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Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.
Introduction: Distal radial fractures (DRF) remain the most commonly encountered fracture in the Emergency Department (ED). The initial management of displaced DRFs by Emergency Physicians (EP) poses considerable resource allocation. We wished to determine the adequacy of reduction, both initially and at follow up. This data updates previously presented high level findings. Methods: We performed a mixed-methods study including patients who underwent procedural sedation and manipulation by an EP for a DRF. Radiological images performed at initial assessment, post-reduction, and clinic follow up were reviewed by a panel of orthopedic surgeons and radiologists blinded to outcomes, and assessed for evidence of displacement. Demographic data were pooled from patient records and included in statistical analysis. Results: Seventy patients were included and had follow-up completed. Initial reduction was deemed to be adequate in 37 patients (53%; 95% CI 41.32 to 64.10%). At clinic follow-up assessment, 26 reductions remained adequate; a slippage rate of 30% (95% CI of 17.37 to 45.90). Overall 7 patients (10%; 95% CI 4.65 to 19.51%) required revision of the initial reduction in the operating room. Agreement on adequacy of reduction on post-reduction radiographs between radiologists and orthopedic surgeons was 38.6% (95% CI -38.3 to -7.4, Kappa -0.229). The statistical strength of this agreement is worse than what would be expected by chance alone. There was no association found between age, sex, or of time of initial presentation and final outcomes. Conclusion: Although blinded review by specialists determined only half of initial EP DRF reductions to be radiographically adequate, only 10 percent actually required further intervention. Agreement between specialists on adequacy was poor. The majority of DRFs reduced by EPs do not require further surgical intervention.
Introduction: Determining fluid status prior to resuscitation provides a more accurate guide for appropriate fluid administration in the setting of undifferentiated hypotension. Emergency Department (ED) point of care ultrasound (PoCUS) has been proposed as a potential non-invasive, rapid, repeatable investigation to ascertain inferior vena cava (IVC) characteristics. Our goal was to determine the feasibility of using PoCUS to measure IVC size and collapsibility. Methods: This was a planned secondary analysis of data from a prospective multicentre international study investigating PoCUS in ED patients with undifferentiated hypotension. We prospectively collected data on IVC size and collapsibility using a standard data collection form in 6 centres. The primary outcome was the proportion of patients with a clinically useful (determinate) scan defined as a clearly visible intrahepatic IVC, measurable for size and collapse. Descriptive statistics are provided. Results: A total of 138 scans were attempted on 138 patients; 45.7% were women and the median age was 58 years old. Overall, one hundred twenty-nine scans (93.5%; 95% CI 87.9 to 96.7%) were determinate. 131 (94.9%; 89.7 to 97.7%) were determinate for IVC size, and 131 (94.9%; 89.7 to 97.7%) were determinate for collapsibility. Conclusion: In this analysis of 138 ED patients with undifferentiated hypotension, the vast majority of PoCUS scans to investigate IVC characteristics were determinate. Future work should include analysis of the value of IVC size and collapsibility in determining fluid status in this group.
Introduction: Patients presenting to the emergency department (ED) with hypotension have a high mortality rate and require careful yet rapid resuscitation. The use of cardiac point of care ultrasound (PoCUS) in the ED has progressed beyond the basic indications of detecting pericardial fluid and activity in cardiac arrest. We examine if finding left ventricular dysfunction (LVD) on emergency physician performed PoCUS reliably predicts the presence of cardiogenic shock in hypotensive ED patients. Methods: We prospectively collected PoCUS findings performed in 135 ED patients with undifferentiated hypotension as part of an international study. Patients with clearly identified etiologies for hypotension were excluded, along with other specific presumptive diagnoses. LVD was defined as identification of a generally hypodynamic LV in the setting of shock. PoCUS findings were collected using a standardized protocol and data collection form. All scans were performed by PoCUS-trained emergency physicians. Final shock type was defined as cardiogenic or non-cardiogenic by independent specialist blinded chart review. Results: All 135 patients had complete follow up. Median age was 56 years, 53% of patients were male. Disease prevalence for cardiogenic shock was 12% and the mortality rate was 24%. The presence of LVD on PoCUS had a sensitivity of 62.50% (95%CI 35.43% to 84.80%), specificity of 94.12% (88.26% to 97.60%), positive-LR 10.62 (4.71 to 23.95), negative-LR 0.40 (0.21 to 0.75) and accuracy of 90.37% (84.10% to 94.77%) for detecting cardiogenic shock. Conclusion: Detecting left ventricular dysfunction on PoCUS in the ED may be useful in confirming the underlying shock type as cardiogenic in otherwise undifferentiated hypotensive patients.
