Allelic variation of a dehydrin gene cosegregates with chilling tolerance during seedling emergence

Dehydrins (DHNs, LEA D-11) are plant proteins present during environmental stresses associated with dehydration or low temperatures and during seed maturation. Functions of DHNs have not yet been defined. Earlier, we hypothesized that a ≈35-kDa DHN and membrane properties that reduce electrolyte leakage from seeds confer chilling tolerance during seedling emergence of cowpea (Vigna unguiculata L. Walp.) in an additive and independent manner. Evidence for this hypothesis was not rigorous because it was based on correlations of presence/absence of the DHN and slow electrolyte leakage with chilling tolerance in closely related cowpea lines that have some other genetic differences. Here, we provide more compelling genetic evidence for involvement of the DHN in chilling tolerance of cowpea. We developed near-isogenic lines by backcrossing. We isolated and determined the sequence of a cDNA corresponding to the ≈35-kDa DHN and used gene-specific oligonucleotides derived from it to test the genetic linkage between the DHN presence/absence trait and the DHN structural gene. We tested for association between the DHN presence/absence trait and both low-temperature seed emergence and electrolyte leakage. We show that allelic differences in the Dhn structural gene map to the same position as the DHN protein presence/absence trait and that the presence of the ≈35-kDa DHN is indeed associated with chilling tolerance during seedling emergence, independent of electrolyte leakage effects. Two types of allelic variation in the Dhn gene were identified in the protein-coding region, deletion of one Φ-segment from the DHN-negative lines and two single amino acid substitutions.

A longitudinal investigation of self-other discrimination and the emergence of mirror self-recognition

The aim in this study was to investigate the association between infants' developing interest in their self-image and the onset of mirror self-recognition (MSR). A longitudinal study was conducted with 98 infants who were seen at intervals of 3 months from 9-24 months of age. At each session, the infants were administered a preferential-looking test whereby they were presented with a video image of themselves alongside a video image of a same-aged peer in two conditions, unmarked and marked. From the 12-month session onwards, the infants were also administered a version of the standard mark test of MSR. The infants showed a significant preference for looking at images of themselves in both conditions coincident with the onset of MSR. This result indicates that developing an interest in the self-image is an important component in the development of MSR. (C) 2003 Elsevier Science Inc. All rights reserved.

Emergence of episodic future though in pre-school aged children

Three experiments examined the development of episodic future thinking: the ability to think ahead about novel future situations (Atance & O’Neill, 2001). Each experiment used three novel tasks, similar to the Blow Football task used by Russell, Alexis, and Clayton (2010). In each, there was a different table top with two sides. Children played a game on one side of a table, and then were asked to choose a tool to play with a similar game on the other side of the table the next day. For example, children used a toy fishing rod to catch magnetic fish on one side of the table; playing the same game from the other side of the table required a different type of fishing rod. At test, children chose between 2 or 3 tools: a) the tool they used today, b) the tool suitable for the other side (correct) and c) a distractor tool which was not suitable for either side. In Experiment 1, 24 four-year-olds selected 1 out of 2 tools for tomorrow. Children selected the correct item above chance level in all tasks (p < 0.001). In Experiment 2, in which children were not allowed to look at the apparatus when choosing, 21 three-year olds selected 1 out of 2 tools for tomorrow. This group also selected the right tool above chance level in all tasks (p < 0.001).The results of Experiments 1 and 2 imply that 3- and 4-year olds might indeed show episodic future foresight. However, they could have also selected the right tool by default. To control for this, a third tool distractor was introduced in Experiment 3. This time, 3-4 year olds did not perform above chance levels, suggesting that there is an alternative explanation as to why they performed so well in the previous two experiments.

Development of paper-based color test-strip for drug detection in aquatic environment: Application to oxytetracycline

The wide use of antibiotics in aquaculture has led to the emergence of resistant microbial species. It should be avoided/minimized by controlling the amount of drug employed in fish farming. For this purpose, the present work proposes test-strip papers aiming at the detection/semi-quantitative determination of organic drugs by visual comparison of color changes, in a similar analytical procedure to that of pH monitoring by universal pH paper. This is done by establishing suitable chemical changes upon cellulose, attributing the paper the ability to react with the organic drug and to produce a color change. Quantitative data is also enabled by taking a picture and applying a suitable mathematical treatment to the color coordinates given by the HSL system used by windows. As proof of concept, this approach was applied to oxytetracycline (OXY), one of the antibiotics frequently used in aquaculture. A bottom-up modification of paper was established, starting by the reaction of the glucose moieties on the paper with 3-triethoxysilylpropylamine (APTES). The so-formed amine layer allowed binding to a metal ion by coordination chemistry, while the metal ion reacted after with the drug to produce a colored compound. The most suitable metals to carry out such modification were selected by bulk studies, and the several stages of the paper modification were optimized to produce an intense color change against the concentration of the drug. The paper strips were applied to the analysis of spiked environmental water, allowing a quantitative determination for OXY concentrations as low as 30 ng/mL. In general, this work provided a simple, method to screen and discriminate tetracycline drugs, in aquaculture, being a promising tool for local, quick and cheap monitoring of drugs.

A Novel Range Test

In a range test, one party holds a ciphertext and needs to test whether the message encrypted in the ciphertext is within a certain interval range. In this paper, a range test protocol is proposed, where the party holding the ciphertext asks another party holding the private key of the encryption algorithm to help him. These two parties run the protocol to implement the test. The test returns TRUE if and only if the encrypted message is within the certain interval range. If the two parties do not conspire, no information about the encrypted message is revealed from the test except what can be deduced from the test result. Advantages of the new protocol over the existing related techniques are that it achieves correctness, soundness, °exibility, high e±ciency and privacy simultaneously.