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Neurosurgery is a demanding specialty, and a trainee’s exposure to its tenets is usually achieved through residency. Medical students only access neurosurgical knowledge via brief stints in clerkships/electives and often lack mentorship and early exposure. This study sought to investigate the varying expectations about neurosurgical training held by Canadian medical students, with the goal of determining the impact of early exposure through educational opportunities and mentorship in developing interest and familiarity in the field.
Methods:
A cross-sectional study across Canada was conducted where students were provided with a 35-point questionnaire pertaining to mentorship, educational opportunities and interests regarding neurosurgery through REDcap. Questions were open-ended, closed-ended (single choice) or five-point Likert scale (matrix format). Interest in pursuing neurosurgery was selected as the primary outcome of this study and was dichotomized into high or low interest. Predictors of interest were determined using multivariable logistic regressions.
Results:
A total of 136 students from 14 accredited Canadian medical schools responded to the study. Most (55.9%) had prior exposure, and the most commonly reported deterring factors were work–life balance (94.5%) and family (84.6%). Predictors of interest included participation in relevant case-based discussion (OR = 2.644, 95% CI [1.221–5.847], p = 0.015) and involvement in neurosurgical research encouraged by home institution (OR = 1.619, 95% CI [1.124–2.396], p = 0.012).
Discussion
Future efforts to improve student interest should focus on early exposure to the field such as developing pre-clerkship neurosurgical electives or medical student groups focused on neurosurgery.
The Leidenfrost effect occurs when drops are deposited on a highly superheated solid surface, creating a thin vapour film through rapid evaporation that levitates the drops. For drop with a radius exceeding a critical value, a vapour bubble forms and bursts from its bottom centre, a phenomenon known as chimney instability. Despite extensive investigation, the impact of Leidenfrost drop’s rotation on its chimney instability has remained unexplored. This study addresses this gap by providing both numerical and approximate solutions to the theoretical models. We identify two distinct regimes where either gravitational force or centrifugal force is the primary driver of chimney instability. These regimes are characterised by a non-dimensional rotation number, Ro, which represents the ratio between centrifugal force and gravitational force. Our findings reveal clear scaling laws that relate the critical geometrical parameters (radius, volume and height of the drop) for chimney instability to Ro, demonstrating that rotation can induce chimney instability in smaller drops. The scaling laws are elucidated through pressure perturbation analyses under a virtual perturbation to the drop profile at the critical state for chimney instability. Additionally, by varying the evaporation number $Ev$, we demonstrate that while increased superheat reduces the critical radius in the absence of rotation, the scaling laws related to Ro for a rotating drop remain unaffected. Building on these insights, we present a master curve in a simplified form that accurately predicts the critical state for chimney instability under various angular velocities, gravitational accelerations and superheat conditions.
The Kahramanmaras Earthquakes (2023) are the largest and most devastating earthquakes in the history of the Republic. The effects of these earthquakes are particularly deeply felt among younger generations and trigger various psychological factors. Therefore, the aim of this study is to measure the levels of post-traumatic stress disorder (PTSD), social phobia (SP), generalized anxiety disorder (GAD), and depression on separation anxiety disorder (SAD) among adolescent earthquake survivors affected by the Kahramanmaras Earthquakes (2023).
Methods
In the study, the data were obtained using a survey method. A total of 605 adolescent earthquake survivors exposed to the Kahramanmaras earthquakes were reached. The research was analyzed using structural equation modeling (SEM).
Results
Surprisingly, according to the research findings, there was no significant and positive relationship between SP (β = −0.006, P > 0.05) and Depression (β = −0.117, P > 0.05) on SAD.
Conclusions
Consequently, while PTSD and GAD had significant and positive effects on SAD in those adolescent earthquake survivors affected by the Kahramanmaras Earthquakes (2023), SP and Depression did not have significant and positive effects on SAD. Therefore, it is recommended that future studies examine the effects of SP and Depression on SAD more comprehensively and in detail through qualitative research.
