Electrical Behaviour of Heterobimetallic [MM′(EtCS2)4] (MM′=NiPd,NiPt, PdPt) and MM′X‐Chain Polymers [PtM(EtCS2)4I] (M=Ni,Pd)

Herein, we report the isolation of new heterobimetallic complexes [Ni_0.6Pd_1.4(EtCS₂)₄] ( 1 ), [NiPt(EtCS₂)₄] ( 2 ) and [Pd_0.4Pt_1.6(EtCS₂)₄] ( 3 ), which were constructed by using transmetallation procedures. Subsequent oxidation with iodine furnished the MM′X monodimensional chains [Ni_0.6Pt_1.4(EtCS₂)₄I] ( 4 ) and [Ni_0.1Pd_0.3Pt_1.6(EtCS₂)₄I] ( 5 ). The physical properties of these systems were investigated and the chain structures 4 and 5 were found to be reminiscent of the parent [Pt₂(EtCS₂)₄I] species. However, they were more sensitively dependent on the localised nature of the charge on the Ni ion, which caused spontaneous breaking of the conduction bands.     

Orienting Tetramolecular G‐Quadruplex Formation: The Quest for the Elusive RNA Antiparallel Quadruplex

DNA and RNA G‐quadruplexes (G4) are unusual nucleic acid structures involved in a number of key biological processes. RNA G‐quadruplexes are less studied although recent evidence demonstrates that they are biologically relevant. Compared to DNA quadruplexes, RNA G4 are generally more stable and less polymorphic. Duplexes and quadruplexes may be combined to obtain pure tetrameric species. Here, we investigated whether classical antiparallel duplexes can drive the formation of antiparallel tetramolecular quadruplexes. This concept was first successfully applied to DNA G4. In contrast, RNA G4 were found to be much more unwilling to adopt the forced antiparallel orientation, highlighting that the reason RNA adopts a different structure must not be sought in the loops but in the G‐stem structure itself. RNA antiparallel G4 formation is likely to be restricted to a very small set of peculiar sequences, in which other structural features overcome the formidable intrinsic barrier preventing its formation.     

On dynamic sliding mode control of nonlinear fractional-order systems using sliding observer

Nonlinear Dynamics - In this study, a new fractional-order dynamic sliding mode control (FDSMC) for a class of nonlinear systems is presented. In FDSMC, an integrator is placed before the input...     

Thermal and pH dual responsive polyurethane/2-(diisopropylamino)ethyl methacrylate hybrids: Synthesis,characterization, and swelling behavior

This article describes the synthesis and characterization of stimuli-sensitive hybrid films using 2-(diisopropylamino)ethyl methacrylate (DPA), and a polyurethane (PU) base on isophorone diisocyanate. Hybrid films with different amounts of DPA present good film and physicochemical properties. Characterization techniques such as Fourier transform infrared, UV–visible, modulate differential scanning calorimetry, and thermogravimetric analysis reveal chemical interactions between PU and DPA groups. Swelling behavior of films shows a dependence on DPA content, pH, and temperature and different mechanisms of water uptake in response to pH and temperature variations. Hybrid systems would allow controlling water absorption not only through pH or temperature but also from the chosen PU/DPA proportion.