953 resultados para Minimum SNPs


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Traffic generated semi and non volatile organic compounds (SVOCs and NVOCs) pose a serious threat to human and ecosystem health when washed off into receiving water bodies by stormwater. Climate change influenced rainfall characteristics makes the estimation of these pollutants in stormwater quite complex. The research study discussed in the paper developed a prediction framework for such pollutants under the dynamic influence of climate change on rainfall characteristics. It was established through principal component analysis (PCA) that the intensity and durations of low to moderate rain events induced by climate change mainly affect the wash-off of SVOCs and NVOCs from urban roads. The study outcomes were able to overcome the limitations of stringent laboratory preparation of calibration matrices by extracting uncorrelated underlying factors in the data matrices through systematic application of PCA and factor analysis (FA). Based on the initial findings from PCA and FA, the framework incorporated orthogonal rotatable central composite experimental design to set up calibration matrices and partial least square regression to identify significant variables in predicting the target SVOCs and NVOCs in four particulate fractions ranging from >300-1 μm and one dissolved fraction of <1 μm. For the particulate fractions range >300-1 μm, similar distributions of predicted and observed concentrations of the target compounds from minimum to 75th percentile were achieved. The inter-event coefficient of variations for particulate fractions of >300-1 μm were 5% to 25%. The limited solubility of the target compounds in stormwater restricted the predictive capacity of the proposed method for the dissolved fraction of <1 μm.

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Contact lenses are a common method for the correction of refractive errors of the eye. While there have been significant advancements in contact lens designs and materials over the past few decades, the lenses still represent a foreign object in the ocular environment and may lead to physiological as well as mechanical effects on the eye. When contact lenses are placed in the eye, the ocular anatomical structures behind and in front of the lenses are directly affected. This thesis presents a series of experiments that investigate the mechanical and physiological effects of the short-term use of contact lenses on anterior and posterior corneal topography, corneal thickness, the eyelids, tarsal conjunctiva and tear film surface quality. The experimental paradigm used in these studies was a repeated measures, cross-over study design where subjects wore various types of contact lenses on different days and the lenses were varied in one or more key parameters (e.g. material or design). Both, old and newer lens materials were investigated, soft and rigid lenses were used, high and low oxygen permeability materials were tested, toric and spherical lens designs were examined, high and low powers and small and large diameter lenses were used in the studies. To establish the natural variability in the ocular measurements used in the studies, each experiment also contained at least one “baseline” day where an identical measurement protocol was followed, with no contact lenses worn. In this way, changes associated with contact lens wear were considered in relation to those changes that occurred naturally during the 8 hour period of the experiment. In the first study, the regional distribution and magnitude of change in corneal thickness and topography was investigated in the anterior and posterior cornea after short-term use of soft contact lenses in 12 young adults using the Pentacam. Four different types of contact lenses (Silicone hydrogel/ Spherical/–3D, Silicone Hydrogel/Spherical/–7D, Silicone Hydrogel/Toric/–3D and HEMA/Toric/–3D) of different materials, designs and powers were worn for 8 hours each, on 4 different days. The natural diurnal changes in corneal thickness and curvature were measured on two separate days before any contact lens wear. Significant diurnal changes in corneal thickness and curvature within the duration of the study were observed and these were taken into consideration for calculating the contact lens induced corneal changes. Corneal thickness changed significantly with lens wear and the greatest corneal swelling was seen with the hydrogel (HEMA) toric lens with a noticeable regional swelling of the cornea beneath the stabilization zones, the thickest regions of the lenses. The anterior corneal surface generally showed a slight flattening with lens wear. All contact lenses resulted in central posterior corneal steepening, which correlated with the relative degree of corneal swelling. The corneal swelling induced by the silicone hydrogel contact lenses was typically less than the natural diurnal thinning of the cornea over this same period (i.e. net thinning). This highlights why it is important to consider the natural diurnal variations in corneal thickness observed from morning to afternoon to accurately interpret contact lens induced corneal swelling. In the second experiment, the relative influence of lenses of different rigidity (polymethyl methacrylate – PMMA, rigid gas permeable – RGP and silicone hydrogel – SiHy) and diameters (9.5, 10.5 and 14.0) on corneal thickness, topography, refractive power and wavefront error were investigated. Four different types of contact lenses (PMMA/9.5, RGP/9.5, RGP/10.5, SiHy/14.0), were worn by 14 young healthy adults for a period of 8 hours on 4 different days. There was a clear association between fluorescein fitting pattern characteristics (i.e. regions of minimum clearance in the fluorescein pattern) and the resulting corneal shape changes. PMMA lenses resulted in significant corneal swelling (more in the centre than periphery) along with anterior corneal steepening and posterior flattening. RGP lenses, on the other hand, caused less corneal swelling (more in the periphery than centre) along with opposite effects on corneal curvature, anterior corneal flattening and posterior steepening. RGP lenses also resulted in a clinically and statistically significant decrease in corneal refractive power (ranging from 0.99 to 0.01 D), large enough to affect vision and require adjustment in the lens power. Wavefront analysis also showed a significant increase in higher order aberrations after PMMA lens wear, which may partly explain previous reports of "spectacle blur" following PMMA lens wear. We further explored corneal curvature, thickness and refractive changes with back surface toric and spherical RGP lenses in a group of 6 subjects with toric corneas. The lenses were worn for 8 hours and measurements were taken before and after lens wear, as in previous experiments. Both lens types caused anterior corneal flattening and a decrease in corneal refractive power but the changes were greater with the spherical lens. The spherical lens also caused a significant decrease in WTR astigmatism (WRT astigmatism defined as major axis within 30 degrees of horizontal). Both the lenses caused slight posterior corneal steepening and corneal swelling, with a greater effect in the periphery compared to the central cornea. Eyelid position, lid-wiper and tarsal conjunctival staining were also measured in Experiment 2 after short-term use of the rigid and SiHy contact lenses. Digital photos of the external eyes were captured for lid position analysis. The lid-wiper region of the marginal conjunctiva was stained using fluorescein and lissamine green dyes and digital photos were graded by an independent masked observer. A grading scale was developed in order to describe the tarsal conjunctival staining. A significant decrease in the palpebral aperture height (blepharoptosis) was found after wearing of PMMA/9.5 and RGP/10.5 lenses. All three rigid contact lenses caused a significant increase in lid-wiper and tarsal staining after 8 hours of lens wear. There was also a significant diurnal increase in tarsal staining, even without contact lens wear. These findings highlight the need for better contact lens edge design to minimise the interactions between the lid and contact lens edge during blinking and more lubricious contact lens surfaces to reduce ocular surface micro-trauma due to friction and for. Tear film surface quality (TFSQ) was measured using a high-speed videokeratoscopy technique in Experiment 2. TFSQ was worse with all the lenses compared to baseline (PMMA/9.5, RGP/9.5, RGP/10.5, and SiHy/14) in the afternoon (after 8 hours) during normal and suppressed blinking conditions. The reduction in TFSQ was similar with all the contact lenses used, irrespective of their material and diameter. An unusual pattern of change in TFSQ in suppressed blinking conditions was also found. The TFSQ with contact lens was found to decrease until a certain time after which it improved to a value even better than the bare eye. This is likely to be due to the tear film drying completely over the surface of the contact lenses. The findings of this study also show that there is still a scope for improvement in contact lens materials in terms of better wettability and hydrophilicity in order to improve TFSQ and patient comfort. These experiments showed that a variety of changes can occur in the anterior eye as a result of the short-term use of a range of commonly used contact lens types. The greatest corneal changes occurred with lenses manufactured from older HEMA and PMMA lens materials, whereas modern SiHy and rigid gas permeable materials caused more subtle changes in corneal shape and thickness. All lenses caused signs of micro-trauma to the eyelid wiper and palpebral conjunctiva, although rigid lenses appeared to cause more significant changes. Tear film surface quality was also significantly reduced with all types of contact lenses. These short-term changes in the anterior eye are potential markers for further long term changes and the relative differences between lens types that we have identified provide an indication of areas of contact lens design and manufacture that warrant further development.

