Exploring optimistic and pessimistic attributions in depression-specific mood

Cognitive theories of depression include maladaptive thinking styles as depressive vulnerabilities. The hopelessness theory of depression (Abramson, Metalsky, & Alloy, 1989) particularly implicates stable and global attributions for negative events as influences upon depression. Positive event attributions are considered less influential, yet they have shown equal predictiveness to negative event attributions for depression-specific mood. Previous research has provided equivocal results largely because of cross-sectional design and modest psychometric properties of the measures. The present research aimed to: create a new instrument to measure optimistic and pessimistic attributions; test the relatedness of attributions for positive and negative events; and, clarify relationships of the scales with optimism and mood. Three studies were undertaken, all of which used structural equation modeling. Two cross-sectional studies, using 342 and 332 community participants respectively, developed and validated the Questionnaire of Explanatory Style (QES). A final longitudinal study with 250 community participants tested the predictive validity of the QES. Overall, six scales were developed, three of which were optimistic and three of which were negative. The scales were acceptable to community samples and had adequate psychometric properties. The optimistic scales were attributions for positive events and the negative scales were attributions for negative events rather than pessimistic scales. Cross-sectional results indicated that only one of the negative scales weakly directly predicted depression-specific mood, but all predicted general psychological distress. By contrast, the optimistic scales were more directly predictive of depression-specific mood, particularly the Positive Disposition scale. Longitudinal results indicated that two of the optimistic scales were the most important QES predictors of depression-specific mood two months later. The optimistic scale Positive Disposition appears most central to the prediction of both concurrent and subsequent depression-specific mood. The scale content represents explanations for positive events that are internal and stable characteristics. These may be construed as personal competencies to bring about positive outcomes. This scale is closely allied to measures of optimism. Findings affirm the importance of optimistic attributions to the understanding of depression-specific mood and provide a productive focus for therapeutic intervention and future research.

Sustaining collaborations : creative research and cross-cultural engagement

Increasingly, the linear, instrumentalist and culturally hegemonic character of dominant sustainability discourse is under critique, with the term accruing new or expanded associations that challenge the its future-oriented, temporally stable, and ontologically determinate history. In Australia, these shifts take in a recognition that indigenous Australian understandings of and relationships with the environment profoundly challenge the generic claims of sustainability applied to both theory and practice. But how do these radically different and still marginal understandings actually enter into the process of producing sustainable designs on the world? This paper will report on the beginnings of a collaborative project that seeks to advance a proposal for an Aboriginal cultural precinct in the heart of Melbourne. This project's intention is to develop innovative methods for consultation and participation through collaborative creative research between Aboriginal artists and academic architects. The paper will discuss this method as a strategy for moving beyond traditional modes of cross-cultural engagement in the design and construction of sustainable cultural precincts.

Tradition in a free society : the fideism of Michael Polanyi and the rationalism of Karl Popper

Michael Polanyi and Karl Popper offer contrasting accounts of social tradition. Popper is steeped in the heritage of the Enlightenment, while Polanyi interweaves religious and diverse secular strands of thought. Explaining the liberal tradition, Polanyi features tacit knowledge of rules, standards, applications and interpretations being transmitted by “craftsmen” to “apprentices.” Each generation adopts the liberal tradition on “faith,” commits to creatively developing its art of knowledge-in-practice, and is drawn to the spiritual reality of ideal ends. Of particular interest to Popper is the rationality of social traditions. Likened by him to scientific theories, Popper’s traditions are criticizable and improvable, assisting agents to understand, and act in, the world as stable and predictable. Polanyi’s is the more informative rendering of tradition. Polanyi delves deeply into important areas where Popper only scratches their surface: the tacit dimension, transmission by way of apprenticeship, the meaning of tradition for those who participate in it, and the extent of its authority over them.

