5000 dilution of either horseradish peroxidase-conjugated goat anti-mouse Ig (BMB), donkey anti-rabbit Ig (Amersham), or sheep

Multiprocessor Z-Buffer Architecture for High-Speed, High Complexity Computer Image Generation.

DTIC Science & Technology

1983-12-01

Oversampling 50 17. "Poking Through" Effects 51 18. Sampling Paths 52 19. Triangle Variables 54 20. Intelligent Tiling Algorithm 61 21. Tiler Functional Blocks...64 * 22. HSD Interface 65 23. Tiling Machine Setup 67 24. Tiling Machine 68 25. Tile Accumulate 69 26. A lx$ Sorting Machine 77 27. A 2x8 Sorting...Delay 227 87. Effect of Triangle Size on Tiler Throughput Rates 229 88. Tiling Machine Setup Stage Performance for Oversample Mode 234 89. Tiling

Center for the Evaluation of Biomarkers for the Early Detection of Breast Cancer

DTIC Science & Technology

2009-10-01

Table S1, including mammography (BI-RADS) score and breast density at the last mammogram before diagnosis, lymph node positivity, tumor size, number of...Bibliography 1.& Fletcher RH. Should all people over the age of 50 have regular fecal occult-blood tests? If it works, why not do it? New England Journal...blocked for 15 minutes at room temperature in fluores- cence-activated cell sorting (FACS) buffer (PBS, 0.1% bovine serum albumin (BSA), 0.02% sodium

Modulation of Estrogen-Depurinating DNA Adducts by Sulforaphane for Breast Cancer

DTIC Science & Technology

2014-12-01

adducts. NQO1 reduces CE-3,4- 5 quinones back to catechols and GST catalyzes the conjugation of CE-3,4-quinones with glutathione, whereas COMT ... COMT , GSTA1 and β-actin (Sigma) antibodies were made in blocking solution (5% non-fat dry milk in Tris-buffered saline). The blots were incubated...other genes known to influence E2 metabolism, namely CYP1B1 and COMT , were observed (Figure 4A). These inductions exhibited a dose response, with

Identification of miRNA Signatures Associated with Epithelial Ovarian Cancer Chemoresistance with Further Biological and Functional Validation of Identified Key miRNAs

DTIC Science & Technology

2012-08-01

separated on 12% SDS PAGE gels and transferred to nitrocellulose membranes. After blocking with 5% non- fat milk (Labscientific, Inc) in TBS-Tween buffer... Raw mass spectrometric data were processed and analyzed for variations in the spectral counts of peptides between sample sets and bioinformatics was...accomplished using Ingenuity Pathways Analysis (IPA). Results: The total numbers of proteins and peptides identified are listed in the table

Broad Neutralization of Ebolaviruses via a Fusion Loop Epitope Elicited by Immunization

DTIC Science & Technology

2017-03-31

overnight. After incubation with blocking buffer (BB, 2% non- fat milk , 5% FBS in PBS), the WT or mutant supernatant in five-fold serial dilution in BB was...replication competent rVSV pseudotyped with filovirus GP, which also expressed the reporter protein GFP (rVSV-GP-GFP) (Miller et al., 2012). CA45 potently...for proper protein folding and expression. The epitope mapping identified EBOV GP residues R64 within the N-terminus of GP1 in addition to Y517

Depreciation of bearing blocks of rollers of roller conveyers of rolling mills

NASA Astrophysics Data System (ADS)

Artiukh, Viktor; Belyaev, Michael; Ignatovich, Igor; Miloradova, Nadezda

2017-10-01

Essential increase in functional durability of a node of a roller of the roller conveyer of the rolling mill by the rational choice of parameters of the small-size shock-absorber (buffer adapter) is shown. At the same time dimensions of a node don’t change, costs of reconstruction are small. The possibility of management of loadings in a bearing node without change of technology parameters of the process which is carried out by the rolling mill is confirmed.

Pathological α-synuclein in gastrointestinal tissues from prodromal Parkinson disease patients.

PubMed

Stokholm, Morten Gersel; Danielsen, Erik Hvid; Hamilton-Dutoit, Stephen Jacques; Borghammer, Per

2016-06-01

It has been hypothesized that Lewy pathology initiates in the enteric nervous system years prior to debut of clinical motor symptoms in Parkinson disease patients. This study investigates whether Lewy pathology is present in various gastrointestinal tract tissues from Parkinson disease patients in the prodromal phase. We used the Danish National Pathology Registry to identify archived paraffin-embedded tissue blocks from 57 Parkinson disease patients (98 blocks) and 90 control subjects (98 blocks). We employed 2 different immunohistochemistry techniques visualizing aggregated α-synuclein and phosphorylated α-synuclein. Thirty-nine Parkinson disease patients contributed tissues obtained in the prodromal disease phase, whereas 18 Parkinson disease patients contributed tissues obtained solely after Parkinson diagnosis. Prodromal tissues were obtained on average 7.0 years prior to diagnosis (range = 20 years to 4 months), and postdiagnosis tissue on average 2.8 years after diagnosis (range = 2 days to 18 years). Phosphorylated α-synuclein positivity was seen in 22 of 39 (56%) prodromal Parkinson disease subjects and 30 of 67 (45%) prodromal tissue blocks. These fractions were significantly higher compared to control subjects (p = 0.0001 and p = 0.0032, respectively). In contrast, no significant difference was seen in the positivity rate between prodromal Parkinson disease patients and controls when using the aggregated α-synuclein immunohistochemistry technique. We detected Lewy pathology in the gastrointestinal tract of patients up to 20 years prior to their Parkinson disease diagnosis. These findings are in accordance with a hypothesized prodromal disease phase spanning 10 to 20 years. Ann Neurol 2016;79:940-949. © 2016 American Neurological Association.

A comparative study of the annealing behavior of Cu(In,Ga)(S,Se){sub 2} based solar cells with an indium sulfide buffer layer, partly submitted to wet chemical treatments

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

Hönes, C., E-mail: christian.hoenes@de.bosch.com; Laboratory for Photovoltaics, University of Luxembourg, 41 rue du Brill, L-4422 Belvaux; Hackenberg, J.

2015-03-07

Indium sulfide thin films deposited via thermal evaporation from compound source material have been successfully utilized as a cadmium free buffer layer for Cu(In,Ga)Se{sub 2} based solar cells. However, high efficiencies are only reached after an additional annealing step. In this work, the annealing behavior of Cu(In,Ga)(S,Se){sub 2} based indium sulfide buffered solar cells is compared to the annealing behavior of similar cells, which were submitted to wet chemical treatments partly containing cadmium ions. Upon annealing a significant improvement of the initial solar cell characteristics is observed for the untreated cell and is related to the increase of activation energymore » for the carrier recombination process and a decrease of the ideality factor within the one diode model. It is shown here that this improvement can also be achieved by wet treatments of the absorber prior to buffer layer deposition. Upon annealing these treated cells still gain in collection length but lose open circuit voltage, which is explained here within a model including a highly p-doped absorber surface layer and supported by simulations showing that a decrease in doping density of such a surface layer would lead to the observed effects.« less

Vermiculite's strong buffer capacity renders it unsuitable for studies of acidity on soybean (Glycine max L.) nodulation and growth.

PubMed

Indrasumunar, Arief; Gresshoff, Peter M

2013-11-14

Vermiculite is the most common soil-free growing substrate used for plants in horticultural and scientific studies due to its high water holding capacity. However, some studies are not suitable to be conducted in it. The described experiments aimed to test the suitability of vermiculite to study the effect of acidity on nodulation and growth of soybean (Glycine max L.). Two different nutrient solutions (Broughton & Dilworth, and modified Herridge nutrient solutions) with or without MES buffer addition were used to irrigate soybean grown on vermiculite growth substrates. The pH of nutrient solutions was adjusted to either pH 4.0 or 7.0 prior its use. The nodulation and vegetative growth of soybean plants were assessed at 3 and 4 weeks after inoculation. The unsuitability of presumably inert vermiculite as a physical plant growth substrate for studying the effects of acidity on soybean nodulation and plant growth was illustrated. Nodulation and growth of soybean grown in vermiculite were not affected by irrigation with pH-adjusted nutrient solution either at pH 4.0 or 7.0. This was reasonably caused by the ability of vermiculite to neutralise (buffer) the pH of the supplied nutrient solution (pH 2.0-7.0). Due to its buffering capacity, vermiculite cannot be used as growth support to study the effect of acidity on nodulation and plant growth.

An incremental database access method for autonomous interoperable databases

NASA Technical Reports Server (NTRS)

Roussopoulos, Nicholas; Sellis, Timos

1994-01-01

We investigated a number of design and performance issues of interoperable database management systems (DBMS's). The major results of our investigation were obtained in the areas of client-server database architectures for heterogeneous DBMS's, incremental computation models, buffer management techniques, and query optimization. We finished a prototype of an advanced client-server workstation-based DBMS which allows access to multiple heterogeneous commercial DBMS's. Experiments and simulations were then run to compare its performance with the standard client-server architectures. The focus of this research was on adaptive optimization methods of heterogeneous database systems. Adaptive buffer management accounts for the random and object-oriented access methods for which no known characterization of the access patterns exists. Adaptive query optimization means that value distributions and selectives, which play the most significant role in query plan evaluation, are continuously refined to reflect the actual values as opposed to static ones that are computed off-line. Query feedback is a concept that was first introduced to the literature by our group. We employed query feedback for both adaptive buffer management and for computing value distributions and selectivities. For adaptive buffer management, we use the page faults of prior executions to achieve more 'informed' management decisions. For the estimation of the distributions of the selectivities, we use curve-fitting techniques, such as least squares and splines, for regressing on these values.

Spontaneously self-assembled micelles from poly(ethylene glycol)-b-poly(epsilon-caprolactone-co-trimethylene carbonate) for drug solubilization.

PubMed

Latere, Dwan'Isa J P; Rouxhet, L; Brewster, M E; Préat, V; Ariën, A

2008-03-01

Di-block copolymers composed of polyethylene glycol (PEG) and a second block of (co)polyesters of epsilon-caprolactone (CL) and/or trimethylene carbonate (TMC) were synthesized and characterized. Tin octoate was used as catalyst and polymerization were completed over a period of 24 h with high conversion (> 95%). Self-assembling properties in water were evaluated. All di-block copolymers behave similarly except when PCL served as the second block. Stable crew-cut micelles of about 20 nm were obtained by direct dissolution of the liquid di-block copolymers in water at room temperature. When PCL was present as the second block, no solubilization occurred. Drug encapsulation of poorly water-soluble drugs belonging to biopharmaceutics classification system (BCS) class II (ketoprofen and furosemide) was evaluated. Experimental solubility for these two drugs shows a significant enhancement such that a maximum value of 23.4 mg/ml was obtained for ketoprofen in a 10% w/v micellar solution as compared to 0.14 mg in water. In the case of furosemide, the solubility increased from 0.04 mg/ml in water to about 3.2 mg/ml in a 10% w/v micellar solution. Enzymatic degradation of diblock copolymers was also studied in the presence of Pseudomonas lipase in a phosphate buffer solution (pH 7.4). Results indicated rapid degradation of copolymers containing relatively higher amounts of CL compared to TMC suggesting the potential in vivo degradation.

Fundamental properties of local anesthetics: half-maximal blocking concentrations for tonic block of Na+ and K+ channels in peripheral nerve.

PubMed

Bräu, M E; Vogel, W; Hempelmann, G

1998-10-01

Local anesthetics suppress excitability by interfering with ion channel function. Ensheathment of peripheral nerve fibers, however, impedes diffusion of drugs to the ion channels and may influence the evaluation of local anesthetic potencies. Investigating ion channels in excised membrane patches avoids these diffusion barriers. We investigated the effect of local anesthetics with voltage-dependent Na+ and K+ channels in enzymatically dissociated sciatic nerve fibers of Xenopus laevis using the patch clamp method. The outside-out configuration was chosen to apply drugs to the external face of the membrane. Local anesthetics reversibly blocked the transient Na+ inward current, as well as the steady-state K+ outward current. Half-maximal tonic inhibiting concentrations (IC50), as obtained from concentration-effect curves for Na+ current block were: tetracaine 0.7 microM, etidocaine 18 microM, bupivacaine 27 microM, procaine 60 microM, mepivacaine 149 microM, and lidocaine 204 microM. The values for voltage-dependent K+ current block were: bupivacaine 92 microM, etidocaine 176 microM, tetracaine 946 microM, lidocaine 1118 microM, mepivacaine 2305 microM, and procaine 6302 microM. Correlation of potencies with octanol:buffer partition coefficients (logP0) revealed that ester-bound local anesthetics were more potent in blocking Na+ channels than amide drugs. Within these groups, lipophilicity governed local anesthetic potency. We conclude that local anesthetic action on peripheral nerve ion channels is mediated via lipophilic drug-channel interactions. Half-maximal blocking concentrations of commonly used local anesthetics for Na+ and K+ channel block were determined on small membrane patches of peripheral nerve fibers. Because drugs can directly diffuse to the ion channel in this model, these data result from direct interactions of the drugs with ion channels.

The Combination of RSA And Block Chiper Algorithms To Maintain Message Authentication

NASA Astrophysics Data System (ADS)

Yanti Tarigan, Sepri; Sartika Ginting, Dewi; Lumban Gaol, Melva; Lorensi Sitompul, Kristin

2017-12-01

RSA algorithm is public key algorithm using prime number and even still used today. The strength of this algorithm lies in the exponential process, and the factorial number into 2 prime numbers which until now difficult to do factoring. The RSA scheme itself adopts the block cipher scheme, where prior to encryption, the existing plaintext is divide in several block of the same length, where the plaintext and ciphertext are integers between 1 to n, where n is typically 1024 bit, and the block length itself is smaller or equal to log(n)+1 with base 2. With the combination of RSA algorithm and block chiper it is expected that the authentication of plaintext is secure. The secured message will be encrypted with RSA algorithm first and will be encrypted again using block chiper. And conversely, the chipertext will be decrypted with the block chiper first and decrypted again with the RSA algorithm. This paper suggests a combination of RSA algorithms and block chiper to secure data.

50 CFR 216.254 - Mitigation.

Code of Federal Regulations, 2010 CFR

2010-10-01

... safety for marine mammals with a radius of no less than 5 nm (9.3 km) for single bombs and 10 nm (18.5 km) for double bombs and a buffer zone from the outer edge of the safety zone with a radius of at least 2.5 nm (4.6 km) for single bombs and 5 nm (18.5 km) for double bombs. (b) Prior to a JASSM or SDB...

EnviroAtlas - Phoenix, AZ - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. Forest is defined as Trees & Forest. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health effects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

EnviroAtlas - Pittsburgh, PA - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. Forest is defined as Trees & Forest. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health effects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

The fabrication of white light-emitting diodes using the n-ZnO/NiO/p-GaN heterojunction with enhanced luminescence.

PubMed

Abbasi, Mazhar Ali; Ibupoto, Zafar Hussain; Hussain, Mushtaque; Nur, Omer; Willander, Magnus

2013-07-13

Cheap and efficient white light-emitting diodes (LEDs) are of great interest due to the energy crisis all over the world. Herein, we have developed heterojunction LEDs based on the well-aligned ZnO nanorods and nanotubes on the p-type GaN with the insertion of the NiO buffer layer that showed enhancement in the light emission. Scanning electron microscopy have well demonstrated the arrays of the ZnO nanorods and the proper etching into the nanotubes. X-ray diffraction study describes the wurtzite crystal structure array of ZnO nanorods with the involvement of GaN at the (002) peak. The cathodoluminescence spectra represent strong and broad visible emission peaks compared to the UV emission and a weak peak at 425 nm which is originated from GaN. Electroluminescence study has shown highly improved luminescence response for the LEDs fabricated with NiO buffer layer compared to that without NiO layer. Introducing a sandwich-thin layer of NiO between the n-type ZnO and the p-type GaN will possibly block the injection of electrons from the ZnO to the GaN. Moreover, the presence of NiO buffer layer might create the confinement effect.

Thickness effect of Gd2Zr2O7 buffer layer on performance of YBa2Cu3O7-δ coated conductors

NASA Astrophysics Data System (ADS)

Qiu, Wenbin; Fan, Feng; Lu, Yuming; Liu, Zhiyong; Bai, Chuanyi; Guo, Yanqun; Cai, Chuanbing

2014-12-01

Bilayer buffer architecture of Gd2Zr2O7 (GZO)/Y2O3 was prepared on the biaxially textured tape of Ni-5 at% W (NiW) by reactive sputtering deposition technique. The buffer layer of GZO films were deposited with different thicknesses on Y2O3 seeding layer with a given thickness of 20 nm. According to the results of φ-scan, the in-plane FWHMs of GZO films decreased and then reversed with increasing thickness of GZO, which corresponded with the in-plane FWHMs and superconducting properties of YBa2Cu3O7-δ (YBCO) films. Reflection High-Energy Electron Diffraction (RHEED) was carried out to examine the surface texture of GZO films and the deteriorated surface alignment was found for thicker films. The thickness effect of GZO on performance of YBCO is the coupling result of surface texture and blocking effect caused by thickness. With the balance of these two factors, the YBCO/GZO(120 nm)/Y2O3/NiW architecture exhibit relatively high performance with the transition temperature Tc of 92 K, a transition width ΔTc below 1 K, and a critical current density Jc of 0.65 MA/cm2.

EnviroAtlas - Austin, TX - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. Forest is defined as Trees & Forest. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health affects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

EnviroAtlas - Woodbine, IA - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. Forest is defined as Trees & Forest. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health effects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

EnviroAtlas - Paterson, NJ - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. Forest is defined as Trees & Forest. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health effects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

EnviroAtlas - Milwaukee, WI - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. Forest is defined as Trees & Forest and Woody Wetlands. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health effects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

EnviroAtlas - Portland, OR - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. Forest is defined as Trees & Forest and Woody Wetlands. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health effects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (http:/www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

EnviroAtlas - Memphis, TN - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. Forest is defined as Trees & Forest and Woody Wetlands. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health effects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

EnviroAtlas - Fresno, CA - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. Forest is defined as Trees & Forest and Orchards. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health effects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

EnviroAtlas - Tampa, FL - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. Forest is defined as Trees & Forest and Woody Wetlands. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health effects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

EnviroAtlas - New Bedford, MA - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. Forest is defined as Trees & Forest and Woody Wetlands. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health effects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

EnviroAtlas - Minneapolis/St. Paul, MN - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. In this community, forest is defined as Trees and Forest and Woody Wetlands. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health affects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

EnviroAtlas - Green Bay, WI - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. Forest is defined as Trees & Forest and Woody Wetlands. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health effects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets ).

EnviroAtlas - Cleveland, OH - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. In this community, forest is defined as Trees & Forest and Woody Wetlands. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health affects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas ) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

EnviroAtlas - Des Moines, IA - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. Forest is defined as Trees & Forest. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health effects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://enviroatlas.epa.gov/EnviroAtlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

EnviroAtlas - Durham, NC - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. Forest is defined as Trees & Forest. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health effects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas ) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets ).

EnviroAtlas - New York, NY - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. In this community, forest is defined as Trees & Forest. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health effects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

EnviroAtlas - Portland, ME - Near Road Block Group Summary

EPA Pesticide Factsheets

This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas community boundary. Forest is defined as Trees & Forest and Woody Wetlands. Sufficient tree bufferage is defined as 25% coverage within the circular moving window with a radius of 14.5m at any given point along the roadway. There are potential negative health effects for those living in a location without a sufficient tree buffer. Those populations are estimated here using dasymetric data calculated for the EnviroAtlas. There are potential negative health effects for those living in a location without a sufficient tree buffer. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

Ammonia triggers neuronal disinhibition and seizures by impairing astrocyte potassium buffering

PubMed Central

Thrane, Vinita Rangroo; Thrane, Alexander S; Wang, Fushun; Cotrina, Maria L; Smith, Nathan A; Chen, Michael; Xu, Qiwu; Kang, Ning; Fujita, Takumi; Nagelhus, Erlend A; Nedergaard, Maiken

2013-01-01

Ammonia is a ubiquitous waste product of protein metabolism that can accumulate in numerous metabolic disorders, causing neurological dysfunction ranging from cognitive impairment to tremor, ataxia, seizures, coma and death1. The brain is especially vulnerable to ammonia as it readily crosses the blood-brain barrier in its gaseous form, NH3, and rapidly saturates its principal removal pathway located in astrocytes2. Thus, we wanted to determine how astrocytes contribute to the initial deterioration of neurological functions characteristic of hyperammonemia in vivo. Using a combination of two-photon imaging and electrophysiology in awake head-restrained mice, we show that ammonia rapidly compromises astrocyte potassium buffering, increasing extracellular potassium concentration and overactivating the Na+-K+-2Cl− cotransporter isoform 1 (NKCC1) in neurons. The consequent depolarization of the neuronal GABA reversal potential (EGABA) selectively impairs cortical inhibitory networks. Genetic deletion of NKCC1 or inhibition of it with the clinically used diuretic bumetanide potently suppresses ammonia-induced neurological dysfunction. We did not observe astrocyte swelling or brain edema in the acute phase, calling into question current concepts regarding the neurotoxic effects of ammonia3,4. Instead, our findings identify failure of potassium buffering in astrocytes as a crucial mechanism in ammonia neurotoxicity and demonstrate the therapeutic potential of blocking this pathway by inhibiting NKCC1. PMID:24240184

Response of subterranean termites (Isoptera:Rhinotermitidae) to stressed nestmates

Treesearch

T.G. Shelton; J.K. Grace; R.J. Woodrow; R.J. Oshiro

2011-01-01

Reticulitermes flavipes (Kollar), R. virginicus Banks, and Coptotermes formosanus Shiraki were stressed by holding them at 25°C or 28°C, respectively, in metal pans for 5 d prior to introduction into 1 side of 3-jar arenas (3 containers connected serially) containing freshlycollected nestmates. After 14 d, mass loss of wooden blocks was determined for blocks from the...

A discrete event simulation model of clinical and operating room efficiency outcomes of sugammadex versus neostigmine for neuromuscular block reversal in Canada.

PubMed

Insinga, Ralph P; Joyal, Cédric; Goyette, Alexandra; Galarneau, André

2016-11-16

The objective of this analysis is to explore potential impact on operating room (OR) efficiency and incidence of residual neuromuscular blockade (RNMB) with use of sugammadex (Bridion™, Merck & Co., Inc., Kenilworth, NJ USA) versus neostigmine for neuromuscular block reversal in Canada. A discrete event simulation (DES) model was developed to compare ORs using either neostigmine or sugammadex for NMB reversal over one month. Selected inputs included OR procedure and turnover times, hospital policies for paid staff overtime and procedural cancellations due to OR time over-run, and reductions in RNMB and associated complications with sugammadex use. Trials show sugammadex's impact on OR time and RNMB varies by whether full neuromuscular recovery (train-of-four ratio ≥0.9) is verified prior to extubation in the OR. Scenarios were therefore evaluated reflecting varied assumptions for neuromuscular reversal practices. With use of moderate neuromuscular block, when full neuromuscular recovery is verified prior to extubation (93 procedures performed with sugammadex, 91 with neostigmine), use of sugammadex versus neostigmine avoided 2.4 procedural cancellations due to OR time over-run and 33.5 h of paid staff overtime, while saving an average of 62 min per OR day. No difference was observed between comparators for these endpoints in the scenario when full neuromuscular recovery was not verified prior to extubation, however, per procedure risk of RNMB at extubation was reduced from 60% to 4% (reflecting 51 cases prevented), with associated reductions in risks of hypoxemia (12 cases avoided) and upper airway obstruction (23 cases avoided). Sugammadex impact in reversing deep neuromuscular block was evaluated in an exploratory analysis. When it was hypothetically assumed that 30 min of OR time were saved per procedure, the number of paid hours of staff over-time dropped from 84.1 to 32.0, with a 93% reduction in the per patient risk of residual blockade. In clinical practice within Canada, for the majority of patients currently managed with moderate neuromuscular block, the principal impact of substituting sugammadex for neostigmine is likely to be a reduction in the risk of residual blockade and associated complications. For patients maintained at a deep level of block to the end of the procedure, sugammadex is likely to both enhance OR efficiency and reduce residual block complications.

Chimeric Plastics : a new class of thermoplastic

NASA Astrophysics Data System (ADS)

Sonnenschein, Mark

A new class of thermoplastics (dubbed ``Chimerics'') is described that exhibits a high temperature glass transition followed by high performance elastomer properties, prior to melting. These transparent materials are comprised of co-continuous phase-separated block copolymers. One block is an amorphous glass with a high glass transition temperature, and the second is a higher temperature phase transition block creating virtual thermoreversible crosslinks. The material properties are highly influenced by phase separation on the order of 10-30 nanometers. At lower temperatures the polymer reflects the sum of the block copolymer properties. As the amorphous phase glass transition is exceeded, the virtual crosslinks of the higher temperature second phase dominate the plastic properties, resulting in rubber-like elasticity.

Glial Control of Endocannabinoid Heterosynaptic Modulation in Hypothalamic Magnocellular Neuroendocrine Cells

PubMed Central

Popescu, Ion R.

2013-01-01

Cannabinoid receptors are functionally operant at both glutamate and GABA synapses on hypothalamic magnocellular neuroendocrine cells; however, retrograde endocannabinoid actions are evoked at only glutamate synapses. We tested whether the functional targeting of evoked retrograde endocannabinoid actions to glutamate, and not GABA, synapses on magnocellular neurons is the result of the spatial restriction of extracellular endocannabinoids by astrocytes. Whole-cell GABA synaptic currents were recorded in magnocellular neurons in rat hypothalamic slices following manipulations to reduce glial buffering of extracellular signals. Depolarization- and glucocorticoid-evoked retrograde endocannabinoid suppression of synaptic GABA release was not detected under normal conditions, but occurred in both oxytocin and vasopressin neurons under conditions of attenuated glial coverage and depressed glial metabolic function, suggesting an emergent endocannabinoid modulation of GABA synapses with the loss of astrocyte function. Tonic endocannabinoid suppression of GABA release was insensitive to glial manipulation. Blocking cannabinoid transport mimicked, and increasing the extracellular viscosity reversed, the effect of suppressed glial buffering on the endocannabinoid modulation of GABA release. Evoked, but not tonic, endocannabinoid modulation of GABA synapses was mediated by 2-arachidonoylglycerol. Therefore, depolarization- and glucocorticoid-evoked 2-arachidonoylglycerol release from magnocellular neurons is spatially restricted to glutamate synapses by astrocytes, but spills over onto GABA synapses under conditions of reduced astrocyte buffering; tonic endocannabinoid modulation of GABA release, in contrast, is likely mediated by anandamide and is insensitive to astrocytic buffering. Astrocytes, therefore, provide dynamic control of stimulus-evoked 2-arachidonoylglycerol, but not tonic anandamide, regulation of GABA synaptic inputs to magnocellular neuroendocrine cells under different physiological conditions. PMID:24227742

A PFM-based MWIR DROIC employing off-pixel fine conversion of photocharge to digital using integrated column ADCs

NASA Astrophysics Data System (ADS)

Abbasi, S.; Galioglu, A.; Shafique, A.; Ceylan, O.; Yazici, M.; Gurbuz, Y.

2017-02-01

A 32x32 prototype of a digital readout IC (DROIC) for medium-wave infrared focal plane arrays (MWIR IR-FPAs) is presented. The DROIC employs in-pixel photocurrent to digital conversion based on a pulse frequency modulation (PFM) loop and boasts a novel feature of off-pixel residue conversion using 10-bit column SAR ADCs. The remaining charge at the end of integration in typical PFM based digital pixel sensors is usually wasted. Previous works employing in-pixel extended counting methods make use of extra memory and counters to convert this left-over charge to digital, thereby performing fine conversion of the incident photocurrent. This results in a low quantization noise and hence keeps the readout noise low. However, focal plane arrays (FPAs) with small pixel pitch are constrained in pixel area, which makes it difficult to benefit from in-pixel extended counting circuitry. Thus, in this work, a novel approach to measure the residue outside the pixel using column -parallel SAR ADCs has been proposed. Moreover, a modified version of the conventional PFM based pixel has been designed to help hold the residue charge and buffer it to the column ADC. In addition to the 2D array of pixels, the prototype consists of 32 SAR ADCs, a timing controller block and a memory block to buffer the residue data coming out of the ADCs. The prototype has been designed and fabricated in 90nm CMOS.

Autonomous Distributed Congestion Control Scheme in WCDMA Network

NASA Astrophysics Data System (ADS)

Ahmad, Hafiz Farooq; Suguri, Hiroki; Choudhary, Muhammad Qaisar; Hassan, Ammar; Liaqat, Ali; Khan, Muhammad Umer

Wireless technology has become widely popular and an important means of communication. A key issue in delivering wireless services is the problem of congestion which has an adverse impact on the Quality of Service (QoS), especially timeliness. Although a lot of work has been done in the context of RRM (Radio Resource Management), the deliverance of quality service to the end user still remains a challenge. Therefore there is need for a system that provides real-time services to the users through high assurance. We propose an intelligent agent-based approach to guarantee a predefined Service Level Agreement (SLA) with heterogeneous user requirements for appropriate bandwidth allocation in QoS sensitive cellular networks. The proposed system architecture exploits Case Based Reasoning (CBR) technique to handle RRM process of congestion management. The system accomplishes predefined SLA through the use of Retrieval and Adaptation Algorithm based on CBR case library. The proposed intelligent agent architecture gives autonomy to Radio Network Controller (RNC) or Base Station (BS) in accepting, rejecting or buffering a connection request to manage system bandwidth. Instead of simply blocking the connection request as congestion hits the system, different buffering durations are allocated to diverse classes of users based on their SLA. This increases the opportunity of connection establishment and reduces the call blocking rate extensively in changing environment. We carry out simulation of the proposed system that verifies efficient performance for congestion handling. The results also show built-in dynamism of our system to cater for variety of SLA requirements.

Effect of Alloy 625 Buffer Layer on Hardfacing of Modified 9Cr-1Mo Steel Using Nickel Base Hardfacing Alloy

NASA Astrophysics Data System (ADS)

Chakraborty, Gopa; Das, C. R.; Albert, S. K.; Bhaduri, A. K.; Murugesan, S.; Dasgupta, Arup

2016-04-01

Dashpot piston, made up of modified 9Cr-1Mo steel, is a part of diverse safety rod used for safe shutdown of a nuclear reactor. This component was hardfaced using nickel base AWS ER NiCr-B alloy and extensive cracking was experienced during direct deposition of this alloy on dashpot piston. Cracking reduced considerably and the component was successfully hardfaced by application of Inconel 625 as buffer layer prior to hardface deposition. Hence, a separate study was undertaken to investigate the role of buffer layer in reducing the cracking and on the microstructure of the hardfaced deposit. Results indicate that in the direct deposition of hardfacing alloy on modified 9Cr-1Mo steel, both heat-affected zone (HAZ) formed and the deposit layer are hard making the thickness of the hard layer formed equal to combined thickness of both HAZ and deposit. This hard layer is unable to absorb thermal stresses resulting in the cracking of the deposit. By providing a buffer layer of Alloy 625 followed by a post-weld heat treatment, HAZ formed in the modified 9Cr-1Mo steel is effectively tempered, and HAZ formed during the subsequent deposition of the hardfacing alloy over the Alloy 625 buffer layer is almost completely confined to Alloy 625, which does not harden. This reduces the cracking susceptibility of the deposit. Further, unlike in the case of direct deposition on modified 9Cr-1Mo steel, dilution of the deposit by Ni-base buffer layer does not alter the hardness of the deposit and desired hardness on the deposit surface could be achieved even with lower thickness of the deposit. This gives an option for reducing the recommended thickness of the deposit, which can also reduce the risk of cracking.

Growth and Characterization of (211)B Cadmium Telluride Buffer Layer Grown by Metal-organic Vapor Phase Epitaxy on Nanopatterned Silicon for Mercury Cadmium Telluride Based Infrared Detector Applications

NASA Astrophysics Data System (ADS)

Shintri, Shashidhar S.

Mercury cadmium telluride (MCT or Hg1-xCdxTe) grown by molecular beam epitaxy (MBE) is presently the material of choice for fabricating infrared (IR) detectors used in night vision based military applications. The focus of MCT epitaxy has gradually shifted since the last decade to using Si as the starting substrate since it offers several advantages. But the ˜19 % lattice mismatch between MCT and Si generates lots of crystal defects some of which degrade the performance of MCT devices. Hence thick CdTe films are used as buffer layers on Si to accommodate the defects. However, growth of high quality single crystal CdTe on Si is challenging and to date, the best MBE CdTe/Si reportedly has defects in the mid-105 cm -2 range. There is a critical need to reduce the defect levels by at least another order of magnitude, which is the main motivation behind the present work. The use of alternate growth technique called metal-organic vapor phase epitaxy (MOVPE) offers some advantages over MBE and in this work MOVPE has been employed to grow the various epitaxial films. In the first part of this work, conditions for obtaining high quality (211)B CdTe epitaxy on (211)Si were achieved, which also involved studying the effect of having additional intermediate buffer layers such as Ge and ZnTe and incorporation of in-situ thermal cyclic annealing (TCA) to reduce the dislocation density. A critical problem of Si cross-contamination due to 'memory effect' of different reactant species was minimized by introducing tertiarybutylArsine (TBAs) which resulted in As-passivation of (211)Si. The best 8-10 µm thick CdTe films on blanket (non-patterned) Si had dislocations around 3×105 cm-2, which are the best reported by MOVPE till date and comparable to the highest quality films available by MBE. In the second part of the work, nanopatterned (211)Si was used to study the effect of patterning on the crystal quality of epitaxial CdTe. In one such study, patterning of ˜20 nm holes in SiO2/Ge/(211)Si was achieved by block co-polymer (BCP) lithography. Conditions for selective CdTe epitaxy was achieved and results showed different defect propagation mechanism at the patterned interface compared to the films grown on blanket Si. In another study, patterning of ˜360 nm holes in SiO2/(211)Si was done by molecular transfer lithography (MxL). Conditions for selective Ge and CdTe epitaxy were achieved which was the most challenging part of this work. Thin CdTe films were characterized to check the effect of nanopatterning. Certain results invariably showed that CdTe grown on nanopatterned substrates demonstrated promise of defect reduction and blocking close to the growth interface. But presently, nanopatterning also offers some serious challenges such as uniformity of patterns and substrate cleaning prior to growth for successful implementation of epitaxy on very large areas. Such factors resulted in degradation of overall crystal quality and will be discussed in this work. This is the first successful demonstration of selective (211)B CdTe epitaxy on Si by MOVPE using some of the relatively novel and promising nanopatterning techniques.

Focusing Light Beams To Improve Atomic-Vapor Optical Buffers

NASA Technical Reports Server (NTRS)

Strekalov, Dmitry; Matsko, Andrey; Savchenkov, Anatoliy

2010-01-01

Specially designed focusing of light beams has been proposed as a means of improving the performances of optical buffers based on cells containing hot atomic vapors (e.g., rubidium vapor). There is also a companion proposal to improve performance by use of incoherent optical pumping under suitable conditions. Regarding the proposal to use focusing: The utility of atomic-vapor optical buffers as optical storage and processing devices has been severely limited by nonuniform spatial distributions of intensity in optical beams, arising from absorption of the beams as they propagate in atomic-vapor cells. Such nonuniformity makes it impossible to optimize the physical conditions throughout a cell, thereby making it impossible to optimize the performance of the cell as an optical buffer. In practical terms simplified for the sake of brevity, "to optimize" as used here means to design the cell so as to maximize the group delay of an optical pulse while keeping the absorption and distortion of the pulse reasonably small. Regarding the proposal to use incoherent optical pumping: For reasons too complex to describe here, residual absorption of light is one of the main impediments to achievement of desirably long group delays in hot atomic vapors. The present proposal is directed toward suppressing residual absorption of light. The idea of improving the performance of slow-light optical buffers by use of incoherent pumping overlaps somewhat with the basic idea of Raman-based slow-light systems. However, prior studies of those systems did not quantitatively answer the question of whether the performance of an atomic vapor or other medium that exhibits electromagnetically induced transparency (EIT) with Raman gain is superior to that of a medium that exhibits EIT without Raman gain.

