Illuminating Massive Black Holes With White Dwarfs: Orbital Dynamics and High Energy Transients from Tidal Interactions

White dwarfs (WDs) can be tidally disrupted only by massive black holes (MBHs) with masses less than $\sim10^5 M_\odot$. These tidal interactions feed material to the MBH well above its Eddington limit, with the potential to launch a relativistic jet. The corresponding beamed emission is a promising signpost to an otherwise quiescent MBH of relatively low mass. We show that the mass transfer history, and thus the lightcurve, are quite different when the disruptive orbit is parabolic, eccentric, or circular. The mass lost each orbit exponentiates in the eccentric-orbit case leading to the destruction of the WD after several tens of orbits. We examine the stellar dynamics of clusters surrounding MBHs to show that single-passage WD disruptions are substantially more common than repeating encounters. The $10^{49}$ erg s$^{-1}$ peak luminosity of these events makes them visible to cosmological distances. They may be detectible at rates of as many as tens per year by instruments like Swift. In fact, WD-disruption transients significantly outshine their main-sequence star counterparts, and are the most likely tidal interaction to be detected arising from MBHs with masses less than $10^5 M_\odot$. The detection or non-detection of such WD-disruption transients by Swift is, therefore, a powerful tool to constrain lower end of the MBH mass function. The emerging class of ultra-long gamma ray bursts all have peak luminosities and durations reminiscent of WD disruptions, offering a hint that WD-disruption transients may already be present in existing datasets.Comment: Revised following response from refere

The Jewish Museum of Florida-FIU: Archives on the Edge

As the COVID-19 pandemic has threatened much of our access to communal spaces of learning and research such as universities, libraries, and museum collections, many new technologies have emerged to make these resources accessible to the public from the comfort of their homes. The Jewish Museum of Florida-FIU (JMOF) collection consists of ~60,000 objects, documents, images and ephemera. The collections are wide-ranging in content, cover numerous subject headings and geographically represent all sixty-seven counties of Florida and Cuba. Join the JMOF staff for a series of lightning talks with Registrar Todd Bothel, Curator Jacqueline Goldstein, and Education Manager Luna Goldberg. Topics will include a briefing about the museum’s holdings and ongoing digitization process, new technologies we have implemented to present virtual reality exhibitions to the public, as well as a discussion on virtual resources that have contributed to successful education and outreach programs across Florida and the country at-large

A Characterization of Cancer Patients in Inpatient Rehabilitation Facilities: A Retrospective Cohort Study

OBJECTIVES: To identify the types of cancer patients admitted to inpatient medical rehabilitation and to describe their rehabilitation outcomes. DESIGN: Retrospective cohort study. SETTING: U.S. inpatient rehabilitation facilities (IRFs). PARTICIPANTS: Adult patients (N=27,952) with a malignant cancer diagnosis admitted to an IRF with a cancer-related impairment between October 2010 and September 2012 were identified from the Uniform Data System for Medical Rehabilitation database. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Demographic, medical, and rehabilitation characteristics for patients with various cancer tumor types were summarized using data collected from the Inpatient Rehabilitation Facility-Patient Assessment Instrument. Rehabilitation outcomes included the percentage of patients discharged to the community and acute care settings, and functional change from admission to discharge. Functional status was measured using the FIM instrument. RESULTS: Cancer patients constituted about 2.4% of the total IRF patient population. Cancer types included brain and nervous system (52.9%), digestive (12.0%), bone and joint (8.7%), blood and lymphatic (7.6%), respiratory (7.1%), and other (11.7%). Overall, 72% were discharged to a community setting, and 16.5% were discharged back to acute care. Patients with blood and lymphatic cancers had the highest frequency of discharge back to acute care (28%). On average, all cancer patient groups made significant functional gains during their IRF stay (mean FIM total change ± SD, 23.5±16.2). CONCLUSIONS: In a database representing approximately 70% of all U.S. patients in IRFs, we found that patients with a variety of cancer types are admitted to inpatient rehabilitation. Most cancer patients admitted to IRFs were discharged to a community setting and, on average, improved their function. Future research is warranted to understand the referral patterns of admission to postacute care rehabilitation and to identify factors that are associated with rehabilitation benefit in order to inform the establishment of appropriate care protocols

