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Subglacial hydrological systems require innovative technological solutions to access and observe. Wireless sensor platforms can be used to collect and return data, but their performance in deep and fast-moving ice requires quantification. We report experimental results from Cryoegg: a spherical probe that can be deployed into a borehole or moulin and transit through the subglacial hydrological system. The probe measures temperature, pressure and electrical conductivity in situ and returns all data wirelessly via a radio link. We demonstrate Cryoegg's utility in studying englacial channels and moulins, including in situ salt dilution gauging. Cryoegg uses VHF radio to transmit data to a surface receiving array. We demonstrate transmission through up to 1.3 km of cold ice – a significant improvement on the previous design. The wireless transmission uses Wireless M-Bus on 169 MHz; we present a simple radio link budget model for its performance in cold ice and experimentally confirm its validity. Cryoegg has also been tested successfully in temperate ice. The battery capacity should allow measurements to be made every 2 h for more than a year. Future iterations of the radio system will enable Cryoegg to transmit data through up to 2.5 km of ice.
It is not clear to what extent associations between schizophrenia, cannabis use and cigarette use are due to a shared genetic etiology. We, therefore, examined whether schizophrenia genetic risk associates with longitudinal patterns of cigarette and cannabis use in adolescence and mediating pathways for any association to inform potential reduction strategies.
Associations between schizophrenia polygenic scores and longitudinal latent classes of cigarette and cannabis use from ages 14 to 19 years were investigated in up to 3925 individuals in the Avon Longitudinal Study of Parents and Children. Mediation models were estimated to assess the potential mediating effects of a range of cognitive, emotional, and behavioral phenotypes.
The schizophrenia polygenic score, based on single nucleotide polymorphisms meeting a training-set p threshold of 0.05, was associated with late-onset cannabis use (OR = 1.23; 95% CI = 1.08,1.41), but not with cigarette or early-onset cannabis use classes. This association was not mediated through lower IQ, victimization, emotional difficulties, antisocial behavior, impulsivity, or poorer social relationships during childhood. Sensitivity analyses adjusting for genetic liability to cannabis or cigarette use, using polygenic scores excluding the CHRNA5-A3-B4 gene cluster, or basing scores on a 0.5 training-set p threshold, provided results consistent with our main analyses.
Our study provides evidence that genetic risk for schizophrenia is associated with patterns of cannabis use during adolescence. Investigation of pathways other than the cognitive, emotional, and behavioral phenotypes examined here is required to identify modifiable targets to reduce the public health burden of cannabis use in the population.
First episode psychosis (FEP) patients who use cannabis experience more frequent psychotic and euphoric intoxication experiences compared to controls. It is not clear whether this is consequent to patients being more vulnerable to the effects of cannabis use or to their heavier pattern of use. We aimed to determine whether extent of use predicted psychotic-like and euphoric intoxication experiences in patients and controls and whether this differs between groups.
We analysed data on patients who had ever used cannabis (n = 655) and controls who had ever used cannabis (n = 654) across 15 sites from six countries in the EU-GEI study (2010–2015). We used multiple regression to model predictors of cannabis-induced experiences and to determine if there was an interaction between caseness and extent of use.
Caseness, frequency of cannabis use and money spent on cannabis predicted psychotic-like and euphoric experiences (p ⩽ 0.001). For psychotic-like experiences (PEs) there was a significant interaction for caseness × frequency of use (p < 0.001) and caseness × money spent on cannabis (p = 0.001) such that FEP patients had increased experiences at increased levels of use compared to controls. There was no significant interaction for euphoric experiences (p > 0.5).
FEP patients are particularly sensitive to increased psychotic-like, but not euphoric experiences, at higher levels of cannabis use compared to controls. This suggests a specific psychotomimetic response in FEP patients related to heavy cannabis use. Clinicians should enquire regarding cannabis related PEs and advise that lower levels of cannabis use are associated with less frequent PEs.
The ‘jumping to conclusions’ (JTC) bias is associated with both psychosis and general cognition but their relationship is unclear. In this study, we set out to clarify the relationship between the JTC bias, IQ, psychosis and polygenic liability to schizophrenia and IQ.
