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Investigating task-based synchronous computer-mediated communication (SCMC) interaction has increasingly received scholarly attention. However, studies have focused on negotiation of meaning and the quantity, focus and resolution of language related episodes (LREs). This study aims to broaden our understanding of the role of audio, video, and text SCMC conditions by additionally examining second language (L2) learners' levels of engagement during the production of LREs as a result of interactive real-world tasks. We tested 52 dyads of L2 Spanish intermediate learners who completed a decision-making/writing task. Our main analysis revealed that dyads in the audio SCMC condition engaged in more limited LREs vis-à-vis the text SCMC group, and audio SCMC dyads also showed a trend of engaging more in elaborate LREs. The findings imply that interactive SCMC conditions can place differential demands on L2 learners, which has an effect on the ways in which L2 learners address LREs during task-based interaction.

Task-based research has investigated the learning opportunities (e.g. language related episodes) that emerge during heritage and second language learner interactions during writing tasks. However, to date, it is unknown how these peer interactions involving heritage language learners contribute to written texts. Further, given the rise of social technologies in educational settings, a need exists to examine how interactions in digital platforms affect the production of written texts. To address these issues, 13 heritage-second language learner and 16 heritage-heritage learner pairs enrolled in advanced Spanish content courses completed two distinct versions of writing tasks. Participants were instructed that they were hired as business consultants for clothing and cellphone companies in Spain. While each participant wrote her or his own version, the pairs had to interact to compose formal business letters in Spanish to the CEO of each company justifying the hiring (Task A) or laying off (Task B) of employees. The main results first revealed that heritage-heritage pairs produced more syntactically complex business letters, as evidenced by a greater ratio of syntactic subordination along with a minor trend of greater morphosyntactic accuracy. Second, synchronous computer-mediated communication interactions led to a higher production of syntactic coordination, especially for the heritage-second language pairs. Findings are discussed in light of the interplay between learner factors and task environment.

This study investigated the effect of relative humidity (RH) on the chemical composition of gas and particle phases formed from the photooxidation of 1,3-butadiene (13BD) in the presence of NOx under acidified and non-acidified seed aerosol. The experiments were conducted in a 14.5 m3 smog chamber operated in a steady-state mode. Products were identified by high-performance liquid chromatography, gas chromatography–mass spectrometry, and ultrahigh-performance liquid chromatography coupled with high-resolution mass spectrometry. More than 50 oxygenated products were identified, including 33 oxygenated organics, 10 organosulfates (OSs), PAN, APAN, glyoxal, formaldehyde, and acrolein. Secondary organic aerosol (SOA) mass and reaction products formed depended on RH and on the acidity of the seed aerosol. Based on the Extended Aerosol Inorganics Model (E-AIM), the seed aerosol originated from the acidified and non-acidified solutions was found to exist under aqueous and solid phases, respectively. Although the terms "acidified" and "non-acidified" are true for the solutions from which the seeds were atomized, there are far more fundamental differences between the phase states in which species partition to or from (aqueous/solid), which considerably affects their partitioning and formation mechanisms. SOA mass and most SOA products (i) were higher under acidified seed conditions, where the aerosol particles were deliquescent, than under non-acidified seed conditions, where the aerosol particles did not contain any aqueous phase; (ii) increased with the acidity of the aerosol aqueous phase in the experiments under acidified seed conditions; and (iii) decreased with increasing RH. Glyceric acid, threitols, threonic acids, four dimers, three unknowns, and four organosulfates were among the main species measured under either acidified or non-acidified conditions across all RH levels. Total secondary organic carbon and carbon yield decreased with increasing RH under both acidified and non-acidified seed conditions. The photochemical reactivity of 13BD in our systems decreased with increasing RH and was faster under non-acidified than acidified seed conditions. To determine the contribution of 13BD products to ambient aerosol, we analyzed PM2.5 samples collected at three European monitoring stations located in Poland. The occurrence of several 13BD SOA products (e.g., glyceric acid, tartronic acid, threonic acid, tartaric acid, and OSs) in the field samples suggests that 13BD could contribute to ambient aerosol formation. [ABSTRACT FROM AUTHOR]