Preoperative Angiotensin Blocking Drug Therapy Is not Associated with Atrial Fibrillation after Cardiac Surgery

PubMed Central

Rader, Florian; Van Wagoner, David R.; Gillinov, A. Marc; Blackstone, Eugene H.

2010-01-01

Background Preoperative use of angiotensin blocking drug therapy (ABDT) with ACE-inhibitors or Angiotensin II receptor blockers (ARBs) and its link to occurrence of postoperative atrial fibrillation (POAF), a common marker of poor outcomes after cardiac surgery, remains controversial. Methods From 1997-2003 10,552 patients underwent coronary artery bypass grafting (CABG) with or without valve surgery. To adjust for differences of clinical characteristics between patients receiving ABDT within 24 hours prior to surgery compared to those who did not, propensity score analyses were conducted. Results ABDT was prescribed in 4,795 (45%) prior to surgery of which 1,725 (36%) developed POAF prior to discharge vs. 1908 (33%) of 5,757 patients who have not received ABDT (unadjusted odds ratio [OR] of 1.13 (95% Confidence Interval [CI] 1.05-1.25, p<0.01). In 6744 propensity score matched patients with well balanced co-morbidity profiles, ABDT was not associated with POAF (OR 1.05, CI 0.95-1.16, p=0.38). Stratified analysis within quintiles of propensity score and propensity-adjusted logistic multivariable regression confirmed these findings. Conclusions In this large observational study we found no evidence of an association between preoperative angiotensin blockade and the occurrence of postoperative atrial fibrillation. Adequately powered randomized studies are needed to clarify the best strategy of perioperative angiotensin blocking drug therapy in patients with and without guideline-based indications. PMID:20691840

Method for solidification of radioactive and other hazardous waste

DOEpatents

Anshits, Alexander G.; Vereshchagina, Tatiana A.; Voskresenskaya, Elena N.; Kostin, Eduard M.; Pavlov, Vyacheslav F.; Revenko, Yurii A.; Tretyakov, Alexander A.; Sharonova, Olga M.; Aloy, Albert S.; Sapozhnikova, Natalia V.; Knecht, Dieter A.; Tranter, Troy J.; Macheret, Yevgeny

2002-01-01

Solidification of liquid radioactive waste, and other hazardous wastes, is accomplished by the method of the invention by incorporating the waste into a porous glass crystalline molded block. The porous block is first loaded with the liquid waste and then dehydrated and exposed to thermal treatment at 50-1,000.degree. C. The porous glass crystalline molded block consists of glass crystalline hollow microspheres separated from fly ash (cenospheres), resulting from incineration of fossil plant coals. In a preferred embodiment, the porous glass crystalline blocks are formed from perforated cenospheres of grain size -400+50, wherein the selected cenospheres are consolidated into the porous molded block with a binder, such as liquid silicate glass. The porous blocks are then subjected to repeated cycles of saturating with liquid waste, and drying, and after the last cycle the blocks are subjected to calcination to transform the dried salts to more stable oxides. Radioactive liquid waste can be further stabilized in the porous blocks by coating the internal surface of the block with metal oxides prior to adding the liquid waste, and by coating the outside of the block with a low-melting glass or a ceramic after the waste is loaded into the block.

Protein precipitation of diluted samples in SDS-containing buffer with acetone leads to higher protein recovery and reproducibility in comparison with TCA/acetone approach.

PubMed

Santa, Cátia; Anjo, Sandra I; Manadas, Bruno

2016-07-01

Proteomic approaches are extremely valuable in many fields of research, where mass spectrometry methods have gained an increasing interest, especially because of the ability to perform quantitative analysis. Nonetheless, sample preparation prior to mass spectrometry analysis is of the utmost importance. In this work, two protein precipitation approaches, widely used for cleaning and concentrating protein samples, were tested and compared in very diluted samples solubilized in a strong buffer (containing SDS). The amount of protein recovered after acetone and TCA/acetone precipitation was assessed, as well as the protein identification and relative quantification by SWATH-MS yields were compared with the results from the same sample without precipitation. From this study, it was possible to conclude that in the case of diluted samples in denaturing buffers, the use of cold acetone as precipitation protocol is more favourable than the use of TCA/acetone in terms of reproducibility in protein recovery and number of identified and quantified proteins. Furthermore, the reproducibility in relative quantification of the proteins is even higher in samples precipitated with acetone compared with the original sample. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

An optimized method for elution of enteroviral RNA from a cellulose-based substrate.

PubMed

Li, Yan; Yoshida, Hiromu; Wang, Lu; Tao, Zexin; Wang, Haiyan; Lin, Xiaojuan; Xu, Aiqiang

2012-12-01

The Flinders Technology Australia (FTA) Elute Card is a commercial product that facilitates the collection, transport, archiving and processing of nucleic acids from a wide variety of biological samples at room temperature. While the cards have been designed so that sterile/deionized water can elute DNA easily, they are not suitable for some less stable RNAs. This study was undertaken to determine the optimal conditions such as the buffer type, buffer pH and incubation temperature for the elution of enteroviral RNA from FTA Elute Cards prior to quantitative analysis using real-time PCR (qPCR) or consensus degenerate hybrid oligonucleotide primer VP1 RT-semi nested PCR (CODEHOP VP1 RT-snPCR). TE-1 (pH 8.0), rather than sterile water, was the best buffer for high efficiency elution of enteroviral RNA at 95°C. However, as the estimated recovery rate of viral RNA eluted from the cards averaged to be only 6.1%, enterovirus assays using FTA elution should be considered qualitative, especially at low virus titers, and therefore the results of the assay should be interpreted carefully. Copyright © 2012 Elsevier B.V. All rights reserved.

A method for landscape analysis of forestry guidelines using bird habitat models and the Habplan harvest scheduler

USGS Publications Warehouse

Loehle, C.; Van Deusen, P.; Wigley, T.B.; Mitchell, M.S.; Rutzmoser, S.H.; Aggett, J.; Beebe, J.A.; Smith, M.L.

2006-01-01

Wildlife-habitat relationship models have sometimes been linked with forest simulators to aid in evaluating outcomes of forest management alternatives. However, linking wildlife-habitat models with harvest scheduling software would provide a more direct method for assessing economic and ecological implications of alternative harvest schedules in commercial forest operations. We demonstrate an approach for frontier analyses of wildlife benefits using the Habplan harvest scheduler and spatially explicit wildlife response models in the context of operational forest planning. We used the Habplan harvest scheduler to plan commercial forest management over a 40-year horizon at a landscape scale under five scenarios: unmanaged, an unlimited block-size option both with and without riparian buffers, three cases with different block-size restrictions, and a set-asides scenario in which older stands were withheld from cutting. The potential benefit to wildlife was projected based on spatial models of bird guild richness and species probability of detection. Harvested wood volume provided a measure of scenario costs, which provides an indication of management feasibility. Of nine species and guilds, none appeared to benefit from 50 m riparian buffers, response to an unmanaged scenario was mixed and expensive, and block-size restrictions (maximum harvest unit size) provided no apparent benefit and in some cases were possibly detrimental to bird richness. A set-aside regime, however, appeared to provide significant benefits to all species and groups, probably through increased landscape heterogeneity and increased availability of older forest. Our approach shows promise for evaluating costs and benefits of forest management guidelines in commercial forest enterprises and improves upon the state of the art by utilizing an optimizing harvest scheduler as in commercial forest management, multiple measures of biodiversity (models for multiple species and guilds), and spatially explicit wildlife response models. ?? 2006 Elsevier B.V. All rights reserved.

Surgical strategies to improve fixation in the osteoporotic spine: the effects of tapping, cement augmentation, and screw trajectory.

PubMed

Kuhns, Craig A; Reiter, Michael; Pfeiffer, Ferris; Choma, Theodore J

2014-02-01

Study Design Biomechanical study of pedicle screw fixation in osteoporotic bone. Objective To investigate whether it is better to tap or not tap osteoporotic bone prior to placing a cement-augmented pedicle screw. Methods Initially, we evaluated load to failure of screws placed in cancellous bone blocks with or without prior tapping as well as after varying the depths of tapping prior to screw insertion. Then we evaluated load to failure of screws placed in bone block models with a straight-ahead screw trajectory as well as with screws having a 23-degree cephalad trajectory (toward the end plate). These techniques were tested with nonaugmented (NA) screws as well as with bioactive cement (BioC) augmentation prior to screw insertion. Results In the NA group, pretapping decreased fixation strength in a dose-dependent fashion. In the BioC group, the tapped screws had significantly greater loads to failure (p < 0.01). Comparing only the screw orientation, the screws oriented at 23 degrees cephalad had a significantly higher failure force than their respective counterparts at 0 degrees (p < 0.01). Conclusions Standard pedicle screw fixation is often inadequate in the osteoporotic spine, but this study suggests tapping prior to cement augmentation will substantially improve fixation when compared with not tapping. Angulating screws more cephalad also seems to enhance aging spine fixation.

A randomised study of ilio-inguinal nerve blocks following inguinal hernia repair: a stopped randomised controlled trial.

PubMed

Walker, Stuart; Orlikowski, Chris

2008-02-01

Local anaesthetic use for post-operative pain control is widely used following open inguinal hernia repair but this is not without risk. The aim of this study was to compare ilio-inguinal nerve block and wound irrigation in patients undergoing open inguinal hernia repair under general anaesthetic in a randomised, double blind, placebo controlled trial. Adult patients admitted for unilateral primary open mesh repair of an inguinal hernia were recruited. The patients received a standard general anaesthetic. Prior to skin incision, an ilio-inguinal injection was performed by the anaesthetist with either ropivicaine or normal saline. Prior to closure of the wound, the wound was irrigated with either ropivicaine or normal saline. Post-operatively, all patients received fentynal patient controlled analgesia and regular oral analgesia. Pain scores and visual analogue scores were recorded until discharge. Patients were then contacted by telephone at 24h, 48h, 2weeks and 4weeks post-operatively and asked a standard series of questions, mainly related to post-operative pain. After 12 patients had been recruited the trial was stopped as 5 of the 8 patients who received an ilio-inguinal nerve block suffered a neurological complication. Ilio-inguinal nerve block with ropivicaine should be avoided.

Chitosan adsorption on nanofibrillated cellulose with different aldehyde content and interaction with phosphate buffered saline.

PubMed

Ondaral, Sedat; Çelik, Elif; Kurtuluş, Orçun Çağlar; Aşıkuzun, Elif; Yakın, İsmail

2018-04-15

The chitosan adsorption on films prepared using nanofibrillated cellulose (NFC) with different content of aldehyde group was studied by means of Quartz Crystal Microbalance with Dissipation (QCM-D). Results showed that frequency change (Δf) was higher when the chitosan adsorbed on NFC film consisting more aldehyde group indicating the higher adsorption. The (Δf) and dissipation (ΔD) factors completely changed during adsorption of chitosan pre-treated with acetic acid: Δf increased and ΔD decreased, oppositely to un-treated chitosan adsorption. After acid treatment, molecular weight and crystallinity index of chitosan decreased addition to change in chemical structure. It was found that more phosphate buffered saline (PBS), as a model liquid for wound exudate, adsorbed to acid treated chitosan-NFC film, especially to film having more aldehyde groups. Comparing with bare NFC film, chitosan-NFC films adsorbed less PBS because chitosan crosslinked the NFC network and blocked the functional groups of NFC and thus, preventing swelling film. Copyright © 2017 Elsevier Ltd. All rights reserved.

DAQ application of PC oscilloscope for chaos fiber-optic fence system based on LabVIEW

NASA Astrophysics Data System (ADS)

Lu, Manman; Fang, Nian; Wang, Lutang; Huang, Zhaoming; Sun, Xiaofei

2011-12-01

In order to obtain simultaneously high sample rate and large buffer in data acquisition (DAQ) for a chaos fiber-optic fence system, we developed a double-channel high-speed DAQ application of a digital oscilloscope of PicoScope 5203 based on LabVIEW. We accomplished it by creating call library function (CLF) nodes to call the DAQ functions in the two dynamic link libraries (DLLs) of PS5000.dll and PS5000wrap.dll provided by Pico Technology Company. The maximum real-time sample rate of the DAQ application can reach 1GS/s. We can control the resolutions of the application at the sample time and data amplitudes by changing their units in the block diagram, and also control the start and end times of the sampling operations. The experimental results show that the application has enough high sample rate and large buffer to meet the demanding DAQ requirements of the chaos fiber-optic fence system.

Effect of oxide insertion layer on resistance switching properties of copper phthalocyanine

NASA Astrophysics Data System (ADS)

Joshi, Nikhil G.; Pandya, Nirav C.; Joshi, U. S.

2013-02-01

Organic memory device showing resistance switching properties is a next-generation of the electrical memory unit. We have investigated the bistable resistance switching in current-voltage (I-V) characteristics of organic diode based on copper phthalocyanine (CuPc) film sandwiched between aluminum (Al) electrodes. Pronounced hysteresis in the I-V curves revealed a resistance switching with on-off ratio of the order of 85%. In order to control the charge injection in the CuPc, nanoscale indium oxide buffer layer was inserted to form Al/CuPc/In2O3/Al device. Analysis of I-V measurements revealed space charge limited switching conduction at the Al/CuPc interface. The traps in the organic layer and charge blocking by oxide insertion layer have been used to explain the absence of resistance switching in the oxide buffer layered memory device cell. Present study offer potential applications for CuPc organic semiconductor in low power non volatile resistive switching memory and logic circuits.

77 FR 64820 - Notice of Submission of Proposed Information Collection to OMB Indian Housing Block Grants (IHBG...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-23

... submits the IHP at least 75 days prior to the beginning of its 12-month program year. HUD conducts a... that is required by Section 404 of NAHASDA and describes (1) The use of grant funds during the prior 12-month period; (2) the actual outcomes and outputs achieved; (3) program accomplishments; and (4) jobs...

The Course Evaluation System

DTIC Science & Technology

1987-03-01

lab exercise is only done once. -19 - Prior to classroom observation , complete the following steps: 1. Enter objective numbers on the first line of the...presentation component blocks that are not required for the objective task type. During classroom observation or during instructor and student guide...Adequacy Form. Prior to classroom observation complete the following steps: 1. Enter the objective number on each form. Only one objective is

Kidney Cell Electrophoresis

NASA Technical Reports Server (NTRS)

Todd, P.

1985-01-01

Materials and procedures for microgravity electrophoresis of living human embryonic kidney cells were evaluated, ground support in the form of analytical cell electrophoresis and flow cytometry was provided and cells returned from space flight were analyzed. Preflight culture media, electrophoresis buffer, fraction collection media, temperature profiles, and urokinase assay procedures were tested prior to flight. Electrophoretic mobility distributions of aliquots of the cell population to be fractionated in flight were obtained. The protocol established and utilized is given.

Activation of the medial prefrontal cortex by escapable stress is necessary for protection against subsequent inescapable stress-induced potentiation of morphine conditioned place preference.

PubMed

Rozeske, Robert R; Der-Avakian, Andre; Watkins, Linda R; Maier, Steven F

2012-01-01

Stress can be a predisposing factor in the development of psychiatric disorders. However, not all individuals develop psychiatric disorders following a traumatic event. An attempt to understand these individual differences has led to a focus on factors that produce resistance. Interestingly, in rats, an experience with escapable tailshock (ES) before inescapable tailshock (IS) prevents the typical anxiety-like behavioral outcomes of IS. This type of resistance has been termed 'behavioral immunization', and it depends on activation of the medial prefrontal cortex (mPFC) during ES. However, one outcome of IS that is not anxiety-related is potentiation of morphine conditioned place preference (CPP). The present experiments investigated whether prior ES would block IS-induced potentiation of morphine CPP. Rats received either ES, IS or homecage control treatment on day 1 and then either IS or homecage control treatment on day 2. Twenty-four hours following day 2, rats underwent morphine conditioning, and CPP was subsequently assessed. In a second experiment, rats received ES 3, 14 or 56 days prior to IS to determine the duration of behavioral immunization. In a final experiment, rats were microinjected with the GABA(A) agonist muscimol (50 ng/0.5 μL) or saline in the mPFC before day 1 of stress. Prior ES blocked IS-induced potentiation of morphine CPP. This immunizing effect of ES lasted for at least 56 days. Additionally, intra-mPFC muscimol during ES prevented behavioral immunization. These results suggest that prior experience with ES activates the mPFC and produces long-lasting neural alterations that block subsequent IS-induced potentiation of morphine CPP. © 2011 The Authors. European Journal of Neuroscience © 2011 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

Home-Made Cost Effective Preservation Buffer Is a Better Alternative to Commercial Preservation Methods for Microbiome Research

PubMed Central

Menke, Sebastian; Gillingham, Mark A. F.; Wilhelm, Kerstin; Sommer, Simone

2017-01-01

The investigation of wildlife gastrointestinal microbiomes by next-generation sequencing approaches is a growing field in microbial ecology and conservation. Such studies often face difficulties in sample preservation if neither freezing facilities nor liquid nitrogen (LQN) are readily available. Thus, in order to prevent microbial community changes because of bacterial growth after sampling, preservation buffers need to be applied to samples. However, the amount of microbial community variation attributable to the different preservation treatments and potentially affecting biological interpretation is hardly known. Here, we sampled feces of 11 sheep (Ovis aries sp.) by using swabs and analyzed the effect of air-drying, an inexpensive self-made nucleic acid preservation buffer (NAP), DNA/RNA Shield™, and RNAlater®, each together with freezing (for 10 days) or storing at room temperature (for 10 days) prior to 16S rRNA gene high-throughput sequencing to determine bacterial communities. Results revealed that the proportions of operational taxonomic units (OTUs) belonging to a bacterial phylum were affected by the preservation treatments, and that alpha diversities [observed OTUs, Shannon index, and phylogenetic diversity (PD)] were lower in all preservation treatments than in samples taken by forensic swabs and immediately frozen which is considered as the favored preservation treatment in the absence of any logistic constraints. Overall, NAP had better preservation qualities than RNAlater® and DNA/RNA Shield™ making this self-made buffer a valuable solution in wildlife microbiome studies. PMID:28197142

Home-Made Cost Effective Preservation Buffer Is a Better Alternative to Commercial Preservation Methods for Microbiome Research.

PubMed

Menke, Sebastian; Gillingham, Mark A F; Wilhelm, Kerstin; Sommer, Simone

2017-01-01

The investigation of wildlife gastrointestinal microbiomes by next-generation sequencing approaches is a growing field in microbial ecology and conservation. Such studies often face difficulties in sample preservation if neither freezing facilities nor liquid nitrogen (LQN) are readily available. Thus, in order to prevent microbial community changes because of bacterial growth after sampling, preservation buffers need to be applied to samples. However, the amount of microbial community variation attributable to the different preservation treatments and potentially affecting biological interpretation is hardly known. Here, we sampled feces of 11 sheep ( Ovis aries sp.) by using swabs and analyzed the effect of air-drying, an inexpensive self-made nucleic acid preservation buffer (NAP), DNA/RNA Shield™, and RNA later ®, each together with freezing (for 10 days) or storing at room temperature (for 10 days) prior to 16S rRNA gene high-throughput sequencing to determine bacterial communities. Results revealed that the proportions of operational taxonomic units (OTUs) belonging to a bacterial phylum were affected by the preservation treatments, and that alpha diversities [observed OTUs, Shannon index, and phylogenetic diversity (PD)] were lower in all preservation treatments than in samples taken by forensic swabs and immediately frozen which is considered as the favored preservation treatment in the absence of any logistic constraints. Overall, NAP had better preservation qualities than RNA later ® and DNA/RNA Shield™ making this self-made buffer a valuable solution in wildlife microbiome studies.

Responses to riparian restoration in the Spring Creek watershed, Central Pennsylvania

USGS Publications Warehouse

Carline, R.F.; Walsh, M.C.

2007-01-01

Riparian treatments, consisting of 3- to 4-m buffer strips, stream bank stabilization, and rock-lined stream crossings, were installed in two streams with livestock grazing to reduce sediment loading and stream bank erosion. Cedar Run and Slab Cabin Run, the treatment streams, and Spring Creek, an adjacent reference stream without riparian grazing, were monitored prior to (1991-1992) and 3-5 years after (2001-2003) riparian buffer installation to assess channel morphology, stream substrate composition, suspended sediments, and macroinvertebrate communities. Few changes were found in channel widths and depths, but channel-structuring flow events were rare in the drought period after restoration. Stream bank vegetation increased from 50% or less to 100% in nearly all formerly grazed riparian buffers. The proportion of fine sediments in stream substrates decreased in Cedar Run but not in Slab Cabin Run. After riparian treatments, suspended sediments during base flow and storm flow decreased 47-87% in both streams. Macroinvertebrate diversity did not improve after restoration in either treated stream. Relative to Spring Creek, macroinvertebrate densities increased in both treated streams by the end of the posttreatment sampling period. Despite drought conditions that may have altered physical and biological effects of riparian treatments, goals of the riparian restoration to minimize erosion and sedimentation were met. A relatively narrow grass buffer along 2.4 km of each stream was effective in improving water quality, stream substrates, and some biological metrics. ?? 2007 Society for Ecological Restoration International.

Effects of riparian timber harvesting on instream habitat and fish assemblages in northern Minnesota streams

USGS Publications Warehouse

Chizinski, Christopher J.; Vondracek, Bruce C.; Blinn, Charles R.; Newman, Raymond M.; Atuke, Dickson M.; Fredricks, Keith; Hemstad, Nathaniel A.; Merten, Eric; Schlesser, Nicholas

2010-01-01

Relatively few evaluations of aquatic macroinvertebrate and fish communities have been published in peer-reviewed literature detailing the effect of varying residual basal area (RBA) after timber harvesting in riparian buffers. Our analysis investigated the effects of partial harvesting within riparian buffers on aquatic macroinvertebrate and fish communities in small streams from two experiments in northern Minnesota northern hardwood-aspen forests. Each experiment evaluated partial harvesting within riparian buffers. In both experiments, benthic macroinvertebrates and fish were collected 1 year prior to harvest and in each of 3 years after harvest. We observed interannual variation for the macroinvertebrate abundance, diversity and taxon richness in the single-basin study and abundance and diversity in the multiple-basin study, but few effects related to harvest treatments in either study. However, interannual variation was not evident in the fish communities and we detected no significant changes in the stream fish communities associated with partially harvested riparian buffers in either study. This would suggest that timber harvesting in riparian management zones along reaches ≤200 m in length on both sides of the stream that retains RBA ≥ 12.4 ± 1.3 m2 ha−1 or on a single side of the stream that retains RBA ≥ 8.7 ± 1.6 m2 ha−1 may be adequate to protect macroinvertebrate and fish communities in our Minnesota study systems given these specific timber harvesting techniques.

Growth and characterization of CdS buffer layers by CBD and MOCVD

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

Morrone, A.A.; Huang, C.; Li, S.S.

1999-03-01

Thin film CdS has been widely used in thin-film photovoltaic devices. The most efficient Cu(In,&hthinsp;Ga)Se{sub 2} (CIGS) solar cells reported to date utilized a thin CdS buffer layer prepared by a reactive solution growth technique known as chemical bath deposition (CBD). Considerable effort has been directed to better understand the role and find a replacement for the CBD CdS process in CIGS-based solar cells. We reported a low temperature ({approximately}150&hthinsp;{degree}C) Metalorganic Chemical Vapor Deposition (MOCVD) CdS thin film buffer layer process for CIGS absorbers. Many prior studies have reported that CBD CdS contains a mixture of crystal structures. Recent investigationsmore » of CBD CdS thin films by ellipsometry suggested a multilayer structure. In this study we compare CdS thin films prepared by CBD and MOCVD and the effects of annealing. TED and XRD are used to characterize the crystal structure, the film microstructure is studied by HRTEM, and the optical properties are studied by Raman and spectrophotometry. All of these characterization techniques reveal superior crystalline film quality for CdS films grown by MOCVD compared to those grown by CBD. Dual Beam Optical Modulation (DBOM) studies showed that the MOCVD and CBD CdS buffer layer processes have nearly the same effect on CIGS absorbers when combined with a cadmium partial electrolyte aqueous dip. {copyright} {ital 1999 American Institute of Physics.}« less

[Anesthetic infiltration of the spermatic cord in surgery for voluminous hydrocele].

PubMed

Reale, C; Corinti, R; Galullo, B; Borgonuovo, P; Borgonuovo, P

1998-06-01

The use of a new technique in spermatic cord block in surgical treatment of large hydroceles is reported. Identification of the cord in these cases is often difficult due to the presence of the hydrocele. The reported technique consists in the percutaneous drainage of the hydrocele prior to the block, in order to allow an easier identification of the cord. The block is then performed by the usual method. 108 patients with large hydroceles (above 250 mls) underwent surgical repair employing this approach. In only one case the cord was not identified even after drainage due to the effects of a previous hernioplasty. In the remaining 107 patients the cord was easily identified and blocked. The excellent results obtained with this approach, show that cord block is possible in all patients, even when a large hydrocele is present.

1,25-Dihydroxyvitamin D3 Suppresses TLR8 Expression and TLR8-Mediated Inflammatory Responses in Monocytes In Vitro and Experimental Autoimmune Encephalomyelitis In Vivo

DTIC Science & Technology

2013-03-14

was supported by funding from the Telemedicine and Advanced Technology Research Center (TATRC) at the US Army Medical Research and Materiel Command...instructions. Specific primers were synthesized by Integrated DNA Technologies (San Diego, CA) as shown in Table S1. Real-time PCR was performed with SYBR...PFA for 1 h at 4uC and then permeablized in a buffer containing 0.1% saponin . Nonspecific antibody binding to Fc receptors was blocked by incubation

Hepatocyte Growth Factor Inhibits Apoptosis by the Profibrotic Factor Angiotensin II via Extracellular Signal-regulated Kinase 1/2 in Endothelial Cells and Tissue Explants

DTIC Science & Technology

2010-12-01

were subjected to SDS- polyacryl - amide gel electrophoresis and electroblotted onto nitrocellulose membrane. Membranes were blocked with 5% bovine...1 mM sodium fluoride, 0.1 mM sodium orthovanadate, 1 mM tetrasodium pyrophosphate, 2 mM phenylmethylsulfonyl fluoride, 10 g/ml leupeptin, and 10 g...buffer [50 mM Tris-HCl, 1 mM EGTA, 1% (wt/vol) CHAPS, 10% glycerol, 50 mM sodium fluoride, 1 mM sodium orthovanadate, 2 mM phenylmethylsulfonyl fluoride

Identification of the Gene for Scleroderma in the Tsk/2 Mouse Strain: Implications for Human Scleroderma Pathogenesis and subset Distinctions

DTIC Science & Technology

2014-07-01

onto an 8% SDS gel. Proteins were transferred to a polyvinylidene fluoride membrane, blocked in 5% nonfat milk in Tris-buffered saline, probed with...a)marker)of)fibrosis)[3,)4]),)we)assessed)both) protein )and)mRNA)levels)in)fibroblasts)that)received)DNA)from)a) plasmid)containing)a)single)allele...of)a)single)Col3a1%gene.)In)three)independent)experiments,)COL1A1) protein ) was)significantly)elevated)after)48)hours)of)transfection)with)Col3a1Tsk2

Deregulation of miRNAs Contributes to Development and Progression of Prostate Cancer

DTIC Science & Technology

2011-09-01

blocking with 5% non- fat dry milk in Tris-buffered saline/0.05% Tween 20 (TBST), the membrane was incubated with a specific primary antibody...androgen R1881, and p53 protein was detected by Western blot analysis. Consistent with our previous observation (2), untreated LNCaP-R273H cells expressed...Cell Biochem 2009; 106(3): 363–371. 7 Appendices Figure 1. Western blot analysis of p53 protein in 5.0 nM R1881-treated LNCaP cells and LNCaP-R273H

Involvement of noradrenergic and corticoid receptors in the consolidation of the lasting anxiogenic effects of predator stress.

PubMed

Adamec, R; Muir, C; Grimes, M; Pearcey, K

2007-05-16

The roles of beta-NER (beta-noradrenergic receptor), GR (glucocorticoid) and mineral corticoid receptors (MR) in the consolidation of anxiogenic effects of predator stress were studied. One minute after predator stress, different groups of rats were injected (ip) with vehicle, propranolol (beta-NER blocker, 5 and 10 mg/kg), mifepristone (RU486, GR blocker, 20 mg/kg), spironolactone (MR blocker, 50 mg/kg), propranolol (5 mg/kg) plus RU486 (20 mg/kg) or the anxiolytic, chloradiazepoxide (CPZ, 10 mg/kg). One week later, rodent anxiety was assessed in elevated plus maze, hole board, light/dark box, social interaction and acoustic startle. Considering all tests except startle, propranolol dose dependently blocked consolidation of lasting anxiogenic effects of predator stress in all tests. GR receptor block alone was ineffective. However, GR block in combination with an ineffective dose of propranolol did blocked consolidation of predator stress effects in all tests, suggesting a synergism between beta-NER and GR. Surprisingly, MR block prevented consolidation of anxiogenic effects in all tests except the light/dark box. CPZ post stress was ineffective against the anxiogenic impact of predator stress. Study of startle was complicated by the fact that anxiogenic effects of stress on startle amplitude manifested as both an increase and a decrease in startle amplitude. Suppression of startle occurred in stressed plus vehicle injected groups handled three times prior to predator stress. In contrast, stressed plus vehicle rats handled five times prior to predator stress showed increases in startle, as did all predator stressed only groups. Mechanisms of consolidation of the different startle responses appear to differ. CPZ post stress blocked startle suppression but not enhancement of startle. Propranolol post stress had no effect on either suppression or enhancement of startle. GR block alone post stress prevented suppression of startle, but not enhancement. In contrast blocking GR and beta-NER together prevented startle enhancement. MR block also prevented startle enhancement. Effects of MR block on startle suppression were not tested. Delay of habituation to startle was found in all stressed rats. Consolidation of delay of habituation was blocked or attenuated by post stress MR block, GR plus beta-NER block and CPZ but not by post stress GR or beta-NER block alone. Taken together, present findings suggest consolidation of lasting anxiogenic effects of predator stress may share some of the same neurochemical mechanisms implicated in some forms of fear memory consolidation. Implications of these findings for the study of stress-induced changes in affect including posttraumatic stress disorder (PTSD) are discussed.

Internet stream synchronization using Concord

NASA Astrophysics Data System (ADS)

Sreenan, Cormac J.; Narendran, B.; Agrawal, Prathima; Shivakumar, Narayanan

1996-03-01

Using packet networks to transport multimedia introduces delay variations within and across streams, necessitating synchronization at the receiver. This requires stream data to be buffered prior to presentation, which also increases its total end to end delay. Concord recognizes that applications may wish to influence the underlying synchronization policy in terms of its effect on quality of service. It provides a single framework for synchronization within and across streams and employs an application specific tradeoff between packet losses, delay and inter- stream skew. We present a new predictive approach for synchronization and a selection of results from an extensive evaluation of Concord for use in the Internet. A trace driven simulator is used, allowing a direct comparison with alternative approaches. We demonstrate that Concord can operate with lower maximum delay and less variation in total end to end delay, which in turn can allow receiver buffer requirements to be reduced.

Spatiotemporal Co-occurrence of Flanders and West Nile Viruses Within Culex Populations in Shelby County, Tennessee.

PubMed

Lucero, D E; Carlson, T C; Delisle, J; Poindexter, S; Jones, T F; Moncayo, A C

2016-05-01

West Nile virus (WNV) and Flanders virus (FLAV) can cocirculate in Culex mosquitoes in parts of North America. A large dataset of mosquito pools tested for WNV and FLAV was queried to understand the spatiotemporal relationship between these two viruses in Shelby County, TN. We found strong evidence of global clustering (i.e., spatial autocorrelation) and overlapping of local clustering (i.e., Hot Spots based on Getis Ord Gi*) of maximum likelihood estimates (MLE) of infection rates (IR) during 2008-2013. Temporally, FLAV emerges and peaks on average 10.2 wk prior to WNV based on IR. Higher levels of WNV IR were detected within 3,000 m of FLAV-positive pool buffers than outside these buffers. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Abrupt GaP/Si hetero-interface using bistepped Si buffer

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

Ping Wang, Y., E-mail: yanping.wang@insa-rennes.fr; Kuyyalil, J.; Nguyen Thanh, T.

We evidence the influence of the quality of the starting Si surface on the III-V/Si interface abruptness and on the formation of defects during the growth of III-V/Si heterogeneous crystal, using high resolution transmission electron microscopy and scanning transmission electron microscopy. GaP layers were grown by molecular beam epitaxy on vicinal Si (001). The strong effect of the Si substrate chemical preparation is first demonstrated by studying structural properties of both Si homoepitaxial layer and GaP/Si heterostructure. It is then shown that choosing adequate chemical preparation conditions and subsequent III-V regrowth conditions enables the quasi-suppression of micro-twins in the epilayer.more » Finally, the abruptness of GaP/Si interface is found to be very sensitive to the Si chemical preparation and is improved by the use of a bistepped Si buffer prior to III-V overgrowth.« less

Self-assembled block copolymer photonic crystal for selective fructose detection.

PubMed

Ayyub, Omar B; Ibrahim, Michael B; Briber, Robert M; Kofinas, Peter

2013-08-15

The use of one-dimensional photonic crystals fabricated from a self-assembled lamellar block copolymer as a sensitive and selective fructose sensor is investigated. The polystyrene-b-poly(2-vinyl pyridine) (PS-b-P2VP) films are functionalized with 2-(bromomethyl)phenylboronic acid. The boronic acid moiety confined within the lamellar morphology can reversibly bind to sugars such as fructose, imparting the photonic properties of the PS-b-P2VP film. The films exhibit a detection limit of 500 μM in water and 1mM in phosphate buffered saline. Exposure to a 50 mM solution of fructose invokes a highly visible color change from blue to orange. The films are also able to selectively recognize and respond to fructose in competitive studies in the presence of glucose, mannose and sucrose. Copyright © 2013 Elsevier B.V. All rights reserved.

Block Copolymer Micellization as a Protection Strategy for DNA Origami.

