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Unique Physical (unique + physical)
Selected AbstractsBiopsychosocial Approach to Treating Self-Injurious Behaviors: An Adolescent Case StudyJOURNAL OF CHILD AND ADOLESCENT PSYCHIATRIC NURSING, Issue 3 2009Mary Askew DNP TOPIC:, Self-injurious behaviors (SIBs) are a common coping mechanism in the adolescent population. A marked increase in SIB has been seen in recent years, yet effective treatment remains elusive. PURPOSE:, This study aims to review current theoretical perspectives and treatment options that reflect a biopsychosocial framework. SOURCES:, Selected multidisciplinary literature related to SIB. CONCLUSIONS:, A 6-month multidisciplinary approach targeting the unique physical, emotional, and social needs of a 14-year-old girl in residential treatment led to the complete cessation of SIB. [source] Exploration of the morphological transition phenomenon of polyaniline from microspheres to nanotubes in acid-free aqueous 1-propanol solution in a single polymerization processPOLYMER INTERNATIONAL, Issue 9 2010Yu-Fong Huang Abstract Polyaniline micro- or nanostructures have been widely investigated due to their unique physical and chemical properties. Although several studies have reported the synthesis of polyaniline microspheres and nanotubes, their mechanisms of formation remain controversial. This study reports our observation of the morphological transition of polyaniline from microspheres to nanotubes in a single polymerization process and also tries to propose their mechanisms of formation. The polymerization of aniline monomer in acid-free aqueous 1-propanol solutions (1 and 2 mol L,1) produces polyaniline microspheres and nanotubes at different reaction stages through a morphology transition process with treatment using ultrasound. In the initial reaction stage, Fourier transform infrared spectra indicate that the aniline monomers form phenazine-like units, producing polyaniline microspheres with an outside diameter of 1,2 µm. The hydrogen bonds between 1-propanol and polyaniline serve as the driving force for the polyaniline chains to build microspheres. As the reaction continues, observation indicates the microspheres decompose and reform one-dimensional nanotubes. In this stage, a structure consisting of a head of phenazine-like units and a tail of acid-doping para -linked aniline units develops. The protonation of the para -linked aniline units provides the driving force for the formation of nanotubes through a self-curling process. We report here the unique morphology transition of polyaniline from microspheres to nanotubes in a single polymerization process. The results indicate that the structural change of polyaniline leads to this morphological change. The mechanisms of formation of the microspheres and nanotubes in a polymerization process are also well explained. Copyright © 2010 Society of Chemical Industry [source] Temperature-dependent structural changes in intrinsically disordered proteins: Formation of ,,helices or loss of polyproline II?PROTEIN SCIENCE, Issue 8 2010Magnus Kjaergaard Abstract Structural characterization of intrinsically disordered proteins (IDPs) is mandatory for deciphering their potential unique physical and biological properties. A large number of circular dichroism (CD) studies have demonstrated that a structural change takes place in IDPs with increasing temperature, which most likely reflects formation of transient ,,helices or loss of polyproline II (PPII) content. Using three IDPs, ACTR, NHE1, and Spd1, we show that the temperature-induced structural change is common among IDPs and is accompanied by a contraction of the conformational ensemble. This phenomenon was explored at residue resolution by multidimensional NMR spectroscopy. Intrinsic chemical shift referencing allowed us to identify regions of transiently formed helices and their temperature-dependent changes in helicity. All helical regions were found to lose rather than gain helical structures with increasing temperature, and accordingly these were not responsible for the change in the CD spectra. In contrast, the nonhelical regions exhibited a general temperature-dependent structural change that was independent of long-range interactions. The temperature-dependent CD spectroscopic signature of IDPs that has been amply documented can be rationalized to represent redistribution of the statistical coil involving a general loss of PPII conformations. [source] Size-Dependent Spectroscopic Properties and Thermochromic Behavior in Poly(substituted thiophene) NanoparticlesCHEMPHYSCHEM, Issue 10 2004Naonori Kurokawa Dr. Nanoparticles are attractive nanomaterials, since they exhibit unique physical and chemical properties. We have found that poly(substituted thiophene) nanoparticles, ranging in size from several tens to hundreds of nanometers, exhibit size-dependent characteristic spectroscopic properties and thermochromic behavior, which can be explained by distorted polymer conformations in the surface layer (see graphic). [source] | ||||||||||