A total of 817 first episode psychosis patients and 1294 population-based controls completed assessments of general intelligence (IQ), and JTC, and provided blood or saliva samples from which we extracted DNA and computed polygenic risk scores for IQ and schizophrenia.
The estimated proportion of the total effect of case/control differences on JTC mediated by IQ was 79%. Schizophrenia polygenic risk score was non-significantly associated with a higher number of beads drawn (B = 0.47, 95% CI −0.21 to 1.16, p = 0.17); whereas IQ PRS (B = 0.51, 95% CI 0.25–0.76, p < 0.001) significantly predicted the number of beads drawn, and was thus associated with reduced JTC bias. The JTC was more strongly associated with the higher level of psychotic-like experiences (PLEs) in controls, including after controlling for IQ (B = −1.7, 95% CI −2.8 to −0.5, p = 0.006), but did not relate to delusions in patients.
Our findings suggest that the JTC reasoning bias in psychosis might not be a specific cognitive deficit but rather a manifestation or consequence, of general cognitive impairment. Whereas, in the general population, the JTC bias is related to PLEs, independent of IQ. The work has the potential to inform interventions targeting cognitive biases in early psychosis.
Daily use of high-potency cannabis has been reported to carry a high risk for developing a psychotic disorder. However, the evidence is mixed on whether any pattern of cannabis use is associated with a particular symptomatology in first-episode psychosis (FEP) patients.
We analysed data from 901 FEP patients and 1235 controls recruited across six countries, as part of the European Network of National Schizophrenia Networks Studying Gene-Environment Interactions (EU-GEI) study. We used item response modelling to estimate two bifactor models, which included general and specific dimensions of psychotic symptoms in patients and psychotic experiences in controls. The associations between these dimensions and cannabis use were evaluated using linear mixed-effects models analyses.
In patients, there was a linear relationship between the positive symptom dimension and the extent of lifetime exposure to cannabis, with daily users of high-potency cannabis having the highest score (B = 0.35; 95% CI 0.14–0.56). Moreover, negative symptoms were more common among patients who never used cannabis compared with those with any pattern of use (B = −0.22; 95% CI −0.37 to −0.07). In controls, psychotic experiences were associated with current use of cannabis but not with the extent of lifetime use. Neither patients nor controls presented differences in depressive dimension related to cannabis use.
Our findings provide the first large-scale evidence that FEP patients with a history of daily use of high-potency cannabis present with more positive and less negative symptoms, compared with those who never used cannabis or used low-potency types.
A notable increase in immigration into the United States over the past half century, coupled with its recent geographic dispersion into new communities nationwide, has fueled contact among a wider set of individuals and groups than ever before. Past research has helped us understand Whites’ and Blacks’ attitudes toward immigrants and immigration, and even how contact between Blacks and Whites have shaped their attitudes toward one another. Nevertheless, how contact between Blacks and Whites may correspond with attitudes toward immigrants is not as well understood. Drawing on an original representative survey, we examine U.S.-born Whites’ and Blacks’ attitudes toward Mexican and South Asian Indian immigrants within the context of ongoing relations between the former two U.S.-born communities. Informed by research on the secondary transfer effect (STE), we model how the frequency of contact between U.S.-born Whites and Blacks predicts each group’s receptivity toward two differentially positioned immigrant groups, first-generation Mexicans and South Asian Indians. Multivariate analysis indicates that, among Whites, more frequent contact with Blacks is positively associated with greater receptivity toward both immigrant outgroups, even after controlling for Whites’ individual perceptions of threat, their direct contact with the two immigrant groups, and the perceived quality of such contact. Among Blacks, however, we find less consistent evidence that frequent contact with Whites is associated with attitudes toward either immigrant group. While varied literatures across multiple disciplines have suggested that interracial relations among the U.S.-born may be associated with receptivity toward immigrant newcomers, our results uniquely highlight the importance of considering how U.S.-born groups are positioned in relation to immigrants and to each other when examining such effects.
To identify potential participants for clinical trials, electronic health records (EHRs) are searched at potential sites. As an alternative, we investigated using medical devices used for real-time diagnostic decisions for trial enrollment.
