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We review successes and challenges from five recent subglacial bedrock drilling campaigns intended to find evidence for Antarctic Ice Sheet retreat during warm periods in the geologic past. Insights into times when the polar ice sheets were smaller than present serve as guiding information for modeling efforts that aim to predict the rate and magnitude of future sea level rise that would accompany major retreat of the Antarctic Ice Sheet. One method to provide direct evidence for the timing of deglaciations and minimum extent of prior ice sheets is to extract subglacial bedrock cores for cosmogenic nuclide analysis from beneath the modern ice sheet surface. Here we summarize the lessons learned from five field seasons tasked with obtaining bedrock cores from shallow depths (<120 m beneath ice surface) across West Antarctica since 2016. We focus our findings on drilling efforts and technology and geophysical surveys with ground-penetrating radar. Shallow subglacial drilling provides a high risk, high reward means to test for past instabilities of the Antarctic Ice Sheet, and we highlight key challenges and solutions to increase the likelihood of success for future subglacial drilling efforts in polar regions.
Little is known about when youth may be at greatest risk for attempting suicide, which is critically important information for the parents, caregivers, and professionals who care for youth at risk. This study used adolescent and parent reports, and a case-crossover, within-subject design to identify 24-hour warning signs (WS) for suicide attempts.
Methods
Adolescents (N = 1094, ages 13 to 18) with one or more suicide risk factors were enrolled and invited to complete bi-weekly, 8–10 item text message surveys for 18 months. Adolescents who reported a suicide attempt (survey item) were invited to participate in an interview regarding their thoughts, feelings/emotions, and behaviors/events during the 24-hours prior to their attempt (case period) and a prior 24-hour period (control period). Their parents participated in an interview regarding the adolescents’ behaviors/events during these same periods. Adolescent or adolescent and parent interviews were completed for 105 adolescents (81.9% female; 66.7% White, 19.0% Black, 14.3% other).
Results
Both parent and adolescent reports of suicidal communications and withdrawal from social and other activities differentiated case and control periods. Adolescent reports also identified feelings (self-hate, emotional pain, rush of feelings, lower levels of rage toward others), cognitions (suicidal rumination, perceived burdensomeness, anger/hostility), and serious conflict with parents as WS in multi-variable models.
Conclusions
This study identified 24-hour WS in the domains of cognitions, feelings, and behaviors/events, providing an evidence base for the dissemination of information about signs of proximal risk for adolescent suicide attempts.
The trauma care system in Ireland is being re-configured to have major trauma centers for severe injuries and other sites for less severe injuries. This is to ensure patients are brought quickly to the most appropriate hospital to manage their injuries. The National Ambulance Service (NAS) electronic Patient Care Record (ePCR) records what happens to patients before they reach the hospital and the Major Trauma Audit (MTA) captures data on patients’ hospital treatment. These datasets are currently separate and if they could be joined, they would inform important decisions on which hospitals to take patients. This study aims to investigate joining these datasets to create a seamless database of the patient journey from roadside to recovery.
Method:
Proof of Concept–The ePCR and MTA datasets will be linked on a once-off basis. The combined anonymized dataset will then be analyzed to identify pre-hospital characteristics that determine the need to bypass smaller hospitals and bring patients to a larger major trauma center or trauma unit.
Stakeholder input for ongoing dataset combination and utilization–A stakeholder consultation process will explore the best way to make a GDPR-compliant combination of datasets on an on-going basis, including geo-location data and the inclusion of patient reported outcome measures. This will incorporate the requirements of the Data Protection Commissioner, National Office of Clinical Audit, patients, clinicians, NAS, HSE and other stakeholders.
Geospatial implications of major trauma services–Once ongoing data combination is approved, we will determine geospatial implications of the trauma network for prehospital care configuration and the patient journey.
Results:
Study results will inform prehospital service configuration to ensure safe and equitable patient management.
Conclusion:
The data arising from this study will capture the full trauma patient journey. This data is essential to inform policy and practice for trauma care in Ireland.
