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The morphology and growth habits of Evactinopora species of the Evactinoporidae (new family) are documented. This distinctive family of free-living bryozoans has a radial colony form at all growth stages. During a brief attachment phase on a hard substrate, the colony morphology grew as an expanding cone with vertical folds. Following detachment of the nascent colony from this hard substrate, it settled on soft sediment and the free-living expanding colony acquired a star-like form by producing slender outrigger rays. Continued growth produced a radial array of vertical vanes containing feeding autozooecia. The colony maintained a vertical orientation on soft sediment by means of outrigger rays and secretion of solid skeleton on the colony base that provided ballast. The radial growth pattern, outrigger rays, and vertical vanes developed as adaptive characters suitable for free-living life on soft sediment. North American species of Evactinopora are redefined and described taxonomically on the basis of zoarial and zooecial characters and a new species, Evactinopora mangeri, erected. The new family Evactinoporidae is established on the basis of the novel characters of early colony detachment from a hard surface, radial growth pattern through life, generation of outrigger rays, and growth of vertical vanes from the top of rays.
The use of three-dimensional printing has been rapidly expanding over the last several decades. Virtual surgical three-dimensional simulation and planning has been shown to increase efficiency and accuracy in various clinical scenarios.
To report the feasibility of three-dimensional printing in paediatric laryngotracheal stenosis and discuss potential applications of three-dimensional printed models in airway surgery.
Retrospective case series in a tertiary care aerodigestive centre.
Three-dimensional printing was undertaken in two cases of paediatric laryngotracheal stenosis. One patient with grade 4 subglottic stenosis with posterior glottic involvement underwent an extended partial cricotracheal reconstruction. Another patient with grade 4 tracheal stenosis underwent tracheal resection and end-to-end anastomosis. Models of both tracheas were printed using PolyJet technology from a Stratasys Connex2 printer.
It is feasible to demonstrate stenosis in three-dimensional printed models, allowing for patient-specific pre-operative surgical simulation. The models serve as an educational tool for patients’ understanding of the surgery, and for teaching residents and fellows.
Emotion dysregulation is a risk factor for the development of a variety of psychopathologic outcomes. In children, irritability, or dysregulated negative affect, has been the primary focus, as it predicts later negative outcomes even in very young children. However, dysregulation of positive emotion is increasingly recognized as a contributor to psychopathology. Here we used an exploratory factor analysis and defined four factors of emotion dysregulation: irritability, excitability, sadness, and anhedonia, in the preschool-age psychiatric assessment collected in a sample of 302 children ages 3–5 years enriched for early onset depression. The irritability and excitability factor scores defined in preschoolers predicted later diagnosis of mood and externalizing disorders when controlling for other factor scores, social adversity, maternal history of mood disorders, and externalizing diagnoses at baseline. The preschool excitability factor score predicted emotion lability in late childhood and early adolescence when controlling for other factor scores, social adversity, and maternal history. Both excitability and irritability factor scores in preschoolers predicted global functioning into the teen years and early adolescence, respectively. These findings underscore the importance of positive, as well as negative, affect dysregulation as early as the preschool years in predicting later psychopathology, which deserves both further study and clinical consideration.
We present a workflow to track icebergs in proglacial fjords using oblique time-lapse photos and the Lucas-Kanade optical flow algorithm. We employ the workflow at LeConte Bay, Alaska, where we ran five time-lapse cameras between April 2016 and September 2017, capturing more than 400 000 photos at frame rates of 0.5–4.0 min−1. Hourly to daily average velocity fields in map coordinates illustrate dynamic currents in the bay, with dominant downfjord velocities (exceeding 0.5 m s−1 intermittently) and several eddies. Comparisons with simultaneous Acoustic Doppler Current Profiler (ADCP) measurements yield best agreement for the uppermost ADCP levels (~ 12 m and above), in line with prevalent small icebergs that trace near-surface currents. Tracking results from multiple cameras compare favorably, although cameras with lower frame rates (0.5 min−1) tend to underestimate high flow speeds. Tests to determine requisite temporal and spatial image resolution confirm the importance of high image frame rates, while spatial resolution is of secondary importance. Application of our procedure to other fjords will be successful if iceberg concentrations are high enough and if the camera frame rates are sufficiently rapid (at least 1 min−1 for conditions similar to LeConte Bay).
