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71.
Research in the 1980s uncovered ubiquitous neuropeptide-receptor distribution in brain structures associated with emotional processing, and throughout many organ systems. This finding supported neuropeptides as biochemical substrates of emotion, and the neuropeptide-receptor network as a parasynaptic system crossing traditional brain-body boundaries. The medical relevance of these findings was affirmed by psychoneuroimmunology research: neuropeptides help to regulate immunocyte trafficking, there is bidirectional communication between nervous and immune system components, immunocytes produce neuropeptides, and nerve cells produce immune-associated cytokines. In the past decade, the concept of a unified psychosomatic network has been strengthened by animal and human research demonstrating relationships between behavior and neuropeptide-mediated regulation of immune functions. Research on emotional expression or disclosure in healthy human subjects as well as in cancer and HIV-positive patients has shown significant positive correlations with clinically relevant immune functions and/or positive health outcomes. Psychosocial interventions emphasizing emotional expression or active coping have evidenced survival benefits in breast cancer and melanoma. These findings suggest that emotional expression generates balance in the neuropeptide-receptor network and a functional healing system. Emotional expression is also a marker for psychospiritual vitalization, and further research should evaluate links between energy-based models of health and neuropeptide-receptor-based models under the rubric of an informational paradigm. 相似文献
72.
V Chandrasekaran Ch Sreerama Murthy P Subrahmaniam G Venkateswarlu 《Bulletin of Materials Science》1986,8(1):39-48
Iron-chromium-cobalt alloys possess attractive magnetic properties combined with good formability and hence are identified as technologically important magnetic materials. Alloys with compositions Fe-28·9 Cr-15·6 Co and Fe-28·4 Cr-20·1Co (weight percent) have been studied. Heat-treatment parameters during thermomagnetic treatment viz temperature, time and external magnetic field were optimized with reference to magnetic properties. The fully treated anisotropic alloys develop remanence=11·5–12·0 kilo Gauss, coercivity=600–650 Oersted and energy product=4–4·5 million Gauss Oersted. Electron microscopic and Mössbauer spectroscopic techniques were used to identify the original and transformed phases. During the various stages of the development of the alloy, the changes in mechanical hardness were correlated with magnetic hardness. 相似文献
73.
Diels-alder adducts from safflower oil fatty acids: I. Maleic anhydride as dienophile 总被引:1,自引:0,他引:1
G. S. R. Sastry B. G. K. Murthy J. S. Aggarwal 《Journal of the American Oil Chemists' Society》1971,48(11):686-688
The Diels-Alder reaction between alkali conjugated and elaidinized safflower oil fatty acids and maleic anhydride was studied
under various experimental conditions. The principal product which was obtained in 51–55% yields was a mixture of the adduct
of maleic anhydride and maleic acid in 40∶60 proportions. The isolation and properties of this mixed adducts from the reaction
mixture and their conversion to trimethyl, tributyl and triallyl esters are described. The trimethyl ester was also obtained
in good yield from the methyl esters of the fatty acids and dimethyl maleate. 相似文献
74.
G. S. R. Sastry B. G. K. Murthy J. S. Aggarwal 《Journal of the American Oil Chemists' Society》1972,49(3):192-195
The Diels-Alder adducts from alkali conjugated and elaidinized safflower fatty acids with acrylic, methacrylic, crotonic and
cinnamic acids and their esters as dienophiles were obtained in 40–64% yields. Low yields of 16–18% were obtained when 10-undecenoic
acid and its ester were used. Most of the adducts could be estimated quantitatively in the reaction products by column chromatography
or gas liquid chromatography (GLC). For the estimation of the adducts from crotonic and 10-undecenoic acids a combination
of column chromatography and GLC techniques was employed. Partitioning between hexane and 90% methanol, partial esterification
with alkali washing, and splitting and fractional distillation under reduced pressure were methods used to obtain the adducts
in 90–95% purity. 相似文献
75.
Dhiraj Murthy Alexander Gross Alexander Pensavalle 《Journal of Computer-Mediated Communication》2016,21(1):33-49
This article explores intersections between place, race/ethnicity, and gender amongst American Twitter users and makes an argument that studying the intensity of tweets provides insights into how and why particular groups tweet. Given recent events in American political life such as the shooting in Ferguson, Missouri and the reactions by young, urban African Americans on Twitter, understanding the role of race, place, gender, and age is important. We observed the time between tweets of urban American Twitter users and explored whether the medium may be providing traditionally marginalized groups, such as young Black men, with potential avenues for mobilizing communication and access to resources. 相似文献
76.
Metal-ceramic composites produced via directed melt oxidation (DIMOX) of aluminium alloys are of recent interest. Thein situ composite forming method is based on the reaction of a molten alloy with a gaseous oxidant. In the present study, Al-Mg-Si alloys were subjected to directed melt oxidation and the progressive microstructural evolution was examined by interrupted growth experiments. In the early stages, liquid alloy oxidizes to form a duplex oxide layer (MgO+MgAl2O4) on the surface. The openings in these oxide layers allow the liquid alloy to wick through to form small nodules on the surface. When further wicking occurs through these nodules, a cauliflower type of colonies is formed. During the early part of the second stage, spinel growth dominates to form a multi-layered structure. In the final stage, as the magnesium reaches low levels, Al2O3 formation dominates the growth, and alumina crystals grow continuously for several tens of micrometres. The oxygen required for alumina formation is expected to come from two sources: (i) from the ingress of oxygen through microcracked oxide layers, and (ii) demixing of magnesium-containing oxides in the underneath layers. 相似文献
77.
