Spontaneous Production Research Articles

The Effect of Various Types of Mother Stress on the Some Components of the Brain Redox System in Male and Female Rats on the 20th Day of the Embryonic Development Period

The effect of prenatal stress, post-traumatic stress disorder, and their combined effect in rat mothers on the condition of the pituitary-adrenal system and the brain redox balance in 20-day-old embryos was studied. Mother’s prenatal stress result in increase the level’s corticosterone in the blood and decrease the level of reduced glutathione in the brain of male embryos. In female embryos, the level of Fenton-induced products of proteins oxidative modification increased and the reduced glutathione level in the brain decreased. Modeling of post-traumatic stress disorder in mother result in an increase in the corticosterone level in the blood, and a decrease in the level of Fenton-induced products of proteins oxidative modification in the brain of male embryos. In female embryos, the levels of products of spontaneous and Fenton-induced oxidative modifications of proteins in the brain increased. The combined effect of two types of stress in mother result in an increase in levels corticosterone in the blood, a decrease in the spontaneous products level and an increase in Fenton-induced products level of proteins oxidative modifications, and a decrease in the reduced glutathione level in the male embryos brain. In female embryos, all the studied indicators of proteins oxidative modification products in the brain increased. Thus, all three studied types of stress in the mother cause changes in the hypothalamic-pituitary-adrenal system and in the brain redox balance in 20-day-old embryos. These changes are different in male and female embryos, and in most of the studied indicators, the pattern of differences is inverted in relation to the control group. Such changes at embryos can result in negative changes in the neuronal organization in adult offspring of stressed rat mothers.

Achieving Excess Hydrogen Output via Concurrent Electrochemical and Chemical Redox Reactions on P-Doped Co-Based Catalysts with Electron Manipulation and Kinetic Regulation.

Electrolytic hydrogen production is of great significance in energy conversion and sustainable development. Traditional electrolytic water splitting confronts high anode voltage with oxygen generation and the amount of hydrogen produced at cathode depends entirely on the quantity of electric charge input. Herein, excess hydrogen output can be achieved by constructing a spontaneous hydrazine oxidation reaction (HzOR) coupled hydrogen evolution reaction (HER) system. For the hydrazine oxidation-assisted electrolyzer in this work, both the external input electrons and the electrons produced by spontaneous chemical redox reaction can reduce water, producing more hydrogen than traditional electrolytic water splitting system. The ultrafast kinetics of bifunctional P-doped Co-based catalysts plays a key role in the spontaneous feature of HzOR/HER redox reaction and low working voltage of hydrazine oxidation-assisted electrolyzer (12 mV@100mA cm-2). Theoretical calculation results and ex situ/in situ spectra demonstrate that doped P could optimize electronic structure, regulate adsorption energy of intermediates, and thus endows catalysts with ultrafast kinetics. This work provides a new pathway for the development of spontaneous oxidation-assisted hydrogen production, to achieve excess hydrogen output via concurrent electrochemical and chemical redox reactions.

Heritage Spanish in Montreal: An Analysis of Clitics in Spontaneous Production Data

This study investigates clitic use in adult heritage speakers (HL speakers) of Spanish, with French as their dominant language. We conducted an exploratory case study using spontaneous production data from HL speakers of Spanish and first-generation Spanish immigrants living in Montreal, Canada. Data were collected through two guided production tasks, one oral and one written, to account for task-induced performance variations. Our analysis focused on clitic production, omission, function, optionality, and grammaticality. The findings reveal both similarities and differences compared to monolingual native Spanish speakers, highlighting a broad range of clitic structures produced by all participants and a potential tendency among HL speakers to favour fixed choices in optional structures. This study provides valuable insights into the production patterns of clitics in adult HL speakers of Spanish with French as their dominant language, contributing to our understanding of bilingual grammar.