Highly selective and sensitive DNA assay based on electrocatalytic oxidation of ferrocene bearing zinc(II)-cyclen complexes with diethylamine

A highly selective and sensitive electrochemical biosensor has been developed that detects DNA hybridization by employing the electrocatalytic activity of ferrocene (Fc) bearing cyclen complexes (cyclen = 1,4,7,10-tetraazacyclododecane, Fc[Zn(cyclen)H2O]2(ClO4)4 (R1), Fc(cyclen)2 (R2), Fc[Zn(cyclen)H2O](ClO4)2 (R3), and Fc(cyclen) (R4)). A sandwich-type approach, which involves hybridization of a target probe hybridized with the preimmobilized thiolated capture probe attached to a gold electrode, is employed to fabricate a DNA duplex layer. Electrochemical signals are generated by voltammetric interrogation of a Fc bearing Zn−cyclen complexes that selectively and quantitatively binds to the duplex layers through strong chelation between the cyclen complexes and particular nucleobases within the DNA sequence. Chelate formation between R1 or R3 and thymine bases leads to the perturbation of base-pair (A−T) stacking in the duplex structure, which greatly diminishes the yield of DNA-mediated charge transport and displays a marked selectivity to the presence of the target DNA sequence. Coupling the redox chemistry of the surface-bound Fc bearing Zn−cyclen complex and dimethylamine provides an electrocatalytic pathway that increases sensitivity of the assay and allows the 100 fM target DNA sequence to be detected. Excellent selectivity against even single-base sequence mismatches is achieved, and the DNA sensor is stable and reusable.

A robust solution to the stereo-vision-based simultaneous localization and mapping problem with steady and moving landmarks

The problem of visual simultaneous localization and mapping (SLAM) is examined in this paper using recently developed ideas and algorithms from modern robust control and estimation theory. A nonlinear model for a stereo-vision-based sensor is derived that leads to nonlinear measurements of the landmark coordinates along with optical flow-based measurements of the relative robot-landmark velocity. Using a novel analytical measurement transformation, the nonlinear SLAM problem is converted into the linear domain and solved using a robust linear filter. Actually, the linear filter is guaranteed stable and the SLAM state estimation error is bounded within an ellipsoidal set. A mathematically rigorous stability proof is given that holds true even when the landmarks move in accordance with an unknown control input. No similar results are available for the commonly employed extended Kalman filter, which is known to exhibit divergence and inconsistency characteristics in practice. A number of illustrative examples are given using both simulated and real vision data that further validate the proposed method.

Corner inlet and Nooramunga habitat mapping project

Deakin University and the University of Tasmania were commissioned by Parks Victoria (PV) to create two updated habitat maps for areas within the Corner Inlet and Nooramunga Marine and Coastal Park and Ramsar area. The team obtained a ground-truth data set using in situ video and still photographs. This dataset was used to develop and assess predictive models of benthic marine habitat distributions incorporating data from both ALOS (Advanced Land Observation Satellite) imagery atmospherically corrected by CSIRO and LiDAR (Light Detection and Ranging) bathymetry. This report describes the results of the mapping effort as well as the methodology used to produce these habitat maps.

Overall accuracies of habitat classifications were good, returning overall accuracies >73 % and kappa values > 0.62 for both study localities. Habitats predicted with highest accuracies included Zosteraceae in Nooramunga (91 %), reef in Corner Inlet (80 %), and bare sediment (no-visible macrobiota/no-visible seagrass classes; both > 76 %). The majority of classification errors were due to the misclassification of areas of sparse seagrass as bare sediment. For the Corner Inlet study locality the no-visible macrobiota (10,698 ha), Posidonia (4,608 ha) and Zosteraceae (4,229 ha) habitat classes covered the most area. In Nooramunga no-visible seagrass (5,538 ha), Zosteraceae (4,060 ha) and wet saltmarsh (1,562 ha) habitat classes were most dominant.

In addition to the commissioned work preliminary change detection analyses were undertaken as part of this project. These analyses indicated shifts in habitat extents in both study localities since the late 1990s/2000. In particular, a post-classification analysis highlighted that there were considerable increases in seagrass habitat (primarily Zosteraceae) throughout the littoral zones and river/creek mouths of both study localities. Further, the numerous channel systems remained stable and were free of seagrass at both times. A substantial net loss of Posidonia in the Corner Inlet locality is likely but requires further investigation due to potential misclassifications between habitats in both the 1998 map (Roob et al. 1998) and the current mapping. While the unsupervised Independent Components Analysis (ICA) change detection technique indicated some changes in habitat extent and distribution, considerable areas of habitat change observed in the post-classification approach are questionable, and may reflect misclassifications rather than real change. A particular example of this is an apparent large decrease in Zosteraceae and increase in Posidonia being related to the classification of Posidonia beds as Zosteraceae in the 1998 mapping. Despite this, we believe that changes indicated by both the ICA and post-classification approaches have a high likelihood of being ‘actual’ change. A pattern of gains and losses of Zosteraceae in the region north of Stockyard channel is an example of this. Further analyses and refinements of approaches in change detection analyses such as would improve confidence in the location and extent of habitat changes over this time period.

