Assessing the Elastic Moduli of Pavement Marking Tapes using the Tape Drape Test

Temporary pavement marking (TPM) tape adhesion with roadway surfaces is critical for tape performance. The two main TPM performance issues both stem from the adhesive strength. Weak adhesion results in premature detachment and excessive adhesion requires extensive removal processes that often leave ghost markings, both of which can cause dangerous confusion in road construction zones. Tape adhesion is directly related to the elastic modulus [Formula: see text] of TPM tapes. Thus, accurate characterization of [Formula: see text] before tape installation is essential to fully understand and predict the adhesion performance and ultimately the durability of TPMs. To determine the most appropriate [Formula: see text] characterization technique for three different commercial TPM tape brands, two commonly used techniques—tensile and three-point bend testing—were compared with a less common technique, the Peirce cantilever testing or “Tape Drape Test” (ASTM D1388-18). The Tape Drape Test was the only method that accurately characterized [Formula: see text] of tapes with raised surface features. Measured [Formula: see text] values from tensile and three-point bend testing showed significant variation caused by the structural features of the tapes. The Tape Drape Test, which can be implemented quickly in the field before tape installation with little equipment, effectively characterized [Formula: see text] for all the tapes to inform tape adhesion performances and installation procedures.

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Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074768 ◽

1983 ◽

Vol 41 ◽

pp. 194-195

Author(s):

D. F. Blake ◽

L. F. Allard ◽

D. R. Peacor

Keyword(s):

High Resolution ◽

Marine Invertebrates ◽

Sea Urchins ◽

Structural Features ◽

Sea Stars ◽

High Resolution Tem ◽

Relationship Of ◽

The Relationship ◽

Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

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Ultrastructural identification of three types of sensory setae on copepod antennae

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100141159 ◽

1995 ◽

Vol 53 ◽

pp. 956-957

Author(s):

T. M. Weatherby ◽

P.H. Lenz

Keyword(s):

Phase Locking ◽

Membrane Surface ◽

Reaction Times ◽

High Sensitivity ◽

Structural Features ◽

Calanoid Copepods ◽

Marine Food Webs ◽

Dendritic Membrane ◽

Ultrastructural Characterization

Crustaceans, as well as other arthropods, are covered with sensory setae and hairs, including mechanoand chemosensory sensillae with a ciliary origin. Calanoid copepods are small planktonic crustaceans forming a major link in marine food webs. In conjunction with behavioral and physiological studies of the antennae of calanoids, we undertook the ultrastructural characterization of sensory setae on the antennae of Pleuromamma xiphias.Distal mechanoreceptive setae exhibit exceptional behavioral and physiological performance characteristics: high sensitivity (<10 nm displacements), fast reaction times (<1 msec latency) and phase locking to high frequencies (1-2 kHz). Unusual structural features of the mechanoreceptors are likely to be related to their physiological sensitivity. These features include a large number (up to 3000) of microtubules in each sensory cell dendrite, arising from or anchored to electron dense rods associated with the ciliary basal body microtubule doublets. The microtubules are arranged in a regular array, with bridges between and within rows. These bundles of microtubules extend far into each mechanoreceptive seta and terminate in a staggered fashion along the dendritic membrane, contacting a large membrane surface area and providing a large potential site of mechanotransduction.

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Quantitative nano-characterization of heterogeneous catalysts

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138361 ◽

1995 ◽

Vol 53 ◽

pp. 398-399

Author(s):

P.A. Crozier ◽

M. Pan

Keyword(s):

Heterogeneous Catalysts ◽

Low Dose ◽

Imaging Techniques ◽

Structural Features ◽

Catalyst Characterization ◽

New Developments ◽

Double Phase ◽

Phase Systems ◽

Dose Imaging

Heterogeneous catalysts can be of varying complexity ranging from single or double phase systems to complicated mixtures of metals and oxides with additives to help promote chemical reactions, extend the life of the catalysts, prevent poisoning etc. Although catalysis occurs on the surface of most systems, detailed descriptions of the microstructure and chemistry of catalysts can be helpful for developing an understanding of the mechanism by which a catalyst facilitates a reaction. Recent years have seen continued development and improvement of various TEM, STEM and AEM techniques for yielding information on the structure and chemistry of catalysts on the nanometer scale. Here we review some quantitative approaches to catalyst characterization that have resulted from new developments in instrumentation.HREM has been used to examine structural features of catalysts often by employing profile imaging techniques to study atomic details on the surface. Digital recording techniques employing slow-scan CCD cameras have facilitated the use of low-dose imaging in zeolite structure analysis and electron crystallography. Fig. la shows a low-dose image from SSZ-33 zeolite revealing the presence of a stacking fault.