Determination of spontaneous and stimulated cytokine production in cell culture in patients with COVID-19 associated multisystem inflammatory syndrome

To date, the pathogenesis of COVID-19 associated multisystem inflammatory syndrome (MIS-C) remains unclear. Despite this, it becomes obvious that the pathogenesis of MIS-C is directly related to a certain immune dysregulation, however, a clear understanding of the mechanisms of this dysregulation has not yet been formulated. In order to identify the cytokine profile in patients with MIS-C, spontaneous and stimulated production of certain cytokines in cell culture was identified. Materials and methods. The study was conducted in the following study groups: group 1 — patients with MIS-C (n = 52); group 2 (comparison group) — patients with COVID-19 associated pneumonia (n = 15); group 3 (control group) — conditionally healthy patients (n = 23). The following stimulating agents were used: S58 — recombinant antigen Spike_SARS-Cov-2; NP is a recombinant NP antigen of the coronavirus SARS-CoV-2 and a standard mitogen. Results. Тhe absence of the initially expected hyperproduction of the main pro-inflammatory cytokines (IL-6, IL-8, TNF-α, etc.) was recorded. Statistically significant developments were recorded between patients of the study groups in the spontaneous production of MCP-1, in particular, the indicated indicator was 40010.82 (19698.1; 64812.1); 643.7 (214.6; 1695.4) and 622.7 (214.6; 1068.1), respectively. The indicated spontaneous hyperproduction of MCP-1 in patients with MIS-C allows us to consider as a probable completely new theory of the pathogenesis of MIS-C associated with dysregulation of the type 2 immune response. The presence of statistically significant differences, primarily in the spontaneous production of this cytokine, can apparently be explained by the presence of genetically determined determinants associated with subsequent dysfunction of the Th2 helper immune response, a potential trigger for which is a previous COVID-19 infection. Thus, further study of the immunopathogenesis of COVID-19 associated MIS-C is required.

A quick response, but not too much: Experienced mangabeys (Cercocebus torquatus) lose interest in contact call exchanges that do not respect this "conversational rule".

Several non-human primate species engage in vocal exchanges of contact calls, throughout the day in peaceful contexts. These vocal exchanges have been compared to human conversations because vocalizations are uttered in turn-taking: a temporal pattern where interlocutors minimize silences and avoid overlaps. But observing such a pattern in the spontaneous production of a species, as is the case with red-capped mangabeys (Cercocebus torquatus), is not enough to make it a rule. Another prerequisite is that the pattern is expected by the animal. Here, we conducted a playback experiment using the violation-of-expectation paradigm to test whether captive red-capped mangabeys react differently to usual vs unusual interactive temporal patterns. We played back vocal exchanges with usual minimized response time (0.5 sec), with unusual longer response time (1.5 sec) and with unusual call overlap to 12 adult captive male mangabeys. For each individual, we measured the occurrences and durations of head orientation toward the loudspeaker after the stimuli. The interest of individuals varied according to the vocal exchange temporal pattern in interaction with their age. Indeed, the older (and thus more socially experienced) an individual was, the less interested he became after an unusual vocal exchange, i.e. a vocal exchange with call overlap or with a delayed response time. These findings suggest that experience shapes attention towards more socially relevant situations, and thus that turn-taking can be qualified as a social rule.

Soybean Bradyrhizobium spp. Spontaneously Produce Abundant and Diverse Temperate Phages in Culture.

Soybean bradyrhizobia (Bradyrhizobium spp.) are symbiotic root-nodulating bacteria that fix atmospheric nitrogen for the host plant. The University of Delaware Bradyrhizobium Culture Collection (UDBCC; 353 accessions) was created to study the diversity and ecology of soybean bradyrhizobia. Some UDBCC accessions produce temperate (lysogenic) bacteriophages spontaneously under routine culture conditions without chemical or other apparent inducing agents. Spontaneous phage production may promote horizontal gene transfer and shape bacterial genomes and associated phenotypes. A diverse subset (n = 98) of the UDBCC was examined for spontaneously produced virus-like particles (VLPs) using epifluorescent microscopy, with a majority (69%) producing detectable VLPs (>1 × 107 mL-1) in laboratory culture. Phages from the higher-producing accessions (>2.0 × 108 VLP mL-1; n = 44) were examined using transmission electron microscopy. Diverse morphologies were observed, including various tail types and lengths, capsid sizes and shapes, and the presence of collars or baseplates. In many instances, putative extracellular vesicles of a size similar to virions were also observed. Three of the four species examined (B. japonicum, B. elkanii, and B. diazoefficiens) produced apparently tailless phages. All species except B. ottawaense also produced siphovirus-like phages, while all but B. diazoefficiens additionally produced podovirus-like phages. Myovirus-like phages were restricted to B. japonicum and B. elkanii. At least three strains were polylysogens, producing up to three distinct morphotypes. These observations suggest spontaneously produced phages may play a significant role in the ecology and evolution of soybean bradyrhizobia.

