Automated detection and mapping of crystal tilt using thermal diffuse scattering in transmission electron microscopy.

Quantitative interpretation of transmission electron microscopy (TEM) data of crystalline specimens often requires the accurate knowledge of the local crystal orientation. A method is presented which exploits momentum-resolved scanning TEM (STEM) data to determine the local mistilt from a major zone axis. It is based on a geometric analysis of Kikuchi bands within a single diffraction pattern, yielding the center of the Laue circle.

On the electrocatalytical oxygen reduction reaction activity and stability of quaternary RhMo-doped PtNi/C octahedral nanocrystals.

Recently proposed bimetallic octahedral Pt-Ni electrocatalysts for the oxygen reduction reaction (ORR) in proton exchange membrane fuel cell (PEMFC) cathodes suffer from particle instabilities in the form of Ni corrosion and shape degradation. Advanced trimetallic Pt-based electrocatalysts have contributed to their catalytic performance and stability. In this work, we propose and analyse a novel quaternary octahedral (oh-)Pt nanoalloy concept with two distinct metals serving as stabilizing surface dopants.

Characteristics of dementia family caregivers who use paid professional in-home respite care.

Caring for a person living with dementia (PLWD) can be challenging, making support services like respite important. Of the types of respite, research on paid professional in-home care specific to family caregivers of PLWD is limited. This study aimed to identify characteristics of dementia caregivers using paid in-home respite.

Highly Active and Stable Large Mo-Doped Pt-Ni Octahedral Catalysts for ORR: Synthesis, Post-treatments, and Electrochemical Performance and Stability.

Over the past decade, advances in the colloidal syntheses of octahedral-shaped Pt-Ni alloy nanocatalysts for use in fuel cell cathodes have raised our atomic-scale control of particle morphology and surface composition, which, in turn, helped raise their catalytic activity far above that of benchmark Pt catalysts. Future fuel cell deployment in heavy-duty vehicles caused the scientific priorities to shift from alloy particle activity to stability. Larger particles generally offer enhanced thermodynamic stability, yet synthetic approaches toward larger octahedral Pt-Ni alloy nanoparticles have remained elusive.

Systematic Review of Technical Variations for Mohs Micrographic Surgery for Melanoma.

Background: Mohs micrographic surgery (MMS) for cutaneous melanoma is becoming more prevalent, but surgical technique varies.

Objective: To define variations in published techniques for MMS for melanoma.

Methods And Materials: A systematic review was performed of PubMed, EMBASE, and Scopus databases to identify all articles describing surgical techniques for MMS for melanoma.

Student Perceptions of a Reflective Writing-based Wellness Course: "Good in Theory, But...".

To offset disconcerting trends showing alarming rates of burnout and other types of psychological distress among medical students, many medical schools have implemented wellness initiatives for first year students as they are first adjusting to the rigors of medical school. This study examines students' attitudes toward a reflective writing-based wellness course. We conducted a thematic analysis of 97 writings that students wrote in response to a prompt asking them what they thought of the wellness course at an American Midwestern medical school.

The direct and indirect effects of clinical empathy on well-being among pre-medical students: a structural equation model approach.

Background: Empathy is a well-established facet of clinical competency that research suggests is associated with enhanced medical student well-being. Since little is known about empathy and well-being before students enter medical school-during pre-medical education-the main goal of this study is to test a conceptual model of how clinical empathy is related to two indicators of well-being, depression, and burnout among pre-medical students. The theoretical model hypothesizes that three dimensions of clinical empathy-Perspective-Taking, Compassionate Care, and Standing in Patients' Shoes- will be directly and negatively related to depression, as well as indirectly through its inverse relationship with three facets of burnout, Emotional Exhaustion, Poor Academic Efficacy, and Cynicism.

Compliance with sentinel lymph node biopsy guidelines for invasive melanomas treated with Mohs micrographic surgery.

Background: Sentinel lymph node biopsy (SLNB) has not been studied for invasive melanomas treated with Mohs micrographic surgery using frozen-section MART-1 immunohistochemical stains (MMS-IHC). The primary objective of this study was to assess the accuracy and compliance with National Comprehensive Cancer Network (NCCN) guidelines for SLNB in a cohort of patients who had invasive melanoma treated with MMS-IHC.

Methods: This retrospective cohort study included all patients who had primary, invasive, cutaneous melanomas treated with MMS-IHC at a single academic center between March 2006 and April 2018.

Combining quantitative ADF STEM with SiN membrane-based MEMS devices: A simulation study with Pt nanoparticles.

Computer simulations are used to assess the influence of a 20-nm-thick SiN membrane on the quantification of atomic-resolution annular dark-field (ADF) scanning transmission electron microscopy images of Pt nanoparticles. The discussions include the effect of different nanoparticle/membrane arrangements, accelerating voltage, nanoparticle thickness and the presence of adjacent atomic columns on the accuracy with which the number of Pt atoms in each atom column can be counted. The results, which are based on the use of ADF scattering cross-sections, show that an accuracy of better than a single atom is attainable at 200 and 300 kV.

Optimizing Experimental Conditions for Accurate Quantitative Energy-Dispersive X-ray Analysis of Interfaces at the Atomic Scale.

The invention of silicon drift detectors has resulted in an unprecedented improvement in detection efficiency for energy-dispersive X-ray (EDX) spectroscopy in the scanning transmission electron microscope. The result is numerous beautiful atomic-scale maps, which provide insights into the internal structure of a variety of materials. However, the task still remains to understand exactly where the X-ray signal comes from and how accurately it can be quantified.

