Influence of posture on the range of axial rotation and coupled lateral flexion of the thoracic spine

Objective
This study examines the influence of posture on the range of axial rotation of the thorax and the range and direction of the coupled lateral flexion.

Methods
The ranges of mid thoracic axial rotation and coupled lateral flexion were measured in 52 asymptomatic subjects (aged 18-43 years) using an optical motion analysis system. To examine the influence of posture on primary and coupled motion, we initiated axial rotation from a neutral sitting posture and from end-range thoracic flexion and extension.

Results
There was a significant decrease in the range of thoracic rotation in flexion compared with the neutral and extended postures (P < .001). The mean range of coupled lateral flexion was 8.9% of the axial rotation range in the neutral posture and increased to 14.3% and 23.2% in the extended and flexed postures, respectively. Patterns of coupled motion varied between subjects, but an ipsilateral pattern was more common in the flexed posture, whereas a contralateral pattern was more common in the neutral and extended postures.

Conclusions
The ranges and patterns of coupled motion of the thorax appear to be strongly influenced by the posture from which the movement is initiated. This has important implications in relation to the interpretation of clinical tests of thoracic motion and in consideration of mechanisms of development of thoracic pain disorders.

Effects of clay amendment on adsorption and desorption of copper in water repellent soils

Copper is an important micronutrient and trace amounts are essential for crop growth. However, high concentrations of copper will produce toxic effects. Australia is increasingly developing production of crops in water repellent soils. Clay amendment, a common amelioration techniques used in Australia, has demonstrated agronomic benefits in increased crop or pasture production. The sorption and desorption of copper and the effect of clay treatment on copper behaviour in a water repellent soil collected from an experimental farm in South Australia is studied. We found that the water repellent soils amended with clay have an increased adsorption capacity of copper. Also the clay-amended soils had an increased ratio of specific sorption to total sorption of copper. The implications of this study to the sustainable agro-environmental management of water repellent soils is discussed.

Permian Chonetoidea and Spiriferoidea of Australasia : Gondwanan relationships, provincialism, palaeobiogeography

Members of the Spiriferoidea are dominant in the Permian marine invertebrate faunas of Australia. Genera can be endemic to a particular province, demonstrate a wider Gondwanan and peri-Gondwanan distribution and several indicate a bipolar distribution. Australasian spiriferoids are included within the families Spiriferidae, Neospiriferidae, Trigonotretidae and the Spiriferellidae. Several genera and species are the largest spirferoids ever recorded. Few genera are shared between the Westralian and Austrazean provinces but a higher proportion of genera are shared between the Westralian province and the Cimmerian Realm.
Representatives of the Chonetoidea are a less common but significant element of the faunas. They were used over 20 years ago to define the Westralian and Austrazean provinces of Australasia – concepts that are in widespread use today. The Paratinan and Cimmerian provinces were also defined at that time despite difficulties in their definition. Through more recent studies the Cimmerian Province has been upgraded to a Realm while the Paratinan Province is more clearly defined for the earliest Permian, based on the chonetoids of Patagonia and western and eastern central Argentina.
Distribution of the various genera is best explained by an interplay of factors including surface and deeper oceanic currents, marine water temperatures and tectonic events such as the clockwise rotation of Gondwanan and the dispersal of the peri-Gondwanan Cimmerian terranes. Austrazean faunas developed in isolation under the influence of cooler and cold waters during the early Permian. Late Permian faunas demonstrated more widespread linkages.

Needleless-electrospinning of PVA nanofibres

In this paper, we demonstrated that a thin metal disk can be used as nozzle to electrospin PVA nanofibres on a large-scale. With the rotation of a disk covered with a thin layer of electrically charged PVA solution, a large number of fibres were electrospun simultaneously from two sides of the disk and deposited on the electrode collector. The fibre production rate can be as high as 6.0 glhr, which is about 270 times higher than that of a corresponding normal needle based electrospinning system (0.022 g/hr). The effects of applied voltage, the distance between the disk nozzle and collector, and PVA concentration on the fibre morphology were examined. The dependency of fibre diameter on the PV A concentration showed a similar trend to that for a conventional electrospinning system using a syringe needle nozzle, but the diameter distribution was slightly wider for the disk electrospun fibres. The profiles of electric field strength in disk electrospinning showed considerable dependence on the disk thickness, with a thin disk exhibiting similar electric field strength profile to that of a needle electrospinning system.

The robustness of objective fabric pilling evaluation method

Previously, we proposed a new method to identify fabric pilling and objectively measure fabric pilling intensity based on the two-dimensional dual-tree complex wavelet reconstruction and neural network classification. Here we further evaluate the robustness of the method. Our results indicate that the pilling identification method is robust to significant variation in the brightness and contrast of the image, rotation of the image, and 2 i (i is an integer) times dilation of the image. The pilling feature vector developed to characterize the pilling intensity is robust to brightness change but is sensitive to large rotations of the image. As long as all fabric images are adjusted to have the same contrast level and the sample is illuminated from the same direction, the pilling feature vectors are comparable and can be used to classify the pilling intensity.

