Activity-dependent plasticity of synaptic efficacy at inhibitory junctions

Despite a considerable amount of investigation on long-term potentiation, the question of whether this process occurs at inhibitory synapses has remained controversial until studies of these junctions have been achieved in the Mauthner cell of Teleosts. In this preparation, inhibitory long-term potentiation similar to that occurring at hippocampal excitatory synapses has been demonstrated.     

GMSK with limiter-discriminator detector in Nakagami fading channel with and without selection combining

We derive an equation for the bit-error probability (BEP) of Gaussian minimum-shift keying with limiter discriminator detection in Nakagami-m fading channels including selection and switch-and-stay combining. We compute the BEP for various selections of system parameters.     

Author Index

The enantioselective hydrogenation of ethyl benzoylformate to (R)-ethyl mandelate over dihydrocinchonidine (DHCD)-modified Pt/Al₂O₃ catalyst in acetic acid was studied as a function of modifier concentration, hydrogen pressure and reaction temperature. The maximum enantioselectivity obtained under optimized conditions (DHCD concentration 1 mmol dm^-3, 25 bar H₂, 0 °C, AcOH/toluene 1:1) was 98% ee. The difference between the rates of racemic and enantioselective hydrogenation was less significant than in the case of ethyl pyruvate. This indicates that the high reaction rate in the enantioselective heterogeneous hydrogenation of -ketoesters is not a necessary condition of the chiral induction.     

Compressive Properties of Metal Matrix Syntactic Foams in Free and Constrained Compression

Metal matrix syntactic foam (MMSF) blocks were produced by an inert gas-assisted pressure infiltration technique. MMSFs are advanced hollow sphere reinforced-composite materials having promising application in the fields of aviation, transport, and automotive engineering, as well as in civil engineering. The produced blocks were investigated in free and constrained compression modes, and besides the characteristic mechanical properties, their deformation mechanisms and failure modes were studied. In the tests, the chemical composition of the matrix material, the size of the reinforcing ceramic hollow spheres, the applied heat treatment, and the compression mode were considered as investigation parameters. The monitored mechanical properties were the compressive strength, the fracture strain, the structural stiffness, the fracture energy, and the overall absorbed energy. These characteristics were strongly influenced by the test parameters. By the proper selection of the matrix and the reinforcement and by proper design, the mechanical properties of the MMSFs can be effectively tailored for specific and given applications.     

Kenneth E. Moyer (1919-2006).

Presents an obituary for Kenneth E. Moyer. Before becoming an internationally known expert in the field of aggressive behavior, Kenneth Evan (Keck) Moyer held jobs as an acrobat, a physical therapist, and a farmer. He served as a marine in World War II and was a consultant to the Norwegian government. The range of his life experiences amazed his friends, who wondered how he could have done all these things and still have acquired such a breadth of scholarly knowledge. Throughout his life, his scholarly pursuits had practical applications, and his practical endeavors had a scholarly basis. Keck died May 18, 2006, of an apparent heart attack. His son, Robert S. Moyer, a psychologist who recently retired from the faculty of Bates College, and his daughter, Cathy Noblick, a marriage and family counselor in New Jersey, survive him. Also surviving are five grandchildren and four great grandchildren. He was devoted to all of them and to children he supported through international programs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Microwave-Assisted Digestion Using Diluted Nitric Acid for Multi-element Determination in Rice by ICP OES and ICP-MS

In this work, microwave-assisted digestion using the diluted nitric acid procedure for trace elements determination in rice samples by inductively coupled plasma optical emission spectrometry (ICP OES) and inductively coupled plasma mass spectrometry (ICP-MS) was investigated in a multivariate way. The response surface methodology (RSM), based on the Box–Behnken design, was employed to obtain the optimum conditions of the significant parameters. The optimal conditions, for 250 mg of sample, could be obtained at a temperature of 200 °C, digestion time of 20 min, and 4.5 mol L^?1 for nitric acid concentration. The accuracy of the optimized method was evaluated by analysis of the rice flour certified reference materials (NIST SRM 1568a) and spike recoveries. The results showed good agreement with the reference values of the CRM samples. The analytical method was applied to the determination of Al, As, Ca, Cd, Cu, Fe, K, Mg, Mn, Mo, Se, and Zn in rice samples. Considering some critical parameters such as cost, green chemistry, and analyst safety, the proposed method has advantages compared to classical microwave-assisted digestion procedures based on concentrated acids.