Should I keep studying? Consequences of a decision to stop learning in young and older adults

In situations of cognitive overload, the role of a metacognitive decision to stop learning is of utmost importance. We investigated how young and older adults decide to stop learning as a strategy for maximizing memory performance when they face to-be-learned material exceeding their memory capability. People may decide to stop learning for two main reasons: they experience a growing feeling of disfluency as a learning episode progresses and/or they perceive such a decision to be beneficial for future memory performance. In Experiments 1 and 2, participants studied lists of 50 words. The majority of young and older adults stopped learning in conditions where they were allowed to do so. This decision, counterintuitively, decreased the number of recalled words. Crucially, a similar number of young and older adults stopped the presentation of to-be-remembered material, and both age groups suffered comparable consequences in their memory performance. In Experiments 3a and 3b, participants read an experimental scenario and decided whether they would stop learning based on this description alone. People in different age groups predicted their metacognitive decisions similarly. However, participants’ forecasted performance did not reflect the negative influence of these decisions. Regardless of their age, people tend to make a suboptimal decision to stop learning, unaware of its negative consequences. Together, our results suggest that young and older adults can exert metamemory control to similar degrees even though their decisions may not be beneficial for memory performance. (PsycInfo Database Record (c) 2021 APA, all rights reserved

Кількісні залежності «структура – антибактеріальна дія» у ряду N-заміщених амінокислот

The presence of the antibacterial and antifungal activity in derivatives of amino acids is determined by different mechanisms; therefore, a promising field of research is to obtain new N-substituted amino acids and study their antibacterial action.Aim. To determine the quantitative “structure – antibacterial action” relationships in a series of N-substituted amino acids.Materials and methods. The quantitative dependencies of the antibacterial action of the compounds studied on AlogPs values were calculated using the STATISTIKA 8 program.Results and discussion. The satisfactory values of the levels of correlation of AlogPs parameters calculated with the experimental data of the antibacterial activity of N-substituted amino acids against S. aureus, E. coli, P. vulgaris, P. aeruginosa, B. subtilis, and Cl. perfringens are statistically significant. The absence of the relationship between the antibacterial effect against C. albicans and the structure of threonine derivatives may indicate a possible role of the latter in the metabolism of these fungi.Conclusions. The statistically significant correlation values of AlogPs with the values of the antibacterial action of N-substituted amino acids against the microorganisms studied have been determined, and it quantitatively confirms the earlier assumptions of the existence of the “structure – action” relationship in this series of compounds and the degree of its manifestation.Наличие антибактериальной и противогрибковой активности производных аминокислот определяется различными механизмами, поэтому получение новых N-замещенных аминокислот и изучение их антибактериального действия является перспективным направлением исследований.Цель работы – установление количественных соотношений «структура – антибактериальное действие» в ряду N-замещенных аминокислот.Материалы и методы. Расчеты количественных соотношений антибактериального действия исследуемых соединений от значений AlogPs проведены с использованием программы STATISTIСA 8.Результаты и их обсуждение. Удовлетворительные значения уровней корреляций рассчитанных значений AlogPs с экспериментальными данными антибактериальной активности N-замещенных аминокислот относительно S. aureus, E. coli, P. vulgaris, P. aeruginosa, B. Subtilis и Cl. perfringens являются статистически достоверными. Отсутствие связи между антибактериальным действием относительно C. albicans и структурой производных треонина может свидетельствовать о возможной роли последних в метаболизме данных грибов. Выводы. Установлены статистически достоверные значения корреляции показателя AlogPs со значениями антибактериального действия N-замещенных аминокислот относительно исследуемых микроорганизмов, что количественно подтверждает высказанные ранее предположения о наличии связи «структура-действие» в данном ряду соединений и степень ее проявления. Наявність антибактеріальної та протигрибкової активності похідних амінокислот визначається різноманітними механізмами, тому одержання нових N-заміщених амінокислот та вивчення їх антибактеріальної дії є перспективним напрямком досліджень.Мета роботи – встановлення кількісних співвідношень «структура – антибактеріальна дія» у ряду N-заміщених амінокислот.Матеріали та методи. Розрахунки кількісних залежностей антибактеріальної дії досліджуваних сполук від значень AlogPs проведені з використанням програми STATISTIСA 8.Результати та їх обговорення. Задовільні значення рівнів кореляцій розрахованих значень AlogPs з експериментальними даними антибактеріальної активності N-заміщених амінокислот щодо S. aureus, E. coli, P. vulgaris, P. aeruginosa, B. subtilis та Cl. perfringens є статистично достовірними. Відсутність зв’язку між антибактеріальною дією відносно C. albicans та структурою похідних треоніну може свідчити про можливу роль останніх у метаболізмі цих грибів.Висновки. Встановлені статистично достовірні значення кореляції показника AlogPs зі значеннями антибактеріальної дії N-заміщених амінокислот щодо досліджуваних мікроорганізмів, що кількісно підтверджує висловлені раніше припущення стосовно наявності зв’язку «структура-дія» у даному ряду сполук та ступінь його прояву.

