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51.
KB Reddy P Gascard MG Price EV Negrescu JE Fox 《Canadian Metallurgical Quarterly》1998,273(52):35039-35047
Signaling across integrins is regulated by interaction of these receptors with cytoskeletal proteins and signaling molecules. To identify molecules interacting with the cytoplasmic domain of the beta3-integrin subunit (glycoprotein IIIa), a placental cDNA library was screened in the yeast two-hybrid system. Two identical clones coding for a 96-amino acid sequence were identified. This sequence was 100% identical to a sequence in skelemin, a protein identified previously in skeletal muscle. Skelemin is a member of a superfamily of cytoskeletal proteins that contain fibronectin-type III-like motifs and immunoglobulin C2-like motifs and that regulate the organization of myosin filaments in muscle. The amino acid residues in the isolated clones encompassed C2 motifs 4 and 5 of skelemin. A recombinant skelemin protein consisting of C2 motifs 3-7 interacted with beta1- and beta3-integrin cytoplasmic domains expressed as glutathione S-transferase (GST) fusion proteins, but not with GST-beta2-integrin cytoplasmic tail or GST alone. The skelemin-binding region was in the membrane proximal cytoplasmic domains of the integrins. Full-length skelemin interacted with integrin in intact cells as demonstrated by the colocalization of hemagglutinin-tagged skelemin in Chinese hamster ovary (CHO) cells containing alphaIIbbeta3-integrin and by the finding that microinjection of C2 motif 4 of skelemin into C2C12 mouse myoblast cells caused spread cells to round up. A skelemin-like protein was detected in CHO cells, endothelial cells, and platelets, and this protein colocalized with beta1- and beta3-integrins in CHO cells. This study suggests the presence of a skelemin-like protein in non-muscle cells and provides evidence that it may be involved in linking integrins to the cytoskeleton. 相似文献
52.
High-sensitivity titration calorimetry is used to measure changes in enthalpy, heat capacity and protonation for the binding of captopril to the angiotensin I-converting enzyme (ACE; EC 3.4.15.1). The affinity of ACE to captopril is high and changes slightly with the pH, because the number of protons linked to binding is low. The determination of the enthalpy change at different pH values suggests that the protonated group in the captopril-ACE complex exhibits a heat protonation of approximately -30 kJ/mol. This value agrees with the protonation of an imidazole group. The residues which may become protonated in the complex could be two histidines existing in two active sites, which are joined to the amino acids coordinated to Zn2+. Calorimetric measurements indicate that captopril binds to two sites in the monomer of ACE, this binding being enthalpically unfavorable and being dominated by a large positive entropy change. Thus, binding is favored by both electrostatic and hydrophobic interactions. The temperature dependence of the free energy of binding deltaG degrees is weak because of the enthalpy-entropy compensation caused by a large heat capacity change, deltaCp =-4.3+/-0.1 kJ/K/mol of monomeric ACE. The strong favorable binding entropy and the negative deltaCp indicate both a large contribution to binding due to hydrophobic effects, which seem to originate from dehydration of the ligand-protein interface, and slight conformational changes in the vicinity of the active sites. 相似文献
53.
A Nandakumar N Anantha L Appaji K Swamy G Mukherjee T Venugopal S Reddy M Dhar 《Canadian Metallurgical Quarterly》1996,7(4):405-410
While fairly complete and reliable incident data on childhood cancers are available from the registries in India, mortality and survival information is not. Information concerning the latter was obtained by the Bangalore cancer registry through active follow-up involving visits to homes of patients. Between 1982 and 1989, 617 cases of cancers in childhood were registered, giving an age-standardized incidence rate of 84.8 and 48.4 per million in male and female children, respectively. Active follow-up provided mortality/survival information in 532 or 86.2 percent of these cases. Overall, observed five-year survival was 36.8 percent (both genders combined) with a relative survival of 37.5 percent when childhood mortality in the general population was taken into account. The five-year relative survival was best for thyroid carcinoma (100 percent) followed by Hodgkin's disease (73 percent) and retinoblastoma (72.9 percent). Survival was comparatively low, being 9.9 percent in acute nonlymphatic leukemia and less than 20 percent in rhabdomyosarcoma and the category grouped as 'other malignant neoplasms.' Survival in Hodgkin's disease was influenced by clinical stage at presentation, but was not statistically significant possibly due to small numbers. 相似文献
54.
