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Characterization of crystallization processes in situ is of great importance to furthering knowledge of how nucleation and growth processes direct the assembly of organic and inorganic materials in solution and, critically, understanding the influence that these processes have on the final physico‐chemical properties of the resulting solid form. With careful specification and design, as demonstrated here, it is now possible to bring combined X‐ray diffraction and Raman spectroscopy, coupled to a range of fully integrated segmented and continuous flow platforms, to the laboratory environment for in situ data acquisition for timescales of the order of seconds. The facility used here (Flow‐Xl) houses a diffractometer with a micro‐focus Cu Kα rotating anode X‐ray source and a 2D hybrid photon‐counting detector, together with a Raman spectrometer with 532 and 785 nm lasers. An overview of the diffractometer and spectrometer setup is given, and current sample environments for flow crystallization are described. Commissioning experiments highlight the sensitivity of the two instruments for time‐resolved in situ data collection of samples in flow. Finally, an example case study to monitor the batch crystallization of sodium sulfate from aqueous solution, by tracking both the solute and solution phase species as a function of time, highlights the applicability of such measurements in determining the kinetics associated with crystallization processes. This work illustrates that the Flow‐Xl facility provides high‐resolution time‐resolved in situ structural phase information through diffraction data together with molecular‐scale solution data through spectroscopy, which allows crystallization mechanisms and their associated kinetics to be analysed in a laboratory setting. [ABSTRACT FROM AUTHOR]

Laval nozzles are used in the CRESU ("Cinétique de Réaction en Écoulement Supersonique Uniforme") method to generate a collimated low temperature (5–200 K), low pressure (30–500 Pa), high Mach number (1 < M < 20) supersonic jet. Laval nozzles have been designed using the Method of Characteristics (MOC) since the development of CRESU, which is an analytical method that assumes inviscid, isentropic flow, and is routinely used to design nozzle profiles for a particular gas and temperature with a uniform shock free exit. This study aims to provide a robust computational framework to overcome the limitations of the MOC while also providing recommendations on the numerical model setup required to model a low-temperature supersonic jet. It also discusses the blockage effects when using the Pitot tube method for flow characterization, the influence of inlet turbulence and reservoir size. Numerical results are validated using two different experimental apparatuses from research groups at the University of Leeds and the University of Birmingham. Finally, a MATLAB framework was developed and has been provided as an open source toolbox to allow any user to perform computational fluid dynamics on any Laval nozzle, with the ability to change nozzle geometry, operating conditions and bath gas. The toolbox has been rigorously tested against many benchmark cases, which shows that steady-state Reynolds-averaged Navier–Stokes with the k-omega-shear stress transport turbulence model can be used to accurately predict global quantities, such as average temperature in the stable region of the supersonic jet. [ABSTRACT FROM AUTHOR]

Background: We investigated disparities in the clinical management of self-harm following hospital presentation with self-harm according to level of socio-economic deprivation (SED) in England. Methods: 108 092 presentations to hospitals (by 57 306 individuals) after self-harm in the Multicenter Study of Self-harm spanning 17 years. Area-level SED was based on the English Index of Multiple Deprivation. Information about indicators of clinical care was obtained from each hospital's self-harm monitoring systems. We assessed the associations of SED with indicators of care using mixed effect models. Results: Controlling for confounders, psychosocial assessment and admission to a general medical ward were less likely for presentations by patients living in more deprived areas relative to presentations by patients from the least deprived areas. Referral for outpatient mental health care was less likely for presentations by patients from the two most deprived localities (most deprived: adjusted odd ratio [aOR] 0.77, 95% CI 0.71–0.83, p < 0.0001; 2nd most deprived: aOR 0.80, 95% CI 0.74–0.87, p < 0.0001). Referral to substance use services and 'other' services increased with increased SED. Overall, referral for aftercare was less likely following presentations by patients living in the two most deprived areas (most deprived: aOR 0.85, 95% CI 0.78–0.92, p < 0.0001; 2nd most deprived: aOR 0.86, 95% CI 0.79–0.94, p = 0.001). Conclusions: SED is associated with differential care for patients who self-harm in England. Inequalities in care may exacerbate the risk of adverse outcomes in this disadvantaged population. Further work is needed to understand the reasons for these differences and ways of providing more equitable care. [ABSTRACT FROM AUTHOR]

Background: Few studies have examined online experience by young people who die by suicide. Methods: A 3-year UK-wide consecutive case series of all young people aged 10–19 who died by suicide, based on national mortality data. We extracted information on the antecedents of suicide of 544 of these 595 deaths (91%) from official investigations, mainly inquests. Results: Suicide-related online experience was reported in 24% (n = 128/544) of suicide deaths in young people between 2014 and 2016, equivalent to 43 deaths per year, and was more common in girls than boys (OR 1.87, 95% CI 1.23–2.85, p = 0.003) and those identifying as LGBT (OR 2.35, 95% CI 1.10–5.05, p = 0.028). Searching for information about method was most common (n = 68, 13%), followed by posting suicidal ideas online (n = 57, 10%). Self-harm, bereavement (especially by suicide), social isolation, and mental and physical ill-health were more likely in those known to have suicide-related online experience compared to those who did not. 29 (5%) were bullied online, more often girls (OR 2.84, 1.34–6.04, p = 0.007). Online bullying often accompanied face-to-face bullying (n = 16/29, 67%). Conclusions: Suicide-related online experience is a common, but likely underestimated, antecedent to suicide in young people. Although its causal role is unclear, it may influence suicidality in this population. Mental health professionals should be aware that suicide-related online experience – not limited to social media – is a potential risk for young patients, and may be linked to experiences offline. For public health, wider action is required on internet regulation and support for children and their families. [ABSTRACT FROM AUTHOR]