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© 2019, Akadémiai Kiadó, Budapest, Hungary. Low-temperature DSC on a wide range of opal-A and opal-CT samples was carried out to estimate the proportion of crystallisable water and to determine the size of water-filled cavities. A wide range of crystallisable water contents in the range 4.9 to 41.9% of the water contained in opals were observed, although the proportion of crystallisable water did not correlate with structure. Pore size and pore size distribution were estimated from the melt temperature depression and heat flow data, respectively. Opal-CT was observed to have smaller water-filled pores (radii < 2 nm) than opal-A (radii from 2.5 to 4.9 nm), suggesting that molecular water may be contained between nanograins in the microstructural units (spheres or lepispheres). A narrower pore size distribution was calculated for opal-CT, and no melting of the crystallisable water was observed where bulk water would be expected to melt, suggesting the absence of larger voids. The melting peaks for opal-A, on the other hand, transitioned into the melting of bulk water suggesting the presence of significantly larger water-filled pores, an observation consistent with the microstructure observed in SEM micrographs.

Air pollution is a ubiquitous problem and comprises gaseous and particulate matter (PM). Epidemiological studies have clearly shown that exposure to PM is associated with impaired lung function and the development of lung diseases, such as chronic obstructive pulmonary disease and asthma. To understand the mechanisms involved, animal models are often used. However, the majority of such models represent high levels of exposure and are not representative of the exposure levels in less polluted countries, such as Australia. Therefore, in this study, we aimed to determine whether low dose PM10 exposure has any detrimental effect on the lungs. Mice were intranasally exposed to saline or traffic-related PM10 (1μg or 5μg/day) for 3 wk. Bronchoalveolar lavage (BAL) and lung tissue were analyzed. PM10 at 1 μg did not significantly affect inflammatory and mitochondrial markers. At 5 μg, PM10 exposure increased lymphocytes and macrophages in BAL fluid. Increased NACHT, LRR and PYD domains-containing protein 3 (NLRP3) and IL-1β production occurred following PM10 exposure. PM10 (5 μg) exposure reduced mitochondrial antioxidant manganese superoxide (antioxidant defense system) and mitochondrial fusion marker (OPA-1), while it increased fission marker (Drp-1). Autophagy marker light-chain 3 microtubule-associated protein (LC3)-II and phosphorylated-AMPK were reduced, and apoptosis marker (caspase 3) was increased. No significant change of remodeling markers was observed. In conclusion, a subchronic low-level exposure to PM can have an adverse effect on lung health, which should be taken into consideration for the planning of roads and residential buildings.

RATIONALE: Childhood risk factors for long-term lung health often co-exist and their specific patterns may affect subsequent lung function differently. OBJECTIVES: To identify childhood risk factor profiles, their influence on lung function and chronic obstructive pulmonary disease (COPD) in middle-age and potential pathways. METHODS: Profiles of 11 childhood respiratory risk factors, documented at age 7, were identified in 8352 participants from the Tasmanian Longitudinal Health Study using latent class analysis. We investigated: associations between risk profiles and lung function, and COPD at age 53; mediation by childhood lung function and adult asthma; and interaction with personal smoking. RESULTS: Six risk profiles were identified: 1-"unexposed or least exposed" (49%), 2-"parental smoking" (21.5%), 3-"allergy" (10%), 4-"frequent asthma, bronchitis" (8.7%), 5-"infrequent asthma, bronchitis" (8.3%) and 6-"frequent asthma, bronchitis, allergy" (2.6%). Profile 6 was most strongly associated with lower FEV1:(-261;95%CI:-373,-148 mL); lower FEV1/FVC:(-3.4; -4.8,-1.9%) and increased COPD risk (OR:4.9; 2.1,11.0) at age 53. The effect of profile 6 on COPD was largely mediated by adult active asthma (62.5%) and reduced childhood lung function (26.5%). Profiles 2 and 4 had smaller adverse effects than profile 6. Notably effects of profiles 2 and 6 were stronger for smokers. CONCLUSIONS: Profiles of childhood respiratory risk factors predict middle-age lung function and COPD risk. Adult active asthma is a dominant mediator in associations between childhood asthma-related risk profiles and middle-age lung function/COPD. Specifically, children with frequent asthma attacks and allergies, especially if they also become adult smokers, are the most vulnerable group that should be targeted for interventions.

