Mechanisms accounting for gendered differences in mental health status among young Canadians: A novel quantitative analysis.

Adolescent girls consistently report worse mental health than boys. This study used reports from a 2018 national health promotion survey (n = 11,373) to quantitatively explore why such gender-based differences exist among young Canadians. Using mediation analyses and contemporary social theory, we explored mechanisms that may explain differences in mental health between adolescents who identify as boys versus girls. The potential mediators tested were social supports within family and friends, engagement in addictive social media use, and overt risk-taking. Analyses were performed with the full sample and in specific high-risk groups, such as adolescents who report lower family affluence. Higher levels of addictive social media use and lower perceived levels of family support among girls mediated a significant proportion of the difference between boys and girls for each of the three mental health outcomes (depressive symptoms, frequent health complaints, and diagnosis of mental illness). Observed mediation effects were similar in high-risk subgroups; however, among those with low affluence, effects of family support were somewhat more pronounced. Study findings point to deeper, root causes of gender-based mental health inequalities that emerge during childhood. Interventions designed to reduce girls' addictive social media use or increase their perceived family support, to be more in line with their male peers, could help to reduce differences in mental health between boys and girls. Contemporary focus on social media use and social supports among girls, especially those with low affluence, warrant study as the basis for public health and clinical interventions.

Domains of spirituality and their importance to the health of 75 533 adolescents in 12 countries.

Spirituality is an ancient concept with many contemporary applications to the field of health promotion. While recognized in the UN Convention on the Rights of the Child as a basic human right, definitional misunderstandings about what spirituality is, and is not, and the mechanisms by which it affects the health of young people, remain. In this cross-national analysis involving >75 000 adolescents from 12 countries, we examined the relative importance of each of four spiritual health domains (connections to self, others, nature and the transcendent) in the lives of young people, and how these connections relate to a standard indicator of positive mental health status. Descriptive and applied regression analyses confirmed two major findings: (i) boys and girls in all 12 countries ranked the importance of each of the four domains in the same order, with 'connections to self' identified as most important; and (ii) both direct and indirect pathways are evident that connect the remaining three domains to positive mental health status, but through strong connections to self. Based on our scale items, fostering a strong connection to self, which involves cultivating a sense of meaning, purpose and joy in the lives of adolescents, appears most fundamental to fostering optimal mental health. This may be achieved directly or, dependent upon context and culture, indirectly with emphasis on the connections afforded by the other three domains. Such findings provide important insights to guide the content of adolescent health promotion interventions.

Spirituality is considered by many to be an important domain of health. It is sometimes measured in four domains of connections: to oneself, to others, to nature and to the transcendent. While the importance of such connections is recognized as a fundamental human right for children, few international studies have studied their impacts on the health and well-being of young people. In this study of young people conducted over 4 years in 12 countries, we examined the perceived importance of each of four spiritual health domains and how they each related to positive mental health status in >75 000 adolescents. 'Connections to self' were consistently viewed as most important among boys and girls in all 12 countries. Fostering of strong connections to self, which involves cultivating a sense of meaning, purpose and joy in the lives of adolescents, appears most fundamental to achieving mental health and well-being. This may be achieved directly through a focus on connections to self, or indirectly by focusing on the indirect effects of the other three domains on mental health. This opens up many opportunities for health promotion in child populations, internationally.

Single Nodal Loop of Accidental Degeneracies in Minimal Symmetry: Triclinic CaAs_{3}.

The existence of closed loops of degeneracies in crystals has been intimately connected with associated crystal symmetries, raising the following question: What is the minimum symmetry required for topological character, and can one find an example? Triclinic CaAs_{3}, in the space group P1[over ¯] with only a center of inversion, has been found to display, without need for tuning, a nodal loop of accidental degeneracies with topological character, centered on one face of the Brillouin zone that is otherwise fully gapped. The small loop is very flat in energy, yet is cut four times by the Fermi energy, a condition that results in an intricate repeated touching of inversion related pairs of Fermi surfaces at Weyl points. Spin-orbit coupling lifts the fourfold degeneracy along the loop, leaving trivial Kramers pairs. With its single nodal loop that emerges without protection from any point group symmetry, CaAs_{3} represents the primal "hydrogen atom" of nodal loop systems.

