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51.
Stitzer Maxine L.; Petry Nancy; Peirce Jessica; Kirby Kimberly; Killeen Therese; Roll John; Hamilton John; Stabile Patricia Q.; Sterling Robert; Brown Chanda; Kolodner Ken; Li Rui 《Canadian Metallurgical Quarterly》2007,75(5):805
Intake urinalysis test result (drug positive vs. negative) has been previously identified as a strong predictor of drug abuse treatment outcome, but there is little information about how this prognostic factor may interact with the type of treatment delivered. The authors used data from a multisite study of abstinence incentives for stimulant abusers enrolled in outpatient counseling treatment (N. M. Petry, J. M. Peirce, et al., 2005) to examine this question. The first study urine was used to stratify participants into stimulant negative (n = 306) versus positive (n = 108) subgroups. Abstinence incentives significantly improved retention in those testing negative but not in those testing positive. Findings suggest that stimulant abusers presenting to treatment with a stimulant-negative urine benefit from abstinence incentives, but alternative treatment approaches are needed for those who test stimulant positive at intake. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
Kinetics of vapor phase oxidation of o-xylene has been studied over sintered and compacted vanadium pentoxide in a continuous stirred tank catalytic reactor in the temperature range of 450–517°C at atmospheric pressure. The major product obtained is phthalic anhydride. The other products are maleic anhydride and carbon dioxide. The reaction rate data are well represented (with average absolute deviation less than 6%) by the following expression derived by applying the steady-state oxidation-reduction model of Mars and van Krevelen to a parallel reaction scheme and assuming first order with respect to both o-xylene and oxygen: Significantly, the activation energies for all three postulated reactions with rate constants k1, k2, and k3 turn out to be identical having a value of 14.8 kcal/mole, which may be taken to imply that there is only one rate-influencing reaction step for all the products and not three as assumed in deriving this equation. 相似文献
53.
Airborne viable, non-viable, and allergenic fungi in a rural agricultural area of India: a 2-year study at five outdoor sampling stations 总被引:1,自引:0,他引:1
Adhikari A Sen MM Gupta-Bhattacharya S Chanda S 《The Science of the total environment》2004,326(1-3):123-141
The information on airborne allergenic fungal flora in rural agricultural areas is largely lacking. Adequate information is not available to the bioaerosol researchers regarding the choice of single versus multiple sampling stations for the monitoring of both viable and non-viable airborne fungi. There is no long-term study estimating the ratios of viable and non-viable fungi in the air and earlier studies did not focus on the fractions of airborne allergenic fungi with respect to the total airborne fungal load. To fill these knowledge gaps, volumetric paired assessments of airborne viable and non-viable fungi were performed in five outdoor sampling stations during two consecutive years in a rural agricultural area of India. Samples were collected at 10-day intervals by the Burkard Personal Slide Sampler and the Andersen Two-Stage Viable Sampler. The data on the concentrations of total and individual fungal types from five stations and 2 different years were analyzed and compared by statistical methods. The allergenicity of the prevalent airborne viable fungi was estimated by the skin-prick tests of >100 rural allergy patients using the antigenic fungal extracts from isolates collected with the Andersen sampler. The ranges of total fungal spore concentration were 82-2365 spores per cubic meter of air (spores/m3) in the first sampling year and 156-2022 spores/m3 in the second sampling year. The concentration ranges of viable fungi were 72-1796 colony-forming units per cubic meter of air (CFU/m3) in the first sampling year and 155-1256 CFU/m3 in the second sampling year. No statistically significant difference was observed between the total spore data of the 2 years, however, the data between five stations showed a significant difference (P<0.0001). No statistically significant difference existed between stations and years with respect to the concentration of viable fungi. When the data of individual allergenic fungal concentrations were compared between stations and years, no statistically significant difference was observed in all cases except for Aspergillus japonicus and Rhizopus nigricans, which showed significant difference in case of stations and years, respectively. The ratios between the total fungal spores collected by the Burkard sampler and the viable fungi collected by the Andersen sampler from all sampling stations ranged between 0.29 and 7.61. The antigenic extracts of eight prevalent viable airborne fungi (A. flavus, A. japonicus, A. fumigatus, Alternaria alternata, Cladosporium cladosporioides, Curvularia pallescens, Fusarium roseum, and R. nigricans) demonstrated >60% positive reactions in the skin prick test. These selected allergenic fungi collectively represented 31.7-63.2% of the total airborne viable fungi in different stations. The study concluded that: (i) a rich fungal airspora existed in the rural study area, (ii) to achieve representative information on the total airborne fungal spores of an area, the monitoring in multiple sampling stations is preferable over a single sampling station; for viable fungi, however, one station can be considered, (iii) the percentage of airborne fungal viability is higher in rural agricultural areas, and (iv) approximately 52% of the viable airborne fungi in the rural study area were allergenic. 相似文献
54.
