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Two species, torpedograss and Southern watergrass, are very difficult to selectively control when they invade desirable turfgrass stands. The purpose of this study was to evaluate selective control of torpedograss and Southern watergrass in ‘Tifway’ bermudagrass turf. Greater than 86% control of torpedograss was observed 4 wk after sequential treatment (WAST) with quinclorac, trifloxysulfuron-sodium, quinclorac and trifloxysulfuron-sodium, sulfentrazone + imazethapyr and quinclorac and trifloxysulfuron-sodium, and quinclorac and trifloxysulfuron-sodium followed by (fb) glyphosate. However, by 8 WAST, control was reduced to <36% for all treatments. Greatest Southern watergrass control was achieved 4 WAST with trifloxysulfuron-sodium (83%), and thiencarbazone-methyl + foramsulfuron + halosulfuron-methyl (75%). Limited control (<30%) was observed with other treatments. By 8 WAST, Southern watergrass control was <12% for all treatments. This study suggests that short-term control/suppression of these two species is possible; however, long-term control is limited with single-year programs. These weeds will probably require multiple applications in successive years to reduce infestations. Future research should continue to screen other herbicides, combinations, and timings for control of these and other perennial grass weeds.
Patients with chronic obstructive pulmonary disease (COPD) who experience acute exacerbations usually require treatment with oral steroids or antibiotics, depending on the etiology of the exacerbation. Current management is based on clinician's assessment and judgement, which lacks diagnostic accuracy and results in overtreatment. A test to guide these decisions in primary care is in development. We developed an early decision model to evaluate the cost-effectiveness of this treatment stratification test in the primary care setting in the United Kingdom.
A combined decision tree and Markov model was developed of COPD progression and the exacerbation care pathway. Sensitivity analysis was carried out to guide technology development and inform evidence generation requirements.
The base case test strategy cost GBP 423 (USD 542) less and resulted in a health gain of 0.15 quality-adjusted life-years per patient compared with not testing. Testing reduced antibiotic prescriptions by 30 percent, potentially lowering the risk of antimicrobial resistance developing. In sensitivity analysis, the result depended on the clinical effects of treating patients according to the test result, as opposed to treating according to clinical judgement alone, for which there is limited evidence. The results were less sensitive to the accuracy of the test.
Testing may be cost-saving in primary care, but this requires robust evidence on whether test-guided treatment is effective. High quality evidence on the clinical utility of testing is required for early modeling of diagnostic tests generally.
The objective of this study was to systematically review the published literature for risk factors associated with adverse outcomes in older adults sustaining blunt chest trauma.
EMBASE and MEDLINE were searched from inception until March 2017 for prognostic factors associated with adverse outcomes in older adults sustaining blunt chest trauma using a pre-specified search strategy. References were independently screened for inclusion by two reviewers. Study quality was assessed using the Quality in Prognostic Studies tool. Where appropriate, descriptive statistics were used to evaluate study characteristics and predictors of adverse outcomes.
Thirteen cohort studies representing 79,313 patients satisfied our selection criteria. Overall, 26 prognostic factors were examined across studies and were reported for morbidity (8 studies), length of stay (7 studies), mortality (6 studies), and loss of independence (1 study). No studies examined patient quality of life or emergency department recidivism. Prognostic factors associated with morbidity and mortality included age, number of rib fractures, and injury severity score. Although age and rib fractures were found to be associated with adverse outcomes in more than 3 studies, meta-analysis was not performed due to heterogeneity amongst included studies in how these variables were measured.
While blunt chest wall trauma in older adults is relatively common, the literature on prognostic factors for adverse outcomes in this patient population remains inadequate due to a paucity of high quality studies and lack of consistent reporting standards.
Studies have demonstrated that decreases in slow-wave activity (SWA) predict decreases in depressive symptoms in those with major depressive disorder (MDD), suggesting that there may be a link between SWA and mood. The aim of the present study was to determine if the consequent change in SWA regulation following a mild homeostatic sleep challenge would predict mood disturbance.
Thirty-seven depressed and fifty-nine healthy adults spent three consecutive nights in the sleep laboratory. On the third night, bedtime was delayed by 3 h, as this procedure has been shown to provoke SWA. The Profile of Mood States questionnaire was administered on the morning following the baseline and sleep delay nights to measure mood disturbance.
Results revealed that following sleep delay, a lower delta sleep ratio, indicative of inadequate dissipation of SWA from the first to the second non-rapid eye movement period, predicted increased mood disturbance in only those with MDD.
