A single pulse of 1.5
kJ, from a 300
μF capacitor, was applied to 0.7
g of atomized spherical Ti powders to produce a porous-surfaced implant compact by environmental electro-discharge sintering ...(EEDS) in a low vacuum atmosphere. A solid core was formed by a discharge in the middle of the compact which is surrounded by a porous layer. Ti, C and O were the main constituents, with a smaller amount of N. The EEDS implant surface was lightly oxidized and was primarily in the form of TiO
2. The lightly etched sample showed the surface form of metallic Ti, indicating that the EEDS breaks down the oxide film of the as-received Ti powder during the discharge process. However, a small amount of N in the form of nitride, which was also found in the as-received Ti powder, was not changed in its chemical state by EEDS.
In the conventional carbon nanotube backlight units (CNT-BLUs), light passes through the phosphor-coated anode glass plate, which thus faces closely the thin film transistor (TFT) backplate of a ...liquid crystal display panel. This configuration makes heat dissipation structurally difficult because light emission and heat generation occur simultaneously at the anode. We propose a novel configuration of a CNT-BLU where the cathode rather than the anode faces the TFT backplate by turning it upside down. In this design, light passes through the transparent cathode glass plate while heating occurs at the anode. We demonstrated a novel design of CNT-BLU by fabricating transparent single-walled CNT field emitters on the cathode and by coating a reflecting metal layer on the anode. This study hopefully provides a clue to solve the anode-heating problem which would be inevitably confronted for high-luminance and large-area CNT-BLUs.
A charge transport mechanism in double oxide-nitride dielectric was studied experimentally and theoretically. We have found that widely accepted Frenkel effect or thermally assisted tunneling could ...not explain experimental current-field-temperature dependences. For the first time we demonstrate that ionization mechanism of deep traps, which control charge transport in silicon nitride, is due to multiphonon process.
In a wide variety of cell types, including neurons and smooth muscle cells, activation of the large-conductance voltage- and Ca²⁺-activated K⁺ (BK) channels causes transient membrane ...hyperpolarization, thereby regulating cellular excitability. Similar to other voltage-gated ion channels, BK channels, a tetramer of α-subunits, associate with auxiliary β-subunits in a tissue-specific manner, modifying the channel's gating properties. The BK β1-subunit, which is expressed in smooth muscle, increases the apparent Ca²⁺ sensitivity (marked by a hyperpolarizing shift in the conductance-voltage relationship at a given Ca²⁺ concentration), slows macroscopic activation and deactivation, and is required for channel activation by 17β-estradiol. The β1-subunit is essential for normal regulation of vascular smooth muscle contractility and blood pressure. Little is known, however, about the molecular mechanisms of β1-subunit modulation of α-subunits. Here we show that the β1-subunit's modulation of the Ca²⁺ and 17β-estradiol sensitivities can be dissociated from its effects on gating kinetics by truncation of the α-subunit's extracellular N-terminal residues. The BK α-subunit N terminus interacts uniquely with the β1-subunit: β2 regulation of the α-subunit is unaltered by truncation of the N terminus. Although the functional interaction of α and β1 requires the N-terminal tail of α, the physical association requires the S1, S2, and S3 transmembrane helices of α.
A single pulse of 0.75–2.0
kJ/0.7
g atomized spherical Ti–6Al–4V powder using 150, 300 and 450
μF capacitors was applied in an Ar atmosphere. After discharge, the self-assembled solid core surrounded ...by a porous layer was composed of Widmanstätten α
+
β grains. By manipulating the discharge conditions such as input energy and capacitance, including powder size, porous-surfaced Ti–6Al–4V implant-typed compacts with various porosities can be produced in short times less than 200
μs without changing the unique microstructure.
The present investigation was undertaken to determine the adsorption characteristics of nano-scaled porous carbons using a gravimetric adsorption technique through CCl
4 and NH
3 adsorption studies ...in the two different relative pressure ranges. Nano-scaled pore volumes (
W
0) determined from CCl
4 adsorption isotherms were generally in good agreement with the BET surface area. However, the adsorption capacity of NH
3 in the very low relative pressure range was independent of the surface area of the carbon samples. This can be attributed to the presence of a greater number of active adsorption sites related to higher density of surface oxygen and surface oxygen functional groups on the lower surface area carbons. The degree of surface area development and nano-scaled pore volume control the adsorption process in the high relative pressure range, and the surface chemistry affects the adsorption process in the very low relative pressure range.
A single pulse from a 300muF capacitor was applied to spherical Ti-6Al-4V powders in an N2 atmosphere. Consolidation of powders occurred by a discharge, resulting in a microporous compact with pores ...from 30 to 100mum in diameter. The surface has been simultaneously modified into the form of TiOxNy from TiO2. The input energy influence on the formation of a solid core and surface chemistry of the compact was investigated.
Juvenile hormone (JH) and ecdysone are the key hormones controlling insect growth and development. The juvenile hormone binding protein (JHBP) is the first member in the array of proteins ...participating in JH signal transmission. In the present report a whole jhbp gene sequence (9790 bp) is described. The jhbp gene contains four introns (A–D). All the introns have common flanking sequences: GT at the 5′ and AG at the 3′ end. The first intron is in phase 1, the second in phase 2, and the third and fourth in phase 1. An analysis of these sequences suggests that U2-class spliceosomes are involved in intron excision from pre-mRNA. Several horizontally transmitted elements from other genes were found in the introns. All jhbp exons are positioned in local AT-reach regions of the gene. A search for core promoter regulatory elements revealed that the TATA box starts 29 bp preceding the start of transcription; the sequence TCAGTA representing a putative initiator sequence (Inr) starts at position +14. Eight characteristic sequences for binding Broad-Complex gene products, which coordinate the ecdysone temporal response, are present in the non-coding sequence of the jhbp gene. An analysis of exon locations and intron phases indicates that jhbp gene organization is related to the retinol binding protein gene, a member of the lipocalin family.
The epidermal growth factor receptor (EGFR) is overexpressed and/or constitutively activated in a variety of human malignancies. Detection of increased expression levels of EGFR in cancer and the ...association between overexpression and decreased patient survival has led to the development of several therapeutic strategies to target this receptor. The results of early-phase clinical trials to date suggest that targeting EGFR alone may not be sufficient to eradicate established tumors. This limited antitumor efficacy as monotherapy has led to combining EGFR inhibitors with chemotherapy or radiation therapy for advanced disease, or incorporating EGFR inhibition to cancer prevention approaches. This review will discuss the role of EGFR signaling in carcinogenesis and the rationale for EGFR inhibition as a clinical prevention and treatment strategy.
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