PubMed

Agarwal, Nayan P; Matthies, Michael; Gür, Fatih N; Osada, Kensuke; Schmidt, Thorsten L

2017-05-08

DNA nanotechnology enables the synthesis of nanometer-sized objects that can be site-specifically functionalized with a large variety of materials. For these reasons, DNA-based devices such as DNA origami are being considered for applications in molecular biology and nanomedicine. However, many DNA structures need a higher ionic strength than that of common cell culture buffers or bodily fluids to maintain their integrity and can be degraded quickly by nucleases. To overcome these deficiencies, we coated several different DNA origami structures with a cationic poly(ethylene glycol)-polylysine block copolymer, which electrostatically covered the DNA nanostructures to form DNA origami polyplex micelles (DOPMs). This straightforward, cost-effective, and robust route to protect DNA-based structures could therefore enable applications in biology and nanomedicine where unprotected DNA origami would be degraded. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chemical reactivation of quenched fluorescent protein molecules enables resin-embedded fluorescence microimaging

PubMed Central

Xiong, Hanqing; Zhou, Zhenqiao; Zhu, Mingqiang; Lv, Xiaohua; Li, Anan; Li, Shiwei; Li, Longhui; Yang, Tao; Wang, Siming; Yang, Zhongqin; Xu, Tonghui; Luo, Qingming; Gong, Hui; Zeng, Shaoqun

2014-01-01

Resin embedding is a well-established technique to prepare biological specimens for microscopic imaging. However, it is not compatible with modern green-fluorescent protein (GFP) fluorescent-labelling technique because it significantly quenches the fluorescence of GFP and its variants. Previous empirical optimization efforts are good for thin tissue but not successful on macroscopic tissue blocks as the quenching mechanism remains uncertain. Here we show most of the quenched GFP molecules are structurally preserved and not denatured after routine embedding in resin, and can be chemically reactivated to a fluorescent state by alkaline buffer during imaging. We observe up to 98% preservation in yellow-fluorescent protein case, and improve the fluorescence intensity 11.8-fold compared with unprocessed samples. We demonstrate fluorescence microimaging of resin-embedded EGFP/EYFP-labelled tissue block without noticeable loss of labelled structures. This work provides a turning point for the imaging of fluorescent protein-labelled specimens after resin embedding. PMID:24886825

Evidence for ˜80-75 Ma subduction jump during Anatolide-Tauride-Armenian block accretion and ˜48 Ma Arabia-Eurasia collision in Lesser Caucasus-East Anatolia

NASA Astrophysics Data System (ADS)

Rolland, Yann; Perincek, Dogan; Kaymakci, Nuretdin; Sosson, Marc; Barrier, Eric; Avagyan, Ara

2012-05-01

Orogens formed by a combination of subduction and accretion are featured by a short-lived collisional history. They preserve crustal geometries acquired prior to the collisional event. These geometries comprise obducted oceanic crust sequences that may propagate somewhat far away from the suture zone, preserved accretionary prism and subduction channel at the interplate boundary. The cessation of deformation is ascribed to rapid jump of the subduction zone at the passive margin rim of the opposite side of the accreted block. Geological investigation and 40Ar/39Ar dating on the main tectonic boundaries of the Anatolide-Tauride-Armenian (ATA) block in Eastern Turkey, Armenia and Georgia provide temporal constraints of subduction and accretion on both sides of this small continental block, and final collisional history of Eurasian and Arabian plates. On the northern side, 40Ar/39Ar ages give insights for the subduction and collage from the Middle to Upper Cretaceous (95-80 Ma). To the south, younger magmatic and metamorphic ages exhibit subduction of Neotethys and accretion of the Bitlis-Pütürge block during the Upper Cretaceous (74-71 Ma). These data are interpreted as a subduction jump from the northern to the southern boundary of the ATA continental block at 80-75 Ma. Similar back-arc type geochemistry of obducted ophiolites in the two subduction-accretion domains point to a similar intra-oceanic evolution prior to accretion, featured by slab steepening and roll-back as for the current Mediterranean domain. Final closure of Neotethys and initiation of collision with Arabian Plate occurred in the Middle-Upper Eocene as featured by the development of a Himalayan-type thrust sheet exhuming amphibolite facies rocks in its hanging-wall at c. 48 Ma.

Analgesic effects of maxillary and inferior alveolar nerve blocks in cats undergoing dental extractions.

PubMed

Aguiar, Joana; Chebroux, Alexandre; Martinez-Taboada, Fernando; Leece, Elizabeth A

2015-02-01

The aim of this study was to evaluate the analgesic effects of maxillary and/or inferior alveolar nerve blocks with lidocaine and bupivacaine in cats undergoing dental extractions. Twenty-nine cats were enrolled. Using an adapted composite pain scale, cats were pain scored before the dental procedure and 30 mins, and 1, 2 and 4 h after isoflurane disconnection. Cats were sedated with buprenorphine (20 µg/kg), medetomidine (10 µg/kg) and acepromazine (20 µg/kg) intramuscularly. Anaesthesia was induced using alfaxalone (1-2 mg/kg) intravenously and maintained with isoflurane in oxygen. Each cat was randomly assigned to receive maxillary and/or inferior alveolar nerve blocks or no nerve blocks prior to dental extractions. Each nerve block was performed using lidocaine (0.25 mg/kg) and bupivacaine (0.25 mg/kg). Heart rate, systolic arterial blood pressure, respiratory rate, end tidal carbon dioxide and isoflurane vaporiser settings were recorded 5 mins before and after the dental extractions, and the difference calculated. Group mean differences (mean ± SD) for heart rate (-9.7 ± 10.6 vs 7.6 ± 9.5 beats/min [nerve block vs control group, respectively], P <0.0001), systolic arterial blood pressure (-10.33 ± 18.44 vs 5.21 ± 15.23 mmHg, P = 0.02) and vaporiser settings (-0.2 ± 0.2 vs 0.1 ± 0.4, P = 0.023) were significantly different between groups. The control group had higher postoperative pain scores (median [interquartile range]) at 2 h (3 [1.75-4.00] vs 1 [0-2], P = 0.008) and 4 h (4 [2-6] vs 2 [1-2], P = 0.006) after the dental extractions. Maxillary and inferior alveolar nerve blocks with lidocaine and bupivacaine administered prior to dental extractions resulted in a reduction in heart rate and blood pressure while allowing for a reduction in isoflurane. Cats receiving nerve blocks had lower postoperative pain scores than the group without nerve blocks. © ISFM and AAFP 2014.

Acquired prior knowledge modulates audiovisual integration.

PubMed

Van Wanrooij, Marc M; Bremen, Peter; John Van Opstal, A

2010-05-01

Orienting responses to audiovisual events in the environment can benefit markedly by the integration of visual and auditory spatial information. However, logically, audiovisual integration would only be considered successful for stimuli that are spatially and temporally aligned, as these would be emitted by a single object in space-time. As humans do not have prior knowledge about whether novel auditory and visual events do indeed emanate from the same object, such information needs to be extracted from a variety of sources. For example, expectation about alignment or misalignment could modulate the strength of multisensory integration. If evidence from previous trials would repeatedly favour aligned audiovisual inputs, the internal state might also assume alignment for the next trial, and hence react to a new audiovisual event as if it were aligned. To test for such a strategy, subjects oriented a head-fixed pointer as fast as possible to a visual flash that was consistently paired, though not always spatially aligned, with a co-occurring broadband sound. We varied the probability of audiovisual alignment between experiments. Reaction times were consistently lower in blocks containing only aligned audiovisual stimuli than in blocks also containing pseudorandomly presented spatially disparate stimuli. Results demonstrate dynamic updating of the subject's prior expectation of audiovisual congruency. We discuss a model of prior probability estimation to explain the results.

Resilient self-assembling hydrogels from block copolypeptide amphiphiles

NASA Astrophysics Data System (ADS)

Nowak, Andrew Paul

The ability to produce well defined synthetic polypeptides has been greatly improved by the discovery of transition metal species that mediate the controlled polymerization of N-carboxyanhydrides (NCAs). These metal species create a living polymerization system by producing control over chain length, low polydispersities, and the ability to form complex block architectures. We have applied this system to the synthesis of block copolypeptide amphiphiles. Initial block copolymers synthesized were composed of hydrophilic, cationic poly(L-Lysine) combined with hydrophobic, alpha-helical poly(L-Leucine). These Lysine- block-Leucine copolypeptides were found to form stiff, clear hydrogels at low concentration (˜1 wt%) in low ionic strength water. Based on this unexpected result we used the flexibility of our transition metal polymerization chemistry to better understand the nature and mechanisms of gel formation in these materials. Systematic changes to the original Lysine-block-Leucine copolypeptides were made by altering overall chain size, relative block length, polyelectrolyte charge, and hydrophobic secondary structure. Rheological characterization revealed that the strength of these hydrogels was primarily dependent on degree of polymerization, relative block length, and a well ordered secondary structure in the hydrophobic segment. The Lysine-block-Leucine hydrogels were formed by direct addition of water to dry polypeptide material which swelled to homogeneously fill the entire volume of liquid with no special processing. CryoTEM showed a percolating cellular network at ˜100nm that appears to be comprised of both membranes and fibers. Larger length scales studied with Laser Scanning Confocal Microscopy revealed a spontaneously formed microporous network with large (˜10mum) water rich voids. These hydrogels also displayed interesting mechanical properties including rapid recovery of solid like behavior after being sheared to a liquid and mechanical stability with increased temperature (˜90°C). The behavior of the Lysine- block-Leucine system with salt was also thoroughly investigated. With proper tuning of the relative block composition it was found that hydrogels could be optimized to possess good solubility and mechanical strength in many useful ionic solutions (˜100--200mM) such as pH buffers and cell culture media.

A low-latency optical switch architecture using integrated μm SOI-based contention resolution and switching

NASA Astrophysics Data System (ADS)

Mourgias-Alexandris, G.; Moralis-Pegios, M.; Terzenidis, N.; Cherchi, M.; Harjanne, M.; Aalto, T.; Vyrsokinos, K.; Pleros, N.

2018-02-01

The urgent need for high-bandwidth and high-port connectivity in Data Centers has boosted the deployment of optoelectronic packet switches towards bringing high data-rate optics closer to the ASIC, realizing optical transceiver functions directly at the ASIC package for high-rate, low-energy and low-latency interconnects. Even though optics can offer a broad range of low-energy integrated switch fabrics for replacing electronic switches and seamlessly interface with the optical I/Os, the use of energy- and latency-consuming electronic SerDes continues to be a necessity, mainly dictated by the absence of integrated and reliable optical buffering solutions. SerDes undertakes the role of optimally synergizing the lower-speed electronic buffers with the incoming and outgoing optical streams, suggesting that a SerDes-released chip-scale optical switch fabric can be only realized in case all necessary functions including contention resolution and switching can be implemented on a common photonic integration platform. In this paper, we demonstrate experimentally a hybrid Broadcast-and-Select (BS) / wavelength routed optical switch that performs both the optical buffering and switching functions with μm-scale Silicon-integrated building blocks. Optical buffering is carried out in a silicon-integrated variable delay line bank with a record-high on-chip delay/footprint efficiency of 2.6ns/mm2 and up to 17.2 nsec delay capability, while switching is executed via a BS design and a silicon-integrated echelle grating, assisted by SOA-MZI wavelength conversion stages and controlled by a FPGA header processing module. The switch has been experimentally validated in a 3x3 arrangement with 10Gb/s NRZ optical data packets, demonstrating error-free switching operation with a power penalty of <5dB.

Fluvial entrainment of low density peat blocks (block carbon)

NASA Astrophysics Data System (ADS)

Warburton, Jeff

2014-05-01

In many fluvial environments low density materials are transported in significant quantities and these form an important part of the stream load and /or have a distinct impact on sedimentation in these environments. However, there are significant gaps in understanding of how these materials are entrained and transported by streams and rivers. Eroding upland peatland environments in particular, frequently have fluvial systems in which large eroded peat blocks, often exceeding 1 m in length; form an important component of the stream material flux. Transport of this material is significant in determining rates of erosion but also has important impacts in terms of damage to infrastructure and carbon loss. This paper describes a field experiment designed to establish for the first time the conditions under which large peat blocks (c. > 0.1 m b axis) are initially entrained from a rough gravel bed. The field site is Trout Beck, in the North Pennines, Northern England which is an upland wandering river channel with occasional lateral and mid channel bars. Mean low flow stage is typically 0.2 m but during flood can rapidly rise, in one to two hours, to over 1.5 m. To study peat block entrainment a bespoke data acquisition system consisting of two pressure transducers, four release triggers and time lapse camera was set up. The pressure transducers provided a record of local depth and the release triggers were embedded in peat blocks to record initial motion and arranged on the rough stream bed. The time lapse camera provided verification of timing of block entrainment (during daylight hours) and also provided information on the mechanism of initial movement. Peat blocks were cut from a local source and were equidimensional, ranging in size from 0.1 to 0.7 m. The derived entrainment function is related to a critical depth of entrainment. Results demonstrate that peat blocks are entrained when the local depth approximates the height of the peat block. Blocks frequently shift position prior to entrainment but once entrained are rapidly transported downstream. Because of the rough stream bed local depth, measured on the four sides of the block varies markedly and needs to be considered in developing an appropriate entrainment function and; is useful in explaining initial movement prior to entrainment. In some experiments a small accelerometer (HOBO Pendant G data logger) was used to investigate transport dynamics following entrainment. Further work will seek to improve the entrainment function by extending the size range of tests, developing a shear stress related function and investigating the importance of block shape (rounding) on entrainment.

Static magnetic field blood pressure buffering, baroreflex vs. vascular blood pressure control mechanism.

PubMed

Gmitrov, Juraj

2010-02-01

We compared the effect of static magnetic field (SMF) and verapamil, a potent vascular calcium channel blocking agent, on sudden elevation in blood pressure in conjunction with arterial baroreflex sensitivity (BRS) and microcirculation. Forty-four experiments were performed on conscious rabbits sedated using pentobarbital intravenous (i.v.) infusion (5 mg kg(-1) h(-1)). Mean femoral artery blood pressure (MAP), heart rate, BRS and ear lobe skin microcirculatory blood flow, estimated using microphotoelectric plethysmography (MPPG), were simultaneously measured after a 40 min exposure of the sinocarotid baroreceptors to 350 mT SMF, generated by Nd(2)-Fe(14)-B magnets, or 30 min of verapamil i.v. administration (20 microg kg(-1) min(-1)). BRS was assessed from heart rate and MAP responses to i.v. bolus of nitroprusside and phenylephrine. The decrease in phenylephrine-induced abrupt elevation in MAP (DeltaMAP(AE)) was significantly larger after verapamil than after SMF exposure. DeltaMAP(AE) inversely correlated with verapamil-induced significant increase in DeltaMPPG (r = 0.53, p < 0.000) and with SMF-induced significant increase in DeltaBRS (r = 0.47, p < 0.016). Our results suggest that verapamil-potentiated vascular blood pressure buffering mechanism was more effective than SMF-potentiated baroreflex-mediated blood pressure buffering mechanism, and a potential benefit of both approaches in cardiovascular conditions with abrupt high elevation in blood pressure.

The effects of thermal stimuli on intracellular calcium change and histamine releases in rat basophilic leukemia mast cells

NASA Astrophysics Data System (ADS)

Wu, Zu-Hui; Zhu, Dan; Chen, Ji-Yao; Zhou, Lu-Wei

2012-05-01

The effects of thermal stimuli on rat basophilic leukemia mast cells were studied. The cells in calcium-contained or calcium-free buffers were thermally stimulated in the temperature range of 25-60 °C. The corresponding calcium ion concentration in cells [Ca2+]i as well as the released histamine from cells was measured with fluorescence staining methods. The ruthenium red (RR), a block of membrane calcium channels (transient receptor potential family V (TRPV)), was used in experiments. Under the stimulus of 25-50 °C, no significant difference on [Ca2+]i was found between these three groups of the cells in calcium-contained buffer without or with RR and cells in calcium-free saline, indicating that the increased calcium in cytosol did not result from the extracellular buffer but came from the intracellular calcium stores. The [Ca2+]i continuously increased under the temperature of 50-60 °C, but the RR and calcium-free saline can obviously diminish the [Ca2+]i increase at these high temperatures, reflecting that the opening of the TRPV2 channels leads to a calcium influx resulting in the [Ca2+]i increment. The histamine release also became significant in these cases. Since the released histamine is a well-known mediator for the microcirculation promotion, the histamine release from mast cells could be one of the mechanisms of thermal therapy.

Flexible video conference system based on ASICs and DSPs

NASA Astrophysics Data System (ADS)

Hu, Qiang; Yu, Songyu

1995-02-01

In this paper, a video conference system we developed recently is presented. In this system the video codec is compatible with CCITT H.261, the audio codec is compatible with G.711 and G.722, the channel interface circuit is designed according to CCITT H.221. In this paper emphasis is given to the video codec, which is both flexible and robust. The video codec is based on LSI LOGIC Corporation's L64700 series video compression chipset. The main function blocks of H.261, such as DCT, motion estimation, VLC, VLD, are performed by this chipset, but the chipset is a nude chipset, no peripheral function, such as memory interface, is integrated into it, this results in great difficulty to implement the system. To implement the frame buffer controller, a DSP-TMS 320c25 and a group of GALs is used, SRAM is used as a current and previous frame buffer, the DSP is not only the controller of the frame buffer, it's also the controller of the whole video codec. Because of the use of the DSP, the architecture of the video codec is very flexible, many system parameters can be reconfigured for different applications. The architecture of the whole video codec is a streamline structure. In H.261, BCH(511,493) coding is recommended to work against random errors in transmission, but if burst error occurs, it causes serious result. To solve this problem, an interleaving method is used, that means the BCH code is interleaved before it's transmitted, in the receiver it is interleaved again and the bit stream is in the original order, but the error bits are distributed into several BCH words, and the BCH decoder is able to correct it. Considering that extreme conditions may occur, a function block is implemented which is somewhat like a watchdog, it assures that the receiver can recover from errors no matter what serious error occurs in transmission. In developing the video conference system, a new synchronization problem must be solved, the monitor on the receiver can't be easily synchronized with the camera on another side, a new method is described in detail which can solve this problem successfully.

Development of textured magnesium oxide templates and bicrystals using ion beam assisted deposition

NASA Astrophysics Data System (ADS)

Vallejo, Ronald N.

Recently, there has been an increased research effort in the deposition of near-single-crystal thin films on substrates that do not provide a template for epitaxial crystalline film growth. Ion beam assisted deposition (IBAD) has been demonstrated as one of the most promising methods to artificially control the texture in thin films. Biaxially textured MgO templates of 10 nm thickness were successfully fabricated on glass and silicon substrates without any buffer layers using IBAD. This work has shed insights on several issues. First, surface morphology ˜ 1 nm or better is only a necessary condition for textured IBAD-MgO, but not a sufficient condition. Additional surface preparation must be provided for nucleation and subsequent formation of the textured IBAD-MgO templates. Second, the role of buffer layer on IBAD-MgO texturing. It was found that the ion beam pre-exposure of the substrates prior to IBAD processing provided a sufficient condition for the nucleation and subsequent texture formation of the IBAD grown films. The ion pre-exposure replaced the need for buffer layers in silicon and glass substrates. Finally, by pre-exposing the substrates to Ar + ions, it was found that the ion beam modified the surface and improved the surface roughness of the glass substrates. Textured MgO epi templates were demonstrated for the first time on polymer based substrates (polyimide). This is a crucial step in the realization of epitaxial suspended devices. To achieve an epitaxial film on a sacrificial layer, an epitaxial template film must first be grown prior to subsequent film growth. The role of ion pre-exposure and buffer layer on texture formation was investigated in this part of the work. This thesis also presents groundbreaking results on the fabrication of bicrystal MgO films and bicrystal networks using ion beam assisted deposition. Highly oriented bicrystals, with a common (100) out-of-plane orientation and (110) in-plane orientations having a tilt angle of 45° and 20° have been successfully fabricated. This method has also been used to fabricate two dimensional bicrystal MgO networks in the micrometer scale. The same strategy can be applied to generate nanometer scale bicrystal networks of desired patterns.

Effectiveness of 20% benzocaine as a topical anesthetic for intraoral injections.

PubMed Central

Nusstein, John M.; Beck, Mike

2003-01-01

The use of topical anesthetics has been advocated prior to the administration of various types of anesthetic injections. Reported results have varied between studies. The purpose of this study was to compare the effectiveness of 20% benzocaine in reducing the pain of needle insertion during maxillary posterior and anterior infiltration and inferior alveolar nerve block injections. In this retrospective study, 1080 patients received 2336 injections using a 27-gauge needle. Topical anesthetic was applied prior to 720 of the injections. Patients rated pain of needle insertion using a 0-4 pain scale. Logistic regression analysis showed no differences in pain ratings between topical and no topical groups for the inferior alveolar nerve block and posterior maxillary infiltration injections. The use of topical anesthetic did reduce the pain of needle insertion with the maxillary anterior injections (P = .0041). PMID:14959903

Using cluster analysis to organize and explore regional GPS velocities

USGS Publications Warehouse

Simpson, Robert W.; Thatcher, Wayne; Savage, James C.

2012-01-01

Cluster analysis offers a simple visual exploratory tool for the initial investigation of regional Global Positioning System (GPS) velocity observations, which are providing increasingly precise mappings of actively deforming continental lithosphere. The deformation fields from dense regional GPS networks can often be concisely described in terms of relatively coherent blocks bounded by active faults, although the choice of blocks, their number and size, can be subjective and is often guided by the distribution of known faults. To illustrate our method, we apply cluster analysis to GPS velocities from the San Francisco Bay Region, California, to search for spatially coherent patterns of deformation, including evidence of block-like behavior. The clustering process identifies four robust groupings of velocities that we identify with four crustal blocks. Although the analysis uses no prior geologic information other than the GPS velocities, the cluster/block boundaries track three major faults, both locked and creeping.

Combination of a pressure source and block movement for ground deformation analysis at Merapi volcano prior to the eruptions in 2006 and 2010

NASA Astrophysics Data System (ADS)

Aisyah, Nurnaning; Iguchi, Masato; Subandriyo; Budisantoso, Agus; Hotta, Kohei; Sumarti, Sri

2018-05-01

We analyzed ground deformation prior to the eruptions in 2006 and 2010 at Merapi volcano, Central Java, Indonesia. Ground deformation was monitored by electronic distance measurement (EDM) by measuring the slope distance toward 12 reflectors installed near the summit from five benchmarks on flanks every day. A large change of slope distance (CSD) was detected on the southeast and south baselines and a minor CSD was detected on the north and northwest baselines during the pre-eruptive stages of both the 2006 and 2010 eruptions. We applied a block movement model to the south and southeast baselines and a spherical pressure source model to the CSDs on the north and northwest baselines using the finite element method (FEM). The rates of block movement southward and the volume change of the pressure source increased on April 7, 2006 and continued at constant rates until the appearance of a new lava dome on April 26. Prior to the eruption in 2010, the block movement southeastward and the volume increase of the pressure source accelerated in the middle of October, and acceleration continued until the first outburst on October 26, 2010. Temporal patterns of the block movement and the increase in the volume of the pressure source correlate well with the increase in seismicity of VT and MP earthquakes. The pressure sources were obtained at a depth of 2 ± 0.5 km below the summit, and this position corresponds to the aseismic zone of VT earthquakes. Magma injection at the shallow part of this region causes an increase in the volume of the pressure source, and inflation of the ground of the summit triggered gravitational slip southeastward or southward of the ground surface. The volumes increases of the pressure sources were 9.7 ± 1 M m3 and 17.6 ± 0.8 M m3 in 2006 and 2010, respectively. The volume increase is related to the scale and type of the eruption. The effusive eruption in 2006 had a volcanic explosivity index (VEI) of 2 and the explosive eruption in 2010 had a VEI of 4. The directions and amounts of the block movement are strongly related to topography, hydrothermally weak zone and underground gap near the summit between West and East Domes.

Development of Test Article Building Block (TABB) for deployable platform systems

NASA Technical Reports Server (NTRS)

Greenberg, H. S.; Barbour, R. T.

1984-01-01

The concept of a Test Article Building Block (TABB) is described. The TABB is a ground test article that is representative of a future building block that can be used to construct LEO and GEO deployable space platforms for communications and scientific payloads. This building block contains a main housing within which the entire structure, utilities, and deployment/retraction mechanism are stowed during launch. The end adapter secures the foregoing components to the housing during launch. The main housing and adapter provide the necessary building-block-to-building-block attachments for automatically deployable platforms. Removal from the shuttle cargo bay can be accomplished with the remote manipulator system (RMS) and/or the handling and positioning aid (HAPA). In this concept, all the electrical connections are in place prior to launch with automatic latches for payload attachment provided on either the end adapters or housings. The housings also can contain orbiter docking ports for payload installation and maintenance.

Fouling and Boring of Glass Reinforced Plastic - Balsa Blocks in a Tropical Marine Environment,

DTIC Science & Technology

1983-03-01

borers had decomposed prior to examination of the blocks but eight molluscan species were identified from hard parts (pallets and shells ) found in the...or bivalve molluscs and these differ in their boring habit and subsequently the type of damage they cause. Crustacean borers excavate tunnels several...or teredo, excavate tunnels lined with calcium carbonate to accomodate their elongate bodies which, in some species, can be up to 2m long. They feed

Image Processing Research

DTIC Science & Technology

1975-09-30

systems a linear model results in an object f being mappad into an image _ by a point spread function matrix H. Thus with noise j +Hf +n (1) The simplest... linear models for imaging systems are given by space invariant point spread functions (SIPSF) in which case H is block circulant. If the linear model is...Ij,...,k-IM1 is a set of two dimensional indices each distinct and prior to k. Modeling Procedare: To derive the linear predictor (block LP of figure

Efficacy of cancellous block allograft augmentation prior to implant placement in the posterior atrophic mandible.

PubMed

Nissan, Joseph; Ghelfan, Oded; Mardinger, Ofer; Calderon, Shlomo; Chaushu, Gavriel

2011-12-01

The present study evaluated the outcome of ridge augmentation with cancellous freeze-dried block bone allografts in the posterior atrophic mandible followed by placement of dental implants. A bony deficiency of at least 3 mm, horizontally, vertically, or both, according to computerized tomography (CT) para-axial reconstruction served as inclusion criteria. Implants were inserted after a healing period of 6 months. Bone measurements were taken prior to bone augmentation, during implant placement, and at second-stage surgery. Marginal bone loss and crown-to-implant ratio were also measured. Twenty-nine cancellous allogeneic bone blocks were placed in 21 patients. The mean follow-up was 37 months. Bone block survival rate was 79.3%. Mean horizontal and vertical bone gains were 5.6 and 4.3 mm, respectively. Mean buccal bone resorption was 0.5 mm at implant placement and 0.2 mm at second-stage surgery. A total of 85 implants were placed. Mean bone thickness buccal to the implant neck was 2.5 mm at implant placement and 2.3 mm at second-stage surgery. There was no evidence of vertical bone loss between implant placement and second-stage surgery. Implant survival rate was 95.3%. All patients received a fixed implant-supported prosthesis. At the last follow-up, the mean marginal bone loss was 0.5 mm. The mean crown-to-implant ratio was 0.96. Implant placement in the posterior atrophic mandible following augmentation with cancellous freeze-dried bone block allografts may be regarded as a viable treatment alternative. © 2009 Wiley Periodicals, Inc.

Structural, Electrical and Optical Properties of Sputtered-Grown InN Films on ZnO Buffered Silicon, Bulk GaN, Quartz and Sapphire Substrates

NASA Astrophysics Data System (ADS)

Bashir, Umar; Hassan, Zainuriah; Ahmed, Naser M.; Afzal, Naveed

2018-05-01

Indium nitride (InN) films were grown on Si (111), bulk GaN, quartz and sapphire substrates by radio frequency magnetron sputtering. Prior to the film deposition, a zinc oxide (ZnO) buffer layer was deposited on all the substrates. The x-ray diffraction patterns of InN films on ZnO-buffered substrates indicated c-plane-oriented films whereas the Raman spectroscopy results indicated A1 (LO) and E2 (high) modes of InN on all the substrates. The crystalline quality of InN was found to be better on sapphire and quartz than on the other substrates. The surface roughness of InN was studied using an atomic force microscope. The results indicated higher surface roughness of the film on sapphire as compared to the others; however, roughness of the film was lower than 8 nm on all the substrates. The electrical properties indicated higher electron mobility of InN (20.20 cm2/Vs) on bulk GaN than on the other substrates. The optical band gap of InN film was more than 2 eV in all the cases and was attributed to high carrier concentration in the film.

GABA/sub B/ receptor activation inhibits Ca/sup 2 +/-activated potassium channels in synaptosomes: involvement of G-proteins

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

Ticku, M.K.; Delgado, A.

1989-01-01

/sup 86/Rb-efflux assay from preloaded synaptosomes of rat cerebral cortex was developed to study the effect of GABA/sub B/ receptor agonist baclofen on Ca/sup 2 +/-activated K/sup +/-channels. Depolarization of /sup 86/Rb-loaded synaptosomes in physiological buffer increased Ca/sup 2 +/-activated /sup 86/Rb-efflux by 400%. The /sup 86/Rb-efflux was blocked by quinine sulfate, tetraethylammonium, and La/sup 3 +/ indicating the involvement of Ca/sup 2 +/-activated K/sup +/-channels. (-)Baclofen inhibited Ca/sup 2 +/-activated /sup 86/Rb-efflux in a stereospecific manner. The inhibitory effect of (-)baclofen was mediated by GABA/sub B/ receptor activation, since it was blocked by GABA/sub B/ antagonist phaclofen, but notmore » by bicuculline. Further, pertussis toxin also blocked the ability of baclofen or depolarizing action to affect Ca/sup 2 +/-activated K/sup +/-channels. These results suggest that baclofen inhibits Ca/sup 2 +/-activated K/sup +/-channels in synaptosomes and these channels are regulated by G-proteins. This assay may provide an ideal in vitro model to study GABA/sub B/ receptor pharmacology.« less

Motion compensation in digital subtraction angiography using graphics hardware.

PubMed

Deuerling-Zheng, Yu; Lell, Michael; Galant, Adam; Hornegger, Joachim

2006-07-01

An inherent disadvantage of digital subtraction angiography (DSA) is its sensitivity to patient motion which causes artifacts in the subtraction images. These artifacts could often reduce the diagnostic value of this technique. Automated, fast and accurate motion compensation is therefore required. To cope with this requirement, we first examine a method explicitly designed to detect local motions in DSA. Then, we implement a motion compensation algorithm by means of block matching on modern graphics hardware. Both methods search for maximal local similarity by evaluating a histogram-based measure. In this context, we are the first who have mapped an optimizing search strategy on graphics hardware while paralleling block matching. Moreover, we provide an innovative method for creating histograms on graphics hardware with vertex texturing and frame buffer blending. It turns out that both methods can effectively correct the artifacts in most case, as the hardware implementation of block matching performs much faster: the displacements of two 1024 x 1024 images can be calculated at 3 frames/s with integer precision or 2 frames/s with sub-pixel precision. Preliminary clinical evaluation indicates that the computation with integer precision could already be sufficient.

The influence of partial timber harvest in riparian management zones on macroinvertebrate and fish communities on first- and second-order streams in northern Minnesota

USGS Publications Warehouse

Chizinski, Christopher J.; Vondracek, Bruce C.; Blinn, Charles R.; Newman, Raymond M.; Atuke, Dickson M.; Fredricks, Keith; Hemstad, Nathaniel A.; Merten, Eric; Schlesser, Nicholas

2010-01-01

Relatively few evaluations of aquatic macroinvertebrate and fish communities have been published in peer-reviewed literature detailing the effect of varying residual basal area (RBA) after timber harvesting in riparian buffers. Our analysis investigated the effects of partial harvesting within riparian buffers on aquatic macroinvertebrate and fish communities in small streams from two experiments in northern Minnesota northern hardwood-aspen forests. Each experiment evaluated partial harvesting within riparian buffers. In both experiments, benthic macroinvertebrates and fish were collected 1 year prior to harvest and in each of 3 years after harvest. We observed interannual variation for the macroinvertebrate abundance, diversity and taxon richness in the single-basin study and abundance and diversity in the multiple-basin study, but few effects related to harvest treatments in either study. However, interannual variation was not evident in the fish communities and we detected no significant changes in the stream fish communities associated with partially harvested riparian buffers in either study. This would suggest that timber harvesting in riparian management zones along reaches ≤200 m in length on both sides of the stream that retains RBA ≥ 12.4 ± 1.3 m2 ha−1 or on a single side of the stream that retains RBA ≥ 8.7 ± 1.6 m2 ha−1 may be adequate to protect macroinvertebrate and fish communities in our Minnesota study systems given these specific timber harvesting techniques.

Stress, Social Support and Problem Drinking among Women in Poverty

PubMed Central

Mulia, Nina; Schmidt, Laura; Bond, Jason; Jacobs, Laurie; Korcha, Rachael

2009-01-01

Aims Prior studies find that stress contributes to problem drinking while social support can buffer its effects. However, these studies are largely confined to middle class and general populations. We extend what is known by examining how the unique stressors and forms of social support experienced by women in poverty impact alcohol problems over a 4-year time period. Design and Participants This prospective study used GEE transition modeling and 4 annual waves of survey data from 392 American mothers receiving Temporary Assistance for Needy Families (TANF) in a large Northern California county. Measurements We examined the effects of neighborhood disorder, stressful life events and economic hardship on psychological distress and problem drinking over time, and whether social support moderated these relationships for women in poverty. Findings Neighborhood disorder and stressful life events significantly increased the risk for problem drinking, largely through their effect on psychological distress. We found little evidence, however, that social support buffers poor women from the effects of these stressors. Conclusions Women in poverty are exposed to severe, chronic stressors within their communities and immediate social networks which increase vulnerability to psychological distress and problem drinking. The finding that social support does not buffer stress among these women may reflect their high level of exposure to stressors, as well as the hardships and scarce resources within their networks. If the “private safety net” of the social network fails to provide a strong buffer, more effective environmental interventions that reduce exposure to stressors may be needed to prevent alcohol problems in poor women’s lives. PMID:18855817

Enhanced dielectric properties of Pb0.92La0.08 Zr0.52Ti0.48O3 films with compressive stress

NASA Astrophysics Data System (ADS)

Ma, Beihai; Liu, Shanshan; Tong, Sheng; Narayanan, Manoj; (Balu) Balachandran, U.

2012-12-01

We deposited ferroelectric (Pb0.92La0.08)(Zr0.52Ti0.48)O3 (PLZT 8/52/48) films on nickel foils and platinized silicon (PtSi) substrates by chemical solution deposition. Prior to the deposition of PLZT, a conductive oxide buffer layer of LaNiO3 (LNO) was deposited on the nickel foil. Residual stresses of the films were determined by x-ray diffraction. Compressive stress of ≈-370 MPa and tensile stress of ≈250 MPa were measured in ≈2-μm-thick PLZT grown on LNO-buffered Ni foil and PtSi substrate, respectively. We also measured the following electrical properties for the PLZT films grown on LNO-buffered Ni and PtSi substrates, respectively: remanent polarization, ≈23.5 μC/cm2 and ≈10.1 μC/cm2; coercive electric field, ≈23.8 kV/cm and ≈27.9 kV/cm; dielectric constant at room temperature, ≈1300 and ≈1350; and dielectric loss at room temperature, ≈0.06 and ≈0.05. Weibull analysis determined the mean breakdown strength to be 2.6 MV/cm and 1.5 MV/cm for PLZT films grown on LNO-buffered Ni and PtSi substrates, respectively. The difference in dielectric properties and breakdown strength can be attributed to the residual stress in the PLZT films. Our results suggest that compressive stress enhances the dielectric breakdown strength of the PLZT films.

Synthesis, characterization, and biocompatibility of alternating block polyurethanes based on PLA and PEG.

PubMed

Mei, Tingzhen; Zhu, Yonghe; Ma, Tongcui; He, Tao; Li, Linjing; Wei, Chiju; Xu, Kaitian

2014-09-01

A series of alternating block polyurethanes (abbreviated as PULA-alt-PEG) and random block polyurethanes (abbreviated as PULA-ran-PEG) based on poly(L-lactic acid) (PLA) and poly(ethylene glycol) (PEG) were synthesized. The differences of PULA-alt/ran-PEG chemical structure, molecular weight, distribution, thermal properties, mechanical properties and static contact angle were systematically investigated. The PULA-alt/ran-PEG polyurethanes exhibited low T(g) (-47.3 ∼ -34.4°C), wide mechanical properties (stress σ(t): 4.6-32.6 MPa, modulus E: 11.4-323.9 MPa and strain ε: 468-1530%) and low water contact angle (35.4-51.4°). Scanning electron microscope (SEM) observation showed that PULA-alt-PEG film displays rougher and more patterned surface morphology than PULA-ran-PEG does, due to more regular structures of PULA-alt-PEG. Hydrolytic degradation shows that degradation rate of random block polyurethane series PULA-ran-PEG is higher than the alternating counterpart PULA-alt-PEG. PLA segment degradation is faster than urethane linkage and PEG segment almost does not degrade in the buffer solution. Platelet adhesion study showed that all the polyurethanes possess excellent hemocompatibility. The cell culture assay revealed that PULA-alt/ran-PEG polyurethanes were cell inert and unfavorable for the attachment of rat glial cell due to the hydrophilic characters of the materials. © 2013 Wiley Periodicals, Inc.

Effects of block length on the enzymatic degradation and erosion of oxazoline linked poly-epsilon-caprolactone.