Coiled bodies (CBs) are nuclear organelles whose structures appear to be highly conserved in evolution. In rapidly cycling cells, they are typically located in the nucleoplasm but are often found in contact with the nucleolus. The CBs in human cells contain a unique protein, called p80-coilin. Studies on amphibian oocyte nuclei have revealed a protein within the "sphere" organelle that shares significant structural similarity to p80-coilin. Spheres and CBs are also highly enriched in small nuclear ribonucleoproteins and other RNA-processing components. We present evidence that, like spheres, CBs contain U7 small nuclear RNA (snRNA) and associate with specific chromosomal loci. Using biotinylated 2'-O-methyl oligonucleotides complementary to the 5' end of U7 snRNA and fluorescence in situ hybridization, we show that U7 is distributed throughout the nucleoplasm, excluding nucleoli, and is concentrated in CBs. Interestingly, we found that CBs often associate with subsets of the histone, U1, and U2 snRNA gene loci in interphase HeLa-ATCC and HEp-2 monolayer cells. However, in a strain of suspension-grown HeLa cells, called HeLa-JS1000, we found a much lower rate of association between CBs and snRNA genes. Possible roles for CBs in the metabolism of these various histone and snRNAs are discussed. 相似文献
78.
This article analyzes the transmission line characteristics of plasmonic hybrid metal insulator metal (HMIM) waveguide, circular ring resonator (CRR) based dual-band band-pass filters with two transmission poles in both pass-bands in the optical regime using coupled line feed. The transmission line characteristics of an HMIM waveguide, such as characteristic impedance (ZPV), effective refractive index (neff) and propagation length (Lspp), have been obtained by using full wave simulation. Using basic HMIM slot waveguide, a CRR with periodic loading of double- and triple-ring CRR is numerically analyzed. Two input ports have been used for excitation, which are located at the separation of 180° positions along the CRR, and are coupled with the ring by parallel coupled lines, producing the dual pass-bands with the synchronous excitation of two transmission poles. The proposed double-ring dual-band band-pass filter (DR-DB-BPF) offers 35 dB extinction ratio (ER), 299.69 nm free spectral range (FSR) and narrow band full width half maximum (FWHM) of 78.057—112.43 nm. The triple-ring DB-BPF (TR-DB-BPF) has 22.5 dB ER, FSR of 292.18 nm and FWHM of 42.751—59.58 nm. The proposed filters are very useful in the development of dual-band filters for electronic photonic integrated circuits (EPICs), as the optical signals are filtered at two wavelengths simultaneously. 相似文献
79.
S. Shanmuga Priya D. Yuvaraj T. Satyanarayana Murthy Varghese S. Chooralil S. Navaneetha Krishnan P. Banumathy P. SundaraVadivel 《计算机系统科学与工程》2022,43(3):887-896
Authentication is important to the security of user data in a mobile cloud environment. Because of the server’s user credentials, it is subject to attacks. To maintain data authentication, a novel authentication mechanism is proposed. It consists of three independent phases: Registration, login, and authentication and key agreement. The user registers with the Registration Center (RC) by producing a secret number that isn’t stored in the phone, which protects against privileged insider attacks. The user and server generate a nonce for dynamic user identity and agree on a session secret key for safe communication. The passwords are not stored on the computer or provided in plain text, they are resistant to replay, guessing, and stolen verification attacks. The suggested protocol uses a one-way hash function and XOR operations, with the client having remote access to a large number of servers over a secure communication channel. Concentrates on HMAC and SHA3 for Collision Free Hashing and to overcome length extension attacks. HMACs are substantially less affected by collisions than their underlying hashing algorithms alone. So adding an HMAC to an MD5 or SHA hash would make it substantially more difficult to break via a rainbow table. 相似文献
80.
Seong-Hwan Cho Afshin Karshenas Akhtarhusein A. Tayebali Murthy N. Guddati 《International Journal of Pavement Engineering》2017,18(12):1098-1110
The debonding distress in asphalt pavement structures is a critical problem that affects the performance of asphalt concrete pavements. It occurs at the layer interface due to the poor bond quality between adjacent asphalt concrete layers and/or when stresses at the layer interface exceed the strengths of the material at the interface. The debonding of the adjacent layers, especially the top surface layer of an asphalt pavement, is a contributing factor to the premature cracking of pavements. Hence, the debonding distress can lead to a reduction in the life of the pavement. This paper presents an analytical and experimental framework to evaluate the potential for debonding at the layer interface of asphalt concrete pavements. Computational analysis was performed to determine the critical stress and strain states in layered asphalt pavements under moving vehicle loads using the Layered ViscoElastic pavement analysis for Critical Distresses (LVECD) computer program developed at North Carolina State University. This computational analysis enables a greater understanding of the critical stress that is involved in debonding and the ways that such stress is affected by pavement design parameters and environmental conditions. In addition, a prediction model was developed that can determine the shear bond strength at the interface of asphalt concrete layers with different tack coat materials at various temperatures, loading rates and normal confining stresses. The systematic and mechanistic framework developed in this study employs the maximum shear ratio concept as a shear failure criterion and provides a tool to evaluate the effects of various loading, environmental and pavement factors on the debonding potential of asphalt pavements. The overall advantages of the mechanistic framework and approach using the LVECD analysis tool will help lead to better understanding of the debonding mechanism, proper selection of the tack coats, and economic benefit in highway pavement maintenance and rehabilitation costs. 相似文献