Bimodal aphasia and dysgraphia: Phonological output buffer aphasia and orthographic output buffer dysgraphia in spoken and sign language

We report a case of crossmodal bilingual aphasia—aphasia in two modalities, spoken and sign language—and dysgraphia in both writing and fingerspelling. The patient, Sunny, was a 42 year-old woman, after a left temporo-parietal stroke, a speaker of Hebrew, Romanian, and English and an adult learner, daily user of Israeli Sign language (ISL).We assessed Sunny's spoken and sign languages using a comprehensive test battery of naming, reading, and repetition tasks, and also analysed her spontaneous-speech and sign. Her writing and fingerspelling were assessed using tasks of dictation, naming, and delayed copying.In spoken language production, Sunny showed a classical phonological output buffer (POB) impairment in naming, reading, repetition, and spontaneous production, with phonological errors (transpositions, substitutions, insertions, and omissions) in words and pseudo-words, and whole-unit errors in morphological affixes, function-words, and number-words, with a length effect. Importantly, her error pattern in ISL was remarkably similar in the parallel tasks, with phonological errors in signs and pseudo-signs, affecting all the phonological parameters of the sign (movement, handshape, location, and orientation), and whole-unit errors in morphemes, function-signs, and number-signs. Sunny's impairment was selective to the POB, without phonological input, semantic-conceptual, or syntactic deficits. This shows for the first time how POB impairment, a kind of conduction aphasia, manifests itself in a sign language, and indicates that the POB for sign-language has the same cognitive architecture as the one for spoken language. It may also indicate similar neural underpinnings for spoken and sign languages.In writing, Sunny forms the first case of a selective type of dysgraphia in fingerspelling, orthographic (graphemic) output buffer dysgraphia. In both writing and fingerspelling, she made letter errors (letter transpositions, substitutions, insertions, and omissions), as well as morphological errors and errors in function words, and showed length effect. Sunny's impairment was selective to the orthographic output buffer, whereas her reading, including orthographic input processing, was intact. This suggests that the orthographic output buffer is shared for writing and in fingerspelling, at least in a late learner of sign language. The results shed further light on the architecture of phonological and orthographic production.

Exploring Students’ Perceptions of Role-Playing Activities in Boosting English Speaking Confidence

This study explores students’ perceptions of role-playing as a pedagogical approach in language learning. A questionnaire was administered to 112 participants to gauge their views on the effectiveness of role-playing in enhancing language proficiency. The results indicate a generally favorable perception among students, highlighting role-playing’s ability to simulate real-life situations, promote engagement, and foster creativity in language use. Participants reported that role-playing activities effectively facilitated the practice of spontaneous language production and enhanced student engagement. Various types of role-playing activities were evaluated, revealing that scripted role-playing increased confidence, semi-scripted formats supported the use of set phrases, and improvised role-plays improved fluency. Additionally, students recognized benefits such as improved speaking fluency and pronunciation. However, challenges such as performance anxiety and time management issues were also identified. This research highlights the significant potential of role-playing in language education while addressing the associated challenges, suggesting that careful implementation can maximize its benefits.

Microfluidics-Assisted Polymer Vesicle Budding in Emulsion Systems: A Promising Approach for the Preparation and Application of Polymer Vesicles

The challenge of producing polymer vesicles remains difficult, despite numerous attempts to modulate the kinetics of polymer vesicle budding and achieve precise control over the membrane characteristics. An innovative approach that incorporates the use of copolymer-loaded single-emulsion droplets is proposed to address this challenge. This method enables the precise manipulation of micelles and polymer vesicles’ composition, structures and dimensions. The emulsion contracts and forms microspheres when the copolymer concentrations exceed > 0.5 wt%, resulting in the formation of nano polymer vesicles. Conversely, the copolymer spontaneously forms micro polymer vesicles and micelles through vesicle budding at lower concentrations. The spontaneous production of vesicles and micelles can be induced by modifying the copolymer concentration in the emulsion. Our discoveries have a significant impact relative to the development of copolymer membranes and contribute to an enhanced comprehension of the mass manufacturing of polymer vesicles from single emulsions.