Non-Invasive Raman Tomographic Imaging of Canine Bone Tissue

Raman spectroscopic diffuse tomographic imaging has been demonstrated for the first time. It provides a noninvasive, label-free modality to image the chemical composition of human and animal tissue and other turbid media. This technique has been applied to image the composition of bone tissue within an intact section of a canine limb. Spatially distributed 785-nm laser excitation was employed to prevent thermal damage to the tissue. Diffuse emission tomography reconstruction was used, and the location that was recovered has been confirmed by micro-computed tomography (micro-CT) images. With recent advances, diffuse tomography shows promise for in vivo clinical imaging.1, 2 In principle, algorithms developed for fluorescence imaging in tissue can be applied to Raman signals. Although the Raman effect is weaker than fluorescence, the scattered signal is detectable, and thus tomography is achievable. Here we demonstrate the first diffuse tomography reconstructions based on Raman scatter. Raman mapping and imaging are well-established techniques for examining material surfaces.3 Subsurface mapping of simple planar objects was reported recently4, 5 using fiber optic probes with spatially separated injection and collection fibers.6 Noninvasive measurements of bone Raman spectra were demonstrated at depths of5mm role= presentation \u3e5mm below the skin.5 Bone is promising for Raman tomography because the spectra are rich in compositional information,7 which reflects bone maturity and health. Spectroscopically measured bone composition changes have been correlated with aging8 and susceptibility to osteoporotic fracture.9 The Raman spectrum of bone mineral is easily distinguished from the spectra of proteins and other organic tissue constituents, facilitating recovery of even weak signals by multivariate techniques. Assessments of bone quantity and quality are essential to detect and monitor fracture risk and fracture healing with disease or injury. Common sites for fracture with osteoporosis are the spine, proximal femur, and distal radius. Stress fractures are most frequently seen in the weight-bearing sites of the tibia and metatarsals. Fracture risk depends on bone geometry, architecture, and material properties, as well as the nature of applied load (magnitude, rate, and direction). As a result, noninvasive imaging and nondestructive analysis methods have been developed to assess many of these bone attributes that are increasingly important to clinical practice and basic research in orthopedics.10 Current clinical in vivo methods include dual-energy x-ray absorptiometry (DXA), quantitative computed tomography (QCT), magnetic resonance imaging (MRI), ultrasound, and most recently, high-resolution peripheral QCT. Ex vivo analyses of bone specimens from patients or animals have also utilized these and other techniques. In this study, we couple micro-computed tomography (micro-CT) and diffuse optical tomography with Raman spectroscopy to recover spatial and composition information from bone tissue ex vivo. We demonstrate the first reconstruction-based recovery of Raman signals through thick tissues to yield molecular information about subsurface bone tissue. Reconstructions from transcutaneous Raman measurements are challenging, because layers of skin, muscle, fat, and connective tissue lie over the bone sites of interest. These layers have different optical properties and thus variably scatter and polarize the injected light. We chose a canine model because of specimen availability and a bone size similar to human bone. We selected the tibia, a site that is clinically important and has relatively few overlying soft tissues. Measurements were made on the medial surface, where the only additional optical barrier is the crural extensor retinaculum ligament. The canine hind limb was harvested from an animal euthanized in an approved (UCUCA) University of Michigan study. The section of the limb distal to the knee was excised and scanned using in vivo micro-CT (eXplore Locus RS, GE Healthcare, Ontario, Canada). The tibia was scanned at80kV role= presentation \u3e80kV and 450μA role= presentation \u3e450μA with an exposure time of 100ms role= presentation \u3e100ms using a 360-deg scan technique. The image was reconstructed at a 93-μm role= presentation \u3e93-μm voxel resolution [Fig. 1a ]

Functional status predicts acute care readmissions from inpatient rehabilitation in the stroke population

