673 resultados para Mucin-2
Resumo:
Bermanite Mn2þMn3þ2 ðPO4Þ2ðOHÞ2 � 4ðH2OÞ is a mixed valent hydrated hydroxy phosphate mineral. The mineral is reddish-brown and occurs in crystal aggregates and as lamellar masses. Bermanite is a common mineral in granitic pegmatites. The chemical composition of bermanite was obtained using EDS techniques. We have studied the molecular structure of bermanite using vibrational spectroscopy. The mineral is characterized by a Raman doublet at 991 and 999 cm-1 attributed to the phosphate stretching mode of two non-equivalent phosphate units. Raman bands at 1071, 1117 and 1142 cm-1 are assigned to the phosphate antisymmetric stretching modes. The hydroxyl stretching spectral region is complex with overlapping bands attributed to water and hydroxyl stretching vibrations. Vibrational spectroscopy proves most useful for the study of the mineral bermanite.
Resumo:
Raman spectroscopy complimented with infrared spectroscopy has been used to determine the molecular structure of the phosphate mineral fairfieldite. The Raman phosphate (PO4)3- stretching region shows strong differences between the fairfieldite phosphate minerals which is attributed to the cation substitution for calcium in the structure. In the infrared spectra complexity exists with multiple (PO4)2- antisymmetric stretching vibrations observed, indicating a reduction of the tetrahedral symmetry. This loss of degeneracy is also reflected in the bending modes. Strong Raman bands around 600 cm-1 are assigned to v4 phosphate bending modes. Multiple bands in the 400–450 cm-1 region assigned to m2 phosphate bending modes provide further evidence of symmetry reduction of the phosphate anion. Three broadbands for fairfieldite are found at 3040, 3139 and 3271 cm-1 and are assigned to OH stretching bands. By using a Libowitzky empirical equation hydrogen bond distances of 2.658 and 2.730 A are estimated. Vibrational spectroscopy enables aspects of the molecular structure of the fairfieldite to be ascertained.
Resumo:
Whether to keep products segregated (e.g., unbundled) or integrate some or all of them (e.g., bundle) has been a problem of profound interest in areas such as portfolio theory in finance, risk capital allocations in insurance and marketing of consumer products. Such decisions are inherently complex and depend on factors such as the underlying product values and consumer preferences, the latter being frequently described using value functions, also known as utility functions in economics. In this paper, we develop decision rules for multiple products, which we generally call ‘exposure units’ to naturally cover manifold scenarios spanning well beyond ‘products’. Our findings show, e.g. that the celebrated Thaler's principles of mental accounting hold as originally postulated when the values of all exposure units are positive (i.e. all are gains) or all negative (i.e. all are losses). In the case of exposure units with mixed-sign values, decision rules are much more complex and rely on cataloging the Bell number of cases that grow very fast depending on the number of exposure units. Consequently, in the present paper, we provide detailed rules for the integration and segregation decisions in the case up to three exposure units, and partial rules for the arbitrary number of units.
Resumo:
This study used data from Growing Up in Australia: The Longitudinal Study of Australian Children (LSAC) to investigate how parent report of children’s emotional and cognitive regulation at age 2-3 years was associated with teacher ratings of children’s prosocial behaviors in the early years of school. A sample of 2,392 children was drawn from the LSAC Birth Cohort for the analyses. The analyses used structural equation modeling to estimate parameters of the relationships between key variables. Within the model, estimates of mother-reported emotional and cognitive regulation at age 2 to 3 years were significantly associated with teacher-reported prosocial behavior at 6 to 7 years. Emotional regulation was a slightly stronger indicator of prosocial behavior than cognitive regulation. Being female and from a family with a higher socioeconomic position were also associated with higher levels of prosocial behavior. Results are discussed in relation to the role of early childhood teachers in fostering children’s self-regulatory behaviors and in providing environments in which empathic and prosocial behaviors are modeled, guided, and scaffolded so that foundations are laid for caring behaviors to be understood and internalized by children.