Farm Exposures and Allergic Disease Among Children Living in a Rural Setting.

OBJECTIVES: The purpose of this study was to examine the association between farm exposures and asthma and allergic disease in children while also highlighting the experiences of non-farm rural children. METHODS: This was a cross-sectional analysis of data collected from across the province of Saskatchewan, Canada in 2014. Surveys were completed by parents of 2275 rural dwelling children (farm and non-farm) aged 0 to 17 years within 46 rural schools. Questionnaires were distributed through schools for parents to complete. RESULTS: Asthma prevalence was 7.6%, of which 29.5% of cases were allergic. After adjustment for potential confounders, home location (farm vs non-farm) and other farm exposures were not associated with asthma and asthma phenotypes. Those who completed farm safety education were more likely to have asthma (11.7% vs. 6.7%; p = .001) compared to children without asthma. In sub-analyses among 6-12-year-old children, boys were more likely to have asthma (non-allergic) and use short-acting beta-agonists compared to girls. Doing farm work in the summer was associated with an increased risk of asthma [adjusted OR (aOR) = 1.71 (1.02-2.88); p = .041]. Doing routine chores with large animals was associated with an increased risk of asthma [aOR = 1.83 (1.07-3.15); p = .027] and allergic asthma [aOR = 2.37 (95%CI = 1.04-5.40); p = .04]. CONCLUSION: The present study showed that the prevalence of asthma and asthma phenotypes were similar between farm and non-farm rural children. There did not appear to be differential involvement in farming activities between those with and without asthma although those with asthma had more training suggesting possible attempts to mitigate harm from farm exposures.

Mental health and academic outcomes over the first year at university in international compared to domestic Canadian students.

OBJECTIVE: To compare risk factors and associated mental health and academic outcomes between international and domestic students. PARTICIPANTS: Canadian university undergraduate students. METHODS: Electronic surveys were completed at university entry and the end of first year. Surveys assessed demographics, risk factors, symptoms of mental disorders, and access to support. Academic outcomes were obtained from university databases. RESULTS: International students had comparable or lower rates of clinically significant anxiety, depression, and insomnia. Domestic female students reported the highest screening rates for common mental disorders. However, international students were more likely to report having attempted suicide. International students felt less connected to the university community and had lower academic performance. Psychosocial risk factor profiles and proportions accessing mental health services were similar. CONCLUSIONS: The scope of mental health need appears more similar than different between international and domestic students; however, international students may benefit from targeted academic and social support initiatives.

Probing bulk electronic structure with hard X-ray angle-resolved photoemission.

Traditional ultraviolet/soft X-ray angle-resolved photoemission spectroscopy (ARPES) may in some cases be too strongly influenced by surface effects to be a useful probe of bulk electronic structure. Going to hard X-ray photon energies and thus larger electron inelastic mean-free paths should provide a more accurate picture of bulk electronic structure. We present experimental data for hard X-ray ARPES (HARPES) at energies of 3.2 and 6.0 keV. The systems discussed are W, as a model transition-metal system to illustrate basic principles, and GaAs, as a technologically-relevant material to illustrate the potential broad applicability of this new technique. We have investigated the effects of photon wave vector on wave vector conservation, and assessed methods for the removal of phonon-associated smearing of features and photoelectron diffraction effects. The experimental results are compared to free-electron final-state model calculations and to more precise one-step photoemission theory including matrix element effects.

Dirac point degenerate with massive bands at a topological quantum critical point.

The quasilinear bands in the topologically trivial skutterudite insulator CoSb(3) are studied under adiabatic, symmetry-conserving displacement of the Sb sublattice. In this cubic, time-reversal and inversion symmetric system, a transition from trivial insulator to topological point Fermi surface system occurs through a critical point in which massless (Dirac) bands appear, and moreover are degenerate with massive bands. Spin-orbit coupling, while small due to the type of band character, coupled with tetragonal strain opens the gap required to give the topological insulator. The mineral skutterudite (CoSb(3)) is very near the critical point in its natural state.

