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Posttraumatic stress disorder (PTSD) is the most highly co-occurring psychiatric disorder among veterans with cannabis use disorder (CUD). Despite some evidence that cannabis use prospectively exacerbates the course of PTSD, which in turn increases the risk for CUD, the causal nature of the relationship between cannabis and psychiatric comorbidity is debated. The longitudinal relationship between PTSD diagnosis and traumatic intrusion symptoms with cannabis use and CUD was examined using cross-lagged panel model (CLPM) analysis.
Prospective data from a longitudinal observational study of 361 veterans deployed post-9/11/2001 included PTSD and CUD diagnoses, cannabis use, and PTSD-related traumatic intrusion symptoms from the Inventory of Depression and Anxiety Symptoms.
A random intercept CLPM analysis that leveraged three waves (baseline, 6 months and 12 months) of cannabis use and PTSD-related intrusion symptoms to account for between-person differences found that baseline cannabis use was significantly positively associated with 6-month intrusion symptoms; the converse association was significant but reduced in magnitude (baseline use to 6-month intrusions: β = 0.46, 95% CI 0.155–0.765; baseline intrusions to 6-month use: β = 0.22, 95% CI −0.003 to 0.444). Results from the two-wave CLPM reveal a significant effect from baseline PTSD to 12-month CUD (β = 0.15, 95% CI 0.028–0.272) but not from baseline CUD to 12-month PTSD (β = 0.12, 95% CI −0.022 to 0.262).
Strong prospective associations capturing within-person changes suggest that cannabis use is linked with greater severity of trauma-related intrusion symptoms over time. A strong person-level directional association between PTSD and CUD was evident. Findings have significant clinical implications for the long-term effects of cannabis use among individuals with PTSD.
Prior research has shown that sipping of alcohol begins to emerge during childhood and is potentially etiologically significant for later substance use problems. Using a large, community sample of 9- and 10-year-olds (N = 11,872; 53% female), we examined individual differences in precocious alcohol use in the form of alcohol sipping. We focused explicitly on features that are robust and well-demonstrated correlates of, and antecedents to, alcohol excess and related problems later in the lifespan, including youth- and parent-reported externalizing traits (i.e., impulsivity, behavioral inhibition and activation) and psychopathology. Seventeen percent of the sample reported sipping alcohol outside of a religiously sanctioned activity by age 9 or 10. Several aspects of psychopathology and personality emerged as small but reliable correlates of sipping. Nonreligious sipping was related to youth-reported impulsigenic traits, aspects of behavioral activation, prodromal psychotic-like symptoms, and mood disorder diagnoses, as well as parent-reported externalizing disorder diagnoses. Religious sipping was unexpectedly associated with certain aspects of impulsivity. Together, our findings point to the potential importance of impulsivity and other transdiagnostic indicators of psychopathology (e.g., emotion dysregulation, novelty seeking) in the earliest forms of drinking behavior.
The rapid cycling variant of bipolar disorder is defined as the occurrence of four periods of either manic or depressive illness within 12 months. Patients suffering from this variant of bipolar disorder have an unmet need for effective treatment. This review examines two major studies in an attempt to update understanding of the current therapies available to treat rapid cycling patients. The first trial compares lamotrigine versus placebo in 182 patients studied for 6 months. The second is a recently completed, 20-month trial comparing divalproate and lithium in 60 patients. Both trials had a double-blind, randomized parallel-group design. The data from the latter study indicate that there are no large differences in efficacy between lithium and divalproate in the long-term treatment of rapid cycling bipolar disorder. In addition, lamotrigine has the potential to complement the spectrum of lithium and divalproate through its greater efficacy for depressive symptoms.
The need for integration of maternal mental health into primary health care (PHC) is well documented. However, research evidence suggest that maternal depression still remains uderrecognized and untreated. The help seeking bevaviour of mothers with depression remains an insufficiently investigated issue.
The present qualitative study’s objective has been to investigate, identify and interpret the help seeking behavior of mothers of young children experiencing depressive symptoms.
Our aim was to inform policies and practices so as to improve the detection and management of maternal depression within the primary health care, in particular in countries of weak PHC systems and limited resources.
Thirty semi-structured interviews were conducted to a purposeful sample of thirty mothers living in Athens. The selection of participants’ was based on socioeconomic status and depression severity. Qualitative content analysis was conducted independently by two researchers.
Two broad themes influencing mothers’ help seeking behavior were identified. Barriers and enablers related to PHC system aspects and psychosocial factors emerged. Barriers were associated to several aspects of the weak PHC system, such as the fragmentation of services, the lack of team based care, but also the perceived low quality and availability of community mental health services. The main psychosocial factors identified were stigma related issues, unfavorable attitudes toward mental health, and perceived social expectations regarding the mothering role.
