Miracle-dz/UniFAR-FTUs huggingface dataset:
Temperature dependence and screening models in quantum cascade structures

Different screening models in quantum cascade lasers are compared by calculating the contribution of intrasubband impurity scattering to the optical linewidth as a function of temperature. We find a strong impact of impurity scattering, which increases substantially with temperature. A simple isotropic bulk screening model works well if the screening length is of the order of or longer than the period length of the cascade structure.
Experimental Study on the Adhesion Strength of the Frozen Ice for Aircraft Moving Parts

At alpine regional airports, aircraft are covered with frozen ice when they encounter extreme weather such as heavy snow or frost. The movement parts of aircraft cabin doors, flaps and landing gear may be affected due to the infiltration of freezing ice, and the movement stagnation may occur when the the accumulation of ice is more serious. This paper sets up a mechanical performance test of frozen ice for this engineering problem to provide data that is beneficial to the selection of the mechanism drive and the determination of ice-breaking loads. The test is conducted based on the standard tensile shear test. In order to overcome problems such as the poor icing effect of the traditional specimen or the easy damage of the specimen ice, we improved the structure of the specimen and the method of the test. According to the characteristics of growth of frozen ice, we introduced freezing time, type of water quality and adhesion materials as test variables. The results show that: the ice adhesion strength of frozen ice increases and then decreases (−15 ∘C∼−55 ∘C). At the ambient temperature of −15 ∘C∼−55 ∘C and freezing for 2 h∼6 h, the ice adhesion strength of aluminum alloy surface ranges from 0.009 MPa to 0.568 MPa, and that of frozen ice on a silicone rubber surface is 0.005 MPa∼0.147 MPa. The duration of freezing did not significantly affect the adhesion strength of frozen ice. Among the three water qualities, the frozen ice from distilled water has the greatest adhesion strength, the lake water is the most medium, and the sea water is the smallest. The results of this test can be widely used in the determination of the ice-breaking load of civil aircraft, amphibious aircraft, ships, and the design of anti-ice/de-icing systems.
Audit of operation theater time utilization with perspective to optimize turnaround times and theater output

Background and Aims: Operation theater (OT) complex is an important area for a hospital as it needs expensive infrastructure, disposable, and reusable resources and a multidisciplinary highly qualified and efficient team, the metrics of which are key in generating revenue, and improved productivity. The efficient utilization of OT ensures maximum output in view of the investment of highly qualified doctors, equipment, and outcomes. Our study aimed to evaluate the utilization of OT functioning stepwise, reasons for delays, case cancellations, and areas of improvement if any. Material and Methods: This prospective observational study was planned in three phases; in phase 1 audit of OT functioning was carried out for 1 month and based on data analysis recommendations were given for improvement. In phase 2, the recommendations would be implemented over 3 months and in phase 3 re-audit will be carried out for 1 month. Data analysis was done on IBM SPSS version 26 software. Descriptive statistics measures were calculated by the mean and standard deviation. Results: The total available resource time was 52920 min and the total time utilized was 37740 min. Overall, raw utilization was 71.31%. OT was started late 63.50% times. Case cancellation occurred on 8.99% occasions. Conclusion: We conclude that utilization of operating room time can be maximized by proper planning and realistic scheduling of elective lists, communication among team members, and resource management. Audit of OT utilization is an important tool to identify problem areas and formulate protocols accordingly.
The RMS survey - 6 cm continuum VLA observations towards candidate massive YSOs in the northern hemisphere

Context. The Red MSX Source (RMS) survey is an ongoing multi-wavelength observational programme designed to return a large, well-selected sample of massive young stellar objects (MYSOs). We have identified ∼2000 MYSO candidates located throughout the Galaxy by comparing the colours of MSX and 2MASS point sources to those of known MYSOs. The aim of these follow-up observations is to identify other objects with similar colours such as ultra compact (UC) HII regions, evolved stars and planetary nebulae (PNe) and distinguish between genuine MYSOs and nearby low-mass YSOs. Aims. To identify the populations of UCHII regions and PNe within the sample and examine their Galactic distribution. Methods. We have conducted high resolution radio continuum observations at 6 cm towards 659 MYSO candidates in the northern hemisphere (10 ◦ < l < 250 ◦ ) using the Very Large Array (VLA). These observations have a spatial resolution of ∼1–2 �� and typical image rms noise values of ∼0.22 mJy – sensitive enough to detect a HII region powered by B0.5 star at the far side of the Galaxy. In addition to these targeted observations we present archival data towards a further 315 RMS sources extracted from a previous VLA survey of the inner Galaxy. Results. We present the results of radio continuum observations made towards 974 MYSO candidates, 272 (∼27% of the observed sample) of which are found to be associated with radio emission above a 4σ detection limit (∼1 mJy). Using results from other parts of our multi-wavelength survey we separate these RMS-radio associations into two distinct types of objects, classifying 51 as PNe and a further 208 as either compact or UC HII regions. Including all HII regions and PNe identified either from the literature or from the multi-wavelength data these numbers increase to 391 and 79, respectively. Using this well selected sample of HII regions we estimate their Galactic scale height to be 0.6 ◦ . In addition to the RMS-radio associations we are able to set upper limits on the radio emission of ≤1 mJy for the 702 non-detections, which is below the level expected if they had already begun to ionise their surroundings. Conclusions. Using radio continuum and archival data we have identified 79 PNe and 391 HII regions within the northern RMS catalogue. We estimate the total fraction of contamination by PNe in the RMS sample is of order 10%. The sample of HII regions is probably the best representation to date of the Galactic population of HII regions as a whole.
Nonprofit Scandals: A Systematic Review and Conceptual Framework

