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Models of cation exchange mechanisms and driving forces have proven effective predictors of clay behavior and chemistry, but are largely theoretical, particularly in complex systems involving high ionic strength brines or systems where hydration is controlled by relative humidity. In arid and cold environments, such as Mars, cyclical relative humidity variations may play a role in chemical alteration, particularly if clay minerals such as smectite are in the presence of salts. This study examines the effects of relative humidity on smectite-salt mixtures using environmental scanning electron microscopy (ESEM) to observe the physiochemical effects of salt deliquescence and desiccation on smectite textures and elemental distributions. Results demonstrate that even reaction periods as short as a few minutes allow ample time for relative humidity to affect the smectite-salt mixtures. In addition to smectite swelling and salt deliquescence, we also observed rapid changes in element distributions within the smectite and new crystal growth in the presence of high relative humidity. Even in the absence of bulk liquid water, exchangeable cations migrated out of the smectite and formed new crystals at the smectite-salt interface. The observed microscopic changes in elemental distributions indicate that the migration of cations driven by cation exchange led to secondary mineral precipitation, likely a CaSO4 mineral, within a sub-micrometer-thick layer of water on the smectite grains. The results of this study demonstrate that during periods of elevated relative humidity, active smectite mineral alteration and secondary mineral precipitation may be possible on present-day Mars where salts and smectites are in direct physical contact.
We sought to validate available tools for predicting recurrent C. difficile infection (CDI) including recurrence risk scores (by Larrainzar-Coghen, Reveles, D’Agostino, Cobo, and Eyre et al) alongside consensus guidelines risk criteria, the leading severity score (ATLAS), and PCR cycle threshold (as marker of fecal organism burden) using electronic medical records.
Design:
Retrospective cohort study validating previously described tools.
Setting:
Tertiary care academic hospital.
Patients:
Hospitalized adult patients with CDI at University of Virginia Medical Center.
Methods:
Risk scores were calculated within ±48 hours of index CDI diagnosis using a large retrospective cohort of 1,519 inpatient infections spanning 7 years and compared using area under the receiver operating characteristic curve (AUROC) and the DeLong test. Recurrent CDI events (defined as a repeat positive test or symptom relapse within 60 days requiring retreatment) were confirmed by clinician chart review.
Results:
Reveles et al tool achieved the highest AUROC of 0.523 (and 0.537 among a subcohort of 1,230 patients with their first occurrence of CDI), which was not substantially better than other tools including the current IDSA/SHEA C. difficile guidelines or PCR cycle threshold (AUROC: 0.564), regardless of prior infection history.
Conclusions:
All tools performed poorly for predicting recurrent C. difficile infection (AUROC range: 0.488–0.564), especially among patients with a prior history of infection (AUROC range: 0.436–0.591). Future studies may benefit from considering novel biomarkers and/or higher-dimensional models that could augment or replace existing tools that underperform.