The existing studies on vortex rings have concentrated on non-zero circulation. However, the cases of zero circulation may also be significantly noteworthy on both theoretical and practical grounds. As the first attempt on this subject, in this paper a family of viscous laminar vortex rings with zero circulation and a moderate ratio of core radius to ring radius is studied using numerical simulations of the incompressible Navier–Stokes equations. This unusual zero circulation is achieved by assigning a special layered vorticity distribution with alternate signs to the vortex core. At the initial moment, the ring is axisymmetric, swirl-free and of a circular cross-section. It is found that the axial symmetry and the non-swirl nature of the vortex ring are preserved during the evolution, and the vortex ring endures a transition from the initial layered structure to a shell structure, then degenerates to an ordinary vortex ring with non-zero circulation at last. Significant vorticity cancellation is observed due to the interactions among the layered structures. A new Reynolds number, based on the absolute value of vorticity, is applied to the zero-circulation vortex rings in the present work. For such vortex rings, cases of both zero and non-zero vortical impulse can happen, unlike the ordinary ones with only non-zero vortical impulse. Additionally, it is found that the vortical impulse can be irrelevant to the ring diameter. The study may shed light on modelling certain real flows characterised by distinct vortex structures or configurations.
The central Maya lowlands (CML) display an uncommon demographic history—the absence of a millennial population rebound from its former occupational peak, about 800 CE. Here we postulate why the loss of a well-populated CML during the Late Classic-Terminal Classic periods failed to regain substantial occupation during the subsequent 700-800 years before the Spanish conquest of the Maya realm. Updating the narrative of stressful human-environmental conditions, shifts in trade routes, and long-term paucity of occupation in the CML, we examine push-pull factors that affected Postclassic Maya population geography. These factors include population pressures, environmental hazards, resource conditions, and livelihood standards that existed in the Postclassic Period between northern and coastal lowlands and the CML. The advantages that the CML maintained before Postclassic times, foremost regaining superior environmental conditions for agriculture, were insufficient pull factors given the low levels of push factors in the northern and coastal lowlands. We draw attention to the under-treated problem—the failure of a population rebound in the CML—and encourage improvements in systematic data and analytics to address it, including consideration of non-material, socio-cultural factors.
English employs a variety of comparative formation strategies. Theoretical and corpus-based research has established that their distribution depends on a variety of factors. In this article, we take an experimental approach to test analytic, synthetic and double comparative forms in relation to register in American and British English. We report on a rating study investigating the appropriateness and interpretation in terms of evaluativity of the three comparative forms. Our findings confirm the hypothesis that the comparative variants are not considered equally appropriate, but the effect is not as strong as would be expected under the hypothesis that frequency of occurrence is directly related to linguistic judgments. The analytic and double comparative alternatives exhibit lower appropriateness levels than the synthetic comparative. Analytic and double comparative forms are rated as less appropriate in formal than in informal contexts, which did not show an effect on the synthetic form. Furthermore, the analytic variant shows a different behavior in terms of the interpretation than the other forms in that a stronger effect of evaluativity is detected. Limitations and future directions are discussed. Our study is the first to provide experimental evidence for certain hypotheses emerging from corpus-based research.
The experimentally backed and hitherto overlooked empirical observation of the paper is a contrast among indefinite Positive Polarity Items regarding their possibility of being rescued under certain operators with different rescuing potential. If/surprise/only/don’t think can rescue some-indefinites, suspending their anti-licensing (i.e., their impossibility to occur in the scope of a clausemate negation): while some-pronouns (in English and French) and des-indefinites in French exhibit the expected rescuability, English some-NPs remain unexpectedly degraded. Our account relies on the hypothesis that ‘rescuing’ is due to sentential negation being interpreted as ‘external’ (vs. nullified as in most literature). The definition we propose for external negation is syntactic: rescuing operators allow sentential negation to raise to an illocutionary functional projection above Tense Phrase (TP). Thus at LF (Logical Form), the negation takes that higher projection (rather than TP) as complement and becomes harmless for some-indefinites. The semantic correlate of this syntactic proposal is the interpretation of external negation as a propositional operator. As it involves the illocutionary periphery, rescuing is pragmatic in nature. The different rescuing potential between some-pronouns and some-NPs arises from the interplay between their distinct LF-representations and a minimal-event pragmatic constraint on rescuing.
Outbreaks of Rachiplusia nu have occurred on soybean in Brazil as the first species resistant to the Bt soybean expressing only Cry1Ac protein, triggering a significant increase in insecticide use on the crop. This threatens one of the most important benefits of adopting Bt soybean cultivars – the reduction of chemicals. Therefore, this research studied the biology and parasitism capacity of Trichogramma pretiosum at 20, 25, and 30 ± 2 °C on R. nu eggs in order to evaluate the potential of releasing this egg parasitoid in soybean to manage R. nu. Parasitoid exhibited high biological performance on the R. nu eggs as observed in the lifetime parasitism of 24.9, 46.4, and 34.4 R. nu eggs at 20, 25, and 30 °C, respectively, and 100% emergence in both biology and parasitism capacity experiments. The sex ratio was statistically lower at 20 °C (0.4947), but at all studied temperatures, the production of female descendants was equal (sex ratio of 0.4947 at 20 °C) or higher (sex ratio of 0.6666 at 25 °C and 0.6524 at 30 °C). All other evaluated parameters were similar to previously positive recorded observations for T. pretiosum on other soybean pests, such as Anticarsia gemmatalis and Chrysodeixis includens, against which the parasitoid has already been commercially released in the fields as a biocontrol option. Therefore, T. pretiosum might also be released in soybean as an egg parasitoid against R. nu, what needs to be confirmed in future field trials.
