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A large body of literature has examined perceptual training, especially using the high variability phonetic training (HVPT) technique, where multiple talkers are included in the training set to help learners develop more accurate additional (second) language (L2) speech sound categories. Yet, most experimental studies focus on relatively short-term gains using a pre-post–delayed design, providing limited insight into longer-term training effects and how the timing of training might regulate its effectiveness. To begin addressing this gap, we implemented HVPT at two contextually relevant windows of opportunity during a university study program. Thirty-six first (native) language Spanish students participated in this study. Students were randomly assigned to two groups. One group (G1) received training at the beginning of their study program, which coincided with the onset of intensive L2 exposure; the second group (G2) received training in the second year, while enrolled in an English phonetics and phonology course. Both groups completed four HVPT sessions (identification tasks) focusing on a set of challenging L2 English vowels (/iː ɪ æ ʌ ɜː e ɒ ɔː/). Perception was measured at four testing times (in years 1 and 2, before and after HVPT) with identification tasks. The results showed that HVPT had a positive impact regardless of the timing of its implementation. However, students also improved outside of training, which suggests that intensive language study can facilitate some perceptual learning.
Functional neurological disorder (FND) is a well-recognised condition often involving a complex interplay of biopsychosocial factors. Although awareness of FND among the general population and clinical staff has increased and improved over recent years, challenges remain for the sufferers across multiple areas. This reflective piece explores these challenges using a relational understanding. The model of cognitive analytic therapy (CAT) is used to examine some of the dynamics and concepts at play in FND.
The Ross procedure offers several advantages for adolescents requiring aortic valve replacement, but progressive pulmonary autograft dilation is a well-described risk. To provide novel insight into the pre-Ross histology in an adolescent with bicuspid aortic valve (BAV)-associated aortopathy, we describe the extracellular architecture of the pulmonary artery (PA) compared to the native ascending aorta.
Methods:
A 15-year-old with BAV, symptomatic moderate aortic insufficiency and aortic stenosis, and ascending aortic dilation underwent Ross. Intraoperative specimens included the main PA and ascending aorta. Tissue specimens were fixed, stained using 1) haematoxylin and eosin, 2) Verhoeff’s van Gieson, and 3) trichrome, and compared using light microscopy.
Results:
Elastin van Gieson stain revealed that the aortic media in the dilated ascending aorta contained a greater concentration of dense elastin weaves and a regular distribution of collagen compared to the PA. In contrast to the dense and organised compaction of elastic fibres in the media of the aortic specimen, the PA, though grossly normal, demonstrated extensive disruption and fragmentation. Trichrome staining revealed minimal fibrosis in both specimens.
Conclusions:
Notable pre-Ross histological differences include marked disruption of elastin in the PA compared to the aorta. Age-based differences in Ross outcomes suggest that adolescents may experience proportionally more significant autograft dilation over time, so future studies should include prospective collection and histological analysis of specimens across the age spectrum, both pre- and post-Ross, to allow comparison to age-matched controls.
Halloysite nanotubes (HNTs) face significant challenges in their application due to their aggregation, poor dispersion and high hydrophilicity, which limit their integration into polymer matrices. This study introduces a novel functionalization strategy for Algerian HNTs, targeting their inner and outer surfaces with triethoxy(octyl)silane (OTES) for silanization and caffeic acid (CA) for lumen loading. Comprehensive characterization techniques were used to analyse pristine and OTES-modified HNTs (O-HNTs) and CA-loaded HNTs (CA-HNTs) to evaluate the impacts of both selective agents, which successfully altered the structural, textural, chemical, morphological and thermal HNTs properties. The crystalline structure and changes in crystallite size following surface modification were determined using X-ray diffraction analysis. Brunauer–Emmett–Teller analysis showed that the surface area of O-HNTs increased to 74 m2 g–1 compared to 54 m2 g–1 for HNTs, whereas CA-HNTs experienced a surface area decrease to 42 m2 g–1 owing to pore obstruction, with the pore sizes shifting to 10–12 nm for O-HNTs and to 16 nm for CA-HNTs. Fourier-transform infrared spectroscopy and X-ray fluorescence confirmed effective surface modification through the achievement of successful chemical bonding and a shift in the elemental composition. Morphological analysis using scanning electron microscopy revealed considerable morphological changes in both treatments, and thermogravimetric analysis demonstrated that the thermal stability of HNTs modified with CA was improved, with a higher decomposition peak at 520°C. These modifications effectively improved the dispersion, thermal stability and compatibility of the HNTs, highlighting the potential of the modified Algerian HNTs as promising green nanofillers in polymer nanocomposite applications, such as active packaging and thermal insulation coatings.
