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Prematurity in newborns is a condition that is associated with worse hospital outcomes when compared to birth to term. A preterm infant (PI) is classified when gestational age (GA)37 wk.To analyze prognostic indicators related to the use of oxygen therapy, non-invasive ventilation (continuous positive airway pressure) and mechanical ventilation (MV) in PI.This is a retrospective cohort. The sample was composed of PIs from a private hospital in southern Brazil. We included neonates with GA37 wk of gestation in the period of January 1, 2018 to December 31, 2018. For data collection, electronic records were used in the Tasy PhilipsIn total, 90 PI records were analyzed. The median (p25-p75) of GA was 34.0 (31.9-35.4) wk, and there were 45 (50%) males. The most common morbidity among PIs was the acute respiratory discomfort syndrome, requiring hospitalization in the neonatal intensive care unit in 76 (84.4%) cases. The utilization rate of oxygen therapy, continuous positive airway pressure and MV was 12 (13.3%), 37 (41.1%) and 13 (14.4%), respectively. The median (p25-p75) length of stay was 12.0 (5.0-22.2) d, with 10 (11.1%) deaths. A statistical association was observed with the use of MV and GA28 wk, lower maternal age, low birth weight, Apgar8 and neonatal deaths.The identification of factors related to the need for MV in prematurity may help in the indication of a qualified team and technologies to promptly meet the unforeseen events that may occur after birth.

Individuals with mental illness often live in chronic poverty, which is associated with personal health practices such as tobacco use and poor nutrition that disrupt physical health. The purpose of our study was to examine whether differences exist in personal health and health practices - related to nutrition, physical activity, smoking, alcohol consumption and sleep - between a cohort of individuals with mental illness in southwestern Ontario and the general Canadian population.The study sample consisted of 250 individuals who had had a psychiatric diagnosis for at least one year. We conducted a structured quantitative interview with each person to gather information about their personal health and health practices, using question wording from the National Population Health Survey and the Canadian Community Health Survey. We calculated 95% confidence intervals for our results and used them to compare our data with Canadian norms.Individuals with mental illness are significantly more likely than the general population to have a poor diet, experience poor sleep and consume alcohol in excess.It is important for nurses, health-care organizations and policy-makers to be aware that a number of factors may be influencing the personal health and health practices of individuals with mental illness and that this population may require different health promotion strategies to support a healthy lifestyle.

Accessible summary Studies have indicated that individuals who are homeless access hospital emergency departments more frequently and may have different needs than individuals who are housed. Successful interventions have been developed and tested to reduce discharge to homelessness for psychiatric inpatients but have not been similarly tested for discharge from emergency departments. This study was developed to provide baseline data on this issue to inform future emergency department interventions. Findings from the current study suggest that discharge from emergency departments to homelessness happens frequently in London, Canada. Participants are unlikely to spontaneously disclose their housing/homelessness issue when first entering the emergency department, which may result in services that do not adequately meet their complex needs. Screening for housing issues is necessary within emergency departments and psychiatric crisis teams as housing issues may be a reason for accessing care or contribute to the presenting condition. Nurses are in an ideal position to evaluate housing needs among emergency department patients. Services outside of the emergency department are also needed to address housing issues, particularly outside of regular office hours. Abstract Individuals who have mental health issues and are homeless or in housing crisis have been found to access emergency departments more frequently than individuals with stable housing. While emergency departments primarily focus on medical issues, homeless individuals may require psychosocial support as well. This study examined issues around housing crises and emergency department use for individuals with mental illness in Canada. Collecting baseline data about these issues is important to inform subsequent interventions. Administrative data from a hospital emergency department and psychiatric crisis service were collected, and five individuals accessing the emergency department for psychiatric reasons were interviewed. Results indicated that individuals with an identified housing crisis accessed the emergency department 930 times in 6 months. None of the interview participants identified housing as the primary reason for accessing the emergency department, but all noted that housing was a contributing stressor. Future research is needed to examine ways in which discharge to homelessness from emergency departments can be avoided and identify alternative services to address housing concerns, particularly for individuals with mental illness. Crisis service and emergency department staff, especially nurses, can play an important role in screening for housing issues and connecting individuals to outside services.

Proper alignment is critical to obtain the desired performance from focused spatially chirped beams, for example in simultaneous spatial and temporal focusing (SSTF). We present a simple technique for inspecting the beam paths and focusing conditions for the spectral components of a broadband beam. We spectrally resolve the light transmitted past a knife edge as it was scanned across the beam at several axial positions. The measurement yields information about spot size, M2, and the propagation paths of different frequency components. We also present calculations to illustrate the effects of defocus aberration on SSTF beams.

We propose two schemes for generating pure circularly polarized isolated attosecond pulses by crossing two non-collinear counter-rotating circularly polarized pulses. Isolation of a single attosecond pulse can be achieved either using few-cycle or multi-cycle drivers.

We demonstrate a spectral interferometric method to characterize lateral and angular spatial chirp to optimize intensity localization in spatio-temporally focused ultrafast beams. Interference between two spatially sheared beams in an interferometer will lead to straight fringes if the wavefronts are curved. To produce reference fringes, we delay one arm relative to another in order to measure fringe rotation in the spatially resolved spectral interferogram. With Fourier analysis, we can obtain frequency-resolved divergence. In another arrangement, we spatially flip one beam relative to the other, which allows the frequency-dependent beamlet direction (angular spatial chirp) to be measured. Blocking one beam shows the spatial variation of the beamlet position with frequency (i.e., the lateral spatial chirp).