RATIONALE: There are limited data on early life risk factors for COPD phenotypes. OBJECTIVE: To investigate the role of childhood lung function in adult spirometrically defined COPD phenotypes. METHOD: Pre-bronchodilator (BD) spirometry was performed for a cohort of 7-year old Tasmanian children. A sub-sample underwent pre-and post-BD spirometry at 45 years. For this analysis, COPD was spirometrically defined as a post-BD FEV1/FVC

BACKGROUND The safe and appropriate use of long-acting beta-agonists (LABAs) for the treatment of asthma has been widely debated. In two large clinical trials, investigators found a potential risk of serious asthma-related events associated with LABAs. This study was designed to evaluate the risk of administering the LABA salmeterol in combination with an inhaled glucocorticoid, fluticasone propionate. METHODS In this multicenter, randomized, double-blind trial, adolescent and adult patients (age, ≥12 years) with persistent asthma were assigned to receive either fluticasone with salmeterol or fluticasone alone for 26 weeks. All the patients had a history of a severe asthma exacerbation in the year before randomization but not during the previous month. Patients were excluded from the trial if they had a history of lifethreatening or unstable asthma. The primary safety end point was the first serious asthma-related event (death, endotracheal intubation, or hospitalization). Noninferiority of fluticasone–salmeterol to fluticasone alone was defined as an upper boundary of the 95% confidence interval for the risk of the primary safety end point of less than 2.0. The efficacy end point was the first severe asthma exacerbation. RESULTS Of 11,679 patients who were enrolled, 67 had 74 serious asthma-related events, with 36 events in 34 patients in the fluticasone–salmeterol group and 38 events in 33 patients in the fluticasone-only group. The hazard ratio for a serious asthmarelated event in the fluticasone–salmeterol group was 1.03 (95% confidence interval [CI], 0.64 to 1.66), and noninferiority was achieved (P = 0.003). There were no asthma-related deaths; 2 patients in the fluticasone-only group underwent asthmarelated intubation. The risk of a severe asthma exacerbation was 21% lower in the fluticasone–salmeterol group than in the fluticasone-only group (hazard ratio, 0.79; 95% CI, 0.70 to 0.89), with at least one severe asthma exacerbation occurring in 480 of 5834 patients (8%) in the fluticasone–salmeterol group, as compared with 597 of 5845 patients (10%) in the fluticasone-only group (P

Vitamin D deficiency is a potentially modifiable risk factor that may be targeted for breast cancer prevention. We examinedthe safety, feasibility, and biomarker effects of high-dose vitamin D among women at high risk for breast cancer. Forty high-risk women, defined as a 5-year breast cancer risk ≥1.67% per the Gail model, lobular or ductal carcinoma in situ, wereassigned to a 1-year intervention of vitamin D3 20,000 IU or 30,000 IU weekly. Participants were monitored for toxicityevery 3 months, underwent serial blood draws at baseline, 6 and 12 months, and a digital mammogram at baseline and 12months. Biomarker endpoints included serum 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25(OH)2D],parathyroid hormone (PTH), insulin-like growth factor (IGF-1), IGF binding protein (IGFBP-3), and mammographicdensity (MD) using Cumulus software. From November 2007 to January 2011, we enrolled 40 women; 37 were evaluableat 6 months and 30 at 12 months. One patient was taken off study for hypercalciuria; otherwise, the intervention was welltolerated. From baseline to 12 months, mean serum 25(OH)D and 1,25(OH)2D rose from 20.0 to 46.9 ng/ml and 69.7to 98.1 pg/ml, respectively (p

Samples of electrolytic manganese dioxide (EMD) were chemically reduced using 2-propanol under reflux (82°C) for 1, 2, 3, 6 and 24 h intervals. XRD analysis showed that the γ-MnO2 structure was preserved although the lattice dimensions were observed to increase with increasing degree of reduction to accommodate the intercalation of protons. The exception was the 24 h reduced sample which contained two phases; γ -MnO2 and γ -MnOOH. Three regions of decomposition in the range of 50 to 1000°C were observed using thermogravimetric analysis coupled with mass spectrometry (TG-MS) and were accounted for as water removal below 390°C, reduction of MnO2 to Mn2O3 between 400 and 600°C, and Mn2O3 to Mn3O4 between 600 and 1000°C. Again the exception proved to be the 24 h reduced sample which was observed to decompose predominantly in one step between 400 and 600°C directly to Mn3O4. © 2005 Akadémiai Kiadó Budapest.