This study presents a numerical investigation of wall-mounted tandem flexible plates with unequal lengths in a laminar boundary layer flow, examining both two-dimensional (2-D) and three-dimensional (3-D) configurations. Key parameters influencing the system include the plate’s bending stiffness ($K$), Reynolds number (${Re}$) and length ratio ($L^*$). Five motion modes are identified: dual collapse (DC), flapping collapse (FC), dual flapping (DF), static flapping (SF) and dual static (DS). A phase diagram in the ($K,L^*$) space is constructed to illustrate their regimes. We focus on DF and SF modes, which significantly amplify oscillations in the downstream plate – critical for energy harvesting. These amplification mechanisms are classified into externally driven and self-induced modes, with the self-induced mechanism, which maximises the downstream plate’s amplitude, being the main focus of our study. A rigid–flexible (RF) configuration is introduced by setting the upstream plate as rigid, showing enhanced performance at high ${Re}$, with oscillation amplitudes up to 100 % larger than the isolated flexible (IF) plate configuration. A relation is developed to explain these results, relating oscillation amplitude to trailing-edge velocity, oscillation frequency and chord length. Force analysis reveals that the RF configuration outperforms both IF and flexible–flexible (FF) configurations. Unlike frequency lock-in, the RF configuration exhibits frequency unlocking, following a $-2/3$ scaling law between the Strouhal number ($St$) and ${Re}$. Results from the 3-D RF configuration confirm that the 2-D model remains applicable, with the self-induced amplification mechanism persisting in 3-D scenarios. These findings enhance understanding of fluid–structure interactions, and offer valuable insights for designing efficient energy harvesting systems.
Human computers and micro-observers were scientific workers who performed calculations or reduced and analysed data before the advent of electronic computers. They were a staple of big science during the 19th and early to mid 20th century. Despite their prevalence within big science their epistemic roles remain unexamined by philosophy of science. This paper investigates the epistemic roles of the human computers at the Harvard College Observatory 1880-1920 and of micro-observers at the Bristol Nuclear Research Group 1935-1955. This paper argues that the instrumentalisation of human computers and micro-observers has negative epistemic consequences for the methodology of science.
Previous studies investigating the association between pubertal timing and depression in girls primarily use self-reported age at menarche (AAM). This study examines a range of pubertal timing indicators, including anthropometric and self-reported measures.
Aims
Compare associations of multiple indicators of pubertal timing with depressive symptoms and depression in girls and explore whether these associations persist into early adulthood.
Method
The sample comprised 4607 girls from UK-based Avon Longitudinal Study of Parents and Children. Seven measures of pubertal timing were assessed between ages 7 and 17 (age at: peak height velocity (aPHV); peak weight velocity; peak bone mineral content velocity; Tanner pubic hair and breast development stage 3; axillary hair; and AAM). Depressive symptoms were measured at 14, 17, 18 and 24 years using the Short Mood and Feelings Questionnaire. Depression was assessed at 15, 18 and 24 years using the Development and Well-Being Assessment and Clinical Interview Schedule-Revised. Multivariable logistic regression models were adjusted for socioeconomic status and pre-pubertal body mass index.
Results
Later pubertal timing was associated with lower odds of depressive symptoms at age 14 across six measures, including aPHV (adjusted odds ratio (AOR): 0.82; 95% CI 0.72, 0.95) and AAM (AOR: 0.84; 95% CI 0.76, 0.92). Later AAM and Tanner breast stage 3 were associated with lower odds of depression at age 18 (AOR: 0.85; 95% CI 0.75, 0.97 and AOR: 0.83; 95% CI 0.72, 0.95, respectively). Associations attenuated by age 24.