BACKGROUND For people with mental illness (psychiatric survivors), seeking and securing employment involves personal, social, and environmental factors. In Canada, psychiatric survivors are under-represented in the workforce, and services can help by tailoring their supports to help make the most gains in employment. OBJECTIVE Determine whether individual socio-demographic and health factors predict seeking and securing employment among psychiatric survivors. METHODS A community sample of psychiatric survivors from a Southwestern Ontario region participated in this study. Stepwise logistic regression was used to analyze data from 363 participants who had completed a variety of questionnaires to ascertain individual characteristics and employment outcomes. RESULTS Health service utilization, living circumstances, homelessness, substance use issues, general health, social integration, ethnicity, having children under 18, and being a student emerged as significant predictors of seeking and securing work. Other commonly accepted human capital indicators, such as education and age, were not predictive of employment search behavior and outcomes. CONCLUSIONS Individual characteristics that predict employment search and success outcomes for psychiatric survivors include aspects related to treatment and living circumstances, which stands in contrast to predictors of employment for the general population, suggesting that employment support services may need to be tailored to psychiatric survivors specifically.

We present a method using spectral interferometry (SI) to characterize a pulse in the presence of an incoherent background such as amplified spontaneous emission (ASE). The output of a regenerative amplifier is interfered with a copy of the pulse that has been converted using third-order cross-polarized wave generation (XPW). The ASE shows as a pedestal background in the interference pattern. The energy contrast between the short-pulse component and the ASE is retrieved. The spectra of the interacting beams are obtained through an improvement to the self-referenced spectral interferometry (SRSI) analysis.

Simultaneous spatially and temporally focussing (SSTF) of ultrashort pulses allows for an unprecedented control of the intensity distribution of light. It has therefore a great potential for widespread applications ranging from nonlinear microscopy, ophthalmology to micro-machining. SSTF also allows to overcome many bottlenecks of ultrashort pulse micro-machining, especially non-linear effects like filamentation and self-focussing. Here, we describe and demonstrate in detail how SSTF offers an additional degree of freedom for shaping the focal volume. In order to obtain a SSTF beam, the output of an ultrafast laser is usually split by a grating into an array of copies of the original beam, which we refer to as beamlets. The ratio of the beamlet array width to the width of the invidual beamlet is the beam aspect ratio. The focal volume of the SSTF beam can now be tailored transversally by shaping the cross-section of the beamlets and axially by choosing the right beam aspect ratio. We will discuss the requirements of the setup for a successful implementation of this approach: Firstly, the group velocity dispersion and the third order dispersion have to be compensated in order to obtain a high axial confinement. Secondly, the beamlet size and their orientation should not vary too much spectrally. Thirdly, beamlet and SSTF focus should match. We will hence demonstrate how SSTF allows to inscribe tailored three-dimensional structures with fine control over their aspect ratio. We also show how the SSTF focus can be adapted for various glasses and crystals.

To optimize intensity-localization in spatio-temporally focused ultrafast beams we demonstrate spectral interferometric and spectrally-resolved knife edge scan methods to characterize lateral and angular spatial chirp. A novel dispersion scan yields the focused-pulse spectral phase.

Spatial chirp can be manipulated to control the focusing conditions for materials processing. Our double-ABCD nonparaxial analysis helps to understand and exploit the mechanisms for intensity localization, pulse front tilt, and grating formation, and includes initial spectral phase and detuning of the wavelength crossing plane. We also present a novel method for creating high density, high intensity interference patterns with crossed beams that have no relative pulse front tilt. 1. Non-paraxial double ABCD tracing The properties of space-time focused beams are strongly dependent of the nature of the spatial overlap of the frequency components. The analysis of optical systems with spatial chirp is therefore critical both for understanding the unusual properties of these beams and for designing systems to exploit these properties for materials processing. In a recent paper, we developed an analytical approach to calculate the propagation of spatially chirped beams. A ray is traced that represents the central axis of the Gaussian beamlet for each frequency component. Since one form of the calculation is nonparaxial, the beamlet angles can be large and the calculation is valid over a wider range of conditions than direct Fresnel propagation. Our technique explains, for example, how the evolution of the beamlet radius of curvature leads to an axial variation of the spectral chirp through the focus, contributing to the axial intensity localization. It also allows the derivation of simple scaling properties of the beam, showing that the improvement of the localization over the confocal parameter of the focused beamlets depends primarily on the degree of spatial chirp, not on the initial pulse duration or the focal length.

The efficiency and beam quality of double-pass cross-polarized wave generation is improved by using imaging to better match the two fields for the second pass. The efficiency increase is especially pronounced for low input energy.

Space-time focusing of spatially-chirped Ti:Sapphire laser pulses is used to generate a plasma in air axially localized to 28× less than the confocal parameter, suppressing filamentation on the way to the focus.

We interfere an amplified output pulse with a copy that has been converted using third-order cross-polarized wave generation. The ASE pedestal shows as a background in the interference, yielding the short-pulse/ASE energy contrast.

The conversion efficiency of cross-polarized wave (XPW) generation can be improved using two separate thinner nonlinear crystals versus a single thick one, due to the evolution of the beam sizes and individual phases after the first crystal. In this paper, we present an alternative scheme in which a curved mirror is used to reimage a plane just after the BaF2 crystal for a second pass. We also develop a simple analytic model for XPW conversion that describes the origin of a nonlinear phase mismatch and nonlinear lensing for both the fundamental wave and XPW. Coupled with the numerical solution for the process and the Fresnel propagation after the first pass, we also explore the factors that affect the efficiency of saturated, seeded XPW conversion. These include the development of the on-axis relative phase difference in the first crystal and after it (during free-space propagation), mode matching, wavefront curvature difference, and crystal tuning angle. We also experimentally demonstrate that the beam quality of the XPW signal after the second pass can be improved by the reimaging.