PubMed

Pulkkinen, Mika; Malin, Minna; Tarvainen, Tommy; Saarimäki, Tiina; Seppälä, Jukka; Järvinen, Kristiina

2007-06-01

The aim of the study was to develop enzyme sensitive polymers for pharmaceutical applications. Thus, 2,2'-bis(2-oxazoline)-linked poly-epsilon-caprolactone (PCL-O) polymers were synthesized by using epsilon-caprolactone precursors with different molecular weights (M(n): 1500, 3900, 7500 and 12,000g/mol), and the effects of PCL block length on enzymatic degradation and erosion (weight loss) of PCL-O films were studied. Solvent cast PCL and PCL-O films were incubated (22 days) in the presence of pancreatin (1%, pH 7.5), with and without enzyme inhibitors. In the absence of enzyme inhibitors, surface erosion of the PCL-O films occurred during incubation, and the erosion of the PCL-O films increased in parallel with a decrease in the PCL block length. The presence of the lipase inhibitors, paraoxon-ethyl and tetrahydrolipstatin delayed the weight loss of the PCL-O films. These results indicate that lipase was mainly responsible for the enzymatic erosion of the PCL-O films. In comparison, practically no weight loss of the PCL or the PCL-O films was observed in phosphate buffer (pH 7.4) (28 days incubation). The results demonstrate that the studied epsilon-caprolactone based poly(ester-amide)s are enzyme sensitive polymers whose erosion rate can be controlled by the PCL block length.

A functionalizable reverse thermal gel based on a polyurethane/PEG block copolymer

PubMed Central

Park, Daewon; Wu, Wei; Wang, Yadong

2010-01-01

Injectable reverse thermal gels have great potentials as biomaterials for tissue engineering and drug delivery. However, most existing gels lack functional groups that can be modified with biomolecules that can guide cell/material interactions. We created an amine-functionalized ABA block copolymer, poly(ethylene glycol)-poly(serinol hexamethylene urethane), or ESHU. This reverse thermal gel consists of a hydrophobic block (B): poly(serinol hexamethylene urethane) and a hydrophilic block (A): poly(ethylene glycol). The polymer was characterized by GPC, FTIR and 1H FTNMR. Rheological study demonstrated that ESHU solution in phosphate-buffered saline initiated phase transition at 32°C and reached maximum elastic modulus at 37°C. The in vitro degradation tests performed in PBS and cholesterol esterase solutions revealed that the polymer was hydrolyzable and the presence of cholesterol esterase greatly accelerated the hydrolysis. The in vitro cytotoxicity tests carried out using baboon smooth muscle cells demonstrated that ESHU had good cytocompatibility with cell viability indistinguishable from tissue culture treated polystyrene. Subcutaneous implantation in rats revealed well tolerated accurate inflammatory response with moderate ED-1 positive macrophages in the early stages, which largely resolved 4 weeks post-implantation. We functionalized ESHU with a hexapeptide, Ile-Lys-Val-Ala-Val-Ser (IKVAVS), which gelled rapidly at body temperature. We expect this new platform of functionalizable reverse thermal gels to provide versatile biomaterials in tissue engineering and regenerative medicine. PMID:20937526

Effect of intercostal nerve block combined with general anesthesia on the stress response in patients undergoing minimally invasive mitral valve surgery.

PubMed

Zhan, Yanping; Chen, Guo; Huang, Jian; Hou, Benchao; Liu, Weicheng; Chen, Shibiao

2017-10-01

The aim of the present study was to investigate the effect of intercostal nerve block combined with general anesthesia on the stress response and postoperative recovery in patients undergoing minimally invasive mitral valve surgery (MIMVS). A total of 30 patients scheduled for MIMVS were randomly divided into two groups (n=15 each): Group A, which received intercostal nerve block combined with general anesthesia and group B, which received general anesthesia alone. Intercostal nerve block in group A was performed with 0.5% ropivacaine from T3 to T7 prior to anesthesia induction. In each group, general anesthesia was induced using midazolam, sufentanil, propofol and vecuronium. Central venous blood samples were collected to determine the concentrations of cortisol, glucose, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) at the following time points: During central venous catheterization (T 1 ), 5 min prior to cardiopulmonary bypass (T 2 ), perioperative (T 3 ) and 24 h following surgery (T 4 ). Clinical data, including parameters of opioid (sufentanil) consumption, time of mechanical ventilation, duration of intensive care unit (ICU) stay, visual analog scale scores and any complications arising from intercostal nerve block, were recorded. Levels of cortisol, glucose, IL-6 and TNF-α in group A were significantly lower than those in group B at T 2 (all P<0.001; cortisol, P<0.05), T 3 (all P<0.001) and T 4 (all P<0.001; glucose, P<0.05), suggesting that intercostal nerve block combined with general anesthesia may inhibit the stress response to MIMVS. Additionally, intercostal nerve block combined with general anesthesia may significantly reduce sufentanil consumption (P<0.001), promote early tracheal extubation (P<0.001), shorten the duration of ICU stay (P<0.01) and attenuate postoperative pain (P<0.001), compared with general anesthesia alone. Thus, these results suggest that intercostal nerve block combined with general anesthesia conforms to the concept of rapid rehabilitation surgery and may be suitable for clinical practice.

Lyme Carditis Buried Beneath ST-Segment Elevations

PubMed Central

Umpierrez De Reguero, Adrian

2017-01-01

Lyme disease is caused by the spirochete Borrelia burgdorferi and is carried to human hosts by infected ticks. There are nearly 30,000 cases of Lyme disease reported to the CDC each year, with 3-4% of those cases reporting Lyme carditis. The most common manifestation of Lyme carditis is partial heart block following bacterial-induced inflammation of the conducting nodes. Here we report a 45-year-old gentleman that presented to the hospital with intense nonradiating chest pressure and tightness. Lab studies were remarkable for elevated troponins. EKG demonstrated normal sinus rhythm with mild ST elevations. Three weeks prior to hospital presentation, patient had gone hunting near Madison. One week prior to admission, he noticed an erythematous lesion on his right shoulder. Because of his constellation of history, arthralgias, and carditis, he was started on ceftriaxone to treat probable Lyme disease. This case illustrates the importance of thorough history taking and extensive physical examination when assessing a case of possible acute myocardial infarction. Because Lyme carditis is reversible, recognition of this syndrome in young patients, whether in the form of AV block, myocarditis, or acute myocardial ischemia, is critical to the initiation of appropriate antibiotics in order to prevent permanent heart block, or even death. PMID:28713599

Pleiotrophin as a Growth Factor and Therapeutic Target in Breast Cancer

DTIC Science & Technology

1997-10-01

novel phospholipase A2 related gene. Nucl Acid Res 21:135-143. 11. Gattoni-Celli, S., K . Kirsch, S. Kalled , and K . J. Isselbacher. 1986. Expression...clone (G11-F7) is enlarged. Genomic Southern blot probes (a,b,c) and restriction sites are shown (B=BamHI, H=HindIII, Sc=ScaI, K =KpnI). 10WJ 3fr 4&V...otherwise in 25 mM Tris pH8.3/200 mM glycine/20% methanol. The membrane was blocked in PBS (phospate-buffered saline )/0.1% Tween 20/5% powdered milk and

An electrochemical study of natural and chemically controlled eumelanin

NASA Astrophysics Data System (ADS)

Xu, Ri; Prontera, Carmela Tania; Di Mauro, Eduardo; Pezzella, Alessandro; Soavi, Francesca; Santato, Clara

2017-12-01

Eumelanin is the most common form of the pigment melanin in the human body, with functions including antioxidant behavior, metal chelation, and free radical scavenging. This biopigment is of interest for biologically derived batteries and supercapacitors. In this work, we characterized the voltammetric properties of chemically controlled eumelanins produced from 5,6-dihydroxyindole (DHI) and 5,6-dihydroxyindole-2-carboxylic acid (DHICA) building blocks, namely, DHI-melanin, DHICA-melanin, and natural eumelanin, extracted from the ink sac of cuttlefish, Sepia melanin. Eumelanin electrodes were studied for their cyclic voltammetric properties in acidic buffers including Na+, K+, NH4+, and Cu2+ ions.

Evidence that NMDA-dependent limbic neural plasticity in the right hemisphere mediates pharmacological stressor (FG-7142)-induced lasting increases in anxiety-like behavior. Study 2--The effects on behavior of block of NMDA receptors prior to injection of FG-7142.

PubMed

Adamec, R E

1998-01-01

The hypothesis that N-methyl-D-aspartate (NMDA) receptors mediate initiation of lasting behavioral changes induced by the anxiogenic beta-carboline, FG-7142, was supported in this study. Behavioral changes normally induced by FG-7142 were blocked when the competitive NMDA receptor blocker, 7-amino-phosphono-heptanoic acid, was given prior to administration of FG-7142. When cats were subsequently given FG-7142 alone, the drug produced lasting behavioral changes like those reported previously. Flumazenil, a benzodiazepine receptor antagonist, reversed an increase in defensiveness produced by FG-7142 alone, replicating previous findings. The data are consistent with the hypothesis that NMDA-dependent long-term potentiation in limbic pathways subserving defensive response to threat mediates lasting increases in defensiveness produced by FG-7142.

Digitized locksmith forensics: automated detection and segmentation of toolmarks on highly structured surfaces

NASA Astrophysics Data System (ADS)

Clausing, Eric; Vielhauer, Claus

2014-02-01

Locksmith forensics is an important area in crime scene forensics. Due to new optical, contactless, nanometer range sensing technology, such traces can be captured, digitized and analyzed more easily allowing a complete digital forensic investigation. In this paper we present a significantly improved approach for the detection and segmentation of toolmarks on surfaces of locking cylinder components (using the example of the locking cylinder component 'key pin') acquired by a 3D Confocal Laser Scanning Microscope. This improved approach is based on our prior work1 using a block-based classification approach with textural features. In this prior work1 we achieve a solid detection rate of 75-85% for the detection of toolmarks originating from illegal opening methods. Here, in this paper we improve, expand and fuse this prior approach with additional features from acquired surface topography data, color data and an image processing approach using adapted Gabor filters. In particular we are able of raising the detection and segmentation rates above 90% with our test set of 20 key pins with approximately 700 single toolmark traces of four different opening methods. We can provide a precise pixel- based segmentation as opposed to the rather imprecise segmentation of our prior block-based approach and as the use of the two additional data types (color and especially topography) require a specific pre-processing, we furthermore propose an adequate approach for this purpose.

Use of FEC coding to improve statistical multiplexing performance for video transport over ATM networks

NASA Astrophysics Data System (ADS)

Kurceren, Ragip; Modestino, James W.

1998-12-01

The use of forward error-control (FEC) coding, possibly in conjunction with ARQ techniques, has emerged as a promising approach for video transport over ATM networks for cell-loss recovery and/or bit error correction, such as might be required for wireless links. Although FEC provides cell-loss recovery capabilities it also introduces transmission overhead which can possibly cause additional cell losses. A methodology is described to maximize the number of video sources multiplexed at a given quality of service (QoS), measured in terms of decoded cell loss probability, using interlaced FEC codes. The transport channel is modelled as a block interference channel (BIC) and the multiplexer as single server, deterministic service, finite buffer supporting N users. Based upon an information-theoretic characterization of the BIC and large deviation bounds on the buffer overflow probability, the described methodology provides theoretically achievable upper limits on the number of sources multiplexed. Performance of specific coding techniques using interlaced nonbinary Reed-Solomon (RS) codes and binary rate-compatible punctured convolutional (RCPC) codes is illustrated.

An analog integrated circuit beamformer for high-frequency medical ultrasound imaging.

PubMed

Gurun, Gokce; Zahorian, Jaime S; Sisman, Alper; Karaman, Mustafa; Hasler, Paul E; Degertekin, F Levent

2012-10-01

We designed and fabricated a dynamic receive beamformer integrated circuit (IC) in 0.35-μm CMOS technology. This beamformer IC is suitable for integration with an annular array transducer for high-frequency (30-50 MHz) intravascular ultrasound (IVUS) imaging. The beamformer IC consists of receive preamplifiers, an analog dynamic delay-and-sum beamformer, and buffers for 8 receive channels. To form an analog dynamic delay line we designed an analog delay cell based on the current-mode first-order all-pass filter topology, as the basic building block. To increase the bandwidth of the delay cell, we explored an enhancement technique on the current mirrors. This technique improved the overall bandwidth of the delay line by a factor of 6. Each delay cell consumes 2.1-mW of power and is capable of generating a tunable time delay between 1.75 ns to 2.5 ns. We successfully integrated the fabricated beamformer IC with an 8-element annular array. Experimental test results demonstrated the desired buffering, preamplification and delaying capabilities of the beamformer.

Predictable and reliable ECG monitoring over IEEE 802.11 WLANs within a hospital.

PubMed

Park, Juyoung; Kang, Kyungtae

2014-09-01

Telecardiology provides mobility for patients who require constant electrocardiogram (ECG) monitoring. However, its safety is dependent on the predictability and robustness of data delivery, which must overcome errors in the wireless channel through which the ECG data are transmitted. We report here a framework that can be used to gauge the applicability of IEEE 802.11 wireless local area network (WLAN) technology to ECG monitoring systems in terms of delay constraints and transmission reliability. For this purpose, a medical-grade WLAN architecture achieved predictable delay through the combination of a medium access control mechanism based on the point coordination function provided by IEEE 802.11 and an error control scheme based on Reed-Solomon coding and block interleaving. The size of the jitter buffer needed was determined by this architecture to avoid service dropout caused by buffer underrun, through analysis of variations in transmission delay. Finally, we assessed this architecture in terms of service latency and reliability by modeling the transmission of uncompressed two-lead electrocardiogram data from the MIT-BIH Arrhythmia Database and highlight the applicability of this wireless technology to telecardiology.

Modelling the role of basement block rotation and strike-slip faulting on structural pattern in the cover units of fold-and-thrust belts

NASA Astrophysics Data System (ADS)

Koyi, Hemin; Nilfouroushan, Faramarz; Hessami, Khaled

2015-04-01

A series of scaled analogue models are run to study the degree of coupling between basement block kinematics and cover deformation. In these models, rigid basal blocks were rotated about vertical axis in a "bookshelf" fashion, which caused strike-slip faulting along the blocks and, to some degrees, in the overlying cover units of loose sand. Three different combinations of cover basement deformations are modeled; cover shortening prior to basement fault movement; basement fault movement prior to shortening of cover units; and simultaneous cover shortening with basement fault movement. Model results show that the effect of basement strike-slip faults depends on the timing of their reactivation during the orogenic process. Pre- and syn-orogen basement strike-slip faults have a significant impact on the structural pattern of the cover units, whereas post-orogenic basement strike-slip faults have less influence on the thickened hinterland of the overlying fold-and-thrust belt. The interaction of basement faulting and cover shortening results in formation of rhomb features. In models with pre- and syn-orogen basement strike-slip faults, rhomb-shaped cover blocks develop as a result of shortening of the overlying cover during basement strike-slip faulting. These rhombic blocks, which have resemblance to flower structures, differ in kinematics, genesis and structural extent. They are bounded by strike-slip faults on two opposite sides and thrusts on the other two sides. In the models, rhomb-shaped cover blocks develop as a result of shortening of the overlying cover during basement strke-slip faulting. Such rhomb features are recognized in the Alborz and Zagros fold-and-thrust belts where cover units are shortened simultaneously with strike-slip faulting in the basement. Model results are also compared with geodetic results obtained from combination of all available GPS velocities in the Zagros and Alborz FTBs. Geodetic results indicate domains of clockwise and anticlockwise rotation in these two FTBs. The typical pattern of structures and their spatial distributions are used to suggest clockwise block rotation of basement blocks about vertical axes and their associated strike-slip faulting in both west-central Alborz and the southeastern part of the Zagros fold-and-thrust belt.

Design and development of cell queuing, processing, and scheduling modules for the iPOINT input-buffered ATM testbed

NASA Astrophysics Data System (ADS)

Duan, Haoran

1997-12-01

This dissertation presents the concepts, principles, performance, and implementation of input queuing and cell-scheduling modules for the Illinois Pulsar-based Optical INTerconnect (iPOINT) input-buffered Asynchronous Transfer Mode (ATM) testbed. Input queuing (IQ) ATM switches are well suited to meet the requirements of current and future ultra-broadband ATM networks. The IQ structure imposes minimum memory bandwidth requirements for cell buffering, tolerates bursty traffic, and utilizes memory efficiently for multicast traffic. The lack of efficient cell queuing and scheduling solutions has been a major barrier to build high-performance, scalable IQ-based ATM switches. This dissertation proposes a new Three-Dimensional Queue (3DQ) and a novel Matrix Unit Cell Scheduler (MUCS) to remove this barrier. 3DQ uses a linked-list architecture based on Synchronous Random Access Memory (SRAM) to combine the individual advantages of per-virtual-circuit (per-VC) queuing, priority queuing, and N-destination queuing. It avoids Head of Line (HOL) blocking and provides per-VC Quality of Service (QoS) enforcement mechanisms. Computer simulation results verify the QoS capabilities of 3DQ. For multicast traffic, 3DQ provides efficient usage of cell buffering memory by storing multicast cells only once. Further, the multicast mechanism of 3DQ prevents a congested destination port from blocking other less- loaded ports. The 3DQ principle has been prototyped in the Illinois Input Queue (iiQueue) module. Using Field Programmable Gate Array (FPGA) devices, SRAM modules, and integrated on a Printed Circuit Board (PCB), iiQueue can process incoming traffic at 800 Mb/s. Using faster circuit technology, the same design is expected to operate at the OC-48 rate (2.5 Gb/s). MUCS resolves the output contention by evaluating the weight index of each candidate and selecting the heaviest. It achieves near-optimal scheduling and has a very short response time. The algorithm originates from a heuristic strategy that leads to 'socially optimal' solutions, yielding a maximum number of contention-free cells being scheduled. A novel mixed digital-analog circuit has been designed to implement the MUCS core functionality. The MUCS circuit maps the cell scheduling computation to the capacitor charging and discharging procedures that are conducted fully in parallel. The design has a uniform circuit structure, low interconnect counts, and low chip I/O counts. Using 2 μm CMOS technology, the design operates on a 100 MHz clock and finds a near-optimal solution within a linear processing time. The circuit has been verified at the transistor level by HSPICE simulation. During this research, a five-port IQ-based optoelectronic iPOINT ATM switch has been developed and demonstrated. It has been fully functional with an aggregate throughput of 800 Mb/s. The second-generation IQ-based switch is currently under development. Equipped with iiQueue modules and MUCS module, the new switch system will deliver a multi-gigabit aggregate throughput, eliminate HOL blocking, provide per-VC QoS, and achieve near-100% link bandwidth utilization. Complete documentation of input modules and trunk module for the existing testbed, and complete documentation of 3DQ, iiQueue, and MUCS for the second-generation testbed are given in this dissertation.

Effect of two mouthwashes on salivary ph.

PubMed

Belardinelli, Paola A; Morelatto, Rosana A; Benavidez, Tomás E; Baruzzi, Ana M; López de Blanc, Silvia A

2014-01-01

To analyze the effect of two mouthwashes on salivary pH and correlate it with age, buffer capacity and saliva flow rate in healthy volunteers, a crossover phase IV clinical study involving three age-based groups was designed. Two commercial mouthwashes (MW), Cool Mint ListerineR (MWa) and Periobacter R (MWb) were used. The unstimulated saliva of each individual was first characterized by measuring flow rate, pH, and buffer capacity. Salivary pH was evaluated before rinsing with a given MW, immediately after rinsing, 5 minutes later, and then every 10 min (at 15, 25, 35 min) until the baseline pH was recovered. Paired t-test, ANOVA with a randomized block design, and Pearson correlation tests were used. Averages were 0.63 mL/min, 7.06, and 0.87 for flow rate, pH, and buffer capacity, respectively. An immediate significant increase in salivary pH was observed after rinsing, reaching average values of 7.24 (MWb) and 7.30 (MWa), which declined to an almost stable value 15 minutes. The great increase in salivary pH, after MW use shows that saliva is a dynamic system, and that the organism is capable of responding to a stimulus with changes in its composition. It is thus evident that pH of the external agent alone is not a good indicator for its erosive potential because biological systems tend to neutralize it. The results of this study enhance the importance of in vivo measurements and reinforce the concept of the protective action of saliva.

Efficient osmolyte-based procedure to increase expression level and solubility of infectious hematopoietic necrosis virus (IHNV) nucleoprotein in E. coli.

PubMed

Mohammadinezhad, Rezvan; Farahmand, Hamid; Jalali, Seyed Amir Hossein; Mirvaghefi, Alireza

2018-05-01

The nucleoprotein of infectious hematopoietic necrosis virus (IHNV) is considered as the main target antigen for detection of IHNV infection in salmonid fish. This study aimed at improving the expression and solubility of IHNV nucleoprotein (IHNV-NP) in E. coli expression system. The effects of several expression strategies including host strain type, protein expression temperature, heat-shock treatment prior to protein induction, and additives in the growth medium and in the cell lysis buffer were examined. Results showed that bacterial strain type had a great impact on protein expression level, whereas it was not effective in preventing protein aggregation. Production of soluble IHNV-NP was proportionally increased with decreased incubation temperature. Heat-shock treatment prior to protein induction did not change the percent of solubility. For cells grown at low temperature, the presence of additives in the lysis buffer enhanced the solubility of IHNV-NP up to 24%. The highest yield of soluble protein was obtained via incorporation of osmolytes in the growth medium of cells exposed to a mild salt stress, in the following order: sucrose > sorbitol > glycerol > glycine. Soluble protein obtained by the optimized condition was efficiently purified in high yield and successfully detected by two monoclonal antibodies in a sandwich ELISA. Taken together, a combination of proper host strain, low-temperature expression, and timely application of osmolytes in the growth medium provided sufficient quantities of soluble recombinant IHNV-NP that has the potential to be used for diagnostic purposes.

A role for midline and intralaminar thalamus in the associative blocking of Pavlovian fear conditioning.

PubMed

Sengupta, Auntora; McNally, Gavan P

2014-01-01

Fear learning occurs in response to positive prediction error, when the expected outcome of a conditioning trial exceeds that predicted by the conditioned stimuli present. This role for error in Pavlovian association formation is best exemplified by the phenomenon of associative blocking, whereby prior fear conditioning of conditioned stimulus (CS) A is able to prevent learning to CSB when they are conditioned in compound. The midline and intralaminar thalamic nuclei (MIT) are well-placed to contribute to fear prediction error because they receive extensive projections from the midbrain periaqueductal gray-which has a key role in fear prediction error-and project extensively to prefrontal cortex and amygdala. Here we used an associative blocking design to study the role of MIT in fear learning. In Stage I rats were trained to fear CSA via pairings with shock. In Stage II rats received compound fear conditioning of CSAB paired with shock. On test, rats that received Stage I training expressed less fear to CSB relative to control rats that did not receive this training. Microinjection of bupivacaine into MIT prior to Stage II training had no effect on the expression of fear during Stage II and had no effect on fear learning in controls, but prevented associative blocking and so enabled fear learning to CSB. These results show an important role for MIT in predictive fear learning and are discussed with reference to previous findings implicating the midline and posterior intralaminar thalamus in fear learning and fear responding.

Processes and mechanisms of persistent extreme precipitation events in East China

NASA Astrophysics Data System (ADS)

Zhai, Panmao; Chen, Yang

2014-11-01

This study mainly presents recent progresses on persistent extreme precipitation events (PEPEs) in East China. A definition focusing both persistence and extremity of daily precipitation is firstly proposed. An identification method for quasi-stationary regional PEPEs is then designed. By utilizing the identified PEPEs in East China, typical circulation configurations from the lower to the upper troposphere are confirmed, followed by investigations of synoptic precursors for key components with lead time of 1-2 weeks. Two characteristic circulation patterns responsible for PEPEs in East China are identified: a double blocking high type and a single blocking high type. They may account for occurrence of nearly 80% PEPEs during last 60 years. For double blocking high type, about two weeks prior to PEPEs, two blockings developed and progressed towards the Ural Mountains and the Sea of Okhotsk, respectively. A northwestward progressive anomalous anticyclone conveying abundant moisture and eastward-extended South Asia High favoring divergence can be detected about one week in advance. A dominant summertime teleconnection over East Asia, East Asia/ Pacific (EAP) pattern, is deemed as another typical regime inducing PEPEs in the East China. Key elements of the EAP pattern initiated westward movement since one week prior to PEPEs. Eastward energy dispersion and poleward energy dispersion contributed to early development and subsequent maintenance of this teleconnection pattern, respectively. These typical circulation patterns and significant precursors may offer local forecasters some useful clues in identifying and predicting such high-impact precipitation events about 1-2 weeks in advance.

Polyelectrolyte Complex Optimization for Macrophage Delivery of Redox Enzyme Nanoparticles

PubMed Central

Zhao, Yuling; Haney, Matthew J.; Klyachko, Natalia L.; Li, Shu; Booth, Stephanie L.; Higginbotham, Sheila M.; Jones, Jocelyn; Zimmerman, Matthew C.; Mosley, R. Lee; Kabanov, Alexander V.; Gendelman, Howard E.; Batrakova, Elena V.

2011-01-01

Background We posit that cell-mediated drug delivery can improve transport of therapeutic enzymes to the brain and decrease inflammation and neurodegeneration induced during Parkinson’s disease. Our prior work demonstrated that macrophages loaded with nanoformulated catalase (“nanozyme”) protect the nigrostriatum in a murine model of Parkinson’s disease. Packaging of catalase into block ionomer complex with a synthetic polyelectrolyte block copolymers protects the enzyme degradation in macrophages. Methods We examined relationships between the composition and structure of block ionomer complexes, their physicochemical characteristics, and loadings, release rates, and catalase activity in bone marrow-derived macrophages. Results Formation of block-ionomer complexes resulted in improved aggregation stability. Block ionomer complexes with ε-polylisine, and poly-L-glutamic acid -poly(ethylene glycol) demonstrated the least cytotoxicity and high loading and release rates, however, did not efficiently protect catalase inside macrophages. Conclusion nanozymes with polyethyleneimine- and poly(L-lysine)10-poly(ethylene glycol) provided the best protection of enzymatic activity for cell-mediated drug delivery. PMID:21182416

Determining informative priors for cognitive models.

PubMed

Lee, Michael D; Vanpaemel, Wolf

2018-02-01

The development of cognitive models involves the creative scientific formalization of assumptions, based on theory, observation, and other relevant information. In the Bayesian approach to implementing, testing, and using cognitive models, assumptions can influence both the likelihood function of the model, usually corresponding to assumptions about psychological processes, and the prior distribution over model parameters, usually corresponding to assumptions about the psychological variables that influence those processes. The specification of the prior is unique to the Bayesian context, but often raises concerns that lead to the use of vague or non-informative priors in cognitive modeling. Sometimes the concerns stem from philosophical objections, but more often practical difficulties with how priors should be determined are the stumbling block. We survey several sources of information that can help to specify priors for cognitive models, discuss some of the methods by which this information can be formalized in a prior distribution, and identify a number of benefits of including informative priors in cognitive modeling. Our discussion is based on three illustrative cognitive models, involving memory retention, categorization, and decision making.

A Cenozoic tectonic model for Southeast Asia - microplates and basins

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

Maher, K.A.

1995-04-01

A computer-assisted Cenozoic tectonic model was built for Southeast Asia and used to construct 23 base maps, 2 to 6 million years apart. This close temporal spacing was necessary to constrain all the local geometric shifts in a consistent and geologically feasible fashion. More than a hundred individual blocks were required to adequately treat Cenozoic microplate processes at a basic level. The reconstructions show tectonic evolution to be characterized by long periods of gradual evolution, interrupted by brief, widespread episodes of reorganization in fundamental plate geometries and kinematics. These episodes are triggered by major collisions, or by accumulation of smallermore » changes. The model takes into account difficulties inherent in the region. The Pacific and Indo-Australian plates and their predecessors have driven westward and northward since the late Paleozoic, towards each other and the relatively stationary backstop of Asia. Southeast Asia is therefore the result of a long-lived, complex process of convergent tectonics, making it difficult to reconstruct tectonic evolution as much of the continental margin and sea floor spreading record was erased. In addition, the region has been dominated by small-scale microplate processes with short time scales and internal deformation, taking place in rapidly evolving and more ductile buffer zones between the major rigid plate systems. These plate interaction zones have taken up much of the relative motion between the major plates. Relatively ephemeral crustal blocks appear and die within the buffer zones, or accrete to and disperse from the margins of the major plate systems. However, such microplate evolution is the dominant factor in Cenozoic basin evolution. This detailed testonic model aids in comprehension and prediction of basin development, regional hydrocarbon habitat, and petroleum systems.« less

Bacoside-A, an Indian Traditional-Medicine Substance, Inhibits β-Amyloid Cytotoxicity, Fibrillation, and Membrane Interactions.

PubMed

Malishev, Ravit; Shaham-Niv, Shira; Nandi, Sukhendu; Kolusheva, Sofiya; Gazit, Ehud; Jelinek, Raz

2017-04-19

Bacoside-A, a family of compounds extracted from the Bacopa monniera plant, is a folk-medicinal substance believed to exhibit therapeutic properties, particularly enhancing cognitive functions and improving memory. We show that bacoside-A exerted significant inhibitory effects upon cytotoxicity, fibrillation, and particularly membrane interactions of amyloid-beta (1-42) (Aβ42), the peptide playing a prominent role in Alzeheimer's disease progression and toxicity. Specifically, preincubation of bacoside-A with Aβ42 significantly reduced cell toxicity and inhibited fibril formation both in buffer solution and, more significantly, in the presence of membrane vesicles. In parallel, spectroscopic and microscopic analyses reveal that bacoside-A blocked membrane interactions of Aβ42, while formation of Aβ42 oligomers was not disrupted. These interesting phenomena suggest that inhibition of Aβ42 oligomer assembly into mature fibrils, and blocking membrane interactions of the oligomers are likely the underlying factors for ameliorating amyloid toxicity by bacoside-A and its putative physiological benefits.

Data compression: The end-to-end information systems perspective for NASA space science missions

NASA Technical Reports Server (NTRS)

Tai, Wallace

1991-01-01

The unique characteristics of compressed data have important implications to the design of space science data systems, science applications, and data compression techniques. The sequential nature or data dependence between each of the sample values within a block of compressed data introduces an error multiplication or propagation factor which compounds the effects of communication errors. The data communication characteristics of the onboard data acquisition, storage, and telecommunication channels may influence the size of the compressed blocks and the frequency of included re-initialization points. The organization of the compressed data are continually changing depending on the entropy of the input data. This also results in a variable output rate from the instrument which may require buffering to interface with the spacecraft data system. On the ground, there exist key tradeoff issues associated with the distribution and management of the science data products when data compression techniques are applied in order to alleviate the constraints imposed by ground communication bandwidth and data storage capacity.

Reserve Component Attitude Study Wave V. 1982 Tracking Study. Volume 1. Major Findings and Implications.

DTIC Science & Technology

1983-05-01

by block number) FIELD GROUP SUB-GROUP Military/Manpower/Reserve Force/Recruiting Market/ 05 09 Research / Non -prior service/Prior Service/Male/Female...7 RD-R149 32 RESERVE COMPONENT ATTITUDE STUDY WAVE V 1982 TRACKING L/~STUDY VOLUME ± MAJO..(U) AS OCIATES FOR RESEARCH INBEHAVIOR INC PHILADELPHIA PA... RESEARCH IN BEHAVIOR, INC.) PHILADELPHIA, PENNSYLVANIA .2A~* -ION4 STA~EMEwzw AK Apploved fat public telecoo, DiatiLi]tion Unlimited -- .- .. ..i- -- k

Identification and Characterization of Intercritical Heat-Affected Zone in As-Welded Grade 91 Weldment

NASA Astrophysics Data System (ADS)

Wang, Yiyu; Kannan, Rangasayee; Li, Leijun

2016-12-01

A metallurgical method is proposed for locating the intercritical heat-affected zone in the as-welded Grade 91 steel. New austenitic grains, preferentially formed along the original prior austenite grain boundaries, are characterized to contain finer M23C6 carbides and higher strain levels than the original prior austenite grains. Kurdjumov-Sachs Group 1 variant pairs, with a low misorientation of 7 deg within a martensitic block, are identified as the dominant variants in the new PAGs.

[Perioperative management of a patient with myotonic dystrophy developing the cardiac symptoms initially prior to the neuromuscular symptoms].

PubMed

Wake, M; Matsushita, M; Aono, H; Matsumoto, M; Kohri, Y

1994-08-01

The authors anesthetized a 48-year-old woman with endometrial cancer and a large ovarian cyst. She developed cardiac failure initially followed by the sick sinus syndrome and A-V block from hypertrophic cardiomyopathy, prior to neuromuscular symptoms. Epidural anesthesia assisted by general anesthesia was carried out safely without intravenous administration of any muscle relaxants. From this experience, it is considered that epidural anesthesia assisted with some other proper methods is suitable for surgery of lower abdomen.

Fluorescent single walled nanotube/silica composite materials

DOEpatents

Dattelbaum, Andrew M.; Gupta, Gautam; Duque, Juan G.; Doorn, Stephen K.; Hamilton, Christopher E.; DeFriend Obrey, Kimberly A.

2013-03-12

Fluorescent composites of surfactant-wrapped single-walled carbon nanotubes (SWNTs) were prepared by exposing suspensions of surfactant-wrapped carbon nanotubes to tetramethylorthosilicate (TMOS) vapor. Sodium deoxycholate (DOC) and sodium dodecylsulphate (SDS) were the surfactants. No loss in emission intensity was observed when the suspension of DOC-wrapped SWNTs were exposed to the TMOS vapors, but about a 50% decrease in the emission signal was observed from the SDS-wrapped SWNTs nanotubes. The decrease in emission was minimal by buffering the SDS/SWNT suspension prior to forming the composite. Fluorescent xerogels were prepared by adding glycerol to the SWNT suspensions prior to TMOS vapor exposure, followed by drying the gels. Fluorescent aerogels were prepared by replacing water in the gels with methanol and then exposing them to supercritical fluid drying conditions. The aerogels can be used for gas sensing.

31 CFR 545.409 - Payments from blocked accounts to U.S. exporters and for other obligations prohibited.

Code of Federal Regulations, 2010 CFR

2010-07-01

... to pay obligations to U.S. persons or other persons, including payment for goods, software, technology, or services exported prior to the effective date, except as authorized pursuant to this part. ...

Evaluation of methods to reduce background using the Python-based ELISA_QC program.

PubMed

Webster, Rose P; Cohen, Cinder F; Saeed, Fatima O; Wetzel, Hanna N; Ball, William J; Kirley, Terence L; Norman, Andrew B

2018-05-01

Almost all immunological approaches [immunohistochemistry, enzyme-linked immunosorbent assay (ELISA), Western blot], that are used to quantitate specific proteins have had to address high backgrounds due to non-specific reactivity. We report here for the first time a quantitative comparison of methods for reduction of the background of commercial biotinylated antibodies using the Python-based ELISA_QC program. This is demonstrated using a recombinant humanized anti-cocaine monoclonal antibody. Several approaches, such as adjustment of the incubation time and the concentration of blocking agent, as well as the dilution of secondary antibodies, have been explored to address this issue. In this report, systematic comparisons of two different methods, contrasted with other more traditional methods to address this problem are provided. Addition of heparin (HP) at 1 μg/ml to the wash buffer prior to addition of the secondary biotinylated antibody reduced the elevated background absorbance values (from a mean of 0.313 ± 0.015 to 0.137 ± 0.002). A novel immunodepletion (ID) method also reduced the background (from a mean of 0.331 ± 0.010 to 0.146 ± 0.013). Overall, the ID method generated more similar results at each concentration of the ELISA standard curve to that using the standard lot 1 than the HP method, as analyzed by the Python-based ELISA_QC program. We conclude that the ID method, while more laborious, provides the best solution to resolve the high background seen with specific lots of biotinylated secondary antibody. Copyright © 2018. Published by Elsevier B.V.

Galanin Mediates Features of Neural and Behavioral Stress Resilience Afforded by Exercise

PubMed Central

Sciolino, N. R.; Smith, J.M.; Stranahan, A.M.; Freeman, K.G.; Edwards, G. L.; Weinshenker, D.; Holmes, P.V.