These data demonstrate that in the first half of the night, individuals with MDD who have less SWA dissipation as a consequence of impaired SWA regulation have greater mood disturbance, and may suggest that appropriate homeostatic regulation of sleep is an important factor in the disorder.
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.
Mild behavioral impairment (MBI) describes later life acquired, sustained neuropsychiatric symptoms (NPS) in cognitively normal individuals or those with mild cognitive impairment (MCI), as an at-risk state for incident cognitive decline and dementia. We developed an operational definition of MBI and tested whether the presence of MBI was related to caregiver burden in patients with subjective cognitive decline (SCD) or MCI assessed at a memory clinic.
MBI was assessed in 282 consecutive memory clinic patients with SCD (n = 119) or MCI (n = 163) in accordance with the International Society to Advance Alzheimer's Research and Treatment – Alzheimer's Association (ISTAART–AA) research diagnostic criteria. We operationalized a definition of MBI using the Neuropsychiatric Inventory Questionnaire (NPI-Q). Caregiver burden was assessed using the Zarit caregiver burden scale. Generalized linear regression was used to model the effect of MBI domains on caregiver burden.
While MBI was more prevalent in MCI (85.3%) than in SCD (76.5%), this difference was not statistically significant (p = 0.06). Prevalence estimates across MBI domains were affective dysregulation (77.8%); impulse control (64.4%); decreased motivation (51.7%); social inappropriateness (27.8%); and abnormal perception or thought content (8.7%). Affective dysregulation (p = 0.03) and decreased motivation (p=0.01) were more prevalent in MCI than SCD patients. Caregiver burden was 3.35 times higher when MBI was present after controlling for age, education, sex, and MCI (p < 0.0001).
MBI was common in memory clinic patients without dementia and was associated with greater caregiver burden. These data show that MBI is a common and clinically relevant syndrome.
Mandatory I fortification in bread was introduced in Australia in 2009 in response to the re-emergence of biochemical I deficiency based on median urinary I concentration (UIC)<100 µg/l. Data on the I status of lactating mothers and their infants in Australia are scarce. The primary aim of this study was to assess the I status, determined by UIC and breast milk I concentration (BMIC), of breast-feeding mothers in South Australia and UIC of their infants. The secondary aim was to assess the relationship between the I status of mothers and their infants. The median UIC of the mothers (n 686) was 125 (interquartile range (IQR) 76–200) µg/l and median BMIC (n 538) was 127 (IQR 84–184) µg/l. In all, 38 and 36 % of the mothers had a UIC and BMIC below 100 µg/l, respectively. The median UIC of infants (n 628) was 198 (IQR 121–296) µg/l, and 17 % had UIC<100 µg/l. Infant UIC was positively associated with maternal UIC (β 0·26; 95 % CI 0·14, 0·37, P<0·001) and BMIC (β 0·85; 95 % CI 0·66, 1·04, P<0·001) at 3 months postpartum after adjustment for gestational age, parity, maternal secondary and further education, BMI category and infant feeding mode. The adjusted OR for infant UIC<100 µg/l was 6·49 (95 % CI 3·80, 11·08, P<0·001) in mothers with BMIC<100 µg/l compared with those with BMIC≥100 µg/l. The I status of mothers and breast-fed infants in South Australia, following mandatory I fortification, is indicative of I sufficiency. BMIC<100 µg/l increased the risk of biochemical I deficiency in breast-fed infants.
Timing of weed emergence and seed persistence in the soil influence the ability to implement timely and effective control practices. Emergence patterns and seed persistence of kochia populations were monitored in 2010 and 2011 at sites in Kansas, Colorado, Wyoming, Nebraska, and South Dakota. Weekly observations of emergence were initiated in March and continued until no new emergence occurred. Seed was harvested from each site, placed into 100-seed mesh packets, and buried at depths of 0, 2.5, and 10 cm in fall of 2010 and 2011. Packets were exhumed at 6-mo intervals over 2 yr. Viability of exhumed seeds was evaluated. Nonlinear mixed-effects Weibull models were fit to cumulative emergence (%) across growing degree days (GDD) and to viable seed (%) across burial time to describe their fixed and random effects across site-years. Final emergence densities varied among site-years and ranged from as few as 4 to almost 380,000 seedlings m−2. Across 11 site-years in Kansas, cumulative GDD needed for 10% emergence were 168, while across 6 site-years in Wyoming and Nebraska, only 90 GDD were needed; on the calendar, this date shifted from early to late March. The majority (>95%) of kochia seed did not persist for more than 2 yr. Remaining seed viability was generally >80% when seeds were exhumed within 6 mo after burial in March, and declined to <5% by October of the first year after burial. Burial did not appear to increase or decrease seed viability over time but placed seed in a position from which seedling emergence would not be possible. High seedling emergence that occurs very early in the spring emphasizes the need for fall or early spring PRE weed control such as tillage, herbicides, and cover crops, while continued emergence into midsummer emphasizes the need for extended periods of kochia management.