High-profile charity scandals have always represented a threat to the nonprofit sector, which relies on public trust and funding to operate. We systematically review 30 years of empirical research on scandals involving nonprofits and present both quantitative and qualitative syntheses of the 71 articles identified. Informed by this review, we generate a conceptual model theorizing the causes and consequences of scandals, as well as how nonprofits can best prevent and respond to organizational transgressions. We then put forward a research agenda that elaborates five key factors that are especially important for understanding nonprofit scandals but remain understudied: (a) integrity versus competence violations, (b) moral licensing, (c) the multilevel nature of organizational transgressions, (d) sectoral causes of scandal, and (e) effective responses. We close the article with recommendations for nonprofit managers about how to conceptualize, prevent, plan for, and respond to transgressions occurring within their organizations, and any resulting scandals.
A DENSITY-INDEPENDENT FORMULATION OF SMOOTHED PARTICLE HYDRODYNAMICS

The standard formulation of the smoothed particle hydrodynamics (SPH) assumes that the local density distribution is differentiable. This assumption is used to derive the spatial derivatives of other quantities. However, this assumption breaks down at the contact discontinuity. At the contact discontinuity, the density of the low-density side is overestimated while that of the high-density side is underestimated. As a result, the pressure of the low-density (high-density) side is overestimated (underestimated). Thus, unphysical repulsive force appears at the contact discontinuity, resulting in the effective surface tension. This tension suppresses fluid instabilities. In this paper, we present a new formulation of SPH, which does not require the differentiability of density. Instead of the mass density, we adopt the internal energy density (pressure) and its arbitrary function, which are smoothed quantities at the contact discontinuity, as the volume element used for the kernel integration. We call this new formulation density-independent SPH (DISPH). It handles the contact discontinuity without numerical problems. The results of standard tests such as the shock tube, Kelvin–Helmholtz and Rayleigh–Taylor instabilities, point-like explosion, and blob tests are all very favorable to DISPH. We conclude that DISPH solved most of the known difficulties of the standard SPH, without introducing additional numerical diffusion or breaking the exact force symmetry or energy conservation. Our new SPH includes the formulation proposed by Ritchie & Thomas as a special case. Our formulation can be extended to handle a non-ideal gas easily.
High-Frequency Transcranial Random Noise Stimulation Modulates Gamma-Band EEG Source-Based Large-Scale Functional Network Connectivity in Patients with Schizophrenia: A Randomized, Double-Blind, Sham-Controlled Clinical Trial

Schizophrenia is associated with increased resting-state large-scale functional network connectivity in the gamma frequency. High-frequency transcranial random noise stimulation (hf-tRNS) modulates gamma-band endogenous neural oscillations in healthy individuals through the application of low-amplitude electrical noises. Yet, it is unclear if hf-tRNS can modulate gamma-band functional connectivity in patients with schizophrenia. We performed a randomized, double-blind, sham-controlled clinical trial to contrast hf-tRNS (N = 17) and sham stimulation (N = 18) for treating negative symptoms in 35 schizophrenia patients. Short continuous currents without neuromodulatory effects were applied in the sham group to mimic real-stimulation sensations. We used electroencephalography to investigate if a five-day, twice-daily hf-tRNS protocol modulates gamma-band (33–45 Hz) functional network connectivity in schizophrenia. Exact low resolution electromagnetic tomography (eLORETA) was used to compute intra-cortical activity from regions within the default mode network (DMN) and fronto-parietal network (FPN), and functional connectivity was computed using lagged phase synchronization. We found that hf-tRNS reduced gamma-band within-DMN and within-FPN connectivity at the end of stimulation relative to sham stimulation. A trend was obtained between the change in within-FPN functional connectivity from baseline to the end of stimulation and the improvement of negative symptoms at the one-month follow-up (r = −0.49, p = 0.055). Together, our findings suggest that hf-tRNS has potential as a network-level approach to modulate large-scale functional network connectivity pertaining to negative symptoms of schizophrenia.
Study of Single Nucleotide Polymorphisms Associated with Breast Cancer Patients among Arab Ancestries

