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21.
Digant Gupta Christopher G Lis Sadie L Dahlk Jessica King Pankaj G Vashi James F Grutsch Carolyn A Lammersfeld 《Nutrition journal》2008,7(1):19
Background
Bioelectrical Impedance (BIA) derived phase angle is increasingly being used as an objective indicator of nutritional status in advanced cancer. Subjective Global Assessment (SGA) is a subjective method of nutritional status. The objective of this study was to investigate the association between BIA derived phase angle and SGA in advanced colorectal cancer. 相似文献22.
Applying the critical path method to manufacturing routing 总被引:1,自引:0,他引:1
Traditionally the critical path method (CPM) has been used primarily as an a'priori planning and scheduling device. Its applications have typically been limited to one-shot projects, usually with a long period of completion time. This paper proposes taking these ideas to continuous production systems, and to implement the CPM not just at the outset but throughout the process. The algorithm calls for repeatedly calculating the critical path through the production process and routing parts so as to remain off this path. Before the model is presented, some basic ideas are introduced from group technology (GT) and CPM. After the presentation of the model, two potential implementations with the usage of computer are proposed. 相似文献
23.
Lussier Isabelle; Derevensky Jeffrey L.; Gupta Rina; Bergevin Tanya; Ellenbogen Stephen 《Canadian Metallurgical Quarterly》2007,21(2):165
The study of resilient children has overturned many deficit-focused models concerning the ontogenesis of children raised in adversity. This study explored the relationship between risk and protective factors, resilience, and youth gambling behavior. More specifically, this study examined the relative contribution of various risk and protective domains in relation to problem gambling behavior and examined whether youth identified as resilient (high risk exposure- high internalized protection) were as likely as those identified as vulnerable (high risk exposure-low internalized protection) to engage in excessive gambling behavior. The sample consisted of 1,273 students ages 12 to 19. The findings demonstrated that risk and protective factors each provide a unique contribution to the prediction model of gambling problems. Resilient and vulnerable youth differed significantly in their self-reported gambling severity. As well, resilient youth were not statistically distinguishable from low-risk exposure groups in terms of their gambling severity. Findings are interpreted with respect to resilience and prevention research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
24.
Sudhir Singh Bhadauria Dr. Mahesh Chandra Gupta 《Canadian Metallurgical Quarterly》2007,21(3):234-239
Reports of failure of existing concrete structures due to a lack of durability, rather than a deficiency in structural strength, has made concrete technologists, engineers, and researchers focus research on the parameters influencing durability performance with respect to time. Systematic performance monitoring, with respect to chosen durability parameters of existing concrete structures, will decide the direction of future research in this area. Inferences based on laboratory simulations and testing need to be confirmed by in situ field measurements and studies. In situ condition rating and performance monitoring surveys have been conducted by many researchers, scientists, and professional associations, and reported in literature. Inferences of few such studies are summarized and discussed. Deterioration of concrete structures constructed in recent times is observed at relatively faster rates, and has been mainly attributed to cracking. Cracking is associated with the use of faster-hydrating portland cements with increased fineness and the tricalcium silicate (C3S) content to support the high speed of modern construction. In the present research, a case study of deteriorated water tank structures situated in the semitropical region of India is presented. Some selected parameters—such as concrete cover, carbonation depth, chloride concentration, compressive strength, etc. which influence long term durability of structures—have been measured. 相似文献
25.
In this study, an aluminum based metallic matrix (Al-2wt.% Cu) was reinforced with SiC particulates using a conventional casting technique and a new disintegrated melt deposition technique. Microstructural characterization studies conducted on the samples taken from disintegrated melt deposition technique revealed a more uniform distribution of SiC particulates and good interfacial integrity between SiC particulates and metallic matrix when compared to the conventionally cast composite samples. Results of ambient temperature mechanical tests demonstrate an increase in 0.2% YS and ultimate tensile strength of samples taken from disintegrated melt deposition technique when compared with the unreinforced and conventionally cast composite samples. The results of microstructural characterization and mechanical testing were finally rationalized in terms of the nature of processing technique employed to reinforce Al-2wt.% Cu metallic matrix with SiC particulates. 相似文献
26.
