Topological Effect on Molecular Orbitals. Part 8. A Study of Two Further Classes of Topologically Related Isomers.

The family of isomers which exhibit the Topological Effect on Molecular Orbitals (TEMO) is enlarged by two further classes. The conditions which the central fragment C (used in the construction of isomers) must satisfy so that a minimum of inversions occurs are analyzed. The inversions in TEMO and the predictions on the HOMO-LUMO separation of topologically related isomers are discussed for different central fragments. The findings are supported by simple MO-calculations and by a series of experimental data

Implementation issues in chemistry and transport models

International audienceOffline chemistry and transport models (CTMs) are versatile tools for studying composition and climate issues requiring multi-decadal simulations. They are computationally fast compared to coupled chemistry climate models, making them well-suited for integrating sensitivity experiments necessary for understanding model performance and interpreting results. The archived meteorological fields used by CTMs can be implemented with lower horizontal or vertical resolution than the original meteorological fields in order to shorten integration time, but the effects of these shortcuts on transport processes must be understood if the CTM is to have credibility. In this paper we present a series of CTM experiments, each differing from another by a single feature of the implementation. Transport effects arising from changes in resolution and model lid height are evaluated using process-oriented diagnostics that intercompare CH4, O3, and age tracer carried in the simulations. Some of the diagnostics used are derived from observations and are shown as a reality check for the model. Processes evaluated include the tropical ascent, tropical-midlatitude exchange, the poleward circulation in the upper stratosphere, and the development of the Antarctic vortex. We find that faithful representation of stratospheric transport in this CTM using Lin and Rood advection is possible with a full mesosphere, ~1 km resolution in the lower stratosphere, and relatively low vertical resolution (>4 km spacing) in the middle stratosphere and above, but lowering the lid from the upper to lower mesosphere leads to less realistic constituent distributions in the upper stratosphere. Ultimately, this affects the polar lower stratosphere, but the effects are greater for the Antarctic than the Arctic. The fidelity of lower stratospheric transport requires realistic tropical and high latitude mixing barriers which are produced at 2°×2.5°, but not lower resolution. At 2°×2.5° resolution, the CTM produces a vortex capable of isolating perturbed chemistry (e.g. high Cly and low NOy) required for simulating polar ozone loss

Caregivers of Children with Disabilities: An Exploratory Study of Factors Influencing Occupational Therapy Home Programming Engagement

Purpose: Home programming for children with disabilities is prescribed frequently by occupational therapists as an effective adjunct to practice-setting occupational therapy. The effectiveness of home programming is largely influenced by the degree to which caregivers (and children) adhere to the home programming parameters. Numerous factors are thought to promote or limit home programming adherence but there is a lack of quantitative research addressing the relationships between these factors and home programming adherence. The purpose of this quantitative, independent study was to explore the factors that are correlated with or influence caregivers’ adherence to their child’s occupational therapy home program. A secondary purpose of this study was to analyze the reliability of the Multi-dimensional Occupational Therapy Home Programming Engagement Survey. Methods: A prospective, exploratory online survey design was used to gather data to answer the research questions. Following IRB approval, convenience sampling was used to access respondents and gather data. Fifteen caregivers of children with disabilities completed a 44 question online survey. The Multi-dimensional Occupational Therapy Home Programming Engagement Survey was created by the researchers and was guided by the concepts within the Model of Human Occupation. Statistical analysis was used to analyze descriptive statistics, Pearson’s correlations, Spearman rho’s, tests of internal consistency, and ANOVAs to answer the research questions. Results: The results indicated significant relationships between caregiver home programming adherence and the perceived benefits to the child, caregiver value for the home program, activities fitting within the families’ daily routine, the frequency that the home program is recommended throughout the week, and the age of the child receiving occupational therapy home programming. Each of these factors contributed to greater caregiver adherence with implementing the child’s home program. No statistical significance was reached for adherence related to the environment, child and caregiver performance capacity, demographics, and the child’s ability to complete daily tasks within his or her home and school, as well as to socially interact. These factors were not related to home programming adherence. Conclusion: Numerous factors influence caregiver and children’s occupational therapy home programming adherence. In order to increase overall adherence rates to home programming, it is essential that occupational therapists consider and engage in discussion about these factors (i.e. caregiver value, benefits to child, daily routines, etc.) with caregivers when prescribing pediatric home programs. Finally, further quantitative research studies are needed to more fully understand the variables influencing familial home programming engagement and methods that occupational therapists may use to enhance home programming adherence