2014-01-01

Exercise promotes resilience to stress and increases galanin in the locus coeruleus (LC), but the question of whether changes in galanin signaling mediate the stress-buffering effects of exercise has never been addressed. To test the contributions of galanin to stress resilience, male Sprague Dawley rats received intracerebroventricular (ICV) cannulation for drug delivery and frontocortical cannulation for microdialysis, and were housed with or without a running wheel for 21d. Rats were acutely injected with vehicle or the galanin receptor antagonist M40 and exposed to a single session of either footshock or no stress. Other groups received galanin, the galanin receptor antagonist M40, or vehicle chronically for 21d prior to the stress session. Microdialysis sampling occurred during stress exposure and anxiety-related behavior was measured on the following day in the elevated plus maze. Dendritic spines were visualized by Golgi impregnation in medial prefrontal cortex (mPFC) pyramidal neurons and quantified. Exercise increased galanin levels in the LC. Under non-stressed conditions, anxiety-related behavior and dopamine levels were comparable between exercised and sedentary rats. In contrast, exposure to stress reduced open arm exploration in sedentary rats but not in exercise rats or those treated chronically with ICV galanin, indicating improved resilience. Both exercise and chronic, ICV galanin prevented the increased dopamine overflow and loss of dendritic spines observed after stress in sedentary rats. Chronic, but not acute M40 administration blocked the resilience-promoting effects of exercise. The results indicate that increased galanin levels promote features of resilience at both behavioral and neural levels. PMID:25301278

Effects of TiO2 electron blocking layer on photovoltaic performance of photo-electrochemical cell

NASA Astrophysics Data System (ADS)

Bin, Jae-Wook; Kim, Doo-Hwan; Sung, Youl-Moon; Park, Min-Woo

2014-06-01

Dye-sensitized solar cells (DSCs) have used transparent conductive Fluorine-doped SnO2 (FTO) glass/porous TiO2 layer attached using dye molecules/electrolytes (I-/I3-)/Platinium-coated FTO glass configuration. In this work, prior to the coating of nanoporous TiO2 layer on FTO glass, a dense layer of TiO2 film with a thickness of less than ∼100 nm was deposited directly onto the FTO as an electron blocking layer by radio frequency (RF) magnetron sputtering. Under 100 mW/cm2 illumination at AM 1.5, the energy conversion efficiency (η) of the prepared DSC with electron blocking layer of 80 nm thickness was 6.9% (Voc = 0.67 V, Jsc = 12.18 mA/cm2, ff = 0.63), which is increased by 1.3% compared to the typical cell without electron blocking layer.

Density-dependent regulation of population size in colonial breeders: Allee and buffer effects in the migratory Montagu's harrier.

PubMed

Soutullo, Alvaro; Limiñana, Rubén; Urios, Vicente; Surroca, Martín; A Gill, Jennifer

2006-09-01

Expanding populations offer an opportunity to uncover the processes driving spatial variation in distribution and abundance. Individual settlement decisions will be influenced by the availability and relative quality of patches, and by how these respond to changes in conspecific density. For example, conspecific presence can alter patch suitability through reductions in resource availability or territorial exclusion, leading to buffer effect patterns of disproportionate population expansion into poorer quality areas. However, conspecific presence can also enhance patch suitability through Allee effect processes, such as transmission of information about resources or improved predator detection and deterrence. Here, we explore the factors underlying the settlement pattern of a growing population of Montagu's harriers (Circus pygargus) in Spain. The population increased exponentially between 1981 and 2001, but stabilised between 2001 and 2004. This population increase occurred alongside a remarkable spatial expansion, with novel site use occurring prior to maximum densities in occupied sites being reached. However, no temporal trends in fecundity were observed and, within sites, average fecundity did not decline with increasing density. Across the population, variance in productivity did increase with population size, suggesting a complex pattern of density-dependent costs and benefits. We suggest that both Allee and buffer effects are operating in this system, with the benefits of conspecific presence counteracting density-dependent declines in resource availability or quality.

Tris-base buffer: a promising new inhibitor for cancer progression and metastasis.

PubMed

Ibrahim-Hashim, Arig; Abrahams, Dominique; Enriquez-Navas, Pedro M; Luddy, Kim; Gatenby, Robert A; Gillies, Robert J

2017-07-01

Neutralizing tumor external acidity with oral buffers has proven effective for the prevention and inhibition of metastasis in several cancer mouse models. Solid tumors are highly acidic as a result of high glycolysis combined with an inadequate blood supply. Our prior work has shown that sodium bicarbonate, imidazole, and free-base (but not protonated) lysine are effective in reducing tumor progression and metastasis. However, a concern in translating these results to clinic has been the presence of counter ions and their potential undesirable side effects (e.g., hypernatremia). In this work, we investigate tris(hydroxymethyl)aminomethane, (THAM or Tris), a primary amine with no counter ion, for its effects on metastasis and progression in prostate and pancreatic cancer in vivo models using MRI and bioluminescence imaging. At an ad lib concentration of 200 mmol/L, Tris effectively inhibited metastasis in both models and furthermore led to a decrease in the expression of the major glucose transporter, GLUT-1. Our results also showed that Tris-base buffer (pH 8.4) had no overt toxicity to C3H mice even at higher doses (400 mmol/L). In conclusion, we have developed a novel therapeutic approach to manipulate tumor extracellular pH (pHe) that could be readily adapted to a clinical trial. © 2017 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

The efficacy of techniques for the disinfection of artificial sub-surface dentinal caries lesions and their effect on demineralization and remineralization in vitro.

PubMed

Preston, K P; Higham, S M; Smith, P W

2007-06-01

The efficacy of three techniques for the disinfection of artificial sub-surface root caries lesions and their response to subsequent episodes of de- and remineralization was investigated quantitatively in vitro. Sub-surface dentinal lesions (n=20), cut into four experimental blocks and deliberately contaminated with Streptococcus mutans, were subject to either steam autoclaving (121 degrees C, 5min), gamma irradiation (4100Gy), immersion in 0.1% (w/v) thymol-distilled water solution (24h) or reserved as a control. Next, the lesions were incubated aerobically in sterile nutrient broth for 24h at 37 degrees C and resultant cultures plated onto blood agar and neutralisation agar. Ten blocks from each experimental group were then immersed in an acidic buffer solution or exposed to artificial saliva for 5 days. Baseline changes in the mineral content and distribution of the lesions were assessed by transverse microradiography (TMR). Micro-organisms were recovered from each control block and one block treated by gamma irradiation. Steam autoclaving and immersion in a thymol solution significantly decreased (p<0.05) the amount of mineral lost from the body of lesions subject to a further acid challenge. Mineral ion uptake by lesions exposed to artificial saliva was significantly increased (p<0.05) through disinfection by steam autoclaving. Gamma irradiation proved the most acceptable method for the disinfection of sub-surface root dentine lesions having the least adverse effect on demineralization and remineralization.

Nonalcoholic fatty liver disease is associated with an increased risk of heart block in hospitalized patients with type 2 diabetes mellitus.

PubMed

Mantovani, Alessandro; Rigolon, Riccardo; Pichiri, Isabella; Bonapace, Stefano; Morani, Giovanni; Zoppini, Giacomo; Bonora, Enzo; Targher, Giovanni

2017-01-01

Recent studies suggested that nonalcoholic fatty liver disease (NAFLD) is associated with an increased risk of cardiac tachyarrhythmias (mainly atrial fibrillation) in patients with and without type 2 diabetes mellitus. The aim of this study was to examine whether an association also exists between NAFLD and heart block. We have retrospectively evaluated a hospital-based cohort of 751 patients with type 2 diabetes discharged from our Division of Diabetes and Endocrinology during years 2007-2014. Standard electrocardiograms were performed on all patients. Diagnosis of NAFLD was based on ultrasonography, whereas the severity of advanced hepatic fibrosis was based on the fibrosis (FIB)-4 score and other non-invasive fibrosis markers. Overall, 524 (69.8%) patients had NAFLD and 202 (26.9%) had heart block (defined as at least one block among first-degree atrio-ventricular block, second-degree block, third-degree block, left bundle branch block, right bundle branch block, left anterior hemi-block or left posterior hemi-block) on electrocardiograms. Patients with NAFLD had a remarkably higher prevalence of any persistent heart block than those without NAFLD (31.3% vs. 16.7%, p<0.001); this prevalence was particularly increased among those with higher FIB-4 score. NAFLD was associated with a threefold increased risk of prevalent heart block (adjusted-odds ratio 3.04, 95% CI 1.81-5.10), independently of age, sex, hypertension, prior ischemic heart disease, hemoglobin A1c, microvascular complication status, use of medications and other potentially confounding factors. In conclusion, this is the largest cross-sectional study to show that NAFLD and its severity are independently associated with an increased risk of prevalent heart block in hospitalized patients with type 2 diabetes.

Sandblasting may damage the surface of composite CAD-CAM blocks.

PubMed

Yoshihara, Kumiko; Nagaoka, Noriyuki; Maruo, Yukinori; Nishigawa, Goro; Irie, Masao; Yoshida, Yasuhiro; Van Meerbeek, Bart

2017-03-01

CAD-CAM blocks to fabricate semi-direct and indirect restorations are available in different sorts of ceramics as well as composite. In order to bond restorations prepared out of composite blocks into tooth cavities, it is recommended to gently sandblast the surface prior to the application of a primer/adhesive. Today, the effect of sandblasting composite block surfaces has not thoroughly been investigated. In this study, the ultra-structure of composite CAD-CAM blocks was investigated with special attention to the effect of sandblasting on the surface topography and of silanization on the bonding performance. Five different composite CAD-CAM blocks were involved. We correlatively investigated their structural and chemical composition using X-ray diffraction (XRD), energy dispersion spectroscopy (EDS), scanning electron microscopy (SEM) and (scanning) transmission electron microscopy ((S)TEM). The effect of sandblasting was also imaged in cross-section and at the interface with composite cement. Finally, we measured the shear bond strength to the sandblasted block surface with and without silanization. All composite blocks revealed a different ultra-structure. Sandblasting increased surface roughness and resulted in an irregular surface with some filler exposure. Sandblasting also damaged the surface. When the sandblasted composite blocks were silanized, superior bonding receptiveness in terms of higher bond strength was achieved except for Shofu Block HC. Sandblasting followed by silanization improved the bond strength to composite CAD-CAM blocks. However, sandblasting may also damage the composite CAD-CAM block surface. For the composite CAD-CAM block Shofu Block HC, the damage was so severe that silanization did not improve bond strength. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Phosphorus Concentrations in Sequentially Fractionated Soil Samples as Affected by Digestion Methods

PubMed Central

do Nascimento, Carlos A. C.; Pagliari, Paulo H.; Schmitt, Djalma; He, Zhongqi; Waldrip, Heidi

2015-01-01

Sequential fractionation has helped improving our understanding of the lability and bioavailability of P in soil. Nevertheless, there have been no reports on how manipulation of the different fractions prior to analyses affects the total P (TP) concentrations measured. This study investigated the effects of sample digestion, filtration, and acidification on the TP concentrations determined by ICP-OES in 20 soil samples. Total P in extracts were either determined without digestion by ICP-OES, or ICP-OES following block digestion, or autoclave digestion. The effects of sample filtration, and acidification on undigested alkaline extracts prior to ICP-OES were also evaluated. Results showed that, TP concentrations were greatest in the block-digested extracts, though the variability introduced by the block-digestion was the highest. Acidification of NaHCO3 extracts resulted in lower TP concentrations, while acidification of NaOH randomly increased or decreased TP concentrations. The precision observed with ICP-OES of undigested extracts suggests this should be the preferred method for TP determination in sequentially extracted samples. Thus, observations reported in this work would be helpful in appropriate sample handling for P determination, thereby improving the precision of P determination. The results are also useful for literature data comparison and discussion when there are differences in sample treatments. PMID:26647644

Macromolecular Colloids of Diblock Poly(amino acids) That Bind Insulin.

PubMed

Constancis; Meyrueix; Bryson; Huille; Grosselin; Gulik-Krzywicki; Soula

1999-09-15

The diblock polymer poly(l-leucine-block-l-glutamate), bLE, was synthesized by acid hydrolysis of the ester poly(l-leucine-block-l-methyl glutamate). During the hydrolysis reaction the leucine block precipitates from the reaction mixture, forming nanosized particulate structures. These particles can be purified and further suspended in water or in 0.15 M phosphate saline buffer (PBS) to give stable, colloidal dispersions. TEM analysis shows the predominant particle form to be that of platelets with a diameter of 200 nm. Smaller cylindrical or spherical particles form a relatively minor fraction of the sample. After fractionation, analysis shows the platelets to be compositionally rich in leucine, while the spheres are glutamate-rich. (1)H NMR, CD, and X-ray diffraction indicate that the core of the platelets is composed of crystalline, helical leucine segments. The poly(l-glutamate) polyelectrolyte brush extending out from the two faces of the disk stabilizes individual particles from flocculation. At pH 7.4, the nanoparticles (platelets and cylinders) spontaneously adsorb proteins, such as insulin, directly from solution. Partial desorption of the protein in its native configuration can be induced by simple dilution. The reversibility of the insulin-nanoparticle complex is the basis for a potential new delivery system. Copyright 1999 Academic Press.

Regenerative memory in time-delayed neuromorphic photonic resonators

NASA Astrophysics Data System (ADS)

Romeira, B.; Avó, R.; Figueiredo, José M. L.; Barland, S.; Javaloyes, J.

2016-01-01

We investigate a photonic regenerative memory based upon a neuromorphic oscillator with a delayed self-feedback (autaptic) connection. We disclose the existence of a unique temporal response characteristic of localized structures enabling an ideal support for bits in an optical buffer memory for storage and reshaping of data information. We link our experimental implementation, based upon a nanoscale nonlinear resonant tunneling diode driving a laser, to the paradigm of neuronal activity, the FitzHugh-Nagumo model with delayed feedback. This proof-of-concept photonic regenerative memory might constitute a building block for a new class of neuron-inspired photonic memories that can handle high bit-rate optical signals.

Change in the temporal coordination of the finger joints with ulnar nerve block during different power grips analyzed with a sensor glove.

PubMed

Wachter, N J; Mentzel, M; Häderer, C; Krischak, G D; Gülke, J

2018-02-01

Ulnar nerve injuries can cause deficient hand movement patterns. Their assessment is important for diagnosis and rehabilitation in hand surgery cases. The purpose of this study was to quantify the changes in temporal coordination of the finger joints during different power grips with an ulnar nerve block by means of a sensor glove. In 21 healthy subjects, the onset and end of the active flexion of the 14 finger joints when gripping objects of different diameters was recorded by a sensor glove. The measurement was repeated after an ulnar nerve block was applied in a standardized setting. The change in the temporal coordination of the metacarpophalangeal (MCP), proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints with and without the nerve block was calculated within the same subject. In healthy subjects, the MCP joints started their movement prior to the PIP joints in the middle and ring finger, whereas this occurred in the reverse order at the index and little finger. The DIP joint onset was significantly delayed (P<0.01). With the ulnar nerve block, this coordination shifted towards simultaneous onset of all joints, independent of the grip diameter. The thumb and index finger were affected the least. With an ulnar nerve block, the PIP joints completed their movement prior to the MCP joints when gripping small objects (G1 and G2), whereas the order was reversed with larger objects (G3 and G4). The alterations with ulnar nerve block affected mainly the little finger when gripping small objects. With larger diameter objects, all fingers had a significant delay at the end of the PIP joint movement relative to the MCP and DIP joints, and the PIP and DIP joint sequence was reversed (P<0.01). Based on the significant changes in temporal coordination of finger flexion during different power grips, there are biomechanical effects of loss of function of the intrinsic muscles caused by an ulnar nerve block on the fine motor skills of the hand. This can be important for the diagnosis and rehabilitation of ulnar nerve lesions of the hand. Copyright © 2017 SFCM. Published by Elsevier Masson SAS. All rights reserved.

Geological Disposal of Nuclear Waste: Investigating the Thermo-Hygro-Mechanical-Chemical (THMC) Coupled Processes at the Waste Canister- Bentonite Barrier Interface

NASA Astrophysics Data System (ADS)

Davies, C. W.; Davie, D. C.; Charles, D. A.

2015-12-01

Geological disposal of nuclear waste is being increasingly considered to deal with the growing volume of waste resulting from the nuclear legacy of numerous nations. Within the UK there is 650,000 cubic meters of waste safely stored and managed in near-surface interim facilities but with no conclusive permanent disposal route. A Geological Disposal Facility with incorporated Engineered Barrier Systems are currently being considered as a permanent waste management solution (Fig.1). This research focuses on the EBS bentonite buffer/waste canister interface, and experimentally replicates key environmental phases that would occur after canister emplacement. This progresses understanding of the temporal evolution of the EBS and the associated impact on its engineering, mineralogical and physicochemical state and considers any consequences for the EBS safety functions of containment and isolation. Correlation of engineering properties to the physicochemical state is the focus of this research. Changes to geotechnical properties such as Atterberg limits, swelling pressure and swelling kinetics are measured after laboratory exposure to THMC variables from interface and batch experiments. Factors affecting the barrier, post closure, include corrosion product interaction, precipitation of silica, near-field chemical environment, groundwater salinity and temperature. Results show that increasing groundwater salinity has a direct impact on the buffer, reducing swelling capacity and plasticity index by up to 80%. Similarly, thermal loading reduces swelling capacity by 23% and plasticity index by 5%. Bentonite/steel interaction studies show corrosion precipitates diffusing into compacted bentonite up to 3mm from the interface over a 4 month exposure (increasing with temperature), with reduction in swelling capacity in the affected zone, probably due to the development of poorly crystalline iron oxides. These results indicate that groundwater conditions, temperature and corrosion may affect the engineering performance of the bentonite buffer such that any interfaces between bentonite blocks that may be present immediately following buffer emplacement may persist in the longer term.

Modeling of Coupled Thermo-Hydro-Mechanical-Chemical Processes for Bentonite in a Clay-rock Repository for Heat-generating Nuclear Waste

NASA Astrophysics Data System (ADS)

Xu, H.; Rutqvist, J.; Zheng, L.; Birkholzer, J. T.

2016-12-01

Engineered Barrier Systems (EBS) that include a bentonite-based buffer are designed to isolate the high-level radioactive waste emplaced in tunnels in deep geological formations. The heat emanated from the waste can drive the moisture flow transport and induce strongly coupled Thermal (T), Hydrological (H), Mechanical (M) and Chemical (C) processes within the bentonite buffer and may also impact the evolution of the excavation disturbed zone and the sealing between the buffer and walls of an emplacement tunnel The flow and contaminant transport potential along the disturbed zone can be minimized by backfilling the tunnels with bentonite, if it provides enough swelling stress when hydrated by the host rock. The swelling capability of clay minerals within the bentonite is important for sealing gaps between bentonite block, and between the EBS and the surrounding host rock. However, a high temperature could result in chemical alteration of bentonite-based buffer and backfill materials through illitization, which may compromise the function of these EBS components by reducing their plasticity and capability to swell under wetting. Therefore, an adequate THMC coupling scheme is required to understand and to predict the changes of bentonite for identifying whether EBS bentonite can sustain higher temperatures. More comprehensive links between chemistry and mechanics, taking advantage of the framework provided by a dual-structure model, named Barcelona Expansive Model (BExM), was implemented in TOUGHREACT-FLAC3D and is used to simulate the response of EBS bentonite in in clay formation for a generic case. The current work is to evaluate the chemical changes in EBS bentonite and the effects on the bentonite swelling stress under high temperature. This work sheds light on the interaction between THMC processes, evaluates the potential deterioration of EBS bentonite and supports the decision making in the design of a nuclear waste repository in light of the maximum allowance temperature.

MK-801 increases the baseline level of anxiety in mice introduced to a spatial memory task without prior habituation.

PubMed

Ennaceur, A; Michalikova, S; van Rensburg, R; Chazot, P L

2011-01-01

C57BL/6J mice were introduced to a nine arm radial maze without prior habituation and trained in the acquisition of a working memory task in 16 sessions, one session per day. In this maze mice need to climb onto an upward inclined bridge in order to reach and cross onto an arm. They received in each session an i.p. injection of MK-801 (0.1 mg/kg) 30 min before training or immediately after training. MK-801 pre-treated mice made significantly more entries onto the bridges, fewer entries onto the arms and took significantly longer time to make a first arm visit compared to saline and MK-801 post-treated mice during the first 3 session blocks (4 sessions per block). These results indicate that MK-801 induced anxiety which was extended throughout the first 3 session blocks. MK-801 pre-treated mice made also significantly more errors and required more sessions to reach the criterion compared to saline and MK-801 post-treated mice. Administration of MK-801 after training did not affect the acquisition of the task. The present results indicate that MK-801 pre-treatment impaired the acquisition of a spatial task and this can be accounted for by its effect on the baseline level of anxiety which was elevated. The introduction of mice to the acquisition of the task without prior habituation demonstrates that a drug treatment can affect learning and memory by increasing and/or prolonging anxiety. Such effect may be confounded with learning and memory performance and not detected with pre-habituation training procedures, particularly when the number of sessions is determined a-priori. Copyright © 2011 Elsevier Ltd. All rights reserved.

Mean phase predictor for maximum a posteriori demodulator

NASA Technical Reports Server (NTRS)

Altes, Richard A. (Inventor)

1996-01-01

A system and method for optimal maximum a posteriori (MAP) demodulation using a novel mean phase predictor. The mean phase predictor conducts cumulative averaging over multiple blocks of phase samples to provide accurate prior mean phases, to be input into a MAP phase estimator.

Report: EPA Does Not Effectively Control or Monitor Imports of Hazardous Waste

EPA Pesticide Factsheets

Report #15-P-0172, July 6, 2015. The EPA lacks explicit authority to block imported shipments of hazardous waste that lack prior EPA consent. This could lead to improper handling and disposal, resulting in unknown human and environmental exposure to toxic

Custom-fit total knee arthroplasty: our initial experience in 32 knees.

PubMed

Bali, Kamal; Walker, Peter; Bruce, Warwick

2012-06-01

We share our initial experience of total knee arthroplasty (TKA) using customized cutting block technology in 32 TKAs from May 2010 to March 2011. Ten of these patients had prior TKA done on the other side using conventional or navigation-assisted TKA. Customized cutting blocks were generated for each of the knee using preoperative magnetic resonance imaging of knee and long-leg weight-bearing radiographs. At 6 weeks, long-leg radiographs were obtained to evaluate the coronal alignment. There were no adverse intraoperative events. Twenty-nine of the 32 knees had a mechanical axis restored to within 3°° of neutral. Of 10 patients with prior TKA without custom-fit technology, the mean blood loss and the mean skin-to-skin time was found to be lower in knees that had undergone custom-fit TKA. We conclude that this technology can be safely used in most of the cases of osteoarthritis. Copyright © 2012 Elsevier Inc. All rights reserved.

The role of tortuosity on ion conduction in block copolymer electrolyte thin films

NASA Astrophysics Data System (ADS)

Kambe, Yu; Arges, Christopher G.; Nealey, Paul F.

This talk discusses the role of grain tortuosity on ion conductivity in block copolymer electrolyte (BCE) thin films. In particular, we studied lamellae forming BCEs with both domains oriented perpendicular to the substrate surface and connected directly from one electrode to another - i.e., tortuosity of one. The BCE is composed of ion-conducting, poly(2-vinyl n-methylpyridinium) blocks and non-ionic polystyrene blocks. Prior to creating the BCE, the pristine block copolymer, poly(styrene- b-2-vinyl pyridine), was directly self-assembled (DSA) on topographical or chemical patterns via graphoepitaxy and chemoepitaxy. A chemical vapor infiltration reaction modified the P2VP block into positively charged, fixed quaternary ammonium groups paired with mobile counteranions. The graphoepitaxy process utilized topographical interdigitated gold nanoelectrodes (100s of nanometers spacing between electrodes) created via e-beam lithography. Alternatively, chemical patterns had gold electrodes incorporated into them with 10s to 100s of microns spacing using conventional optical lithography. The interdigitated gold electrodes enabled in-plane ion conductivity measurements of the DSA BCEs to study the role of grain tortuosity on ion conductivity. U.S. Department of Energy Office of Science: Contract No. DE-AC02-06CH11357.

Fluorescent Cell Barcoding for Multiplex Flow Cytometry

PubMed Central

Krutzik, Peter O.; Clutter, Matthew R.; Trejo, Angelica; Nolan, Garry P.

2011-01-01

Fluorescent Cell Barcoding (FCB) enables high throughput, i.e. high content flow cytometry by multiplexing samples prior to staining and acquisition on the cytometer. Individual cell samples are barcoded, or labeled, with unique signatures of fluorescent dyes so that they can be mixed together, stained, and analyzed as a single sample. By mixing samples prior to staining, antibody consumption is typically reduced 10 to 100-fold. In addition, data robustness is increased through the combination of control and treated samples, which minimizes pipetting error, staining variation, and the need for normalization. Finally, speed of acquisition is enhanced, enabling large profiling experiments to be run with standard cytometer hardware. In this unit, we outline the steps necessary to apply the FCB method to cell lines as well as primary peripheral blood samples. Important technical considerations such as choice of barcoding dyes, concentrations, labeling buffers, compensation, and software analysis are discussed. PMID:21207359

Bleach Gel: A Simple Agarose Gel for Analyzing RNA Quality

PubMed Central

Aranda, Patrick S.; LaJoie, Dollie M.; Jorcyk, Cheryl L.

2013-01-01

RNA-based applications requiring high quality, non-degraded RNA are a foundational element of many research studies. As such, it is paramount that the integrity of experimental RNA is validated prior to cDNA synthesis or other downstream applications. In the absence of expensive equipment such as microfluidic electrophoretic devices, and as an alternative to the costly and time-consuming standard formaldehyde gel, RNA quality can be quickly analyzed by adding small amounts of commercial bleach to TAE buffer-based agarose gels prior to electrophoresis. In the presence of low concentrations of bleach, the secondary structure of RNA is denatured and potential contaminating RNases are destroyed. Because of this, the ‘bleach gel’ is a functional approach that addresses the need for an inexpensive and safe way to evaluate RNA integrity and will improve the ability of researchers to rapidly analyze RNA quality. PMID:22222980

Ca2+ current vs. Ca2+ channel cooperativity of exocytosis

PubMed Central

Matveev, Victor; Bertram, Richard; Sherman, Arthur

2009-01-01

Recently there has been significant interest and progress in the study of spatio-temporal dynamics of Ca2+ that triggers exocytosis at a fast chemical synapse, which requires understanding the contribution of individual calcium channels to the release of a single vesicle. Experimental protocols provide insight into this question by probing the sensitivity of exocytosis to Ca2+ influx. While varying extracellular or intracellular Ca2+ concentration assesses the intrinsic biochemical Ca2+ cooperativity of neurotransmitter release, varying the number of open Ca2+ channels using pharmacological channel block or the tail current titration probes the cooperativity between individual Ca2+ channels in triggering exocytosis. Despite the wide use of these Ca2+ sensitivity measurements, their interpretation often relies on heuristic arguments. Here we provide a detailed analysis of the Ca2+ sensitivity measures probed by these experimental protocols, present simple expressions for special cases, and demonstrate the distinction between the Ca2+ current cooperativity, defined by the relationship between exocytosis rate and the whole-terminal Ca2+ current magnitude, and the underlying Ca2+ channel cooperativity, defined as the average number of channels involved in the release of a single vesicle. We find simple algebraic expressions that show that the two are different but linearly related. Further, we use 3D computational modeling of buffered Ca2+ diffusion to analyze these distinct Ca2+ cooperativity measures, and demonstrate the role of endogenous Ca2+ buffers on such measures. We show that buffers can either increase or decrease the Ca2+ current cooperativity of exocytosis, depending on their concentration and the single-channel Ca2+ current. PMID:19793978

Effective and ineffective coping strategies in a low-autonomy work environment.

PubMed

Britt, Thomas W; Crane, Monique; Hodson, Stephanie E; Adler, Amy B

2016-04-01

The authors examined the effectiveness of different coping strategies in buffering the negative effects of uncontrollable stressors and predicting mental health symptoms in a low-autonomy work environment using a longitudinal design. Soldiers in training indicated the extent to which they engaged in various coping strategies to deal with stressors related to the training environment at 4 different points in time. Factor analyses of soldiers in 2 different countries (i.e., United States and Australia) yielded 5 coping dimensions: active coping, acceptance of demands, seeking social support, humor, and denial/self-criticism. Among U.S. soldiers in basic training, acceptance of demands and denial/self-criticism interacted with the magnitude of basic-training stressors to predict mental health symptoms (depression and anxiety) at 3 different points during training while controlling for symptoms at the immediate prior time period. Acceptance buffered soldiers from the negative effects of the stressors, whereas denial/self-criticism exacerbated the effects of the stressors. The results of LGC models also indicated that the slopes of acceptance and active coping were negatively related to the slope of mental health symptoms across training, whereas the slope for denial/self-criticism was positively related to the slope of symptoms. Active coping was less predictive of functioning in the face of stressors and in the prediction of symptoms over time. The results demonstrated that in a low-autonomy occupational setting, acceptance coping was more effective in facilitating good mental health outcomes compared with other coping strategies considered important in prior research (e.g., active coping). (c) 2016 APA, all rights reserved).

Simulation Study of Single-Event Burnout in Power Trench ACCUFETs

NASA Astrophysics Data System (ADS)

Yu, Cheng-Hao; Wang, Ying; Fei, Xin-Xing; Cao, Fei

2016-10-01

This paper presents 2-D numerical simulation results of single-event burnout (SEB) in power trench accumulation mode field effect transistor (ACCUFET) for the first time. In this device, a p+ base region is used to deplete the n- base region to achieve a low leakage current density, and the blocking voltage is supported by the n- drift region. We find that the depth of the p+ base region determines both the leakage current density and SEB performance, as a result, there is a tradeoff relationship between the two characteristics. The 60 V hardened power ACCUFET shown in this paper could demonstrate much better SEB performance without sacrificing the current handling capability compared with the standard UMOSFET. The hardened structure mentioned in this paper indicates that an n buffer layer is added between the epitaxial layer and substrate layer based on a basic power device. As a result, the safe operating area (SOA) of the 60 V, 80 V and 100 V hardened ACCUFET discussed in this paper could reach the value of breakdown voltage when the buffer layer is over a certain value, that can realize safety operation throughout entire LET range.

Mesoporous titanosilicates with high loading of titanium synthesized in mild acidic buffer solution.

PubMed

Tang, Jianting; Liu, Jian; Yang, Jie; Feng, Zhaochi; Fan, Fengtao; Yang, Qihua

2009-07-15

Mesoporous titanosilicates with high titanium content were synthesized under mild acidic conditions (pH=4.4, HAc-NaAc buffer solution) by co-condensation of acetylacetone-modified titanium isopropoxide (Ti(OBu(n))(3) (acac)) and mixture of sodium silicate with tetramethoxysilane (TMOS) or tetraethoxysilane (TEOS) or tetrakis(2-hydroxyethyl)orthosilicate (EGMS), using block copolymer Pluronic P123 as template. The combined results of XRD, N(2) sorption and TEM show that the highly regular structure of the mesoporous titanosilicates can still be obtained when Ti/Si molar ratio in the final product is as high as 0.059. The results of UV-vis diffuse reflectance spectra and UV resonance Raman spectra show that the framework titanium species are predominant in the mesoporous titanosilicates when Ti/Si molar ratio in the final product is less than 0.042. The mixture of sodium silicate and EGMS was proved to be the best silicon source for the synthesis of titanosilicates with ordered mesostructure and high titanium content. The efficiency of this synthetic method may be attributed to the mild acidic medium as well as the modified hydrolysis-condensation rate and hydrophility of the precursors.

Effects of workplace intervention on affective well-being in employees' children.

PubMed

Lawson, Katie M; Davis, Kelly D; McHale, Susan M; Almeida, David M; Kelly, Erin L; King, Rosalind B

2016-05-01

Using a group-randomized field experimental design, this study tested whether a workplace intervention-designed to reduce work-family conflict-buffered against potential age-related decreases in the affective well-being of employees' children. Daily diary data were collected from 9- to 17-year-old children of parents working in an information technology division of a U.S. Fortune 500 company prior to and 12 months after the implementation of the Support-Transform-Achieve-Results (STAR) workplace intervention. Youth (62 with parents in the STAR group, 41 in the usual-practice group) participated in 8 consecutive nightly phone calls, during which they reported on their daily stressors and affect. Well-being was indexed by positive and negative affect and affective reactivity to daily stressful events. The randomized workplace intervention increased youth positive affect and buffered youth from age-related increases in negative affect and affective reactivity to daily stressors. Future research should test specific conditions of parents' work that may penetrate family life and affect youth well-being. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Salivary buffer effect in relation to late pregnancy and postpartum.

PubMed

Laine, M; Pienihäkkinen, K

2000-02-01

We studied the salivary pH, buffer effect (BE), and flow rates of unstimulated and paraffin-stimulated saliva of 8 women in their late pregnancy and postpartum. Salivary samples were collected about 1 month prior to and about 2 months after delivery. In non-pregnant control women, two paraffin-stimulated salivary samples were collected 1 month apart. The salivary BE increased significantly from late pregnancy to postpartum without exception. The increase was 2.04 +/- 1.17 pH units (P < 0.001) on average. The BE increased from 4.79 +/- 1.64 (final pH) to 6.82 +/- 1.01 (final pH). This change was not due to variation in salivary flow rates, since both unstimulated and paraffin-stimulated flow rates remained unchanged. In control women the difference between the 2 BE measurements was only 0.13 +/- 0.47 pH units on average. We concluded that women with high postpartum BE values may have moderate or even low BE values in late pregnancy. In control women, individual variation was found to be low in all variables studied.

Development and validation of a capillary electrophoresis method for the determination of codeine, diphenhydramine, ephedrine and noscapine in pharmaceuticals.

PubMed

Gomez, María R; Sombra, Lorena; Olsina, Roberto A; Martínez, Luis D; Silva, María F

2005-01-01

The present work describes a simple, accurate and rapid method for the separation and simultaneous determination of codeine, diphenhydramine, ephedrine and noscapine present in cough-cold syrup formulations by capillary zone electrophoresis. Factors affecting the separation were the buffer pH and concentration, applied voltage, and presence of additives. Separations were carried out in less than 10 min with a 20 mM sodium tetraborate buffer, pH 8.50. The carrier electrolyte gave baseline separation with good resolution, great reproducibility and accuracy. Calibration plots were linear over at least three orders of magnitude of analyte concentrations, the lower limits of detection being within the range 0.42-1.33 microg ml(-1). Detection was performed by UV absorbance at wavelengths of 205 and 250 nm. Quantification of the components in actual syrup formulations was calculated against the responses of freshly prepared external standard solutions. The method was validated and met all analysis requirements of quality assurance and quality control. The procedure was fast and reliable and commercial pharmaceuticals could be analyzed without prior sample clean-up procedure.

Plasma-assisted Molecular Beam Epitaxy of N-polar InAlN-barrier High-electron-mobility Transistors.

PubMed

Hardy, Matthew T; Storm, David F; Katzer, D Scott; Downey, Brian P; Nepal, Neeraj; Meyer, David J

2016-11-24

Plasma-assisted molecular beam epitaxy is well suited for the epitaxial growth of III-nitride thin films and heterostructures with smooth, abrupt interfaces required for high-quality high-electron-mobility transistors (HEMTs). A procedure is presented for the growth of N-polar InAlN HEMTs, including wafer preparation and growth of buffer layers, the InAlN barrier layer, AlN and GaN interlayers and the GaN channel. Critical issues at each step of the process are identified, such as avoiding Ga accumulation in the GaN buffer, the role of temperature on InAlN compositional homogeneity, and the use of Ga flux during the AlN interlayer and the interrupt prior to GaN channel growth. Compositionally homogeneous N-polar InAlN thin films are demonstrated with surface root-mean-squared roughness as low as 0.19 nm and InAlN-based HEMT structures are reported having mobility as high as 1,750 cm 2 /V∙sec for devices with a sheet charge density of 1.7 x 10 13 cm -2 .

Thermal and unroofing history of a thick, tilted Basin-and-Range crustal section in the Tortilla Mountains, Arizona

USGS Publications Warehouse

Howard, K.A.; Foster, D.A.