To project cohorts for a trial in acute coronary syndromes (ACS), we used electrocardiograph-based algorithms that identify ACS or ST elevation myocardial infarction (STEMI) that prompt clinicians to offer patients trial enrollment. We searched six hospitals’ electrocardiograph systems for electrocardiograms (ECGs) meeting the planned trial’s enrollment criterion: ECGs with STEMI or > 75% probability of ACS by the acute cardiac ischemia time-insensitive predictive instrument (ACI-TIPI). We revised the ACI-TIPI regression to require only data directly from the electrocardiograph, the e-ACI-TIPI using the same data used for the original ACI-TIPI (development set n = 3,453; test set n = 2,315). We also tested both on data from emergency department electrocardiographs from across the US (n = 8,556). We then used ACI-TIPI and e-ACI-TIPI to identify potential cohorts for the ACS trial and compared performance to cohorts from EHR data at the hospitals.
Receiver-operating characteristic (ROC) curve areas on the test set were excellent, 0.89 for ACI-TIPI and 0.84 for the e-ACI-TIPI, as was calibration. On the national electrocardiographic database, ROC areas were 0.78 and 0.69, respectively, and with very good calibration. When tested for detection of patients with > 75% ACS probability, both electrocardiograph-based methods identified eligible patients well, and better than did EHRs.
Using data from medical devices such as electrocardiographs may provide accurate projections of available cohorts for clinical trials.
The value of the nosological distinction between non-affective and affective psychosis has frequently been challenged. We aimed to investigate the transdiagnostic dimensional structure and associated characteristics of psychopathology at First Episode Psychosis (FEP). Regardless of diagnostic categories, we expected that positive symptoms occurred more frequently in ethnic minority groups and in more densely populated environments, and that negative symptoms were associated with indices of neurodevelopmental impairment.
This study included 2182 FEP individuals recruited across six countries, as part of the EUropean network of national schizophrenia networks studying Gene–Environment Interactions (EU-GEI) study. Symptom ratings were analysed using multidimensional item response modelling in Mplus to estimate five theory-based models of psychosis. We used multiple regression models to examine demographic and context factors associated with symptom dimensions.
A bifactor model, composed of one general factor and five specific dimensions of positive, negative, disorganization, manic and depressive symptoms, best-represented associations among ratings of psychotic symptoms. Positive symptoms were more common in ethnic minority groups. Urbanicity was associated with a higher score on the general factor. Men presented with more negative and less depressive symptoms than women. Early age-at-first-contact with psychiatric services was associated with higher scores on negative, disorganized, and manic symptom dimensions.
Our results suggest that the bifactor model of psychopathology holds across diagnostic categories of non-affective and affective psychosis at FEP, and demographic and context determinants map onto general and specific symptom dimensions. These findings have implications for tailoring symptom-specific treatments and inform research into the mood-psychosis spectrum.
At the QEII Health Sciences Centre Emergency Department (ED) in Halifax, Nova Scotia, advanced care paramedics (ACPs) perform procedural sedation and analgesia (PSA) for many indications, including orthopedic procedures. We have begun using ACPs as sedationists for emergent upper gastrointestinal (UGI) endoscopy. This study compares ACP-performed ED PSA for UGI endoscopy and orthopedic procedures in terms of adverse events, airway intervention, vasopressor requirement, and PSA medication use.
A data set was built from an ED PSA quality control database matching 61 UGI endoscopy PSAs to 183 orthopedic PSAs by propensity scores calculated using age, gender, and the American Society of Anesthesiologists (ASA) classification. Outcomes assessed were hypotension (systolic BP<100 mm Hg or a 15% decrease from baseline), hypoxia (SaO2<90%), apnea (>30 sec), vomiting, arrhythmias, death, airway intervention, vasopressor requirement, and PSA medication use.
UGI endoscopy patients experienced hypotension more frequently than orthopedic patients (OR=4.11, CI: 2.05-8.22) and required airway repositioning less often (OR=0.24, CI: 0.10-0.59). They received ketamine more frequently (OR=15.7, CI: 4.75-67.7) and fentanyl less often (OR=0.30, CI: 0.15-0.63) than orthopedic patients. Four endoscopy patients received phenylephrine, and one required intubation. No patient died in either group.