A novel application of a data mining technique to study intersections in the social determinants of mental health among young Canadians.

OBJECTIVES: Adolescent mental health is an emergent clinical and public health priority in Canada. Gender-based differences in mental health are well established. The objective of this study was to evaluate a new data mining technique to identify social locations of young Canadians where differences in mental health between adolescent males and females were most pronounced. METHODS: We examined reports from 21,221 young Canadians aged 11-15 years (10,349 males, 10,872 females) who had responded to a 2018 national health and health behaviours survey. Using recursive partitioning for subgroup identification (SIDES), we identified social locations that were associated with the strongest differences between males and females for three reported mental health outcomes: positive psychosomatic health, symptoms of depression, and having a diagnosed mental illness. RESULTS: The SIDES algorithm identified both established and new intersections of social factors that were associated with gender-based differences in mental health experiences, most favouring males. DISCUSSION: This analysis represents a novel proof-of-concept to demonstrate the utility of a subgroup identification algorithm to reveal important differences in mental health experiences between adolescent males and females. The algorithm detected new social locations (i.e., where gender intersected with other characteristics) associated with poor mental health outcomes. These findings set the stage for further intersectional research, involving both quantitative and qualitative analyses, to explore how axes of discrimination may intersect to shape potential gender-based health inequalities that emerge during childhood.

Novel structural determinants of the human neutrophil chemotactic activity of leukotriene B.

A specific 5(S),12(R)-dihydroxy-eicosa-6,8,10(trans/trans/cis), 14(cis)-tetraenoic acid, designated leukotriene B, is generated by the lipoxygenation and subsequent enzymatic hydration of arachidonic acid in a variety of leukocytes. Leukotriene B elicits a maximal human neutrophil chemotactic response in vitro which is similar in magnitude to those evoked by the chemotactic fragment of the fifth component of complement, C5a, synthetic formyl-methionyl peptides, and 5-hydroxy-eicosatetraenoic acid (5-HETE). The neutrophil chemotactic potency of purified leukotriene B, assessed by the 50% effective concentration of 6 x 10(-9) M, is equivalent to that of C5a, but is up to 100-fold greater than that of 5-HETE and of other natural di-HETE isomers. 5(S),12(R)-di-hydroxy-eicosa-6,8,10(all-trans),14(cis)-tetraenoic acid, which differs from leukotriene B only in having a trans-double bond in place of a cis-double bond in the triene portion of the molecule, and acetyl-leukotriene B are significantly less potent neutrophil chemotactic factors than leukotriene B, which indicates that both the conjugated double bonds and the free hydroxyl-group(s) are functionally critical determinants. The capacity of acetyl-leukotriene B to inhibit competitively and selectively the human neutrophil chemotactic response to equimolar concentrations of leukotriene B suggests the existence of a specific subset of receptors for this potent lipid mediator.

Parallel electron-hole bilayer conductivity from electronic interface reconstruction.

The perovskite SrTiO3-LaAlO3 structure has advanced to a model system to investigate the rich electronic phenomena arising at polar oxide interfaces. Using first principles calculations and transport measurements we demonstrate that an additional SrTiO3 capping layer prevents atomic reconstruction at the LaAlO3 surface and triggers the electronic reconstruction at a significantly lower LaAlO3 film thickness than for the uncapped systems. Combined theoretical and experimental evidence (from magnetotransport and ultraviolet photoelectron spectroscopy) suggests two spatially separated sheets with electron and hole carriers, that are as close as 1 nm.

Limitations in fields of vision for simulated young farm tractor operators.

