Fluorescence-based zinc ion sensor for zinc ion release from pancreatic cells

In this paper, we describe the synthesis and characterization of analytical properties of fluorescence-based zinc ion-sensing glass slides and their application in monitoring zinc ion release from beta pancreatic cells in cell cultures. To fabricate the sensors, the zinc ion indicator ZnAF-2 {6-[N-[N',N'-bis(2-pyridinylmethyl)-2-aminoethyl]amino-3',6'-dihydroxyspiro[isobenzofuran-1(3H),9'-[9H]xanthene]-3-one} was modified to include a sufficiently long linking aliphatic chain with a terminal carboxyl functional group. The recently synthesized ZnAF-2 zinc ion indicator provided high zinc ion selectivity in physiological solutions containing millimolar levels of calcium and other possible interfering cations. The carboxyl-modified ZnAF-2 was conjugated to the activated surface of glass slides, which then served as zinc ion sensors. It was possible to grow pancreatic cells directly on the zinc-sensing glass slide or on a membrane placed on these glass slides. The sensors were used to monitor zinc ion release events from glucose-stimulated pancreatic cells. The study showed that the zinc ion sensors responded effectively to the release of zinc ions from pancreatic cells at the nanomolar level with high selectivity and rapid subsecond response time.     

InP DHBT-based distributed amplifier for 100 Gbit/s modulator driver operation

A distributed amplifier for use as a modulator driver in next generation optical data communication systems has been manufactured using InP double-hetero bipolar transistor (DHBT) technology with an emitter size of 0.7 times 1 mum². The amplifier achieved a gain of 21 dB and a 3 dB bandwidth of 120 GHz, resulting in a gain-bandwidth product of 1.35 THz. Clearly open 100 Gbit/s 231/1 non-return-to-zero pseudorandom bit sequence (NRZ PRBS) eye diagrams with an output voltage swing of 2.3 V have been measured.     

Role of the stress-activated protein kinases in endothelin-induced cardiomyocyte hypertrophy

3-beta-Hydroxysteroid dehydrogenase (3-beta-HSD) activity coded for by the A44L gene of vaccinia virus (VV) was demonstrated in CV-1 cultures infected by all five VV strains tested, viz. WR, Praha virus, DRYVAX Wyeth-derived virus (DD), LIVP and MVA. Deletion of the A44L gene in two Praha virus-derived clones (the moderately virulent P13 and the highly attenuated P20), the WR and DD viruses resulted in absence of 3-beta-HSD activity from infected cultures. The virulence for mice of P13 was not affected, and that of WR was only slightly decreased, by the A44L gene deletion. Recombinant VVs expressing either varicella-zoster virus glycoprotein E (VZV-gE) or hepatitis B virus preS2-S protein (HBV-preS2-S) and their respective A44L deleted mutants were used in immunogenicity tests in mice. In terms of antibody response to VV and the recombinant proteins, the deletion resulted in a lowering the immunogenicity in the moderately virulent clone P13 virus and its progenies. In the highly attenuated P20 and DD viruses and their progenies no effects were apparent.     

Wavelength tuning of high-speed InGaAs-GaAs-AlGaAs pseudomorphicMQW lasers via impurity-free interdiffusion

The impurity-free interdiffusion technique has been utilized to modify the operating wavelength of high-speed In_0.3Ga_0.65As-GaAs multiple quantum well lasers. Modulation bandwidths of up to 26 GHz (I_bias=50 mA) and modulation current efficiency factors of 5 GHz/mA^1/2 are demonstrated for 3×100 μm² ridge waveguide lasers following wavelength shifts of 32 nm (34 meV). These results demonstrate the feasibility of fabricating monolithic multiple wavelength laser arrays in which each element is capable of low-bias-current direct modulation at bandwidths exceeding 20 GHz     

Reflections on APA divisional structure.

Discusses the divisional structure of the American Psychological Association (APA) and argues that endless numbers of divisions could be created. A revised structure would consist of basic divisions that would be relatively permanent and ad hoc divisions that would be created for a short period and would reflect current, possibly transitory, interests. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cerebral changes in rats exposed individually to an enriched environment.