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kangaroo, a Mobile Element From Volvox carteri, Is a Member of a Newly Recognized Third Class of Retrotransposons

Genetics ◽

10.1093/genetics/162.4.1617 ◽

2002 ◽

Vol 162 (4) ◽

pp. 1617-1630

Author(s):

Leonard Duncan ◽

Kristine Bouckaert ◽

Fay Yeh ◽

David L Kirk

Keyword(s):

Genomic Structure ◽

Mobile Element ◽

Direct Repeat ◽

Structural Features ◽

Volvox Carteri ◽

Developmentally Regulated ◽

Closed Circle ◽

Integration Mechanisms ◽

And Function

Abstract Retrotransposons play an important role in the evolution of genomic structure and function. Here we report on the characterization of a novel retrotransposon called kangaroo from the multicellular green alga, Volvox carteri. kangaroo elements are highly mobile and their expression is developmentally regulated. They probably integrate via double-stranded, closed-circle DNA intermediates through the action of an encoded recombinase related to the λ-site-specific integrase. Phylogenetic analysis indicates that kangaroo elements are closely related to other unorthodox retrotransposons including PAT (from a nematode), DIRS-1 (from Dictyostelium), and DrDIRS1 (from zebrafish). PAT and kangaroo both contain split direct repeat (SDR) termini, and here we show that DIRS-1 and DrDIRS1 elements contain terminal features structurally related to SDRs. Thus, these mobile elements appear to define a third class of retrotransposons (the DIRS1 group) that are unified by common structural features, genes, and integration mechanisms, all of which differ from those of LTR and conventional non-LTR retrotransposons.

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Characterization of putative salinity-responsive biomarkers in olive (Olea europaea L.)

Plant Genetic Resources ◽

10.1017/s1479262121000174 ◽

2021 ◽

pp. 1-11

Author(s):

Monther T. Sadder ◽

Ahmad F. Ateyyeh ◽

Hodayfah Alswalmah ◽

Adel M. Zakri ◽

Abdullah A. Alsadon ◽

...

Keyword(s):

Food Production ◽

Stress Protein ◽

Adaptor Protein ◽

Structural Features ◽

Nacl Stress ◽

Soil Salinization ◽

Limiting Factors ◽

Stress Levels ◽

Quality Water

Abstract Low-quality water and soil salinization are increasingly becoming limiting factors for food production, including olive – a major fruit crop in several parts of the world. Identifying putative salinity-stress tolerance in olive would be helpful in the future development of new tolerant varieties. In this study, novel salinity-responsive biomarkers (SRBs) were characterized in the species, namely, monooxygenase 1 (OeMO1), cation calcium exchanger 1 (OeCCX1), salt tolerance protein (OeSTO), proteolipid membrane potential modulator (OePMP3), universal stress protein (OeUSP2), adaptor protein complex 4 medium mu4 subunit (OeAP-4), WRKY1 transcription factor (OeWRKY1) and potassium transporter 2 (OeKT2). Unique structural features were highlighted for encoded proteins as compared with other plant homologues. The expression of olive SRBs was investigated in leaves of young plantlets of two cultivars, ‘Nabali’ (moderately tolerant) and ‘Picual’ (tolerant). At 60 mM NaCl stress level, OeMO1, OeSTO, OePMP3, OeUSP2, OeAP-4 and OeWRKY1 were up-regulated in ‘Nabali’ as compared with ‘Picual’. On the other hand, OeCCX1 and OeKT2 were up-regulated at three stress levels (30, 60 and 90 mM NaCl) in ‘Picual’ as compared to ‘Nabali’. Salinity tolerance in olive presumably engages multiple sets of responsive genes triggered by different stress levels.