This work has been successful in providing new baseline maps using a repeatable method meaning that any future changes in intertidal and shallow water marine habitats may be assessed in a consistent way with quantitative error assessments. In wider use, these maps should also allow improved conservation planning, advance fisheries and catchment management, and progress infrastructure planning to limit impacts on the Inlet environment.

Understanding in-vivo abrasion fatigue or common suture materials used in arthroscopic and open shoulder surgery

In orthopaedic surgery the reattachment of tendon to bone requires suture materials that have stable and durable properties to allow healing at the tendon-bone interface. Failure rates of this type of surgery can be as high as 25%. While the tissue suture interface is a weak link, proportions of these failures are caused by in-vivo abrasion of the suture with bone and suture anchor materials. Abrasion of the suture material results from the movement of the suture through the eyelet by the surgeon during surgery, or with limb movement after surgery as the suture is not rigidly restrained within the eyelet. During movement the suture is subjected to bending and frictional forces that can lead to fatigue induced failure. This paper investigates the mechanism of bending abrasion fatigue induced failure of number two grade braided sheath only and braided sheath/multifilament core sutures. Sutures were oscillated over a stainless steel wire at low frequency under load in a dry state to simulate the bending and frictional forces between suture and eyelet. Failure mechanism was determined by video microscopy of the suture during abrasion combined with optical microscopy analysis of partially and fully abraded sutures. Braided only structures had high friction loading on the small number of fibres at the abrasion interface. This caused rapid single fibre breakages that accumulate to cause suture failure. The addition of ultra-high molecular weight polyethylene core fibres to a braided suture distributed the applied load across multiple fibres at the abrasion interface. This improved abrasion resistance by 15-20 times that of braided sheath alone.

Cross-validation of the factorial structure of the Neighborhood Environment Walkability Scale (NEWS) and its abbreviated form (NEWS-A)

Background : The Neighborhood Environment Walkability Scale (NEWS) and its abbreviated form (NEWS-A) assess perceived environmental attributes believed to influence physical activity. A multilevel confirmatory factor analysis (MCFA) conducted on a sample from Seattle, WA showed that, at the respondent level, the factor-analyzable items of the NEWS and NEWS-A measured 11 and 10 constructs of perceived neighborhood environment, respectively. At the census blockgroup (used by the US Census Bureau as a subunit of census tracts) level, the MCFA yielded five factors for both NEWS and NEWS-A. The aim of this study was to cross-validate the individual- and blockgroup-level measurement models of the NEWS and NEWS-A in a geographical location and population different from those used in the original validation study.

Methods : A sample of 912 adults was recruited from 16 selected neighborhoods (116 census blockgroups) in the Baltimore, MD region. Neighborhoods were stratified according to their socio-economic status and transport-related walkability level measured using Geographic Information Systems. Participants self-completed the NEWS. MCFA was used to cross-validate the individual- and blockgroup-level measurement models of the NEWS and NEWS-A.

Results : The data provided sufficient support for the factorial validity of the original individual-level measurement models, which consisted of 11 (NEWS) and 10 (NEWS-A) correlated factors. The original blockgroup-level measurement model of the NEWS and NEWS-A showed poor fit to the data and required substantial modifications. These included the combining of aspects of building aesthetics with safety from crime into one factor; the separation of natural aesthetics and building aesthetics into two factors; and for the NEWS-A, the separation of presence of sidewalks/walking routes from other infrastructure for walking.

