1,270 research outputs found
Leptodora kindtii Population Dynamics in the Island Region of Western Lake Erie before and after the Invasion of the Predacious Cladoceran Bythotrephes longimanus
Competition among native and non-native species can cause decreases in population size and production of both species. The native predaceous crustacean zooplankter Leptodora kindtii shares a similar niche with the invasive Bythotrephes longimanus in Lake Erie. This niche overlap may contribute to the decline in abundance and production of Leptodora in the western basin of Lake Erie. Historical (1946) and recent (2006) data were used to determine if the decline in Leptodora abundance and production was associated with the effects of Bythotrephes, which invaded Lake Erie in the mid-1980’s. Pre-invasion abundances and lengths of L. kindtii were compared with current data (2006). A change in prey community abundance, composition and dynamics were observed, relative to pre-invasion, with a marked decline in.abundance and size of L. kindtii after the invasion of Bythotrephes. Competition for food and direct predation are two explanations, among others, for the declines observed in L. kindtii size, abundance and production that have occurred since B. longimanus invasion
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Self-management support for chronic disease in primary care: frequency of patient self-management problems and patient reported priorities, and alignment with ultimate behavior goal selection.
BackgroundTo enable delivery of high quality patient-centered care, as well as to allow primary care health systems to allocate appropriate resources that align with patients' identified self-management problems (SM-Problems) and priorities (SM-Priorities), a practical, systematic method for assessing self-management needs and priorities is needed. In the current report, we present patient reported data generated from Connection to Health (CTH), to identify the frequency of patients' reported SM-Problems and SM-Priorities; and examine the degree of alignment between patient SM-Priorities and the ultimate Patient-Healthcare team member selected Behavioral Goal.MethodsCTH, an electronic self-management support system, was embedded into the flow of existing primary care visits in 25 primary care clinics and was used to assess patient-reported SM-Problems across 12 areas, patient identified SM-Priorities, and guide the selection of a Patient-Healthcare team member selected Behavioral Goal. SM-Problems included: BMI, diet (fruits and vegetables, salt, fat, sugar sweetened beverages), physical activity, missed medications, tobacco and alcohol use, health-related distress, general life stress, and depression symptoms. Descriptive analyses documented SM-Problems and SM-Priorities, and alignment between SM-Priorities and Goal Selection, followed by mixed models adjusting for clinic.Results446 participants with ≥ one chronic diseases (mean age 55.4 ± 12.6; 58.5% female) participated. On average, participants reported experiencing challenges in 7 out of the 12 SM-Problems areas; with the most frequent problems including: BMI, aspects of diet, and physical activity. Patient SM-Priorities were variable across the self-management areas. Patient- Healthcare team member Goal selection aligned well with patient SM-Priorities when patients prioritized weight loss or physical activity, but not in other self-management areas.ConclusionParticipants reported experiencing multiple SM-Problems. While patients show great variability in their SM-Priorities, the resulting action plan goals that patients create with their healthcare team member show a lack of diversity, with a disproportionate focus on weight loss and physical activity with missed opportunities for using goal setting to create targeted patient-centered plans focused in other SM-Priority areas. Aggregated results can assist with the identification of high frequency patient SM-Problems and SM-Priority areas, and in turn inform resource allocation to meet patient needs.Trial registrationClinicalTrials.gov ID: NCT01945918
First-year sea-ice contact predicts bromine monoxide (BrO) levels better than potential frost flower contact
International audienceReactive halogens are responsible for boundary-layer ozone depletion and mercury deposition in Polar Regions during springtime. To investigate the source of reactive halogens in the air arriving at Barrow, Alaska, we measured BrO, a marker of reactive halogen chemistry, and correlated its abundance with airmass histories derived from meteorological back trajectories and remotely sensed sea ice properties. The BrO is found to be positively correlated to first-year sea-ice contact (R2=0.55), and weakly negatively correlated to potential frost flower (PFF) contact (R2=0.04). These data indicate that snow contaminated with sea salts on first-year sea ice is a more probable bromine source than are frost flowers. Recent climate-driven changes in Arctic sea ice are likely to alter frost flower and first year sea ice prevalence, suggesting a significant change in reactive halogen abundance, which will alter the chemistry of the overlying Arctic atmosphere
Ill-posedness of degenerate dispersive equations
In this article we provide numerical and analytical evidence that some
degenerate dispersive partial differential equations are ill-posed.