The Resilience Hub was established to coordinate mental health and psychosocial support for anyone affected by the 2017 Manchester Arena terrorist attack.
Aims
To use the Hub’s mental health screening data to examine the variation in symptoms reported by children and young persons (CYP) and their parent/guardian and explore any association with time delay in post-event registration or parental distress.
Method
CYP engaging with Hub services were separated into eight ‘admission’ groups depending on when they registered post-incident. CYP were screened for trauma, depression, and generalised and separation anxiety. Parents/guardians also completed screening measures for their own and their child’s anxiety. Baseline and follow-up scores were compared between admission groups. Parental and CYP assessments of the CYP’s anxiety score was compared with the measure of parental distress.
Results
Almost half of CYP registered in the first 3 months of service launch, with numbers of new registrations falling during each subsequent screening cycle. Generally, there was an increase in baseline screening scores as Hub registration time increased. The Children’s Impact of Event scale score decreased by 0.11 (95% CI: −0.17, −0.05) per month, but the score for depression increased by 0.06 (95% CI: 0.03, 0.10). Longitudinal patterns in anxiety and separation were difficult to discern. Screening scores of CYP registering later reduced at a faster rate than those of the first registrants. Higher levels of parental mental distress were correlated with increased anxiety scores assigned to the CYP in relation to the anxiety score reported by the CYP themselves.
Conclusion
CYP who registered earlier were less symptomatic, although those registering later did show increased improvement in their symptoms, indicating that the Hub was beneficial. Parental well-being was associated with child mental distress, indicating that shared family trauma should be considered when planning care.
The silent patent ductus arteriosus is currently considered a benign lesion with some practitioners dismissing these patients from cardiac follow-up. We present a 5-year-old male with no known cardiac history who presented with endarteritis in a silent patent ductus arteriosus and underwent successful antibiotic treatment and transcatheter device occlusion.
This article examines the place of colonial Jews and Judaism in the Protestant imagination through the history of Hebrew printing in early America. While scholarship in Christian Hebraism has emphasized points of commonality and interreligious dialogue through shared texts between Judaism and Christianity, this study explores treatments of Hebrew that foreclosed collaboration and conversation between the two groups. The essay offers the term “Protestant Hebrew” to describe how colonial Anglo-American Protestants performed Hebrew to support ministerial authority and to imagine a receptive English-speaking captive Jewish audience for their works. In contrast, diasporic Sephardic Jews treated Hebrew as a necessary instrument for sustaining identity and communication networks across the Atlantic. This disparity was most evident through the publishing culture around Hebrew text types. Colonial printing presses carried just enough Hebrew type for Protestant productions to occasionally adorn their text with Hebrew characters, but never enough to treat it as its own language. Limited types would become a point of frustration for Jewish and Protestant authors who had to rely on printers overseas or on manuscript circulation to publish in Hebrew to a wider audience. Protestant Hebrew demonstrates how the constraints of Anglo-Protestant culture could materialize through the very mechanisms of colonial publishing.
For American archaeology, ceramic styles have historically played a key role in assigning different regional and temporal cultural traditions. San Francisco is one of the earliest pottery styles in northwestern Argentina (NOA; 2000-1500 BP) and has been considered a chronological marker, as it laid the foundation for the development of other ceramic traditions in the NOA region during the Formative period. It is characterized by polished incised gray pieces, bichrome designs, and zooanthropomorphic or anthropomorphic pipes. Regarding the discovery of San Francisco pottery beyond what is considered its core area—the valley of the same name in the eastern part of Jujuy Province—various interpretations have been proposed over the past three decades. These range from the effective occupation of new territories to the exchange, circulation, or imitation of vessels. Based on the composition of ceramic pastes, this research suggests the existence of specific recipes, allowing for the identification of potential local productions and testing hypotheses about the circulation or non local production of San Francisco pottery. Furthermore, the frequent incorporation of grog (chamote) into the fabric is highlighted, reflecting a cohesive manufacturing tradition that persisted over the centuries.