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Chilling stress impedes growth, development, and productivity of maize (Zea mays L.). MicroRNAs (miRNAs) play critical roles in plant responses to biotic and abiotic stresses at the post-transcriptional level. Although some miRNAs have been identified in maize, little is known about the miRNAs that accumulate differently in the response to chilling stress. In this paper, we combined Illumina sequencing with Northern blot to identify chilling-responsive miRNAs in maize. Novel miRNAs (36) were predicted and some were validated. Twenty-eight known miRNAs and 24 novel miRNAs were found to be differentially expressed under various chilling (6 ºC) treatment times, and most of them were down-regulated after the chilling treatments. Northern blot and real time quantitative polymerase chain reaction proved that miR408b and miRn138 were up-regulated, miR168a, miR529, miRn120, miRn44, and miRn22 were down-regulated, miR166b, miR396c, and miRn59 undulated under 2, 6, and 12 h of the chilling stress. Analysis agriGO based on the target genes of differentially expressed miRNAs indicates that it might change hydrolase and phosphatase activities, nucleic acid metabolisms, and many cellular components to adapt to the chilling stress.

Subject of study. The paper deals with light quality improvement of multi–chip RGB light-emitting diodes (LEDs) and luminaries on their basis. In particular, we have studied the issues of the edge effect reducing, which is non–uniformity of color when observing the source of light under different angles as well as non-uniformity of color distribution on the illuminated surface. Methods. Experimental study of the edge effect has been performed, namely, the analysis of the halo at the periphery of the illuminated area and the non–uniformity of area at the surface of the screen illuminated with RGB LEDs with and without light concentrators. Modeling of illumination distribution at various distances from the source for the system containing four RGB LEDs with reflectors by ZEMAX software has been carried out. Assessment of the uniformity for light distribution via calculating the chromaticity coordinates has been performed. Main results. The possibility of modeling application at the stage of a luminary design is shown on the example of RGB LEDs for assessing the efficiency of light flux usage and colorimetric parameters. Suggested method simplifies significantly the design of luminaries and reduces associated costs. Practical relevance. The findings can be used in the design of luminaries based on RGB LEDs, including the ones with secondary optics elements.

In plant cells, anion channels and transporters are essential for key functions. Members of the chloride channel (CLC) family located in intracellular organelles are required for anion accumulation, pH adjustment, and salt tolerance. Here, we cloned a maize (Zea mays L.) CLC gene, named ZmCLC-d, and found that its transcription was up-regulated under cold, drought, salt, and heat stresses, and after hydrogen peroxide (H2O2) and abscisic acid (ABA) treatments. The overexpression of ZmCLC-d in Arabidopsis conferred tolerance to cold, drought, and salt stresses; this tolerance was primarily displayed by an increased germination rate, root length, plant survival rate, antioxidant enzyme (catalase, peroxidase, and superoxide dismutase) activities, and a reduced accumulation of Cl- in transgenic plants as compared with wild type (WT) plants. The accumulation of H2O2 and superoxide anion in leaves of the ZmCLC-d-overexpressing plants is much less than that of the WT plants. The expressions of some stress related genes, such as CBF1, CBF2, CBF3, DREB2A, and RCI2A, increased to a greater extent in the ZmCLC-d-overexpressing plants than in the WT. Our results strongly suggest that ZmCLC-d played an important role in stress tolerance.

The human brain is an extremely complex system of 1010–1011 neurons. To construct brain-like neuromorphic hardware, the neuron unit should be implemented effectively. Here, we report a neuron transistor based on a MoS2 flake, which has summation and threshold functions similar to biological neurons and may act as a basic neuron unit in neuromorphic hardware. The neuron transistor is composed of a floating gate and two control gates. A heavily doped silicon substrate serves as the floating gate, while the two control gates are capacitively coupled with the floating gate. The neuron transistor can be well controlled by the two control gates individually or simultaneously. The drain current can be modulated by the input voltages at the control gates. While the current response of the neuron transistor has a large dependence on the magnitude of the input signal, it shows little dependence on the frequency of the input signal. To demonstrate the potential neuromorphic application of the neuron transistor, functions including abacus-like function, AND logic and OR logic are realized in the neuron transistor. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Endoscopic vs. laparoscopic gastrojejunostomy for duodenal obstruction: a randomized study in a porcine model" by D. von Renteln and colleagues in the 2012 issue.