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Synthesis and Characterization of a Fullerenol Derivative for Potential Biological Applications

Materials Proceedings ◽

10.3390/iocn2020-07793 ◽

2020 ◽

Vol 4 (1) ◽

pp. 15

Author(s):

Eduardo Ravelo-Nieto ◽

Alvaro Duarte-Ruiz ◽

Luis H. Reyes ◽

Juan C. Cruz

Keyword(s):

Phase Transfer ◽

Protein A ◽

Structural Features ◽

Cellular Level ◽

Cellulose Membrane ◽

Cell Penetration ◽

Covalent Functionalization ◽

Dialysis Tubing ◽

Surface Functionality

Several biological barriers are generally responsible for the limited delivery of cargoes at the cellular level. Fullerenols have unique structural features and possess suitable properties for interaction with the cells. This study aimed to synthesize and characterize a fullerenol derivative with desirable characteristics (size, charge, functionality) to develop cell penetration vehicles. Fullerenol was synthesized from fullerene (C60) solubilized in toluene, followed by hydroxylation with hydrogen peroxide and tetra-n-butylammonium hydroxide (TBAH) as a phase transfer catalyst. The obtained product was purified by a Florisil chromatography column (water as the eluent), followed by dialysis (cellulose membrane dialysis tubing) and freeze-drying (yield 66%). Subsequently, a silane coupling agent was conjugated on the fullerenol surface to render free amine functional groups for further covalent functionalization with other molecules. Characterization via UV–VIS, FTIR-ATR, Raman, DLS, and SEM techniques was conducted to evaluate the composition, size, morphology, surface functionality, and structural properties. We are currently working on the conjugation of the potent cell-penetrating agents Buforin II (BUFII) and the Outer Membrane Protein A (OmpA) on the surface of the fullerenol to estimate whether cell penetration and endosome escape are improved concerning conventional polymeric vehicles and our previous developments with iron oxide nanoparticles.

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High-resolution characterization of the structural features and genetic variation of six feline leukocyte antigen class I loci via single molecule, real-time (SMRT) sequencing

Immunogenetics ◽

10.1007/s00251-021-01221-w ◽

2021 ◽

Author(s):

Jennifer C. Holmes ◽

Elizabeth H. Scholl ◽

Allison N. Dickey ◽

Paul R. Hess

Keyword(s):

Genetic Variation ◽

High Resolution ◽

Real Time ◽

Single Molecule ◽

Structural Features ◽

Class I ◽

Smrt Sequencing ◽

Leukocyte Antigen ◽

Leukocyte Antigen Class I

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Preparation and Characterization of Cationized Cellulose for the Removal of Anionic Dyes

Adsorption Science & Technology ◽

10.1260/0263617011494088 ◽

2001 ◽

Vol 19 (3) ◽

pp. 197-210 ◽

Cited By ~ 32

Author(s):

A. Hashem ◽

Reda M. El-Shishtawy

Keyword(s):

Adsorption Capacity ◽

Freundlich Isotherm ◽

Structural Features ◽

Isotherm Models ◽

Acid Orange 7 ◽

Anionic Dyes ◽

Adsorption Parameters ◽

Direct Blue ◽

Equilibrium Data

The factors influencing the cationization of microcrystalline cellulose with 3-chloro-2-hydroxypropyl triethylammonium chloride in the presence of NaOH were investigated. The course of the reaction was followed by estimating the nitrogen content of the cationized product while its structural features were confirmed by IR analysis. The ability of cationized cellulose to adsorb anionic dyes, viz. Acid Orange 7, Direct Blue 75 and Direct Violet 31, was investigated at 25°C and 50°C. The equilibrium data obtained were fitted by the Langmuir and Freundlich isotherm models, allowing the corresponding adsorption parameters to be determined. The results showed that the adsorption capacity was dependent on the adsorbent, temperature, the nature of the dye and (to some extent) on van der Waals and hydrogen bonding. Cationized cellulose exhibited a much better adsorption capacity towards anionic dyes than cellulose.

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