Understanding Dwarf Galaxies in order to Understand Dark Matter

Much progress has been made in recent years by the galaxy simulation community in making realistic galaxies, mostly by more accurately capturing the effects of baryons on the structural evolution of dark matter halos at high resolutions. This progress has altered theoretical expectations for galaxy evolution within a Cold Dark Matter (CDM) model, reconciling many earlier discrepancies between theory and observations. Despite this reconciliation, CDM may not be an accurate model for our Universe. Much more work must be done to understand the predictions for galaxy formation within alternative dark matter models.Comment: Refereed contribution to the Proceedings of the Simons Symposium on Illuminating Dark Matter, to be published by Springe

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

The Changing Landscape for Stroke\ua0Prevention in AF: Findings From the GLORIA-AF Registry Phase 2

Background GLORIA-AF (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation) is a prospective, global registry program describing antithrombotic treatment patterns in patients with newly diagnosed nonvalvular atrial fibrillation at risk of stroke. Phase 2 began when dabigatran, the first non\u2013vitamin K antagonist oral anticoagulant (NOAC), became available. Objectives This study sought to describe phase 2 baseline data and compare these with the pre-NOAC era collected during phase 1. Methods During phase 2, 15,641 consenting patients were enrolled (November 2011 to December 2014); 15,092 were eligible. This pre-specified cross-sectional analysis describes eligible patients\u2019 baseline characteristics. Atrial fibrillation disease characteristics, medical outcomes, and concomitant diseases and medications were collected. Data were analyzed using descriptive statistics. Results Of the total patients, 45.5% were female; median age was 71 (interquartile range: 64, 78) years. Patients were from Europe (47.1%), North America (22.5%), Asia (20.3%), Latin America (6.0%), and the Middle East/Africa (4.0%). Most had high stroke risk (CHA2DS2-VASc [Congestive heart failure, Hypertension, Age  6575 years, Diabetes mellitus, previous Stroke, Vascular disease, Age 65 to 74 years, Sex category] score  652; 86.1%); 13.9% had moderate risk (CHA2DS2-VASc = 1). Overall, 79.9% received oral anticoagulants, of whom 47.6% received NOAC and 32.3% vitamin K antagonists (VKA); 12.1% received antiplatelet agents; 7.8% received no antithrombotic treatment. For comparison, the proportion of phase 1 patients (of N = 1,063 all eligible) prescribed VKA was 32.8%, acetylsalicylic acid 41.7%, and no therapy 20.2%. In Europe in phase 2, treatment with NOAC was more common than VKA (52.3% and 37.8%, respectively); 6.0% of patients received antiplatelet treatment; and 3.8% received no antithrombotic treatment. In North America, 52.1%, 26.2%, and 14.0% of patients received NOAC, VKA, and antiplatelet drugs, respectively; 7.5% received no antithrombotic treatment. NOAC use was less common in Asia (27.7%), where 27.5% of patients received VKA, 25.0% antiplatelet drugs, and 19.8% no antithrombotic treatment. Conclusions The baseline data from GLORIA-AF phase 2 demonstrate that in newly diagnosed nonvalvular atrial fibrillation patients, NOAC have been highly adopted into practice, becoming more frequently prescribed than VKA in Europe and North America. Worldwide, however, a large proportion of patients remain undertreated, particularly in Asia and North America. (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients With Atrial Fibrillation [GLORIA-AF]; NCT01468701

Prise en charge anesthésique de patientes obèses de classe 3 bénéficiant d’un accouchement par césarienne programmée: une étude de cohorte historique monocentrique