OBJECTIVES/GOALS: To tackle population-level health disparities, quality dashboards can leverage individual socioeconomic status (SES) measures, which are not always readily accessible. This study aimed to assess the feasibility of a population health management strategy for colorectal cancer (CRC) screening rates using the HOUSES index and heatmap analysis. METHODS/STUDY POPULATION: We applied the 2019 Minnesota Community Measurement data for optimal CRC screening to eligible Mayo Clinic Midwest panel patients. SES was defined by HOUSES index, a validated SES measure based on publicly available property data for the U.S. population. We first assessed the association of suboptimal CRC screening rate with HOUSES index adjusting for age, sex, race/ethnicity, comorbidity, and Zip-code level deprivation by using a mixed effects logistic regression model. We then assessed changes in ranking for performance of individual clinics (i.e., % of patients with optimal CRC screening rate) before and after adjusting for HOUSES index. Geographical hotspots of high proportions of low SES AND high proportions of suboptimal CRC screening were superimposed to identify target population for outreach. RESULTS/ANTICIPATED RESULTS: A total of 58,382 adults from 41 clinics were eligible for CRC screening assessment in 2019 (53% Female). Patients with lower SES defined by HOUSES quartile 1-3 have significantly lower CRC screening compared to those with highest SES (HOUSES quartile 4) (adj. OR [95% CI]: 0.52 [0.50-0.56] for Q1, 0.66 [0.62-0.70] for Q2, and 0.81 [0.76-0.85]) for Q3). Ranking of 26 out of 41 (63%) clinics went down after adjusting for HOUSES index suggesting disproportionately higher proportion of underserved patients with suboptimal CRC screening. We were able to successfully identify hotspots of suboptimal CRC (area with greater than 130% of expected value) and overlay with higher proportion of underserved population (HOUSES Q1), which can be used for data-driven targeted interventions such as mobile health clinics. DISCUSSION/SIGNIFICANCE: HOUSES index and associated heatmap analysis can contribute to advancing health equity. This approach can aid health care organizations in meeting the newly established standards by The Joint Commission, which have elevated health equity to a national safety priority.
To evaluate the economic costs of reducing the University of Virginia Hospital’s present “3-negative” policy, which continues methicillin-resistant Staphylococcus aureus (MRSA) contact precautions until patients receive 3 consecutive negative test results, to either 2 or 1 negative.
Design:
Cost-effective analysis.
Settings:
The University of Virginia Hospital.
Patients:
The study included data from 41,216 patients from 2015 to 2019.
Methods:
We developed a model for MRSA transmission in the University of Virginia Hospital, accounting for both environmental contamination and interactions between patients and providers, which were derived from electronic health record (EHR) data. The model was fit to MRSA incidence over the study period under the current 3-negative clearance policy. A counterfactual simulation was used to estimate outcomes and costs for 2- and 1-negative policies compared with the current 3-negative policy.
Results:
Our findings suggest that 2-negative and 1-negative policies would have led to 6 (95% CI, −30 to 44; P < .001) and 17 (95% CI, −23 to 59; −10.1% to 25.8%; P < .001) more MRSA cases, respectively, at the hospital over the study period. Overall, the 1-negative policy has statistically significantly lower costs ($628,452; 95% CI, $513,592–$752,148) annually (P < .001) in US dollars, inflation-adjusted for 2023) than the 2-negative policy ($687,946; 95% CI, $562,522–$812,662) and 3-negative ($702,823; 95% CI, $577,277–$846,605).
Conclusions:
A single negative MRSA nares PCR test may provide sufficient evidence to discontinue MRSA contact precautions, and it may be the most cost-effective option.
The coefficient of friction of clay minerals at the micro-scale has generally not been studied due to difficulties in obtaining measurements in a bulk-soil volume undergoing shear at such small scales. Information on friction at the micro-scale may provide insight into grain-scale processes that operate in bulk samples or in natural faults. The objective of this study was to develop a method to measure the microscale friction coefficient of smectites. The experiments described show that the axial atomic force microscopy method can be adapted to easily obtain accurate coefficient of friction (μ) measurements for smectites from force curves involving colloidal probes. The method allows for the measurements to be performed over spatial scales of a few μm, can be carried out under dry conditions or a wide range of aqueous solutions, and requires no calibration beyond making a few microscopic measurements of the probe. This method provides measurements of micro-scale normal and shear forces between minerals, which can be used for a variety of applications such as the study of shear deformation, consolidation, and fault dynamics. Control tests of silica on mica (μ = 0.29±0.02) agree with literature values where limits indicate one standard deviation. Coefficient of friction values for wet and dry Na-montmorillonite were determined to be 0.20±0.03 and 0.72±0.03, respectively.