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In the asymmetric unit of the title co-crystal, C12H14N4O2S . C7H5NO4 there are two independent but conformationally similar heterodimers, which are formed through intermolecular N-H...O(carboxy) and carboxyl O-H...N hydrogen-bond pairs, giving a cyclic motif [graph set R2/2(8)]. The dihedral angles between the rings in the sulfonamide molecules are 78.77(8) and 82.33(9)deg. while the dihedral angles between the ring and the CO2H group in the acids are 2.19(9) and 7.02(10)deg. A two-dimensional structure parallel to the ab plane is generated from the heterodimer units through hydrogen-bonding associations between NH2 and sulfone groups. Between neighbouring two-dimensional arrays there are two types of aromatic pi-pi stacking interactions involving either one of the pyrimidine rings and a 4-nitrobenzoic acid molecule [minimum ring centroid separation = 3.5886(9)A] or two acid molecules [minimum ring centroid separation = 3.7236(10)A].

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A practical approach for identifying solution robustness is proposed for situations where parameters are uncertain. The approach is based upon the interpretation of a probability density function (pdf) and the definition of three parameters that describe how significant changes in the performance of a solution are deemed to be. The pdf is constructed by interpreting the results of simulations. A minimum number of simulations are achieved by updating the mean, variance, skewness and kurtosis of the sample using computationally efficient recursive equations. When these criterions have converged then no further simulations are needed. A case study involving several no-intermediate storage flow shop scheduling problems demonstrates the effectiveness of the approach.