In ACP-led sedation for UGI endoscopy and orthopedic procedures, adverse events were rare with the notable exception of hypotension, which was more frequent in the endoscopy group. Only endoscopy patients required vasopressor treatment and intubation. We provide preliminary evidence that ACPs can manage ED PSA for emergent UGI endoscopy, although priorities must shift from pain control to hemodynamic optimization.
OBJECTIVES/SPECIFIC AIMS: Nonalcoholic fatty liver disease (NAFLD) is the most common cause of liver disease in the United States and increases risk for cirrhosis and liver cancer. Identifying modifiable risk factors for NAFLD could allow better targeting of prevention programs. Insulin resistance (IR) plays a significant role in the development and progression of NAFLD. IR is also an important precursor to the development of type 2 diabetes (T2DM). However, the development and duration of IR during young adulthood and its association with NAFLD and T2DM in midlife is unclear. To test whether trajectories of IR using homeostatic model assessment (HOMA-IR) change throughout early adulthood are associated with risk of prevalent NAFLD and T2DM among persons with NAFLD in midlife independent of current or baseline HOMA-IR. METHODS/STUDY POPULATION: Participants from the CARDIA study, a prospective multicenter population-based biracial cohort of adults (baseline age 18–30 years), underwent HOMA-IR measurement (≥8 h fasting and not pregnant) at baseline (1985–1986) and follow-up exam years 7, 10, 15, 20, and 25. At Year 25 (Y25, 2010–2011), liver fat was assessed by noncontrast computed tomography (CT). NAFLD was defined as CT liver attenuation <51 Hounsfield Units after exclusion of other causes of liver fat (alcohol/hepatitis/medications). Latent mixture modeling was used to identify 25-year trajectories in HOMA-IR over time. Multivariable logistic regression models were used to assess associations between HOMA-IR trajectory groups and prevalent NAFLD with adjustment for baseline or Y25 HOMA-IR. RESULTS/ANTICIPATED RESULTS: Among 3060 participants, we identified 3 distinct trajectory groups for HOMA-IR for individuals free from diabetes in middle adulthood: qualitatively low-stable (46.7% of the cohort), moderate-increasing (42.0%), and high-increasing (11.3%) with a NAFLD prevalence at Y25 of: 8.3%, 33.4%, and 63.5%, respectively (p-trend<0.0001). After adjustment for confounders (baseline smoking status, alcohol use, body mass index, physical activity score, systolic blood pressure, antihypertensive medication use, and total/HDL cholesterol ratio) and baseline HOMA-IR, increasing HOMA-IR trajectories were associated with greater NAFLD prevalence compared with the low-stable trajectory group [odds ratio (95% CI): 5.8 (4.3–7.9) and 22.3 (14.2–34.9) for moderate and high, respectively]. These associations were attenuated, but remained significant, even after controlling for current Y25 HOMA-IR [OR=3.6 (2.6–5.0) for moderate and 5.9 (3.4–10.3) for high (referent: low)]. Among participants with NAFLD (n=511), high-increasing HOMA-IR trajectory was associated with greater prevalent [OR=6.5 (1.6–25.7)] and incident [OR=8.7 (2.2–34.4)] T2DM at Y25 independent of confounders and Y25 HOMA-IR (referent: low-stable). DISCUSSION/SIGNIFICANCE OF IMPACT: In this community-based sample of individuals free from diabetes at baseline, an increasing HOMA-IR trajectory through young adulthood was associated with greater NAFLD prevalence in midlife. Knowledge of changes in IR throughout adulthood provides new information on the risk of T2DM among persons with NAFLD in midlife independent of current level of IR. These findings highlight early identification of increasing IR as a potential target for primary prevention of T2DM in the setting of NAFLD.
The purpose of this study was to quantify the effect of multidrug-resistant (MDR) gram-negative bacteria and methicillin-resistant Staphylococcus aureus (MRSA) healthcare-associated infections (HAIs) on mortality following infection, regardless of patient location.