Conclusion : This study provided support for the generalizability of the individual-level measurement models of the NEWS and NEWS-A to different urban geographical locations in the USA. It is recommended that the NEWS and NEWS-A be scored according to their individual-level measurement models, which are relatively stable and correspond to constructs commonly used in the urban planning and transportation fields. However, prior to using these instruments in international and multi-cultural studies, further validation work across diverse non-English speaking countries and populations is needed.

Short- and long-term consequences of early developmental conditions : a case study on wild and domesticated zebra finches

Divergent selection pressures among populations can result not only in significant differentiation in morphology, physiology and behaviour, but also in how these traits are related to each other, thereby driving the processes of local adaptation and speciation. In the Australian zebra finch, we investigated whether domesticated stock, bred in captivity over tens of generations, differ in their response to a life-history manipulation, compared to birds taken directly from the wild. In a ‘common aviary’ experiment, we thereto experimentally manipulated the environmental conditions experienced by nestlings early in life by means of a brood size manipulation, and subsequently assessed its short- and long-term consequences on growth, ornamentation, immune function and reproduction. As expected, we found that early environmental conditions had a marked effect on both short- and long-term morphological and life-history traits in all birds. However, although there were pronounced differences between wild and domesticated birds with respect to the absolute expression of many of these traits, which are indicative of the different selection pressures wild and domesticated birds were exposed to in the recent past, manipulated rearing conditions affected morphology and ornamentation of wild and domesticated finches in a very similar way. This suggests that despite significant differentiation between wild and domesticated birds, selection has not altered the relationships among traits. Thus, life-history strategies and investment trade-offs may be relatively stable and not easily altered by selection. This is a reassuring finding in the light of the widespread use of domesticated birds in studies of life-history evolution and sexual selection, and suggests that adaptive explanations may be legitimate when referring to captive bird studies.

Detecting the impact of invasive species on native fauna: Cane toads (Bufo marinus), frillneck lizards (Chlamydosaurus kingii) and the importance of spatial replication

An understanding of which native species are severely impacted by an anthropogenic change (such as the arrival of an invasive species) and which are not is critical to prioritizing conservation efforts. However, it is difficult to detect such impacts if the native taxa exhibit strong stochastic variations in abundance; a ‘natural’ population decline might be wrongly interpreted as an impact of the invader. Frillneck lizards (Chlamydosaurus kingii) are large iconic Australian agamids, and have been reported to decline following the invasion of toxic cane toads. We monitored three populations of the species in the savanna woodland of tropical Australia over a 7-year period bracketing toad arrival. One population crashed, one remained stable and one increased. Hence, studies on any single population might have inferred that cane toads have negative, negligible or positive effects on frillneck lizards. With the benefit of spatial replication, and in combination with observations of prey choice by captive lizards, our data suggest that invasive cane toads have had little or no effect on frillneck abundance.

An organic ionic plastic crystal electrolyte for rate capability and stability of ambient temperature lithium batteries

Reliable, safe and high performance solid electrolytes are a critical step in the advancement of high energy density secondary batteries. In the present work we demonstrate a novel solid electrolyte based on the organic ionic plastic crystal (OIPC) triisobutyl(methyl)phosphonium bis(fluorosulfonyl)imide (P1444FSI). With the addition of 4 mol% LiFSI, the OIPC shows a high conductivity of 0.26 mS cm-1 at 22 °C. The ion transport mechanisms have been rationalized by compiling thermal phase behaviour and crystal structure information obtained by variable temperature synchrotron X-ray diffraction. With a large electrochemical window (ca. 6 V) and importantly, the formation of a stable and highly conductive solid electrolyte interphase (SEI), we were able to cycle lithium cells (LiLiFePO4) at 30 °C and 20 °C at rates of up to 1 C with good capacity retention. At the 0.1 C rate, about 160 mA h g-1 discharge capacity was achieved at 20 °C, which is the highest for OIPC based cells to date. It is anticipated that these small phosphonium cation and [FSI] anion based OIPCs will show increasing significance in the field of solid electrolytes.