Purpose: The preferred neuraxial anesthetic technique for patients with class 3 obesity undergoing elective Cesarean delivery is still under debate. We aimed to describe the anesthetic technique used in our tertiary institution across body mass index (BMI) groups and different surgical incisions. Method: In this historical cohort study, we reviewed medical records of patients with a BMI ≥ 40 kg·m–2 undergoing elective Cesarean delivery between July 2014 and December 2020. We collected data on patient characteristics, anesthetic and surgical technique, and procedural times. For data analysis, we stratified patients by BMI into three different groups: 40.0–49.9 kg·m–2, 50.0–59.9 kg·m–2, and ≥ 60.0 kg·m–2. Results: We included 396 deliveries, distributed as follows: 258 with a BMI 40.0–49.9 kg·m–2, 112 with a BMI 50.0–59.9 kg·m–2, and 26 with a BMI ≥ 60.0 kg·m–2. For patients with a BMI 40.0–49.9 kg·m–2, the anesthetic technique of first choice was predominantly spinal anesthesia (71%), whereas for those with a BMI ≥ 60.0 kg·m–2, spinal anesthesia was never used as the anesthetic of first choice. With regard to the surgical incision, spinal anesthesia was almost exclusively used for patients undergoing Pfannenstiel incision and was rarely used for a higher supra- or infraumbilical transverse or midline incision. The overall incidence of general anesthesia was low (7/396, 1.8%). Anesthetic time, surgical time, and operating room time increased almost twofold in patients with a BMI ≥ 60.0 kg·m–2 compared with those with a BMI of 40.0–49.9 kg·m–2. Conclusion: Neuraxial anesthesia was successfully used in approximately 98% of patients with class 3 obesity undergoing elective Cesarean delivery. The choice of regional anesthesia technique varied with increasing BMI and with the planned surgical incision. Procedural times increased with increasing BMI. This information should prove useful for comparing anesthetic choices and outcomes in this challenging population

Color flow Doppler in spinal ultrasound: A novel technique for assessment of catheter position in labor epidurals

Background: Ultrasound is commonly used to facilitate epidural catheter placement. However, data are lacking regarding its potential to confirm its position in the epidural space. Our aim was to visualize flow in the epidural space of patients receiving epidural analgesia for labor using color flow Doppler ultrasound. Methods: We conducted a prospective observational cohort study that included patients who had delivered vaginally under epidural analgesia. We used a 5-2 mHz curvilinear probe in a left and right paramedian longitudinal oblique view to visualize the anterior and posterior complex at the interspace of epidural catheter insertion, one and two interspaces above and below. At each window, the color flow Doppler function was used to visualize flow within the epidural space on injection of normal saline (1 mL). If no flow was visualized at any interspace, one assessment at the level of insertion was repeated with a 1 mL air/saline mixture. We studied a convenience sample size of 40 patients. Results: We visualized flow in the epidural space in all 40 patients. Flow was visualized on injection of 1 mL of saline in 37/40 patients (93%). In the remaining 3/40 patients (7%), flow was visualized with an air/saline mixture. Flow on injection of saline was visualized only at the interspace of insertion in 26/37 patients (70%), at the interspace of insertion and one interspace above in 10/37 (27%), or only at one interspace above in 1/37 (3%). Flow was visualized only on the left or on the right paramedian view in 19/37 patients (51%), despite a symmetrical sensory block in all patients. Conclusion: Color flow Doppler ultrasound is a feasible and fast way to determine flow in the epidural space in the obstetric population. Its potential clinical uses are confirmation of the epidural catheter position after placement, as well as troubleshooting of unsatisfactory epidural analgesia. Interestingly, our results suggest that epidural catheters predominantly remain at the interspace of insertion. Trial registration number: NCT05126745

Predictors and Hospital Outcomes in Pregnant Patients Undergoing Extracorporeal Membrane Oxygenation: A Nationwide Study