Nontronite NAu-1 was exposed to moderate temperature and pressure conditions (250 and 300°C at 100 MPa pressure) in KCl brine to simulate burial diagenetic systems over accelerated time periods appropriate for laboratory experiments. Powder X-ray diffraction and transmission electron microscopy analysis of the coexisting mixed-layer and discrete 10 Å clay reaction products, and inductively coupled plasma-mass spectrometry analysis of the remaining fluids, indicated that the clay retained octahedral Fe and was identified as Fe-celadonite. The release of Fe from smectite during burial diagenesis has been hypothesized as a mechanism for magnetite authigenesis. High Al activity relative to Fe may be critical to the formation of an aluminous illite and any associated authigenic magnetite.
Patients with psychiatric illness are at increased risk of developing non-psychiatric medical illnesses. There have been positive reports regarding the integration of primary care services into mental health facilities. Here, we evaluate the appropriateness of psychiatry non-consultant hospital doctors (NCHD) transfers to the local emergency department (ED) in the context of an in-house primary care service.
Methods.
We reviewed the inpatient transfers from St Patrick’s University Hospital (SPUH) to the local ED at St James’ Hospital (SJH) from 1 January 2016 to 31 December 2017. We used inpatient admission to SJH as our primary marker of an appropriate transfer.
Results.
246 inpatients were transferred from SPUH to the SJH ED for medical review in the years 2016 and 2017. 27 (11%) of these were referred to the ED by the primary care service. 51% of those referred were admitted with similar rates of admission for both general practitioner (n = 27, 54% admitted) and NCHD initiated referrals (n = 219, 51% admitted). Acute neurological illness, concern regarding a cardiac illness, and deliberate self-harm were the most common reasons for referral.
Conclusion.
Our primary finding is that, of those transferred to ED by either primary care or a psychiatry NCHD, a similar proportion was judged to be in need of inpatient admission. This indicates that as a group, psychiatry NCHD assessment of acuity and need for transfer was similar to that of their colleagues in primary care.
With the recent discovery of a dozen dusty star-forming galaxies and around 30 quasars at z > 5 that are hyper-luminous in the infrared (μ LIR > 1013 L⊙, where μ is a lensing magnification factor), the possibility has opened up for SPICA, the proposed ESA M5 mid-/far-infrared mission, to extend its spectroscopic studies toward the epoch of reionisation and beyond. In this paper, we examine the feasibility and scientific potential of such observations with SPICA’s far-infrared spectrometer SAFARI, which will probe a spectral range (35–230 μm) that will be unexplored by ALMA and JWST. Our simulations show that SAFARI is capable of delivering good-quality spectra for hyper-luminous infrared galaxies at z = 5 − 10, allowing us to sample spectral features in the rest-frame mid-infrared and to investigate a host of key scientific issues, such as the relative importance of star formation versus AGN, the hardness of the radiation field, the level of chemical enrichment, and the properties of the molecular gas. From a broader perspective, SAFARI offers the potential to open up a new frontier in the study of the early Universe, providing access to uniquely powerful spectral features for probing first-generation objects, such as the key cooling lines of low-metallicity or metal-free forming galaxies (fine-structure and H2 lines) and emission features of solid compounds freshly synthesised by Population III supernovae. Ultimately, SAFARI’s ability to explore the high-redshift Universe will be determined by the availability of sufficiently bright targets (whether intrinsically luminous or gravitationally lensed). With its launch expected around 2030, SPICA is ideally positioned to take full advantage of upcoming wide-field surveys such as LSST, SKA, Euclid, and WFIRST, which are likely to provide extraordinary targets for SAFARI.
Copper-impregnated surfaces and linens have been shown to reduce infections and multidrug-resistant organism (MDRO) acquisition in healthcare settings. However, retrospective analyses of copper linen deployment at a 40-bed long-term acute-care hospital demonstrated no significant reduction in incidences of healthcare facility-onset Clostridium difficile infection or MDRO acquisition.
Measurements in the infrared wavelength domain allow direct assessment of the physical state and energy balance of cool matter in space, enabling the detailed study of the processes that govern the formation and evolution of stars and planetary systems in galaxies over cosmic time. Previous infrared missions revealed a great deal about the obscured Universe, but were hampered by limited sensitivity.