Farm tractors account for the majority of deaths and injuries among youths working on North American farms. A vehicle operator's field of vision is an important operational aspect for safe driving. However, very little is known about visual limitations of young tractor operators compared to adult operators. The main purpose of this study was to quantify limitations in fields of vision of children with different anthropometry. The study was based on assessment of 42 farm tractors in popular use in the USA. The results showed that youth operators typically had diminished fields of vision compared to the average adult operator. The degree of visual limitation is greatest for objects at close distances and when objects are straight in front of the operator/tractor. This has serious implications in terms of risks for runovers, rollovers and collisions. Study findings may help illuminate the development of policies and guidelines in tractor-related jobs for children. STATEMENT OF RELEVANCE: This study provides an ergonomic approach for evaluation of children's visual limitations in tractor operations. This approach could be used in other related cases, where children are allowed to operate vehicles.

Predictors of mental health and academic outcomes in first-year university students: Identifying prevention and early-intervention targets.

BACKGROUND: Although there is growing interest in mental health problems in university students there is limited understanding of the scope of need and determinants to inform intervention efforts. AIMS: To longitudinally examine the extent and persistence of mental health symptoms and the importance of psychosocial and lifestyle factors for student mental health and academic outcomes. METHOD: Undergraduates at a Canadian university were invited to complete electronic surveys at entry and completion of their first year. The baseline survey measured important distal and proximal risk factors and the follow-up assessed mental health and well-being. Surveys were linked to academic grades. Multivariable models of risk factors and mental health and academic outcomes were fit and adjusted for confounders. RESULTS: In 1530 students surveyed at entry to university 28% and 33% screened positive for clinically significant depressive and anxiety symptoms respectively, which increased to 36% and 39% at the completion of first year. Over the academic year, 14% of students reported suicidal thoughts and 1.6% suicide attempts. Moreover, there was persistence and overlap in these mental health outcomes. Modifiable psychosocial and lifestyle factors at entry were associated with positive screens for mental health outcomes at completion of first year, while anxiety and depressive symptoms were associated with lower grades and university well-being. CONCLUSIONS: Clinically significant mental health symptoms are common and persistent among first-year university students and have a negative impact on academic performance and well-being. A comprehensive mental health strategy that includes a whole university approach to prevention and targeted early-intervention measures and associated research is justified.

Theoretical Fermi-Surface Properties and Superconducting Parameters for K3C60.

Quantitative theories of superconductivity in alkali-doped C(60) require an accurate and detailed description of the Fermi surface. First-principles calculations of Fermi-surface properties and electronic parameters for K(3)C(60), the prototype fulleride-superconductor, are reported. The Fermi surface has two sheets; the first is free-electron-like, and the second is multiply-connected, forming two interlocked symmetry-equivalent pieces that never touch. The calculated (clean limit) London penetration depth is Lambda = 1600 A. Comparing the Fermi velocity with the experimental coherence length leads to a superconducting pairing strength lambda approximately 5, indicating very strong coupling. Partial nesting in the second Fermi-surface sheet may favor coupling to short-wavelength q,0,0 optic modes.

Fermi surfaces, fermi liquids, and high-temperature superconductors.

Recent experimental results are beginning to limit seriously the theories that can be considered to explain high-temperature superconductivity. The unmistakable observations of a Fermi surface, by several groups and methods, make it the focus of realistic theories of the metallic phases. Data from angle-resolved photoemission, positron annihilaton, and de Haas-van Alphen experiments are in agreement with band theory predictions, implying that the metallic phases cannot be pictured as doped insulators. The character of the low energy excitations ("quasiparticles"), which interact strongly with atomic motions, with magnetic fluctuations, and possibly with charge fluctuations, must be sorted out before the superconducting pairing mechanism can be given a microscopic basis.

Is recovery from ankle sprains negatively affected by obesity?

