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The aim of this research was to synthesize and characterize pure and magnesium chloride(MgCl2) doped L–alanine cadmium chloride (LACC) single crystals. Pure and MgCl2doped LACC single crystals were synthesized by solution method with slow evaporation solution growth technique at room temperature. The single crystal X-ray diffraction studies of pure, 1 and 2 mol% MgCl2doped LACC single crystals revealed monocliniccrystal structure with C2 space group. The optical properties of pure and MgCl2dopedLACC single crystals investigated by UV–VIS/NIR spectrometer confirmed that the crystals were transparent in the wavelength range of 230-1100nm. The optical band gap energy of pure and doped LACC single crystals were found to have the same value of 5.4eV. The energy-dispersive X-ray analysis indicated the incorporation of magnesium and chlorine atoms in an LACC single crystal. The second harmonic generation efficiency of 1 and 2 mol% MgCl2doped LACC crystals were analyzed by Kurtz-Perry powder technique and found to be 1.75 and 2 times greater than that of the standard potassium dihydrogen phosphate crystal,respectively

The aim of this research was to synthesize and characterize pure and magnesium chloride (MgCl2) doped L–alanine cadmium chloride (LACC) single crystals. Pure and MgCl2 doped LACC single crystals were synthesized by solution method with slow evaporation solution growth technique at room temperature. The single crystal X-ray diffraction studies of pure, 1 and 2 mol% MgCl2 doped LACC single crystals revealed monoclinic crystal structure with C2 space group. The optical properties of pure and MgCl2 doped LACC single crystals investigated by UV–VIS/NIR spectrometer confirmed that the crystals were transparent in the wavelength range of 230-1100 nm. The optical band gap energy of pure and doped LACC single crystals were found to have the same value of 5.4 eV. The energy-dispersive X-ray analysis indicated the incorporation of magnesium and chlorine atoms in LACC single crystal. The second harmonic generation efficiency of 1 and 2 mol% MgCl2 doped LACC crystals were analyzed by Kurtz-Perry powder technique and found to be 1.75 and 2 times greater than that of the standard potassium dihydrogen phosphate crystal, respectively.

Abstract Visual deprivation in childhood can lead to lifelong impairments in multisensory processing. Here, the Size-Weight Illusion (SWI) was used to test whether visuo-haptic integration recovers after early visual deprivation. Normally sighted individuals perceive larger objects to be lighter than smaller objects of the same weight. In Experiment 1, individuals treated for dense bilateral congenital cataracts (who had no patterned visual experience at birth), individuals treated for developmental cataracts (who had patterned visual experience at birth, but were visually impaired), congenitally blind individuals and normally sighted individuals had to rate the weight of manually explored cubes that differed in size (Small, Medium, Large) across two possible weights (350 g, 700 g). In Experiment 2, individuals treated for dense bilateral congenital cataracts were compared to sighted individuals in a similar task using a string set-up, which removed haptic size cues. In both experiments, indistinguishable SWI effects were observed across all groups. These results provide evidence that early aberrant vision does not interfere with the development of the SWI, and suggest a recovery of the integration of size and weight cues provided by the visual and haptic modality.

Summary: To clarify the role of sensory experience during early development for adult multisensory learning capabilities, we probed audiovisual spatial processing in human individuals who had been born blind because of dense congenital cataracts (CCs) and who subsequently had received cataract removal surgery, some not before adolescence or adulthood. Their ability to integrate audio-visual input and to recalibrate multisensory spatial representations was compared to normally sighted control participants and individuals with a history of developmental (later onset) cataracts. Results in CC individuals revealed both normal multisensory integration in audiovisual trials (ventriloquism effect) and normal recalibration of unimodal auditory localization following audiovisual discrepant exposure (ventriloquism aftereffect) as observed in the control groups. In addition, only the CC group recalibrated unimodal visual localization after audiovisual exposure. Thus, in parallel to typical multisensory integration and learning, atypical crossmodal mechanisms coexisted in CC individuals, suggesting that multisensory recalibration capabilities are defined during a sensitive period in development.

Typical human perception features stable biases such as perceiving visual events as later than synchronous auditory events. The origin of such perceptual biases is unknown. To investigate the role of early sensory experience, we tested whether a congenital, transient loss of pattern vision, caused by bilateral dense cataracts, has sustained effects on audio-visual and tactile-visual temporal biases and resolution. Participants judged the temporal order of successively presented, spatially separated events within and across modalities. Individuals with reversed congenital cataracts showed a bias towards perceiving visual stimuli as occurring earlier than auditory (Expt. 1) and tactile (Expt. 2) stimuli. This finding stood in stark contrast to normally sighted controls and sight-recovery individuals who had developed cataracts later in childhood: both groups exhibited the typical bias of perceiving vision as delayed compared to audition. These findings provide strong evidence that cross-modal temporal biases depend on sensory experience during an early sensitive period.