SPICA takes the next step in infrared observational capability by combining a large 2.5-meter diameter telescope, cooled to below 8 K, with instruments employing ultra-sensitive detectors. A combination of passive cooling and mechanical coolers will be used to cool both the telescope and the instruments. With mechanical coolers the mission lifetime is not limited by the supply of cryogen. With the combination of low telescope background and instruments with state-of-the-art detectors SPICA provides a huge advance on the capabilities of previous missions.
SPICA instruments offer spectral resolving power ranging from R ~50 through 11 000 in the 17–230 μm domain and R ~28.000 spectroscopy between 12 and 18 μm. SPICA will provide efficient 30–37 μm broad band mapping, and small field spectroscopic and polarimetric imaging at 100, 200 and 350 μm. SPICA will provide infrared spectroscopy with an unprecedented sensitivity of ~5 × 10−20 W m−2 (5σ/1 h)—over two orders of magnitude improvement over what earlier missions. This exceptional performance leap, will open entirely new domains in infrared astronomy; galaxy evolution and metal production over cosmic time, dust formation and evolution from very early epochs onwards, the formation history of planetary systems.
Prior research has documented shared heritable contributions to non-suicidal self-injury (NSSI) and suicidal ideation (SI) as well as NSSI and suicide attempt (SA). In addition, trauma exposure has been implicated in risk for NSSI and suicide. Genetically informative studies are needed to determine common sources of liability to all three self-injurious thoughts and behaviors, and to clarify the nature of their associations with traumatic experiences.
Methods
Multivariate biometric modeling was conducted using data from 9526 twins [59% female, mean age = 31.7 years (range 24–42)] from two cohorts of the Australian Twin Registry, some of whom also participated in the Childhood Trauma Study and the Nicotine Addiction Genetics Project.
Results
The prevalences of high-risk trauma exposure (HRT), NSSI, SI, and SA were 24.4, 5.6, 27.1, and 4.6%, respectively. All phenotypes were moderately to highly correlated. Genetic influences on self-injurious thoughts and behaviors and HRT were significant and highly correlated among men [rG = 0.59, 95% confidence interval (CI) (0.37–0.81)] and women [rG = 0.56 (0.49–0.63)]. Unique environmental influences were modestly correlated in women [rE = 0.23 (0.01–0.45)], suggesting that high-risk trauma may confer some direct risk for self-injurious thoughts and behaviors among females.
Conclusions
Individuals engaging in NSSI are at increased risk for suicide, and common heritable factors contribute to these associations. Preventing trauma exposure may help to mitigate risk for self-harm and suicide, either directly or indirectly via reductions in liability to psychopathology more broadly. In addition, targeting pre-existing vulnerability factors could significantly reduce risk for life-threatening behaviors among those who have experienced trauma.
We hypothesized that a computerized clinical decision support tool for Clostridium difficile testing would reduce unnecessary inpatient tests, resulting in fewer laboratory-identified events. Census-adjusted interrupted time-series analyses demonstrated significant reductions of 41% fewer tests and 31% fewer hospital-onset C. difficile infection laboratory-identified events following this intervention.
