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To compare two reciprocating NiTi systems operated by novices for use in curved root canals. Fifty mesial roots of extracted mandibular first molars, with 2-2 canal configuration, were scanned with micro-CT and divided into 2 groups according to canal length and curvature: Reciproc and WaveOne. Each system was used to prepare one of the two canals by fourth-year dental students, who were new to reciprocating files and were blinded to the system being used. After another scanning, the pre- and post-instrumentation images were compared 3-dimensionally in software. Some 43 to 46% of the canal wall area remained un-instrumented. Significantly higher proportions of canals were transported towards the isthmus or furcation aspect than the mesial or external aspect. Mean transported distance was the greatest in the coronal one-third. Remaining dentine wall was the thinnest at the furcal aspect near the middle root region. No significant difference was noted between the two brands in the parameters examined. Both brands of reciprocating file left similar amounts of un-instrumented canal wall, and resulted in similar extent of canal transportation. NiTi reciprocating files can safely be used by new users to prepare curved root canals into a predictable shape.

Background Suicide is a major cause of mortality for individuals with schizophrenia spectrum disorders (SSD). Understanding the risk factors for suicide at time of diagnosis can aid clinicians in identifying people at risk. Methods Records from linked administrative health databases in Ontario, Canada were used to identify individuals aged 16 through 45 years who received a first lifetime diagnosis of SSD (schizophrenia, schizoaffective disorder, psychotic disorder not otherwise specified (NOS)) using a validated algorithm between 01/01/1993 and 12/31/2010. The main outcome was death by suicide following cohort entry until 12/31/2012. Outcomes 75,989 individuals with a first SSD diagnosis (60.1% male, 39.9% female) were followed for an average of 9.56 years. During this period, 1.71% of the total sample (72.1% male, 27.9% female) died by suicide, after an average of 4.32 years. Predictors of suicide death included male sex (HR 2.00, 95% CI 1.76–2.27), age at diagnosis between 26 and 35 (HR 1.27, 95% CI 1.10–1.45) or 36–45 (HR 1.34, 95% CI 1.16–1.54), relative to 16–25, and suicide attempt (HR 2.23, 95% CI 1.86–2.66), drug use disorder (HR 1.21, 95% CI 1.04–1.41), mood disorder diagnosis (HR 1.32, 95% CI 1.17–1.50), or mental health hospitalization (HR 1.30 95% CI 1.13–1.49) in the 2 years prior to SSD diagnosis. Interpretation Death by suicide occurs in 1 out of every 58 individuals and occurred early following first diagnosis of SSD. Psychiatric hospitalizations, mood disorder diagnoses, suicide attempts prior to SSD diagnosis, as well as a later age at first diagnosis, are all predictors of suicide and should be integrated into clinical assessment of suicide risk in this population.

International audience; The photoinitiation abilities of three 1,2-diketones [i.e., acenaphthenequinone (ANPQ), aceanthrenequinone (AATQ), and 9,10-phenanthrenequinone (PANQ)]-based photoinitiating systems [PISs, with additives such as iodonium salt, N-vinylcarbazole (NVK), tertiary amine, and phenacyl bromide (R-Br)] for cationic photopolymerization and free-radical photopolymerization under the irradiation of ultraviolet (UV; 392 nm) or blue (455 nm) light-emitting diode (LED) bulb are investigated. All 1,2-diketones studied exhibit ground state absorption that match with the emission spectra of UV (392 nm) or blue LED (455 nm) better than that of the well-known blue-light-sensitive photoinitiator camphorquinone (CQ). In particular, AATQ/iodonium salt/NVK can show high photoinitiating ability (with epoxide conversion yield >70%) under the UV light irradiation due to the effect of NVK. In addition, 1,2-diketone/iodonium salt (and optional NVK) systems are capable of initiating free-radical photopolymerization of methacrylates, with conversions of 50–58%. Furthermore, some 1,2-diketone/tertiary amine (and optional R-Br) combinations are found to demonstrate high efficiency to initiate free-radical photopolymerization, and 71% of methacrylate conversion can be achieved with PANQ/tertiary amine/R-Br PIS. Some 1,2-ketone-based PISs can even exhibit higher efficiency than the CQ-based systems. The photochemical mechanism of the radical generation from the 1,2-diketone-based PISs is investigated and found to be consistent with the related photopolymerization efficiency.