Refractory depression is a devastating condition with significant morbidity, mortality, and societal cost. Approximately 15% of patients with major depressive disorder are refractory to currently available treatments. We hypothesized metabolic abnormalities contributing to treatment refractory depression are associated with distinct findings identifiable in the cerebrospinal fluid (CSF). Our hypothesis was confirmed by a previous small case-controlled study. Here we present a second, larger replication study.
Methods
We conducted a case-controlled, targeted, metabolomic evaluation of 141 adolescent and adult patients with well-characterized history of depression refractory to three maximum-dose, adequate-duration medication treatments, and 36 healthy controls. Plasma, urine, and CSF metabolic profiling were performed by coupled gas chromatography/mass spectrometry, and high-performance liquid chromatography, electrospray ionization, tandem mass spectrometry.
Results
Abnormalities were identified in 67 of 141 treatment refractory depression participants. The CSF abnormalities included: low cerebral folate (n = 20), low tetrahydrobiopterin intermediates (n = 11), and borderline low-tetrahydrobiopterin intermediates (n = 20). Serum abnormalities included abnormal acylcarnitine profile (n = 12) and abnormal serum amino acids (n = 20). Eighteen patients presented with two or more abnormal metabolic findings. Sixteen patients with cerebral folate deficiency and seven with low tetrahydrobiopterin intermediates in CSF showed improvement in depression symptom inventories after treatment with folinic acid and sapropterin, respectively. No healthy controls had a metabolite abnormality.
Conclusions
Examination of metabolic disorders in treatment refractory depression identified an unexpectedly large proportion of patients with potentially treatable abnormalities. The etiology of these abnormalities and their potential roles in pathogenesis remain to be determined.
A growing volume of research suggests that religion protects against late-life suicide, but it remains unclear whether effects are relevant to clinical samples, which facets of religion are most relevant, and variations over the course of mood disorders (e.g. during periods of euthymia, depression, and/or heightened suicidality).
Method
Eighty adults aged 55–85 years with mood disorders completed assessments of religion (affiliation, service attendance, importance of religion, belief and faith in God), depression, and suicidality over time (M = 7.31 measurements over M = 727 days). We computed metrics to identify mean and maximum levels of depression and suicidality, and the number of episodes of significant depression and suicidality experienced by each participant.
Results
Religious affiliation and importance of religion, but not service attendance, belief, or faith in God, were associated with lower mean and maximum depression. Conversely, all facets of religion predicted significantly lower mean and maximum levels of suicidality (rs ranging from −0.24 to −0.39), and substantially less likelihood of experiencing significant suicidality during the study (ORs ranging from 0.19 to 0.33). Service attendance, belief, and faith in God predicted less suicidality even among individuals who did not affiliate with a religious group.
Conclusions
Religious factors, particularly faith in God, are associated with substantially less suicidality over time among older adults with mood disorders, irrespective of religious affiliation.
Agitation is a common complication of Alzheimer’s dementia (Agit-AD) associated with substantial morbidity, high healthcare service utilization, and adverse emotional and physical impact on care partners. There are currently no FDA-approved pharmacological treatments for Agit-AD. We present the study design and baseline data for an ongoing multisite, three-week, double-blind, placebo-controlled, randomized clinical trial of dronabinol (synthetic tetrahydrocannabinol [THC]), titrated to a dose of 10 mg daily, in 80 participants to examine the safety and efficacy of dronabinol as an adjunctive treatment for Agit-AD. Preliminary findings for 44 participants enrolled thus far show a predominately female, white sample with advanced cognitive impairment (Mini Mental Status Examination mean 7.8) and agitation (Neuropsychiatric Inventory-Clinician Agitation subscale mean 14.1). Adjustments to study design in light of the COVID-19 pandemic are described. Findings from this study will provide guidance for the clinical utility of dronabinol for Agit-AD. ClinicalTrials.gov Identifier: NCT02792257.