Conclusions
Later pubertal timing was associated with reduced odds of depressive symptoms during mid-adolescence, with associations attenuating by adulthood.
This article examines the reasons for the widespread use of sea loans in financing Spain’s transatlantic commerce before the 1780s, and for their subsequent decline. Although never in the hands of a company with monopoly rights, Spain’s colonial trade was heavily regulated before 1778. The system reduced market risk and unpredictability by operating through a single Spanish port, keeping the colonies undersupplied, and lowering the frequency of the exchanges to allow for silver accumulation in Spanish America. This afforded significant, though volatile, profit margins. Such conditions fostered the use of the sea loan because the instrument enabled the lender to reap greater returns by charging higher-than-standard interest rates while avoiding usury laws. In contrast, the 1778 free-trade regulations increased competition and unpredictability, narrowing profit margins. Trade expanded, and “marine interest” rates dropped, precipitating the end of the sea loan as the hallmark credit instrument of the Spanish colonial trade.
Employee perceptions of organizational politics are mostly negative and lead to negative consequences. Social capital is an intangible asset based on social relationships; in organizations it can be either personal or intra-organizational. This study aims to determine whether employees who perceive their workplace as political can benefit from social capital and how doing so affects their performance. A qualitative pilot study refined variables and hypotheses, and two rounds of quantitative surveys were subsequently conducted 4 months apart, with 907 and 762 participants. The analysis demonstrated that intra-organizational social capital mediated the connection between personal social capital and employee performance and moderated the relationship between perceived organizational politics and employee performance, hence mitigating the negative effect of perceived organizational politics. Consequently, according to the Job Demands–Resources (JD-R) theory, intra-organizational social capital serves as a job resource that can reduce the aversion effect of perceived organizational politics as a job demand.
The aim of this study was to evaluate the relative validity of food and nutrient intakes estimated by a brief-type diet history questionnaire for Japanese children and adolescents (BDHQ15y) designed to assess habitual dietary intake during the previous month. A total of 432 boys and 412 girls aged 6–17 years from thirty-two prefectures in Japan completed the BDHQ15y and subsequently provided 8-day weighed dietary records (DR) on two non-consecutive days over four seasons for comparison. Among the intakes of forty-four nutrients and thirty-one food groups adjusted for energy intake using the density model, the BDHQ15y showed percentage differences in median intake of less than 10 % compared with the DR for nineteen nutrients in both sexes, as well as for eleven and seven food groups in boys and girls, respectively, indicating good agreement for key nutrients and food groups, including protein, fat, carbohydrate, dietary fibre, grains, vegetables, dairy products and sugar-sweetened beverages (SSB). The median values (25th–75th percentiles) of Spearman’s correlation coefficients in boys and girls were 0·33 (0·28–0·38) and 0·28 (0·23–0·35) for nutrients, respectively, and 0·36 (0·29–0·42) and 0·29 (0·24–0·36) for food groups, respectively. Bland–Altman plots showed wide limits of agreement, with overestimation at higher intakes for most nutrients and food groups, except SSB. In conclusion, the BDHQ15y shows promise for large-scale dietary monitoring, particularly for estimating group-level intakes of key nutrients and food groups. However, its limited ability to rank individual intakes and the variability in individual-level assessments necessitate cautious interpretation and application.
Drought, salt and low-temperature stress significantly reduce the germination rate of cotton seeds. Additionally, the seed composition of seeds, including protein, oil and gossypol, are also closely linked to germination performance. This study assessed the seed composition of 120 cotton genotypes and their ability to germinate under drought, salt, and low-temperature stress, and compared with under standard conditions (control). Stress resistance during the germination stage was comprehensively evaluated using principal component analysis (PCA), which categorized the genotypes into three groups: 35 high-stress tolerance, 74 medium-stress tolerance and 11 medium sensitivity. Subordinate function analysis revealed that the comprehensive resistance D values of the 120 genotypes ranged from 0.20 to 1.12. Correlation analysis showed a significant negative correlation between seed oil content and germination under drought and salt stress (R = −0.27** and R = −0.24**). Additionally, germination under drought and salt stress were positively correlated (R = 0.58***). SNP_A07_90682411-based Kompetitive Allele-Specific PCR (KASP) markers identified that AA-type genotypes had significantly higher D values for comprehensive stress tolerance, drought resistance and salt resistance at the germination stage compared to GG-type genotypes (P = 0.0003, P = 0.010, and P = 0.0004, respectively). This study identified highly resistant and sensitive genotypes to various abiotic stresses, during germination and demonstrated that the ability of the newly developed KASP molecular markers effectively differentiate comprehensive germination performance under stress. These findings provide valuable references for understanding stress tolerance mechanisms during germination and breeding stress-tolerant cotton varieties.