The theory of Computational Singular Perturbation (CSP) has been widely used in the chemical kinetics and combustion community to understand complex chemistry, reduce chemical kinetic models and perform computational diagnostics in reacting flow simulations. Useful as it is, the application of CSP is nevertheless subject to computationally expensive eigen-decomposition of the chemical Jacobian matrix, especially for mechanisms involving a large number of species. In 2016–2017, a new CSP approach was developed by Lam, taking advantage of species lifetime and linearity in the governing equation of the fastest species. The corresponding quasi-state value of the current fastest species across the thin transition layer could be accurately predicted at each time step, during which period the concentration of the slower species is considered as constant. As a result, tedious explicit integration to resolve the apparent exponential transition layer, as those utilized in conventional implicit chemistry solvers (e.g., CVODE), is avoided and the integration time step could be largely extended. This method, referred to as linear CSP (LCSP), has been demonstrated to be useful in deriving reduced models and to numerically integrate stiff ODE systems. In 2018, an idea of nonlinear CSP (NCSP) following similar approach was further proposed by Lam, which abandons the enabling assumptions of the linearized governing equation for the fastest species and provides useful insights into the numerical integration of stiff chemical ODE systems. The development of CSP without expensive eigen-decomposition and computational evidence supporting its implementation are discussed and disseminated as a promising direction of advanced CSP theory. For general kinetic problems with complex couplings, a method based on sparse adaptive hybrid integration is introduced to demonstrate the redundancy issue and general stiffness in the fast subspace.

A cross-national qualitative suicide study was conducted by Tsinghua University and the University of Toronto with two samples of Chinese women in Beijing and Toronto. The aim of this article is to reflect on lessons learned from this collaborative study. A literature review guided the analysis. A focus group was conducted with members of both research teams. A semi-structured interview guide was developed to explore the researchers' experiences of participating in the cross-national study. Focus group transcript data and observations from authors informed the analysis, situated in the existing literature on cross-national qualitative health research and guided by Baistow's cross-national research frame. Our study highlights how cross-national research involves conceptual and practical challenges that require negotiation. Such research also holds many opportunities, including (1) using a different cultural lens to understand differences and clarify similarities cross-culturally; (2) co-constructing knowledge through collaboration; (3) deconstructing one's own assumptions; and (4) engaging in an inspiring and empowering experience in collaboration.

To compare two reciprocating NiTi systems operated by novices for use in curved root canals.Fifty mesial roots of extracted mandibular first molars, with 2-2 canal configuration, were scanned with micro-CT and divided into 2 groups according to canal length and curvature: Reciproc and WaveOne. Each system was used to prepare one of the two canals by fourth-year dental students, who were new to reciprocating files and were blinded to the system being used. After another scanning, the pre- and post-instrumentation images were compared 3-dimensionally in software.Some 43 to 46% of the canal wall area remained un-instrumented. Significantly higher proportions of canals were transported towards the isthmus or furcation aspect than the mesial or external aspect. Mean transported distance was the greatest in the coronal one-third. Remaining dentine wall was the thinnest at the furcal aspect near the middle root region. No significant difference was noted between the two brands in the parameters examined.Both brands of reciprocating file left similar amounts of un-instrumented canal wall, and resulted in similar extent of canal transportation.NiTi reciprocating files can safely be used by new users to prepare curved root canals into a predictable shape.