Introduction: Ultrasonography (US), performed in the Emergency Department (ED) by Emergency Physicians, is well established. Educational studies have shown some promise in training paramedics in US use. We have developed and piloted a novel curriculum for paramedic US education. Methods: Based on an informal needs assessment, an US curriculum for paramedics was developed to include: Basic principles, Focused assessment with sonography for trauma (FAST), cardiac, and vascular access. Participants included ED-based and pre-hospital paramedics including all paramedics with critical care training who routinely perform vascular access and procedural sedation within our ED. Comparisons were made using paired non-parametric tests (GraphPad). Results: Participants (N=9) were provided pre- reading materials prior to completing a 6-hour course, consisting of a mix of didactic and practical sessions with live models and vascular access phantoms. Each module was introduced with a 30 minute didactic session, led by an Emergency Physician trained in US, followed immediately by a 1 hour hands-on session lead by either an Emergency Physician or an Emergency Medicine Resident at a learner to instructor ratio of 3:1. At the end of the course, participants were asked to complete a short 10 minute survey that included (1) an assessment of the course quality with regard to preparatory material and course content/delivery (4 point Likert scale; excellent, good, fair, poor); (2) self reported US knowledge pre and post course on a scale of 1-10 (10 high, 1 low); (3) general yes/no questions related to the future of ECCU paramedical and (4) a subjective written section for additional comments. All participants rated the content favourably: 97% scoring it as excellent, and 3% as good. The participants median self-reported US knowledge score increased from 2/10 (IQR 2-3) to 8/10 (IQR 7.25-8; p=0.009) post- course. All comments from the text field were positive in nature. Conclusion: We report a paramedic US course curriculum, which when piloted resulted in high learner satisfaction and a high rate of self reported improvement in US knowledge. Further study will include an assessment of knowledge acquisition and practical performance. Future modifications in our curriculum will be based on needs assessment and may include additional modules.
Introduction: Situational awareness (SA) is essential for maintenance of scene safety and effective resource allocation in mass casualty incidents (MCI). Unmanned aerial vehicles (UAV) can potentially enhance SA with real-time visual feedback during chaotic and evolving or inaccessible events. The purpose of this study was to test the ability of paramedics to use UAV video from a simulated MCI to identify scene hazards, initiate patient triage, and designate key operational locations. Methods: A simulated MCI, including fifteen patients of varying acuity (blast type injuries), plus four hazards, was created on a college campus. The scene was surveyed by UAV capturing video of all patients, hazards, surrounding buildings and streets. Attendees of a provincial paramedic meeting were invited to participate. Participants received a lecture on SALT Triage and the principles of MCI scene management. Next, they watched the UAV video footage. Participants were directed to sort patients according to SALT Triage step one, identify injuries, and localize the patients within the campus. Additionally, they were asked to select a start point for SALT Triage step two, identify and locate hazards, and designate locations for an Incident Command Post, Treatment Area, Transport Area and Access/Egress routes. Summary statistics were performed and a linear regression model was used to assess relationships between demographic variables and both patient triage and localization. Results: Ninety-six individuals participated. Mean age was 35 years (SD 11), 46% (44) were female, and 49% (47) were Primary Care Paramedics. Most participants (80 (84%)) correctly sorted at least 12 of 15 patients. Increased age was associated with decreased triage accuracy [-0.04(-0.07,-0.01);p=0.031]. Fifty-two (54%) were able to localize 12 or more of the 15 patients to a 27x 20m grid area. Advanced paramedic certification, and local residency were associated with improved patient localization [2.47(0.23,4.72);p=0.031], [-3.36(-5.61,-1.1);p=0.004]. The majority of participants (78 (81%)) chose an acceptable location to start SALT triage step two and 84% (80) identified at least three of four hazards. Approximately half (53 (55%)) of participants designated four or more of five key operational areas in appropriate locations. Conclusion: This study demonstrates the potential of UAV technology to remotely provide emergency responders with SA in a MCI. Additional research is required to further investigate optimal strategies to deploy UAVs in this context.
