The contributions of solar ultraviolet radiation exposure and other determinants to Serum 25-Hydroxyvitamin D concentrations in Australian adults : the AusD study

The Quantitative Assessment of Solar UV [ultraviolet] Exposure for Vitamin D Synthesis in Australian Adults (AusD) Study aimed to better define the relationship between sun exposure and serum 25-hydroxyvitamin D (25(OH)D) concentration. Cross-sectional data were collected between May 2009 and December 2010 from 1,002 participants aged 18-75 years in 4 Australian sites spanning 24° of latitude. Participants completed the following: 1) questionnaires on sun exposure, dietary vitamin D intake, and vitamin D supplementation; 2) 10 days of personal ultraviolet radiation dosimetry; 3) a sun exposure and physical activity diary; and 4) clinical measurements and blood collection for 25(OH)D determination. Our multiple regression model described 40% of the variance in 25(OH)D concentration; modifiable behavioral factors contributed 52% of the explained variance, and environmental and demographic or constitutional variables contributed 38% and 10%, respectively. The amount of skin exposed was the single strongest contributor to the explained variance (27%), followed by location (20%), season (17%), personal ultraviolet radiation exposure (8%), vitamin D supplementation (7%), body mass index (weight (kg)/height (m)2) (4%), and physical activity (4%). Modifiable behavioral factors strongly influence serum 25(OH)D concentrations in Australian adults. In addition, latitude was a strong determinant of the relative contribution of different behavioral factors.

A concise approach to the polycyclic scaffold of frondosin D

Frondosins A−E, 1−5 (Figure 1), are a family of related marine sesquiterpenoids first isolated in their dextro-rotatory form from the sponge Dysidea frondosa.(1a) Additionally, levo-rotatory frondosins A and D were isolated from an unidentified Eurospongia species.(1b) Frondosins A−E are compounds of interest due to their promising interleukin-8 (IL-8) affinity and protein kinase C inhibition.(1a) IL-8 antagonists are of particular interest in view of their antiinflammatory,(2a) anti-HIV,(1b, 2b) and antitumor(2c-2f) properties. To date, frondosins A, B, and C have been synthesized.(3) Notwithstanding these successes, the frondosins have proved quite a formidable synthetic challenge, and as of yet, there has been no synthesis of frondosin D or E. In this report, we describe our approaches to the molecular scaffold of frondosins D. This work has culminated in a very effective means of producing the trimethylbicyclo[5.4.0]undecane ring system common to all frondosins (shown in bold, Figure 1).

A detailed investigation of nominally 2-D radical-farming scramjet combustion

This paper reports on an investigation of the flow/chemistry coupling inside a nominally two-dimensional inlet-fuelled scramjet configuration. The experiments were conducted at a freestream Mach number of 7.3 and a total flow enthalpy of 4.3MJ/kg corresponding to a Mach 9.7 flight condition. The phenomenon of radical-farming has been studied in detail using two-dimensional OH* chemiluminescence imaging and emission spectroscopy. High signal levels of excited OH (OH*) were detected behind the first shock reflections inside the combustion chamber upstream of any measurable pressure rise from combustion, which occurred towards the rear of the combustor. The production of OH in the first hot pocket initiates the ignition process and then accelerates the combustion process in the next downstream hot pocket. This was confirmed by numerical simulations of premixed hydrogen/air flow through the scramjet. Chemical kinetics analyses reveal that the ignition process is governed by the interaction between various reaction groups leading to a chainbranching explosion for low mean temperature and pressure combustion flowfields.

High-level expression of Rhodotorula gracilis d-amino acid oxidase in Pichia pastoris

By combining gene design and heterologous over-expression of Rhodotorula gracilis D-amino acid oxidase (RgDAO) in Pichia pastoris, enzyme production was enhanced by one order of magnitude compared to literature benchmarks, giving 350 kUnits/l of fed-batch bioreactor culture with a productivity of 3.1 kUnits/l h. P. pastoris cells permeabilized by freeze-drying and incubation in 2-propanol (10% v/v) produce a highly active (1.6 kUnits/g dry matter) and stable oxidase preparation. Critical bottlenecks in the development of an RgDAO catalyst for industrial applications have been eliminated.

Stepwise engineering of a Pichia pastoris D-amino acid oxidase whole cell catalyst