The SPICA mid- and far-infrared telescope will address fundamental issues in our understanding of star formation and ISM physics in galaxies. A particular hallmark of SPICA is the outstanding sensitivity enabled by the cold telescope, optimised detectors, and wide instantaneous bandwidth throughout the mid- and far-infrared. The spectroscopic, imaging, and polarimetric observations that SPICA will be able to collect will help in clarifying the complex physical mechanisms which underlie the baryon cycle of galaxies. In particular, (i) the access to a large suite of atomic and ionic fine-structure lines for large samples of galaxies will shed light on the origin of the observed spread in star-formation rates within and between galaxies, (ii) observations of HD rotational lines (out to ~10 Mpc) and fine structure lines such as [C ii] 158 μm (out to ~100 Mpc) will clarify the main reservoirs of interstellar matter in galaxies, including phases where CO does not emit, (iii) far-infrared spectroscopy of dust and ice features will address uncertainties in the mass and composition of dust in galaxies, and the contributions of supernovae to the interstellar dust budget will be quantified by photometry and monitoring of supernova remnants in nearby galaxies, (iv) observations of far-infrared cooling lines such as [O i] 63 μm from star-forming molecular clouds in our Galaxy will evaluate the importance of shocks to dissipate turbulent energy. The paper concludes with requirements for the telescope and instruments, and recommendations for the observing strategy.
IR spectroscopy in the range 12–230 μm with the SPace IR telescope for Cosmology and Astrophysics (SPICA) will reveal the physical processes governing the formation and evolution of galaxies and black holes through cosmic time, bridging the gap between the James Webb Space Telescope and the upcoming Extremely Large Telescopes at shorter wavelengths and the Atacama Large Millimeter Array at longer wavelengths. The SPICA, with its 2.5-m telescope actively cooled to below 8 K, will obtain the first spectroscopic determination, in the mid-IR rest-frame, of both the star-formation rate and black hole accretion rate histories of galaxies, reaching lookback times of 12 Gyr, for large statistically significant samples. Densities, temperatures, radiation fields, and gas-phase metallicities will be measured in dust-obscured galaxies and active galactic nuclei, sampling a large range in mass and luminosity, from faint local dwarf galaxies to luminous quasars in the distant Universe. Active galactic nuclei and starburst feedback and feeding mechanisms in distant galaxies will be uncovered through detailed measurements of molecular and atomic line profiles. The SPICA’s large-area deep spectrophotometric surveys will provide mid-IR spectra and continuum fluxes for unbiased samples of tens of thousands of galaxies, out to redshifts of z ~ 6.
The physical processes driving the chemical evolution of galaxies in the last ~ 11Gyr cannot be understood without directly probing the dust-obscured phase of star-forming galaxies and active galactic nuclei. This phase, hidden to optical tracers, represents the bulk of the star formation and black hole accretion activity in galaxies at 1 < z < 3. Spectroscopic observations with a cryogenic infrared observatory like SPICA, will be sensitive enough to peer through the dust-obscured regions of galaxies and access the rest-frame mid- to far-infrared range in galaxies at high-z. This wavelength range contains a unique suite of spectral lines and dust features that serve as proxies for the abundances of heavy elements and the dust composition, providing tracers with a feeble response to both extinction and temperature. In this work, we investigate how SPICA observations could be exploited to understand key aspects in the chemical evolution of galaxies: the assembly of nearby galaxies based on the spatial distribution of heavy element abundances, the global content of metals in galaxies reaching the knee of the luminosity function up to z ~ 3, and the dust composition of galaxies at high-z. Possible synergies with facilities available in the late 2020s are also discussed.
The current study examined a stage-based alcohol use trajectory model to test for potential causal effects of earlier drinking milestones on later drinking milestones in a combined sample of two cohorts of Australian monozygotic and same-sex dizygotic twins (N = 7,398, age M = 30.46, SD = 2.61, 61% male, 56% monozygotic twins). Ages of drinking, drunkenness, regular drinking, tolerance, first nontolerance alcohol use disorder symptom, and alcohol use disorder symptom onsets were assessed retrospectively. Ages of milestone attainment (i.e., age-of-onset) and time between milestones (i.e., time-to-event) were examined via frailty models within a multilevel discordant twin design. For age-of-onset models, earlier ages of onset of antecedent drinking milestones increased hazards for earlier ages of onset for more proximal subsequent drinking milestones. For the time-to-event models, however, earlier ages of onset for the “starting” milestone decreased risk for a shorter time period between the starting and the “ending” milestone. Earlier age of onset of intermediate milestones between starting and ending drinking milestones had the opposite effect, increasing risk for a shorter time period between the starting and ending milestones. These results are consistent with a causal effect of an earlier age of drinking milestone onset on temporally proximal subsequent drinking milestones.
