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Retrieval of cloud droplet size from visible and microwave radiometric measurements during INDOEX: Implication to aerosolsâ indirect radiative effect
The effective radius of water cloud droplets is retrieved using remotely sensed passive microwave and visible data collected by aircraft during the Indian Ocean Experiment. The purpose of this study is to assess the aerosolsâ effect on cloud microphysical and radiative properties. To study this effect, we investigate the relationships among effective radius, liquid water path and number concentration of cloud droplets. The effective radius retrieval uses imager observations of reflected sunlight at 0.64 mm and liquid water path derived frommicrowave measurements. Results of an error analysis show that retrieval error is the largest for thin clouds having small visible reflectances and small liquid water path. For this reason, only pixels with visible reflectances greater than 0.2 are used in our data analysis, so that the maximum RMS error in effective radius is limited to about 4 mm. The relation between liquid water path and effective radius is examined for four different latitudinal regions. Results show that for the same liquid water path, effective radii are significantly smaller in the north than in the south, in correspondence to the north-south gradient of aerosol concentration in this region. In situ aircraft observations reveal larger cloud droplet number concentrations in the north than in the south. The north-south gradient of these variables are consistent with the aerosolsâ effect on cloud microphysics, that is, higher aerosol concentration increases the number concentration of cloud droplets, which, in turn, reduces droplet sizes given the same liquid water path and cloud thickness. Results based on comparison between data collected from northern and southern hemispheres suggest that the increase in aerosol number concentration alters cloud droplet numbers and sizes while leaving liquid water contents approximately the same.Keywords: aerosol indirect effect, liquid water path, Indian Ocean Experiment, cloud effective radiusKeywords: aerosol indirect effect, liquid water path, Indian Ocean Experiment, cloud effective radiu
Health, education, and social care provision after diagnosis of childhood visual disability
Aim: To investigate the health, education, and social care provision for children newly diagnosed with visual disability.Method: This was a national prospective study, the British Childhood Visual Impairment and Blindness Study 2 (BCVIS2), ascertaining new diagnoses of visual impairment or severe visual impairment and blindness (SVIBL), or equivalent vi-sion. Data collection was performed by managing clinicians up to 1-year follow-up, and included health and developmental needs, and health, education, and social care provision.Results: BCVIS2 identified 784 children newly diagnosed with visual impairment/SVIBL (313 with visual impairment, 471 with SVIBL). Most children had associated systemic disorders (559 [71%], 167 [54%] with visual impairment, and 392 [84%] with SVIBL). Care from multidisciplinary teams was provided for 549 children (70%). Two-thirds (515) had not received an Education, Health, and Care Plan (EHCP). Fewer children with visual impairment had seen a specialist teacher (SVIBL 35%, visual impairment 28%, Ï2p < 0.001), or had an EHCP (11% vs 7%, Ï2p < 0 . 01).Interpretation: Families need additional support from managing clinicians to access recommended complex interventions such as the use of multidisciplinary teams and educational support. This need is pressing, as the population of children with visual impairment/SVIBL is expected to grow in size and complexity.This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited
Patients\u27 Anxiety and Expectations: How They Influence Family Physicians\u27 Decisions to Order Cancer Screening Tests
OBJECTIVE: To compare the infl uence of physicians\u27 recommendations and patients\u27 anxiety or expectations on the decision to order four cancer screening tests in clinical situations where guidelines were equivocal: screening for prostate cancer with prostate-specific antigen for men older than 50; breast cancer screening with mammography for women 40 to 49; colorectal cancer screening with fecal occult blood testing; and colorectal cancer screening with colonoscopy for patients older than 40. DESIGN: Cross-sectional mailed survey with clinical vignettes. SETTING: British Columbia, Alberta, Ontario, Quebec, and Prince Edward Island. PARTICIPANTS: Of 600 randomly selected family physicians in active practice approached, 351 responded, but 35 respondents were ineligible (response rate 62%). MAIN OUTCOME MEASURES: Decisions to order cancer screening tests, physicians\u27 perceptions of recommendations, patients\u27 anxiety