The postnatal development of orientation and direction selectivity of single cells was examined in the primary visual cortex of rabbits. The percentage of cells which were orientation-selective reached adult levels by day 30, whereas the proportion of cells which were direction-selective did not reach adult levels until day 60. Differences in the time course of development of orientation and direction selectivity, together with data previously reported on differences in the effects of deprivation on orientation and direction selectivity, suggest that (1) different mechanisms underly the organization of orientation and direction selectivity and (2) the critical periods for the effects of deprivation on orientation and direction selectivity reflect the different time course of the normal development of these two response properties.
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http://dx.doi.org/10.1016/0165-3806(88)90145-9 | DOI Listing |
Nat Commun
January 2025
Gene Regulation Laboratory, MRC Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, OX3 9DS, Oxford, UK.
Individual enhancers are defined as short genomic regulatory elements, bound by transcription factors, and able to activate cell-specific gene expression at a distance, in an orientation-independent manner. Within mammalian genomes, enhancer-like elements may be found individually or within clusters referred to as locus control regions or super-enhancers (SEs). While these behave similarly to individual enhancers with respect to cell specificity, distribution and distance, their orientation-dependence has not been formally tested.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
College of Chemistry and Chemical Engineering, Qiqihar University, Qiqihar 161006, PR China; Heilongjiang Provincial Key Laboratory of Catalytic Synthesis for Fine Chemicals, Qiqihar University, Qiqihar 161006, PR China. Electronic address:
The establishment of heterojunctions has been demonstrated as an effective method to improve the efficiency of photocatalytic hydrogen production. Conventional heterojunctions usually have random orientation relationships, and heterointerfaces can hinder photogenerated carrier transport due to larger lattice mismatches, thus reducing the photoelectric conversion efficiency. In this study, a novel Te/InO@MXene lattice coherency heterojunction was prepared by leveraging the identical lattice spacing of InO (222) and Te (021) crystal face.
View Article and Find Full Text PDFJ Phys Chem B
January 2025
Department of Chemistry, Sungkyunkwan University, Suwon 16419, Republic of Korea.
Physical vapor deposition is widely used in the fabrication of organic light-emitting diodes and has the potential to adjust the density and orientation through substrate temperature control, which may lead to enhanced electrical performance. However, it is unclear whether this enhanced property is because of the horizontal molecular orientation or the increased density. The effects of the density and orientation on the electrical properties of a potential electron transport material, (3-dibenzo[c,h]acridin-7-yl)phenyl)diphenylphosphine oxide (TPPO-dibenzacridine), were investigated.
View Article and Find Full Text PDFPolymers (Basel)
January 2025
School of Polymer Engineering, Institute of Engineering, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand.
Poly(lactic acid) (PLA) exhibits excellent shape memory properties but suffers from brittleness and a high glass transition temperature (T), limiting its utility in flexible and durable applications. This study explored the modification of PLA properties through the incorporation of poly(ethylene glycol) (PEG), varying in both content (5-20 wt%) and molecular weight (4000-12,000 g/mol), to enhance its suitability for specific applications, such as medical splints. The PLA/PEG blend, containing 15 wt% PEG and with a molecular weight of 12,000 g/mol, exhibited superior shape fixity (99.
View Article and Find Full Text PDFPolymers (Basel)
January 2025
Faculty of Mechanics, University Politehnica of Timisoara, Piata Victoriei 2, 300006 Timisoara, Romania.
This study investigated silicone composites with distributed boron nitride platelets and carbon microfibers that are oriented electrically. The process involved homogenizing and dispersing nano/microparticles in the liquid polymer, aligning the particles with DC and AC electric fields, and curing the composite with IR radiation to trap particles within chains. This innovative concept utilized two fields to align particles, improving the even distribution of carbon microfibers among BN in the chains.
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