Resumo:
Although the adoption of Enterprise Web 2.0 within organisations is beneficial, it could meet with employees’ resistance and the adoption process can be lengthy. The successful implementation of Enterprise Web 2.0 is based on employee involvement and adoption of such social technology. This paper is part of a larger research project that explored the adoption of Web 2.0 by individuals within enterprises. Using a qualitative study, the findings show that there are number of adoption influences including technological, individual and contextual issues. This paper presents Web 2.0 technological attributes that influence its adoption. The found attributes are: friendliness, reliability, mobility, technical compatibility, discoverability, transparency and Web 2.0 type.
Resumo:
The mineral olshanskyite is one of many calcium borate minerals which has never been studied using vibrational spectroscopy. The mineral is unstable and decomposes upon exposure to an electron beam. This makes the elemental analysis using EDX techniques difficult. Both the Raman and infrared spectra show complexity due to the complexity of the structure. Intense Raman bands are found at 989, 1,003, 1,025 and 1,069 cm-1 with a shoulder at 961 cm-1 and are assigned to trigonal borate units. The Raman bands at 1,141, 1,206 and 1,365 cm-1 are assigned to OH in-plane bending of BOH units. A series of Raman bands are observed in the 2,900–3,621cm-1 spectral range and are assigned to the stretching vibrations of OH and water. This complexity is also reflected in the infrared spectra. Vibrational spectroscopy enables aspects of the structure of olshanskyite to be elucidated.
Resumo:
We have studied the mineral goyazite using Raman and infrared spectroscopy. Goyazite is a member of the crandallite subgroup of the alunite supergroup. The crystal structure is of the alunite-type and consists of sheets of corner-sharing AlO6 octahedra parallel to (0001). The octahedrally coordinated Sr2+ cations occupy cavities between pairs of octahedral sheets and are surrounded by six oxygen atoms from the (Al3+)O6 octahedra. The very intense sharp band at 983 cm-1 is assigned to the ν1 PO43- symmetric stretching mode. The observation of a single band supports the concept that all the phosphate units are equivalent in the structure of goyazite. Raman bands observed at 1029 cm-1 and 1037 cm-1 are assigned to the to the ν3 PO43- antisymmetric stretching vibrations. Two Raman bands at 895 and 927 cm-1 are attributed to the stretching vibrations of H2PO4; thus indicating some hydrogen phosphate units in the structure of goyazite. Raman bands at 556, 581, 596 and 612 cm-1 are assigned to the ν4 PO43- bending modes, suggesting a reduction of symmetry of phosphate units. Two sharp Raman bands at 3609 and 3631 cm-1 are attributed to OH stretching vibrations from the goyazite hydroxyl units. Broad Raman bands at 2924, 3043, 3210, 3429 and 3511 cm-1 are assigned to water stretching vibrations. Vibrational spectroscopy enables subtle details of the molecular structure of goyazite to be determined.
Resumo:
Currently there is a lack of choice when selecting synthetic materials with the cell-instructive properties demanded by modern biomaterials. The purpose of this study was to investigate the attachment of cells onto hydrogels prepared from poly(2-oxazoline)s selectively-functionalized with cell adhesion motifs. A water-soluble macromer based on the microwave-assisted cationic ring-opening polymerization of 2-methyl-2-oxazoline and 2-(dec-9-enyl)-2-oxazoline was functionalized with the peptide CRGDSG or controls using thiol-ene photochemistry followed by facile crosslinking in the presence of a dithiol crosslinker. The growth of human fibroblasts on the hydrogel surfaces was dictated by the structure and amount of incorporated peptide. Controls without any peptide showed resistance to cellular attachment. The benignity of the crosslinking conditions was demonstrated by the incorporation of fibroblasts within the hydrogels to produce three-dimensional cell-polymer constructs.
Resumo:
This study explores and evaluates students’ and teachers’ experiences when using a range of Web 2.0 tools in Higher Education teaching and learning. It contributes to our understanding of how Web 2.0 learning communities are constructed, experienced and the nature of the participation therein. This research extends our knowledge and understanding of the Web 2.0 phenomena, and provides a framework that can assist with improving future Web 2.0 implementation.