To determine the impact of an environmental disinfection intervention on the incidence of healthcare-associated Clostridium difficile infection (CDI).
A multicenter randomized trial.
In total,16 acute-care hospitals in northeastern Ohio participated in the study.
We conducted a 12-month randomized trial to compare standard cleaning to enhanced cleaning that included monitoring of environmental services (EVS) personnel performance with feedback to EVS and infection control staff. We assessed the thoroughness of cleaning based on fluorescent marker removal from high-touch surfaces and the effectiveness of disinfection based on environmental cultures for C. difficile. A linear mixed model was used to compare CDI rates in the intervention and postintervention periods for control and intervention hospitals. The primary outcome was the incidence of healthcare-associated CDI.
Overall, 7 intervention hospitals and 8 control hospitals completed the study. The intervention resulted in significantly increased fluorescent marker removal in CDI and non-CDI rooms and decreased recovery of C. difficile from high-touch surfaces in CDI rooms. However, no reduction was observed in the incidence of healthcare-associated CDI in the intervention hospitals during the intervention and postintervention periods. Moreover, there was no correlation between the percentage of positive cultures after cleaning of CDI or non-CDI rooms and the incidence of healthcare-associated CDI.
An environmental disinfection intervention improved the thoroughness and effectiveness of cleaning but did not reduce the incidence of healthcare-associated CDI. Thus, interventions that focus only on improving cleaning may not be sufficient to control healthcare-associated CDI.
The intricate hierarchical microstructures typical of biological materials give rise to fascinating combinations of anisotropic mechanical properties that can surpass those of man-made materials. The linking together of three-dimensional (3D) imaging techniques has the potential to reveal these structures in unprecedented detail. However, a complete understanding can only be reached if the relationship between structure and mechanical properties can be elucidated. X-ray-computed tomography (CT) is uniquely placed to image such structures across a wide range of length scales. We review recent technical advances that are leading to improved contrast and spatial resolution. We highlight how time-lapse CT 3D studies can track the response of hierarchical microstructures to mechanical loading.
The South Sandwich Islands and associated seamounts constitute the volcanic arc of an active subduction system situated in the South Atlantic. We introduce a map of the bathymetry and geological setting of the South Sandwich Islands and the associated East Scotia Ridge back-arc spreading centre that consists of two sides: side 1, a regional overview of the volcanic arc, trench and back-arc, and side 2, detailed maps of the individual islands. Side 1 displays the bathymetry at scale 1:750 000 of the intra-oceanic, largely submarine South Sandwich arc, the back-arc system and other tectonic boundaries of the subduction system. Satellite images of the islands on side 2 are at scales of 1:50 000 and 1:25 000 with contours and main volcanological features indicated. These maps are the first detailed topological and bathymetric maps of the area. The islands are entirely volcanic in origin, and most have been volcanically or fumarolically active in historic times. Many of the islands are ice-covered, and the map forms a baseline for future glaciological changes caused by volcanic activities and climate change. The back-arc spreading centre consists of nine segments, most of which have rift-like morphologies.
We propose and apply a Fourier-based symmetry-reduction scheme to remove, or quotient, the streamwise translation symmetry of laser-induced-fluorescence measurements of turbulent pipe flows that are viewed as dynamical systems in a high-dimensional state space. We also explain the relation between Taylor’s hypothesis and the comoving frame velocity
of the turbulent orbit in state space. In particular, in physical space we observe flow structures that deform as they advect downstream at a speed that differs significantly from
. Indeed, the symmetry-reduction analysis of planar dye concentration fields at Reynolds number
reveals that the speed
at which high-concentration peaks advect is roughly 1.43 times
. In a physically meaningful symmetry-reduced frame, the excess speed
can be explained in terms of the so-called geometric phase velocity
associated with the orbit in state space. The ‘self-propulsion velocity’
is induced by the shape-changing dynamics of passive scalar structures observed in the symmetry-reduced frame, in analogy with that of a swimmer at low Reynolds numbers.