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is increasingly used in patients with severe cardiorespiratory collapse. Although prior large database reviews of ECMO use in the peripartum population exist, they do not stratify by ECMO indication nor do they include obstetric conditions such as preeclampsia. Our objective was to characterize the incidence, indication-associated mortality, and factors associated with mortality in pregnant patients who underwent ECMO. METHODS: We examined the United States National Inpatient Sample database to identify hospitalizations for pregnancy from January 1, 2010 to December 31, 2016. We identified pregnant patients who underwent ECMO using International Classification of Diseases ninth and tenth revisions codes. The primary outcome was in-hospital all-cause mortality across pregnant patients who underwent ECMO for any indication. We evaluated the indication for ECMO, incidence, prevalence of risk factors, comorbidities and conditions, and their association with in-hospital mortality. RESULTS: Fifty-nine of 5'346,517 pregnant patients underwent ECMO during our study period (incidence, 1.1; 95% confidence interval [CI], 0.84-1.4 per 100,000 hospitalizations). Indications for ECMO support included respiratory failure (79.7%), cardiogenic shock (64.4%), or circulatory arrest (25.4%). Most patients (57.6%) had more than 1 indication. The overall in-hospital mortality rate was 30.5%. Mortality was 29.8% in patients with respiratory failure, 39.5% with cardiogenic shock, 46.7% with cardiac arrest, and 42.4% in those with combined diagnoses. Cardiogenic shock was associated with a significantly higher mortality rate and adjusted odds ratio 5.0 (95% CI, 1.25-27.0). Most patients (62.7%) had one or more comorbidities. CONCLUSIONS: The frequency of ECMO use across the pregnant population was low over this time period, with a mortality rate of 1 in 3 patients. Mortality was greatest in patients with cardiogenic shock. Further work is needed to understand how best to improve ECMO outcomes in pregnant patients

Breathing variability—implications for anaesthesiology and intensive care

The respiratory system reacts instantaneously to intrinsic and extrinsic inputs. This adaptability results in significant fluctuations in breathing parameters, such as respiratory rate, tidal volume, and inspiratory flow profiles. Breathing variability is influenced by several conditions, including sleep, various pulmonary diseases, hypoxia, and anxiety disorders. Recent studies have suggested that weaning failure during mechanical ventilation may be predicted by low respiratory variability. This review describes methods for quantifying breathing variability, summarises the conditions and comorbidities that affect breathing variability, and discusses the potential implications of breathing variability for anaesthesia and intensive care

Quality and Quantity of Sleep and Factors Associated With Sleep Disturbance in Hospitalized Patients

Importance: Although inadequate sleep has a proven negative association with health care outcomes, to date, no large-scale studies have examined sleep in general hospital wards. Objectives: To assess the subjective quantity and quality of sleep and to identify the hospital-related factors associated with sleep disturbances in hospitalized patients. Design: For this nationwide, single-day, multicenter, cross-sectional, observational study, which took place on February 22, 2017, all hospitals in the Netherlands were encouraged by word of mouth and conventional and social media to participate in this study. A total of 39 hospitals participated. Included patients were at least 18 years of age, were able to give informed consent, and had spent at least 1 night in a regular-care hospital ward. Exposures: Hospitalization in a regular-care ward. Main Outcomes and Measures: Quantity and quality of last night's sleep in the hospital compared with habitual sleep at home the month before hospitalization. The Consensus Sleep Diary and the Dutch-Flemish Patient-Reported Outcomes Measurement Information System (PROMIS) Sleep Disturbance item bank were used. Complementary questions assessed sleep-disturbing factors. Results: A total of 2005 patients were included (median age, 68 years; interquartile range, 57-77 years; 994 of 1935 [51.4%] were male [70 patients did not identify their sex]). Compared with habitual sleep at home, the total sleep time in the hospital was 83 minutes (95% CI, 75-92 minutes; P < .001) shorter. The mean number of nocturnal awakenings was 2.0 (95% CI, 1.9-2.1) times at home vs 3.3 (95% CI, 3.2-3.5) times during hospitalization (P < .001). Patients woke up 44 minutes (95% CI, 44-45 minutes; P < .001) earlier than their habitual wake-up time at home. A total of 1344 patients (70.4%) reported having been awakened by external causes, which in 718 (35.8%) concerned hospital staff. All aspects of sleep quality measured using PROMIS questions were rated worse during hospitalization than at home. The most reported sleep-disturbing factors were noise of other patients, medical devices, pain, and toilet visits. Conclusions and Relevance: This study demonstrated that the duration and quality of sleep in hospitalized patients were significantly affected and revealed many potentially modifiable hospital-related factors negatively associated with sleep. Raising awareness about the importance of adequate sleep in the vulnerable hospital population and introducing interventions to target sleep-disturbing factors may improve healing