Gave 275 male Berkeley S1 rats injections of saline or 2mg/kg of methamphetamine. Ss either remained in the home cage or were placed individually into an enriched environment for 2 hr/day during the light or dark hours. Ss placed singly in large enriched-environment cages over a 30-day period were different from home-cage control littermates in weights of brain sections and in brain-enzyme activities. These differences were small, however, unless S's interaction with the stimulus objects was facilitated. Such priming was accomplished by placement in the dark under the influence of methamphetamine. It is concluded that social stimulation, which previously has always been included in the enriched condition, is unnecessary. (25 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prospective sexual behavior.

Discusses W. B. Miller's (see record 1984-17604-001) use of the term "proceptive" in his analysis of reproductive freedom. It is argued that the continuum from contraceptive to proceptive forms only one part of the complex spectrum of human sexual behavior and that, because much of modern human sexuality deliberately avoids conception and reproduction, it is essential to consider the continuum from "conceptive" to "extraceptive" as well. It is suggested that most people will probably exercise some degree of proceptive sex choice as to their offspring when that choice does not require surgical procedures like amniocentesis and when the effectuation does not demand abortion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Idiodynamics vis-à-vis psychology.

Questions the adequacy of the distinction between the nomothetic and idiographic approaches to personality introduced by G. W. Allport (1937) and proposes 3 types of explanatory but complementary norms instead: nomothetic, demographic, and idiodynamic. Idiographic (trait-oriented) and idiodynamic (event-oriented) approaches are differentiated. It is shown that over the past century, psychology, operationally considered, has been a coordinate composite of the other major sciences. Idiodynamics, focusing on the experiential events of a particular personality (idioverse), is at the center of this coordinate gamut. It is proposed that the norms in conjunction with the coordinates be reassembled to conceptualize the parameters of the idioverse. It is suggested that the organic, cultural, and idiodynamic milieus blend through a matrix that produces experiential uniqueness. Three empirical methods for exploring this idioverse are described, including the reciprocity of experimenter–experimentee interaction, self-generated measures for evaluating cognate responses of the same idioverse, and the hermeneutic analysis of 3 levels of communication. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Topograph Bolder: The three-and-six plan for the training of clinical psychologists.

Critiques proceedings of a 1965 conference on training of clinical psychologists and proposes a training plan that provides for (1) a 3-yr MA psychological service worker and (2) a 6-yr PhD specialist. Part 1 of the plan would address the problem of student selection while meeting the social need for a large number of clinical workers in 3, rather than the present 5, yrs. Part 2 of the plan might overcome the competition between clinical psychology and psychiatry. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Submicrometric lipobead-based fluorescence sensors for chloride ion measurements in aqueous solution

This paper describes the preparation and optimization of the analytical properties of fluorescence-based submicrometric chloride ion sensing lipobeads. Fluorescence sensing lipobeads are polystyrene nanoparticles that are coated with a phospholipid membrane that contains a fluorescent indicator for a targeted analyte. In this study, the halide-specific fluorescence dye, lucigenin, was immobilized into the phospholipid membrane of the lipobeads to enable chloride ion detection. The fluorescence intensity of lucigenin decreases with increasing chloride ion concentration due to dynamic quenching. Lipobeads that contained only lucigenin were ineffective as chloride ion sensors due to poor partition of the water-soluble lucigenin molecules into the phospholipid membrane and high leakage rate of immobilized lucigenin molecules to the aqueous solution. To stabilize the chloride ion sensing lipobeads we coimmobilized hexadecanesulfonate molecules into the phospholipid membrane. The formation of ion pairs between hexadecanesulfonate and lucigenin decreased the hydrophilicity of the dye, increased its partition rate into the membrane, increased the brightness of the particles, and significantly decreased the leakage rate of the hydrophobic ion pair from the membrane to the solution. To further improve their chloride ion sensitivity, we also immobilized the chloride ionophore [9] mercuracarborand-3 into the lipobead membrane. The study resulted in a unique submicrometric chloride ion sensor, which is suitable for chloride ion measurements in biological fluids.