環境音と意味知識の発達との関係：5歳児がインタラクションを通して学ぶもの

It is widely believed among researchers and the general public that a close relationship exists between listening to sounds and language acquisition. However, few studies have presented evidence of this relationship, and none have focused on the effects of collaboration with and among children, which might improve their language-learning abilities. This study tried to determine the extent to which nursery school children could expand their semantic knowledge in their first language by collaborating in a small group after listening to sounds. Twenty-four nursery school children participated in this study. They were divided into eight groups and were asked to listen carefully to two sets of previously prepared sounds, each consisting of four distinct types of sounds. Both sets were developed to tell one story. After listening to all the sound sets, the children were asked to discuss and recall the order and content of each set. They were allowed to speak freely in a peer group and occasionally received positive feedback from the researcher. The results show that all the groups actively discussed and then clearly recalled the order and content of the story by working together. This finding implies that preschool children will likely also expand their semantic knowledge in a second language if input is properly delivered.音と言語獲得との関係は深いと信じられているが、実際には、そのエビデンスを示すものはほとんどない。本研究では、5歳児らが、環境音に耳をすませ、注意を向け、小グループでの話し合いの中で、言語力を伸ばしていくことを確認した。5歳児らは、ピア（仲間）とのインタラクションの中で、聴いた音を再確認し、聴いた音に対して発話する力を高めていくことができた。この研究は、母語のみならず、第二言語における習得にも応用できるかもしれない

Selenite inhibits notch signaling in cells and mice

Selenium is an essential micronutrient with a wide range of biological effects in mammals. The inorganic form of selenium, selenite, is supplemented to relieve individuals with selenium deficiency and to alleviate associated symptoms. Additionally, physiological and supranutritional selenite have shown selectively higher affinity and toxicity towards cancer cells, highlighting their potential to serve as chemotherapeutic agents or adjuvants. At varying doses, selenite extensively regulates cellular signaling and modulates many cellular processes. In this study, we report the identification of Delta–Notch signaling as a previously uncharacterized selenite inhibited target. Our transcriptomic results in selenite treated primary mouse hepatocytes revealed that the transcription of Notch1, Notch2, Hes1, Maml1, Furin and c-Myc were all decreased following selenite treatment. We further showed that selenite can inhibit Notch1 expression in cultured MCF7 breast adenocarcinoma cells and HEPG2 liver carcinoma cells. In mice acutely treated with 2.5 mg/kg selenite via intraperitoneal injection, we found that Notch1 expression was drastically lowered in liver and kidney tissues by 90% and 70%, respectively. Combined, these results support selenite as a novel inhibitor of Notch signaling, and a plausible mechanism of inhibition has been proposed. This discovery highlights the potential value of selenite applied in a pathological context where Notch is a key drug target in diseases such as cancer, fibrosis, and neurodegenerative disorders

Draft Genome Sequence of Burkholderia sp. MR1, a Methylarsenate-Reducing Bacterial Isolate from Florida Golf Course Soil

To elucidate the environmental organoarsenical biocycle, we isolated a soil organism, Burkholderia sp. MR1, which reduces relatively nontoxic pentavalent methylarsenate to the more toxic trivalent methylarsenite, with the goal of identifying the gene for the reductase. Here, we report the draft genome sequence of Burkholderia sp. MR1

A Computation of Bifurcation Parameter Values for Limit Cycles

This letter describes a new computational method to obtain the bifurcation parameter value of a limit cycle in nonlinear autonomous systems. The method can calculate a parameter value at which local bifurcations; tangent, period-doubling and Neimark-Sacker bifurcations are occurred by using properties of the characteristic equation for a fixed point of the Poincaré mapping. Conventionally a period of the limit cycle is not used explicitly since the Poincaré mapping needs only whether the orbit reaches a cross-section or not. In our method, the period is treated as an independent variable for Newton's method, so an accurate location of the fixed point, its period and the bifurcation parameter value can be calculated simultaneously. Although the number of variables increases, the Jacobian matrix becomes simple and the recurrence procedure converges rapidly compared with conventional methods

Glutathione transferases with vanadium-binding activity isolated from the vanadium-rich ascidian Ascidia sydneiensis samea

Some ascidians accumulate vanadium in vanadocytes, which are vanadium-containing blood cells, at high levels and with high selectivity. However, the mechanism and physiological significance of vanadium accumulation remain unknown. In this study, we isolated novel proteins with a striking homology to glutathione transferases (GSTs), designated AsGST-I and AsGST-II, from the digestive system of the vanadium-accumulating ascidian Ascidia sydneiensis samea, in which the digestive system is thought to be involved in vanadium uptake. Analysis of recombinant AsGST-I confirmed that AsGST-I has GST activity and forms a dimer, as do other GSTs. In addition, AsGST-I was revealed to have vanadium-binding activity, which has never been reported for GSTs isolated from other organisms. AsGST-I bound about 16 vanadium atoms as either V(IV) or V(V) per dimer, and the apparent dissociation constants for V(IV) and V(V) were 1.8 × 10-4 M and 1.2 × 10-4 M, respectively. Western blot analysis revealed that AsGSTs were expressed in the digestive system at exceptionally high levels, although they were localized in almost all organs and tissues examined. Considering these results, we postulate that AsGSTs play important roles in vanadium accumulation in the ascidian digestive system

Antimicrobial Activity of Metals and Metalloids

Competition shapes evolution. Toxic metals and metalloids have exerted selective pressure on life since the rise of the first organisms on the Earth, which has led to the evolution and acquisition of resistance mechanisms against them, as well as mechanisms to weaponize them. Microorganisms exploit antimicrobial metals and metalloids to gain competitive advantage over other members of microbial communities. This exerts a strong selective pressure that drives evolution of resistance. This review describes, with a focus on arsenic and copper, how microorganisms exploit metals and metalloids for predation and how metal- and metalloid-dependent predation may have been a driving force for evolution of microbial resistance against metals and metalloids.BFU2016-75425-P (70% FEDER), PID2020-112634GB-I0

Chemical synthesis of the organoarsenical antibiotic arsinothricin

We report two routes of chemical synthesis of arsinothricin (AST), the novel organoarsenical antibiotic. One is by condensation of the 2-chloroethyl(methyl)arsinic acid with acetamidomalonate, and the second involves reduction of the N-acetyl protected derivative of hydroxyarsinothricin (AST-OH) and subsequent methylation of a trivalent arsenic intermediate with methyl iodide. The enzyme AST N-acetyltransferase (ArsN1) was utilized to purify l-AST from racemic AST. This chemical synthesis provides a source of this novel antibiotic for future drug development