We conducted a retrospective cohort study of patients with an inpatient admission in the US Department of Veterans Affairs (VA) system between October 1, 2007, and November 30, 2010. We constructed multivariate log-binomial regressions to assess the impact of a positive culture on mortality in the 30- and 90-day periods following the first positive culture, using a propensity-score–matched subsample.
Patients identified with positive cultures due to MDR Acinetobacter (n=218), MDR Pseudomonas aeruginosa (n=1,026), and MDR Enterobacteriaceae (n=3,498) were propensity-score matched to 14,591 patients without positive cultures due to these organisms. In addition, 3,471 patients with positive cultures due to MRSA were propensity-score matched to 12,499 patients without positive MRSA cultures. Multidrug-resistant gram-negative bacteria were associated with a significantly elevated risk of mortality both for invasive (RR, 2.32; 95% CI, 1.85–2.92) and noninvasive cultures (RR, 1.33; 95% CI, 1.22–1.44) during the 30-day period. Similarly, patients with MRSA HAIs (RR, 2.77; 95% CI, 2.39–3.21) and colonizations (RR, 1.32; 95% CI, 1.22–1.50) had an increased risk of death at 30 days.
We found that HAIs due to gram-negative bacteria and MRSA conferred significantly elevated 30- and 90-day risks of mortality. This finding held true both for invasive cultures, which are likely to be true infections, and noninvasive infections, which are possibly colonizations.
Second-generation antipsychotics have been thought to cause fewer
extrapyramidal side-effects (EPS) than first-generation antipsychotics,
but recent pragmatic trials have indicated equivalence.
To determine whether second-generation antipsychotics had better outcomes
in terms of EPS than first-generation drugs.
We conducted an intention-to-treat, secondary analysis of data from an
earlier randomised controlled trial (n = 227). A
clinically significant difference was defined as double or half the
symptoms in groups prescribed first- v.
second-generation antipsychotics, represented by odds ratios greater than
2.0 (indicating advantage for first-generation drugs) or less than 0.5
(indicating advantage for the newer drugs). We also examined EPS in terms
of symptoms emergent at 12 weeks and 52 weeks, and symptoms that had
resolved at these time points.
At baseline those randomised to the first-generation antipsychotic group
(n = 118) had similar EPS to the second-generation
group (n = 109). Indications of resolved Parkinsonism
(OR = 0.5) and akathisia (OR = 0.4) and increased tardive dyskinesia (OR
= 2.2) in the second-generation drug group at 12 weeks were not
statistically significant and the effects were not present by 52 weeks.
Patients in the second-generation group were dramatically (30-fold) less
likely to be prescribed adjunctive anticholinergic medication, despite
equivalence in terms of EPS.
The expected improvement in EPS profiles for participants randomised to
second-generation drugs was not found; the prognosis over 1 year of those
in the first-generation arm was no worse in these terms. The place of
careful prescription of first-generation drugs in contemporary practice
remains to be defined, potentially improving clinical effectiveness and
avoiding life-shortening metabolic disturbances in some patients
currently treated with the narrow range of second-generation
antipsychotics used in routine practice. This has educational
implications because a generation of psychiatrists now has little or no
experience with first-generation antipsychotic prescription.
As device sizes are scaled down nearly to their atomic limits, the development of economically viable methods which may continue to improve device performance in accordance with Moore’s Law becomes ever more challenging. The recently developed technique of Electroplate-and-Lift (E&L) lithography promises to be an inexpensive, widely applicable method for the reproducible, controlled fabrication of micro- and nanostructures. In this study, E&L is applied to the fabrication of patterned copper micro- and nanowires as a model system. Copper wires with diameters ranging from 10 m to 200 nm have been produced using a single ultrananocrystalline diamond (UNCD)TM template, by varying only the electroplating time.
To quantify the relationship between copper wire diameter and deposition time, wires were electroplated at -0.4 V vs. the saturated calomel electrode (SCE) for durations between 2.5 and 160 s, then imaged by optical microscopy and/or scanning electron microscopy (SEM). Images were analyzed by identifying wire segments with ImageJ and examining the statistical distribution of wire diameters using Excel. This analysis verified theoretical predictions of a linear dependence between mean wire diameter and the square root of growth time.