Spontaneous Production of H2O2 at the Liquid-Ice Interface: A Potential Source of Atmospheric Oxidants.

We present experimental evidence for the spontaneous production of hydrogen peroxide (H2O2) at the liquid-ice interface during the freezing of dilute salt solutions. Specifically, sample solutions containing NaCl, NaBr, NH4Cl, and NaI at concentrations between 10-6 and 10-1 M were subjected to freezing-melting cycles and then analyzed for H2O2 content. The relationship between the production rate of H2O2 and the salt concentration follows that of the Workman-Reynolds freezing potential (WRFP) values as a function of the salt concentration. Our results suggest that H2O2 is formed at the liquid-ice interface from the self-recombination of hydroxyl radicals (OH·), produced from the oxidation of hydroxide anions due to the high electric field generated at the aqueous-ice interface under the WRFP effect. Furthermore, the involvement of O2 likely acting as an electron capturer could promote to produce more OH radicals and hydroperoxyl radicals (HO2·), thus enhancing the production of H2O2 at the liquid-ice interface. Overall, this study suggests a novel mechanism of H2O2 formation in ice via its spontaneous production at the liquid-ice interface, induced by the Workman-Reynolds effect.

7640 The first description of an MC4R variant in a patient with Kallmann syndrome and obesity

Abstract Disclosure: A.A. Aslam: None. S. Lim: None. R. Willemsen: None. K. Koysombat: None. M. Young: None. W.S. Dhillo: None. A. Abbara: None. S. Howard: None. E.F. Gevers: None. Introduction: Pathogenic MC4R gene variants result in hyperphagia and early onset obesity but puberty is not usually affected. We describe an MC4R variant in a patient with Kallmann syndrome and obesity. A 16 year old male with repaired Tetralogy of Fallot, anosmia, autism and anxiety, was referred with obesity and delayed puberty. His birth weight was 3360 g (-0.26 SDS). Height was -1.31 SDS, BMI 30.7 kg/m2. He had high arched palate, normal skin and hair colour, mild hypertelorism and upward slanting palpebral fissures. Pubertal staging was A2P1G1 5ml testes bilaterally. Results: LHRH test showed borderline low peaks (LH 5.0 U/L, FSH 2.6 U/L) and inhibin B 108 pg/mL (25-325 pg/mL). MRI brain showed hypoplastic olfactory bulbs, absent olfactory sulci and normal pituitary anatomy. CGH microarray, karyotype and the UK hypogonadism gene panel were normal. He underwent whole genome sequencing in the Genetic Factors Affecting the Timing of Puberty Study; no abnormalities in 52 known genes associated with GnRH deficiency were found but a previously described heterozygous variant was detected, MC4R c.542G>A, p.Gly181Asp, classified pathogenic and absent in control databases. Management: He was commenced on Testosterone but showed progression of testicular size to 10 mL and testosterone was stopped but required restarting. Repeat investigations off treatment, aged 22 years (height 178 cm, BMI 42 kg/m2, testes 15 mL): inhibin B 66 pg/mL, testosterone 2 nmol/L, baseline LH 2.4 U/L, stimulated peak 24.9 U/L, baseline FSH 1.2 U/L, stimulated peak 4.2 U/L. Cortisol and IGF1 were in the normal range. He also developed autoimmune hypothyroidism with raised TPO antibodies (TSH 24.7 mU/L, FT4 5.6 pmol/L). Discussion: Previous in vitro work has shown complete loss of function of MC4R p.Gly181Asp due to reduced cell surface expression and reduced binding to a-MSH. Heterozygous p.Gly181Asp variants have been described in several children/adults with obesity; but hypogonadism in heterozygous carriers has not. Homozygous MC4R p.Gly181Asp was found in a male with obesity and partial HH thought to be due to abnormal GnRH production but with normal olfactory bulbs. We are the first to describe a heterozygous MC4R p.Gly181Asp variant in a patient with partial hypogonadism and anosmia with hypoplastic bulbs in addition to obesity. Interaction between POMC-MC-leptin circuits and Kisspeptin-GnRH circuits is recognised although not completely understood. Previous work has shown that a subset of kisspeptin neurons express MC4R and that KNDy neurones receive synaptic input from POMC neurons. In addition, inhibition of MC4R/MC3R results in delayed onset of puberty in rats. Our results support a role for MC4R in GnRH secretion and potentially olfactory /GnRH neuronal migration. Assessment of spontaneous gonadotrophin production and response of gonadotrophin production to kisspeptin stimulation is currently in progress. Presentation: 6/1/2024