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Adult education plays an important role in global economic development and features prominently in debates about changing requirements of post-industrial knowledge societies. This dominant technical-instrumental understanding of adult education in public discourse masks the transformative function of certain types of adult education - that is, the possibilities of adult education to improve social justice issues such as workers’ rights, human rights, civic participation in governance and socially just development. Given the increasing social stratification between and within the North and South in the global era, the potential of adult education to effect social change has been rediscovered by organisations within global civil society, namely international non-governmental organisations (INGOs). The broad objective of this research was to carry out an in-depth qualitative case study of a human rights advocacy program provided by a Northern INGO predominantly operating within the global South. The study analyses how participants see this program in terms of its potential to contribute to progressive social change in their home communities across the Asia-Pacific region. The following questions guided the study: 1. To what extent does this adult education program challenge existing systems of domination and marginalisation? 2. How did completion of the program affect participants’ views of their abilities to facilitate social action within their communities? Data sources for this research were interviews with 19 participants and staff and questionnaires from 28 participants of the program from a variety of countries in the Asia-pacific region. The gap in the literature that this study addressed is that existing empirical research sidelines the analysis of the globalisation, adult education, and social change nexus from a perspective that takes the marginalised other seriously, tending instead to mirror the material subjugation of the South in discursive practices. Social change is highly context-specific and strategies to advance it depend on the way in which people understand their reality and are affected by adverse social conditions. The present study employed a postcolonial framework that provided a holistic approach to analysing adult education for social change inclusive of material, political, and social conditions and the interplay between these from the local to the global level. The program convincingly exemplified an example of adult education for counter-hegemonic resistance against the dominant neoliberal discourse. It achieved this by enabling participants, based on Freirian pedagogical principles, to locate the problem of social change and frame their strategies to address it within mutually constitutive local and global developments and the discourses that describe them. It provided the underpinning knowledge and skills for effective advocacy and created opportunities to build networks between various stakeholders. At minimum, most advocates accord their participation in the program a supporting role in enhancing their ability to examine causes for social injustices and ways to address these. Some advocates even regarded their program participation as fundamental in understanding these issues. Almost all participants reported an increased skill-set that enabled them to become more effective advocates.

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The electrical performance of indium tin oxide (ITO) coated glass was improved by including a controlled layer of carbon nanotubes directly on top of the ITO film. Multi-wall carbon nanotubes (MWCNTs) were synthesized by chemical vapor deposition, using ultra-thin Fe layers as catalyst. The process parameters (temperature, gas flow and duration) were carefully refined to obtain the appropriate size and density of MWCNTs with a minimum decrease of the light harvesting in the cell. When used as anodes for organic solar cells based on poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM), the MWCNT-enhanced electrodes are found to improve the charge carrier extraction from the photoactive blend, thanks to the additional percolation paths provided by the CNTs. The work function of as-modified ITO surfaces was measured by the Kelvin probe method to be 4.95 eV, resulting in an improved matching to the highest occupied molecular orbital level of the P3HT. This is in turn expected to increase the hole transport and collection at the anode, contributing to the significant increase of current density and open circuit voltage observed in test cells created with such MWCNT-enhanced electrodes.

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In the structure of the title salt 2C7H10N+.C8H2Cl2O4(2-) .H2O the two benzylaminium anions have different conformations, one being essentially planar the other having the side-chain rotated out of the benzene plane (minimum ring to side-chain C-C-C-N torsion angles = -3.6(6) and 50.1(5)\%, respectively). In the 4,5-dichlorophthalate dianion the carboxyl groups make ihedral angles of 23.0(2) and 76.5(2)\% with the benzene ring. Aminium N-H...O and water O-H...O hydrogen-bonding associations with carboxyl O-atom acceptors give a two-dimensional duplex sheet structure which extends along the (011) plane. Weak pi-pi interactions are also present between the benzene ring and one of the cation rings [minimum ring centroid separation = 3.749(3)Ang.

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This article reviews the literature on the outcome of flapless surgery for dental implants in the posterior maxilla. The literature search was carried out in using the keywords: flapless, dental implants and maxilla. A hand search and Medline search were carried out on studies published between 1971 and 2011. The authors included research involving a minimum of 15 dental implants with a followup period of 1 year, an outcome measurement of implant survival, but excluded studies involving multiple simultaneous interventions, and studies with missing data. The Cochrane approach for cohort studies and Oxford Centre for Evidence- Based Medicine were applied. Of the 56 published papers selected, 14 papers on the flapless technique showed high overall implant survival rates. The prospective studies yielded 97.01% (95% CI: 90.72–99.0) while retrospective studies or case series illustrated 95.08% (95% CI: 91.0–97.93) survival. The average of intraoperative complications was 6.55% using the flapless procedure. The limited data obtained showed that flapless surgery in posterior maxilla areas could be a viable and predictable treatment method for implant placement. Flapless surgery tends to be more applicable in this area of the mouth. Further long-term clinical controlled studies are needed.