1996-01-01

We estimate here a geothermal gradient of only 17 ?? 5??C km-1 for the tilted Grayback fault block in southeastern Arizona when extension began ???25 Ma. This gradient is lower than preextension gradients estimated elsewhere in the Basin and Range, is only about 50% of typical gradients in the Basin and Range today, and needs to be accounted for in models of continental extension. The Grayback block exposes a 12-km-thick crustal section of Proterozoic and Cretaceous granitoids, which was tilted 90?? during extension between 25 and 15 Ma. Zircon fission-track ages decrease structurally downward (westward) across the block and were all within a zone of partial track annealing prior to tilting and quenching. The zircon age gradient suggests that the 220??-240??C isotherm migrated downward 5-6 km during Paleogene erosion and regional cooling. Apatite fission-track ages decrease westward from ???83 Ma in the structurally highest crystalline rocks to ???24 Ma at ???6-km paleodepth and then to ???15 Ma another 6 km farther west. Track-length analysis confirms that apatites above the break in slope in age at ???5.7-km paleodepth resided in a zone of partial annealing prior to tilting, and deeper apatites record rapid cooling upon tilting and unroofing beginning ???25 Ma. At that time the 110 ?? 10??C isotherm determined by the depth at which tracks in apatite were fully erased was at a basement paleodepth of ???5.7 km, and the 220 ?? 30??C isotherm as estimated from zircon data resided at a pretilting basement depth of ???12.15 km. From consistent values of paleogeothermal gradient for two depth intervals we estimate the pretilt gradient was 17 ?? 5??C km-1. From 25 to 15 Ma the rotating Grayback block cooled rapidly as higher, westward moving blocks unroofed it tectonically at a rate of ???1 km m.y.-1.

30 CFR 75.222 - Roof control plan-approval criteria.

Code of Federal Regulations, 2014 CFR

2014-07-01

... systems. (1) Systematic supplemental support should be installed throughout— (i) The tailgate entry of the first longwall panel prior to any mining; and (ii) In the proposed tailgate entry of each subsequent... should address— (i) Notification of miners that the travelway is blocked; (ii) Re-instruction of miners...

30 CFR 75.222 - Roof control plan-approval criteria.

Code of Federal Regulations, 2012 CFR

2012-07-01

... systems. (1) Systematic supplemental support should be installed throughout— (i) The tailgate entry of the first longwall panel prior to any mining; and (ii) In the proposed tailgate entry of each subsequent... should address— (i) Notification of miners that the travelway is blocked; (ii) Re-instruction of miners...

30 CFR 75.222 - Roof control plan-approval criteria.

Code of Federal Regulations, 2013 CFR

2013-07-01

... systems. (1) Systematic supplemental support should be installed throughout— (i) The tailgate entry of the first longwall panel prior to any mining; and (ii) In the proposed tailgate entry of each subsequent... should address— (i) Notification of miners that the travelway is blocked; (ii) Re-instruction of miners...

Blocking Effects in the Learning of Chinese Classifiers

ERIC Educational Resources Information Center

Paul, Jing Z.; Grüter, Theres

2016-01-01

This study investigated order-of-learning effects on the acquisition of classifier-noun associations in Chinese in two experiments modeled after Arnon and Ramscar's (2012) study of artificial language learning. In Experiment 1, learners with no prior exposure to Chinese showed better learning of classifier-noun associations when exposed to larger…

Ethamsylate in vaginal surgery under lumbar epidural anaesthesia.

PubMed Central

Smith, G. B.; Eltringham, R. J.; Nightingale, J. J.

1983-01-01

Sixty patients scheduled for vaginal surgery under lumbar epidural block were randomly allocated into two groups, one of which received ethamsylate intravenously prior to induction of anaesthesia. Ethamsylate did not reduce the blood loss at operation in these patients. The possible factors underlying this observation are discussed. PMID:6338800

21 CFR 522.1372 - Mepivacaine.

Code of Federal Regulations, 2012 CFR

2012-04-01

..., 10 to 15 mL; for infiltration, as required; for anesthesia of the laryngeal mucosa prior to ventriculectomy, by topical spray, 25 to 40 mL, by infiltration, 20 to 50 mL. (2) Indications for use. For use as a local anesthetic for infiltration, nerve block, intra-articular and epidural anesthesia, and...

21 CFR 522.1372 - Mepivacaine.

Code of Federal Regulations, 2013 CFR

2013-04-01

..., 10 to 15 mL; for infiltration, as required; for anesthesia of the laryngeal mucosa prior to ventriculectomy, by topical spray, 25 to 40 mL, by infiltration, 20 to 50 mL. (2) Indications for use. For use as a local anesthetic for infiltration, nerve block, intra-articular and epidural anesthesia, and...

21 CFR 522.1372 - Mepivacaine.

Code of Federal Regulations, 2014 CFR

2014-04-01

..., 10 to 15 mL; for infiltration, as required; for anesthesia of the laryngeal mucosa prior to ventriculectomy, by topical spray, 25 to 40 mL, by infiltration, 20 to 50 mL. (2) Indications for use. For use as a local anesthetic for infiltration, nerve block, intra-articular and epidural anesthesia, and...

21 CFR 522.1372 - Mepivacaine.

Code of Federal Regulations, 2010 CFR

2010-04-01

..., 10 to 15 mL; for infiltration, as required; for anesthesia of the laryngeal mucosa prior to ventriculectomy, by topical spray, 25 to 40 mL, by infiltration, 20 to 50 mL. (2) Indications for use. For use as a local anesthetic for infiltration, nerve block, intra-articular and epidural anesthesia, and...

21 CFR 522.1372 - Mepivacaine.

Code of Federal Regulations, 2011 CFR

2011-04-01

..., 10 to 15 mL; for infiltration, as required; for anesthesia of the laryngeal mucosa prior to ventriculectomy, by topical spray, 25 to 40 mL, by infiltration, 20 to 50 mL. (2) Indications for use. For use as a local anesthetic for infiltration, nerve block, intra-articular and epidural anesthesia, and...

Critical Building Blocks: Mandatory Prerequisite Registration Systems and Student Success

ERIC Educational Resources Information Center

Soria, Krista M.; Mumpower, Lori

2012-01-01

Many colleges and universities require prerequisites prior to enrollment in introductory composition courses; however, enforcement of prerequisites is not consistent across institutions. In this study, we examine the impact of an automated, mandatory prerequisite enforcement system on students and advisors at a public comprehensive university.…

45 CFR 96.92 - Termination of funding.

Code of Federal Regulations, 2014 CFR

2014-10-01

... the Community Services Block Grant Act that it will terminate present or future funding of any... the record prior to terminating funding. If a review by the Secretary of the State's final decision to... of notification by the State of its final decision to terminate funding. The Department will confirm...

45 CFR 96.92 - Termination of funding.

Code of Federal Regulations, 2012 CFR

2012-10-01

... the Community Services Block Grant Act that it will terminate present or future funding of any... the record prior to terminating funding. If a review by the Secretary of the State's final decision to... of notification by the State of its final decision to terminate funding. The Department will confirm...

45 CFR 96.92 - Termination of funding.

Code of Federal Regulations, 2011 CFR

2011-10-01

... the Community Services Block Grant Act that it will terminate present or future funding of any... the record prior to terminating funding. If a review by the Secretary of the State's final decision to... of notification by the State of its final decision to terminate funding. The Department will confirm...

45 CFR 96.92 - Termination of funding.

Code of Federal Regulations, 2013 CFR

2013-10-01

... the Community Services Block Grant Act that it will terminate present or future funding of any... the record prior to terminating funding. If a review by the Secretary of the State's final decision to... of notification by the State of its final decision to terminate funding. The Department will confirm...

28 CFR 51.28 - Supplemental contents.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Information Processing Standards (FIPS-55) code. (v) Census tracts shall be left justified, and census blocks shall be left justified and blank filled if less than four characters. (vi) Unused plan fields shall be... affected, containing the following information: (1) The prior and new boundaries of the voting unit or...

Efficacy of copper and silver ions with iodine in the inactivation of Pseudomonas cepacia

NASA Technical Reports Server (NTRS)

Pyle, B. H.; Broadaway, S. C.; McFeters, G. A.

1992-01-01

Alternatives to chlorination of water have been sought for reasons which include trihalomethane formation, possible bacterial regrowth, the high concentrations of chlorine required in certain circumstances, and the taste, odour and bodily irritation in chlorine-treated water. Electrolytically generated Cu and Ag ions at low levels, in addition to very low chlorine concentrations, have been suggested as an alternative to routine chlorination. We have examined the combination of Cu and Ag ions with low levels of iodine. Pseudomonas cepacia was grown either in rich medium or under nutrient restriction prior to disinfection. Survival of the organism and its ability to regrow after treatment as well as the effects of varying buffers, metal ion and iodine concentrations were determined. Low concentrations of metal ions (100 ppb Cu and 11 ppb Ag) and iodine (200 ppb) were more effective than either metal ions or iodine alone against Ps. cepacia grown on rich agar or in low nutrient buffer. After iodination, buffer-grown suspensions recovered to their original cell concentrations within 7 d. When Cu and Ag ions were used with or without iodine, regrowth was prevented. The results show that low concentrations of Cu and Ag in combination with iodine permit effective disinfection of bacteria after cultivation on either rich media or under nutrient restriction. These results, along with published data, suggest that the combination of these metals with halogenation may have applications in the disinfection of both recreational and potable water.

More is less: Learning but not relaxing buffers deviance under job stressors.

PubMed

Zhang, Chen; Mayer, David M; Hwang, Eunbit

2018-02-01

Workplace deviance harms the well-being of an organization and its members. Unfortunately, theory and prior research suggest that deviance is associated with job stressors, which are endemic to work organizations and often cannot be easily eliminated. To address this conundrum, we explore actions individuals can take at work that serve as buffering conditions for the positive relationship between job stressors and deviant behavior. Drawing upon conservation of resources theory, we examine a resource-building activity (i.e., learning something new at work) and a demand-shielding activity (i.e., taking time for relaxation at work) as potential boundary conditions. In 2 studies with employee samples using complementary designs, we find support for the buffering role of learning but not for relaxation. When employees learn new things at work, the relationship between hindrance stressors and deviance is weaker; as is the indirect relationship mediated by negative emotions. Taking time for relaxation at work did not show a moderating role in either study. Therefore, although relaxation is a response that individuals might be inclined to turn to for counteracting work stress, our findings suggest that, when it comes to addressing negative emotions and deviance in stressful work environments, building positive resources by learning something new at work could be more useful. In that way, doing more (i.e., learning, and not relaxing) is associated with less (deviance) in the face of job stressors. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Reducing Backups by Utilizing DMF

NASA Technical Reports Server (NTRS)

Cardo, Nicholas P.; Woodrow, Thomas (Technical Monitor)

1994-01-01

Although a filesystem may be migratable, for a period of time the data blocks are on disk only. When performing system dumps, these data blocks are backed up to tape. If the data blocks are offline or dual resident, then only the inode is backed up. If all online files are made dual resident prior to performing system dumps, the dump time and the amount of resources required can be significantly reduced. The High Speed Processors group at the Numerical Aerodynamics Simulation (NAS) Facility at NASA Ames Research Center developed a tool to make all online files dual resident. The result is that a file whose data blocks are on DMF tape and still assigned to the original inode. Our 150GB filesystem used to take 8 to 12 hours to backup and used 50 to 60 tapes. Now the backup is typically under 10 tapes and completes in under 2 hours. This paper discusses this new tool and advantages gained by using it.

Statistical Analysis of the Links between Blocking and Nor'easters

NASA Astrophysics Data System (ADS)

Booth, J. F.; Pfahl, S.

2015-12-01

Nor'easters can be loosely defined as extratropical cyclones that develop as they progress northward along the eastern coast of North America. The path makes it possible for these storms to generate storm surge along the coastline and/or heavy precipitation or snow inland. In the present analysis, the path of the storms is investigated relative to the behavior of upstream blocking events over the North Atlantic Ocean. For this analysis, two separate Lagrangian tracking methods are used to identify the extratropical cyclone paths and the blocking events. Using the cyclone paths, Nor'easters are identified and blocking statistics are calculated for the days prior to, during and following the occurrence of the Nor'easters. The path, strength and intensification rates of the cyclones are compared with the strength and location of the blocks. In the event that a Nor'easter occurs, the likelihood of the presence of block at the southeast tip of Greenland is statistically significantly increased, i.e., the presence of a block concurrent with a Nor'easter happens more often than by random coincidence. However no significant link between the strength of the storms and the strength of the block is identified. These results suggest that the presence of the block mainly affects the path of the Nor'easters. On the other hand, in the event of blocking at the southeast tip of Greenland, the likelihood of a Nor'easter, as opposed to a different type of storm is no greater than what one might expect from randomly sampling cyclone tracks. The results confirm a long held understanding in forecast meteorology that upstream blocking is a necessary but not sufficient condition for generating a Nor'easter.

Wrong-site nerve blocks: A systematic literature review to guide principles for prevention.

PubMed

Deutsch, Ellen S; Yonash, Robert A; Martin, Donald E; Atkins, Joshua H; Arnold, Theresa V; Hunt, Christina M

2018-05-01

Wrong-site nerve blocks (WSBs) are a significant, though rare, source of perioperative morbidity. WSBs constitute the most common type of perioperative wrong-site procedure reported to the Pennsylvania Patient Safety Authority. This systematic literature review aggregates information about the incidence, patient consequences, and conditions that contribute to WSBs, as well as evidence-based methods to prevent them. A systematic search of English-language publications was performed, using the PRISMA process. Seventy English-language publications were identified. Analysis of four publications reporting on at least 10,000 blocks provides a rate of 0.52 to 5.07 WSB per 10,000 blocks, unilateral blocks, or "at risk" procedures. The most commonly mentioned potential consequence was local anesthetic toxicity. The most commonly mentioned contributory factors were time pressure, personnel factors, and lack of site-mark visibility (including no site mark placed). Components of the block process that were addressed include preoperative nerve-block verification, nerve-block site marking, time-outs, and the healthcare facility's structure and culture of safety. A lack of uniform reporting criteria and divergence in the data and theories presented may reflect the variety of circumstances affecting when and how nerve blocks are performed, as well as the infrequency of a WSB. However, multiple authors suggest three procedural steps that may help to prevent WSBs: (1) verify the nerve-block procedure using multiple sources of information, including the patient; (2) identify the nerve-block site with a visible mark; and (3) perform time-outs immediately prior to injection or instillation of the anesthetic. Hospitals, ambulatory surgical centers, and anesthesiology practices should consider creating site-verification processes with clinician input and support to develop sustainable WSB-prevention practices. Copyright © 2017 Elsevier Inc. All rights reserved.

Hemodynamic stability ensured by a low dose, low volume, unilateral hypobaric spinal block: modification of a technique.

PubMed

Elzinga, L; Marcus, M; Peek, D; Borg, P; Jansen, J; Koster, J; Enk, D

2009-01-01

We report the case of an 89-year-old female with a history of arterial hypertension, intermittent rapid atrial fibrillation and severe aortic valve stenosis, suffering from femoral neck fracture. Hyperbaric unilateral spinal anesthesia is a known technique to obtain stable hemodynamics combined with the possibility of continuous neurologic evaluation and preservation of cognitive functions. Because a hyperbaric unilateral technique can be very painful in case of traumatic hip fracture, a low dose, low volume, unilateral hypobaric spinal block may be an adequate alternative. In the present case report, a unilateral hypobaric spinal anesthesia was performed using 5 mg of bupivacaine in a 1.5 mL volume and a slow and steady, "air-buffered", directed injection technique, to allow an urgent hip arthroplasty. During surgery the patient was kept in the lateral recumbent position. Hemodynamics remained stable throughout the entire procedure without any need for vasoconstrictors. The impact of aortic valve stenosis combined with atrial fibrillation on anesthetic management and our considerations to opt for a unilateral hypobaric spinal anesthesia are discussed.

Enzyme-directed assembly of nanoparticles in tumors monitored by in vivo whole animal imaging and ex vivo super-resolution fluorescence imaging.

PubMed

Chien, Miao-Ping; Carlini, Andrea S; Hu, Dehong; Barback, Christopher V; Rush, Anthony M; Hall, David J; Orr, Galya; Gianneschi, Nathan C

2013-12-18

Matrix metalloproteinase enzymes, overexpressed in HT-1080 human fibrocarcinoma tumors, were used to guide the accumulation and retention of an enzyme-responsive nanoparticle in a xenograft mouse model. The nanoparticles were prepared as micelles from amphiphilic block copolymers bearing a simple hydrophobic block and a hydrophilic peptide brush. The polymers were end-labeled with Alexa Fluor 647 dyes leading to the formation of labeled micelles upon dialysis of the polymers from DMSO/DMF to aqueous buffer. This dye-labeling strategy allowed the presence of the retained material to be visualized via whole animal imaging in vivo and in ex vivo organ analysis following intratumoral injection into HT-1080 xenograft tumors. We propose that the material is retained by virtue of an enzyme-induced accumulation process whereby particles change morphology from 20 nm spherical micelles to micrometer-scale aggregates, kinetically trapping them within the tumor. This hypothesis is tested here via an unprecedented super-resolution fluorescence analysis of ex vivo tissue slices confirming a particle size increase occurs concomitantly with extended retention of responsive particles compared to unresponsive controls.

Evaluating Options for Measurement of Neighborhood Socioeconomic Context: Evidence from a Myocardial Infarction Case-Control Study

PubMed Central

Lovasi, Gina S.; Moudon, Anne Vernez; Smith, Nicholas L.; Lumley, Thomas; Larson, Eric B.; Sohn, Dong W; Siscovick, David S; Psaty, Bruce M

2008-01-01

We hypothesized that neighborhood socioeconomic context would be most stronly associated with risk of myocardial infarction (MI) for smaller “neighborhood” definitions. We used data on 487 non-fatal, incident MI cases and 1,873 controls from a case-control study in Washington State. Census data on income, home ownership, and education were used to estimate socioeconomic context across four neighborhood definitions: one-kilometer buffer, block group, census tract, and ZIP code. No neighborhood definition led to consistently stronger associations with MI. Although we confirmed the association between neighborhood socioeconomic measures and risk of MI, we did not find these associations sensitive to neighborhood definition. PMID:17950024

Method for eliminating gas blocking in electrokinetic pumping systems

DOEpatents

Arnold, Don W.; Paul, Phillip H.; Schoeniger, Joseph S.

2001-09-11

A method for eliminating gas bubble blockage of current flow during operation of an electrokinetic pump. By making use of the ability to modify the surface charge on the porous dielectric medium used in electrokinetic pumps, it becomes possible to place electrodes away from the pressurized region of the electrokinetic pump. While gas is still generated at the electrodes they are situated such that the generated gas can escape into a larger buffer reservoir and not into the high pressure region of the pump where the gas bubbles can interrupt current flow. Various combinations of porous dielectric materials and ionic conductors can be used to create pumps that have desirable electrical, material handling, and flow attributes.

Inhibition of rat brain monoamine oxidase by repeated administration of pirlindol

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

Verevkina, I.V.; Asnina, V.V.; Gorkin, V.Z.

1985-10-01

Since pirlindol, like other antidepressants, is used for a long time and since its therapeutic effect usually appears 5-7 days or more after the beginning of treatment, the authors investigate its action on activity of MAO of types A and B in rat brain when administered repeatedly. MAO activity was determined in 50% homogenates of rat brain, made up in 10 mM phosphate buffer, pH 7.4, containing 2% detergent Triton X-100. It is shown that an important role in the antidepressant effect of pirlindol is played by its property of selectively blocking deamination of neurotrans mitters such as serotonin andmore » noradrenalin in the human brain.« less

Inferior vena cava segmentation with parameter propagation and graph cut.

PubMed

Yan, Zixu; Chen, Feng; Wu, Fa; Kong, Dexing

2017-09-01

The inferior vena cava (IVC) is one of the vital veins inside the human body. Accurate segmentation of the IVC from contrast-enhanced CT images is of great importance. This extraction not only helps the physician understand its quantitative features such as blood flow and volume, but also it is helpful during the hepatic preoperative planning. However, manual delineation of the IVC is time-consuming and poorly reproducible. In this paper, we propose a novel method to segment the IVC with minimal user interaction. The proposed method performs the segmentation block by block between user-specified beginning and end masks. At each stage, the proposed method builds the segmentation model based on information from image regional appearances, image boundaries, and a prior shape. The intensity range and the prior shape for this segmentation model are estimated based on the segmentation result from the last block, or from user- specified beginning mask if at first stage. Then, the proposed method minimizes the energy function and generates the segmentation result for current block using graph cut. Finally, a backward tracking step from the end of the IVC is performed if necessary. We have tested our method on 20 clinical datasets and compared our method to three other vessel extraction approaches. The evaluation was performed using three quantitative metrics: the Dice coefficient (Dice), the mean symmetric distance (MSD), and the Hausdorff distance (MaxD). The proposed method has achieved a Dice of [Formula: see text], an MSD of [Formula: see text] mm, and a MaxD of [Formula: see text] mm, respectively, in our experiments. The proposed approach can achieve a sound performance with a relatively low computational cost and a minimal user interaction. The proposed algorithm has high potential to be applied for the clinical applications in the future.

The unsteady end to a powerful Plinian eruption: insights from a Vulcanian block apron from the 1912 eruption of Novarupta, Alaska

NASA Astrophysics Data System (ADS)

Isgett, S. J.; Houghton, B. F.; Burgisser, A.; Arbaret, L.

2016-12-01

Current models propose a static conduit architecture prior to Vulcanian eruptions where a dense, outgassed dome/plug overlies an orderly, texturally horizontally layered conduit. Blocks from a Vulcanian phase (Episode IV) during the 1912 eruption of Novarupta provide special insight to the state of the magma within a complex shallow conduit prior to fragmentation. Extreme conduit heterogeneity is seen in a diverse range of dacitic block types, including pumiceous, dense, flow-banded, and variably welded breccia clasts, all with a range of surface-breadcrusting. Diverse 2D and 3D textures suggest a variety of degassing states, with ranges of vesicle textures (e.g. bubble number, shape, and size) in each of the block types. The nonbreadcrusted pumice exhibit textures similar to preceding Plinian phases, reflecting bubble nucleation, growth, and coalescence followed by fragmentation. Breadcrusted rind and dense dacite textures are the result of bubble collapse with the dense dacites progressing furthest along the outgassing pathway. Residual water contents within the quenched glass are all less than 0.5 wt% and indicate that the melt came from the upper 100 m of the conduit. There is no correlation between water content and vesicularity. Overall, the evidence indicates 1) the mingling of variably degassed and outgassed melts in varying states of chemical disequilibrium over a narrow depth range close to the surface and 2) fragmentation was probably driven by the melt forming the non-breadcrusted pumices which we consider was probably newly arrived in the shallow conduit at the time of fragmentation. We therefore propose a revised, dynamic model applicable to Vulcanian explosions in the context of downscaling Plinian eruptions that involves vigorous mingling of melts that are all actively degassing and outgassing to varying degrees within the shallow conduit.

Mutation of the dengue virus type 2 envelope protein heparan sulfate binding sites or the domain III lateral ridge blocks replication in Vero cells prior to membrane fusion

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

Roehrig, John T., E-mail: jtr1@cdc.gov; Butrapet, Siritorn; Liss, Nathan M.

Using an infectious cDNA clone we engineered seven mutations in the putative heparan sulfate- and receptor-binding motifs of the envelope protein of dengue virus serotype 2, strain 16681. Four mutant viruses, KK122/123EE, E202K, G304K, and KKK305/307/310EEE, were recovered following transfection of C6/36 cells. A fifth mutant, KK291/295EE, was recovered from C6/36 cells with a compensatory E295V mutation. All mutants grew in and mediated fusion of virus-infected C6/36 cells, but three of the mutants, KK122/123EE, E202K, G304K, did not grow in Vero cells without further modification. Two Vero cell lethal mutants, KK291/295EV and KKK307/307/310EEE, failed to replicate in DC-SIGN-transformed Raji cellsmore » and did not react with monoclonal antibodies known to block DENV attachment to Vero cells. Additionally, both mutants were unable to initiate negative-strand vRNA synthesis in Vero cells by 72 h post-infection, suggesting that the replication block occurred prior to virus-mediated membrane fusion. - Highlights: • Heparan sulfate- and receptor-binding motifs of DENV2 envelope protein were mutated. • Four mutant viruses were isolated—all could fuse C6/36 cells. • Two of these mutants were lethal in Vero cells without further modification. • Lethal mutations were KK291/295EV and KKK305/307/310EEE. • Cell attachment was implicated as the replication block for both mutants.« less

Trazodone and Omeprazole Interaction causing Frequent Second-Degree Mobitz Type 1 Atrioventricular (AV) Block (Wenckebach Phenomenon) and Syncope: A Case Report and Literature Review

PubMed Central

Akinseye, Oluwaseun A.; Alfishawy, Mostafa; Radparvar, Farshid; Bakshi, Sanjiv

2015-01-01

Patient: Male, 54 Final Diagnosis: Trazodone and omeprazole interaction causing second-degree Mobitz type 1 AV block and syncope Symptoms: Syncope Medication: — Clinical Procedure: Trazodone and omeprazole withheld Specialty: Cardiology Objective: Unexpected drug reaction Background: This case report highlights serious cardiovascular adverse effects with a conventional dose of trazodone as a result of its potential interaction with omeprazole. Case Report: A 54-year-old man who was a former smoker, with dyslipidemia, coronary artery disease, and anxiety disorder developed lightheadedness and syncope the morning of admission. He was taking trazodone 50 mg daily, omeprazole 20 mg daily, and simvastatin 20 mg at bedtime. He doubled the dose of trazodone 50 mg on the night prior to presentation to calm his anxiety. An electrocardiogram revealed sinus rhythm at 60 beats per minute and second-degree Mobitz type 1 atrioventricular (AV) block with 5:4 AV conduction. Results of basic metabolic panel, thyroid-stimulating hormone, and chest radiograph were normal. A transthoracic echocardiogram revealed aortic valve sclerosis. We tested for Lyme disease given his history of hunting in the woods 8 months prior to presentation, but the titer was negative. Trazodone and omeprazole were discontinued. By the 3rd day of medication discontinuation, all symptoms had resolved and the frequency of second-degree AV Mobitz type 1 AV block had decreased to once per hour. Conclusions: Due diligence and meticulous attention to detail needs to be exercised to uncover drug interactions as potential causes of lethal and nonlethal patient symptomatology, as in this case of syncope caused by concomitant use of trazodone and a widely prescribed medication, omeprazole. PMID:26017199

Dietary Quercetin Reduces Chemotherapy-Induced Fatigue in Mice

PubMed Central

Mahoney, Sara E.; Davis, J. Mark; Murphy, E. Angela; McClellan, Jamie L.; Pena, Marjory M.

2014-01-01

Purpose While fatigue is the most commonly reported symptom of chemotherapy, there are currently no effective treatments for chemotherapy-induced fatigue (CIF). We used a mouse model to examine the benefits of quercetin on CIF as measured by voluntary wheel running activity and sought to determine whether quercetin may be associated with a decrease in inflammation and/or anemia. Methods Mice were assigned to 1 of 4 groups: placebo-vehicle (Plac-PBS), placebo-5-fluorouracil (Plac-5FU), quercetin-vehicle (Quer-PBS), or quercetin-5-fluorouracil (Quer-5FU). All mice were given a daily injection of either 60 mg/kg of 5-FU or phosphate buffered saline (PBS) for 5 days. Quercetin (0.02%) treatment was administered in the food 3 days prior to 5-FU administration and for the duration of the experiment (ie, days −2 to 14). A second group of mice was sacrificed at 5 and 14 days post initial injection for assessment of monocyte chemoattractant protein-1 (MCP-1) and anemia. Results Voluntary wheel running was reduced in both the Plac-5FU and Quer-5FU groups following 5-FU injection (P < .05). However, the Quer-5FU group recovered to baseline levels by approximately day 7, whereas the Plac-5FU group remained suppressed. MCP-1 was significantly elevated at 14 days in Plac-5FU (P < .001), but no changes were seen with Quer-5FU. Treatment with 5-FU resulted in anemia at both 5 days and 14 days; however, quercetin blocked this effect at 14 days (P < .001). Conclusion These results demonstrate the beneficial effect of quercetin on improving recovery of voluntary physical activity following 5-FU treatment, which may be linked to a decrease in inflammation and anemia. PMID:24626097

Pharmacological dissection of the cellular mechanisms associated to the spontaneous and the mechanically stimulated ATP release by mesentery endothelial cells: roles of thrombin and TRPV.

PubMed

Verónica Donoso, M; Hernández, Felipe; Villalón, Tania; Acuña-Castillo, Claudio; Pablo Huidobro-Toro, J

2018-06-01

Endothelial cells participate in extracellular ATP release elicited by mechanosensors. To characterize the dynamic interactions between mechanical and chemical factors that modulate ATP secretion by the endothelium, we assessed and compared the mechanisms participating in the spontaneous (basal) and mechanically stimulated secretion using primary cultures of rat mesentery endothelial cells. ATP/metabolites were determined in the cell media prior to (basal) and after cell media displacement or a picospritzer buffer puff used as mechanical stimuli. Mechanical stimulation increased extracellular ATP that peaked within 1 min, and decayed to basal values in 10 min. Interruption of the vesicular transport route consistently blocked the spontaneous ATP secretion. Cells maintained in media lacking external Ca 2+ elicited a spontaneous rise of extracellular ATP and adenosine, but failed to elicit a further extracellular ATP secretion following mechanical stimulation. 2-APB, a TRPV agonist, increased the spontaneous ATP secretion, but reduced the mechanical stimulation-induced nucleotide release. Pannexin1 or connexin blockers and gadolinium, a Piezo1 blocker, reduced the mechanically induced ATP release without altering spontaneous nucleotide levels. Moreover, thrombin or related agonists increased extracellular ATP secretion elicited by mechanical stimulation, without modifying spontaneous release. In sum, present results allow inferring that the spontaneous, extracellular nucleotide secretion is essentially mediated by ATP containing vesicles, while the mechanically induced secretion occurs essentially by connexin or pannexin1 hemichannel ATP transport, a finding fully supported by results from Panx1 -/- rodents. Only the latter component is modulated by thrombin and related receptor agonists, highlighting a novel endothelium-smooth muscle signaling role of this anticoagulant.

Nanoporous polymeric nanofibers based on selectively etched PS-b-PDMS block copolymers.

PubMed

Demirel, Gokcen B; Buyukserin, Fatih; Morris, Michael A; Demirel, Gokhan

2012-01-01

One-dimensional nanoporous polymeric nanofibers have been fabricated within an anodic aluminum oxide (AAO) membrane by a facile approach based on selective etching of poly(dimethylsiloxane) (PDMS) domains in polystyrene-block-poly(dimethylsiloxane) (PS-b-PDMS) block copolymers that had been formed within the AAO template. It was observed that prior to etching, the well-ordered PS-b-PDMS nanofibers are solid and do not have any porosity. The postetched PS nanofibers, on the other hand, had a highly porous structure having about 20-50 nm pore size. The nanoporous polymeric fibers were also employed as a drug carrier for the native, continuous, and pulsatile drug release using Rhodamine B (RB) as a model drug. These studies showed that enhanced drug release and tunable drug dosage can be achieved by using ultrasound irradiation. © 2011 American Chemical Society

Development and evaluation of a blocking enzyme-linked immunosorbent assay and virus neutralization assay to detect antibodies to viral hemorrhagic septicemia virus

USGS Publications Warehouse

Wilson, Anna; Goldberg, Tony; Marcquenski, Susan; Olson, Wendy; Goetz, Frederick; Hershberger, Paul; Hart, Lucas M.; Toohey-Kurth, Kathy

2014-01-01

Viral hemorrhagic septicemia virus (VHSV) is a target of surveillance by many state and federal agencies in the United States. Currently, the detection of VHSV relies on virus isolation, which is lethal to fish and indicates only the current infection status. A serological method is required to ascertain prior exposure. Here, we report two serologic tests for VHSV that are nonlethal, rapid, and species independent, a virus neutralization (VN) assay and a blocking enzyme-linked immunosorbent assay (ELISA). The results show that the VN assay had a specificity of 100% and sensitivity of 42.9%; the anti-nucleocapsid-blocking ELISA detected nonneutralizing VHSV antibodies at a specificity of 88.2% and a sensitivity of 96.4%. The VN assay and ELISA are valuable tools for assessing exposure to VHSV.

Construction of chiral ligand exchange capillary electrochromatography for d,l-amino acids enantioseparation and its application in glutaminase kinetics study.

PubMed

Zhao, Liping; Qiao, Juan; Zhang, Ke; Li, Dan; Zhang, Hongyi; Qi, Li

2018-05-04

A chiral ligand exchange capillary electrochromatography (CLE-CEC) protocol was designed and implemented for d,l-amino acids enantioseparation with poly(maleic anhydride-styrene-methacryloyl-l-arginine methyl ester) as the coating. The block copolymer was synthesized through the reversible addition fragmentation chain transfer reaction. In the constructed CLE-CEC system, poly (methacryloyl-l-arginine methyl ester) moiety of the block copolymer played the role as the immobilized chiral ligand and Zn (II) was used as the central ion. Key factors, including pH of buffer solution, ratio of Zn (II) to ligands, the mass ratio of monomers in the block copolymer, which affect the enantioresolution were investigated. Comparing with the bare capillary, the CLE-CEC enantioresolution was enhanced greatly with the coating one. 5 Pairs of d,l-amino acids enantiomers obtained baseline separation with 5 pairs partly separated. The mechanism of enhancement enantioresolution of the developed CLE-CEC system was explored briefly. Further, good linearities were achieved in the range of 25.0 μM-5.0 mM for quantitative analysis of d-glutamine (r 2  = 0.997) and l-glutamine (r 2  = 0.991). Moreover, the proposed CLE-CEC assay was successfully applied in the kinetics study of glutaminase by using l-glutamine as the substrate. Copyright © 2018 Elsevier B.V. All rights reserved.

Sympathetic blocks for the treatment of complex regional pain syndrome: A case series.

PubMed

Gungor, Semih; Aiyer, Rohit; Baykoca, Buse

2018-05-01

To present the successful treatment of complex regional pain syndrome type -1 utilizing sympathetic blocks. Severe pain interfering with activities of daily living and temporary disability secondary to complex regional pain syndrome. Complex regional pain syndrome type-1 with involvement of lower extremity (2 patients), and upper extremity (1 patient). We report the management of 3 patients with diagnosis of complex regional pain syndrome type-1 by early institution of sympathetic blocks for diagnostic and therapeutic purposes. All 3 patients were able to tolerate physical therapy only after adequate pain relief had been achieved with institution of sympathetic blocks. All 3 patients responded very favorably to sympathetic blocks with dramatic reversal of pathology. All patients reported almost complete resolution of pain, symptoms, and signs within 6 months duration after diagnosis of complex regional pain syndrome. All 3 patients were able to wean their pain medications and achieve normal activities of daily living without any significant limitations. All patients were able to return to full-time employment. Treatment options are limited and there is lack of high quality research regarding the efficacy of sympathetic blocks in the treatment of complex regional pain syndrome. As presented in this case series, sympathetic blocks maybe very effective in the treatment of complex regional pain syndrome in a subset of patients. Thus, early institution of sympathetic blocks should be considered in complex regional pain syndrome prior to physical therapy and consideration of more invasive pain management interventions.

Electrophysiologic and histologic observations of chronic atrioventricular block induced by closed-chest catheter desiccation with radiofrequency energy.