Tristearin bilayers: structure of the aqueous interface and stability in the presence of surfactants

We report results of atomistic molecular dynamics simulations of an industrially-relevant, exemplar triacylglycerol (TAG), namely tristearin (TS), under aqueous conditions, at different temperatures and in the presence of an anionic surfactant, sodium dodecylbenzene sulphonate (SDBS). We predict the TS bilayers to be stable and in a gel phase at temperatures of 350 K and below. At 370 K the lipid bilayer was able to melt, but does not feature a stable liquid-crystalline phase bilayer at this elevated temperature. We also predict the structural characteristics of TS bilayers in the presence of SDBS molecules under aqueous conditions, where surfactant molecules are found to spontaneously insert into the TS bilayers. We model TS bilayers containing different amounts of SDBS, with the presence of SDBS imparting only a moderate effect on the structure of the system. Our study represents the first step in applying atomistic molecular dynamics simulations to the investigation of TAG-aqueous interfaces. Our results suggest that the CHARMM36 force-field appears suitable for the simulation of such systems, although the phase behaviour of the system may be shifted to lower temperatures than is the case for the actual system. Our findings provide a foundation for further simulation studies of the TS-aqueous interface.

Enhancing thermal stability and mechanical properties of lyotropic liquid crystals through incorporation of a polymerizable surfactant.

We present a facile method to prepare thermally stable and mechanically robust crosslinked lyotropic liquid crystals (LLCs) through incorporation of a polymerizable amphiphile into a binary LLC system comprising commercially available surfactant Brij 97 and water. Thermal stability and mechanical properties of the polymerized LLCs were significantly enhanced after polymerization of the incorporated polymerizable surfactant. The effect of incorporating a polymerizable amphiphile on the phase behavior of the LLC system was studied in detail. In situ photo-rheology was used to monitor the change in the mechanical properties of the LLCs, namely the storage modulus, loss modulus, and viscosity, upon polymerization. The retention of the LLC nanostructures was evaluated by small angle X-ray scattering (SAXS). The ability to control the thermal stability and mechanical strength of LLCs simply by adding a polymerizable amphiphile, without tedious organic synthesis or harsh polymerization conditions, could prove highly advantageous in the preparation of robust nanomaterials with well-defined periodic structures.

Balanced-budget consumption taxes and aggregate stability in a small open economy

In a small open economy facing a perfect world capital market, this paper shows that if the government follows a balanced-budget fiscal policy based on endogenous consumption tax rates, then the steady state is saddle-path stable and hence beliefs-driven aggregate instability can be ruled out. This result is in contrast to those obtained in some closed economy models, and it suggests that unrestricted world capital mobility can help stabilize the economy under the balanced-budget fiscal policy based on consumption taxation.

First report of a phytogeographically mixed (transitional) Middle-Late Permian fossil wood assemblage from the Hami area, northwest China, and implications for Permian phytogeographical, paleogeographical and paleoclimatic evolution in central Asia

A diverse and well-preserved fossil wood assemblage is described, for the first time, from the Middle Permian Taerlang Formation and the Upper Permian Quanzijie Formation in the vicinity of the Tianshan Town, Hami City of northwestern China. On the basis of wood microstructure, the fossil woods are classified into three genera and five species, including one new genus: Prototianshanoxylon gen. nov. and two new species: Prototianshanoxylon erdaogouense sp. nov., Prototianshanoxylon hamiense sp. nov. The new genus is characterized by window-like cross-field pitting and mixed tracheid radial wall pitting that suggest a transitional type between araucarioid-type and protopinoid-type pittings.Phytogeographically, the fossil wood assemblage is characterized by an admixture of elements of both temperate Angaran (represented by wood specimens with moderately to well defined growth rings in their secondary xylem) and tropical-subtropical north subregion of the Cathaysian floras (with wood specimens lacking well-defined growth rings). Such a phytogeographically mixed fossil wood assemblage is interpreted to represent a transitional and complex climate condition between a cool temperate and tropical to subtropical zones, showing both seasonal variation and unstable climate conditions. Previously, similarly mixed floras have already been found to exist widely in northern China ranging in age from Early to Late Permian, but the mechanisms thought to be responsible for their formation were varied and remain controversial. In this study, the formation of these mixed Permian floras of North China is linked to the closure of the Tianshan-Hingan seaway coupled with the collision and amalgamation of Siberia with North China and the Tarim block, in a manner much like closing a pair of scissors with the closure of the seaway proceeding gradually and progressively from west to the east.