The aim of this study is to investigate the single nucleotide polymorphisms (SNPs) associated with breast cancer in our population of Arab patients. We investigated 26 breast cancer patients and an equal number of healthy age- and sex-matched control volunteers. We examined the exome wide microarray-based biomarkers and screened 243,345 SNPs for their possible significant association with our breast cancer patients. Successfully, we identified the most significant (p value ≤9.14 × 10−09) four associated SNPs [SNRK and SNRK-AS1-rs202018563G; BRCA2-rs2227943C; ZNF484-rs199826847C; and DCPS-rs1695739G] among persons with breast cancer versus the healthy controls even after Bonferroni corrections (p value <2.05 × 10−07). Although our patients' numbers were limited, the identified SNPs might shed some light on certain breast cancer-associated functional multigenic variations in Arab patients. We assert on the importance of more extensive large-scale analysis to confirm the candidate biomarkers and possible target genes of breast cancer among Arab ancestries.
An Integral View of Balmer-dominated Shocks in Supernova Remnants

Abstract We present integral-field spectroscopic observations with the VIMOS-IFU at the VLT of fast (2000-3000 kms−1) Balmer-dominated shocks surrounding the northwestern rim of the remnant of supernova 1006. The high spatial and spectral resolution of the instrument enable us to show that the physical characteristics of the shocks exhibit a strong spatial variation over few atomic scale lengths across 133 sky locations. Our results point to the presence of a population of non-thermal protons (10-100 keV) which might well be the seed particles for generating high-energy cosmic rays. We also present observations of Tycho's supernova remnant taken with the narrow-band tunable filter imager OSIRIS at the GTC and the Fabry-Perot interferometer GHaFaS at the WHT to resolve respectively the broad and narrow Hα lines across a large part of the remnant.
Deep Learning and 5G and Beyond for Child Drowning Prevention in Swimming Pools

Drowning is a major health issue worldwide. The World Health Organization’s global report on drowning states that the highest rates of drowning deaths occur among children aged 1–4 years, followed by children aged 5–9 years. Young children can drown silently in as little as 25 s, even in the shallow end or in a baby pool. The report also identifies that the main risk factor for children drowning is the lack of or inadequate supervision. Therefore, in this paper, we propose a novel 5G and beyond child drowning prevention system based on deep learning that detects and classifies distractions of inattentive parents or caregivers and alerts them to focus on active child supervision in swimming pools. In this proposal, we have generated our own dataset, which consists of images of parents/caregivers watching the children or being distracted. The proposed model can successfully perform a seven-class classification with very high accuracies (98%, 94%, and 90% for each model, respectively). ResNet-50, compared with the other models, performs better classifications for most classes.
Novel systems and techniques for nonlinear optics at low light levels

This thesis describes novel experimental approaches to nonlinear optics at low light levels. These approaches focus on significantly increasing the probability of interaction between two weak pulses of light by using novel photonic systems and quantum control techniques. Specifically, the creation of a stationary pulse of light with non-vanishing photonic component was experimentally demonstrated. Our technique allows a pulse of light to enter into, be stopped inside, and finally be released from a room temperature coherently controlled atomic ensemble, which is dynamically and reversibly turned into a cavity-like system in the process. A detailed theoretical description of the phenomena is presented in addition to the experimental results that show pulses of light kept stationary for up to several microseconds. We also describe a technique for loading laser-cooled atoms into a single-mode hollow-core photonic-crystal fiber.In our approach, atoms collected in a magnetooptical trap are transferred into a dipole optical trap guided by such fiber. This trap confines the atoms inside the 7 μm diameter hollow core of this fiber for time scales on the order of tens of milliseconds. We observe atomic ensembles consisting of as few as 200 atoms creating an optically thick medium when confined inside the hollow-core fiber. We report the loading of up to 30000 rubidium atoms into this fiber, which results in a system with optical depth 150. Finally, we demonstrate a fiber-optical switch that is activated at tiny energies corresponding to a few hundred optical photons per pulse. This is achieved by simultaneously confining both photons and a small ensemble of cold atoms inside the microscopic hollow core of a single-mode photonic-crystal fiber and using techniques from quantum optics resulting in slow light propagation and large nonlinear interaction between light beams.
Effects of a computer-based enrichment programme on the development of analytical and creative abilities in gifted students