Portland cement (PC) is one of the world's most important building materials, as it is a fundamental component of concrete. However, the manufacture of PC is highly energy intensive and leads to the emission of carbon dioxide (CO2). One promising control measure is the use of industrial wastes and by-products as supplementary cementing materials (SCMs) in order to minimise PC consumption, thereby producing greener cement-based products. This study investigates mechanical properties and phase development of hydrothermally treated cement-ground quartz sand blends with the incorporation of fired clay-brick (CB) waste and reactive magnesia (MgO). The addition of CB waste in autoclaved PC-quartz mortar mixes showed that the alumina-silica rich CB waste was pozzolanic when the Al2O3 accelerated formation and increased crystallinity of Al substituted 1.1 nm tobermorite, resulting in the observed strength gain. Autoclaved mortar specimens incorporating reactive MgO showed a reduction in strength with increasing MgO addition. This was a result of dilution when the relative proportion of PC available for the formation of the strength contributing hydration products including tobermorite is decreased.

The mechanism and stability of dimethylol urea (DMU) to polycondensation were investigated using thermogravimetric analysis coupled with mass spectroscopy (TG-MS) for evolved gas analysis and a non-isothermal model-free induction period kinetic analysis using three temperature functions; the Arrhenius function and two non-Arrhenian functions. The polycondensation was observed to occur through a two-step process of condensation followed by elimination of formaldehyde during structural rearrangement as has been reported in the literature. The rate equations for each temperature function were evaluated and extrapolated to room (23 °C) and refrigerator (4 °C) temperature to estimate the length of the induction period for the onset of polycondensation for storage life prediction. Based on experience, estimates of the length of the induction periods and, hence, storage life, were most realistically predicted by the non-Arrhenian temperature functions. © Akadémiai Kiadó, Budapest, Hungary 2011.

The deleterious interaction of some traditional sulphide artists pigments and copper ions results in the formation of black copper sulphides, in particular, covellite (CuS), and, hence, the discolouration of valuable artworks. In this paper the interaction of malachite, a source of copper(II) ions, with the pigment cadmium yellow, a sulphide pigment comprising of a solid solution of cadmium and zinc sulphides, is investigated by XRD and TG-MS. XRD showed the presence of the copper sulphide and cadmium carbonate phases, produced by a simple ion exchange mechanism. TG-MS showed the complexity of the range of metastable phases produced. The identification of these phases, however, requires further work. © Springer-Verlag 2007.

Cold pressed linseed oil and paints prepared using the inorganic pigments; lead white and red lead, were characterized using non-isothermal differential scanning calorimetry (DSC) in an air atmosphere to determine the effect of the pigment on the oxidative polymerisation of the drying oil medium. For each paint sample, the onset temperature for oxidation was reduced from 166°C to the range 50 to 60°C when a heating rate of 5 K min-1 was used. In order to determine the rate of drying, the non-isothermal experiments were carried out using a range of heating rates. A change in the mechanism oxidative polymerization was observed as the heating rate was increased. © 2005 Akadémiai Kiadó, Budapest.

Four opal-AG (amorphous) and two opal-CT (paracrystalline) samples obtained from various regions in Australia were investigated with 29Si NMR and 27Al NMR. The proton cross-polarization 29Si NMR technique was used and the resulting spectra consisted of two main resonances: -102.0 and -111.2 ppm for opal-AG; and -102.5 and -112.2 ppm for opal-CT. These peaks were assigned to the Q3(1OH) and Q 4 resonances, respectively. Using very short contact times, a third, very weak peak at -94 ppm was resolved in an opal-CT specimen, which was assigned to silicon in the Q2(2OH) arrangement (i.e. a silicon with twin hydroxyl groups). It was found that the opal-CT samples contained a higher proportion of both geminal and vicinal silanol groups (Q2 and Q 3) than the opal-AG samples. The geminal silanol groups present in opal-AG and opal-CT are not restricted to opal-AN. The full-width at half-maximum (FWHM) values were 9.5 ppm for the opal-AG samples, and 6.5 ppm for both opal-CT samples, a result which confirms that opal-CT has a higher degree of short-range structural order than opal-AG. The 27Al NMR spectra of the opals all showed a single resonance at +52 ppm, indicating that the aluminium exists in a tetrahedral arrangement incorporated within the opal structure. © 2003 Elsevier B.V. All rights reserved.

The DSC characterisation of the morphology of the metastable a phase of stoichiometric nickel sulphide was carried out using two calorimeters; a TA Instruments 2920 MDSC and a Perkin Elmer DSC-7, and two quenching histories. Based on these quenching histories, significant differences were observed in the heat flow curves, including the observation of a second exothermic peak which is tentatively assigned to be a metastable phase to metastable phase transformation. The kinetic constants for the α to β recrystallisation were determined as a function of degree of conversion using a mechanism free isoconversional model. Variations in the values of the kinetic constants were also ascribed to the quenching histories. Although the differences in morphology observed were ascribed to the processing history, the shift in the position of the α to β recrystallisation peak was partially attributed to the thermal resistances of the instruments used.