Apart from the psychosocial factors, several aspects of the weak primary health care system could mediate the help seeking behavior of mothers experiencing depressive symptoms.
To explore if better diet quality scores as a measure of adherence to the Australian Dietary Guidelines (ADG) and the Mediterranean diet (MedDiet) are associated with a lower incidence of hypertension and non-fatal CVD.
Prospective analysis of the 1946–1951 cohort of the Australian Longitudinal Study on Women’s Health (ALSWH). The Australian Recommended Foods Score (ARFS) was calculated as an indicator of adherence to the ADG; the Mediterranean Diet Score (MDS) measured adherence to the MedDiet. Outcomes included hypertension and non-fatal CVD. Generalised estimating equations estimated OR and 95 % CI across quartiles of diet quality scores.
1946–1951 cohort of the ALSWH (n 5324), without CVD, hypertension and diabetes at baseline (2001), with complete FFQ data.
There were 1342 new cases of hypertension and 629 new cases of non-fatal CVD over 15 years of follow-up. Multivariate analysis indicated that women reporting better adherence to the ARFS (≥38/74) had 15 % (95 % CI 1, 28 %; P = 0·05) lower odds of hypertension and 46 % (95 % CI 6, 66 %; P = 0·1) lower odds of non-fatal CVD. Women reporting better adherence to the MDS (≥8/17) had 27 % (95 % CI 15, 47 %; P = 0·0006) lower odds of hypertension and 30 % (95 % CI 2, 50 %; P = 0·03) lower odds of non-fatal CVD.
Better adherence to diet quality scores is associated with lower risk of hypertension and non-fatal CVD. These results support the need for updated evidenced based on the ADG as well as public health nutrition policies in Australia.
The consumption of nitrate-rich vegetables can acutely lower blood pressure and improve mediators shown to optimise vascular health. However, we do not yet understand the impact of long-term habitual dietary nitrate intake and its association with CVD. Therefore, the aim of this investigation was to examine the relationship between habitual dietary nitrate intakes and risk of CHD in women from the Nurses’ Health Study. We prospectively followed 62 535 women who were free from diabetes, CVD and cancer at baseline in 1986. Information on diet was updated every 4 years with validated FFQ. The main outcome was CHD defined by the occurrence of non-fatal myocardial infarction or fatal CHD. Cox proportional hazard regression models were used to estimate the relative risks (RR) and 95 % CI. During 26 years of follow-up, 2257 cases of CHD were identified. When comparing the highest quintile of nitrate intake with the lowest quintile, in aged-adjusted analysis there was a protective association for CHD (RR=0·77, 95 % CI 0·68, 0·97; P=0·0002) which dissipated after further adjustment for smoking, physical activity, BMI and race (RR=0·91; 95 % CI 0·80, 1·04; P=0·27). This magnitude of association was further attenuated once we adjusted for the Alternative Healthy Eating Index excluding vegetable and fruit consumption (RR=1·04, 95 % CI 0·91, 1·20; P=0·34). Dietary nitrate intake was not related to the risk of CHD after adjustment for other lifestyle and non-vegetable dietary factors in a large group of US women.
We study the shape and motion of gas bubbles in a liquid flowing through a horizontal or slightly inclined thin annulus. Experimental data show that in the horizontal annulus, bubbles develop a unique ‘tadpole-like’ shape with a semi-circular cap and a highly stretched tail. As the annulus is inclined, the bubble tail tends to vanish, resulting in a significant decrease of bubble length. To model the bubble evolution, the thin annulus is conceptualised as a ‘Hele-Shaw’ cell in a curvilinear space. The three-dimensional flow within the cell is represented by a gap-averaged, two-dimensional model, which achieved a close match to the experimental data. The numerical model is further used to investigate the effects of gap thickness and pipe diameter on the bubble behaviour. The mechanism for the semi-circular cap formation is interpreted based on an analogous irrotational flow field around a circular cylinder, based on which a theoretical solution to the bubble velocity is derived. The bubble motion and cap geometry is mainly controlled by the gravitational component perpendicular to the flow direction. The bubble elongation in the horizontal annulus is caused by the buoyancy that moves the bubble to the top of the annulus. However, as the annulus is inclined, the gravitational component parallel to the flow direction becomes important, causing bubble separation at the tail and reduction in bubble length.
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.