Suicide is a complex and tragic outcome driven by biological, psychological, social and cultural factors. Women of Chinese descent and women who have immigrated to other countries have higher rates of suicidal ideation and behaviour, and immigration-related stress may contribute. To understand the experiences of immigration and their relationship with distress and suicide-related behaviour in Chinese women who have immigrated to Canada. 10 semi-structured qualitative interviews with Chinese women who have immigrated to Toronto, Canada and have a history of suicide-related behaviour were completed and analyzed using a constructivist grounded theory methodology. Immigration-related and acculturation stress stemmed from unmet expectations and harsh realities. These repeated experiences resulted in hopelessness, helplessness, and alienation, which are risk factors for suicide and suicide-related behaviour. However, immigration-related support can also increase hope, self-efficacy and connectedness to foster recovery and resilience. This is the first qualitative study focusing on immigration experiences and its relationship to suicide-related behaviour in Chinese immigrant women. Knowledge of immigration and acculturation stressors can a) help identify and support women at risk for suicide and b) form a target for social intervention for all immigrant women, regardless of suicide risk.

An efficient formulation of computational singular perturbation (CSP) is proposed for toy problems that consist of three variables. The essence of the new CSP formulation is to take advantage of sh...

This qualitative study explored the experiences and patterns of recovery of Chinese-born women living in Canada with a history of suicidal behaviour. It explores a number of dimensions of recovery including clinical, existential, functional, physical, and social. The women described engaging in “survival” recovery in the short term and “thriving” recovery in the long term, with survival strategies extending into the thriving phase of recovery during their complex path to it. The survival recovery phase included accessing culturally sensitive mental health care and obtaining social and instrumental support to help ensure safety, manage stress, and treat psychiatric symptoms. The thriving phase of recovery was described as involving six components: developing an explanatory model with their health care provider; undertaking a process of narrative reflection and prioritizing self-care; engaging in interdisciplinary care team support; engaging the support of family and friends; exploring spiritual and existential supports; and creating goals for the future and a sense of mastery. Through these six avenues, the women began to experience a sense of self-efficacy and agency that improved their ability to cope with stress and pressure, leading to building a life with meaning. The interviews provided insights into how clinical care can be improved and how practitioners can implement a more recovery-oriented approach to practice.

The effect of pH (5.0 or 7.0) and temperature (25.0, 65.0 and 95.0 °C) on the physicochemical and emulsifying properties of type-1 (with calcium, ALA-1) and type-3 (without calcium, ALA-3) alpha-lactalbumin (ALA) were examined. By increasing the temperature of pre-treatment, changes in ALA conformation allowed for greater surface hydrophobicity and caused changes in its surface charge. pH also influenced surface charge for ALA where enhanced repulsion at pH 7.00 was observed resulting in reduced aggregation despite having greater hydrophobicity. Findings indicate that changes to protein conformation using various pH and temperature pre-treatments influenced their surface chemistry, aggregation and ability to align at the oil–water interface. Overall, emulsions were found to be more stable at pH 7.0 than 5.0 due to the greater amount of electrostatic repulsive forces between droplets present at pH 7.0. Under the conditions examined in this study, ALA-3 pre-treated at 65 °C and at pH 7.00 resulted in the best emulsifying properties.

Biodegradable edible films have the potential to either replace or reduce the amount of synthetic packaging utilized by the food industry. The overall goal of this research was to investigate the effect of flax seed oil concentration (1–10%) on the mechanical, moisture barrier and swelling properties of soy protein isolate (SPI) (5.0% w/w SPI, 40% w/w glycerol) emulsion-based films. Film forming solutions showed a bimodal oil droplet distribution with peak sizes occurring at < 10 and ~ 100 μm. As the oil content increased, the size distribution shifted towards smaller droplet sizes. An equal size ratio was noted at the 5.0% oil content level. All film forming solutions were pseudoplastic in nature, where viscosity increased from 18 to 58 mPa (at 1 s− 1) as a function of oil content (3% to 10%). Tensile strength of formed films reached a maximum at 5.35 MPa at the 5% w/w oil level, whereas tensile elongation increased from 11.3% to 22.2% with increasing oil content. Puncture strength and deformation, as well as water vapour permeability was relatively independent of the oil content. Moisture content and swelling properties of formed films were found to both decrease from 22.8% to 18.7%, and from 3114% to 1209%, respectively as the oil content was raised from 1 to 10%, and films became darker, redder and more yellow in colour as the percentage of flax seed oil increased.

