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Understanding the mineralogy and geochemistry of the subsurface is key when assessing and exploring for mineral deposits. To achieve this goal, rapid acquisition and accurate interpretation of drill core data are essential. Hyperspectral shortwave infrared imaging is a rapid and non-destructive analytical method widely used in the minerals industry to map minerals with diagnostic features in core samples. In this paper, we present an automated method to interpret hyperspectral shortwave infrared data on drill core to decipher major felsic rock-forming minerals using supervised machine learning techniques for processing, masking, and extracting mineralogical and textural information. This study utilizes a co-registered training dataset that integrates hyperspectral data with quantitative scanning electron microscopy data instead of spectrum matching using a spectral library. Our methodology overcomes previous limitations in hyperspectral data interpretation for the full mineralogy (i.e., quartz and feldspar) caused by the need to identify spectral features of minerals; in particular, it detects the presence of minerals that are considered invisible in traditional shortwave infrared hyperspectral analysis. [ABSTRACT FROM AUTHOR]

Background: Young people often face barriers to psychiatric care and are increasingly seeking crisis services for mental health issues through the emergency department (ED). Urgent psychiatric care models provide youth in crisis with rapid access to time‐limited mental health care on an outpatient basis. This scoping review aims to evaluate the impact of such urgent psychiatric services for youth aged 13–25 on patient and health system outcomes. Methods: We conducted a literature search on PubMed, EMBASE, MEDLINE, PsycINFO, and the Cochrane Database of Systematic Reviews for studies published from inception to November 20, 2020. We included studies that described outpatient psychiatric services designed for youth aged 13 to 25, took place in a clinical setting, and offered any combination of assessment, treatment, and referral. We excluded studies describing suicide intervention programmes. Results: Our search yielded six studies, four of which were descriptive studies and two of which were randomized controlled trials. Most studies found that access to urgent psychiatric care for youth was associated with reduced ED volumes, fewer health system costs, and fewer hospitalizations. None of the studies presented evidence that urgent psychiatric services are associated with improved patient symptomatology or functioning. Conclusions: The results of this scoping review highlight the scarcity of robust evidence evaluating the effectiveness of urgent care for youth mental health. Further experimental studies and a set of standardized quality measures for evaluating these services are needed to bridge this critical gap in mental health care for youth in crisis. [ABSTRACT FROM AUTHOR]

Organometal halide perovskite is a promising material in photovoltaic (PV) cells. Within a short time, its performance has increased dramatically to become a real competitor to silicon solar cells. Here we report on the temperature dependence (annealing temperature and the dependence of the photovoltaic parameters on temperature) of formamidinium (FA) lead iodide (FAPbI3), methylammonium (MA) lead iodide (MAPbI3) and their mixture (MAPbI3 : FAPbI3) in hole conductor free perovskite solar cells. These three types of perovskites function both as light harvesters and as hole conductors. Surface photovoltage and optical characterization reveal the p-type behavior and the band gap of the different perovskites. We observed that the ratio between the MA and FA cations might change during the annealing process, affecting the band gap and the stability of the layers. The PV parameters at different temperatures show better stability for the pure MAPbI3 and FAPbI3 solar cells compared to their mixture. Using intensity modulated photovoltage/photocurrent spectroscopy, we found that the diffusion length is weakly dependent on the light intensity, while the charge collection efficiency drops with light intensity for the FAPbI3-based cells. However, for MAPbI3 and the mixture, the charge collection efficiency remains constant for a wide range of light intensities. [ABSTRACT FROM AUTHOR]

Organo metal halide perovskite has attracted considerable attention recently due to its distinctive properties that make it especially useful in photovoltaic solar cells. In this work we demonstrate high open circuit voltage of 1.35 V using Al2O3/CH3NH3PbBr3 perovskite solar cells without a hole conductor. The contact potential difference under light measured by surface photovoltage spectroscopy of CH3NH3PbBr3 was more than twice that of CH3NH3PbI3, which results in smaller surface potential for the Al2O3/CH3NH3PbBr3 cells. Incident modulated photovoltage spectroscopy shows a longer recombination lifetime for the Al2O3/CH3NH3PbBr3 cells than for the TiO2/CH3NH3PbI3 cells or for the TiO2/CH3NH3PbBr3 cells, further supporting the high open circuit voltage. The possibility to gain high open circuit voltage even without a hole transport material in perovskite solar cells shows that the perovskite/metal oxide interface has a major effect on the open circuit voltage in perovskite based solar cells. [ABSTRACT FROM AUTHOR]