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The human Ureaplasma species are the most frequently isolated bacteria from the upper genital tract of pregnant women and can cause clinically asymptomatic, intra-uterine infections, which are difficult to treat with antimicrobials. Ureaplasma infection of the upper genital tract during pregnancy has been associated with numerous adverse outcomes including preterm birth, chorioamnionitis and neonatal respiratory diseases. The mechanisms by which ureaplasmas are able to chronically colonise the amniotic fluid and avoid eradication by (i) the host immune response and (ii) maternally-administered antimicrobials, remain virtually unexplored. To address this gap within the literature, this study investigated potential mechanisms by which ureaplasmas are able to cause chronic, intra-amniotic infections in an established ovine model. In this PhD program of research the effectiveness of standard, maternal erythromycin for the treatment of chronic, intra-amniotic ureaplasma infections was evaluated. At 55 days of gestation pregnant ewes received an intra-amniotic injection of either: a clinical Ureaplasma parvum serovar 3 isolate that was sensitive to macrolide antibiotics (n = 16); or 10B medium (n = 16). At 100 days of gestation, ewes were then randomised to receive either maternal erythromycin treatment (30 mg/kg/day for four days) or no treatment. Ureaplasmas were isolated from amniotic fluid, chorioamnion, umbilical cord and fetal lung specimens, which were collected at the time of preterm delivery of the fetus (125 days of gestation). Surprisingly, the numbers of ureaplasmas colonising the amniotic fluid and fetal tissues were not different between experimentally-infected animals that received erythromycin treatment or infected animals that did not receive treatment (p > 0.05), nor were there any differences in fetal inflammation and histological chorioamnionitis between these groups (p > 0.05). These data demonstrate the inability of maternal erythromycin to eradicate intra-uterine ureaplasma infections. Erythromycin was detected in the amniotic fluid of animals that received antimicrobial treatment (but not in those that did not receive treatment) by liquid chromatography-mass spectrometry; however, the concentrations were below therapeutic levels (<10 – 76 ng/mL). These findings indicate that the ineffectiveness of standard, maternal erythromycin treatment of intra-amniotic ureaplasma infections may be due to the poor placental transfer of this drug. Subsequently, the phenotypic and genotypic characteristics of ureaplasmas isolated from the amniotic fluid and chorioamnion of pregnant sheep after chronic, intra-amniotic infection and low-level exposure to erythromycin were investigated. At 55 days of gestation twelve pregnant ewes received an intra-amniotic injection of a clinical U. parvum serovar 3 isolate, which was sensitive to macrolide antibiotics. At 100 days of gestation, ewes received standard maternal erythromycin treatment (30 mg/kg/day for four days, n = 6) or saline (n = 6). Preterm fetuses were surgically delivered at 125 days of gestation and ureaplasmas were cultured from the amniotic fluid and the chorioamnion. The minimum inhibitory concentrations (MICs) of erythromycin, azithromycin and roxithromycin were determined for cultured ureaplasma isolates, and antimicrobial susceptibilities were different between ureaplasmas isolated from the amniotic fluid (MIC range = 0.08 – 1.0 mg/L) and chorioamnion (MIC range = 0.06 – 5.33 mg/L). However, the increased resistance to macrolide antibiotics observed in chorioamnion ureaplasma isolates occurred independently of exposure to erythromycin in vivo. Remarkably, domain V of the 23S ribosomal RNA gene (which is the target site of macrolide antimicrobials) of chorioamnion ureaplasmas demonstrated significant variability (125 polymorphisms out of 422 sequenced nucleotides, 29.6%) when compared to the amniotic fluid ureaplasma isolates and the inoculum strain. This sequence variability did not occur as a consequence of exposure to erythromycin, as the nucleotide substitutions were identical between chorioamnion ureaplasmas isolated from different animals, including those that did not receive erythromycin treatment. We propose that these mosaic-like 23S ribosomal RNA gene sequences may represent gene fragments transferred via horizontal gene transfer. The significant differences observed in (i) susceptibility to macrolide antimicrobials and (ii) 23S ribosomal RNA sequences of ureaplasmas isolated from the amniotic fluid and chorioamnion suggests that the anatomical site from which they were isolated may exert selective pressures that alter the socio-microbiological structure of the bacterial population, by selecting for genetic changes and altered antimicrobial susceptibility profiles. The final experiment for this PhD examined antigenic size variation of the multiple banded antigen (MBA, a surface-exposed lipoprotein and predicted ureaplasmal virulence factor) in chronic, intra-amniotic ureaplasma infections. Previously defined ‘virulent-derived’ and ‘avirulent-derived’ clonal U. parvum serovar 6 isolates (each expressing a single MBA protein) were injected into the amniotic fluid of pregnant ewes (n = 20) at 55 days of gestation, and amniotic fluid was collected by amniocentesis every two weeks until the time of near-term delivery of the fetus (at 140 days of gestation). Both the avirulent and virulent clonal ureaplasma strains generated MBA size variants (ranging in size from 32 – 170 kDa) within the amniotic fluid of pregnant ewes. The mean number of MBA size variants produced within the amniotic fluid was not different between the virulent (mean = 4.2 MBA variants) and avirulent (mean = 4.6 MBA variants) ureaplasma strains (p = 0.87). Intra-amniotic infection with the virulent strain was significantly associated with the presence of meconium-stained amniotic fluid (p = 0.01), which is an indicator of fetal distress in utero. However, the severity of histological chorioamnionitis was not different between the avirulent and virulent groups. We demonstrated that ureaplasmas were able to persist within the amniotic fluid of pregnant sheep for 85 days, despite the host mounting an innate and adaptive immune response. Pro-inflammatory cytokines (interleukin (IL)-1â, IL-6 and IL-8) were elevated within the chorioamnion tissue of pregnant sheep from both the avirulent and virulent treatment groups, and this was significantly associated with the production of anti-ureaplasma IgG antibodies within maternal sera (p < 0.05). These findings suggested that the inability of the host immune response to eradicate ureaplasmas from the amniotic cavity may be due to continual size variation of MBA surface-exposed epitopes. Taken together, these data confirm that ureaplasmas are able to cause long-term in utero infections in a sheep model, despite standard antimicrobial treatment and the development of a host immune response. The overall findings of this PhD project suggest that ureaplasmas are able to cause chronic, intra-amniotic infections due to (i) the limited placental transfer of erythromycin, which prevents the accumulation of therapeutic concentrations within the amniotic fluid; (ii) the ability of ureaplasmas to undergo rapid selection and genetic variation in vivo, resulting in ureaplasma isolates with variable MICs to macrolide antimicrobials colonising the amniotic fluid and chorioamnion; and (iii) antigenic size variation of the MBA, which may prevent eradication of ureaplasmas by the host immune response and account for differences in neonatal outcomes. The outcomes of this program of study have improved our understanding of the biology and pathogenesis of this highly adapted microorganism.