Association Between Surgical Margins Larger Than 1 cm and Overall Survival in Patients With Merkel Cell Carcinoma.

Importance: Current recommendations regarding the size of local excision (LE) margins for Merkel cell carcinoma (MCC) have not been well established.

Objective: To assess whether larger clinical LE margins and receipt of adjuvant radiotherapy are associated with improvements in overall survival (OS) among patients with localized MCC.

Design, Setting, And Participants: This large multicenter retrospective cohort study used records from the National Cancer Database to identify adult patients with localized stage I or stage II MCC who underwent LE between January 1, 2004, and December 31, 2015.

Extraction of 3D quantitative maps using EDS-STEM tomography and HAADF-EDS bimodal tomography.

Electron tomography has been widely applied to three-dimensional (3D) morphology characterization and chemical analysis at the nanoscale. A HAADF-EDS bimodal tomographic (HEBT) reconstruction technique has been developed to extract high resolution element-specific information. However, the reconstructed elemental maps cannot be directly converted to quantitative compositional information.

Simultaneous Photonic and Excitonic Coupling in Spherical Quantum Dot Supercrystals.

Semiconductor nanocrystals, or quantum dots (QDs), simultaneously benefit from inexpensive low-temperature solution processing and exciting photophysics, making them the ideal candidates for next-generation solar cells and photodetectors. While the working principles of these devices rely on light absorption, QDs intrinsically belong to the Rayleigh regime and display optical behavior limited to electric dipole resonances, resulting in low absorption efficiencies. Increasing the absorption efficiency of QDs, together with their electronic and excitonic coupling to enhance charge carrier mobility, is therefore of critical importance to enable practical applications.

"From All Walks of Life": Attending an Alcoholics Anonymous Meeting to Reduce Addiction Stigma Among Medical Students.

Objective: Substance use disorders (SUDs) are stigmatized conditions in medicine, with negative attitudes toward patients with SUDs beginning to form in medical school. Only a few studies with small samples show that attending an Alcoholics Anonymous (AA) meeting may help decrease addiction stigma. This study examined whether attending an AA meeting impacts medical student attitudes toward patients with SUDs and any gender and age group differences within these attitudes.

False-positive pregnancy test secondary to ectopic expression of human chorionic gonadotropin by a gastrointestinal stromal tumor.

Tumors can rarely overexpress human chorionic gonadotropin (hCG) resulting in false-positive pregnancy tests. Here, we report a 44-year-old female with a metastatic gastrointestinal stromal tumor (GIST) who presented with a positive urine pregnancy test before radiotherapy. Further workup ruled out pregnancy.

Management of primary skin cancer during a pandemic: Multidisciplinary recommendations.

During the coronavirus disease 2019 (COVID-19) pandemic, providers and patients must engage in shared decision making regarding the pros and cons of early versus delayed interventions for localized skin cancer. Patients at highest risk of COVID-19 complications are older; are immunosuppressed; and have diabetes, cancer, or cardiopulmonary disease, with multiple comorbidities associated with worse outcomes. Physicians must weigh the patient's risk of COVID-19 complications in the event of exposure against the risk of worse oncologic outcomes from delaying cancer therapy.

Pilot Study of a Novel Therapeutic Approach for Refractory Advanced Stage Folliculotropic Mycosis Fungoides.

Folliculotropic mycosis fungoides is a variant of cutaneous T-cell lymphoma characterized as having a folliculocentric infiltrate of malignant T cells along with a worse prognosis in comparison to the epidermotropic variants. Patients with advanced forms of folliculotropic mycosis fungoides are often poorly responsive to both skin-directed as well as to systemic therapies. We report here a high response rate using a novel therapeutic regimen combining interferon gamma, isotretinoin in low dose and topical carmustine, and in some cases concomitant skin-directed therapies, among 6 consecutive patients with refractory folliculotropic mycosis fungoides with stages IB through IIIB who had previously failed both topical and systemic therapies.

Diagnosis of Obstructive Sleep Apnea during Wakefulness Using Upper Airway Negative Pressure and Machine Learning.

Background and Rational: Obstructive Sleep Apnea (OSA) is a common disorder, affecting almost 10% of adults, but very underdiagnosed. This is largely due to limited access to overnight sleep testing using polysomnography (PSG). Our goal was to distinguish OSA from healthy individual using a simple maneuver during wakefulness in combination with machine learning methods.

Multi-modal and multi-scale non-local means method to analyze spectroscopic datasets.

A multi-modal and multi-scale non-local means (M3S-NLM) method is proposed to extract atomically resolved spectroscopic maps from low signal-to-noise (SNR) datasets recorded with a transmission electron microscope. This method improves upon previously tested denoising techniques as it takes into account the correlation between the dark-field signal recorded simultaneously with the spectroscopic dataset without compromising on the spatial resolution. The M3S-NLM method was applied to electron energy dispersive X-ray and electron-energy-loss spectroscopy (EELS) datasets.

Dissociation between objectively quantified snoring and sleep quality.

Background: The impact of simple snoring on sleep structure and sleepiness has not been well described. In several studies, self-reported snoring was associated with increased daytime sleepiness. However, most studies did not distinguish patients with simple snoring from those with coexisting obstructive sleep apnea (OSA) using objective measures.