The limits of frequency resolution in nano-NMR experiments have been discussed extensively in recent years. It is believed that there is a crucial difference between the ability to resolve a few frequencies and the precision of estimating a single one. Whereas the efficiency of single frequency estimation gradually increases with the square root of the number of measurements, the ability to resolve two frequencies is limited by the specific timescale of the signal and cannot be compensated for by extra measurements. Here we show theoretically and demonstrate experimentally that the relationship between these quantities is more subtle and both are only limited by the Cramér-Rao bound of a single frequency estimation. [ABSTRACT FROM AUTHOR]

Engineering entanglement between quantum systems often involves coupling through a bosonic mediator, which should be disentangled from the systems at the operation's end. The quality of such an operation is generally limited by environmental and control noise. One of the prime techniques for suppressing noise is by dynamical decoupling, where one actively applies pulses at a rate that is faster than the typical time scale of the noise. However, for boson-mediated gates, current dynamical decoupling schemes require executing the pulses only when the boson and the quantum systems are disentangled. This restriction implies an increase of the gate time by a factor of √N, with N being the number of pulses applied. Here we propose and realize a method that enables dynamical decoupling in a boson-mediated system where the pulses can be applied while spin-boson entanglement persists, resulting in an increase in time that is at most a factor of π/2, independently of the number of pulses applied. We experimentally demonstrate the robustness of our entangling gate with fast dynamical decoupling to σz noise using ions in a Paul trap. [ABSTRACT FROM AUTHOR]

Cigarette smoking is very prevalent amongst patients suffering from mental disorders. In recent years additional scientific proof has been gathered regarding nicotine addiction mechanisms as effective treatments for smoking cessation. Some of these therapies are included in the "Basket of Health Services" of the State of Israel. Despite high smoking prevalence, the success rate for smoking cessation is low amongst patients with mental disorders. In this paper the possible reasons for this phenomenon are presented, as well as the possible biological and behavioral models that support this severe addiction amongst these patients. Scientifically based methods for smoking cessation are reviewed, including pharmacological and behavioral treatments. In addition, unique updated recommendations for smoking cessation amongst patients with mental disorders are presented.

Study Objective: To characterize the function and quality of sleep in patients with irritable bowel syndrome (IBS)., Design: A prospective study with a historic comparison group., Setting: A regional hospital that also serves as a tertiary referral center., Patients: Eighteen patients with IBS and a comparison group of 20 matched adults with mild benign snoring., Interventions: A polysomnography study and a wrist actigraphy study., Measurements: All subjects underwent sleep studies and completed self-report questionnaires (IBS severity, psychosocial variables, sleep function, and Epworth Sleepiness Scale). Fourteen IBS and 11 comparison patients underwent actigraphy., Results: The IBS patients had more than 70% less slow-wave stage sleep (4.5 +/- 7.3% vs 19.3 +/- 12.9%; P = 0.006), compensated by increased stage 2 sleep (72.2 +/- 6.6% vs 60.1 +/- 16.8%; P = 0.01). The IBS group had significant sleep fragmentation with a significantly higher arousal and awakening index (P < 0.001), a longer wake period after sleep onset (P = 0.02), and more downward shifts to lighter sleep stages (P = 0.01). The 4-night actigraphy study supported the polysomnography findings. The sleep fragmentation index was significantly higher (P = 0.008) in the IBS group. The IBS patients reported greater daytime sleepiness (9.0 +/- 4.8 vs 6.4 +/- 4.8, Epworth Sleepiness Scale score, P < 0.01) and greater impairment in quality of life, which correlated significantly with the sleep fragmentation indexes. The difference between the groups was not due to differences in baseline anxiety/depression levels., Conclusions: Patients with IBS have impaired sleep quality, reduced slow-wave sleep activity, and significant sleep fragmentation. The cause-and-effect relationship of these findings with patients' daytime symptoms should be studied further.