A combination of room-temperature photoluminescence (PL) mapping, low-temperature PL spectroscopy, and resistivity mapping
was applied to establish the origin of resistivity variations in different types of semi-insulating (SI) 6H-SiC substrates.
Direct correlation between the native-defect PL and resistivity was found in undoped (V-free) SI samples. The regions with
high PL intensity also showed high resistivity, indicating that native point defects are associated with the compensation
mechanism in those substrates and its nonhomogeneity. A more complex correlation was established for the vanadium-doped samples.
In these samples, V-related PL and native point defect-related PL were both present at room temperature. While there was no
clear correlation between the resistivity maps and the maps of PL intensity measured at either of the two peaks separately,
the resistivity was in good correlation with the total PL signal consisting of both vanadium and intrinsic defect contributions.
The resistivity of those wafers was apparently due to the contribution of both V-related and native point defect-related deep
levels. 相似文献
55.
Deeptendu Bikash Dhar Bhabatosh Chanda 《International Journal on Document Analysis and Recognition》2006,8(4):232-245
With the emergence of Geographical Information Systems (GIS), map acquisition and recognition have become hotly pursued topics, both by the industry and the academia. The paper presents a novel methodology for the extraction and recognition of symbol features from topographic maps. The method proceeds by separating the map into its constituent layers and then attempting to recognize the features in different layers on the basis of symbol-specific geometrical and morphological attributes. Text strings have also been separated. The output is obtained in the form of an ‘e-map’ that is vectorized and hence is suitable for GIS. To demonstrate the usefulness of the proposed system a simple database along with a query processing facility is constructed integrating the information obtained from the e-map and ‘some’ user inputs. The methodology has been observed to perform quite satisfactorily. 相似文献
56.
S. Mandal S. P. Chowdhury A. K. Das Bhabatosh Chanda 《International Journal on Document Analysis and Recognition》2006,8(2-3):172-182
The requirement of detection and identification of tables from document images is crucial to any document image analysis and digital library system. In this paper we report a very simple but extremely powerful approach to detect tables present in document pages. The algorithm relies on the observation that the tables have distinct columns which implies that gaps between the fields are substantially larger than the gaps between the words in text lines. This deceptively simple observation has led to the design of a simple but powerful table detection system with low computation cost. Moreover, mathematical foundation of the approach is also established including formation of a regular expression for ease of implementation. 相似文献
57.
H. Sushmitha Jagannath Chanda Amitabha Saha Prasenjit Ghosh Rabindra Mukhopadhyay 《应用聚合物科学杂志》2021,138(20):50419
In a pneumatic tire, the contained air carries the load of the vehicle and also augments performance for other functional requirements, such as, rolling resistance, ride and handling, durability, and so on. The inner liner of the tire is responsible to ensure air retention by virtue of its high air impermeability. The present study focused on developing inner-liner compounds of improved air impermeability by utilizing platelet filler (layered silicate). The obtained organoclay was subjected to a pre-treatment process called exfoliation to increase the d spacing between the clay layers that further improved the morphological aspect of the compound. The inner-liner compound has been modified by partial replacement of carbon black with organically modified bentonite clay in 1:1 and 2.5:1 ratio. Air impermeability of rubber compounds was tested in a gas permeability tester. Field emission scanning electron microscope, transmission electron microscope, atomic force microscope, and x-ray diffraction were utilized to understand the distribution and dispersion of clay in the rubber compounds. Fatigue crack growth analysis was carried out to measure the fatigue life of the materials. The modified compounds exhibited air impermeability improvement from 7% to 30% vs the reference carbon-black filled compound with improved mechanical properties and filler dispersion. 相似文献
58.
Measurement of the mixed state thermoelectric power of pure and vanadium substituted 2223 pellets of the type (Bi0.6Pb0.2–y
V
y
)2Sr2Ca2Cu3O
x
are presented for temperatures between 77 and 120 K. Mixed state Seebeck voltages for both pure and vanadium substituted samples show almost similar features. Our data forT>0.8T
c
could be explained, attributing the observed dissipation to the normal quasiparticle excitations. For temperatures below 0.8T
c
, we argue that the dominant contribution to the mixed state Seebeck voltage may originate from the dissipation induced by the fluctuations of the order parameter across the internal weak links. 相似文献
59.
60.
In response to several women who presented with postpartum depression in 1 year, a group of nurses developed a task force made up of hospital nurses, obstetricians, psychiatrists, pediatricians, family practitioners, lactation specialists, home care nurses, and mental health counselors. The purposes of this task force were to educate health care professionals about postpartum depression, to help identify women who might be affected, and to develop interventions for adjusting to parenthood. This article details the evolution of that task force, and how it has assisted not only the women but also the health care providers involved. 相似文献