The overall goal of this research was to investigate the emulsifying properties of whey protein isolate (WPI) as a function of pH (3.0, 5.0, 7.0) and temperature pre-treatments (25, 55, 85 °C). Specifically, the physicochemical (charge and hydrophobicity, size, interfacial tension) and emulsifying (emulsification activity (EAI) and stability indices (ESI)) properties were assessed. Overall, hydrophobicity was greatest at pH 5.0/85 °C. Charge was found to decrease linearly from ∼ +40 mV at pH 3.0 to ∼ −40 mV at pH 7.0, where net neutrality was observed between pH 5.1 and 5.4. Aggregate size was greatest at pH 5.0 relative to the other pHs, however it declined in size at pH 5.0 from 1589 nm to 1450 nm and then to 832 nm as temperature pre-treatments increased from 25 °C to 55 °C and then to 85 °C, respectively. Interfacial tension was reduced from ∼28 mN/m to ∼14–18 mN/m for systems in the absence and presence of WPI, respectively, with little differences seen among treatments. EAI was found to increase under conditions where WPI aggregation was reduced, whereas ESI increased under conditions away from its isoelectric point where electrostatic repulsive forces were strongest and under conditions where surface hydrophobicity was reduced.

The rheological properties of whey protein isolate (WPI) and WPI with carrageenan (CG) (kappa-, iota- and lambda-types) mixtures during a slow acidification process were investigated in a non-emulsified and emulsified system. For all systems, electrostatically coupled networks were formed leading to the formation of a biopolymer or emulsion-based gel network. However, network strength differed depending on the CG-type. In the case of biopolymer gels, the storage modulus within the plateau zone for WPI–kappa-CG and WPI–iota-CG mixtures were ~ 93 and ~ 73 Pa, respectively, whereas the WPI–lambda-CG network was weaker (~ 8 Pa). The gel point corresponded to the pH where complex coacervation occurred. WPI–CG mixtures were also able to lower interfacial tension from 28 to 18–22 mN/m before gelation. Emulsion gels followed a similar trend as the biopolymer networks, except they were stronger (WPI–kappa-CG, WPI–iota-CG and WPI–lambda-CG systems had storage moduli of ~ 435, ~ 320 Pa and ~ 103 Pa, respectively). The presence of CG decreased the average droplet size of these emulsions from ~ 38 to ~ 32 μm, regardless of the CG type. Protein stabilized emulsion gels were presumed to form, where upon complexation with CG, flocculation between droplets was promoted until an electrostatic-stabilized gel network was formed within the continuous phase. The WPI control did not gel for both non-emulsified and emulsified systems.

Aim: Real-time traveler information affects auto commuter’s travel behavior. Method: An ordered probit model is used to analyze auto commuter’s mode switching propensity under influence of simulated real-time multimodal traveler information. A travel preference survey is administered to car drivers to gather individual commuter’s travel decisions under integrated multimodal traveler information. Result: It is shown that integrated multimodal traveler information can influence willingness of car drivers to switch mode of travel, while socio-economic characteristics also influence the mode choice decision.

Literacy is a multilevel construct comprising word reading, spelling, and text reading comprehension. Understanding the key linguistic and cognitive factors that support word reading, spelling, and text reading comprehension is fundamentally important to elucidate the detailed nature of literacy acquisition. While most contemporary models of literacy acquisition are developed on the basis of English and other alphabetic writing systems, little attention has been paid to nonalphabetic writing system, such as Chinese. We focus on Chinese literacy acquisition and emphasize how different properties of the Chinese language (phonology, morphology, and orthography) may impact the development of different-level literacy skills. A systematic review of extant research on literacy acquisition, along with our own work on Chinese word reading, spelling, and reading comprehension, suggests that phonological awareness, morphological awareness, and orthographic skills are all important to Chinese literacy acquisition, but the relative importance of these skills varies across word reading, spelling, and reading comprehension. Moreover, the contribution of each of these linguistic and cognitive skills to a single component of literacy skills also varies in different developmental stages. This suggests that a full model of literacy acquisition should consider the linguistic features that are characteristics of the writing system, as well as developmental context.