EBSD and TEM investigation of the hot deformation substructure characteristics of a type 316L austenitic stainless steel

The evolution of crystallographic texture and deformation substructure was studied in a type 316L austenitic stainless steel, deformed in rolling at 900 °C to true strain levels of about 0.3 and 0.7. Electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM) were used in the investigation and a comparison of the substructural characteristics obtained by these techniques was made. At the lower strain level, the deformation substructure observed by EBSD appeared to be rather poorly developed. There was considerable evidence of a rotation of the pre-existing twin boundaries from their original orientation relationship, as well as the formation of highly distorted grain boundary regions. In TEM, at this strain level, the substructure was more clearly revealed, although it appeared rather inhomogeneously developed from grain to grain. The subgrains were frequently elongated and their boundaries often approximated to traces of {111} slip planes. The corresponding misorientations were small and largely displayed a non-cumulative character. At the larger strain, the substructure within most grains became well developed and the corresponding misorientations increased. This resulted in better detection of sub-boundaries by EBSD, although the percentage of indexing slightly decreased. TEM revealed splitting of some sub-boundaries to form fine microbands, as well as the localized formation of microshear bands. The substructural characteristics observed by EBSD, in particular at the larger strain, generally appeared to compare well with those obtained using TEM. With increased strain level, the mean subgrain size became finer, the corresponding mean misorientation angle increased and both these characteristics became less dependent on a particular grain orientation. The statistically representative data obtained will assist in the development of physically based models of microstructural evolution during thermomechanical processing of austenitic stainless steels.

Fruitful use of bioacoustic alarm stimuli as a deterrent for Crimson Rosellas (Platycercus elegans)

Birds cause considerable damage to horticultural crops in Australia each year. The playback of species-specific bioacoustic alarm stimuli has been one of the most promising methods suggested to deal with bird-problems. However, no published studies have tested this method on species of parrots, one of the main avian pests of crops in Australia and globally. Furthermore the effectiveness of this method might be reduced if alarm calls were played back that came from a non-local population. The Crimson Rosella species complex (Platycercus elegans), a parrot with considerable acoustic variation throughout its range, is considered a pest species of several commercial fruit crops. This study tested whether alarm calls from Crimson Rosellas were effective in reducing the activity of Rosellas in apple orchards. Three groups of bioacoustic stimuli were compared: control stimuli, local alarm calls and non-local alarm calls. Our results indicate that the playback of alarm calls from Crimson Rosellas is effective in reducing the activity of Rosellas in orchards over the period of study, and we did not find any difference between the use of local and non-local alarm calls. Our study suggests that playback of alarm calls may be an effective deterrent of rosellas over a broad distribution, at least for short- to medium-term use.

Recognition from appearance subspaces across image sets of variable scale

Linear subspace representations of appearance variation are pervasive in computer vision. In this paper we address the problem of robustly matching them (computing the similarity between them) when they correspond to sets of images of different (possibly greatly so) scales. We show that the naïve solution of projecting the low-scale subspace into the high-scale image space is inadequate, especially at large scale discrepancies. A successful approach is proposed instead. It consists of (i) an interpolated projection of the low-scale subspace into the high-scale space, which is followed by (ii) a rotation of this initial estimate within the bounds of the imposed “downsampling constraint”. The optimal rotation is found in the closed-form which best aligns the high-scale reconstruction of the low-scale subspace with the reference it is compared to. The proposed method is evaluated on the problem of matching sets of face appearances under varying illumination. In comparison to the naïve matching, our algorithm is shown to greatly increase the separation of between-class and within-class similarities, as well as produce far more meaningful modes of common appearance on which the match score is based.

A discrete simulation approach to spatial allocation of commodity production for revenue optimisation over a local region

A simulation approach is described for the spatial allocation of crops across a region in order to maximise total revenue. The model uses inputs from GIS-based land suitability analysis to provide data on yields for a range of commodities, where the land suitability for the crops can be determined by either biophysical models or multi-criteria analysis. The objective of the study was to gain some indication of the magnitude of improvement possible in revenue, based on the convergence results for the optimisation (subject to estimated production quantities and market prices). The basic structure of the model allows for scaling up to larger problems with additional inputs and finer cell resolution. The software produces a visualisation of crop spatial allocation across the region and is compatible with statistical uncertainty analysis. The results of model simulations revealed a significant increase in revenue is possible using this approach and, when projected over the full region, suggests the possibility of significant economic benefits.