Resumo:
FTIR spectra are reported of methanol adsorbed at 295 K on ZnO/SiO 2, on reduced Cu/ZnO/SiO2 and on Cu/ZnO/SiO2 which had been preoxidised by exposure to nitrous oxide. Methanol on ZnO/SiO2 gave methoxy species on ZnO and SiO, in addition to both strongly and weakly physisorbed methanol on SiO2. The corresponding adsorption of methanol on reduced Cu/ZnO/SiO2 also gave methoxy species on Cu and a small amount of bridging formate. Reaction of methanol with a reoxidised Cu/ZnO/SiO2 catalyst resulted in an enhanced quantity of methoxy species on Cu. Heating adsorbed species on Cu/ZnO/SiO2 at 393 K led to the loss of methoxy groups on Cu and the concomitant formation of formate species on both ZnO and Cu. The comparable reaction on a reoxidised Cu/ZnO/SiO2 catalyst gave an increased amount of formate species on ZnO and this correlated with an increased quantity of methoxy groups lost from Cu. An explanation is given in terms of adsorption of formate and formaldehyde species at special sites located at the copper/zinc oxide interface.
Resumo:
At NTCIR-10 we participated in the cross-lingual link discovery (CrossLink-2) task. In this paper we describe our systems for discovering cross-lingual links between the Chinese, Japanese, and Korean (CJK) Wikipedia and the English Wikipedia. The evaluation results show that our implementation of the cross-lingual linking method achieved promising results.
Resumo:
The concept of Library 2.0 with its participatory and user-centred focus increasingly has been incorporated in library practice around the world. However, research on this topic is either limited or non-existent in developing countries which are often restricted by tight budgets and varying levels of technological infrastructure. This poster presents the findings of an ongoing pilot project which investigates Library 2.0 in the specific cultural context of Indonesia as well as strengthens the general evidence base in this research area. Data was collected through an online survey with library and information (LIS) professionals from across the information sector in Indonesia. Quantitative and qualitative methods were used to explore their understanding of the concept of Library 2.0. The preliminary data collected from this study will be used to inform a more complex future research project. As well, findings are intended to aid in LIS curriculum development in Indonesia to support the education of LIS students.
Resumo:
Asthma is an incapacitating disease of the respiratory system, which causes extensive morbidity and mortality worldwide. Asthma affects more than 300 million people globally(Masoli et al. 2004). In Australia, it affects 10.2% of the population (Masoli et al. 2004) and causes 60,000 people to be hospitalised annually. Health care expenditure due to asthma in Australia was $606 million in 2004–2005. There are four primary biological factors that function in the initiation and exacerbation of asthma. Airway inflammation is important as it is often the first response to an airway insult, initiating the three other components: bronchoconstriction, mucus hyper-secretion and hyper-reactivity. The mediators involved in asthma are still not well understood, and current anti-inflammatory corticosteroid treatments are not effective with all asthmatics. As there is currently no cure for asthma, and airway inflammation is the primary component of the disease, it is important that we understand and investigate the mediators of airway inflammation to look for a potential cure and to produce better therapeutics to treat the inflammation. Trefoil factors (TFFs) and secretoglobins (SCGBs) are small secreted proteins involved in the mediation of inflammation and epithelial restitution. TFFs are pro-inflammatory and SCGBs anti-inflammatory by nature. The hypothesis of this study is that in response to induced acute airway inflammation, the expression of TFF1 and TFF3 will increase and expression of SCGB1A1 and SCGB3A2 will decrease in non-asthmatics (N-A), asthmatics medicating with bronchodilators (A-BD) and asthmatics medicating with corticosteroids (A-ST). When comparing the three groups, we expect to see higher expression of the TFFs in the A-BD group compared to the N-A and A-ST groups, indicating that inflammation is mediated by TFFs in asthma and that corticosteroid medication controls their expression as part of the control of inflammation. We expect to see the opposite with SCGBs, with a greater decrease