On Some Further Classes of Isomers Which Exhibit Topological Effect on Molecular Orbitals

Some further classes of isomers exibiting the Topological Effect on Molecular Orbitals (TEMO) are considered. They include two classes of hetero-substituted polyenes and three classes of substituted annulenes. The sixth class contains bridged annulenes where TEMO is exhibited only for the related matching spectra

Acyclic and Characteristic Polynomial of Regular Conjugated Polymers and Their Derivatives

A method to study the acyclic and characteristic polynomial of regular conjugated polymers is described. For a regular polymer with l bonds linking the monomer units, one first builds a 2\u27X21 polynomial matrix T1. Its matrix elements are acyclic polynomials of the monomer unit graph and its subgraphs obtained by successive deletion of atoms serving as the linking sites. The acyclic polynomials of the fasciagraph (representing an open polymeric chain) and some of its subgraphs are then obtained as the appropriate matrix elements of Ti" where M stands for the degree of polymerization of the polymer under consideration. For the rotagraph (representing the polymeric chain closed on itself) the acyclic polynomial equal the trace of T1". It is proved that the acyclic polynomials of regular polymers and some of their derivatives satisfy recursion formulae of the same form which contain 21 + 1 terms. The coefficients appearing in the recursion are derived only from the knowledge of the matrix Ti and are, therefore, independent of M. As far as the characteristic polynomial of a regular polymer is concerned, here we apply an analogon of the Ti-formalism only for the special case of l = 1 and reproduce an already known recursion formula. However, a new determinantal representation of the characteristic polynomial of a polymer as well as its explicit expression in terms of the characteristic polynomials of monomer graph and its subgraphs is established for this special case

Acyclic and Characteristic Polynomial of Regular Conjugated Polymers and Their Derivatives

A method to study the acyclic and characteristic polynomial of regular conjugated polymers is described. For a regular polymer with l bonds linking the monomer units, one first builds a 2\u27X21 polynomial matrix T1. Its matrix elements are acyclic polynomials of the monomer unit graph and its subgraphs obtained by successive deletion of atoms serving as the linking sites. The acyclic polynomials of the fasciagraph (representing an open polymeric chain) and some of its subgraphs are then obtained as the appropriate matrix elements of Ti" where M stands for the degree of polymerization of the polymer under consideration. For the rotagraph (representing the polymeric chain closed on itself) the acyclic polynomial equal the trace of T1". It is proved that the acyclic polynomials of regular polymers and some of their derivatives satisfy recursion formulae of the same form which contain 21 + 1 terms. The coefficients appearing in the recursion are derived only from the knowledge of the matrix Ti and are, therefore, independent of M. As far as the characteristic polynomial of a regular polymer is concerned, here we apply an analogon of the Ti-formalism only for the special case of l = 1 and reproduce an already known recursion formula. However, a new determinantal representation of the characteristic polynomial of a polymer as well as its explicit expression in terms of the characteristic polynomials of monomer graph and its subgraphs is established for this special case

The Sensitivity of Arctic Ozone Loss to Polar Stratospheric Cloud Volume and Chlorine and Bromine Loading in a Chemistry and Transport Model

The sensitivity of Arctic ozone loss to polar stratospheric cloud volume (V(sub PSC)) and chlorine and bromine loading is explored using chemistry and transport models (CTMs). A simulation using multi-decadal output from a general circulation model (GCM) in the Goddard Space Flight Center (GSFC) CTM complements one recycling a single year s GCM output in the Global Modeling Initiative (GMI) CTM. Winter polar ozone loss in the GSFC CTM depends on equivalent effective stratospheric chlorine (EESC) and polar vortex characteristics (temperatures, descent, isolation, polar stratospheric cloud amount). Polar ozone loss in the GMI CTM depends only on changes in EESC as the dynamics repeat annually. The GSFC CTM simulation reproduces a linear relationship between ozone loss and Vpsc derived from observations for 1992 - 2003 which holds for EESC within approx.85% of its maximum (approx.1990 - 2020). The GMI simulation shows that ozone loss varies linearly with EESC for constant, high V(sub PSC)

Expression and DNA methylation of TNF, IFNG and FOXP3 in colorectal cancer and their prognostic significance.