PubMed

Huang, S K; Bharati, S; Lev, M; Marcus, F I

1987-07-01

Direct-current or laser energy has been used to induce atrioventricular (AV) block, but certain complications associated with this type of energy have been reported. We have previously documented that radiofrequency (RF) energy can effectively and safely induce acute AV block in closed-chest dogs during the 4-7 days of follow-up. This study was undertaken to determine if the ablation was permanent and to define the chronic pathology and site of AV block. Complete AV block was successfully achieved in four dogs immediately after ablation with a bipolar "standard" RF output (750 kHz) delivered between the tip electrode of a standard 7F USCI catheter and an external patch electrode on the left lateral chest wall. During 2 months of follow-up, three dogs had persistent complete AV block with a stable escape rhythm; the other had persistent 2:1 AV block. Repeat His bundle recordings were performed at 2 months prior to sacrifice of the dogs. Supra-His AV block was noted in two dogs; His bundle potential could not be recorded in another two. Histologically, the damaged area was well delineated. In all animals, the AV node and, in some dogs, part of the His bundle were completely replaced by granulation tissue and/or cartilage. There was fatty infiltration and also chronic inflammatory cells around the lesions. Neither perforation, hemorrhage nor vacuolation was seen in the adjacent area. Thrombus was not present. It is concluded that RF energy can effectively achieve chronic AV block and produce well-circumscribed pathological lesions.

Precursor processes of human self-initiated action.

PubMed

Khalighinejad, Nima; Schurger, Aaron; Desantis, Andrea; Zmigrod, Leor; Haggard, Patrick

2018-01-15

A gradual buildup of electrical potential over motor areas precedes self-initiated movements. Recently, such "readiness potentials" (RPs) were attributed to stochastic fluctuations in neural activity. We developed a new experimental paradigm that operationalized self-initiated actions as endogenous 'skip' responses while waiting for target stimuli in a perceptual decision task. We compared these to a block of trials where participants could not choose when to skip, but were instead instructed to skip. Frequency and timing of motor action were therefore balanced across blocks, so that conditions differed only in how the timing of skip decisions was generated. We reasoned that across-trial variability of EEG could carry as much information about the source of skip decisions as the mean RP. EEG variability decreased more markedly prior to self-initiated compared to externally-triggered skip actions. This convergence suggests a consistent preparatory process prior to self-initiated action. A leaky stochastic accumulator model could reproduce this convergence given the additional assumption of a systematic decrease in input noise prior to self-initiated actions. Our results may provide a novel neurophysiological perspective on the topical debate regarding whether self-initiated actions arise from a deterministic neurocognitive process, or from neural stochasticity. We suggest that the key precursor of self-initiated action may manifest as a reduction in neural noise. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

The Serotonin 2C Receptor Agonist Lorcaserin Attenuates Intracranial Self-Stimulation and Blocks the Reward-Enhancing Effects of Nicotine.

PubMed

Zeeb, Fiona D; Higgins, Guy A; Fletcher, Paul J

2015-07-15

Lorcaserin, a serotonin (5-hydroxytryptamine, 5-HT) 2C receptor agonist, was recently approved for the treatment of obesity. We previously suggested that 5-HT2C receptor agonists affect reward processes and reduce the rewarding effects of drugs of abuse. Here, we determined whether lorcaserin (1) decreases responding for brain stimulation reward (BSR) and (2) prevents nicotine from enhancing the efficacy of BSR. Rats were trained on the intracranial self-stimulation (ICSS) paradigm to nosepoke for BSR of either the dorsal raphé nucleus or left medial forebrain bundle. In Experiment 1, lorcaserin (0.3-1.0 mg/kg) dose-dependently reduced the efficacy of BSR. This effect was blocked by prior administration of the 5-HT2C receptor antagonist SB242084. In Experiment 2, separate groups of rats received saline or nicotine (0.4 mg/kg) for eight sessions prior to testing. Although thresholds were unaltered in saline-treated rats, nicotine reduced reward thresholds. An injection of lorcaserin (0.3 mg/kg) prior to nicotine prevented the reward-enhancing effect of nicotine across multiple test sessions. These results demonstrated that lorcaserin reduces the rewarding value of BSR and also prevents nicotine from facilitating ICSS. Hence, lorcaserin may be effective in treating psychiatric disorders, including obesity and nicotine addiction, by reducing the value of food or drug rewards.

Resilience and post-traumatic stress disorder in the acute aftermath of rape: a comparative analysis of adolescents versus adults.

PubMed

van der Walt, Lydia; Suliman, Sharain; Martin, Lindi; Lammers, Kees; Seedat, Soraya

2014-01-01

Rape trauma contributes significantly to the mental burden of disease, affecting resilience and vulnerabilities at every developmental life stage. Appropriate resilience-promoting strategies could potentially buffer or protect trauma-exposed individuals from psychopathology. This study aimed to assess and compare (using validated measuring instruments) resilience, post-traumatic stress disorder (PTSD) and other variables in the acute aftermath of rape, between adolescent and adult females and to assess associations with these variables. We conducted a comparative analysis of resilience, PTSD, prior trauma, demographic variables and psychiatric morbidity in 41 adolescent and 47 adult female rape survivors six weeks post-rape. We assessed the relationship of resilience to PTSD, demographic variables and prior trauma and investigated if resilience levels predicted PTSD after adjusting for prior trauma. We found no significant differences in resilience levels between the groups, but the adolescent PTSD rate (40%) was double that in adults (20%). In adults, a significant negative correlation was evident between resilience and PTSD symptoms scores. More knowledge of resilience versus stress susceptibility for PTSD throughout the lifespan is needed and can inform the development of more effective clinical assessment and resilience-promoting strategies.

Studies on the production of alkaline α-amylase from Bacillus subtilis CB-18.

PubMed

Nwokoro, Ogbonnaya; Anthonia, Odiase

2015-01-01

Amylases are among the main enzymes used in food and other industries. They hydrolyse starch molecules into polymers composing glucose units. Amylases have potential applications in a number of industrial processes including foods and pharmaceutical industries. Alkaline α-amylase has the potential of hydrolysing starch under alkaline pH and is useful in the starch and textile industries and as an ingredient of detergents. Amylases are produced from plants, however, microbial production processes have dominated applications in the industries. Optimization of microbial production processes can result in improved enzyme yields. Amylase activity was assayed by incubating the enzyme solution (0.5 ml) with 1% soluble starch (0.5 ml) in 0.1 M Tris/HCl buffer (pH 8.5). After 30 minutes, the reaction was stopped by the addition of 4 mL of 3,5-dinitrosalicylic acid (DNS) reagent then heated for 10 min in boiling water bath and cooled in a refrigerator. Absorbance readings were used to estimate the units of enzyme activity from glucose standard curve. Hydrolysed native starches from cassava, rice, corn, coco yam, maize and potato and soluble starch were adjusted to pH 8.5 prior to incubation with crude enzyme solution. Reducing sugars produced were therefore determined. The effect of pH on enzyme activity of the alkaline α-amylase was determined by using buffer solutions of different pH (potassium phosphate buffer, 6.0-7.0; Tris-HCl buffer 7.5 to 9.0 and carbonate/bicarbonate buffer, pH 9.5-11) for enzyme assay. The pH stability profile of the enzyme was determined by incubating 0.5 ml of α-amylase enzyme in 0.1 M Tris/HCl buffer (pH 8.5) and 0.5 ml of 1% (w/v) soluble starch (Merck) in 0.1 M Tris/HCl buffer (pH 8.5) for 3 h in various buffers. The effect of temperature on enzyme activity was studied by incubating 0.5 mL of the enzyme solution contained in the test tube and 0.5 mL of 1% soluble starch (Merck) solution prepared in 0.1 M Tris/HCl buffer (pH 8.5) for 3 h at various temperatures (25, 30, 35, 40, 45, 50, 55 and 60°C) in a thermo static water bath. The reactions were stopped by adding DNS reagent. The enzyme activity was therefore determined. Thermal stability was studied by incubating 0.5 ml of enzyme solution in 0.1 M Tris/HCl buffer (pH 8.5) and 0.5 ml of 1% (w/v) soluble starch (Merck) in 0.1 M Tris/HCl buffer (pH 8.5) for 3 h at various temperatures (20, 30, 40, 50, 60 and 70°C) for 60 min. The enzyme displayed optimal activity at pH 8.0 at which it produced maximum specific activity of 34.3 units/mg protein. Maximum stability was at pH 8.0 to 9.0. Maximum activity was observed at temperature of 50°C while thermo stability of the enzyme was observed at 40-50°C. The enzyme displayed a wide range of activities on starch and caused the release of 5.86, 4.75, 5.98, 3.44, 3.96, 8.84 mg/mL reducing sugar from cassava, potato, cocoyam, corn, rice and soluble starch respectively. This investigation reports some biochemical characterization of alkaline α-amylase from Bacillus subtilis CB-18. The substrate specificities of this enzyme on various starches suggested that the alkaline α-amylase enzyme had combined activities on raw and soluble starch.

A comparison of the fascia iliaca block to the lumbar plexus block in providing analgesia following arthroscopic hip surgery: A randomized controlled clinical trial.

PubMed

Badiola, Ignacio; Liu, Jiabin; Huang, Stephanie; Kelly, John D; Elkassabany, Nabil

2018-05-31

This randomized controlled single blinded clinical trial compared the fascia iliaca block (FIB) and the lumbar plexus block (LPB) in patients with moderate to severe pain following hip arthroscopic surgery. Single blinded randomized trial. Postoperative recovery area, postoperative days 0 and 1. Fifty patients undergoing hip arthroscopy were approached in the Post Anesthesia Care Unit (PACU) if they had moderate to severe pain (defined as > or equal 4/10 on the numeric rating scale). Twenty-five patients were allocated to the FIB and twenty-five patients to the LPB. Fascia iliaca block or lumbar plexus block. A blinded observer recorded pain scores just prior to the block, 15 min following the block (primary endpoint), and then every 15 min for 2 h (or until the patient was discharged). Total PACU time and opioid use were recorded. Pain scores and analgesic use on postoperative day (POD) 0, and POD 1 were recorded. At 24 h post block the Quality of Recovery 9 questionnaire was administered. The mean pre-block pain scores were comparable between the two groups (P = 0.689). There was no difference in mean post block pain scores between the two groups at 15 min (P = 0.054). In the PACU patients who underwent a LPB consumed less opioids compared to FIB patients (P = 0.02), however no differences were noted between the two groups in PACU length of stay, or POD 0 or 1 opioid use. A fascia iliaca block is not inferior to a lumbar plexus block in reducing PACU pain scores in patients with moderate to severe pain following hip arthroscopic surgery and is a viable option to help manage postoperative pain following hip arthroscopic surgery. Copyright © 2018. Published by Elsevier Inc.

Strategic retrieval processing and the impact of knowing when a memory was first created.

PubMed

Roberts, J S; Tsivilis, D; Mayes, A R

2014-04-01

Retrieval orientation refers to a process where participants strategically alter how a memory cue is processed in response to different task demands. In the present study we explored whether retrieval orientation is influenced by knowing when an old stimulus was first encoded. Participants completed separate remember/know test blocks for old items from a recent delay (40min) and old items from a remote delay (48h). Manipulations at encoding ensured that performance levels were matched between these two blocks, thus avoiding confounds with differences in retrieval effort. Importantly, a third test block comprised old items from both delays randomly intermixed. As the nature of the old items varies unpredictably in the mixed block, it should not be possibly to adopt a specific retrieval orientation and the mixed block therefore acts as a control condition. Participants saw the words "mixed," "recent" or "remote" prior to each test block. Comparing ERPs from the recent and remote blocks permitted an investigation of whether participants alter their retrieval orientation in response to the specific length of the retention interval. Comparing ERPs from the pure (recent and remote) test blocks to ERPs from the mixed block permitted an investigation of whether delay information per se led to differences in retrieval strategy. Analysis of the ERP data found no differences between the recent and remote blocks. However, ERPs from these pure blocks were significantly less positive than ERPs from the mixed block from 200ms towards the end of the epoch. The findings suggest that the delay information was useful in a general sense and encouraged retrieval strategies distinct from those engaged in the mixed block. We speculate that such strategies might relate to whether or not the retrieval search is specific and constrained and/or whether processes that serve to reinstate the original encoding context are engaged. Copyright © 2014 Elsevier Inc. All rights reserved.

Do residents’ perceptions of being well-placed and objective presence of local amenities match? A case study in West Central Scotland, UK

PubMed Central

2013-01-01

Background Recently there has been growing interest in how neighbourhood features, such as the provision of local facilities and amenities, influence residents’ health and well-being. Prior research has measured amenity provision through subjective measures (surveying residents’ perceptions) or objective (GIS mapping of distance) methods. The latter may provide a more accurate measure of physical access, but residents may not use local amenities if they do not perceive them as ‘local’. We believe both subjective and objective measures should be explored, and use West Central Scotland data to investigate correspondence between residents’ subjective assessments of how well-placed they are for everyday amenities (food stores, primary and secondary schools, libraries, pharmacies, public recreation), and objective GIS-modelled measures, and examine correspondence by various sub-groups. Methods ArcMap was used to map the postal locations of ‘Transport, Health and Well-being 2010 Study’ respondents (n = 1760), and the six amenities, and the presence/absence of each of them within various straight-line and network buffers around respondents’ homes was recorded. SPSS was used to investigate whether objective presence of an amenity within a specified buffer was perceived by a respondent as being well-placed for that amenity. Kappa statistics were used to test agreement between measures for all respondents, and by sex, age, social class, area deprivation, car ownership, dog ownership, walking in the local area, and years lived in current home. Results In general, there was poor agreement (Kappa <0.20) between perceptions of being well-placed for each facility and objective presence, within 800 m and 1000 m straight-line and network buffers, with the exception of pharmacies (at 1000 m straight-line) (Kappa: 0.21). Results varied between respondent sub-groups, with some showing better agreement than others. Amongst sub-groups, at 800 m straight-line buffers, the highest correspondence between subjective and objective measures was for pharmacies and primary schools, and at 1000 m, for pharmacies, primary schools and libraries. For road network buffers under 1000 m, agreement was generally poor. Conclusion Respondents did not necessarily regard themselves as well-placed for specific amenities when these amenities were present within specified boundaries around their homes, with some exceptions; the picture is not clear-cut with varying findings between different amenities, buffers, and sub-groups. PMID:23651734

Growth and characterization of AlGaN/GaN/AlGaN double-heterojunction high-electron-mobility transistors on 100-mm Si(111) using ammonia-molecular beam epitaxy

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

Ravikiran, L.; Radhakrishnan, K., E-mail: ERADHA@ntu.edu.sg; Yiding, Lin

2015-01-14

To improve the confinement of two-dimensional electron gas (2DEG) in AlGaN/GaN high electron mobility transistor (HEMT) heterostructures, AlGaN/GaN/AlGaN double heterojunction HEMT (DH-HEMT) heterostructures were grown using ammonia-MBE on 100-mm Si substrate. Prior to the growth, single heterojunction HEMT (SH-HEMT) and DH-HEMT heterostructures were simulated using Poisson-Schrödinger equations. From simulations, an AlGaN buffer with “Al” mole fraction of 10% in the DH-HEMT was identified to result in both higher 2DEG concentration (∼10{sup 13 }cm{sup −2}) and improved 2DEG confinement in the channel. Hence, this composition was considered for the growth of the buffer in the DH-HEMT heterostructure. Hall measurements showed a roommore » temperature 2DEG mobility of 1510 cm{sup 2}/V.s and a sheet carrier concentration (n{sub s}) of 0.97 × 10{sup 13 }cm{sup −2} for the DH-HEMT structure, while they are 1310 cm{sup 2}/V.s and 1.09 × 10{sup 13 }cm{sup −2}, respectively, for the SH-HEMT. Capacitance-voltage measurements confirmed the improvement in the confinement of 2DEG in the DH-HEMT heterostructure, which helped in the enhancement of its room temperature mobility. DH-HEMT showed 3 times higher buffer break-down voltage compared to SH-HEMT, while both devices showed almost similar drain current density. Small signal RF measurements on the DH-HEMT showed a unity current-gain cut-off frequency (f{sub T}) and maximum oscillation frequency (f{sub max}) of 22 and 25 GHz, respectively. Thus, overall, DH-HEMT heterostructure was found to be advantageous due to its higher buffer break-down voltages compared to SH-HEMT heterostructure.« less

Chronic lactate supplementation does not improve blood buffering capacity and repeated high-intensity exercise.

PubMed

Oliveira, L F; de Salles Painelli, V; Nemezio, K; Gonçalves, L S; Yamaguchi, G; Saunders, B; Gualano, B; Artioli, G G

2017-11-01

Since there is conflicting data on the buffering and ergogenic properties of calcium lactate (CL), we investigated the effect of chronic CL supplementation on blood pH, bicarbonate, and high-intensity intermittent exercise performance. Sodium bicarbonate (SB) was used as a positive control. Eighteen athletes participated in this double-blind, placebo-controlled, crossover, fully counterbalanced study. All participants underwent three different treatments: placebo (PL), CL, and SB. The dose was identical in all conditions: 500 mg/kg BM divided into four daily individual doses of 125 mg/kg BM, for five consecutive days, followed by a 2-7-day washout period. On the fifth day of supplementation, individuals undertook four 30-s Wingate bouts for upper body with 3-min recovery between bouts. Total mechanical work (TMW) for the overall protocol and for the initial (1st+2nd) and final (3rd+4th) bouts was determined at each session. Blood pH, bicarbonate, and lactate levels were determined at rest, immediately and 5 min after exercise. CL supplementation did not affect performance (P > 0.05 for the overall TMW as well for initial and final bouts), nor did it affect blood bicarbonate and pH prior to exercise. SB supplementation improved performance by 2.9% for overall TMW (P = 0.02) and 5.9% in the 3rd+4th bouts (P = 0001). Compared to the control session, SB also promoted higher increases in blood bicarbonate than CL and PL (+0.03 ± 0.04 vs +0.009 ± 0.02 and +0.01 ± 0.03, respectively). CL supplementation was not capable of enhancing high-intensity intermittent performance or changing extracellular buffering capacity challenging the notion that this dietary supplement is an effective buffering agent. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Evaluation of the effect of storage condition on cell extraction and flow cytometric analysis from intestinal biopsies.

PubMed

Wildenberg, Manon E; Duijvestein, Marjolijn; Westera, Liset; van Viegen, Tanja; Buskens, Christianne J; van der Bilt, Jarmila D W; Stitt, Larry; Jairath, Vipul; Feagan, Brian G; Vande Casteele, Niels

2018-06-01

Flow cytometric (FC) analysis of intestinal tissue biopsies requires prompt cell isolation and processing to prevent cell death and generate valid data. We examined the effect of storage conditions prior to cell isolation and FC on viable cell yield and the proportions of immune cell phenotypes from intestinal biopsies. Biopsies (N = 224) from inflamed or non-inflamed ileal and/or colonic tissue from three patients with Crohn's disease were processed and analyzed immediately in duplicate, or stored under different conditions. Cells were isolated and stained for specific markers, followed by FC. Decreased mean live CD45+ cell counts were observed after storage of biopsies at -80 °C dimethyl sulfoxide (DMSO)/citrate buffer compared with immediate processing (1794.3 vs. 19,672.7; p = 0.006]). A non-significant decrease in CD45+ live cell count occurred after storage at -20 °C in DMSO/citrate buffer and cell yield was adequate for subsequent analysis. CD3+ cell proportions were significantly lower after storage at 4 °C in complete medium for 48 h compared with immediate analysis. Mean CD14+ cell proportions were significantly higher after storage of biopsies at -80 °C in DMSO/citrate buffer compared with immediate analysis (2.61% vs. 1.31%, p = 0.007). CD4+, CD8+ and CD4+/CD8+ cell proportions were unaffected by storage condition. Storage of intestinal tissue biopsies at -20 °C in DMSO/citrate buffer for up to 48 h resulted in sufficient viable cell yield for FC analysis without affecting subsequent marker-positive cell proportions. These findings support the potential shipping and storage of intestinal biopsies for centralized FC analysis in multicenter clinical trials. Copyright © 2018 Elsevier B.V. All rights reserved.

Comparison of the post-operative analgesic effect of paravertebral block, pectoral nerve block and local infiltration in patients undergoing modified radical mastectomy: A randomised double-blind trial

PubMed Central

Syal, Kartik; Chandel, Ankita

2017-01-01

Background and Aims: Paravertebral block, pectoral nerve (Pecs) block and wound infiltration are three modalities for post-operative analgesia following breast surgery. This study compares the analgesic efficacy of these techniques for post-operative analgesia. Methods: Sixty-five patients with American Society of Anesthesiologists’ physical status 1 or 2 undergoing modified radical mastectomy with axillary dissection were recruited for the study. All patients received 21 mL 0.5% bupivacaine with adrenaline in the technique which was performed at the end of the surgery prior to extubation. Patients in Group 1 (local anaesthetic [LA], n = 22) received infiltration at the incision site after surgery, Group 2 patients (paravertebral block [PVB], n = 22) received ultrasound-guided ipsilateral paravertebral block while Group 3 patients [PECT] (n = 21) received ultrasound-guided ipsilateral Pecs blocks I and II. Patients were evaluated for pain scores at 0, 2, 4, 6, 12 and 24 h, duration of post-operative analgesia and rescue analgesic doses required. Non-normally distributed data were analysed using the Kruskal-Wallis test and Analysis of variance for normal distribution. Results: The post-operative visual analogue scale scores were lower in PVB group compared with others at 0, 2, 4, 12 and 24 h (P < 0.05). Mean duration of analgesia was significantly prolonged in PVB group (P < 0.001) with lesser rescue analgesic consumption up to 24 h. Conclusion: Ultrasound-guided paravertebral block reduces post-operative pain scores, prolongs the duration of analgesia and decreases demands for rescue analgesics in the first 24 h of post-operative period compared to ultrasound-guided Pecs block and local infiltration block. PMID:28890559

Comparison of the post-operative analgesic effect of paravertebral block, pectoral nerve block and local infiltration in patients undergoing modified radical mastectomy: A randomised double-blind trial.

PubMed

Syal, Kartik; Chandel, Ankita

2017-08-01

Paravertebral block, pectoral nerve (Pecs) block and wound infiltration are three modalities for post-operative analgesia following breast surgery. This study compares the analgesic efficacy of these techniques for post-operative analgesia. Sixty-five patients with American Society of Anesthesiologists' physical status 1 or 2 undergoing modified radical mastectomy with axillary dissection were recruited for the study. All patients received 21 mL 0.5% bupivacaine with adrenaline in the technique which was performed at the end of the surgery prior to extubation. Patients in Group 1 (local anaesthetic [LA], n = 22) received infiltration at the incision site after surgery, Group 2 patients (paravertebral block [PVB], n = 22) received ultrasound-guided ipsilateral paravertebral block while Group 3 patients [PECT] ( n = 21) received ultrasound-guided ipsilateral Pecs blocks I and II. Patients were evaluated for pain scores at 0, 2, 4, 6, 12 and 24 h, duration of post-operative analgesia and rescue analgesic doses required. Non-normally distributed data were analysed using the Kruskal-Wallis test and Analysis of variance for normal distribution. The post-operative visual analogue scale scores were lower in PVB group compared with others at 0, 2, 4, 12 and 24 h ( P < 0.05). Mean duration of analgesia was significantly prolonged in PVB group ( P < 0.001) with lesser rescue analgesic consumption up to 24 h. Ultrasound-guided paravertebral block reduces post-operative pain scores, prolongs the duration of analgesia and decreases demands for rescue analgesics in the first 24 h of post-operative period compared to ultrasound-guided Pecs block and local infiltration block.

The effect of prolonged exposure to 750 C air on the tribological performance of PM212

NASA Technical Reports Server (NTRS)

Bemis, Kirk; Bogdanski, Michael S.; Dellacorte, Christopher; Sliney, Harold E.

1994-01-01

The effect of prolonged exposure to 750 C air on the tribological performance and dimensional stability of PM212, a high temperature, self-lubricating composite, is studied. PM212, by weight, contains 70 percent metal-bonded Cr3C2, 15 percent BaF2/CaF2 eutectic, and 15 percent silver. Rub blocks were fabricated from PM212 by cold isostatic pressing followed by sintering. Prior to tribo-testing, the rub blocks were exposed to 750 C air for periods ranging from 100 to 1000 hours. Then, the rub blocks were slid against nickel-based superalloy disks in a double-rub-block tribometer in air under a 66 N load at temperatures from 25 to 750 C with a sliding velocity of 0.36 m/s. Unexposed rub blocks were tested for baseline comparison. Friction coefficients ranged from 0.24 to 0.37 for the unexposed rub blocks and from 0.32 to 0.56 for the exposed ones. Wear for both the composite blocks and superalloy disks was typically in the moderate to low range of 10(exp -5) to 10(exp -6) mm(exp 3)/N-m. Friction and wear data were similar for the rub blocks exposed for 100, 500, and 1000 hours. Prolonged exposure to 750 C air increased friction and wear of the PM212 rub blocks at room temperature, but their triboperformance remained unaffected at higher temperatures, probably due to the formation of lubricious metal oxides. Dimensional stability of the composite was studied by exposing specimens of varying thicknesses for 500 hours in air at 750 C. Block thicknesses were found to increase with increased exposure time until steady state was reached after 100 hours of exposure, probably due to oxidation.

Horizontal sliding of kilometre-scale hot spring area during the 2016 Kumamoto earthquake

PubMed Central

Tsuji, Takeshi; Ishibashi, Jun’ichiro; Ishitsuka, Kazuya; Kamata, Ryuichi

2017-01-01

We report horizontal sliding of the kilometre-scale geologic block under the Aso hot springs (Uchinomaki area) caused by vibrations from the 2016 Kumamoto earthquake (Mw 7.0). Direct borehole observations demonstrate the sliding along the horizontal geological formation at ~50 m depth, which is where the shallowest hydrothermal reservoir developed. Owing to >1 m northwest movement of the geologic block, as shown by differential interferometric synthetic aperture radar (DInSAR), extensional open fissures were generated at the southeastern edge of the horizontal sliding block, and compressional deformation and spontaneous fluid emission from wells were observed at the northwestern edge of the block. The temporal and spatial variation of the hot spring supply during the earthquake can be explained by the horizontal sliding and borehole failures. Because there was no strain accumulation around the hot spring area prior to the earthquake and gravitational instability could be ignored, the horizontal sliding along the low-frictional formation was likely caused by seismic forces from the remote earthquake. The insights derived from our field-scale observations may assist further research into geologic block sliding in horizontal geological formations. PMID:28218298

40 CFR 63.482 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... chloroprene (2-chloro-1,3-butadiene). The free radical emulsion process is generally used to produce neoprene... authority (§ 63.2) Plant site (§ 63.101) Potential to emit (§ 63.2) Pressure release (§ 63.161) Primary fuel... to as campaign plants or blocked operations. Front-end refers to the unit operations in an EPPU prior...

31 CFR 515.531 - Payment of certain checks and drafts.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Payment of certain checks and drafts... Licenses, Authorizations, and Statements of Licensing Policy § 515.531 Payment of certain checks and drafts... blocked accounts with such banking institution: (1) Of checks and drafts drawn or issued prior to the...

31 CFR 535.531 - Payment of certain checks and drafts.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Payment of certain checks and drafts... Licenses, Authorizations and Statements of Licensing Policy § 535.531 Payment of certain checks and drafts... from blocked accounts with such banking institution of checks and drafts drawn or issued prior to the...

31 CFR 535.531 - Payment of certain checks and drafts.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Payment of certain checks and drafts... Licenses, Authorizations and Statements of Licensing Policy § 535.531 Payment of certain checks and drafts... from blocked accounts with such banking institution of checks and drafts drawn or issued prior to the...

31 CFR 515.531 - Payment of certain checks and drafts.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Payment of certain checks and drafts... Licenses, Authorizations, and Statements of Licensing Policy § 515.531 Payment of certain checks and drafts... blocked accounts with such banking institution: (1) Of checks and drafts drawn or issued prior to the...

31 CFR 515.531 - Payment of certain checks and drafts.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Payment of certain checks and drafts... Licenses, Authorizations, and Statements of Licensing Policy § 515.531 Payment of certain checks and drafts... blocked accounts with such banking institution: (1) Of checks and drafts drawn or issued prior to the...

31 CFR 535.531 - Payment of certain checks and drafts.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Payment of certain checks and drafts... Licenses, Authorizations and Statements of Licensing Policy § 535.531 Payment of certain checks and drafts... from blocked accounts with such banking institution of checks and drafts drawn or issued prior to the...

31 CFR 535.531 - Payment of certain checks and drafts.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Payment of certain checks and drafts... Licenses, Authorizations and Statements of Licensing Policy § 535.531 Payment of certain checks and drafts... from blocked accounts with such banking institution of checks and drafts drawn or issued prior to the...

31 CFR 515.531 - Payment of certain checks and drafts.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Payment of certain checks and drafts... Licenses, Authorizations, and Statements of Licensing Policy § 515.531 Payment of certain checks and drafts... blocked accounts with such banking institution: (1) Of checks and drafts drawn or issued prior to the...

31 CFR 515.531 - Payment of certain checks and drafts.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Payment of certain checks and drafts. 515.531 Section 515.531 Money and Finance: Treasury Regulations Relating to Money and Finance... blocked accounts with such banking institution: (1) Of checks and drafts drawn or issued prior to the...

How Should Intelligent Tutoring Systems Sequence Multiple Graphical Representations of Fractions? A Multi-Methods Study

ERIC Educational Resources Information Center

Rau, M. A.; Aleven, V.; Rummel, N.; Pardos, Z.

2014-01-01

Providing learners with multiple representations of learning content has been shown to enhance learning outcomes. When multiple representations are presented across consecutive problems, we have to decide in what sequence to present them. Prior research has demonstrated that interleaving "tasks types" (as opposed to blocking them) can…

Power Analysis for Anticipated Non-Response in Randomized Block Designs

ERIC Educational Resources Information Center

Pustejovsky, James E.

2011-01-01

Recent guidance on the treatment of missing data in experiments advocates the use of sensitivity analysis and worst-case bounds analysis for addressing non-ignorable missing data mechanisms; moreover, plans for the analysis of missing data should be specified prior to data collection (Puma et al., 2009). While these authors recommend only that…

Impact of curd milling on the quality traits of starter-free pasteurized Queso Fresco

USDA-ARS?s Scientific Manuscript database

Manufacture of Queso Fresco (QF), a high moisture fresh Hispanic-style cheese that is very popular in the Americas, varies from country to country with many manufacturers fine milling the curd prior to forming the cheese block to ensure its crumbly nature. As this traditional step increases the ris...

The Effectiveness of Remotely Piloted Aircraft in a Permissive Hunter-Killer Scenario

DTIC Science & Technology

2014-01-01

APY -8, Lynx Block 20. 20 Specific Scenario In our scenario, prior intelligence has indicated that the target is likely to emerge from hiding...an additional 5 sec. must be taken to transfer (digitally) the target geolocation data to the strike platform. (Unlike in Case 1, it was not

Teacher Education for Social Change: Transforming a Content Methods Course Block

ERIC Educational Resources Information Center

Ritchie, Scott; An, Sohyun; Cone, Neporcha; Bullock, Patricia

2013-01-01

This article analyzes data from a qualitative practitioner-research case study in which four university faculty members attempted to disrupt the hegemonic domestication of candidates enrolled in an undergraduate teacher education program. During the semester prior to their student teaching, 16 candidates at a large public university in the…

Role of block copolymer-micelle nanocomposites in dye-bovine serum albumin binding: a combined experimental and molecular docking study.

PubMed

Manna, Anamika; Chakravorti, Sankar

2013-02-02

The role of a nanocomposite (NC), composed of intercalation of the diblock copolymer polyethylene-b-polyethylene glycol (PE-b-PEG) with the anionic surfactant sodium dodecyl sulphate (SDS), on the binding characteristics of bovine serum albumin (BSA) with a dye (1,8-naphthalimide, NAPMD) compared to the interaction between the same players in aqueous solution has been examined comprehensively in this paper. Static quenching due to complex formation in both NC medium and in buffer solution has been inferred on the basis of considerable changes in the absorption spectra of BSA on addition of NAPMD, of which the interaction is found to be stronger in NC medium. Temperature dependent fluorescence data also confirm an effective static quenching and stronger binding of NAPMD with BSA in NC medium. Peptide chain unfolding and denaturing of BSA in NC medium have been confirmed from steady state and time-resolved emission and circular dichroism data. This exposes both the tyrosine and tryptophan moieties as a unique case. Increased energy transfer between NAPMD and the tryptophan residue in the unfolded form of BSA helps in the appearance of tyrosine fluorescence in NC medium by quenching the tryptophan band. Ionization of the hydroxyl group in the aromatic ring of the tyrosine residue by the PEG group present in the NC medium produces a downshift of the tyrosine fluorescence band. The use of site selective markers confirms that NAPMD is near tryptophan in Sudlow's site I in NC medium and in buffer solution it is away from tryptophan in Sudlow's site II. The theoretical docking studies also vindicate the results of binding of NAPMD with BSA in site I or site II in NC and buffer media, as observed from different emission experiments including the site selective markers study.

Rapid diagnosis of soybean mosaic virus N soybean by tissue-print immunoassay and DIBA in comparison to other serological methods.

PubMed

Ahangaran, A; Mohammadi, Gh Mosahebi; Habibi, M Koohi; Shahraeen, N; Khezri, S

2006-01-01

Soybean mosaic virus (SMV) is an important disease in soybean and is widely distributed in northern of Iran. SMV transmitted by soybean seed and detection of it is very important for disease management. In this study, several detection methods including DAS-ELISA, indirect-ELISA, tissue-print immunoassay (TPIA) and Dot immunobinding assay (DIBA) were optimized and compared with each other to identify the virus, using polyclonal antibody. For TPIA, nitrocellulose membrane was used to imprint fresh sections of healthy and infected plant materials, and for DIBA 10 microl of extracts was doted onto nitrocellulose membranes. Both membranes were incubated 1 hour in blocking buffer, and then incubated 2 h in 1:1000 dilution of IgG-conjugate. After incubation the membranes were washed three times with PBS-T buffer for 15 min. Then the membranes were incubated in substrate solution containing NBT/BCIP. After some minutes prints or blots of infected tissues turned dark violet, whereas prints or blots of healthy ones did not show any color changes. In some cases, substrate solution was Fast red, containing 0.2M Tris-HCl buffer and 2mM MgCl2, pH = 7.8, producing red color in infected prints or blots. Both methods are simple and TPIA is rapidly and easily applicable in the field. However, TPIA had some advantages over the others. TPIA is time-saving as there is no need for conventional sap extraction and also nitrocellulose membranes used for printing can be used in the field and stored for a long time or transported to another laboratory for process. These two methods can be used routinely for detection of SMV in many samples.

Nature and origin of the calcium asymmetry-arising during gravitropic response in etiolated pea epicotyls

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

Migliaccio, F.; Galston, A.W.

1987-10-01

Seven day old etiolated pea epicotyls were loaded symmetrically with /sup 3/H-indole 3-acetic acid (IAA) or /sup 45/Ca/sup 2 +/, then subjected to 1.5 hours of 1g gravistimulation. Epidermal peels taken from top and bottom surfaces after 90 minutes showed an increase in IAA on the lower side and of Ca/sup 2 +/ on the upper side. Inhibitors of IAA movement (TIBA, 9-hydroxyfluorene carboxylic acid) block the development of both IAA and Ca/sup 2 +/ asymmetries, but substances known to interfere with normal Ca/sup 2 +/ transport do not significantly alter either IAA or Ca/sup 2 +/ asymmetries. These substances,more » however, are active in modifying both Ca/sup 2 +/ uptake and efflux through oat and pea leaf protoplast membranes. The authors conclude that the /sup 45/Ca/sup 2 +/ fed to pea epicotyls occurs largely in the cell wall, and that auxin movement is primary and Ca/sup 2 +/ movement secondary in gravitropism. They hypothesize that apoplastic Ca/sup 2 +/ changes during the graviresponse because it is displaced by H/sup +/ secreted through auxin-induced proton release. This proposed mechanism is supported by localized pH experiments, in which filter paper soaked in various buffers was applied to one side of a carborundum-abraded epicotyls. Buffer at pH 3 increased calcium loss from the side to which it is applied, whereas pH 7 buffer decreases it. Moreover, 10 micromolar IAA and 1 micromolar fusicoccin, which promote H/sup +/ efflux, increase Ca/sup 2 +/ release from pea epicotyl segments, whereas cycloheximide, which inhibits H/sup +/ efflux, has the reverse effect.« less

Preventive Effects on Birth Outcomes: Buffering Impact of Maternal Stress, Depression, and Anxiety.