in the A-BD group compared to the other two groups, suggesting that the A-BD group has the least anti-inflammatory activity in response to inflammatory insult. Epigenetic modification plays a role in the regulation of genes that initiate disease states such as inflammatory conditions and cancers. Histone acetylation is one such modification, which involves the acetylation of histones in chromatin by histone acetyltransferases (HATs). This increases the transcription of genes involved with inflammation or enrols histone deacetylases (HDACs) to down-regulate the transcription of inflammatory genes. These HATs and HDACs work in a homeostatic fashion; however, in the event of inflammation, increased HAT activity can stimulate further inflammation, which is believed to be the mechanism involved in some inflammatory diseases. This study hypothesises that in response to inflammation, the expression of HDACs (HDAC1-5) will decrease and the expression of HATs (NCOA1-3, HAT-1 and CREBBP) will increase in all groups. When comparing the expression between the groups, it was expected that a greater decrease in HDACs and a greater increase in HATs will be seen in the A-BD group compared to the other two groups. This would identify histone acetylation as a mechanism involved in the inflammatory condition of asthma and indicate that corticosteroids may treat the inflammation in asthma at least in part by controlling histone acetylation. The aim of the project was to compare the expression of inflammatory genes TFF1, TFF3, SCGB1A1 and SCGB3A2, as well as to compare the gene expression of HDAC1-5, NCOA1-3, HAT-1 and CREBBP within and between N-A (n=15), A-BD (n=15) and A-ST (n=15) groups in response to inflammation. This was performed by collecting airway cells and proteins by sputum induction in three sessions. The sessions were coordinated into an initial baseline collection (SI-1), followed by a second session at least one week later (SI-2) and a third session, six hours after SI-2 to collect a sample containing the resultant acute inflammation caused in SI-2 (SI-3). Analysis of the SI-1 and SI-2 samples in all three groups had high amounts of variability between samples. The samples were taken at least one weak apart and the environmental stimuli on each participant outside of the testing sessions could not be controlled. For this reason, the SI-1 samples were not used for analysis; instead SI-2 and SI-3 samples were compared as they were same-day collections, reducing the probability of differences being due to anything other than the sputum induction. The gene expressions of the TFFs, SCGBs, HDACs and HATs were analysed using real-time PCR. Western blot analysis was performed to analyse the protein concentrations of the TFFs and SCGBs in secreted fractions of the sputum collection. Both the secreted and intracellular protein fractions collected from the sputum inductions for pre- and post-inflammation (SI-2, SI-3) samples of the N-A and A-BD groups were analysed using a proteomic method called iTRAQ. This allowed the comparison of the change in protein expression as a result of airway inflammation in each group. This technique was used as a discovery method to identify novel proteins that are modulated by induced acute airway inflammation. Any proteins of interest would then be further validated and used for future research. Inflammation was achieved in the SI-3 samples of the N-A group with a 21% unit increase in % neutrophils compared to SI-2 (p=0.01). The N-A group had a marked 5.5-fold decrease in HDAC1 gene expression in SI-3 compared to SI-2 (p=0.03). No differences were seen in any of the TFFs, SCGBs or any of the rest of the HDACs and HATs. Western blot data did not display any significant changes in the protein levels of the TFFs and SCGBs analysed. However, non-significant analysis of the data displayed increases in TFF1 and TFF3, and decreases in SCGB1A1 and SCGB3A2 for the majority of SI-3 samples compared to SI-2. The A-BD group also presented a marked increase in neutrophils in the SI-3 samples compared to SI-2 (27% unit increase, p=0.04). The A-BD group had a significant increase in TFF3 and SCGB1A1 gene expression concomitant with induced acute airway inflammation. A 7.3-fold increase in TFF3 (p=0.05) in SI-3 indicated that TFF3 is linked to inflammation in asthmatics. A 2.8-fold increase in SCGB1A1 (p=0.03) indicated that this gene is also up-regulated, suggesting that this SCGB is expressed to try to