J. M. Ballingall P. Ho J. Mazurowski L. Lester K. C. Hwang J. Sutliff S. Gupta J. Whitaker 《Journal of Electronic Materials》1993,22(12):1471-1475
InxGa1−xAs (x=0.25–0.35) grown at low temperature on GaAs by molecular beam epitaxy is characterized by Hall effect, transmission
electron microscopy, and ultrafast optical testing. As with low temperature (LT) GaAs, the resistivity is generally higher
after a brief anneal at 600°C. High-resolution transmission electron microscopy shows all the as-grown epilayers to be heavily
dislocated due to the large lattice mismatch (2–3%). When the layers are annealed, in addition to the dislocations, precipitates
are also generally observed. As with LT-GaAs, the lifetime shortens as growth temperature is reduced through the range 300–120°C;
also, the lifetime in LT-InxGa1−xAs is generally shorter in as-grown samples relative to annealed samples. Metal-semiconductor-metal photodetectors fabricated
on the material exhibit response times of 1–2 picoseconds, comparable to results reported on GaAs grown at low temperature,
and the fastest ever reported in the wavelength range of 1.0–1.3 μm. 相似文献
27.
Ionic conductivity in poly(vinyl butyral) based polymeric electrolytes: Effect of solvents and salts
Li+ conductive solid polymeric electrolytes (SPEs) have been prepared by complexing Li salts LiX (X = I, SCN, CLO4, CF3SO3) with poly(vinyl butyral) (PVB) an amorphous polymer with a low Tg value and well known for its outstanding laminating properties. These self-supporting SPEs have been prepared by the solution cast technique using cyclohexanone, tetrahydrofuran, and n-butyl alcohol as solvents. The XRD and DSC investigations correlated to measured ionic conductivities have revealed that in addition to the amorphous nature of the resulting complex, its Tg value, the concentration and the values of the lattice energies of the complexing salts, the solvent used in making the SPEs also govern the value of ionic conductivity. Highest ionic conductivity values attained in SPEs made with n-butyl alcohol are explained in terms of the interception of the hydrogen bonding due to solvation. 相似文献
28.
Poly(ethylene aspartate) [PEA] was synthesized by the melt condensation of D,L-aspartic acid and ethylene glycol. PEA containing pendent amino and carbonyl groups in its repeating chain was used as the polymeric ligand for complexation with transition metal ions, viz. Co(II), Ni(II), Cu(II), Mn(II), Zn(II), Cd(II), Ca(II), Mg(II), Pb(II) and Hg(II). Complexation was found to be most effective in DMSO. The resulting polyester-metal complexes were solid coloured materials which have been characterized by IR spectroscopy, elemental analysis and magnetic susceptibility measurements. The thermal stability of the polyester-metal complexes was investigated by thermogravimetric analysis (TGA). On the basis of the physico-chemical studies, an oxygen and nitrogen coordinated structure for the polyester-metal complexes is proposed. 相似文献
29.
Ciby Thomas S. Haldar Manoj Khanna S. Rajesh K.K. Gupta R.S. Gupta 《Microelectronics Reliability》1998,38(12):1955-1961
Analytical model for the transconductance, cut off frequency, transit time and fringing capacitance of LDD MOSFETs is presented with a simple approach. The analysis is carried out considering the LDD device as a conventional MOSFET with a series resistance [Z.-H. Liu et al., Threshold voltage model for submicrometer MOSFETs. IEEE Trans Electron Devices 1993; ED-40: 86–94] and a simple closed form expressions for cut off frequency and transit time is obtained. The total gate capacitance, i.e. the geometric and fringing capacitance, is calculated for both LDD and non-LDD devices and lower fringing capacitance is reported in LDD devices. Lower cut-off frequencies and higher transit time are reported in LDD devices for the same channel length. 相似文献
30.
Quantitation of Cefaclor in Pharmaceutical Dosage Forms Using High Performance Liquid Chromatography
Mary Mathew V. Das Gupta Charlie Bethea 《Drug development and industrial pharmacy》1993,19(14):1723-1729
A stability-indicating high-performance liquid chromatography for the quantitation of cefaclor in pharmaceutical dosage forms has been developed. The method is accurate and precise with a percent relative standard deviation of 1.2 based on 5 readings. A number of inactive ingredients present in the capsules and suspensions did not interfere with the assay procedure. The extraction procedure from the dosage forms is very simple. The recovery from the synthetic mixtures was quantitative. The capsules which had expired 3 years ago lost only 3% of the potency. The drug appears to be very sensitive to strong acids or bases since a 5 minute boiling caused 100% degradation of drug in both the solutions. 相似文献