According to diathesis–stress models, personality traits, such as negative emotionality (NE) and positive emotionality (PE), may moderate the effects of stressors on the development of depression. However, relatively little empirical research has directly examined whether NE and PE act as diatheses in the presence of stressful life events, and no research has examined whether they moderate the effect of disaster exposure on depressive symptoms. Hurricane Sandy, the second costliest hurricane in US history, offers a unique opportunity to address these gaps.
A total of 318 women completed measures of NE and PE 5 years prior to Hurricane Sandy. They were also assessed for lifetime depressive disorders on two occasions, the latter occurring an average of 1 year before the hurricane. Approximately 8 weeks after the disaster (mean = 8.40, s.d. = 1.48 weeks), participants completed a hurricane stress exposure questionnaire and a measure of current depressive symptoms.
Adjusting for lifetime history of depressive disorders, higher levels of stress from Hurricane Sandy predicted elevated levels of depressive symptoms, but only in participants with high levels of NE or low levels of PE.
These findings support the role of personality in the development of depression and suggest that personality traits can be useful in identifying those most vulnerable to major stressors, including natural disasters.
Fetal growth restriction (FGR) is defined as the failure of a fetus to attain its full genetic growth potential. It is a leading cause of stillbirth, prematurity, cerebral palsy and perinatal mortality. Small size at birth increases surviving infants’ lifelong risk of adverse health outcomes associated with the metabolic syndrome. The pathophysiology of abnormal fetal growth is extremely complex and incompletely understood, with a plethora of genetic, signalling and metabolic candidates under investigation, many of which may result in abnormal structure and function of the placenta. In contrast to, or maybe because of, the underlying complexities of FGR, the strategies clinicians have for identifying and managing this outcome are conspicuously limited. Current clinical practice is restricted to identifying pregnancies at risk of FGR, and when FGR is detected, using intensive monitoring to guide the timing of delivery to optimise fetal outcomes. Abnormal Doppler indices in the umbilical artery are strongly associated with poor perinatal outcomes and are currently the “gold standard” for clinical surveillance of the growth-restricted fetus.
Nyanza Province, Kenya is characterized by poor water quality and high diarrhoea prevalence. To address these problems, nurses in a maternal and child health clinic in Homa Bay, Kenya were trained in household water chlorination with a locally available, social marketed product, and in six steps of proper hand washing. They were asked to communicate this information to their clients. Interviews immediately following the training by nurses were conducted on 220 clients, of whom 168 (76%) reported being taught both procedures during their clinic visit. After 2 weeks, free chlorine residuals were present in stored drinking water in 67 out of 98 (68%) clients' homes and, 1 year later, in 36 out of 51 (71%) clients' homes. After 2 weeks, all six hand-washing steps were correctly demonstrated by 41 (44%) out of 93 clients, and by 17 out of 51 (34%) 1 year later. This brief, practical intervention shows promise for vulnerable populations.