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.
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.
We performed a return-on-investment analysis comparing the investment in surgical site infection (SSI) prevention programs in a hospital setting to the savings from averted SSI cases.
A retrospective case costing study using aggregated patient data to determine the incidence and costs of SSI infection in surgical departments over time. We calculated return on investment to the hospital and conducted several sensitivity and scenario analyses.
Data were compiled for the Ottawa Hospital (TOH), a Canadian tertiary-care teaching institution.
We used aggregated records for all hospital patients who underwent surgical procedures between April 2010 and January 2015.
We estimated the potential cost savings of the hospital’s surgical quality improvement program, namely the Surgeons National Surgical Quality Improvement Program (NSQIP) and the Comprehensive Unit-based Safety Program (CUSP).
From 2010 to 2016, TOH invested C$826,882 (US$624,384) in surgical quality improvement programs targeting SSI incidence and accrued C$1,885,110 (US$1,423,460) in cumulative savings from averted SSI cases, generating a return of $2.28 (US$3.02) per dollar invested (95% confidence interval [CI], −0.67 to 7.37). The study findings are sensitive to the estimated cost to the hospital per SSI case and the rate reduction attributable to the prevention program.
The NSQIP and CUSP have produced a positive return on investment at TOH; however, the result rests on several assumptions. This positive return on investment is expected to continue if the hospital can continue to reduce SSI incidence at least 0.25% annually without new investments. Findings from this study highlight the need for continuous program evaluation of the quality improvement initiatives.
High unemployment is a hallmark of psychotic illness. Individual placement and support (IPS) may be effective at assisting the vocational recoveries of young people with first-episode psychosis (FEP).
To examine the effectiveness of IPS at assisting young people with FEP to gain employment (Australian and Clinical Trials Registry ACTRN12608000094370).
Young people with FEP (n = 146) who were interested in vocational recovery were randomised using computer-generated random permuted blocks on a 1:1 ratio to: (a) 6 months of IPS in addition to treatment as usual (TAU) or (b) TAU alone. Assessments were conducted at baseline, 6 months (end of intervention), 12 months and 18 months post-baseline by research assistants who were masked to the treatment allocations.
At the end of the intervention the IPS group had a significantly higher rate of having been employed (71.2%) than the TAU group (48.0%), odds ratio 3.40 (95% CI 1.17–9.91, z = 2.25, P = 0.025). However, this difference was not seen at 12- and 18-month follow-up points. There was no difference at any time point on educational outcomes.
This is the largest trial to our knowledge on the effectiveness of IPS in FEP. The IPS group achieved a very high employment rate during the 6 months of the intervention. However, the advantage of IPS was not maintained in the long term. This seems to be related more to an unusually high rate of employment being achieved in the control group rather than a gross reduction in employment among the IPS group.
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.
To determine which healthcare worker (HCW) roles and patient care activities are associated with acquisition of vancomycin-resistant Enterococcus (VRE) on HCW gloves or gowns after patient care, as a surrogate for transmission to other patients.
Prospective cohort study.
Medical and surgical intensive care units at a tertiary-care academic institution.
VRE-colonized patients on Contact Precautions and their HCWs.
Overall, 94 VRE-colonized patients and 469 HCW–patient interactions were observed. Research staff recorded patient care activities and cultured HCW gloves and gowns for VRE before doffing and exiting patient room.