Stretcher transport isolators provide mobile, high-level biocontainment outside the hospital for patients with highly infectious diseases, such as Ebola virus disease. Air quality within this confined space may pose human health risks.
Methods:
Ambient air temperature, relative humidity, and CO2 concentration were monitored within an isolator during 2 operational exercises with healthy volunteers, including a ground transport exercise of approximately 257 miles. In addition, failure of the blower unit providing ambient air to the isolator was simulated. A simple compartmental model was developed to predict CO2 and H2O concentrations within the isolator.
Results:
In both exercises, CO2 and H2O concentrations were elevated inside the isolator, reaching steady-state values of 4434 ± 1013 ppm CO2 and 22 ± 2 mbar H2O in the first exercise and 3038 ± 269 ppm CO2 and 20 ± 1 mbar H2O in the second exercise. When blower failure was simulated, CO2 concentration exceeded 10 000 ppm within 8 minutes. A simple compartmental model predicted CO2 and H2O concentrations by accounting for human emissions and blower air exchange.
Conclusions:
Attention to air quality within stretcher transport isolators (including adequate ventilation to prevent accumulation of CO2 and other bioeffluents) is needed to optimize patient safety.
The Subglacial Antarctic Lakes Scientific Access (SALSA) Project accessed Mercer Subglacial Lake using environmentally clean hot-water drilling to examine interactions among ice, water, sediment, rock, microbes and carbon reservoirs within the lake water column and underlying sediments. A ~0.4 m diameter borehole was melted through 1087 m of ice and maintained over ~10 days, allowing observation of ice properties and collection of water and sediment with various tools. Over this period, SALSA collected: 60 L of lake water and 10 L of deep borehole water; microbes >0.2 μm in diameter from in situ filtration of ~100 L of lake water; 10 multicores 0.32–0.49 m long; 1.0 and 1.76 m long gravity cores; three conductivity–temperature–depth profiles of borehole and lake water; five discrete depth current meter measurements in the lake and images of ice, the lake water–ice interface and lake sediments. Temperature and conductivity data showed the hydrodynamic character of water mixing between the borehole and lake after entry. Models simulating melting of the ~6 m thick basal accreted ice layer imply that debris fall-out through the ~15 m water column to the lake sediments from borehole melting had little effect on the stratigraphy of surficial sediment cores.
Previous studies indicate that “hesitation” and “skepticism” are important barriers to the development of renewable energy industries in the United States. We examine whether key pecuniary and nonpecuniary characteristics of bioenergy crops underlie the hesitation argument. Based on a stated choice experiment, we find that Midwestern producers appreciate certain crop attributes that are found in switchgrass, but not in conventional crops. We also find that producers would be willing to grow switchgrass-like crops for net margins between $222/acre/year and $247/acre/year in marginal counties. We argue that farmers’ hesitation and skepticism toward bioenergy crops can be overcome.
Recent archaeological efforts to explain the emergence and persistence of social inequality have been hampered by little information about how wealth was transmitted across generations, and how it may have accumulated or diminished over time. Building on studies that have shown domestic architecture to be an excellent material expression of household wealth, we provide a method for reconstructing the amount of labor invested in house construction among the Hohokam of southern Arizona. We also account for different architectural styles from different time periods. To illustrate the utility of the method for addressing broader social issues, we investigate the relationship among population increases, resource shortages, and wealth differentials at Pueblo Grande—one of the preeminent settlements in the Hohokam region. Inequality at Pueblo Grande was tracked over time and compared to similar results at the Grewe site. High-status households at both sites were distinguished architecturally by larger and, in some instances, more elaborate houses. The proximity of these households to public areas for ceremonial expression further suggests that access to ritual played a key role in creating and maintaining inequality in Hohokam society.