The regulation of placental anion transport influences fetal accretion and placental homeostasis. We investigated whether efflux of 125I- or 36Cl- from multinucleated cytotrophoblast cells derived from human term placenta is regulated by one of three stimuli: (a) the calcium ionophore A23187, (b) a 'cocktail' of agents designed to raise intracellular levels of cAMP, (c) a hyposmotic solution. After loading with the appropriate isotope for 2 h and thorough washing, cells were exposed to sequential aliquots of buffer applied and removed each minute. Following an equilibration period of 5 min one of the stimuli was applied at room temperature At the end of the experiment the cells were lysed to give a lysate count which was used to express the count obtained from each aliquot as percentage efflux of that possible for that minute. The cAMP 'cocktail' and A23187 were applied for 5 min; the hyposmotic solution was applied for 10 min. The results for 125I- at 7 min showed that the mean efflux in the presence of hyposmotic shock was greater than control (5Σ7 ± 1Σ0 % min-1versus 2Σ2 ± 0Σ1 % min-1, respectively; mean ± S.E.M., n = 4 placentas). Similarly mean efflux at 6 min in the presence of A23187 was also significantly greater than control (6Σ5 ± 1Σ9 % min-1versus 2Σ6 ± 1Σ0 % min-1, respectively, n = 3 placentas). The mean efflux in the presence of the cAMP cocktail was not different from control at any time point. The results were qualitatively the same if 36Cl- was used in the place of 125I- and when the experiment was performed with 36Cl- in a HCO3- buffer gassed with CO2. Mean 125I- efflux at 6 min in response to hyposmotic challenge was 33 % less (P < 0Σ01) in the presence of 1 mM 4,4′-diisothiocyanatostilbene-2,2′-disulphonic acid (DIDS) and 37 % less (P < 0Σ005) in the presence of 10 µM tamoxifen but no different if the hyposmotic solution was nominally calcium free. We conclude that there are differential effects of second messengers on anion efflux from the differentiated cytotrophoblast cells.
Feto-maternal vascular (PDF-M) and amniotic-maternal (PDA-M) potential differences were measured simultaneously on seven occasions in six conscious pigs of 100-106 days gestation. Resting values of PDF-M and PDA-M were not significantly different although the range was wide. Fetal intravascular injection of 20 µg adrenaline, but not of saline, was associated with a prompt reversible change, of equal magnitude, in both PDF-M and PDA-M. In some experiments polarity was reversed. Feto-amniotic potential difference did not change. There was no change in fetal plasma K+ and Na+ concentrations. Because of the simultaneous and equal alterations in PDF-M and PDA-M following adrenaline and the anatomical configuration of the pig conceptus, we conclude that the catecholamine modifiable component of PDF-M is generated by electrogenesis in the pig placenta, probably by its chorionic (trophoblastic) cell layer.
A disturbed calcium homeostasis characterizes diabetic pregnancy. This study documents changes in bone mineral composition in diabetic pregnant rats and examines the effect of insulin replacement. Control pregnant (CP), diabetic pregnant (DP) and insulin-treated DP (DPi) rats were assessed for femoral calcium and magnesium content, bone mineral density (BMD) and the ratio of hypertrophic to maturing and proliferative cells in the femoral growth plate. DP rats showed a significantly (P < 0·01) lower body weight, femoral weight and length than CP rats. Femoral calcium and magnesium content was also significantly (P < 0·05) lower in DP rats, as was ash weight. When calcium and magnesium were normalized for ash weight no signficant differences were apparent. A significantly (P < 0·05) lower total BMD at the distal femur was seen in DP rats. This comprised a significantly (P < 0·01) lower trabecular BMD with no significant change in cortical BMD. A significantly (P < 0·05) higher ratio of hypertrophic to maturing and proliferative cells of the femoral growth plate was evident in DP animals. DPi rats showed normal blood glucose concentrations and femoral growth plate histology. DPi rats also showed normal femoral weight and length but only partially restored femoral ash weight and mineral content. Insulin failed to normalize total or trabecular BMD. Diabetes mellitus clearly has a marked effect on bone growth and mineral content in pregnancy which may be relevant to overall calcium homeostasis. The lower bone growth, bone calcium content and trabecular BMD may be unfortunate consequences of the marked hypercalciuria reported elsewhere in diabetes and may serve to maintain normocalcaemia in the disease.
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