about cancer, and patients\u27 expectation to be tested. RESULTS: For all screening situations, physicians most likely to order the tests believed that routine screening with the test was recommended; physicians least likely to order tests believed routine screening was not. Patients\u27 expectations or anxiety, however, markedly increased screening by physicians who did not believe that routine screening was recommended. In regression models, the interaction between physicians\u27 recommendations and patients\u27 anxiety or expectation was significant for all four screening tests. When patients had no anxiety or expectations, physicians\u27 beliefs about screening strongly predicted test ordering. Physicians who believed routine screening was recommended ordered the test in most cases regardless of patient characteristics. But patients\u27 anxiety or expectations markedly increased the probability that the test would be ordered. The probability of test ordering went from 0.28 to 0.54 for prostate-specific antigen (odds ratio [OR] = 1.9), from 0.15 to 0.44 for mammography (OR = 2.8), from 0.33 to 0.79 for fecal occult blood testing (OR = 2.4), and from 0.29 to 0.65 for colonoscopy (OR = 2.2). CONCLUSION: Differences in clinical judgment about recommended practice lead to practice variation, but physicians are also influenced by nonmedical factors, such as patients\u27 anxiety and expectations of receiving tests. In terms of magnitude of influence, clinical judgment is more powerful than nonmedical patient factors, but patient factors are also powerful drivers of family physicians\u27 decisions about cancer screening when practice guidelines are equivocal
PROJECTING THE BIOLOGICAL CONDITION OF STREAMS UNDER ALTERNATIVE SCENARIOS OF HUMAN LAND USE
Dnmt1 has de novo activity targeted to transposable elements
DNA methylation plays a critical role during development, particularly in repressing retrotransposons. The mammalian methylation landscape is dependent on the combined activities of the canonical maintenance enzyme Dnmt1 and the de novo Dnmts, 3a and 3b. Here, we demonstrate that Dnmt1 displays de novo methylation activity in vitro and in vivo with specific retrotransposon targeting. We used whole-genome bisulfite and long-read Nanopore sequencing in genetically engineered methylation-depleted mouse embryonic stem cells to provide an in-depth assessment and quantification of this activity. Utilizing additional knockout lines and molecular characterization, we show that the de novo methylation activity of Dnmt1 depends on Uhrf1, and its genomic recruitment overlaps with regions that enrich for Uhrf1, Trim28 and H3K9 trimethylation. Our data demonstrate that Dnmt1 can catalyze DNA methylation in both a de novo and maintenance context, especially at retrotransposons, where this mechanism may provide additional stability for long-term repression and epigenetic propagation throughout development
Making Sense of Resilience: A Useful Step on the Road to Creating and Maintaining Resilient Students and School Communities
What Influences Family Physicians\u27 Cancer Screening Decisions When Practice Guidelines Are Unclear or Conflicting?
OBJECTIVES: To determine (a) the respondents\u27 perceptions of 4 unclear or conflicting cancer screening guidelines: prostate-specific antigen (PSA) for men over 50, mammography for women 40-49, colorectal screening by fecal occult blood testing (FOBT), and colonoscopy for patients over 40; and (b) the influence of various factors on the decision to order these tests. STUDY DESIGN: National Canadian mail survey of randomly selected family physicians. POPULATION: Family physicians in active practice (n=565) selected from rural and urban family medicine sites in 5 provinces representing the main regions in Canada. OUTCOME MEASURED: Agreement with guideline statements, and decision to order screening test in 6 clinical vignettes. RESULTS: Of 565 surveys mailed, 351 (62.1%) were returned. Most respondents agreed with the Canadian Task Force recommendations, and most believed that various guidelines for 3 of the 4 screens were conflicting (PSA 86.6%; mammography 67.5%; FOBT 62.4%). Patient anxiety about cancer, patient expectations of being tested, and a positive family history of cancer increased the odds that the 4 tests would be ordered. A good quality patient-MD relationship decreased the odds of ordering a mammogram. Screening decisions were also significantly influenced by the respondents\u27 beliefs about whether screening was recommended and whether screening could cause more harm than good. A physician\u27s sensitivity to his or her colleagues\u27 practice influenced screening decisions regarding PSA and mammography. CONCLUSIONS: These results suggest a conceptual framework for understanding the determinants of screening behavior when guidelines are unclear or conflicting