Individual differences (IDs) largely contribute to success in adult second language attainment (e.g., Dörnyei, 2006). Heritage language (HL) studies have also explored the role of IDs, namely psychosocial variables, and biographical factors with an adult HL learner population. However, the specific contribution of these variables to HL learners' performance on linguistic tests that differ in degree of explicitness and modality remains unknown. Therefore, the current study tested 103 adult HL learners of Spanish who completed a spoken elicited imitation task (EIT) and a written untimed grammaticality judgment task (UGJT) that elicited their knowledge of vulnerable morphosyntactic structures in HL bilingual acquisition. To investigate the contribution of individual learner factors on their performance, participants completed a few questionnaires. Mixed-effects regression models revealed that sequential bilingual status, willingness to communicate, generation and motivation contributed significantly, but yet differentially to participants' performance on grammatical and ungrammatical items of the EIT and UGJT.

This paper presents a comparison between the acoustic scenario at the Rio de Janeiro city center, before and during the COVID-19 pandemic. Undergoing one of the most important pandemics of the recent history, the social isolation led to a new acoustic scenario for Rio de Janeiro. The study was realized at the city center, an area of historical, economic and cultural relevance. The comparison consisted of analyzing measured data and noise maps produced for the city center area. The maps were created according to measured and collected data of the respective time periods. The acoustic scenario prior to the pandemic time was reconstructed based on previous measurements and data collection, while the pandemic one was built with data survey during the highest social isolation index on July 2020. The comparative analysis showed a considerable noise reduction, between 10 and 15 dB, for areas where the traffic noise was not intense and where the human activities were predominant on the streets. However, there was no substantial noise decrease for the areas around the major avenues. This occurred due to the traffic intensity drop to 50% during the pandemic, which meant a noise reduction between 3 and 5 dB.

This study compares metrics for environmental noise diagnosis in schools at airport vicinity. The goal is to analyze and identify the most suitable criteria for scaling aircraft noise impact over schools, during landing and take-off operations. A Brazilian case study is conducted, based on the noise mapping and sound level verification. The day-night average noise level (DNL) and the time above limit (TA) are investigated using acoustic simulation and noise mapping and in order to identify the critical receivers. Results of DNL and TA for two schools at airport surroundings show that the criteria adopted by the municipal and airport authorities to describe the airport noise are unsatisfactory and do not reflect the intermittent behavior of this type of noise. It was verified that individual receiver analysis, based on noise interruptions thought TA parameter is more suitable for evaluation of noise impact over schools at airport vicinity.

The durability of reinforced concrete structures is a significant concern, with corrosion of reinforcement being a leading cause of reduced durability. To ensure accurate models, it is necessary to calibrate or validate them with direct measurements of the structures, specifically monitoring durability-related parameters. The heterogeneity of structures and the dispersion of the parameters considered in models make this calibration or validation essential. To enable the predictive maintenance of structures, it is essential to monitor the parameters related to their durability. This article presents the results of the monitoring of the temperature, corrosion potential, resistivity, and corrosion rate of two structural components, a beam and a tendon, for over 10 months. The obtained values were correlated with the climate to which they were exposed. The corrosion rate can be correlated with the influence of climate, enabling real-time estimation of section loss. This is a necessary step towards the digitization of structures or the development of digital twins that incorporate the effect of corrosion. [ABSTRACT FROM AUTHOR]

Manipulating cognitive demands on second language (L2) tasks, along with the provision of recasts and its effects on L2 development, has motivated recent inquiry within task-based research. However, empirical evidence remains inconclusive as to the impact of task complexity, and it is unknown how it may affect heritage language (HL) development. To address this issue, this study tested 81 adult HL and L2 learners of Spanish. Participants in the experimental conditions completed either a simple or a complex version of a monologic computerized task that delivered written recasts as corrective feedback but differed according to intentional reasoning demands. Participants completed three oral and written assessment tasks to measure development of the Spanish subjunctive in adjectival clauses. Results revealed that the simple group demonstrated greater gains, especially in written production. L2 learners and the HL simple group benefitted more from task-based instruction in comparison to the HL complex group. Findings have implications for the role of prior language experience and task outcomes.