VRE were isolated from 71 of 469 HCWs’ gloves or gowns (15%) following patient care. Occupational/physical therapists, patient care technicians, nurses, and physicians were more likely than environmental services workers and other HCWs to have contaminated gloves or gowns. Compared to touching the environment alone, the odds ratio (OR) for VRE contamination associated with touching both the patient (or objects in the immediate vicinity of the patient) and environment was 2.78 (95% confidence interval [CI], 0.99–0.77) and the OR associated with touching only the patient (or objects in the immediate vicinity) was 3.65 (95% CI, 1.17–11.41). Independent risk factors for transmission of VRE to HCWs were touching the patient’s skin (OR, 2.18; 95% CI, 1.15–4.13) and transferring the patient into or out of bed (OR, 2.66; 95% CI, 1.15–6.43).
Patient contact is a major risk factor for HCW contamination and subsequent transmission. Interventions should prioritize contact precautions and hand hygiene for HCWs whose activities involve touching the patient.
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.
Objectives: Rates of cognitive, academic and behavioral comorbidities are elevated in children with epilepsy. The contribution of environmental and genetic influences to comorbidity risk is not fully understood. This study investigated children with epilepsy, their unaffected siblings, and controls to determine the presence and extent of risk associated with family relatedness across a range of epilepsy comorbidities. Methods: Participants were 346 children (8–18 years), n=180 with recent-onset epilepsy, their unaffected siblings (n=67), and healthy first-degree cousin controls (n=99). Assessments included: (1) Child Behavior Checklist/6-18 (CBCL), (2) Behavior Rating Inventory of Executive Function (BRIEF), (3) history of education and academic services, and (4) lifetime attention deficit hyperactivity disorder (ADHD) diagnosis. Analyses consisted of linear mixed effect models for continuous variables, and logistic mixed models for binary variables. Results: Differences were detected between the three groups of children across all measures (p<.001). For ADHD, academic problems, and executive dysfunction, children with epilepsy exhibited significantly more problems than unaffected siblings and controls; siblings and controls did not differ statistically significantly from each other. For social competence, children with epilepsy and their unaffected siblings displayed more abnormality compared with controls, with no statistically significant difference between children with epilepsy and unaffected siblings. For behavioral problems, children with epilepsy had more abnormality than siblings and controls, but unaffected siblings also exhibited more abnormalities than controls. Conclusions: The contribution of epilepsy and family relatedness varies across specific neurobehavioral comorbidities. Family relatedness was not significantly associated with rates of ADHD, academic problems and executive dysfunction, but was associated with competence and behavioral problems. (JINS, 2018, 24, 1–9)
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 analyze whether electronically available comorbid conditions are risk factors for Centers for Disease Control and Prevention (CDC)-defined, hospital-onset Clostridium difficile infection (CDI) after controlling for antibiotic and gastric acid suppression therapy use.
Patients aged ≥18 years admitted to the University of Maryland Medical Center between November 7, 2015, and May 31, 2017.
Comorbid conditions were assessed using the Elixhauser comorbidity index. The Elixhauser comorbidity index and the comorbid condition components were calculated using the International Classification of Disease, Tenth Revision, Clinical Modification (ICD-10-CM) codes extracted from electronic medical records. Bivariate associations between CDI and potential covariates for multivariable regression, including antibiotic use, gastric acid suppression therapy use, as well as comorbid conditions, were estimated using log binomial multivariable regression.
After controlling for antibiotic use, age, proton-pump inhibitor use, and histamine-blocker use, the Elixhauser comorbidity index was a significant risk factor for predicting CDI. There was an increased risk of 1.26 (95% CI, 1.19–1.32) of having CDI for each additional Elixhauser point added to the total Elixhauser score.
An increase in Elixhauser score is associated with CDI. Our study and other studies have shown that comorbid conditions are important risk factors for CDI. Electronically available comorbid conditions and scores like the Elixhauser index should be considered for risk-adjustment of CDC CDI rates.