Antithrombin regulates neutrophil activities through the stimulation of C-type lectin family 1A

AbstractIt has been suggested that a serine proteinase inhibitor, antithrombin (AT), exerts anti-inflammatory effects on different types of cells, independent of thrombin inhibition. In this study, we aimed to identify a specific receptor for AT by a screening method using a transmembrane–tethered AT ligand expressed on HEK293T cells together with the coexpression of candidate receptors, followed by the immunoprecipitation of a complex of AT ligand with a receptor. We identified C-type lectin family 1A (CLEC1A) as a receptor for AT. We confirmed the binding of AT to the extracellular domain of CLEC1A using surface plasmon resonance. Recombinant as well as native AT concentration-dependently induced the rounding of purified human neutrophils in shape, associated with the suppression of spontaneous reactive oxygen species production in vitro, but argatroban did not, indicating the independence of AT effects on thrombin inhibition. Native AT maintained the passage of neutrophils through the artificial microcapillaries. Both AT enhanced the phagocytosis of pHrodo-labeled Escherichia coli and prolonged the viability of the neutrophils. The cellular effects of AT were similar to those of histidine-rich glycoprotein, which has the same CLEC1A as a receptor, and were partially inhibited by the addition of anti-CLEC1A antibody to the incubation media. These results suggested that CLEC1A is a novel receptor for AT, and the stimulation of CLEC1A by AT at least in part mediates the important functional changes of human neutrophils.

Task complexity effects on L2 speech rhythm in spontaneous speech production

Task-based pronunciation teaching studies have shown that the cognitive complexity of a task affects different aspects of second language (L2) speech, such as vowel accuracy and comprehensibility. However, its impact on L2 speech rhythm is still under-researched, especially in spontaneous pronunciation-unfocused tasks. In this study, we first investigated how task complexity influences L2 speech rhythm, and we then explored how L2 speech rhythm metrics might predict global pronunciation proficiency (comprehensibility and accentedness). Eighty-two Spanish/Catalan bilingual learners of English and a control group of eight native speakers (NSs) completed a simple and a complex version of an adapted monologic decision-making task. Oral production data were analysed using well-established rhythm metrics (%V, VarcoV, nPVI-V, and VarcoC), novel distance measures (Euclidean and Mahalanobis distance scores) and ratings from 13 English NSs. Results showed differential task complexity effects on L2 speech rhythm depending on the rhythm metrics and distance measures considered. Additionally, the %V rhythm metric and the Mahalanobis distance measure accounted for a modest amount of variance in both comprehensibility and accentedness scores, with Mahalanobis distances having a more reliable predicting power. The outcomes of this study point to the importance of further examining the role of task complexity in L2 speech rhythm in spontaneous speech and to what extent L2 speech rhythm is related to global measures of L2 pronunciation proficiency. These findings also highlight the need for identifying which rhythm metrics are more suitable to depict L2 speech elicited through different methods, particularly spontaneous speech.

The role of Interleukin-38 in modulating T cells in chronic Colitis: A mouse model study

BackgroundInterleukin (IL)-38 belongs to the IL-36 subfamily within the IL-1 family. Patients with inflammatory bowel diseases (IBD) exhibit higher levels of IL-38 in their intestinal tissue compared to healthy controls, suggesting that IL-38 may play a role in the pathogenesis of IBD. However, IL-38′s impact on T cell-mediated immune responses in gastrointestinal inflammation has not been investigated. Therefore, the objective of this work was to elucidate the role of IL-38 in modulating T cells in a mouse model of dextran sulfate sodium (DSS)-induced chronic colitis. MethodsRecombinant IL-38 (rIL-38) was administered intraperitoneally (i.p.) to mice with chronic colitis induced by DSS. Clinical symptoms, length of colon, and histologic alterations were assessed. Cytokine production was quantified using ELISA, and helper T (Th) cell subsets were evaluated via flow cytometry. ResultsAdministration of recombinant IL-38 (rIL-38) alleviated DSS-induced chronic colitis. In addition, animals with chronic colitis treated with rIL-38 exhibited a significant decrease in the spontaneous production of inflammatory cytokines by neutrophils in the lamina propria. Furthermore, rIL-38 treatment increased the absolute numbers and percentages of regulatory T cells (Tregs) but decreased the absolute numbers and percentages of Th1 and Th17 cells. Moreover, rIL-38 treatment also decreased IL-17A-producing γδT cells substantially. ConclusionThis study’s results show that IL-38 reduces the effects of chronic colitis caused by DSS by boosting Treg reactions and reducing Th1/Th17 reactions and IL-17A-producing γδT cells in LPL. Therefore, we propose that IL-38 has the potential to be utilized as a biological therapy agent for IBD.