Clinical assessments are a primary method for ascertaining suicide risk, yet the language used across measures is inconsistent. The implications of these discrepancies for adolescent responding are unknown, which is troubling as multiple research areas (i.e. on culture, mental health language, and suicide communication) indicate individuals from varying sociodemographic backgrounds may communicate differently regarding mental health concerns. The aims of the current study are to investigate whether a geographically diverse sample of adolescents respond differently to directly and indirectly phrased suicide attempt questions (i.e. directly phrased includes the term ‘suicide’ and indirectly asks about suicidal behavior without using ‘suicide’), and to examine whether sociodemographic factors and history of mental health service usage relate to endorsement differences.
Methods
Participants were N = 5909 adolescents drawn from the Emergency Department Screening for Teens at Risk for Suicide multi-site study. The lifetime suicide attempt was assessed with two items from an adapted version of the Columbia Suicide Severity Rating Scale (C-SSRS; Posner et al., 2008): (1) a directly phrased question asking about ‘suicide attempts’ and (2) an indirectly phrased question providing the definition of an attempt.
Results
An adolescent majority (83.7%) consistently reported no lifetime suicide attempt across items, 10.1% consistently reported one or more lifetime attempts across items, and 6.2% of adolescents responded discordantly to the items.
Conclusions
Multivariable models indicated multiple demographic and mental health service variables significantly predicted discordant responding, with a notable finding being that father/stepfather education level at or below high school education predicted endorsing only the direct question.
We consider the sum
$\sum 1/\gamma $
, where
$\gamma $
ranges over the ordinates of nontrivial zeros of the Riemann zeta-function in an interval
$(0,T]$
, and examine its behaviour as
$T \to \infty $
. We show that, after subtracting a smooth approximation
$({1}/{4\pi }) \log ^2(T/2\pi ),$
the sum tends to a limit
$H \approx -0.0171594$
, which can be expressed as an integral. We calculate H to high accuracy, using a method which has error
$O((\log T)/T^2)$
. Our results improve on earlier results by Hassani [‘Explicit approximation of the sums over the imaginary part of the non-trivial zeros of the Riemann zeta function’, Appl. Math. E-Notes16 (2016), 109–116] and other authors.
Suicide and cardiovascular disease rank among the leading causes of disability and premature mortality worldwide. Young adult suicide attempters are at increased risk of mortality from cardiovascular disease even compared to those with major depressive disorder suggesting an increased burden of cardiovascular risk factors. We compared the cardiovascular risk burden between youth attempters and other high-risk individuals.
Methods
Participants were from the Collaborative Psychiatric Epidemiology Surveys (CPES), a U.S. population-based study, aged 18–30 years [suicide attempt (SA): n = 303; suicidal ideation (SI): n = 451; controls: n = 3671]; and psychiatric inpatients admitted for a SA (n = 38) or SI (n = 40) and healthy controls (n = 37) aged 15–30 years. We computed a cardiovascular risk score and high- and low-risk latent classes based on risk factors of high blood pressure, obesity, and smoking.
Results
Suicide attempters showed an increased cardiovascular risk score (CPES: B = 0.43, 95% confidence interval (CI) 0.31–0.54, p < 0.001; inpatient sample: B = 1.61, 95% CI 0.53–2.68, p = 0.004) compared to controls. They were also more likely to be classified in the high cardiovascular risk group (CPES: odds ratio (OR) 3.36, 95% CI 1.67–6.78, p = 0.001; inpatient sample: OR 9.89, 95% CI 1.38–85.39, p = 0.03) compared to those with SI (CPES: OR 1.15, 95% CI 0.55–2.39, p = 0.71; inpatient sample: OR 1.91, 95% CI 0.25–15.00, p = 0.53).
Conclusions
Youth attempters show an increased burden for cardiovascular risk compared to other high-risk individuals in inpatient and population-based samples. Clinicians should pay particular attention to cardiovascular risk factors among suicide attempters in order to reduce their risk for cardiovascular events.