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Newly licensed drivers on a provisional or intermediate licence have the highest crash risk when compared with any other group of drivers. In comparison, learner drivers have the lowest crash risk. Graduated driver licensing is one countermeasure that has been demonstrated to effectively reduce the crashes of novice drivers. This thesis examined the graduated driver licensing systems in two Australian states in order to better understand the behaviour of learner drivers, provisional drivers and the supervisors of learner drivers. By doing this, the thesis investigated the personal, social and environmental influences on novice driver behaviour as well as providing effective baseline data against which to measure subsequent changes to the licensing systems. In the first study, conducted prior to the changes to the graduated driver licensing system introduced in mid-2007, drivers who had recently obtained their provisional licence in Queensland and New South Wales were interviewed by telephone regarding their experiences while driving on their learner licence. Of the 687 eligible people approached to participate at driver licensing centres, 392 completed the study representing a response rate of 57.1 per cent. At the time the data was collected, New South Wales represented a more extensive graduated driver licensing system when compared with Queensland. The results suggested that requiring learners to complete a mandated number of hours of supervised practice impacts on the amount of hours that learners report completing. While most learners from New South Wales reported meeting the requirement to complete 50 hours of practice, it appears that many stopped practising soon after this goal was achieved. In contrast, learners from Queensland, who were not required to complete a specific number of hours at the time of the survey, tended to fall into three groups. The first group appeared to complete the minimum number of hours required to pass the test (less than 26 hours), the second group completed 26 to 50 hours of supervised practice while the third group completed significantly more practice than the first two groups (over 100 hours of supervised practice). Learner drivers in both states reported generally complying with the road laws and were unlikely to report that they had been caught breaking the road rules. They also indicated that they planned to obey the road laws once they obtained their provisional licence. However, they were less likely to intend to comply with recommended actions to reduce crash risk such as limiting their driving at night. This study also identified that there were relatively low levels of unaccompanied driving (approximately 15 per cent of the sample), very few driving offences committed (five per cent of the sample) and that learner drivers tended to use a mix of private and professional supervisors (although the majority of practice is undertaken with private supervisors). Consistent with the international literature, this study identified that very few learner drivers had experienced a crash (six per cent) while on their learner licence. The second study was also conducted prior to changes to the graduated driver licensing system and involved follow up interviews with the participants of the first study after they had approximately 21 months driving experience on their provisional licence. Of the 392 participants that completed the first study, 233 participants completed the second interview (representing a response rate of 59.4 per cent). As with the first study, at the time the data was collected, New South Wales had a more extensive graduated driver licensing system than Queensland. For instance, novice drivers from New South Wales were required to progress through two provisional licence phases (P1 and P2) while there was only one provisional licence phase in Queensland. Among the participants in this second study, almost all provisional drivers (97.9 per cent) owned or had access to a vehicle for regular driving. They reported that they were unlikely to break road rules, such as driving after a couple of drinks, but were also unlikely to comply with recommended actions, such as limiting their driving at night. When their provisional driving behaviour was compared to the stated intentions from the first study, the results suggested that their intentions were not a strong predictor of their subsequent behaviour. Their perception of risk associated with driving declined from when they first obtained their learner licence to when they had acquired provisional driving experience. Just over 25 per cent of participants in study two reported that they had been caught committing driving offences while on their provisional licence. Nearly one-third of participants had crashed while driving on a provisional licence, although few of these crashes resulted in injuries or hospitalisations. To complement the first two studies, the third study examined the experiences of supervisors of learner drivers, as well as their perceptions of their learner’s experiences. This study was undertaken after the introduction of the new graduated driver licensing systems in Queensland and New South Wales in mid- 2007, providing insights into the impacts of these changes from the perspective of supervisors. The third study involved an internet survey of 552 supervisors of learner drivers. Within the sample, approximately 50 per cent of participants supervised their own child. Other supervisors of the learner drivers included other parents or stepparents, professional driving instructors and siblings. For two-thirds of the sample, this was the first learner driver that they had supervised. Participants had provided an average of 54.82 hours (sd = 67.19) of supervision. Seventy-three per cent of participants indicated that their learners’ logbooks were accurate or very accurate in most cases, although parents were more likely than non-parents to report that their learners’ logbook was accurate (F (1,546) = 7.74, p = .006). There was no difference between parents and non-parents regarding whether they believed the log book system was effective (F (1,546) = .01, p = .913). The majority of the sample reported that their learner driver had had some professional driving lessons. Notwithstanding this, a significant proportion (72.5 per cent) believed that parents should be either very involved or involved in teaching their child to drive, with parents being more likely than non-parents to hold this belief. In the post mid-2007 graduated driver licensing system, Queensland learner drivers are able to record three hours of supervised practice in their log book for every hour that is completed with a professional driving instructor, up to a total of ten hours. Despite this, there was no difference identified between Queensland and New South Wales participants regarding the amount of time that they reported their learners spent with professional driving instructors (X2(1) = 2.56, p = .110). Supervisors from New South Wales were more likely to ensure that their learner driver complied with the road laws. Additionally, with the exception of drug driving laws, New South Wales supervisors believed it was more important to teach safety-related behaviours such as remaining within the speed limit, car control and hazard perception than those from Queensland. This may be indicative of more intensive road safety educational efforts in New South Wales or the longer time that graduated driver licensing has operated in that jurisdiction. However, other factors may have contributed to these findings and further research is required to explore the issue. In addition, supervisors reported that their learner driver was involved in very few crashes (3.4 per cent) and offences (2.7 per cent). This relatively low reported crash rate is similar to that identified in the first study. Most of the graduated driver licensing research to date has been applied in nature and lacked a strong theoretical foundation. These studies used Akers’ social learning theory to explore the self-reported behaviour of novice drivers and their supervisors. This theory was selected as it has previously been found to provide a relatively comprehensive framework for explaining a range of driver behaviours including novice driver behaviour. Sensation seeking was also used in the first two studies to complement the non-social rewards component of Akers’ social learning theory. This program of research identified that both Akers’ social learning theory and sensation seeking were useful in predicting the behaviour of learner and provisional drivers over and above socio-demographic factors. Within the first study, Akers’ social learning theory accounted for an additional 22 per cent of the variance in learner driver compliance with the law, over and above a range of socio-demographic factors such as age, gender and income. The two constructs within Akers’ theory which were significant predictors of learner driver compliance were the behavioural dimension of differential association relating to friends, and anticipated rewards. Sensation seeking predicted an additional six per cent of the variance in learner driver compliance with the law. When considering a learner driver’s intention to comply with the law while driving on a provisional licence, Akers’ social learning theory accounted for an additional 10 per cent of the variance above socio-demographic factors with anticipated rewards being a significant predictor. Sensation seeking predicted an additional four per cent of the variance. The results suggest that the more rewards individuals anticipate for complying with the law, the more likely they are to obey the road rules. Further research is needed to identify which specific rewards are most likely to encourage novice drivers’ compliance with the law. In the second study, Akers’ social learning theory predicted an additional 40 per cent of the variance in self-reported compliance with road rules over and above socio-demographic factors while sensation seeking accounted for an additional five per cent of the variance. A number of Aker’s social learning theory constructs significantly predicted provisional driver compliance with the law, including the behavioural dimension of differential association for friends, the normative dimension of differential association, personal attitudes and anticipated punishments. The consistent prediction of additional variance by sensation seeking over and above the variables within Akers’ social learning theory in both studies one and two suggests that sensation seeking is not fully captured within the non social rewards dimension of Akers’ social learning theory, at least for novice drivers. It appears that novice drivers are strongly influenced by the desire to engage in new and intense experiences. While socio-demographic factors and the perception of risk associated with driving had an important role in predicting the behaviour of the supervisors of learner drivers, Akers’ social learning theory provided further levels of prediction over and above these factors. The Akers’ social learning theory variables predicted an additional 14 per cent of the variance in the extent to which supervisors ensured that their learners complied with the law and an additional eight per cent of the variance in the supervisors’ provision of a range of practice experiences. The normative dimension of differential association, personal attitudes towards the use of professional driving instructors and anticipated rewards were significant predictors for supervisors ensuring that their learner complied with the road laws, while the normative dimension was important for range of practice. This suggests that supervisors who engage with other supervisors who ensure their learner complies with the road laws and provide a range of practice to their own learners are more likely to also engage in these behaviours. Within this program of research, there were several limitations including the method of recruitment of participants within the first study, the lower participation rate in the second study, an inability to calculate a response rate for study three and the use of self-report data for all three studies. Within the first study, participants were only recruited from larger driver licensing centres to ensure that there was a sufficient throughput of drivers to approach. This may have biased the results due to the possible differences in learners that obtain their licences in locations with smaller licensing centres. Only 59.4 per cent of the sample in the first study completed the second study. This may be a limitation if there was a common reason why those not participating were unable to complete the interview leading to a systematic impact on the results. The third study used a combination of a convenience and snowball sampling which meant that it was not possible to calculate a response rate. All three studies used self-report data which, in many cases, is considered a limitation. However, self-report data may be the only method that can be used to obtain some information. This program of research has a number of implications for countermeasures in both the learner licence phase and the provisional licence phase. During the learner phase, licensing authorities need to carefully consider the number of hours that they mandate learner drivers must complete before they obtain their provisional driving licence. If they mandate an insufficient number of hours, there may be inadvertent negative effects as a result of setting too low a limit. This research suggests that logbooks may be a useful tool for learners and their supervisors in recording and structuring their supervised practice. However, it would appear that the usage rates for logbooks will remain low if they remain voluntary. One strategy for achieving larger amounts of supervised practice is for learner drivers and their supervisors to make supervised practice part of their everyday activities. As well as assisting the learner driver to accumulate the required number of hours of supervised practice, it would ensure that they gain experience in the types of environments that they will probably encounter when driving unaccompanied in the future, such as to and from education or work commitments. There is also a need for policy processes to ensure that parents and professional driving instructors communicate effectively regarding the learner driver’s progress. This is required as most learners spend at least some time with a professional instructor despite receiving significant amounts of practice with a private supervisor. However, many supervisors did not discuss their learner’s progress with the driving instructor. During the provisional phase, there is a need to strengthen countermeasures to address the high crash risk of these drivers. Although many of these crashes are minor, most involve at least one other vehicle. Therefore, there are social and economic benefits to reducing these crashes. If the new, post-2007 graduated driver licensing systems do not significantly reduce crash risk, there may be a need to introduce further provisional licence restrictions such as separate night driving and peer passenger restrictions (as opposed to the hybrid version of these two restrictions operating in both Queensland and New South Wales). Provisional drivers appear to be more likely to obey some provisional licence laws, such as lower blood alcohol content limits, than others such as speed limits. Therefore, there may be a need to introduce countermeasures to encourage provisional drivers to comply with specific restrictions. When combined, these studies provided significant information regarding graduated driver licensing programs. This program of research has investigated graduated driver licensing utilising a cross-sectional and longitudinal design in order to develop our understanding of the experiences of novice drivers that progress through the system in order to help reduce crash risk once novice drivers commence driving by themselves.