We evaluated and compared the completeness, timeliness, simplicity, usefulness and flexibility between the former National Tuberculosis (TB) Surveillance System (NTBSS) and the newer Computerised Infectious Disease Reporting System (CIDR). Completeness was assessed by examining the field completion of key variables and median time from diagnosis to notification was calculated to evaluate timeliness. Differences between the two systems on completeness and timeliness were statistically assessed using χ2 and Wilcoxon rank-sum test, respectively. An online questionnaire on simplicity, flexibility and usefulness was sent to key stakeholders. Time and diagnosis-related variables were more complete in NTBSS, while variables on drug susceptibility, HIV and laboratory tests were more complete in CIDR (P < 0.05). The median time notification interval increased significantly in CIDR (P < 0.05). Stakeholders thought that CIDR is simpler (37.5%), more useful (41.7%) and more flexible (29.2%) than NTBSS. This study demonstrated that CIDR did not improve data completeness and decreased timeliness of notification. Simplicity, usefulness and flexibility were improved but qualitative methods should be applied to further explore these results.
In rainfed lowland rice-based systems, increasing labour scarcity due to off-farm employment is encouraging farmers to switch from transplanting to dry direct seeding (DDS). To assure stable productivity at a level comparable with or superior to transplanting, DDS management must ensure rice seedlings have access to nutrients in order to be competitive with weeds, which must also be suppressed. This paper examined farmer perceptions of DDS using a farmer survey, and used on-farm experiments to examine responses of rainfed lowland rice to integrated nutrient–weed management, based around mechanised DDS. In the survey, weeds were the biggest problem faced by farmers in using DDS (61%). In 90% of cases, farmers reported that weeds had increased under DDS, with most farmers (78%) controlling weeds by hand. All farmers said they would use DDS in the following season (100%), due to labour savings (47%), timeliness of operations, improved productivity, low investment or a combination of these (44%). In on-farm experiments, banding nutrients with the seed at sowing enhanced early dry matter of rice, while early weed dry matter was reduced. Early weed control using ducklings or hand weeding reduced weed competition and increased rice growth, with ducklings providing additional yield benefits over hand weeding. Early increases in seedling vigour of rice, and in weed suppression, carried through to greater dry matter and yield of rice at maturity. Integrated nutrient–weed management in mechanised DDS increased DDS yields, reduced DDS yield variability and contributed to sustainability of DDS rice systems.
To identify facilitators and barriers to implementation of a Clostridium difficile screening intervention among bone marrow transplant (BMT) patients and to evaluate the clinical effectiveness of the intervention on the rate of hospital-onset C. difficile infection (HO-CDI).
A 505-bed tertiary-care medical center
All 5,357 patients admitted to the BMT and general medicine wards from January 2014 to February 2017 were included in the study. Interview participants included 3 physicians, 4 nurses, and 4 administrators.
All BMT patients were screened within 48 hours of admission. Colonized patients, as defined by a C. difficile–positive polymerase chain reaction (PCR) stool result, were placed under contact precautions for the duration of their hospital stay.
Interview responses were coded according to the Systems Engineering Initiative for Patient Safety conceptual framework. We compared pre- and postintervention HO-CDI rates on BMT and general internal medicine units using time-series analysis.
Stakeholder engagement, at both the person and organizational level, facilitates standardization and optimization of intervention protocols. While the screening intervention was generally well received, tools and technology were sources of concern. The mean incidence of HO-CDI decreased on the BMT service postintervention (P<.0001). However, the effect of the change in the trend postintervention was not significantly different on BMT compared to the control wards (P=.93).
We report the first mixed-methods study to evaluate a C. difficile screening intervention among the BMT population. The positive nature by which the intervention was received by front-line clinical staff, laboratory staff, and administrators is promising for future implementation studies.
Propagation of a strong incident shock through a bed of particles results in complex wave dynamics such as a reflected shock, a transmitted shock, and highly unsteady flow inside the particle bed. In this paper we present three-dimensional numerical simulations of shock propagation in air over a random bed of particles. We assume the flow is inviscid and governed by the Euler equations of gas dynamics. Simulations are carried out by varying the volume fraction of the particle bed at a fixed shock Mach number. We compute the unsteady inviscid streamwise and transverse drag coefficients as a function of time for each particle in the random bed for different volume fractions. We show that (i) there are significant variations in the peak drag for the particles in the bed, (ii) the mean peak drag as a function of streamwise distance through the bed decreases with a slope that increases as the volume fraction increases, and (iii) the deviation from the mean peak drag does not correlate with local volume fraction. We also present the local Mach number and pressure contours for the different volume fractions to explain the various observed complex physical mechanisms occurring during the shock–particle interactions. Since the shock interaction with the random bed of particles leads to transmitted and reflected waves, we compute the average flow properties to characterize the strength of the transmitted and reflected shock waves and quantify the energy dissipation inside the particle bed. Finally, to better understand the complex wave dynamics in a random bed, we consider a simpler approximation of a planar shock propagating in a duct with a sudden area change. We obtain Riemann solutions to this problem, which are used to compare with fully resolved numerical simulations.
