Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Effects of prior saline-morphine discrimination by pigeons on three-way discrimination including two morphine doses (1989)
    Springer
    Psychopharmacology 98 (1989), S. 222-230 
    Details
    ISSN: 1432-2072
    Keywords: Drug discrimination ; Naltrexone ; Morphine ; Amphetamine ; Antagonism ; Pigeons
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The discriminative stimulus properties of morphine sulfate (MS) and their alteration by naltrexone (NTX) and d-amphetamine (AMP) challenges were examined in a quantitative dose 1, dose 2, and saline (SAL) drug discrimination task utilizing 1.8 mg/kg MS, 10 mg/kg MS, and SAL as discriminative stimuli under a fixed-ratio 30 schedule of food-maintained behavior in two groups of White Carneaux pigeons. Group A (Gp A) (n=6) subjects (Ss) were initially experimentally-and drug-naive, whereas group B Ss (n=4) were originally trained in a two-choice MS versus SAL discrimination task, and had a long behavioral and drug history. Significant differences were found in (1) number of sessions to criterion (STC) (group B greater than group A); (2) group A Ss generalized both NTX and AMP to SAL, whereas group, B Ss generalized AMP to the low dose (1.8 mg/kg) MS stimulus; and (3) in drug interaction test sessions, the high dose MS stimulus (10 mg/kg) in group A was unmodified by a range of challenge AMP doses (0.32 to 3.2 mg/kg). In contrast, group B Ss exhibited a shift to the low dose or SAL-appropriate keys when the same high dose MS stimulus was challenged by moderate doses of AMP. Group A and group B were similar in their pattern and distribution of responses when tested with various doses of MS, and also when challenge tests of the high dose MS stimulus were made with NTX. Qualitative generalization tests with the opiate agonist methadone suggested that methadone was more potent than MS in producing the discriminative stimulus properties learned under the MS stimulus conditions. It is suggested that the three-choice dose 1, dose 2, SAL discrimination procedure is a viable model to test agonist and antagonist relationships.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00444695
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    The discriminative stimulus properties of legal, over-the-counter stimulants administered singly and in binary and ternary combinations (1993)
    Springer
    Psychopharmacology 110 (1993), S. 309-319 
    Details
    ISSN: 1432-2072
    Keywords: OTC stimulants ; Cocaine ; Amphetamine ; Drug discrimination ; Drug mixtures
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Ninety-six male Sprague-Dawley rats were trained in one of seven drug versus saline (SAL) discrimination (DD) tasks under a variable-ratio 5–15 schedule of food-motivated lever press responding. Three groups of rats (n=12/group) were trained to discriminate between one of the legal over-the-counter (OTC) stimulants — caffeine (CAF), ephedrine (EPHED), phenylpropanolamine (PPA), and SAL. Three other groups (n=2/group) were trained to discriminate between one of three binary stimulant combinations — CAF + EPHED, CAF + PPA, EPHED + PPA, and SAL. The seventh group of rats (n=24) was trained to discriminate between SAL and a ternary combination of the OCT stimulants, CAF + EPHED + PPA. Generalization tests were conducted with each of the OTC stimulants and the controlled stimulants — amphetamine (AMPHET) and cocaine (COC). The data suggest: 1) there is cross-generalization between some OTC combinations and controlled stimulants; 2) full generalization between the OTC and controlled stimulants were demonstrated in rats trained to discriminate two of the binary stimulant combinations from SAL; 3) drug mixtures are not perceived as new entities distinct from their component elements; 4) training dose-ratio may influence the characteristics of mixture discriminations; 5) stimulus overshadowing may be a factor determining drug mixture cues, and 6) the DD properties of aggregate drug compounds may function within a euclidean metric space. We propose that some binary OTC stimulant combinations may effectively function as a methadone-like replacement therapy in cocaine dependence.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02251286
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Evidence for perceptual masking of the discriminative morphine stimulus (1989)
    Springer
    Psychopharmacology 98 (1989), S. 212-221 
    Details
    ISSN: 1432-2072
    Keywords: Drug discrimination ; Naltrexone ; Amphetamine ; Masking
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Morphine-amphetamine and morphine-naltrexone interactions were examined in three groups of White Carneaux pigeons (n=3), which were trained in a twochoice drug discrimination procedure under a FR-30 schedule of food reinforcement using 3.2 mg/kg morphine and saline as discriminative stimuli. Once stimulus control was acquired by these initial training stimuli, the training doses of morphine were gradually changed to 1.0 mg/kg for group A and to 10 mg/kg for group C. The three groups differed in the minimum dose required for stimulus control and the drugs to which the training stimulus generalized. Stimulus generalization to amphetamine was inversely related to training dose. Amphetamine potentiated the discriminative stimulus properties of morphine. Naltrexone blocked the discriminative stimulus properties of morphine to varying degrees, which appeared to be limited by the training dose and the rate-suppressing effects of naltrexone when administered alone. Challenging the morphine stimulus with amphetamine resulted in a qualitatively similar blockade. This blockade was a direct function of the morphine training dose. It is argued that MS-AMP interactions result in perceptual masking of the MS stimulus, which can be differentiated from pharmacological antagonism by NTX. Two other challenge drugs, ketamine, and sodium pentobarbital, did not alter stimulus control by morphine.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00444694