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In this conceptual article, we extend earlier work on Open Innovation and Absorptive Capacity. We suggest that the literature on Absorptive Capacity does not place sufficient emphasis on distributed knowledge and learning or on the application of innovative knowledge. To accomplish physical transformations, organisations need specific Innovative Capacities that extend beyond knowledge management. Accessive Capacity is the ability to collect, sort and analyse knowledge from both internal and external sources. Adaptive Capacity is needed to ensure that new pieces of equipment are suitable for the organisation's own purposes even though they may have been originally developed for other uses. Integrative Capacity makes it possible for a new or modified piece of equipment to be fitted into an existing production process with a minimum of inessential and expensive adjustment elsewhere in the process. These Innovative Capacities are controlled and coordinated by Innovative Management Capacity, a higher-order dynamic capability.

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The Kyoto Protocol recognises trees as a sink of carbon and a valid means to offset greenhouse gas emissions and meet internationally agreed emissions targets. This study details biological carbon sequestration rates for common plantation species Araucaria cunninghamii (hoop pine), Eucalyptus cloeziana, Eucalyptus argophloia, Pinus elliottii and Pinus caribaea var hondurensis and individual land areas required in north-eastern Australia to offset greenhouse gas emissions of 1000tCO 2e. The 3PG simulation model was used to predict above and below-ground estimates of biomass carbon for a range of soil productivity conditions for six representative locations in agricultural regions of north-eastern Australia. The total area required to offset 1000tCO 2e ranges from 1ha of E. cloeziana under high productivity conditions in coastal North Queensland to 45ha of hoop pine in low productivity conditions of inland Central Queensland. These areas must remain planted for a minimum of 30years to meet the offset of 1000tCO 2e.

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Software as a Service (SaaS) is gaining more and more attention from software users and providers recently. This has raised many new challenges to SaaS providers in providing better SaaSes that suit everyone needs at minimum costs. One of the emerging approaches in tackling this challenge is by delivering the SaaS as a composite SaaS. Delivering it in such an approach has a number of benefits, including flexible offering of the SaaS functions and decreased cost of subscription for users. However, this approach also introduces new problems for SaaS resource management in a Cloud data centre. We present the problem of composite SaaS resource management in Cloud data centre, specifically on its initial placement and resource optimization problems aiming at improving the SaaS performance based on its execution time as well as minimizing the resource usage. Our approach differs from existing literature because it addresses the problems resulting from composite SaaS characteristics, where we focus on the SaaS requirements, constraints and interdependencies. The problems are tackled using evolutionary algorithms. Experimental results demonstrate the efficiency and the scalability of the proposed algorithms.