We present a variational optimization method that can identify the most efficient kinematic dynamo in a sphere, where efficiency is based on the value of a magnetic Reynolds number that uses enstrophy to characterize the inductive effects of the fluid flow. In this large-scale optimization, we restrict the flow to be steady and incompressible, and the boundary of the sphere to be no-slip and electrically insulating. We impose these boundary conditions using a Galerkin method in terms of specifically designed vector field bases. We solve iteratively for the flow field and the accompanying magnetic eigenfunction in order to find the minimal critical magnetic Reynolds number
for the onset of a dynamo. Although nonlinear, this iteration procedure converges to a single solution and there is no evidence that this is not a global optimum. We find that
is at least three times lower than that of any published example of a spherical kinematic dynamo generated by steady flows, and our optimal dynamo clearly operates above the theoretical lower bounds for dynamo action. The corresponding optimal flow has a spatially localized helical structure in the centre of the sphere, and the dominant components are invariant under rotation by
Whitehouse's theory on fusion can explain why suicide terrorists are willing to make the ultimate sacrifice for their groups, but the following questions on violent extremism remain: (a) Why are victims of suicide terrorism often innocent bystanders? (b) Why do terrorists seem motivated by ancient conflicts? We incorporate findings from the entitativity literature to provide insights into how perceptions of in-groups and out-groups are key processes influencing violent extremism.
The Neotoma Paleoecology Database is a community-curated data resource that supports interdisciplinary global change research by enabling broad-scale studies of taxon and community diversity, distributions, and dynamics during the large environmental changes of the past. By consolidating many kinds of data into a common repository, Neotoma lowers costs of paleodata management, makes paleoecological data openly available, and offers a high-quality, curated resource. Neotoma’s distributed scientific governance model is flexible and scalable, with many open pathways for participation by new members, data contributors, stewards, and research communities. The Neotoma data model supports, or can be extended to support, any kind of paleoecological or paleoenvironmental data from sedimentary archives. Data additions to Neotoma are growing and now include >3.8 million observations, >17,000 datasets, and >9200 sites. Dataset types currently include fossil pollen, vertebrates, diatoms, ostracodes, macroinvertebrates, plant macrofossils, insects, testate amoebae, geochronological data, and the recently added organic biomarkers, stable isotopes, and specimen-level data. Multiple avenues exist to obtain Neotoma data, including the Explorer map-based interface, an application programming interface, the neotoma R package, and digital object identifiers. As the volume and variety of scientific data grow, community-curated data resources such as Neotoma have become foundational infrastructure for big data science.
OBJECTIVES/SPECIFIC AIMS: This project has 2 overarching objectives: (1) to investigate the acceptability of the Michigan Surgical and Health Optimization Program (MSHOP) among referred patients, and to describe individual motivations behind enrollment Versus nonenrollment; and (2) to identify patient and program related factors associated with adherence and LOS and readmission rates. METHODS/STUDY POPULATION: Hypothesis—(1) MSHOP participants will report overall satisfaction with the program. Individuals that are satisfied with the program will be likely to perceive the program as effective. Subjects that declined MSHOP will be more likely to perceive their outcomes as immutable. (2) MSHOP patients will have shorter hospital stays and fewer readmission compared with patients who declined MSHOP. Methods—this study will use both qualitative and quantitative methods to investigate patient experiences and program efficacy. First, a convenience sample of patients who were referred to the MSHOP within the previous 12 months will participate in structured interviews to assess program acceptability, patient satisfaction with individual components of MSHOP, and perception of program efficacy. Interviews will also include patients who declined to enroll in MSHOP. Interviews for these subjects will include questions that assess why patients chose to decline enrollment. Second, there will be a retrospective cohort study comparing hospital outcomes among patients who enrolled in MSHOP Versus those who chose not to enroll. Analysis—interviews will be recorded and transcribed for thematic analysis to identify patterns associated with satisfaction or dissatisfaction with the MSHOP. Multivariate regression will be used to determine effect of MSHOP participation on postsurgical length-of-stay and 30-day readmission rate. Demographics and procedure type will be included as covariates. RESULTS/ANTICIPATED RESULTS: In total, 28 interviews have been transcribed, and are in the initial stages of thematic analysis. Interviews have thus far suggested that patients have been satisfied with MSHOP and would recommend the intervention to other patients. Retrospective data regarding hospital length of stay for MSHOP patients from September 2014 to December 2016 has been acquired and is being processed. The characteristics of patients that tend to participate more actively in MSHOP will be explored. We anticipate that active participation in the MSHOP will be associated with shorter hospital stays and fewer readmissions. DISCUSSION/SIGNIFICANCE OF IMPACT: This study will be one of the first to characterize patient perception of MSHOP, in particular its use of tracking step counts and breathing exercises to promote a form of prehabilitation that is easier to integrate into daily life. This project will investigate MSHOP’s effect on patient outcomes, as well as explore factors that may associate with better patient adherence and outcomes. This would help further optimize the MSHOP as an intervention.