Filamentation of focused and collimated laser beams in liquids

Experimental results of investigations into the transformation of the spectral and spatial characteristics of femtosecond collimated and focused Ti:Sapphire-laser beams with wavelengths of 800 and 400 nm upon filamentation in continuous liquid media are presented. It is shown that broadening of the laser pulse spectrum due to phase self-modulation in the medium with a cubic nonlinearity depends on the pulse power and beam diameter. Dependences of the number of filaments, width of laser radiation spectrum, nonlinear focusing distance, and diameter of the filamentation region on the laser pulse power are measured. The existence of a relative power interval in which the explosive growth of the number of filaments occurs, is established. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

Filamentation of collimated Ti:sapphire-laser pulses in the glass

The results of experiments to study the spatial characteristics of multiple filamentation gigawatt laser pulses in the glass are presented. It is shown that with increasing pulse power multiple filamentation region increases in length and diameter, the distribution of filaments within the region has a maximum value when the power > 105 Pcr area filamentation takes the form of a hollow cone, the apex directed to the source of the laser radiation

Multiple filamentation of laser pulses in the glass

Results are presented of experiments on investigation of the spatial characteristics of multi-filamentation region of giga- and terawatt pulses of a Ti:sapphire laser in a glass. Dependences are obtained of the coordinate of the beginning of filamentation region, number of filaments, their distribution along the laser beam axis, and length of filaments on the pulse power. It is shown that with increasing radiation power, the number of filaments in the multi-filamentation region decreases, whereas the filament diameter has a quasiconstant value for all powers realized in the experiments. It is shown that as a certain power of the laser pulse with Gauss energy density distribution is reached, the filamentation region acquires the shape of a hollow cone with apex directed toward the radiation source

Multilingual representations for low resource speech recognition and keyword search

© 2015 IEEE. This paper examines the impact of multilingual (ML) acoustic representations on Automatic Speech Recognition (ASR) and keyword search (KWS) for low resource languages in the context of the OpenKWS15 evaluation of the IARPA Babel program. The task is to develop Swahili ASR and KWS systems within two weeks using as little as 3 hours of transcribed data. Multilingual acoustic representations proved to be crucial for building these systems under strict time constraints. The paper discusses several key insights on how these representations are derived and used. First, we present a data sampling strategy that can speed up the training of multilingual representations without appreciable loss in ASR performance. Second, we show that fusion of diverse multilingual representations developed at different LORELEI sites yields substantial ASR and KWS gains. Speaker adaptation and data augmentation of these representations improves both ASR and KWS performance (up to 8.7% relative). Third, incorporating un-transcribed data through semi-supervised learning, improves WER and KWS performance. Finally, we show that these multilingual representations significantly improve ASR and KWS performance (relative 9% for WER and 5% for MTWV) even when forty hours of transcribed audio in the target language is available. Multilingual representations significantly contributed to the LORELEI KWS systems winning the OpenKWS15 evaluation

Items from Germany-The impact of Rht alleles on cross-pollination efficiency traits with relevance for hybrid breeding in wheat