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The development of the Learning and Teaching Academic Standards Statement for Architecture (the Statement) centred on requirements for the Master of Architecture and proceeded alongside similar developments in the building and construction discipline under the guidance and support of the Australian Deans of Built Environment and Design (ADBED). Through their representation of Australian architecture programs, ADBED have provided high-level leadership for the Learning and Teaching Academic Standards Project in Architecture (LTAS Architecture). The threshold learning outcomes (TLOs), the description of the nature and extent of the discipline, and accompanying notes were developed through wide consultation with the discipline and profession nationally. They have been considered and debated by ADBED on a number of occasions and have, in their fi nal form, been strongly endorsed by the Deans. ADBED formed the core of the Architecture Reference Group (chaired by an ADBED member) that drew together representatives of every peak organisation for the profession and discipline in Australia. The views of the architectural education community and profession have been provided both through individual submissions and the voices of a number of peak bodies. Over two hundred individuals from the practising profession, the academic workforce and the student cohort have worked together to build consensus about the capabilities expected of a graduate of an Australian Master of Architecture degree. It was critical from the outset that the Statement should embrace the wisdom of the greater ‘tribe’, should ensure that graduates of the Australian Master of Architecture were eligible for professional registration and, at the same time, should allow for scope and diversity in the shape of Australian architectural education. A consultation strategy adopted by the Discipline Scholar involved meetings and workshops in Perth, Melbourne, Sydney, Canberra and Brisbane. Stakeholders from all jurisdictions and most universities participated in the early phases of consultation through a series of workshops that concluded late in October 2010. The Draft Architecture Standards Statement was formed from these early meetings and consultation in respect of that document continued through early 2011. This publication represents the outcomes of work to establish an agreed standards statement for the Master of Architecture. Significant further work remains to ensure the alignment of professional accreditation and recognition procedures with emerging regulatory frameworks cascading from the establishment of the Tertiary Education Quality and Standards Agency (TEQSA). The Australian architecture community hopes that mechanisms can be found to integrate TEQSA’s quality assurance purpose with well-established and understood systems of professional accreditation to ensure the good standing of Australian architectural education into the future. The work to build renewed and integrated quality assurance processes and to foster the interests of this project will continue, for at least the next eighteen months, under the auspices of Australian Learning and Teaching Council (ALTC)-funded Architecture Discipline Network (ADN), led by ADBED and Queensland University of Technology. The Discipline Scholar gratefully acknowledges the generous contributions given by those in stakeholder communities to the formulation of the Statement. Professional and academic colleagues have travelled and gathered to shape the Standards Statement. Debate has been vigorous and spirited and the Statement is rich with the purpose, critical thinking and good judgement of the Australian architectural education community. The commitments made to the processes that have produced this Statement reflect a deep and abiding interest by the constituency in architectural education. This commitment bodes well for the vibrancy and productivity of the emergent Architecture Discipline Network (ADN). Endorsement, in writing, was received from the Australian Institute of Architects National Education Committee (AIA NEC): The National Education Committee (NEC) of the Australian Institute of Architects thank you for your work thus far in developing the Learning and Teaching Academic Standards for Architecture In particular, we acknowledge your close consultation with the NEC on the project along with a comprehensive cross-section of the professional and academic communities in architecture. The TLOs with the nuanced levels of capacities – to identify, develop, explain, demonstrate etc – are described at an appropriate level to be understood as minimum expectations for a Master of Architecture graduate. The Architects Accreditation Council of Australia (AACA) has noted: There is a clear correlation between the current processes for accreditation and what may be the procedures in the future following the current review. The requirement of the outcomes as outlined in the draft paper to demonstrate capability is an appropriate way of expressing the measure of whether the learning outcomes have been achieved. The measure of capability as described in the outcome statements is enhanced with explanatory descriptions in the accompanying notes.

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Appearance-based localization is increasingly used for loop closure detection in metric SLAM systems. Since it relies only upon the appearance-based similarity between images from two locations, it can perform loop closure regardless of accumulated metric error. However, the computation time and memory requirements of current appearance-based methods scale linearly not only with the size of the environment but also with the operation time of the platform. These properties impose severe restrictions on longterm autonomy for mobile robots, as loop closure performance will inevitably degrade with increased operation time. We present a set of improvements to the appearance-based SLAM algorithm CAT-SLAM to constrain computation scaling and memory usage with minimal degradation in performance over time. The appearance-based comparison stage is accelerated by exploiting properties of the particle observation update, and nodes in the continuous trajectory map are removed according to minimal information loss criteria. We demonstrate constant time and space loop closure detection in a large urban environment with recall performance exceeding FAB-MAP by a factor of 3 at 100% precision, and investigate the minimum computational and memory requirements for maintaining mapping performance.