Reward Deficiency Syndrome (RDS) is an umbrella term for all drug and nondrug addictive behaviors, due to a dopamine deficiency, “hypodopaminergia.” There is an opioid-overdose epidemic in the USA, which may result in or worsen RDS. A paradigm shift is needed to combat a system that is not working. This shift involves the recognition of dopamine homeostasis as the ultimate treatment of RDS via precision, genetically guided KB220 variants, called Precision Behavioral Management (PBM). Recognition of RDS as an endophenotype and an umbrella term in the future DSM 6, following the Research Domain Criteria (RDoC), would assist in shifting this paradigm.
To assess the influence of mild behavioral impairment (MBI) on the cognitive performance of older adults who are cognitively healthy or have mild cognitive impairment (MCI).
Methods:
Secondary data analysis of a sample (n = 497) of older adults from the Florida Alzheimer’s Disease Research Center who were either cognitively healthy (n = 285) or diagnosed with MCI (n = 212). Over half of the sample (n = 255) met the operationalized diagnostic criteria for MBI. Cognitive domains of executive function, attention, short-term memory, and episodic memory were assessed using a battery of neuropsychological tests.
Results:
Older adults with MBI performed worse on tasks of executive function, attention, and episodic memory compared to those without MBI. A significant interaction revealed that persons with MBI and MCI performed worse on tasks of episodic memory compared to individuals with only MCI, but no significant differences were found in performance in cognitively healthy older adults with or without MBI on this cognitive domain. As expected, cognitively healthy older adults performed better than individuals with MCI on every domain of cognition.
Conclusions:
The present study found evidence that independent of cognitive status, individuals with MBI performed worse on tests of executive function, attention, and episodic memory than individuals without MBI. Additionally, those with MCI and MBI perform significantly worse on episodic memory tasks than individuals with only MCI. These results provide support for a unique cognitive phenotype associated with MBI and highlight the necessity for assessing both cognitive and behavioral symptoms.
We examine the performance of the Diagnostic and Statistical Manual of Mental Disorders-fifth edition (DSM-5) persistent complex bereavement-related disorder (PCBD) criteria in bereaved adults to identify prolonged grief cases determined prospectively.
Methods
Bereaved adults (n = 138) were assessed at 8, 21, 32, 67, and 90 months after the sudden death of a spouse or close relative. We used latent class growth analysis to identify the longitudinal trajectories of grief assessed using the Inventory for Complicated Grief. To validate the trajectory that corresponded to prolonged grief, we examined the baseline predictors of these trajectories and their relationship with functional impairment.
Results
We found three distinct trajectories of grief reactions. One of these trajectories (13.8%) showed high and sustained grief reactions that persisted for almost 7.5 years after the death. Participants with prolonged grief showed greater functional impairment [relative risk ratio (RRR) = 0.82, 95% confidence interval (CI): 0.70 to −0.97; p = 0.02] and higher self-reported depression (RRR = 1.21, 95% CI 1.09 to 1.96; p = 0.001) than participants whose grief reactions subsided over time. The original PCBD (requiring 6 criterion C symptoms) criteria correctly identified cases (57.9–94.7%) with perfect specificity (100%) but low to high sensitivity (5.6–81.3%); however, its sensitivity increased when revising criterion C to require ⩾3 (45.5–94.1%). The dimensional approach showed high sensitivity (0.50–1) and specificity (0.787–0.97).
Conclusions
We recommend revisions to the PCBD criteria, which are overly restrictive and may exclude cases with clinically significant grief-related distress and impairment. In the meantime, clinicians need to monitor grief symptoms over time using available dimensional approaches to reduce the burden of grief.
Formularies are used by payers to optimize access and ensure the appropriate use of medications. Lack of follow-up and re-evaluation can lead to outdated formularies that are not reflective of current evidence. Formulary modernization, an approach to re-align formularies with current evidence has proven successful. The Ontario Drug Policy Research Network (ODPRN) launched a framework for conducting comprehensive drug-class reviews. This commentary describes the individual components of this framework and lessons learned through completion of 12 reviews between 2013 and 2016. We present the ODPRN drug-class review of treatments for chronic hepatitis B as a case example to illustrate the components and impact. The incorporation of foundational health technology assessment components such as economic evaluations and knowledge synthesis with contextualizing evidence such as patient and clinician perspectives (through qualitative studies), real-world evidence (through data analytics), and cross-jurisdictional comparisons (through environmental scans and data analytics), successfully developed jurisdictionally specific policy recommendations grounded in up-to-date evidence. The ODPRN framework for conducting comprehensive drug-class reviews is a robust and feasible approach to conduct formulary modernization. This framework allows for actionable and specific policies which are likely to be considered by decision makers. Adoption of similar frameworks in other jurisdictions may improve uptake of evidence-informed policy recommendations.