Abstract Enrichment programmes are designed to offer gifted students experiences that are not covered in the regular curriculum We used a pre-test–post-test control group design to examine the effects of a computer-based enrichment programme on the development of analytical and creative abilities in 26 gifted children in an experimental group (15 boys, mean age = 10 years and 3 months) and compared this to 20 equally gifted children in a control group (8 boys, mean age = 10 years and 4 months). Students were identified as being analytically gifted, creatively gifted, or analytically-creatively gifted. In general, results showed increasing levels of analytical ability and stable levels of creative ability. In addition, hierarchical regression analyses showed a positive effect of the enrichment programme on the development of analytical abilities in children with relatively low starting levels of analytical ability (i.e. the creatively gifted students). To conclude, results suggest that rather than analytically gifted children, children with creative talents gained most advantage from participating in the computer-based enrichment programme.
Prognostic Nomogram for Postoperative Hypopharyngeal Squamous Cell Carcinoma to Assist Decision Making for Adjuvant Chemotherapy

We aimed to investigate the effect of lymph node parameters on postoperative hypopharyngeal squamous cell carcinoma (HSCC) and to establish a nomogram to predict its prognosis and assist in adjuvant chemotherapy decisions. A retrospective analysis of postoperative HSCC in the Surveillance, Epidemiology, and End Results database (2004–2019) was performed. Cutoff points for continuous variables were determined by X-tile software. Univariate and multivariate analyses were performed to identify prognostic factors on overall survival (OS), and these variables were used to construct a nomogram. The nomogram’s accuracy was internally validated using concordance index, area under the curve, calibration plot, and decision curve analyses. Furthermore, the value of chemotherapy in each risk subgroup was assessed separately based on individualized scores from the nomogram. In total, 404 patients were eligible for analysis, and the median OS was 39 months. Age, origin, primary site, T stage, number of lymph nodes examined, lymph node ratio, and radiotherapy were identified as prognostic factors for OS and incorporated into the nomogram. In both the training and validation cohorts, favorable performance was exhibited compared with the other stage systems, and patients could be classified into low-, intermediate-, and high-risk subgroups. Chemotherapy significantly improved the OS in the high-risk subgroup, whereas chemotherapy did not confer a survival benefit in the low- or intermediate-risk groups. The lymph node parameter-based nomogram model can better stratify the prognosis of HSCC patients and screen out patients who would benefit from chemotherapy, suggesting that the model could be used as a reference for clinical decision making and to avoid overtreatment.
Lessons learned from a peer support program for individuals seeking substance use recovery

Abstract Peer navigation is a model that includes connecting an individual in need of services with a peer who can navigate engagement in clinical treatment services and provide emotional and logistical support that is often unavailable through the traditional system. In the substance use field—where the use of peers is a relatively new phenomenon—peers are individuals with lived experiences who are in recovery themselves. In 2016, a peer program called RECOVERY was implemented in a northeastern U.S. state. This team of peers act as a bridge between a referral source (e.g., police, emergency services, hospital) and treatment facilities. Using semi-structured interviews from the team of peers (N = 5), this paper provides a case study of the implementation process for this peer recovery program. The findings identify potential barriers and facilitators to peer services and offer a feasible approach for implementing peer support programs in substance use settings.
EVOLUTION OF PRIMORDIAL STARS POWERED BY DARK MATTER ANNIHILATION UP TO THE MAIN-SEQUENCE STAGE

Primordial stars formed in the early universe are thought to be hosted by compact dark matter (DM) halos. If DM consists of weakly interacting massive particles (WIMPs), such stars may be powered by DM annihilation during the early phases of their evolution. We study the pre-main-sequence evolution of the primordial star using a detailed stellar evolution code under the assumption that the annihilation of adiabatically contracted WIMP DM within the star provides sufficient energy to sustain the stellar equilibrium. We follow the evolution of accreting stars using several gas mass accretion rates derived from cosmological simulations. We show that the stellar mass becomes very large, up to 900–1000 M☉ when the star reaches the main-sequence phase for a reasonable set of model parameters such as DM particle mass and the annihilation cross section. During the dark star phase, the star expands by over a thousand solar radii, while the surface temperature remains below 104 K. The energy generated by nuclear reactions is not dominant during this phase. We also study models with different gas mass accretion rates and the DM particle masses. All our models for different DM particle masses pass the dark star phase. The final mass of the dark stars is essentially unchanged for DM mass of mχ ⩽ 10 GeV. Gravitational collapse of the massive dark stars will leave massive black holes with mass as large as 1000 M☉ in the early universe.