Specifically we study the K(2,2) equation and
the "degenerate Airy" equation . For K(2,2) our results are
computational in nature: we conduct a series of numerical simulations which
demonstrate that data which is very small in can be of unit size at a
fixed time which is independent of the data's size. For the degenerate Airy
equation, our results are fully rigorous: we prove the existence of a compactly
supported self-similar solution which, when combined with certain scaling
invariances, implies ill-posedness (also in )
The Classification of Obsessive–Compulsive and Related Disorders in the ICD-11
Background To present the rationale for the new Obsessive–Compulsive and Related Disorders (OCRD) grouping in the Mental and Behavioural Disorders chapter of the Eleventh Revision of the World Health Organization’s International Classification of Diseases and Related Health Problems (ICD-11), including the conceptualization and essential features of disorders in this grouping. Methods Review of the recommendations of the ICD-11 Working Group on the Classification for OCRD. These sought to maximize clinical utility, global applicability, and scientific validity. Results The rationale for the grouping is based on common clinical features of included disorders including repetitive unwanted thoughts and associated behaviours, and is supported by emerging evidence from imaging, neurochemical, and genetic studies. The proposed grouping includes obsessive–compulsive disorder, body dysmorphic disorder, hypochondriasis, olfactory reference disorder, and hoarding disorder. Body-focused repetitive behaviour disorders, including trichotillomania and excoriation disorder are also included. Tourette disorder, a neurological disorder in ICD-11, and personality disorder with anankastic features, a personality disorder in ICD-11, are recommended for cross-referencing. Limitations Alternative nosological conceptualizations have been described in the literature and have some merit and empirical basis. Further work is needed to determine whether the proposed ICD-11 OCRD grouping and diagnostic guidelines are mostly likely to achieve the goals of maximizing clinical utility and global applicability. Conclusion It is anticipated that creation of an OCRD grouping will contribute to accurate identification and appropriate treatment of affected patients as well as research efforts aimed at improving our understanding of the prevalence, assessment, and management of its constituent disorders
Review of the quarter's economic trends [April 1980]
This brief paper surveys recent world and UK economic data and reveals that there are some signs to suggest that the world economy will withstand the 1979 oil price shock better than it did in 1973/74. The main difference is that the 1979 price rise was not super-imposed on as severe an inflation as that which occurred on the previous occasion. The present rate of increase in the world prices should not reach the levels of the last cycle when the twelve month increase in manufacturing prices peaked at 23%. Advance warning by US economists that 1979 was going to be a year of difficulty did not go unnoticed by businessmen in that country who took steps in 1978 to avoid a repetition of the inventory boom and bust cycle which had proved so costly in the recession of 1973/74. Also, consumer expectations are adjusting towards a continuing rise in the price of oil. In the UK real GDP is expected to fall by 2½% from mid-year 1980. Thereafter, it is assumed to grow at an average annual rate of 1% for the next four years
Over-expression of a putative poplar glycosyltransferase gene, PtGT1, in tobacco increases lignin content and causes early flowering
Family 1 glycosyltransferases catalyse the glycosylation of small molecules and play an important role in maintaining cell homeostasis and regulating plant growth and development. In this study, a putative glycosyltransferase gene of family 1, PtGT1, was cloned from poplar (Populus tomentosa Carr.). Sequence analysis showed that this gene encodes a protein of 481 amino acid residues with a conserved PSPG box at its C-terminal, suggesting that it is active in the glycosylation of plant secondary products. The PtGT1 gene was expressed in poplar stems and leaves, with a particularly high expression level in elongating stems. Transgenic tobacco plants ectopically over-expressing PtGT1 were obtained and phenotypes were analysed. Wiesner and Mäule staining showed that stem xylem of transgenic tobacco plants stained more strongly than controls. Measurement of the Klason lignins showed much higher lignin content in the transgenic lines than in control plants. Furthermore, the ectopic over-expression of PtGT1 in tobacco resulted in an early flowering phenotype. These findings offer a possible starting point towards better understanding of the function of poplar PtGT1, and provide a novel strategy for lignin engineering and flowering control in plants through the genetic manipulation of a poplar glycosyltransferase gene
Potential Drug Abuse Therapeutics Derived from the Hallucinogenic Natural Product Salvinorin A
Previous structure-activity relationship studies of salvinorin A have shown that modification of the acetate functionality off the C-2 position to a methoxy methyl or methoxy ethyl ether moiety leads to increased potency at KOP receptors. However, the reason for this increase remains unclear. Here we report our efforts towards the synthesis and evaluation of C-2 constrained analogs of salvinorin A. These analogs were evaluated at opioid receptors in radioligand binding experiments as well as in the GTP-γ-S functional assay. One compound, 5, was found to have affinity and potency at κ opioid (KOP) receptors comparable to salvinorin A. In further studies, 5 was found to attenuate cocaine-induced drug seeking behavior in rats comparably to salvinorin A. This finding represents the first example of a salvinorin A analog that has demonstrated anti-addictive capabilities
Evolution of the Snow Area Index of the Subarctic Snowpack in Central Alaska over a Whole Season. Consequences for the Air to Snow Transfer of Pollutants
An ALMA Survey of the SCUBA-2 Cosmology Legacy Survey UKIDSS/UDS Field: Number Counts of Submillimeter Galaxies
We report the first results of AS2UDS, an 870 μm continuum survey with the Atacama Large Millimeter/Submillimeter Array (ALMA) of a total area of ~50 arcmin2 comprising a complete sample of 716 submillimeter sources drawn from the SCUBA-2 Cosmology Legacy Survey (S2CLS) map of the UKIDSS/UDS field. The S2CLS parent sample covers a 0.96 degree2 field at σ 850 = 0.90 ± 0.05 mJy beam−1. Our deep, high-resolution ALMA observations with σ 870 ~ 0.25 mJy and a 0farcs15–0farcs30 FWHM synthesized beam, provide precise locations for 695 submillimeter galaxies (SMGs) responsible for the submillimeter emission corresponding to 606 sources in the low-resolution, single-dish map. We measure the number counts of SMGs brighter than S 870 ≥ 4 mJy, free from the effects of blending and show that the normalization of the counts falls by 28% ± 2% in comparison with the SCUBA-2 published counts, but that the shape remains unchanged. We determine that % of the brighter single-dish sources with S 850 ≥ 9 mJy consist of a blend of two or more ALMA-detectable SMGs brighter than S 870 ~ 1 mJy (corresponding to a galaxy with a total-infrared luminosity of L IR gsim 1012 L ⊙), in comparison with 28% ± 2% for the single-dish sources at S 850 ≥ 5 mJy. Using the 46 single-dish submillimeter sources that contain two or more ALMA-detected SMGs with photometric redshifts, we show that there is a significant statistical excess of pairs of SMGs with similar redshifts (<1% probability of occurring by chance), suggesting that at least 30% of these blends arise from physically associated pairs of SMGs
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