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    A model viscoelastic fluid (1978)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 18 (1978), S. 1037-1043 
    Details
    ISSN: 0032-3888
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Shear stress and first normal stress difference data are presented for materials which exhibit a constant viscosity and yet at the same time exhibit elasticity levels of the same order as polymer melts. Flow pattern observations in circular die entry flows in conjunction with independent shear and normal stress measurement strongly suggest that these fluids would make excellent model fluids for melt studies. Studies in which the influence of elasticity in the absence of shear thinning and fluid inertia can easily be made. Furthermore it is clearly shown that a realistic solution to the die entry flow problem is not obtained using second order flow theory. In the second order region the secondary cell is observed to be almost identical in size to the cell observed for an inelastic Newtonian fluid in creeping flow. Marked growth in the secondary cell as a function of elasticity is not observed until the shear rates exceed the region of second order behavior. This growth in cell size as a result of elasticity is followed at higher shear rates by a spiraling flow instability like that observed for some polymer melts.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760181311
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Structure-property relationships in polyamide/acrylonitrile-butadiene-styrene (ABS) blends (1987)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 27 (1987), S. 1582-1590 
    Details
    ISSN: 0032-3888
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The structures and physical properties of four blends of poly(acrylonitrile-co-styrene-g-butadiene) (ABS) materials with polycaprolactam (PA6) have been characterized. The blends were separated into components by selective solvent extraction and were found to contain different structures: Blend A contained no PA6 grafts. Blend B contained PA6 grafted onto both soluble and insoluble ABS. Blend C contained PA6 grafted onto soluble poly(styrene-co-acrylonitrile) (p-SAN). In Blend D, PA6 was grafted onto both the insoluble ABS and the p-SAN phases. Transmission electron microscopy showed different morphologies in the blends. Blend A had a co-continuous, somewhat laminar structure, while Blend D consisted of an ABS phase dispersed in a PA6 continuum. Blends B and C had intermediate structures. All four blends, however, had very similar rheological and physical properties despite the variation in structure.
    Additional Material: 19 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760272104
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Improving clay-based tailings disposal: Case study on coal tailings (1997)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 43 (1997), S. 1894-1903 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The role of swelling clays in hindering the compressional dewatering characteristics of coal-mine tailings is examined. The effects of electrolyte concentration and ion exchange in improving the shear and compressional rheology are compared. Suspensions studies include actual mine tailings (thickener feed and thickener underflow) as well as synthetic clay dispersions made from clay collected from the coal seam. It was shown that the most important parameter in controlling the properties of the tailings suspension is “controlled” dispersion in the presence of a Ca2+ electrolyte concentration in excess of that required to (1) prevent initial swelling and (2) provide full cation exchange of the clay. Under these electrolyte conditions, complete delamination of the clay did not occur, and both the dewatering and handling characteristics of the resultant suspensions improved dramatically.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690430724
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Yield stress of suspensions loaded with size distributed particles (1997)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 43 (1997), S. 1171-1179 
    Details
    ISSN: 0001-1541
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A new theoretical approach is proposed for the yield stress of concentrated, flocculated particulate suspensions. Explicit cognizance is taken for the three-dimensional, mechanically rigid particle network held together by interparticle forces wherein the mean coordination number in the assemblage increases and the separation between the particles decreases with an increase in the volume fraction of the solid phase. The Rump-Molerus model relting isotropic normal stress and isotropic normal interparticle force in a bed of single-sized spheres is modified to incorporate the size distribution of particles and extended to the suspension network. The model estimates the yield stress as a function of solids loading for various kinds of size distribution and is in reasonable agreement with experimental data when the surface properties of the particle are held constant.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aic.690430506
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...