PubMed

Feinberg, Mark E; Jones, Damon E; Roettger, Michael E; Hostetler, Michelle L; Sakuma, Kari-Lyn; Paul, Ian M; Ehrenthal, Deborah B

2016-01-01

Although maternal stress, anxiety, and depression have been linked to negative birth outcomes, few studies have investigated preventive interventions targeting maternal mental health as a means of reducing such problems. This randomized controlled study examines whether Family Foundations (FF)-a transition to parenthood program for couples focused on promoting coparenting quality, with previously documented impact on maternal stress, depression, and anxiety-can buffer the negative effects of maternal mental health problems. To assess the effects of FF, we used a randomized block design with a sample of 259 expectant mothers assigned to FF or a control condition and analyzed using propensity score models. We examine two-way interactions of condition (intervention vs. control) with maternal mental health problems (financial stress, depression, and anxiety) on birth outcomes (birth weight, days in hospital for mothers and infants). For birth weight, we assess whether intervention effects depend on length of gestation by including a third interaction term. FF buffered (p < 0.05) the negative impact of maternal mental health problems on birth weight and both mother and infant length of post-partum hospital stay. For birth weight, assignment to FF was associated with higher birth weight for infants born before term. These results demonstrate that a psycho-educational program for couples focused on enhancing mutual coparental support, with preventive effects on maternal mental health, can reduce incidence of birth problems among women at elevated risk. Such improvements in birth outcomes could translate into substantial reductions in public and personal healthcare costs. Future work should assess mediating mechanisms of intervention impact and cost-benefit ratio of the intervention. The Family Foundations follow-up intervention study is currently registered with www.clinicaltrials.gov . The study identifier is NCT01907412.

An interdisciplinary study of the estuarine and coastal oceanography of Block Island Sound and adjacent New York coastal waters

NASA Technical Reports Server (NTRS)

Yost, E. (Principal Investigator)

1972-01-01

The author has identified the following significant results. The synoptic repetitive coverage of the multispectral imagery from the ERTS-1 satellite, when photographically reprocessed using the state-of-the-art techniques, has given indication of spectral differences in Block Island and adjacent New England waters which were heretofore unknown. Of particular interest was the possible detection of relatively small amounts of phytoplankton prior to the occurrence of the red tide in Massachusetts waters. Preparation of spatial and temporal hydrographic charts using ERTS-1 imagery and ground truth analysis will hopefully determine the environmental impact on New York coastal waters.

Factors influencing the immune response. III. The blocking effect of Corynebacterium parvum upon the induction of acquired immunological unresponsiveness to bovine serum albumin in the adult rabbit

PubMed Central

Pinckard, R. N.; Weir, D. M.; McBride, W. H.

1968-01-01

The intravenous injection of 10 mg aggregate-free, centrifuged bovine albumin into adult rabbits has been shown to induce an unresponsive state to bovine serum albumin (BSA) in the majority of rabbits. An intravenous injection of 15 mg of a heat-killed suspension of Corynebacterium parvum either 6 days prior to or simultaneously with centrifuged bovine albumin has been shown to significantly block the induction of unresponsiveness to BSA. Some effects of C. parvum upon the lymphoreticular tissues in the rabbit are reported. ImagesFig. 1Fig. 2 PMID:5301938

High Performance Compression of Science Data

NASA Technical Reports Server (NTRS)

Storer, James A.; Carpentieri, Bruno; Cohn, Martin

1994-01-01

Two papers make up the body of this report. One presents a single-pass adaptive vector quantization algorithm that learns a codebook of variable size and shape entries; the authors present experiments on a set of test images showing that with no training or prior knowledge of the data, for a given fidelity, the compression achieved typically equals or exceeds that of the JPEG standard. The second paper addresses motion compensation, one of the most effective techniques used in interframe data compression. A parallel block-matching algorithm for estimating interframe displacement of blocks with minimum error is presented. The algorithm is designed for a simple parallel architecture to process video in real time.

Cost-effective and rapid lysis of Saccharomyces cerevisiae cells for quantitative western blot analysis of proteins, including phosphorylated eIF2α.

PubMed

Lee, Su Jung; Ramesh, Rashmi; de Boor, Valerie; Gebler, Jan M; Silva, Richard C; Sattlegger, Evelyn

2017-09-01

The common method for liberating proteins from Saccharomyces cerevisiae cells involves mechanical cell disruption using glass beads and buffer containing inhibitors (protease, phosphatase and/or kinase inhibitors), followed by centrifugation to remove cell debris. This procedure requires the use of costly inhibitors and is laborious, in particular when many samples need to be processed. Also, enzymatic reactions can still occur during harvesting and cell breakage. As a result low-abundance and labile proteins may be degraded, and enzymes such as kinases and phosphatases may still modify proteins during and after cell lysis. We believe that our rapid sample preparation method helps overcome the above issues and offers the following advantages: (a) it is cost-effective, as no inhibitors and breaking buffer are needed; (b) cell breakage is fast (about 15 min) since it only involves a few steps; (c) the use of formaldehyde inactivates endogenous proteases prior to cell lysis, dramatically reducing the risk of protein degradation; (d) centrifugation steps only occur prior to cell lysis, circumventing the problem of losing protein complexes, in particular if cells were treated with formaldehyde intended to stabilize and capture large protein complexes; and (e) since formaldehyde has the potential to instantly terminate protein activity, this method also allows the study of enzymes in live cells, i.e. in their true physiological environment, such as the short-term effect of a drug on enzyme activity. Taken together, the rapid sample preparation procedure provides a more accurate snapshot of the cell's protein content at the time of harvesting. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Spatial disparity in the distribution of superfund sites in South Carolina: an ecological study.

PubMed

Burwell-Naney, Kristen; Zhang, Hongmei; Samantapudi, Ashok; Jiang, Chengsheng; Dalemarre, Laura; Rice, LaShanta; Williams, Edith; Wilson, Sacoby

2013-11-06

According to the US Environmental Protection Agency (EPA), Superfund is a federal government program implemented to clean up uncontrolled hazardous waste sites. Twenty-six sites in South Carolina (SC) have been included on the National Priorities List (NPL), which has serious human health and environmental implications. The purpose of this study was to assess spatial disparities in the distribution of Superfund sites in SC. The 2000 US census tract and block level data were used to generate population characteristics, which included race/ethnicity, socioeconomic status (SES), education, home ownership, and home built before 1950. Geographic Information Systems (GIS) were used to map Superfund facilities and develop choropleth maps based on the aforementioned sociodemographic variables. Spatial methods, including mean and median distance analysis, buffer analysis, and spatial approximation were employed to characterize burden disparities. Regression analysis was performed to assess the relationship between the number of Superfund facilities and population characteristics. Spatial coincidence results showed that of the 29.5% of Blacks living in SC, 55.9% live in Superfund host census tracts. Among all populations in SC living below poverty (14.2%), 57.2% were located in Superfund host census tracts. Buffer analyses results (0.5mi, 1.0mi, 5.0mi, 0.5km, 1.0km, and 5.0km) showed a higher percentage of Whites compared to Blacks hosting a Superfund facility. Conversely, a slightly higher percentage of Blacks hosted (30.2%) a Superfund facility than those not hosting (28.8%) while their White counterparts had more equivalent values (66.7% and 67.8%, respectively). Regression analyses in the reduced model (Adj. R2 = 0.038) only explained a small percentage of the variance. In addition, the mean distance for percent of Blacks in the 90th percentile for Superfund facilities was 0.48mi. Burden disparities exist in the distribution of Superfund facilities in SC at the block and census tract levels across varying levels of demographic composition for race/ethnicity and SES.

Jet Injection of 1% buffered lidocaine versus topical ELA-Max for anesthesia before peripheral intravenous catheterization in children: a randomized controlled trial.

PubMed

Spanos, Stephanie; Booth, Rebekah; Koenig, Heidi; Sikes, Kendra; Gracely, Edward; Kim, In K

2008-08-01

Peripheral intravenous (PIV) catheter insertion is a frequent, painful procedure that is often performed with little or no anesthesia. Current approaches that minimize pain for PIV catheter insertion have several limitations: significant delay for onset of anesthesia, inadequate anesthesia, infectious disease exposure risk from needlestick injuries, and patients' needle phobia. Comparison of the anesthetic effectiveness of J-Tip needle-free jet injection of 1% buffered lidocaine to the anesthetic effectiveness of topical 4% ELA-Max for PIV catheter insertion. A prospective, block-randomized, controlled trial comparing J-Tip jet injection of 1% buffered lidocaine to a 30-minute application of 4% ELA-Max for topical anesthesia in children 8 to 15 years old presenting to a tertiary care pediatric emergency department for PIV catheter insertion. All subjects recorded self-reported visual analog scale (VAS) scores for pain at time of enrollment and pain felt following PIV catheter insertion. Jet injection subjects also recorded pain of jet injection. Subjects were videotaped during jet injection and PIV catheter insertion. Videotapes were reviewed by a single blinded reviewer for observer-reported VAS pain scores for jet injection and PIV catheter insertion. Of the 70 children enrolled, 35 were randomized to the J-Tip jet injection group and 35 to the ELA-Max group. Patient-recorded enrollment VAS scores for pain were similar between groups (P = 0.74). Patient-recorded VAS scores were significantly different between groups immediately after PIV catheter insertion (17.3 for J-Tip jet injection vs 44.6 for ELA-Max, P < 0.001). Blinded reviewer assessed VAS scores for pain after PIV catheter insertion demonstrated a similar trend, but the comparison was not statistically significant (21.7 for J-Tip jet injection vs 31.9 ELA-Max, P = 0.23). J-Tip jet injection of 1% buffered lidocaine provided greater anesthesia than a 30-minute application of ELA-Max according to patient self-assessment of pain for children aged 8 to 15 years undergoing PIV catheter insertion.

A Prospective Randomized Trial of Prognostic Genicular Nerve Blocks to Determine the Predictive Value for the Outcome of Cooled Radiofrequency Ablation for Chronic Knee Pain Due to Osteoarthritis.

PubMed

McCormick, Zachary L; Reddy, Rajiv; Korn, Marc; Dayanim, David; Syed, Raafay H; Bhave, Meghan; Zhukalin, Mikhail; Choxi, Sarah; Ebrahimi, Ali; Kendall, Mark C; McCarthy, Robert J; Khan, Dost; Nagpal, Geeta; Bouffard, Karina; Walega, David R

2017-12-28

Genicular nerve radiofrequency ablation is an effective treatment for patients with chronic pain due to knee osteoarthritis; however, little is known about factors that predict procedure success. The current study evaluated the utility of genicular nerve blocks to predict the outcome of genicular nerve cooled radiofrequency ablation (cRFA) in patients with osteoarthritis. This randomized comparative trial included patients with chronic knee pain due to osteoarthritis. Participants were randomized to receive a genicular nerve block or no block prior to cRFA. Patients receiving a prognostic block that demonstrated ≥50% pain relief for six hours received cRFA. The primary outcome was the proportion of participants with ≥50% reduction in knee pain at six months. Twenty-nine participants (36 knees) had cRFA following a prognostic block, and 25 patients (35 knees) had cRFA without a block. Seventeen participants (58.6%) in the prognostic block group and 16 (64.0%) in the no block group had ≥50% pain relief at six months (P = 0.34). A 15-point decrease in the Western Ontario and McMaster Universities Osteoarthritis Index at six months was present in 17 of 29 (55.2%) in the prognostic block group and 15 of 25 (60%) in the no block group (P = 0.36). This study demonstrated clinically meaningful improvements in pain and physical function up to six months following cRFA. A prognostic genicular nerve block using a local anesthetic volume of 1 mL at each injection site and a threshold of ≥ 50% pain relief for subsequent cRFA eligibility did not improve the rate of treatment success. © 2017 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Bayesian nonparametric regression with varying residual density

PubMed Central

Pati, Debdeep; Dunson, David B.

2013-01-01

We consider the problem of robust Bayesian inference on the mean regression function allowing the residual density to change flexibly with predictors. The proposed class of models is based on a Gaussian process prior for the mean regression function and mixtures of Gaussians for the collection of residual densities indexed by predictors. Initially considering the homoscedastic case, we propose priors for the residual density based on probit stick-breaking (PSB) scale mixtures and symmetrized PSB (sPSB) location-scale mixtures. Both priors restrict the residual density to be symmetric about zero, with the sPSB prior more flexible in allowing multimodal densities. We provide sufficient conditions to ensure strong posterior consistency in estimating the regression function under the sPSB prior, generalizing existing theory focused on parametric residual distributions. The PSB and sPSB priors are generalized to allow residual densities to change nonparametrically with predictors through incorporating Gaussian processes in the stick-breaking components. This leads to a robust Bayesian regression procedure that automatically down-weights outliers and influential observations in a locally-adaptive manner. Posterior computation relies on an efficient data augmentation exact block Gibbs sampler. The methods are illustrated using simulated and real data applications. PMID:24465053

Effects of prior aversive experience upon retrograde amnesia induced by hypothermia.

PubMed

Jensen, R A; Riccio, D C; Gehres, L

1975-08-01

Two experiments examined the extent to which retrograde amnesia (RA) is attenuated by prior learning experiences. In Experiment 1, rats initially received either passive avoidance training in a step-through apparatus, exposure to the apparatus, or noncontingent footshock. When training on a second but different passive avoidance task was followed by hypothermia treatment, RA was obtained only in the latter two groups. In Experiment 2, one-way active avoidance training, yoked noncontingent shocks, or apparatus exposure constituted the initial experience. Subsequent step-down passive avoidance training and amnestic treatment resulted in memory loss for the prior apparatus exposure group, but not for either of the preshocked conditions. These experiments demonstrate that certain types of prior aversive experience can substantially modify the magnitude of RA, and, in conjunction with other familiarization studies, emphasize a paradox for interpretations of RA based solely upon CNS disruption. The possibility that hypothermia treatment serves as an important contextual or encoding cue necessary for memory retrieval was considered. It was suggested that prior experience may block RA by enabling rats to differentiate training and treatment conditions.

Development and Evaluation of a Blocking Enzyme-Linked Immunosorbent Assay and Virus Neutralization Assay To Detect Antibodies to Viral Hemorrhagic Septicemia Virus

PubMed Central

Wilson, Anna; Goldberg, Tony; Marcquenski, Susan; Olson, Wendy; Goetz, Frederick; Hershberger, Paul; Hart, Lucas

2014-01-01

Viral hemorrhagic septicemia virus (VHSV) is a target of surveillance by many state and federal agencies in the United States. Currently, the detection of VHSV relies on virus isolation, which is lethal to fish and indicates only the current infection status. A serological method is required to ascertain prior exposure. Here, we report two serologic tests for VHSV that are nonlethal, rapid, and species independent, a virus neutralization (VN) assay and a blocking enzyme-linked immunosorbent assay (ELISA). The results show that the VN assay had a specificity of 100% and sensitivity of 42.9%; the anti-nucleocapsid-blocking ELISA detected nonneutralizing VHSV antibodies at a specificity of 88.2% and a sensitivity of 96.4%. The VN assay and ELISA are valuable tools for assessing exposure to VHSV. PMID:24429071

Charged triblock copolymer self-assembly into charged micelles

NASA Astrophysics Data System (ADS)

Chen, Yingchao; Zhang, Ke; Zhu, Jiahua; Wooley, Karen; Pochan, Darrin; Department of Material Science; Engineering University of Delaware Team; Department of Chemistry Texas A&M University Collaboration

2011-03-01

Micelles were formed through the self-assembly of amphiphlic block copolymer poly(acrylic acid)-block-poly(methyl acrylate)-block-polystyrene (PAA-PMA-PS). ~Importantly, the polymer is complexed with diamine molecules in pure THF solution prior to water titration solvent processing-a critical aspect in the control of final micelle geometry. The addition of diamine triggers acid-base complexation ~between the carboxylic acid PAA side chains and amines. ~Remarkably uniform spheres were found to form close-packed patterns when forced into dried films and thin, solvated films when an excess of amine was used in the polymer assembly process. Surface properties and structural features of these hexagonal-packed spherical micelles with charged corona have been explored by various characterization methods including Transmission Electron Microscopy (TEM), cryogenic TEM, z-potential analysis and Dynamic Light Scattering. The forming mechanism for this pattern and morphology changes against external stimulate such as salt will be discussed.

Evidence that the adenosine A3 receptor may mediate the protection afforded by preconditioning in the isolated rabbit heart.

PubMed

Liu, G S; Richards, S C; Olsson, R A; Mullane, K; Walsh, R S; Downey, J M

1994-07-01

Agonists selective for the A1 adenosine receptor mimic the protective effect of ischaemic preconditioning against infarction in the rabbit heart. Unselective adenosine antagonists block this protection but, paradoxically, the A1 adenosine receptor selective antagonist 8-cyclopentyl- 1,3-dipropylxanthine (DPCPX) does not. The aim of this study was to test the hypothesis that the newly described A3 adenosine receptor, which has an agonist profile similar to the A1 receptor but is insensitive to DPCPX, might mediate preconditioning. Isolated rabbit hearts perfused with Krebs buffer experienced 30 min of regional ischaemia followed by 120 min of reperfusion. Infarct size was measured by tetrazolium staining. In control hearts infarction was 32.2(SEM 1.5)% of the risk zone. Preconditioning by 5 min ischaemia and 10 min reperfusion reduced infarct size to 8.8(2.3)%. Replacing the regional ischaemia with 5 min perfusion with 10 microM adenosine or 65 nM N6-[2-(4-aminophenyl)ethyl]adenosine (APNEA), an adenosine A3 receptor agonist, was equally protective. The unselective antagonist 8-p-sulphophenyl theophylline at 100 microM abolished protection by preconditioning, adenosine, and APNEA, but 200 nM DPCPX did not block protection by any of the interventions. Likewise the potent but unselective A3 receptor antagonist 8-(4-carboxyethenylphenyl)-1,3-dipropylxanthine (BW A1433) completely blocked protection from ischaemic preconditioning. Because protection against infarction afforded by ischaemic preconditioning, adenosine, or the A3 receptor agonist APNEA could not be blocked by DPCPX and because the potent A3 receptor antagonist BW A1433 blocked protection from ischaemic preconditioning, these data indicate that the protection of preconditioning is not exclusively mediated by the adenosine A1 receptor in rabbit heart and could involve the A3 receptor.

Comparison Between Three Different Types of Routing Algorithms of Network on Chip

NASA Astrophysics Data System (ADS)

Soni, Neetu; Deshmukh, Khemraj

Network on Chip (NoC) is an on-chip communication technology in which a large number of processing elements and storage blocks are integrated on a single chip. Due to scalability, adaptive nature, well resource utilization NoCs have become popular in and has efficiently replaced SoCs. NoCs performance depends mainly on the type of routing algorithm chosen. In this paper three different types of routing algorithms are being compared firstly one is deterministic routing (XY routing algorithm), secondly three partially adaptive routing (West-first, North-last and Negative-first) and two adaptive routing (DyAD, OE) are being compared with respect to Packet Injection Rate (PIR) of load for random traffic pattern for 4 × 4 mesh topology. All these comparison and simulation is done in NOXIM 2.3.1 simulator which is a cycle accurate systemC based simulator. The distribution of packets is Poisson type with Buffer depth (number of buffers) of input channel FIFO is 8. Packet size is taken as 8 bytes. The simulation time is taken 50,000 cycles. We found that XY routing is better when the PIR is low. The partially adaptive routing is good when the PIR is moderate. DyAD routing is suited when the load i.e. PIR is high.

Applied Technology on Influence of Humic Substances on Fertilizer, Water-use Efficiency and Soil Health

NASA Astrophysics Data System (ADS)

Seyedbagheri, Mir

2017-04-01

In continuation of over 35 years of on-farm studies on soil organic matter from different humates (functional carbon) and compost, I have documented quantitative improvements in soil health and water-use efficiency. The ability of soil organic matter to bind water has become an important theme for research in past years. Research trials were established to evaluate the efficacy of different commercial functional carbon products derived from Leonardite (highly oxidized lignite) in crop production. In each of these trials, functional carbon (Humic and Fulvic acids) products were used in a randomized complete block design. The use of humic substances creates strong organo-mineral complexes (aggregation), chelation, as well as enhanced buffering capacities. We evaluated data from 3 fields and compared the results. Our observation and field demonstrations indicated there was a marked increase in water retention. Data from humic acid (HA) trials showed that different cropping systems responded differently to different products in relation to yield and quality. The functional carbon products used in the study seemed to enhance fertilizer and water-use efficiency by increasing complexation, chelation and buffering. The consistent use of good quality functional carbons in our replicated plots resulted in a yield increase from 6% to 30% over several decades.

Characterization of charged polymer self-assemblies by multidetector thermal field-flow fractionation in aqueous mobile phases.

PubMed

Greyling, Guilaume; Pasch, Harald

2018-01-12

Charged block copolymer self-assemblies, such as charged micelles, have attracted much attention as versatile drug delivery systems due to their readily tunable characteristics such as size and surface charge. However, current column-based analytical techniques are not suitable to fractionate and comprehensively characterize charged micelles in terms of size, molar mass, chemical composition and morphology. Multidetector thermal field-flow fractionation (ThFFF) is shown to be a unique characterization platform that can be used to characterize charged micelles in terms of size, molar mass, chemical composition and morphology in aqueous mobile phases with various ionic strengths and pH. This is demonstrated by the characterization of poly(methacrylic acid)-b-poly(methyl methacrylate) self-assemblies in high pH buffers as well as the characterization of cationic poly(2-vinyl pyridine)-b-polystyrene and poly(4-vinyl pyridine)-b-polystyrene self-assemblies in low pH buffers. Moreover, it is shown that ThFFF is capable of separating charged micelles according to the corona composition. These investigations prove convincingly that ThFFF is broadly applicable to the comprehensive characterization of amphiphilic self-assemblies even when aqueous mobile phases are used. Copyright © 2017 Elsevier B.V. All rights reserved.

Oxidation and Assimilation of Carbohydrates by Micrococcus sodonensis1

PubMed Central

Perry, Jerome J.; Evans, James B.

1966-01-01

Perry, Jerome J. (North Carolina State University, Raleigh), and James B. Evans. Oxidation and assimilation of carbohydrates by Micrococcus sodonensis. J. Bacteriol. 91:33–38. 1966.—Micrococcus sodonensis is a biotin-requiring strict aerobe that cannot utilize carbohydrates as sole sources of carbon and energy. However, addition of mannose, glucose, sucrose, or maltose to a medium on which the organism can grow resulted in an increase in total growth. M. sodonensis oxidized these sugars without induction, thus indicating the presence of constitutive enzymes for their transport, activation, and metabolism. Under appropriate nonproliferating cell conditions, glucose was readily incorporated into essential constituents of the cell. When glucose-1-C14 and glucose-6-C14 were oxidized by nonproliferating cells, the label was found in both the protein and nucleic acid fractions of the cell. The respiratory quotients of cells oxidizing glucose in saline and in phosphate buffer indicated assimilation of sugar carbon in buffer and virtually no assimilation in saline. The ability of M. sodonensis to completely oxidize glucose and to grow on intermediates of glucose oxidation but not on glucose suggests that glucose may suppress or repress some reaction(s) necessary for growth, and that growth substrates either derepress or circumvent this block. PMID:5903100

Distinct Adsorption Configurations and Self-Assembly Characteristics of Fibrinogen on Chemically Uniform and Alternating Surfaces including Block Copolymer Nanodomains

PubMed Central

2015-01-01

Understanding protein–surface interactions is crucial to solid-state biomedical applications whose functionality is directly correlated with the precise control of the adsorption configuration, surface packing, loading density, and bioactivity of protein molecules. Because of the small dimensions and highly amphiphilic nature of proteins, investigation of protein adsorption performed on nanoscale topology can shed light on subprotein-level interaction preferences. In this study, we examine the adsorption and assembly behavior of a highly elongated protein, fibrinogen, on both chemically uniform (as-is and buffered HF-treated SiO2/Si, and homopolymers of polystyrene and poly(methyl methacrylate)) and varying (polystyrene-block-poly(methyl methacrylate)) surfaces. By focusing on high-resolution imaging of individual protein molecules whose configurations are influenced by protein–surface rather than protein–protein interactions, fibrinogen conformations characteristic to each surface are identified and statistically analyzed for structural similarities/differences in key protein domains. By exploiting block copolymer nanodomains whose repeat distance is commensurate with the length of the individual protein, we determine that fibrinogen exhibits a more neutral tendency for interaction with both polystyrene and poly(methyl methacrylate) blocks relative to the case of common globular proteins. Factors affecting fibrinogen–polymer interactions are discussed in terms of hydrophobic and electrostatic interactions. In addition, assembly and packing attributes of fibrinogen are determined at different loading conditions. Primary orientations of fibrinogen and its rearrangements with respect to the underlying diblock nanodomains associated with different surface coverage are explained by pertinent protein interaction mechanisms. On the basis of two-dimensional stacking behavior, a protein assembly model is proposed for the formation of an extended fibrinogen network on the diblock copolymer. PMID:24708538

Effectiveness of plant-derived proanthocyanidins on demineralization on enamel and dentin under artificial cariogenic challenge

PubMed Central

da SILVA, Ana Paula Pereira; GONÇALVES, Rafael Simões; BORGES, Ana Flávia Sanches; BEDRAN-RUSSO, Ana Karina; SHINOHARA, Mirela Sanae

2015-01-01

Dental caries is considered a disease of high prevalence and a constant problem in public health. Proanthocyanidins (PAs) are substances that have been the target of recent studies aiming to control or treat caries. Objective The aim of this in vitro study was to evaluate the efficacy of a treatment with grape seed extract, under cariogenic challenge, to minimize or even prevent the onset of caries in the enamel and dentin. Material and Methods Blocks of enamel and dentin (6.0x6.0 mm) were obtained from bovine central incisors, polished, and selected by analysis of surface microhardness (SH). The blocks were randomly divided into 3 groups (n=15), according to the following treatments: GC (control), GSE (grape seed extract), GF (fluoride – 1,000 ppm). The blocks were subjected to 6 daily pH cycles for 8 days. Within the daily cycling, the specimens were stored in buffered solution. The blocks were then analyzed for perpendicular and surface hardness and polarized light microscopy. Results The means were subjected to statistical analysis using the ANOVA and Fisher’s PLSD tests (p<0.05). For enamel SH, GF showed the highest hardness values. In the dentin, GF was also the one that showed higher hardness values, followed by GSE. Regarding the cross-sectional hardness values, all groups behaved similarly in both the enamel and dentin. The samples that were treated with GSE and fluoride (GF) showed statistically higher values than the control. Conclusion Based on the data obtained in this in vitro study, it is suggested that grape seed extract inhibits demineralization of artificial carious lesions in both the enamel and dentin, but in a different scale in each structure and in a smaller scale when compared to fluoride. PMID:26221925

The pH-dependent local anesthetic activity of diethylaminoethanol, a procaine metabolite.

PubMed

Butterworth, J F; Lief, P A; Strichartz, G R

1988-04-01

To test whether the products of procaine hydrolysis have local anesthetic actions resembling those of procaine, the authors compared the ability of procaine and its metabolites diethylaminoethanol (DEAE) and para-aminobenzoic acid (PABA) to block compound action potentials in excised, desheathed frog and rat sciatic nerves. Studies were performed in solutions of impermeant buffers at pH 7.4 (corresponding to mammalian physiologic pH) and at pH 9.2 (close to the pKa of procaine and DEAE) to test for extracellular pH-dependent increases in drug permeation and potency. Both procaine and DEAE inhibited compound action potentials at pH 7.4 and 9.2 in a reversible and dose-dependent manner, and both were approximately ten-fold more potent at pH 9.2 than at pH 7.4, procaine inhibiting the action potential height by 50% at 0.15 mM (pH 9.2) and 1.1 mM (pH 7.4), DEAE at 4 mM (pH 9.2) and 70 mM (pH 7.4). In contrast, PABA at concentrations up to 25 mM and at either pH failed to inhibit compound action potentials, and did not modify the effects of DEAE when both drugs were given together. Procaine produced greater use-dependent block at the higher pH and at higher stimulation rates (100 Hz vs. 40 Hz); DEAE produced almost no use-dependent block. These observations suggest: 1) that DEAE might account for some of the neuropharmacologic activity of procaine in techniques that favor the accumulation of metabolites (such as those requiring large doses or prolonged infusions); and 2) that alkalinization of procaine and DEAE solutions appears to increase their potency for both resting and use-dependent block of action potentials.

The role of Na-Ca exchange current in the cardiac action potential.

PubMed

Janvier, N C; Boyett, M R

1996-07-01

Since 1981, when Mullins published his provocative book proposing that the Na-Ca exchanger is electrogenic, it has been shown, first by computer simulation by Noble and later by experiment by various investigators, that inward iNaCa triggered by the Ca2+ transient is responsible for the low plateau of the atrial action potential and contributes to the high plateau of the ventricular action potential. Reduction or complete block of inward iNaCa by buffering intracellular Ca2+ with EGTA or BAPTA, by blocking SR Ca2+ release or by substituting extracellular Na+ with Li+ can result in a shortening of the action potential. The effect of block of outward iNaCa or complete block of both inward and outward iNaCa on the action potential has not been investigated experimentally, because of the lack of a suitable blocker, and remains a goal for the future. An increase in the intracellular Na+ concentration (after the application of cardiac glycoside or an increase in heart rate) or an increase in extracellular Ca2+ are believed to lead to an outward shift in iNaCa at plateau potentials and a shortening of the action potential. Changes in the Ca2+ transient are expected to result in changes in inward iNaCa and thus the action potential. This may explain the shortening of the premature action potential as well as the prolongation of the action potential when a muscle is allowed to shorten during the action potential. Inward iNaCa may play an important role in both normal and abnormal pacemaker activity in the heart.

Histomorphometric analysis following augmentation of the anterior atrophic maxilla with cancellous bone block allograft.

PubMed

Nissan, Joseph; Marilena, Vered; Gross, Ora; Mardinger, Ofer; Chaushu, Gavriel

2012-01-01

Grafting with bone blocks may be required to restore the alveolar process in extremely atrophic maxillae prior to implant placement to ensure both function and esthetics. The present study was conducted to histologically and histomorphometrically evaluate the application of allograft cancellous bone blocks for the augmentation of the anterior atrophic maxilla. Consecutive patients with severe atrophy in the anterior maxilla underwent augmentation with cancellous bone block allografts. Bony deficiencies of at least 3 mm horizontally and up to 3 mm vertically according to computed tomographic para-axial reconstructions served as inclusion criteria. After 6 months, implants were placed and a cylindric sample core from the graft area was collected. All specimens were prepared for histologic and histomorphometric examination. Forty patients were included in the study. Eighty-three implants were placed in bone that was augmented with 60 cancellous freeze-dried bone block allografts. The implant survival rate was 98.8%. Mean follow-up was 48 ± 22 months (range, 14 to 82 months). The mean percentage of newly formed bone was 33% ± 18%, that of the residual cancellous block allograft was 26% ± 17%, and marrow and connective tissue comprised 41% ± 2%. Statistically significant histomorphometric differences regarding newly formed bone and residual cancellous block allograft were found between younger (< 40 years) and older (≥ 40 years) patients, respectively. Age did not appear to influence the percentage of marrow and connective tissue. Cancellous bone block allograft is biocompatible and osteoconductive, permitting new bone formation following augmentation of extremely atrophic anterior maxillae in a two-stage implant placement procedure. New bone formation was age-dependent.

Volunteering predicts health among those who value others: two national studies.

PubMed

Poulin, Michael J

2014-02-01

The purpose of these studies was to examine the role of positive views of other people in predicting stress-buffering effects of volunteering on mortality and psychological distress. In Study 1, stressful life events, volunteering, and hostile cynicism assessed in a baseline Detroit-area survey (N = 846) predicted survival over a 5-year period, adjusting for relevant covariates. In Study 2, stressful life events, volunteering, and world benevolence beliefs assessed in a baseline national survey (N = 1,157) predicted psychological distress over a 1-year period, adjusting for distress at baseline. In Study 1, a Cox proportional hazard model indicated that for individuals low in cynicism, stress predicted mortality at low levels of volunteering but not at high levels of volunteering. This effect was not present among those high in cynicism. In Study 2, multiple regression analysis revealed that among individuals high in world benevolence beliefs, stress predicted elevated distress at low levels of volunteering but not at high levels of volunteering. This effect was absent for those lower in world benevolence beliefs. Consistent with prior research on helping behavior, these studies indicate that helping behavior can buffer the effects of stress on health. However, the results of these studies indicate that stress-buffering effects of volunteering are limited to individuals with positive views of other people. Not all individuals may benefit from volunteering, and health-promotion efforts seeking to draw on health benefits of helping behavior may need to target their approach accordingly. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Family conflict and academic performance of first-year Asian American undergraduates.

PubMed

Bahrassa, Nazneen F; Syed, Moin; Su, Jenny; Lee, Richard M

2011-10-01

This three-study investigation examined risk and protective factors for poor academic performance among Asian American first-year undergraduates. Students were surveyed prior to starting college and their GPA was collected after their first semester in college. Family conflict as a significant risk factor for poor academic performance was examined in all three studies. The results indicate that higher family conflict prior to college was related to lower first-semester college GPA, after controlling for standardized test scores and high school rank (Studies 1-3). Even though psychological distress was related to both family conflict and GPA, it did not mediate the relationship between family conflict and GPA (Studies 2 and 3). In terms of protective factors, the results indicate that life satisfaction buffered the negative effects of family conflict on first-semester college GPA (Study 3). Together, these findings support the need to take into account family variables and psychological well-being in the academic performance of Asian American students as they transition from high school to college.

Preventive maintenance system for the photomultiplier detector blocks of PET scanners

DOEpatents

Levy, A.V.; Warner, D.

1995-01-24

A system including a method and apparatus for preventive maintenance of PET scanner photomultiplier detector blocks is disclosed. The qualitative comparisons used in the method of the present invention to provide an indication in the form of a display or printout advising the user that the photomultiplier block is stable, intermittently unstable, or drifting unstable, and also advising of the expected date of failure of a photomultiplier block in the PET scanner. The system alerts the user to replace the defective photomultiplier block prior to catastrophic failure in a scheduled preventative maintenance program, thus eliminating expensive and unscheduled downtime of the PET scanner due to photomultiplier failure. The apparatus for carrying out the method of the present invention preferably resides in the host computer controlling a PET scanner. It includes a memory adapted for storing a record of a number of iterative adjustments that are necessary to calibrate the gain of a photomultiplier detector block i at a time t[sub 0], a time t[sub 1] and a time T, where T>t[sub 1]>t[sub 0], which is designated as Histo(i,j(t)). The apparatus also includes a processor configured by a software program or a combination of programmed RAM and ROM devices to perform a number of calculations and operations on these values, and also includes a counter for analyzing each photomultiplier detector block i=1 through I of a PET scanner. 40 figures.

Preventive maintenance system for the photomultiplier detector blocks of pet scanners

DOEpatents

Levy, Alejandro V.; Warner, Donald

1995-01-24

A system including a method and apparatus for preventive maintenance of PET scanner photomultiplier detector blocks is disclosed. The quantitive comparisons used in the method of the present invention to provide an indication in the form of a display or printout advising the user that the photomultiplier block is stable, intermittently unstable, or drifting unstable, and also advising of the expected date of failure of a photomultiplier block in the PET scanner. The system alerts the user to replace the defective photomultiplier block prior to catastrophic failure in a scheduled preventative maintenance program, thus eliminating expensive and unscheduled downtime of the PET scanner due to photomultiplier failure. The apparatus for carrying out the method of the present invention preferably resides in the host computer controlling a PET scanner. It includes a memory adapted for storing a record of a number of iterative adjustments that are necessary to calibrate the gain of a photomultiplier detector block i at a time t.sub.0, a time t.sub.1 and a time T, where T>t.sub.1 >t.sub.0, which is designated as Histo(i,j(t)). The apparatus also includes a processor configured by a software program or a combination of programmed RAM and ROM devices to perform a number of calculations and operations on these values, and also includes a counter for analyzing each photomultiplier detector block i=1 through I of a PET scanner.