Spine simulators offer learners risk-free environments to develop psychomotor skills for pedicle screw insertions. The virtual reality TSYM simulator deconstructs and simulates pedicle screw insertions. This case series study investigates face, content, construct, and convergent validity of an L4–L5 bilateral pedicle screw insertion on the TSYM simulator.
Methods:
Neurosurgical-orthopedic residents, fellows, and spine surgeons performed an L4–L5 bilateral pedicle screw insertion on the TSYM simulator. Participants were classified a priori into skilled (postgraduate year (PGY) 5–6, fellows, and consultant neurosurgeons or orthopedic surgeons) or less skilled (PGY 1–4) groups. Face and content validity were assessed utilizing a 7-point Likert scale. Construct validity was determined by investigating group differences in simulation-derived performance metrics and the Objective Structured Assessment of Technical Skills (OSATS) ratings. Convergent validity was examined by correlating simulation-derived performance metrics and OSATS ratings.
Results:
Thirteen skilled and 14 less skilled participants were included in this study. Eight of nine face and content validity statements were rated a median ≥ 4. Significant differences between the groups were found for four simulation-derived performance metrics (P < 0.05) and all OSATS categories (P < 0.001). Three simulation-derived performance metrics (maximum force and tool contact using the simulated screwdriver and three-dimensional velocity using the tap) significantly correlated with OSATS ratings.
Conclusion:
The L4–L5 bilateral pedicle screw insertion simulation on the TSYM platform demonstrated mixed and variable evidence for face, content, construct and convergent validity, supporting its educational potential for spine surgery training, but improvements are needed to optimize learning.
Anhedonia is a common and impairing symptom of psychopathology that predicts negative outcomes and may undermine peer relationships. Anhedonia comprises both trait (stable, time-invariant) and state (dynamic, time-varying) components. Relative to trait anhedonia, state anhedonia may be more strongly related to proximal risk for deleterious outcomes. Yet, associations between state anhedonia and daily-life socio-affective experiences in adolescence are not well understood. Thus, the present study used ecological momentary assessment (EMA) to examine within-person associations between state anhedonia and the quantity and quality of daily-life peer interactions among a sample of adolescents enriched for suicidality risk, a population at high risk for anhedonic and peer problems. Participants included 102 adolescents assigned female at birth (ages 12–18; M[SD] = 15.34[1.50]; 67.6% at elevated risk for suicidality). State anhedonia, as well as being with peers, connectedness with peers, and positive affect with peers, was measured three times per day for 10 days via EMA (n = 30 prompts). Multilevel models demonstrated that within-person fluctuations in state anhedonia relate to reduced odds of being with peers, as well as decreased connectedness and positive affect with peers. Findings suggest that dynamic changes in state anhedonia are related to both the quantity and quality of peer experiences among adolescents.
This paper examines whether the democratic shortcomings of Restoration Spain influenced the expansion of education spending. Specifically, we discuss how electoral outcomes conditioned the allocation of primary education investment across provinces from 1902 to 1922. Our results show that voting for minority parties and the extensive political patronage at the provincial level hindered public primary schooling outlays. We argue that the government punished “rebellious” provinces to preserve the regime, and that education was not well suited to support patron–client relationships. We also show that these effects diminished after World War I, as government control over electoral outcomes declined. Accordingly, by the end of the period, political voice gained a more salient role.