Objective: Acute care readmission risk is an increasingly recognized problem that has garnered significant attention, yet the reasons for acute care readmission in the inpatient rehabilitation population are complex and likely multifactorial. Information on both medical comorbidities and functional status is routinely collected for stroke patients participating in inpatient rehabilitation. We sought to determine whether functional status is a more robust predictor of acute care readmissions in the inpatient rehabilitation stroke population compared with medical comorbidities using a large, administrative data set. Methods: A retrospective analysis of data from the Uniform Data System for Medical Rehabilitation from the years 2002 to 2011 was performed examining stroke patients admitted to inpatient rehabilitation facilities. A Basic Model for predicting acute care readmission risk based on age and functional status was compared with models incorporating functional status and medical comorbidities (Basic-Plus) or models including age and medical comorbidities alone (Age-Comorbidity). C-statistics were compared to evaluate model performance. Findings: There were a total of 803,124 patients: 88,187 (11%) patients were transferred back to an acute hospital: 22,247 (2.8%) within 3 days, 43,481 (5.4%) within 7 days, and 85,431 (10.6%) within 30 days. The C-statistics for the Basic Model were 0.701, 0.672, and 0.682 at days 3, 7, and 30 respectively. As compared to the Basic Model, the best-performing Basic-Plus model was the Basic+Elixhauser model with C-statistics differences of +0.011, +0.011, and + 0.012, and the best-performing Age-Comorbidity model was the Age+Elixhauser model with C-statistic differences of -0.124, -0.098, and -0.098 at days 3, 7, and 30 respectively. Conclusions: Readmission models for the inpatient rehabilitation stroke population based on functional status and age showed better predictive ability than models based on medical comorbidities

Patient Perspectives on Tobacco Use Treatment in Primary Care

IntroductionEvidence-based tobacco cessation interventions increase quit rates, yet most smokers do not use them. Every primary care visit offers the potential to discuss such options, but communication can be tricky for patients and provider alike. We explored smokers’ personal interactions with health care providers to better understand what it is like to be a smoker in an increasingly smoke-free era and the resources needed to support quit attempts and to better define important patient-centered outcomes.MethodsThree 90-minute focus groups, involving 33 patients from 3 primary care clinics, were conducted. Participants were current or recent (having quit within 6 months) smokers. Topics included tobacco use, quit attempts, and interactions with providers, followed by more pointed questions exploring actions patients want from providers and outcome measures that would be meaningful to patients.ResultsFour themes were identified through inductive coding techniques: 1) the experience of being a tobacco user (inconvenience, shame, isolation, risks, and benefits), 2) the medical encounter (expectations of providers, trust and respect, and positive, targeted messaging), 3) high-value actions (consistent dialogue, the addiction model, point-of-care nicotine patches, educational materials, carbon monoxide monitoring, and infrastructure), and 4) patient-centered outcomes.ConclusionEngaged patient-centered smoking cessation counseling requires seeking the patient voice early in the process. Participants desired honest, consistent, and pro-active discussions and actions. Participants also suggested creative patient-centered outcome measures to consider in future research

Advanced cancer patient preferences for receiving molecular profiling results

Objective: This study aimed to discern preferences for receiving somatic molecular profiling (MP) results in cancer patients who have given consent to undergo testing. Methods: We conducted a mixed‐methods study to explore patients’ views on which MP results they would like to receive and why. Advanced cancer patients (n=1299) completed questionnaires after giving consent to participate in a parent genomics study and undergoing MP. A subset of patients (n=20) participated in qualitative interviews. Results: Almost all (96%) participants were interested in receiving results which would direct cancer treatment (i.e. were actionable). A smaller majority wanted to access results which were not actionable (64%) or were variants of unknown significance (60%). Most (86%) were interested in finding out about germline findings, though not as a priority. Themes identified in interview data were: 1) Cancer is the focus; 2) Trust in clinicians; and 3) Respect for a right not to know. Conclusions: The majority of advanced cancer patients undergoing MP prioritised results which would lead to treatment options. They trusted their oncologists to help them navigate the results return process. While there was interest in knowing about other results, this was a lesser priority. Nevertheless, given high levels of interest in receiving all results, ethical aspects of not providing uninformative results requires further research, including a consideration of patient rationales for desiring this information and what health professionals can and should do to support patients in the absence of meaningful information being available. This article is protected by copyright. All rights reserved