Using time-driven activity-based costing to manage digital forensic readiness in large organisations
A digital forensic readiness (DFR) programme consists of a number of activities that should be chosen and managed with respect to cost constraints and risk. Traditional cost systems, however, can not provide the cost of individual activities. This makes it difficult or impossible for organisations to consider cost when making decisions about specific activities. In this paper we show that the relatively new cost system, time-driven activity-based costing (TDABC), can be used to determine the cost of implementing and managing activities required for DFR. We show through analysis and simulation that the cost information from a TDABC model can be used for such decisions. We also discuss some of the factors that ought to be considered when implementing or managing the use of TDABC in a large organisation. 相似文献
55.
The cooling and average local solidification times were determined for slow solidifiation of Al-4.4 wt% Cu alloy under natural convection and under electromagnetically forced axisymmetric rotation during liquid cooling and solidification in graphite moulds. Cooling rates were measured within situ thermocouples. The conditions needed to stabilize the radial temperature gradient with rotation were established. The microstructure size decreased with increasing rotation, as did the local solidification times. The average grain and dendrite size without imposed rotation is coarser near the mould wall compared with the centre of the casting. This trend is reversed with imposed rotation. Rotation also led to a smaller spread of grain and dendrite size at any chosen height of the casting. These results are discussed in relation to existing theories, and several reasons for an improved heat transfer coefficient with rotation are presented. Forced convective solidification was then carried out for various shapes of integral investment cast Nimonic-90 alloy solidifying under modified conditions that prevented columnar grain formation. Similar results to those recorded for the aluminium case were obtained and are presented here. The major conclusion is that observations indicating a reduction of microstructure spacing during forced convection should also consider improved heat extraction at the mould-metal interface.List of symbols
Gr
Grashof number =gTZ
3
3/
3
-
g
r
acceleration in radial direction
-
g
acceleration in direction
-
g
z
acceleration inZ direction (gravity)
-
h
heat transfer coefficient
-
k
l
thermal conductivity of liquid
-
Nu
z
Nusselt number =hZ/k
l
-
Pr
Prandtl number =/
-
Ra
Rayleigh numberGr Pr
-
R
radius of mould
-
Re
r
Reynolds number =V
0
R/
-
T
temperature
- T
temperature difference in radial direction
-
Ta
Taylor number =
24H
4
W
2/
2
-
V
velocity
-
W
r.p.m.
-
thermal diffusivity
-
coefficient of volume expansion
-
viscosity
-
density
Mr G. S. Reddy is also a post graduate student registered at the Banaras Hindu University, Varanasi, India. 相似文献
56.
Silicon - In modern days, one or the way, development of infrastructure plays a major role that decides upon the matrix of our lifestyle. The development of geopolymer concrete (GPC) is an... 相似文献
57.
Silicon - In this paper, a dielectric modulated dual material gate TFET (DM-DMG_TFET)based biosensor is proposed. In order to detect various biomolecules, a nanogap cavity is formed by the... 相似文献
58.
Arivazhagan L. Nirmal D. Reddy P. Pavan Kumar Ajayan J. Godfrey D. Prajoon P. Ray Ashok 《SILICON》2021,13(9):3039-3046
Silicon - In this paper, AlGaN/GaN High Electron Mobility Transistor (HEMT) with stacked passivation (Diamond/SiN) is proposed and investigated. The implementation of stacked passivation in HEMT... 相似文献
59.
The photopolymerization of styrene with a well‐defined molecular architecture and a low polydispersity index and with methyl and phenylseleno (? SePh) groups at α‐ and ω‐chain ends, respectively, was performed via a controlled/living radical polymerization with a new initiating system, 1‐(phenylseleno)ethyl benzene/tert‐butyl diphenyl (phenylseleno) silane, through the absorption of visible light at room temperature. A novel initiating living radical polymerization was examined. The yield and number‐average molecular weight (Mn) of the resulting polymer increased with the reaction time. Furthermore, a linear relationship was found in a plot of Mn versus the polymer yield. These results indicated that this polymerization proceeded through a living radical mechanism. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 348–355, 2004 相似文献
60.
Tracer tests were conducted at the 6,000 pounds of ozone per day Tucson, CAP Water Treatment Plant in Tucson, Arizona. The tests were designed to determine T10 values through the contactors at various operating conditions. The tests were modeled using three techniques. Peclet Number was calculated for each of the runs, which would indicate the hydrodynamic conditions inside the ozone contactor. The results indicated that the increase in water flow rate and the number of cells with gas flow increased Peclet Number. The flow rate of liquid seemed to impact the Peclet Number more than gas flow. The headloss in each cell appeared to be important in controlling the distribution of liquid and gas through the cell. A correlation was developed between the product of gas and liquid phase Reynolds Number and Peclet Number. 相似文献