Spontaneous Molecular Bromine Production in Sea-Salt Aerosols.

Bromine chemistry is responsible for the catalytic ozone destruction in the atmosphere. The heterogeneous reactions of sea-salt aerosols are the main abiotic sources of reactive bromine in the atmosphere. Here, we present a novel mechanism for the activation of bromide ions (Br-) by O2 and H2O in the absence of additional oxidants. The laboratory and theoretical calculation results demonstrated that under dark conditions, Br-, O2 and H3O+ could spontaneously generate Br and HO2 radicals through a proton-electron transfer process at the air-water interface and in the liquid phase. Our results also showed that light and acidity could significantly promote the activation of Br- and the production of Br2. The estimated gaseous Br2 production rate was up to 1.55×1010 molecules cm-2 ⋅ s-1 under light and acidic conditions; these results showed a significant contribution to the atmospheric reactive bromine budget. The reactive oxygen species (ROS) generated during Br- activation could promote the multiphase oxidation of SO2 to produce sulfuric acid, while the increase in acidity had a positive feedback effect on Br- activation. Our findings highlight the crucial role of the proton-electron transfer process in Br2 production; here, H3O+ facilitates the activation of Br- by O2, serves as a significant source of atmospheric reactive bromine and exerts a profound impact on the atmospheric oxidation capacity.

Spontaneous and Stimulated Production of Cytokines by Blood Cells Ex Vivo as a Biomarker of Initially High or Low Hypoxia Resistance in Rats.

Spontaneous and stimulated production of cytokines by peripheral blood cells obtained from the caudal vein of male Wistar rats was assessed before testing their resistance to oxygen deficiency in a decompression chamber. To study the spontaneous production of cytokines, heparinized blood cells were incubated in a culture medium (24 h, 5% CO2, 37°C) and the content of proinflammatory cytokines IL-6 and TNFα and anti-inflammatory IL-10 in the culture medium was assessed by ELISA. To stimulate cytokine production, blood cells were incubated for 24 h with LPS, phytohemagglutinin, and concanavalin A at final concentrations of 2, 4, and 4 μg, respectively. Two weeks after blood sampling, individual resistance of the animals to hypoxia in a decompression chamber was determined. In animals with low resistance to hypoxia, the levels of spontaneous production of all three cytokines were significantly higher, while after stimulation, the level of IL-1β increased by more than 2 times. The animals with spontaneous production of IL-10>50 pg/ml, IL-6>10 pg/ml, and TNFα>10 pg/ml, as well as with the increase in IL-1β production by more than 2 times upon stimulation were classified as low-resistant. At IL-10<15 pg/ml, IL-6<9 pg/ml, and TNFα<7 pg/ml, as well as the absence of the increase in IL-1β production upon stimulation, they were classified as high-resistant. The identified features of spontaneous and stimulated production of cytokines can be used as non-invasive biomarkers to determine the resistance to hypoxia without exposure to sublethal hypoxia in a decompression chamber.

ESP Needs Analysis of Macroskills of Social Work Students

This quantitative study employed needs analysis then revealed the preferred learning aids and learning activities, and the level of proficiency in reading, listening, writing, and speaking of 50 social work students in a private academic institution. Findings revealed that students showed a strong enthusiasm for visual and audiovisual aids as learning tools and lectures and class discussions as learning activities. Moreover, among the four macro skills, the students excel in reading comprehension at C1 level but face challenges in the affective domain; writing skills at B1 level, with strengths in content but struggles in organization; listening proficiency at B2 level, highlighting difficulties with accents and vocabulary; and speaking skills range from A2 to B1 levels, with stronger interaction skills at B2 level, indicating a need for improvement in fluency and coherence. These insights suggest that the social work students are capable of simple communicative English and are more inclined toward traditionalist and conceptual learning. Furthermore, students need more application activities that showcase their listening and speaking skills, as well as more contextualized and immersive learning activities and aids that incorporate variation and encourage spontaneous production.