combat induced acute airway inflammation. No significant changes were seen in any of the other genes analysed. Western blot data did not display any significant changes in the protein levels of the TFFs and SCGBs analysed. However, non-significant analysis of the data displayed an increase in TFF1 and TFF3, and a decrease in SCGB1A1 and SCGB3A2 in SI-3, similar to that seen in the N-A group. The A-ST group was different from the A-BD group, characterised by the use of inhaled corticosteroid medication to treat asthma symptoms. Inhaled corticosteroids are known to treat asthma symptoms through the control of inflammation. Therefore, it was expected that corticosteroid medication would also control the expression of TFFs, SCGBs, HATs and HDACs. Gene expression results only identified a 7.6-fold decrease in HDAC2 expression in SI-3 (p=0.001), which is proposed to be due to the up-regulation of HDAC2 protein that is known to be a function of corticosteroid use. Western blot data did not display any significant changes in the protein levels of the TFFs and SCGBs analysed. The gene expression in SI-2 and SI-3 in each group was compared. When comparing the A-BD group to the N-A group, a 9-fold increase in TFF3 (p=0.008) and a 34-fold increase in SCGB1A1 (p=0.03) were seen in the SI-3 samples. Comparisons of the A-ST group to the N-A group had an increased expression in SI-2 samples for HDAC5 (3.6-fold, p=0.04), NCOA2 (8.5-fold, p=0.04), NCOA3 (17-fold, p=0.01), HAT-1 (36-fold, p=0.003) and CREBBP (13-fold, p=0.001). The SI-3 samples in the A-ST group compared to the N-A group had increased expression for HDAC1 (6.4-fold, p=0.04), HDAC5 (5.2-fold, p=0.008), NCOA2 (9.6-fold, p=0.03), NCOA3 (16-fold, p=0.06), HAT-1 (41-fold, p<0.001) and CREBBP (31-fold, p=0.001). Comparisons of the A-ST group to the A-BD group had SI-2 increases in HDAC1 (3.8-fold, p=0.03), NCOA3 (4.5-fold, p=0.03), HAT-1 (5.3-fold, p=0.01) and CREBBP (23-fold, p=0.001), while SI-3 comparisons saw a decrease in HDAC2 (41-fold, p=0.008) and increases in HAT-1 (4.3-fold, p=0.003) and CREBBP (40-fold, p=0.001). Results showed that TFF3 and SCGB1A1 expression is higher in asthmatics than non-asthmatics and that histone acetylation is more active in the A-ST group than either the N-A or A-BD group, which suggests that histone acetylation activity may be positively correlated with asthma severity. The iTRAQ proteomic analysis of the secreted protein samples identified the SCGB1A1 protein and found it to be decreased in both the N-A and A-BD groups post-inflammation, but significantly so only in the A-BD group. Although no significant results were obtained from the western blot data, both groups displayed a decrease in SCGB1A1 concentration in SI-3 samples, suggesting a correlation with the proteomic data. Only 31 peptides were identified from the secreted samples. The intracellular iTRAQ analysis successfully identified 664 peptides, eight of which had differential expression in association with induced acute airway inflammation. Significant increases were seen in the A-BD group in SI-3 compared to SI-2 than in the N-A group in chloride intracellular channel protein 1, keratin-19, eosinophil cationic protein, calnexin, peroxiredoxin-5, and ATP-synthase delta subunit, while decreases were seen in cystatin-A and mucin-5AC. The iTRAQ analysis was only a discovery measure and further validation must be performed. In summary, the expression of TFFs and SCGBs differed between non-asthmatics and asthmatics. It is clear that TFF3 is active in the airway inflammation associated with asthma as indicated by an increase associated with inflammation in the A-BD group compared to the N-A group. Results for HDAC and HAT genes showed high HAT expression in the A-ST group compared to the N-A and A-BD groups, suggesting that histone acetyltransferases may be responsible for the characteristic unregulated inflammatory symptoms of asthmatics taking corticosteroids. Interestingly, corticosteroid medication did not seem to silence the expression of the analysed HAT genes, which indicates that corticosteroids may not control inflammation by direct regulation of HATs, but instead by competition, most probably with HDAC2 protein. As a discovery tool, iTRAQ is a potent method to both identify and compare the concentration of proteins between samples. The method is a powerful first step into the identification of novel proteins that are regulated in response to different treatments.