The US Census projects that the Hispanic community in the United States will reach 128.8 million by 2060, and this growth requires a better understanding of Spanish as a heritage language (SHL). This essay examines three future areas of development within SHL instruction. First, more communication between communities of research and practice is necessary to improve classroom instruction. Second, novel SHL teaching materials ought to promote a "pedagogy of multiliteracies" approach. Lastly, we provide a discussion that moves beyond differentiated language instruction by considering SHL at all instructional levels and implementing a "heritage studies" curriculum.

Scholars of task-based language teaching (TBLT) advocate for the identification of learners' communicative needs to inform syllabus design, particularly in language for specific purposes contexts (e.g., Long 2015). However, little research has applied TBLT principles in designing Spanish for specific purposes curricula. Moreover, despite the relationship between learners' task-specific motivation and task performance (e.g., Dörnyei & Kormos 2000; Yanguas 2011), it is unclear how learners respond to the design of tasks derived from a needs analysis. To address this issue, this classroom-based study employed a needs analysis to derive five major exit tasks for syllabus design and measured students' perceptions of exit tasks through microevaluations following Ellis (2011). Adult heritage and second language learners of Spanish (N = 26), enrolled in upper-level university Business Spanish courses in two institutions, rated high levels of motivation for all tasks, but a post-hoc analysis revealed a significantly lower degree of motivation for a task involving the evaluation of a case study. Results imply that conducting a needs analysis and designing exit tasks following TBLT principles appears to be a useful tool to design engaging and relevant tasks, but learners' level of interest and satisfaction can compromise their task-specific motivation.

The demand for Spanish for specific purposes (SSP) university courses in the United States has prompted widespread curricular change in language departments over the last two decades (Klee, 2015; Sánchez-López, 2013). However, many instructors lack the tools and training needed to design SSP curricula that meet learners' communicative needs in such contexts. Moreover, little SSP research to date has taken a task-based approach to identifying learners' specialized needs (Long, 2015), which can provide much-needed support to instructors who are nonexperts in the particular domain of interest. The current study reports on a small-scale, multiphase needs analysis carried out to design a university business Spanish course. In Phase 1, a small sample of business graduates and professionals generated a list of 40 target tasks in the domains of reading, writing, listening, and speaking that were relevant to their particular work. In Phase 2, 54 university business majors rated the frequency and difficulty of each task on a 40-item Likert-type questionnaire. During Phase 3, the researchers analyzed and grouped target tasks identified in the needs assessment to create five major target task types that informed course objectives and classroom tasks.

An evolutionary algorithm was employed to locate the global minimum of Ti O 2 n nanoparticles with n = 2 – 20. More than 61,000 structures were calculated with a semiempirical method and reoptimized using density functional theory. The exciton binding energy of TiO2 nanoparticles was determined through the fundamental and optical band gap. Frenkel exciton energy scales as E B eV = 8.07 / n 0.85 , resulting in strongly bound excitons of 0.132–1.2 eV for about 1.4 nm nanoparticles. Although the exciton energy decreases with the system size, these tightly bound Frenkel excitons inhibit the separation of photogenerated charge carriers, making their application in photocatalysis and photovoltaic devices difficult, and imposing a minimum particle size. In contrast, the exciton binding energy of rutile is 4 meV, where the Wannier exciton energy scales as E B eV = 13.61 μ / ε 2 . Moreover, the Wannier excitons in bulk TiO2 are delocalized according to the Bohr radii: 3.9 nm for anatase and 7.7 nm for rutile. [ABSTRACT FROM AUTHOR]