Museum specimens of pyrite are known to undergo oxidation even during storage. Characterisation of the oxidation products is however not always simple due to amorphous character and varying degrees of hydration of the oxidation products, This paper presents an alternative approach to the characterisation of oxidation products by identifying their presence from their characteristic thermal decomposition processes using thermogravimetric and evolved gas analysis. Four pyrite specimens were characterised with varying degrees of oxidation. Iron(II) and iron(III) sulphates were also characterised for comparative purposes. The degradation products were observed to correlate well with the presence of iron(II) sulphate even though there was found to be some discrepancy in the higher temperature decomposition reactions.

An incremental integral isoconversional method for the determination of activation energy as a function of the extent of conversion is presented. The method is based on the treatment of experimental data without their transformation so that the resulting values of activation parameters should not be biased. The method was tested for recovering the activation energies from simulated data and employed for the treatment of experimental data of the NiS recrystallisation.

Compression moulded plaques of a range of poly(ether ether ketone) (PEEK)- poly(tetrafluoroethylene) (PTFE) blends (100, 92, 48, 29, 9.5 and 0 mass% PEEK) have been characterised using differential scanning calorimetry (DSC) and wide angle X-ray crystallography (WAXD). A shift in the melting peak of the PEEK phase from 347 to 358°C was observed with increasing proportion of PTFE in the blend. A narrowing of the melting range was also observed. Correspondingly, WAXD measurements showed a reduction in the d-spacings. The observed changes in morphology are rationalised in terms of a higher degree of order imparted on the PEEK crystalline phase by the transmission of an applied 'hydrostatic' pressure by the presence of the PTFE.

Naturally occurring opals from three different regions in Australia were studied for their thermal characteristics. All the opals showed initial expansion followed by contraction in thermomechanical analysis (TMA) although the temperature at which the change from expansion to contraction occurred depended on their provenance. Thermogravimetric analysis (TG) revealed different rates and temperatures of dehydration for these opals. A general correlation between the temperature at which there was a zero thermal expansion and that of the maximum rate of dehydration was observed. A dehydration-sintering mechanism is proposed with the effect of sintering being more pronounced following total dehydration.

The degradation of poly(vinyl alcohol) was investigated using TG analysis and Fourier transform infrared spectroscopy to determine the effect of atmosphere on the process of degradation. In the spectra, four vibrational modes were identified that characterised the major steps of the degradation process. These were the O-H, C-H, C=O and C=C stretching modes. The mechanism observed for degradation in an inert atmosphere was in accordance with the accepted mechanism of elimination followed by pyrolisation. Evidence of conjugated polyenes, however, was not observed. For the air atmosphere, oxidation in both steps of the degradation process was observed.

Toughened glass panels used as a glazing material in multistorey buildings are known to fracture prematurely when they contain nickel sulfide inclusions as a result of the α-β phase recrystallisation in nickel sulfide. The kinetics of this recrystallisation were studied by differential scanning calorimetry (DSC) under isothermal and non-isothermal conditions. The recrystallisation was observed to be a two-step process with an induction period followed by the phase change. A two-stage kinetic model was used to estimate the recrystallisation time under ambient conditions. These values were found to correlate well with the observed time to failure for glass panels installed in multistorey buildings.

We have isolated a cDNA that encodes the human regulatory myosin light chain isoform predominant in adult atrial muscle. The cDNA contains an open reading frame of 175 amino acids and encodes a hydrophilic protein of a largely helical structure with two potential phosphorylation sites. The protein is different from any other regulatory myosin light chain so far described and is the product of a previously uncharacterized single copy gene. An isoform-specific probe was used to analyze the expression of this isoform in adult muscle and in cardiac and skeletal muscle development in vivo and in vitro. Parallel analysis of the corresponding human alkali myosin light chain (predominant in adult atrium) showed that both isoforms are expressed in early heart development, in both atrium and ventricle. Although the atrial alkali light chain is expressed throughout embryonic striated muscle development, the regulatory myosin light chain was not detected in skeletal myogenesis in vivo or in vitro. Thus the atrial isoforms are not universally or exclusively "paired" and can be independently regulated. We propose that the manner in which these particular isoforms fulfill the functional requirements of the muscle at different developmental times may have direct impact on their regulation.