In what sense can human beings be conceived of as social beings? I argue that sociality is not merely an attribute of the species to which we belong; rather, the way in which we belong to our own life-form is itself socially mediated. To bring this other sense of sociality into view, the article (I) distinguishes the logical sociality of all living beings from the material sociality of social animals and the political sociality of self-conscious social animals. (II) The political sociality characterizing human beings requires a complex second-personal articulation through which alone we can exist as members of our life-form and determine its content. (III) Constituted in this way, the human form of life is characterized by a particularly open and at the same time precarious character. (IV) Against this background, forms of objective spirit are necessary which grant us a generalized recognition and relieve us from the contingency of particular second-personal recognitions, without abandoning the openness of the sociality of the human form of life. This double requirement has led to paradoxical institutions in modern society which strive to protect and ensure the sociality of the human form of life precisely by naturalizing and individualizing our access to it.
The oldest civilisation on the face of the Earth can be traced to India, home to the largest democracy of our times. Fast forward five millenia, a young nation at 78 places the aortic cross clamp most of others on a per diem basis. Somewhere in between, Donald Nixon Ross, who has been interred in this great Hall of Fame [1] opined that “it is rare to know of surgeons who can perform an operation better and often, seamless than its namesake, and among the few there are, Sampath Kumar is one”. It gives us great pleasure to introduce at the time of his induction in the Paediatric Cardiology Hall of Fame, one of finest humans our profession is privileged to have – Professor Arkalgud Sampath Kumar. Kumar has earned the peerage accorded to few surgeons in our milieu for his lifelong commitment to patientcare, teaching, research and innovation – making him the definition of a quadruple threat in academic surgery. Coming from Professor Anderson, we deem it an honor to present this character-sketch of this gentleman surgeon and mentor, who has the rare distinction of expanding the horizons of paediatric cardiovascular surgical care in the public, private and philanthropic institutions, among others through this encomium.
The ability of news media to report on events and opinions that are critical of the executive branch of government is central to media freedom and a marker of meaningful democratization. Existing indices use scoring criteria or expert surveys to develop country year measures of media criticism. In this article, we introduce a computationally inexpensive and fully open-source method for estimating media criticism from news articles using à la carte (ALC) word embeddings. We validate our approach using Arabic-language news media published during the Arab Spring. An applied example demonstrates how our technique generates credible estimates of changes in media criticism after a democratic transition is ended by a military coup. Experiments demonstrate the method works even with sparse data. Analyses of synthetic news media demonstrate that the method extends to multiple languages. Our approach points to new possibilities in the monitoring of media freedom within authoritarian and democratizing settings.
Most outbreaks associated with contaminated antiseptics and disinfectants had been attributed to user errors, as identified in our previous review in 2007. Although numerous regulations and guidelines have been established for proper use of antiseptics and disinfectants since then, such outbreaks continue to occur. To address this issue, we conducted a literature review of outbreaks and pseudo-outbreaks linked to contaminated antiseptics and disinfectants, aiming to update the outbreak characteristics and propose new prevention strategies.
Methods:
We searched the published literature from 2006 to 2024 via the PubMed database.
Results:
Among 2,307 publications identified, twenty-one outbreaks and 4 pseudo-outbreaks were reviewed. Among the outbreaks, seventeen (81%) were linked to antiseptics including chlorhexidine or low-level disinfectants including quaternary ammonium compounds. A median of 12 individuals (range: 3–256) developed infections, including ventilator-associated pneumonia, skin and soft tissue infections, or catheter-related infections, resulting from direct use of contaminated mouthwashes and skin antiseptics on patients, leading to 55 fatalities. Thirteen (62%) outbreaks were attributed to intrinsically contaminated products, which led to product recall and regulatory changes. Seven (33%) were linked to extrinsically contaminated antiseptics or disinfectants, all associated with improper practices in preparation and storage. Control measures included use of sterile water for preparation, disinfection or replacement of dispensers and containers, and prohibition of using solutions prepared in the hospital laboratory.
Conclusions:
To avoid outbreaks associated with contaminated antiseptics and disinfectants, healthcare personnel should understand the risks of contaminated antiseptics and disinfectants, and prevention strategies to avoid extrinsic contamination.