Migraine frequently co-occurs with depression. Using a large sample of Australian twin pairs, we aimed to characterize the extent to which shared genetic factors underlie these two disorders. Migraine was classified using three diagnostic measures, including self-reported migraine, the ID migraine™ screening tool, or migraine without aura (MO) and migraine with aura (MA) based on International Headache Society (IHS) diagnostic criteria. Major depressive disorder (MDD) and minor depressive disorder (MiDD) were classified using the Diagnostic and Statistical Manual of Mental Disorders (DSM) criteria. Univariate and bivariate twin models, with and without sex-limitation, were constructed to estimate the univariate and bivariate variance components and genetic correlation for migraine and depression. The univariate heritability of broad migraine (self-reported, ID migraine, or IHS MO/MA) and broad depression (MiDD or MDD) was estimated at 56% (95% confidence interval [CI]: 53–60%) and 42% (95% CI: 37–46%), respectively. A significant additive genetic correlation (rG = 0.36, 95% CI: 0.29–0.43) and bivariate heritability (h2 = 5.5%, 95% CI: 3.6–7.8%) was observed between broad migraine and depression using the bivariate Cholesky model. Notably, both the bivariate h2 (13.3%, 95% CI: 7.0–24.5%) and rG (0.51, 95% CI: 0.37–0.69) estimates significantly increased when analyzing the more narrow clinically accepted diagnoses of IHS MO/MA and MDD. Our results indicate that for both broad and narrow definitions, the observed comorbidity between migraine and depression can be explained almost entirely by shared underlying genetically determined disease mechanisms.
Objectives: This research examined the familial aggregation of migraine, depression, and their co-occurrence.
Methods: Diagnoses of migraine and depression were determined in a sample of 5,319 Australian twins. Migraine was diagnosed by either self-report, the ID migraine™ Screener, or International Headache Society (IHS) criteria. Depression was defined by fulfilling either major depressive disorder (MDD) or minor depressive disorder (MiDD) based on the Diagnostic and Statistical Manual of Mental Disorders (DSM) criteria. The relative risks (RR) for migraine and depression were estimated in co-twins of twin probands reporting migraine or depression to evaluate their familial aggregation and co-occurrence.
Results: An increased RR of both migraine and depression in co-twins of probands with the same trait was observed, with significantly higher estimates within monozygotic (MZ) twin pairs compared to dizygotic (DZ) twin pairs. For cross-trait analysis, the RR for migraine in co-twins of probands reporting depression was 1.36 (95% CI: 1.24–1.48) in MZ pairs and 1.04 (95% CI: 0.95–1.14) in DZ pairs; and the RR for depression in co-twins of probands reporting migraine was 1.26 (95% CI: 1.14–1.38) in MZ pairs and 1.02 (95% CI: 0.94–1.11) in DZ pairs. The RR for strict IHS migraine in co-twins of probands reporting MDD was 2.23 (95% CI: 1.81–2.75) in MZ pairs and 1.55 (95% CI: 1.34–1.79) in DZ pairs; and the RR for MDD in co-twins of probands reporting IHS migraine was 1.35 (95% CI: 1.13–1.62) in MZ pairs and 1.06 (95% CI: 0.93–1.22) in DZ pairs.
Conclusions: We observed significant evidence for a genetic contribution to familial aggregation of migraine and depression. Our findings suggest a bi-directional association between migraine and depression, with an increased risk for depression in relatives of probands reporting migraine, and vice versa. However, the observed risk for migraine in relatives of probands reporting depression was considerably higher than the reverse. These results add further support to previous studies suggesting that patients with comorbid migraine and depression are genetically more similar to patients with only depression than patients with only migraine.