Simulation plays an integral role in the Canadian healthcare system with applications in quality improvement, systems development, and medical education. High-quality, simulation-based research will ensure its effective use. This study sought to summarize simulation-based research activity and its facilitators and barriers, as well as establish priorities for simulation-based research in Canadian emergency medicine (EM).
Methods
Simulation-leads from Canadian departments or divisions of EM associated with a general FRCP-EM training program surveyed and documented active EM simulation-based research at their institutions and identified the perceived facilitators and barriers. Priorities for simulation-based research were generated by simulation-leads via a second survey; these were grouped into themes and finally endorsed by consensus during an in-person meeting of simulation leads. Priority themes were also reviewed by senior simulation educators.
Results
Twenty simulation-leads representing all 14 invited institutions participated in the study between February and May, 2018. Sixty-two active, simulation-based research projects were identified (median per institution = 4.5, IQR 4), as well as six common facilitators and five barriers. Forty-nine priorities for simulation-based research were reported and summarized into eight themes: simulation in competency-based medical education, simulation for inter-professional learning, simulation for summative assessment, simulation for continuing professional development, national curricular development, best practices in simulation-based education, simulation-based education outcomes, and simulation as an investigative methodology.
Conclusion
This study summarized simulation-based research activity in EM in Canada, identified its perceived facilitators and barriers, and built national consensus on priority research themes. This represents the first step in the development of a simulation-based research agenda specific to Canadian EM.
Silphium spp. have garnered interest in Europe as a bioenergy crop and in North America as a perennial oilseed crop. However, very little has been done at this early stage of domestication to characterize wild collections for many key characteristics, including important oilseed traits. The objective of this work was to develop a basic understanding of how biogeography and associated population genetic forces have shaped seed phenotypes in plant collections across the native range of Silphium integrifolium Michx. (Asteraceae: Heliantheae), the primary domestication candidate for oilseed use. A collection of 53 accessions was grown in a common environment in Salina, KS, which is a location well within the native range of the species in central North America. Plants from each collection site were randomly mated by hand to produce seed representative of each accession, and the seeds subjected to seed dimensional trait, oil content and oil composition analyses. Kernel width varied along a latitudinal cline of collection site, while kernel length varied across a longitudinal cline. Palmitic and linoleic acids were inversely correlated with each other and varied along a longitudinal cline of the collection site. The results indicate that accessions collected from more southwesterly sites tended to have larger seed and those from more westerly sites had higher linoleic acid content and lower palmitic and myristic acids, which are all desirable phenotypes for an oilseed Silphium.
Studies of domestic architectural variation are rare in archaeological research, possibly because the essential methods remain underdeveloped. To encourage a comparative approach to explaining the construction differences in household dwellings, we designed and utilized objective and easily applied means to calculate labor costs for constructing a variety of domestic architectural styles in Hohokam society. We applied Abrams's (1989, 1994) approach, labelled “architectural energetics,” which converts architecture into its labor equivalents for building structures. By doing so, we derived standard units of measurement that promote comparative analysis. To demonstrate the method's utility, we turned to the pithouses and adobe surface structures at Pueblo Grande. We wanted to test whether the history of construction was driven by environmental degradation, and, in particular, a depletion over time of wood resources for home building (see Loendorf and Lewis 2017). Our analysis indicated that factors in addition to wood depletion likely contributed to the architectural changes at Pueblo Grande and across the Hohokam world.