OBJECTIVE: Ankle sprains are common injuries that may lead to long-term morbidity. Individuals with obesity are at increased risk for ankle sprains; however, prognostic associations between body mass index (BMI) and recovery are less well understood. This study investigated whether BMI status affects recovery from ankle sprains. METHODS: We included individuals≥16 years old with grade 1 or 2 ankle sprains who sought emergency department treatment in Kingston, Ontario, Canada. Height in centimeters and weight in kilograms were measured at baseline by using a height rod and a standard medical column scale, respectively. BMI was calculated and categorized as non-overweight,<25.0kg/m2; overweight, 25.0-29.9kg/m2; and obese,≥30kg/m2. Recovery was assessed at 1, 3 and 6 months post-injury by the Foot and Ankle Outcome Score (FAOS). Continuous FAOS and binary recovery status were compared by BMI group at each assessment using a repeated measures linear mixed effects model and logistic regression, respectively. RESULTS: In total, 504 individuals were recruited and 6-month follow-up data were collected for 80%. We observed no significant differences in recovery at 1 and 3 months post-injury. At 6 months, between 53% and 66% of the participants were considered to have recovered according to the FAOS. The mean difference in unadjusted FAOS between participants classified as obese and non-overweight was -23.02 (95% confidence interval, -38.99 to -7.05) but decreased after adjusting for confounders. The odds ratio for recovery was 0.60 (0.37-0.97) before adjustment and 0.74 (0.43-1.29) after adjustment. Six-month recovery was significantly lower for participants with obesity than non-overweight participants on the FAOS Pain and Function in Daily Living subscales but were not clinically meaningful. CONCLUSIONS: All BMI groups showed improvements from ankle sprain over time. However, at 6 months, a sizeable proportion of the participants had not fully recovered particularly among individuals classified as obese. The findings suggest that individuals with obesity may benefit from specialized interventions focused on symptom management and functional activity.

Antitumor activity of sorafenib in FLT3-driven leukemic cells.

Activating internal tandem duplication (ITD) insertions in the juxtamembrane domain of the FLT3 tyrosine kinase are found in about one fourth of patients with acute myeloid leukemia and have been shown to be an independent negative prognostic factor for survival. We show that sorafenib (BAY 43-9006, Nexavar) potently inhibits FLT3 enzymatic and signaling activities. In HEK293 cells stably transfected with FLT3-WT or FLT3-ITD, sorafenib blocked basal and ligand dependent FLT3-mediated tyrosine autophosphorylation as well as extracellular signal-regulated kinase1/2 and Stat5 phosphorylation. In leukemia cell lines MV4-11 and EOL-1, sorafenib treatment resulted in decreased cell proliferation and inhibition of FLT3 signaling. The growth of the FLT3-independent RS4-11 cell line was only weakly inhibited by sorafenib. Cell cycle arrest and induction of apoptosis were observed upon treatment with sorafenib in MV4-11 and EOL-1 cells. The antitumor efficacy of sorafenib was evaluated against the MV4-11 leukemia grown subcutaneously in NCr nu/nu mice. Doses of 3 and 10 mg/kg administered orally for 14 days resulted in six and nine out of 10 animals with complete responses, respectively. The demonstration that sorafenib exhibits potent target inhibition and efficacy in FLT3-driven models suggests that this compound may have a therapeutic benefit for patients with FLT3-driven leukemias.

Prevention of agricultural injuries: an evaluation of an education-based intervention.

OBJECTIVE: To evaluate the effectiveness of an agricultural health and safety program in reducing risks of injury. DESIGN: Cross-sectional survey. SETTING: 50 rural municipalities in the Province of Saskatchewan, Canada. INTERVENTION: The Agricultural Health and Safety Network (AHSN), a mainly educational program that administered 112 farm safety interventions over 19 years. SUBJECTS: 5292 farm people associated with 2392 Saskatchewan farms. Farms and associated farm people were categorized into three groups according to years of participation in the AHSN. IMPACT: self-reported prevalence of: (1) farm safety practices; (2) physical farm hazards. OUTCOME: (1) self-reported agricultural injuries. RESULTS: After adjustment for group imbalances and clustering at the rural municipality level, the prevalence of all impact and outcome measures was not significantly different on farms grouped according to years of AHSN participation. To illustrate, the adjusted relative risk of reporting no rollover protection on tractors among farms with none (0 years) versus high (>8 years) levels of AHSN participation was 0.95 (95% CI 0.69 to 1.30). The adjusted relative risk for agricultural injuries (all types) reported for the year before the survey was 0.99 (95% CI 0.74 to 1.32). CONCLUSIONS: Educational interventions delivered via the AHSN program were not associated with observable differences in farm safety practices, physical farm hazards, or farm-related injury outcomes. There is a need for the agricultural sector to extend the scope of its injury prevention initiatives to include the full public health model of education, engineering, and regulation.