Trigonopsis variabilis D-amino acid oxidase (TvDAO) is a well characterized enzyme used for cephalosporin C conversion on industrial scale. However, the demands on the enzyme with respect to activity, operational stability and costs also vary with the field of application. Processes that use the soluble enzyme suffer from fast inactivation of TvDAO while immobilized oxidase preparations raise issues related to expensive carriers and catalyst efficiency. Therefore, oxidase preparations that are more robust and active than those currently available would enable a much broader range of economically viable applications of this enzyme in fine chemical syntheses. A multi-step engineering approach was chosen here to develop a robust and highly active Pichia pastoris TvDAO whole-cell biocatalyst. As compared to the native T. variabilis host, a more than seven-fold enhancement of the intracellular level of oxidase activity was achieved in P. pastoris through expression optimization by codon redesign as well as efficient subcellular targeting of the enzyme to peroxisomes. Multi copy integration further doubled expression and the specific activity of the whole cell catalyst. From a multicopy production strain, about 1.3 x 103 U/g wet cell weight (wcw) were derived by standard induction conditions feeding pure methanol. A fed-batch cultivation protocol using a mixture of methanol and glycerol in the induction phase attenuated the apparent toxicity of the recombinant oxidase to yield final biomass concentrations in the bioreactor of >or= 200 g/L compared to only 117 g/L using the standard methanol feed. Permeabilization of P. pastoris using 10% isopropanol yielded a whole-cell enzyme preparation that showed 49% of the total available intracellular oxidase activity and was notably stabilized (by three times compared to a widely used TvDAO expressing Escherichia coli strain) under conditions of D-methionine conversion using vigorous aeration. Stepwise optimization using a multi-level engineering approach has delivered a new P. pastoris whole cell TvDAO biocatalyst showing substantially enhanced specific activity and stability under operational conditions as compared to previously reported preparations of the enzyme. The production of the oxidase through fed-batch bioreactor culture and subsequent cell permeabilization is high-yielding and efficient. Therefore this P. pastoris catalyst has been evaluated for industrial purposes.

The role of vascularization in 3-D tissue engineering

The role of vascularization in 3-D tissue engineering was studied. Mouse fat, angiogenic growth factors, adult human stem cells and fat tissue have been inserted and subsequent tissue growth was monitored. Human fat grafts or human lipoaspirates in SCID mouse chambers induced mouse fat generation at 6 weeks. Tissue engineering models utilizing intrinsic vascularization have major advantages including rapid and appropriate vascularization of new tissues.

Rapid on-site evaluation of fine needle aspiration specimens by cytology scientists : a review of 3032 specimens

Objectives To determine: (1) the accuracy of cytology scientists at assessing specimen adequacy by rapid on-site evaluation (ROSE) at fine needle aspiration (FNA) cytology collections; and (2) whether thyroid FNA with ROSE has lower inadequacy rates than non-attended FNAs. Methods The ROSE of adequacy for 3032 specimens from 17 anatomical sites collected over a 20-month period was compared with the final report assessment of adequacy. ROSE was performed by 19 cytology scientists. The report profile for 1545 thyroid nodules with ROSE was compared with that for 1536 consecutive non-ROSE thyroid FNAs reported by the same cytopathologists during the study period. Results ROSE was adequate in 75% (2276/3032), inadequate in 12% (366/3032) and in 13% (390/3032) no opinion was rendered. Of the 2276 cases assessed as adequate by ROSE, 2268 (99.6%) were finally reported as adequate for assessment; eight specimens had adequacy downgraded on the final report. Fifty eight per cent of cases with a ROSE assessment of inadequate were reported as adequate (212/366), whereas 93% (363/390) with no opinion rendered were reported as adequate. The overall final report adequacy rate for the 3032 specimens was 94% (2843/3032). Confirmation of a ROSE of adequacy at reporting was uniformly high amongst the 19 scientists, ranging from 98% to 100%. The inadequacy rate for thyroid FNAs with ROSE (6%) was significantly (P < 0.0001) lower than for non-ROSE thyroid FNAs (17%). A significantly (P = 0.02) higher proportion of adequate ROSE thyroid specimens was reported with abnormalities, compared with non-ROSE thyroid collections. Conclusions Cytology scientists are highly accurate at determining specimen adequacy at ROSE for a wide range of body sites. ROSE of thyroid FNAs can significantly reduce inadequate reports.

Serum 25-hydroxy vitamin D concentrations are more deficient/insufficient in peritoneal dialysis than haemodialysis patients in a sunny climate

Background Research has identified associations between serum 25(OH)D and a range of clinical outcomes in chronic kidney disease and wider populations. The present study aimed to investigate vitamin D deficiency/insufficiency in dialysis patients and the relationship with vitamin D intake and sun exposure. Methods A cross-sectional study was used. Participants included 30 peritoneal dialysis (PD) (43.3% male; 56.87 ± 16.16 years) and 26 haemodialysis (HD) (80.8% male; 63.58 ± 15.09 years) patients attending a department of renal medicine. Explanatory variables were usual vitamin D intake from diet/supplements (IU day−1) and sun exposure (min day−1). Vitamin D intake, sun exposure and ethnic background were assessed by questionnaire. Weight, malnutrition status and routine biochemistry were also assessed. Data were collected during usual department visits. The main outcome measure was serum 25(OH)D (nm). Results Prevalence of inadequate/insufficient vitamin D intake differed between dialysis modality, with 31% and 43% found to be insufficient (<50 nm) and 4% and 33% found to be deficient (<25 nm) in HD and PD patients, respectively (P < 0.001). In HD patients, there was a correlation between diet and supplemental vitamin D intake and 25(OH)D (ρ = 0.84, P < 0.001) and average sun exposure and 25(OH)D (ρ = 0.50, P < 0.02). There were no associations in PD patients. The results remained significant for vitamin D intake after multiple regression, adjusting for age, gender and sun exposure. Conclusions The results highlight a strong association between vitamin D intake and 25(OH)D in HD but not PD patients, with implications for replacement recommendations. The findings indicate that, even in a sunny climate, many dialysis patients are vitamin D deficient, highlighting the need for exploration of determinants and consequences.