In this letter, unique extra-long chemically derived pyramidal graphitic ribbons (PGR) were individualized and deposited onto a SiO2 substrate via simple spin-coating. The length of the individualized PGRs was found to exceed the average length of graphene nanoribbons (GNRs) by hundreds of microns. The physicochemical individualization method resulted in the creation of a novel "graphene nanoribbon intercalation compound" (GNRIC), following a strict stoichiometric relation between the GNR powder and alkali metals. Our experiments were conducted with the use of Na and K as intercalants at NaC8, KC8, and KC24 concentrations. Furthermore, we exposed them to THF and discovered that the nanoribbon bundles obtained from CVD bottom-up bulk synthesis of GNRs can be exfoliated. The exfoliated nanoribbons (ex-GNRs) were analyzed using SEM, Raman spectroscopy, optical microscopy, and AFM, revealing the existence of ribbon-like pyramidal nanostructures that are larger than 100 µm. The morphology of these graphitic ribbons, brings a new starting point and immense potential to the development of graphene-based devices for optoelectronics and solar cells. [ABSTRACT FROM AUTHOR]

The durability of reinforced concrete structures exposed to aggressive environments is affected by corrosion of carbon steel reinforcement. For this reason, it is of great practical interest to look for alternative solutions guaranteeing durability through the incorporation of corrosion‐resistant materials, such as stainless steel rebars. This type of steel is specially recommended for structures with a long lifespan, located in aggressive environments, with chlorides or de‐icing salts, and for structures where repair, inspection and rehabilitation is complicated. This solution presents a challenge from the point of view of the materials themselves, the mechanical design and their durability. This article presents the material properties of stainless steel and their influence on concrete structures. Furthermore, it is explained how these properties have been taken into account in the latest draft of the second‐generation Eurocode 2. [ABSTRACT FROM AUTHOR]

Arachis hypogaea L. is an annual legume that is one of the most consumed plant species. On the other hand, it belongs to one of the most monitored clinically important allergens worldwide. The polymorphism of this species based on allergen coding genes could be useful in its characterisation, but previously, no allergen-based marker techniques have been developed for peanuts. A new type of DNA-based markers of coding regions were used to analyse the variability of 21 peanut accessions - BBAP (Bet v1 based amplicon polymorphism), PBAP (profilin based amplicon polymorphism), and VBAP (vicilin based amplicon polymorphism). All of the used technique provided polymorphic fingerprints and distinguished the analysed peanut accessions. The effectivity of these techniques corresponds to the presence of the allergen homologous sequences that are a part of the A. hypogaea genome. VBAP was the most effective in distinguishing the analysed peanut accessions when compared to the results of BBAP and PBAB. For BBAP, two of the analysed accessions provided the same fingerprinting pattern. The ability of the used markers to detect polymorphisms was comparable, with an average polymorphism information content (PIC) value of 0.47. [ABSTRACT FROM AUTHOR]

The generalized cross-correlation with phase transform (GCC-PHAT) algorithm has proved to be useful for blindly estimating the direction of arrival of compact sound sources from microphone array recordings. In applications with distributions of partial sources, such as the tires of vehicles in urban environments, the GCC-PHAT needs to be improved, otherwise the detected sound directions change values between directions of the main sources or correspond to an intermediate value between these directions. This paper presents an extension of the GCC-PHAT, based on post-processing of the output delay matrix and on image processing techniques, in order to separately identify directions of the sound produced by the front and rear tires of moving vehicles. The proposed approach can be extended to identify the tire noise directions produced by vehicles with multiple axles. The algorithm performance is analyzed using pass-by measurements of two-axle vehicles, acquired by a two-microphone array. The experiments were conducted with passenger vehicles of four distinct models, running at different speeds. The experimental results show that the proposed method is able to estimate the vehicle speed with an average error of 10.8 km/h and the vehicle wheelbase with 26 cm on average. A possible application is multiple source characterization for parametric vehicle sound synthesis in auralization.