Spontaneous Production of I2 at the Surface of Aqueous Iodide Solutions.

Several groups have recently reported spontaneous production of atmospherically reactive species, including molecular iodine (I2) at the air-water interface of droplets. In this study, glancing angle laser-induced fluorescence spectroscopy was used to track the luminol fluorescence at the surface of sodium iodide (NaI) and sodium chloride (NaCl) solutions. Although luminol fluorescence is hardly quenched by halide anions, even up to fairly high concentrations, it is effectively quenched by I2. We observe luminol fluorescence quenching at the surface of NaI solutions but not at the surface of NaCl solutions, pointing to the formation of I2 at the surface of NaI solutions. This provides further support for the proposal that the strong electric field or the reduction solvation present at the air-water interface can initiate spontaneous iodide activation and other chemistry there. The spontaneous production of I2 at the surface of aqueous iodide solutions presents a previously unconsidered source of iodine in the atmosphere.

SELF-ASSESSMENT METACOGNITIVE STRATEGIES IN A SPONTANEOUS ESL SPEECH PRODUCTION CONTEXT

Purpose – Self-assessment is regarded as a complex metacognitive process by scholars. Nevertheless, in the context of English as a Second Language (ESL) speaking, self-assessment practices often rely on assessment criteria and teacher commentaries. However, speaking involves spontaneous expression with limited access to external standards. Therefore, this case study aims to explore the metacognitive strategies that proficient ESL students use during selfassessment in spontaneous speech production contexts. Methodology – Three participants, purposefully selected, participated in two spontaneous group discussions recorded on video. Instances of participants’ dysfluency served as prompts in stimulated recall interviews, complemented by video recordings to validate participants’ responses. The thematic analysis of interview data utilised a conceptual framework integrating O’Malley and Chamot’s (1990) metacognitive strategies and Kormos’ (2006) speech production model. Findings – The analysis revealed that participants employed three key metacognitive strategies – organisational planning, selective attention, and self-monitoring to self-assess their spontaneous speech. Feedback sources, such as their proficiency in the second language (L2) and contextual factors, influenced the application and effectiveness of these strategies during self-assessment (SA). Significance – This study offers insights into how proficient ESL students self-assess their spontaneous speech production, leveraging their available resources. In addition, this study identifies speech challenges the participants encountered and how they applied metacognitive strategies to address them.

Impact of Skin Exposure to Benzo[a]pyrene in Rat Model: Insights into Epidermal Cell Function and Draining Lymph Node Cell Response.

The skin is a direct target of the air pollutant benzo[a]pyrene (BaP). While its carcinogenic qualities are well-studied, the immunotoxicity of BaP after dermal exposure is less understood. This study examines the immunomodulatory effects of a 10-day epicutaneous BaP application, in environmentally/occupationally relevant doses, by analyzing ex vivo skin immune response (skin explant, epidermal cells and draining lymph node/DLN cell activity), alongside the skin's reaction to sensitization with experimental hapten dinitrochlorobenzene (DNCB). The results show that BaP application disrupts the structure of the epidermal layer and promotes immune cell infiltration in the dermis. BaP exposure led to oxidative stress in epidermal cells, characterized by decreased reduced glutathione and increased AHR and Cyp1A1 expression. Production and gene expression of proinflammatory cytokines (TNF, IL-1β) by epidermal cells decreased, while IL-10 response increased. Decreased spontaneous production of IFN-γ and IL-17, along with unchanged IL-10, was observed in DLC cells, whereas ConA-stimulated production of these cytokines was elevated. Local immunosuppression caused by BaP application seems to reduce the skin's response to an additional stimulus, evidenced by decreased effector activity of DLN cells three days after sensitization with DNCB. These findings provide new insight into the immunomodulatory effects and health risks associated with skin exposure to BaP.