Adsorption of the herbicide 2,4-D on organo-palygorskite

Among the clay minerals, montmorillonite is the most extensively studied material using as adsorbents, but palygorskite and its organically modified products have been least explored for their potential use in contaminated water remediation. In this study, an Australian palygorskite was modified with cationic surfactants octadecyl trimethylammonium bromide and dioctadecyl dimethylammonium bromide at different doses. A full structural characterization of prepared organo-palygorskite by X-ray diffraction, infrared spectroscopy, surface analysis and thermogravimetric analysis was performed. The morphological changes of palygorskite before and after modification were recorded using scanning electron microscopy, which showed the surfactant molecules can attach on the surface of rod-like crystals and thus can weaken the interactions between palygorskite single crystals. Real surfactants loadings on organo-palygorskites were also calculated based on thermogravimetric analysis. 1 CEC, 2 CEC octadecyl trimethylammonium bromide modified palygorskites, 1 CEC and 2 CEC dioctadecyl dimethylammonium bromide modified palygorskites absorbed as much as 12 mg/g, 42 mg/g, 9 mg/g and 25 mg/g of 2,4- dichlorophenoxyacetic acid respectively. This study has shown a potential on organo-palygorskites for organic herbicide adsorption especially anionic ones from waste water. In addition, equilibration time effects and the Langmuir and Freundlich models fitting were also investigated in details.

Synthesis, characterization and comparative study of thiophene- benzothiadiazole based donor-acceptor-donor (D-A-D) materials

The synthesis and characterization of solution processable donor-acceptor-donor (D-A-D) based conjugated molecules with varying ratios of thiophene as donor (D) and benzothiadiazole as acceptor (A) are reported. Optical, electrochemical, thermal, morphological and organic thin film transistor (OTFT) device properties of these materials were investigated. The thermal and polarized optical microscope analysis indicates that the materials having higher D/A ratios exhibit both liquid crystalline (LC) and OTFT behavior. AFM analysis of the materials having D/A ratios of 3 and 4 (3T1B and 4T1B) show well ordered structures, resulting from strong π-π interchain interactions compared to the other molecules in this study. A XRD patterns for 3T1B and 4T1B thin films also shows high crystalline ordering. Solution processed OTFTs of 3T1B and 4T1B have shown un-optimized charge carrier mobilities of 2 × 10 -2 cm 2 V -1 s -1 and 4 × 10 -3 cm 2 V -1 s -1, respectively on bare Si/SiO 2 substrate.

Thiophene-benzothiadiazole-thiophene (D-A-D) based polymers : Effect of donor/acceptor moieties adjacent to D-A-D segment on photophysical and photovoltaic properties

New push-pull copolymers based on thiophene (donor) and benzothiadiazole (acceptor) units, poly[4,7-bis(3-dodecylthiophene-2-yl) benzothiadiazole-co- thiophene] (PT3B1) and poly[4,7-bis(3-dodecylthiophene-2-yl) benzothiadiazole-co-benzothiadiazole] (PT2B2), are designed and synthesized via Stille and Suzuki coupling routes respectively. Gel permeation chromatography shows the number average molecular weights are 31100 and 8400 g mol-1 for the two polymers, respectively. Both polymers have shown absorption throughout a wide range of the UV-vis region, from 300 to 650 nm. A significant red shift of the absorption edge is observed in thin films compared to solution of the copolymers; the optical band gap is in the range of 1.7 to 1.8 eV. Cyclic voltammetry indicates reversible oxidation and reduction processes with HOMO energy levels calculated to be in the range of 5.2 to 5.4 eV. Upon testing both materials for organic field-effect transistors (OFETs), PT3B1 showed a hole mobility of 6.1 × 10-4 cm2 V-1 s -1, while PT2B2 did not show any field effect transport. Both copolymers displayed a photovoltaic response when combined with a methanofullerene as an electron acceptor. The best performance was achieved when the copolymer PT3B1 was blended with [70]PCBM in a 1:4 ratio, exhibiting a short-circuit current of 7.27 mA cm-2, an open circuit voltage of 0.85 V, and a fill factor of 41% yielding a power conversion efficiency of 2.54% under simulated air mass (AM) 1.5 global (1.5 G) illumination conditions (100 mW cm-2). Similar devices utilizing PT2B2 in place of PT3B1 demonstrated reduced performance with a short-circuit current of 4.8 mA cm -2, an open circuit voltage of 0.73 V, and a fill factor of 30% resulting in a power conversion efficiency of roughly 1.06%.