Hybrid breeding and the ability to exploit heterosis is one of a few high-priority wheat breeding strategies that have the potential to rapidly improve yield and stability. Yield improvements associated with hybrid vigor were demonstrated to be in the order of a 10–25% increase in grain yield as well as improved resistance against biotic/abiotic stresses and grain quality. Faced with these scenarios, the identification of factors affecting the development of hybrid wheats is of fundamental importance in order to accelerate the rate of genetic gain of the crop. Due to the prevalence and usefulness of Rht ‘Green revolution’ dwarfing alleles, it is important to gain a better understanding of how these alleles affect those traits related to the development of hybrid wheat seed production. Up to now, the expected influence of these alleles/ genes on wheat flowering-related traits was evaluated based on mapping populations or genome-wide association studies, without taking into account the actual effect of each Rht allele in particular. In this project, we propose to explore the effect of different Rht alleles using many near-isogenic lines. The experiments were performed at the Leibniz Institute of Plant Genetics and Crop Plant Research (IPK Gatersleben, Germany) and the Faculty of Agricultural Sciences and Forestry (National University of La Plata, Argentina) during three growing seasons. Four sets of NILs carrying the alleles of Rht genes: Rht1 (Rht-B1b/Rht-D1a), Rht2 (Rht-B1a/Rht-D1b), Rht3 (Rht-B1c/Rht-D1a), Rht 1+2 (Rht-B1b/ Rht-D1b), Rht 2+3 (Rht-B1c/Rht-D1b), and rht (tall; Rht-B1a/Rht-D1a) in the genetic backgrounds of the wheat cultivars April Bearded, Bersee, Maris Huntsman, and Maris Widgeon were evaluated. Traits associated with cross-pollination efficiency (flowering date, plant height, spike length, anther extrusion, anther and filament length, and spikelets/spike) were studied. Preliminary results showed that the extreme dwarf alleles Rht3, Rht1+2, and Rht2+3 presented the greatest effects in all the variables analyzed. Plant height showed reductions from 22–25% (Rht1 and Rht2), 50–57% (Rht3 and Rht1+2), and 66% (Rht2+3) compared to rht (tall). Spike length was increased up to 14% (Rht1+2 vs. rht) and 3–9% for the rest of Rht alleles compared to rht, whereas spikelets/spike were increased up to 6% (Rht2+3 vs. rht). In comparison to rht (tall), the floral organs were negatively influenced by Rht alleles; decreases from 8–13% (Rht 1, Rht2, and Rht3) to 17–25% (Rht1+2 and Rht2+3) in anther length, and reductions from 16–44% in filament length were observed. For their part, anthers extrusion decreased between 15–27% (Rht1, Rht2, and Rht3) to 32–35% for Rht1+2 and Rht2+3 compared with that of rht. No significant differences were detected for flowering time among the alleles evaluated. These preliminary results indicate that Rht alleles combination are involved in multiple traits of interest for hybrid wheat production in breeding programs. Moreover, the magnitude of the negative impact of Rht alleles on floral organs depends on the combination of the alleles involved.Fil: Schierenbeck, Matías. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Leibniz Institute Of Plant Genetics And Crop Plant Research.; AlemaniaFil: Börner, A.. Leibniz Institute Of Plant Genetics And Crop Plant Research.; AlemaniaFil: Aleksandrov, V.. No especifíca;Fil: Alqudah, A. M.. No especifíca;Fil: Chebatareva, M. V.. No especifíca;Fil: Esquisabel, E.. No especifíca;Fil: Golik, S. I.. No especifíca;Fil: Kartseva, T.. No especifíca;Fil: Klykov, A. G.. No especifíca;Fil: Pshenichnikova, M. S.. No especifíca;Fil: Röder, V. P.. No especifíca;Fil: Shamanin, L. V.. No especifíca;Fil: Shchukina, M. R.. No especifíca;Fil: Simón, V. I.. No especifíca;Fil: Yakubovskiy, K.. No especifíca;Fil: Zaynali, Nezhad. No especifíca

Event extraction of bacteria biotopes: a knowledge-intensive NLP-based approach

International audienceBackground: Bacteria biotopes cover a wide range of diverse habitats including animal and plant hosts, natural, medical and industrial environments. The high volume of publications in the microbiology domain provides a rich source of up-to-date information on bacteria biotopes. This information, as found in scientific articles, is expressed in natural language and is rarely available in a structured format, such as a database. This information is of great importance for fundamental research and microbiology applications (e.g., medicine, agronomy, food, bioenergy). The automatic extraction of this information from texts will provide a great benefit to the field

A Molecular Study on the Prevalence and Virulence Potential of Aeromonas spp. Recovered from Patients Suffering from Diarrhea in Israel

Background: Species of the genus Aeromonas are native inhabitants of aquatic environments and have recently been considered emerging human pathogens. Although the gastrointestinal tract is by far the most common anatomic site from which aeromonads are recovered, their role as etiologic agents of bacterial diarrhea is still disputed. Aeromonas-associated diarrhea is a phenomenon occurring worldwide; however, the exact prevalence of Aeromonas infections on a global scale is unknown. Methodology/Principal Findings: The prevalence and virulence potential of Aeromonas in patients suffering from diarrhea in Israel was studied using molecular methods. 1,033 diarrheal stools were sampled between April and September 2010 and Aeromonas species were identified in 17 (,2%) patients by sequencing the rpoD gene. Aeromonas species identity and abundance was: A. caviae (65%), A. veronii (29%) and Aeromonas taiwanensis (6%). This is the first clinical record of A. taiwanensis as a diarrheal causative since its recent discovery from a wound infection in a patient in Taiwan. Most of the patients (77%) from which Aeromonas species were isolated were negative for any other pathogens. The patients ranged from 1 to 92 years in age. Aeromonas isolates were found to possess different virulence-associated genes: ahpB (88%), pla/ lip/lipH3/apl-1 (71%), act/hlyA/aerA (35%), alt (18%), ast (6%), fla (65%), lafA (41%), TTSS ascV (12%), TTSS ascF-ascG (12%), TTSS-dependent ADP-ribosylating toxins aexU (41%) and aexT (6%) in various combinations. Most of the identified strain