Fitting multilevel models in complex survey data with design weights: Recommendations

Abstract Background Multilevel models (MLM) offer complex survey data analysts a unique approach to understanding individual and contextual determinants of public health. However, little summarized guidance exists with regard to fitting MLM in complex survey data with design weights. Simulation work suggests that analysts should scale design weights using two methods and fit the MLM using unweighted and scaled-weighted data. This article examines the performance of scaled-weighted and unweighted analyses across a variety of MLM and software programs. Methods Using data from the 2005–2006 National Survey of Children with Special Health Care Needs (NS-CSHCN: n = 40,723) that collected data from children clustered within states, I examine the performance of scaling methods across outcome type (categorical vs. continuous), model type (level-1, level-2, or combined), and software (Mplus, MLwiN, and GLLAMM). Results Scaled weighted estimates and standard errors differed slightly from unweighted analyses, agreeing more with each other than with unweighted analyses. However, observed differences were minimal and did not lead to different inferential conclusions. Likewise, results demonstrated minimal differences across software programs, increasing confidence in results and inferential conclusions independent of software choice. Conclusion If including design weights in MLM, analysts should scale the weights and use software that properly includes the scaled weights in the estimation.</p

Selenoprotein gene expression in an intestinal cell line during selenium depletion: a macroarray approach indicates effects on SelW and glutathione peroxidise 1.

The micronutrient selenium (Se) is incoprprated into a renage of selenoproteins involved in numerous biochemical processes within the body

Deductive synthesis of recursive plans in linear logic

Linear logic has previously been shown to be suitable for describing and deductively solving planning problems involving conjunction and disjunction. We introduce a recursively defined datatype and a corresponding induction rule, thereby allowing recursive plans to be synthesised. In order to make explicit the relationship between proofs and plans, we enhance the linear logic deduction rules to handle plans as a form of proof term

John C. Carapanayiotis (1909. – 1999.): grčki radiolog i pionir fizijatrije u Grčkoj

John C. Carapanayiotis was specialized in physical medicine and rehabilitation in the USA in 1948, at a time when the medical world in post-war Greece was ignorant of this specific medical specialty, and the political, economic and social backdrop was incapable of accepting and understanding the wealth of scientific knowledge that he was trying to introduce. At this point it should be noted that the specialty of Physical Medicine and Rehabilitation was established in Greece in 1973. John C. Carapanayiotis was a member of the American Congress of Physical Medicine during the 1950’s. In the same period, he expressed interest, on behalf of the New York University, in the establishment of a Physical Therapy Clinic in Greece, which would be granted unlimited funding by the Marshal Plan. His efforts clashed constantly with the backward mentality of his time, with the entrenched conservatism and with the bureaucratic red tape. Unfortunately, he was far ahead of his time and was condemned to the same fate as all other visionaries and pioneers in the way that his knowledge and scientific background were not put into practice for decades to come.John C. Carapanayiotis specijalizirao je fizikalnu medicine i rehabilitaciju 1948. u SAD-u, u vrijeme kada medicinski svijet u poslijeratnoj Grčkoj još nije bio upoznat s ovom specifičnom medicinskom specijalizacijom, a politička, ekonomska i društvena pozadina nije bila spremna prihvatiti bogatstvo znanstvenih spoznaja koje je pokušavao uvesti. Specijalizacija fizikalne medicine i rehabilitacije u Grčkoj je osnovana 1973. godine. John C. Carapanayiotis bio je član Američkog kongresa fizikalne medicine tijekom 1950-ih. U istom je razdoblju izrazio zainteresiranost, u ime Sveučilišta u New Yorku, za osnivanje Klinike za fizikalnu terapiju u Grčkoj, kojoj bi Marshallovim planom bilo odobreno neograničeno financiranje. Njegovi su se napori stalno sukobljavali s nazadnim mentalitetom njegova vremena, s ukorijenjenim konzervativizmom i birokracijom. Bio je daleko ispred svoga vremena, osuđen na sudbinu svih ostalih vizionara i pionira kojima se znanje i znanstvena pozadina nisu primjenjivali još desetljećima

Socioeconomic variation in diet and activity-related behaviours of Australian children and adolescents aged 2–16 years

BackgroundEvidence for age-related variation in the relationship between obesity-related behaviours and socioeconomic position may assist in the targeting of dietary and physical activity interventions among children.ObjectiveTo investigate the relationship between different indicators of socioeconomic position and obesity-related behaviours across childhood and adolescence.MethodsData were from 4487 children aged 2 to 16 years participating in the cross-sectional 2007 Australian National Children\u27s Nutrition and Physical Activity Survey. Socioeconomic position was defined by the highest education of the primary or secondary carer and parental income. Activity was assessed using recall methods with physical activity also assessed using pedometers. Intake of energy-dense drinks and snack foods, fruits and vegetables was assessed using 2&thinsp;&times;&thinsp;24-h dietary recalls.ResultsA socioeconomic gradient was evident for each dietary measure (although in age-specific analyses, not for energy-dense snacks in older children), as well as television viewing, but not physical activity. Whether each behaviour was most strongly related to parental income or education of the primary or secondary carer was age and sex dependent. The socioeconomic gradient was strongest for television viewing time and consumption of fruit and energy-dense drinks.ConclusionsA strong socioeconomic gradient in eating behaviours and television viewing time was observed. Relationships for particular behaviours differed by age, sex and how socioeconomic position was defined. Socioeconomic indicators define different population groups and represent different components of socioeconomic position. These findings may provide insights into who should be targeted in preventive health efforts at different life stages

Gluten-free Diet Reduces the Risk of Irritable Bowel Syndrome: A Mendelian Randomization Analysis

Background: Whether a gluten-free diet (GFD) is a cause of irritable bowel syndrome (IBS) remains controversial. We aim at exploring the causal relationship between gluten intake and IBS within Mendelian randomization (MR) design. Methods: We conducted a two-sample MR and selected single-nucleotide polymorphisms (SNPs) associated with GFD as instrumental variables (IVs). SNPs and genetic associations with GFD and IBS were obtained from the latest genome-wide association studies (GWAS) in Europeans (GFD: cases: 1,376; controls: 63,573; IBS: cases:1,121; controls: 360,073). We performed inverse variance weighting (IVW) as the primary method with several sensitivity analyses like MR-Egger and MR-PRESSO for quality control. The above analyses were re-run using another large dataset of IBS, as well as changing the p-value threshold when screening IVs, to verify the stability of the results. Results: The final estimate indicated significant causal association [per one copy of effect allele predicted log odds ratio (OR) change in GFD intake: OR = 0.97, 95% confidence interval (CI) 0.96 to 0.99, p < 0.01] without heterogeneity statistically (Q = 2.48, p = 0.78) nor horizontal pleiotropy biasing the causality (p = 0.92). Consistent results were found in validation analyses. Results of MR Steiger directionality test indicated the accuracy of our estimate of the causal direction (Steiger p < 0.001). Conclusion: GFD might be a protective factor of IBS. Therefore, we suggest taking a diet of lower gluten intake into account in IBS prevention and clinical practice

Synthetic RNA Silencing of Actinorhodin Biosynthesis in Streptomyces coelicolor A3(2)

We demonstrate the first application of synthetic RNA gene silencers in Streptomyces coelicolor A3(2). Peptide nucleic acid and expressed antisense RNA silencers successfully inhibited actinorhodin production. Synthetic RNA silencing was target-specific and is a new tool for gene regulation and metabolic engineering studies in Streptomyces.Peer reviewe