Pain and self-reported health in Canadian children.

BACKGROUND: Despite increasing attention to the epidemiology of pain, relatively little is known about the association between pain and health in children. In particular, no studies have examined this relationship in the general population of children in Canada. OBJECTIVES: To assess the association between self-reported pain experiences and health in school children in southeastern Ontario. Health measures included perceived health status, psychological complaints and satisfaction with school. METHODS: A total of 495 nine- to 13-year-old school children completed the Pain Experience Interview -- Short Form and health-related questions from the Health Behaviour in School-aged Children questionnaire. RESULTS: Of the 495 children in the present study, 8% rated their health as 'fair' to 'poor', 56% reported experiencing at least one of four psychological symptoms more than once a week and 24% said they disliked school. The strongest associations existed between headaches and poor self-rated health (OR=10.1; 95% CI 1.3 to 78.3), recurrent pain and psychological outcomes (OR=3.6; 95% CI 2.0 to 6.3), and recurrent pain and disliking school (OR=3.6; 95% CI 1.9 to 6.7). DISCUSSION: These findings indicate that common childhood pains are associated with childhood health. Further studies are needed to assess the causal relationship between pain and health in children, to obtain a more comprehensive understanding of the personal and economic impact of childhood pain, and to monitor changes in the lives of children living with chronic pain.

Local Moment Instability of Os in Honeycomb Li2.15Os0.85O3.

Compounds with honeycomb structures occupied by strong spin orbit coupled (SOC) moments are considered to be candidate Kitaev quantum spin liquids. Here we present the first example of Os on a honeycomb structure, Li2.15(3)Os0.85(3)O3 (C2/c, a = 5.09 Å, b = 8.81 Å, c = 9.83 Å, ß = 99.3°). Neutron diffraction shows large site disorder in the honeycomb layer and X-ray absorption spectroscopy indicates a valence state of Os (4.7 ± 0.2), consistent with the nominal concentration. We observe a transport band gap of Δ = 243 ± 23 meV, a large van Vleck susceptibility, and an effective moment of 0.85 µB, much lower than expected from 70% Os(+5). No evidence of long range order is found above 0.10 K but a spin glass-like peak in ac-susceptibility is observed at 0.5 K. The specific heat displays an impurity spin contribution in addition to a power law ∝T(0.63±0.06). Applied density functional theory (DFT) leads to a reduced moment, suggesting incipient itineracy of the valence electrons, and finding evidence that Li over stoichiometry leads to Os(4+)-Os(5+) mixed valence. This local picture is discussed in light of the site disorder and a possible underlying quantum spin liquid state.

The epidemiology of non-fatal injuries among 11-, 13- and 15-year old youth in 11 countries: findings from the 1998 WHO-HBSC cross national survey.

The primary objective was to present a cross-country comparison of injury rates, contexts and consequences. The research design was the analysis of data from the 1998 cross-national Health Behaviour in School-aged Children survey and 52955 schoolchildren from 11 countries, aged 11, 13 and 15 years, completed a self-administrated questionnaire. A total of 41.3% of all children were injured and needed medical treatment in the past 12 months. Injury rates among boys were higher than among girls, 13.3% reported activity loss due to injury and 6.9% reported severe injury consequences. Most injuries occurred at home and at a sport facility, mainly during sport activity. Fighting accounted for 4.1% of injuries. This paper presents the first cross-national comparison of injury rates and patterns by external cause and context. Findings present cross-country similarities in injury distribution by setting and activity. These findings emphasize the importance of the development of global prevention programmes designed to address injuries among youth.