BACKGROUND: Colorectal cancer (CRC) progression is associated with suppression of host cell-mediated immunity and local immune escape mechanisms. Our aim was to assess the immune function in terms of expression of TNF, IFNG and FOXP3 in CRC. METHODS: Sixty patients with CRC and 15 matched controls were recruited. TaqMan quantitative PCR and methylation-specific PCR was performed for expression and DNA methylation analysis of TNF, IFNG and FOXP3. Survival analysis was performed over a median follow-up of 48 months. RESULTS: TNF was suppressed in tumour and IFNG was suppressed in peripheral blood mononuclear cells (PBMCs) of patients with CRC. Tumours showed enhanced expression of FOXP3 and was significantly higher when tumour size was >38 mm (median tumour size; P=0.006, Mann-Whitney U-test). Peripheral blood mononuclear cell IFNG was suppressed in recurrent CRC (P=0.01). Methylated TNFpromoter (P=0.003) and TNFexon1 (P=0.001) were associated with significant suppression of TNF in tumours. Methylated FOXP3cpg was associated with significant suppression of FOXP3 in both PBMC (P=0.018) and tumours (P=0.010). Reduced PBMC FOXP3 expression was associated with significantly worse overall survival (HR=8.319, P=0.019). CONCLUSIONS: We have detected changes in the expression of immunomodulatory genes that could act as biomarkers for prognosis and future immunotherapeutic strategies

The costs of respiratory illnesses arising from Florida gulf coast Karenia brevis blooms

This is the final version of the article. Available from NIEHS via the DOI in this recordBACKGROUND: Algal blooms of Karenia brevis, a harmful marine algae, occur almost annually off the west coast of Florida. At high concentrations, K. brevis blooms can cause harm through the release of potent toxins, known as brevetoxins, to the atmosphere. Epidemiologic studies suggest that aerosolized brevetoxins are linked to respiratory illnesses in humans. OBJECTIVES: We hypothesized a relationship between K. brevis blooms and respiratory illness visits to hospital emergency departments (EDs) while controlling for environmental factors, disease, and tourism. We sought to use this relationship to estimate the costs of illness associated with aerosolized brevetoxins. METHODS: We developed a statistical exposure-response model to express hypotheses about the relationship between respiratory illnesses and bloom events. We estimated the model with data on ED visits, K. brevis cell densities, and measures of pollen, pollutants, respiratory disease, and intra-annual population changes. RESULTS: We found that lagged K. brevis cell counts, low air temperatures, influenza outbreaks, high pollen counts, and tourist visits helped explain the number of respiratory-specific ED diagnoses. The capitalized estimated marginal costs of illness for ED respiratory illnesses associated with K. brevis blooms in Sarasota County, Florida, alone ranged from $0.5 to$4 million, depending on bloom severity. CONCLUSIONS: Blooms of K. brevis lead to significant economic impacts. The costs of illness of ED visits are a conservative estimate of the total economic impacts. It will become increasingly necessary to understand the scale of the economic losses associated with K. brevis blooms to make rational choices about appropriate mitigation.This research was sponsored by the Florida Fish & Wildlife Conservation Commission (07182) and the Departments of Environmental Protection and Health; the U.S. Centers for Disease Control and Prevention; the Center for Oceans and Human Health at the Woods Hole Oceanographic Institution [National Science Foundation (NSF) OCE-0430724; National Institute of Environmental Health Sciences (NIEHS) P50 ES012742]; the Ocean and Human Health Center at the University of Miami Rosenstiel School (NSF 0CE0432368; NIEHS 1 P50 ES12736); and the NIEHS (PO1 ES 10594)