Comparative analyses of cadmium and zinc uptake correlated with changes in natural resistance-associated macrophage protein (NRAMP) expression in Solanum nigrum L. and Brassica rapa

Environmental context Soils contaminated with metals can pose both environmental and human health risks. This study showed that a common crop vegetable grown in the presence of cadmium and zinc readily accumulated these metals, and thus could be a source of toxicity when eaten. The work highlights potential health risks from consuming crops grown on contaminated soils. Abstract Ingestion of plants grown in heavy metal contaminated soils can cause toxicity because of metal accumulation. We compared Cd and Zn levels in Brassica rapa, a widely grown crop vegetable, with that of the hyperaccumulator Solanum nigrum L. Solanum nigrum contained 4 times more Zn and 12 times more Cd than B. rapa, relative to dry mass. In S. nigrum Cd and Zn preferentially accumulated in the roots whereas in B. rapa Cd and Zn were concentrated more in the shoots than in the roots. The different distribution of Cd and Zn in B. rapa and S. nigrum suggests the presence of distinct metal uptake mechanisms. We correlated plant metal content with the expression of a conserved putative natural resistance-associated macrophage protein (NRAMP) metal transporter in both plants. Treatment of both plants with either Cd or Zn increased expression of the NRAMP, with expression levels being higher in the roots than in the shoots. These findings provide insights into the molecular mechanisms of heavy metal processing by S. nigrum L. and the crop vegetable B. rapa that could assist in application of these plants for phytoremediation. These investigations also highlight potential health risks associated with the consumption of crops grown on contaminated soils.

On the feasibility of utilising gearing to extend the rotational workspace of a class of parallel robots

Parallel manipulators provide several benefits compared to serial manipulators of similar size. These advantages typically include higher speed and acceleration, improved position accuracy and increased stiffness. However, parallel manipulators also suffer from several disadvantages. These drawbacks commonly include a small ratio of the positional workspace relative to the manipulator footprint and a limited rotational capability of the manipulated platform. A few parallel manipulators featuring a large ratio of the positional workspace relative to the footprint have been proposed. This paper investigates the feasibility of employing gearing to extend the range of the end-effector rotation of such mechanisms. The objective is to achieve parallel manipulators where both the positional and rotational workspace are comparable to that of serial manipulators.

Symmetric and asymmetric rolling of low carbon steels

 In this study, it is shown that a close to ideal shear texture can be formed throughout the thickness of a rolled sheet. Such rotation of rolling texture not only leads to the enhancement in grain refinement but also the secondary processing as compared to the symmetric rolling.

A kinematics study of variable lead axisymmetric forward spiral extrusion

Variable lead axi-symmetric forward spiral extrusion (VLAFSE) allows far more efficient strain accumulation than constant lead counterpart AFSE. It eliminates the rigid body rotation of the sample in an AFSE die which only causes frictional loss and has no contribution to the deformation. Based on a proposed velocity field, the kinematic formulation for VLAFSE is presented, utilized to predict strain components in the deformation zone and compared with experimental measurements. A simple closed form solution of the VLAFSE problem is presented which describes the flow of material inside the extrusion die. The results confirm that the effective strain of the process accumulates non-linearly in the both radial and extrusion directions.

Microstructure and texture evolution during symmetric and asymmetric rolling of a martensitic Ti-6Al-4V alloy

In the current study, the effect of deformation mode (i.e., symmetric vs asymmetric rolling) on the extent of grain refinement and texture development in Ti-6Al-4V was examined through warm rolling of a martensitic starting microstructure. During rolling, the initial martensitic lath structure was progressively fragmented, primarily through continuous dynamic recrystallization. This eventually led to an ultrafine-grained (UFG) microstructure composed of equiaxed grains with a mean size of 180 to 230 nm, mostly surrounded by high-angle grain boundaries. Depending on the rolling reduction and deformation mode (symmetric and asymmetric), the rolled specimens displayed different layer morphologies throughout the specimen thickness: a fully UFG surface layer, a partial UFG transition layer, and a partially fragmented lath interior layer. Due to a higher level of effective strain and continuous rotation of the principle axis, asymmetric rolling resulted in a greater extent of grain refinement compared with symmetric rolling at a given thermomechanical condition. A bulk UFG structure was successfully obtained using 70 pct asymmetric rolling. In addition, the rolling texture exhibited various characteristics throughout the thickness due to a different combination of shear and compressive strains. Principally, the basal texture component was displaced from the normal toward rolling direction during asymmetric rolling, differing from the symmetric rolling textures.

EBSD and AFM observations of the microstructural changes induced by low temperature plasma carburising on AISI 316

Low temperature plasma carburising (LTPC) has been increasingly accepted as a hardening process for austenitic stainless steels because it produces a good combination of tribological and corrosion properties. The hardening mechanism is based on the supersaturation of the austenitic structure with carbon, which greatly hardens the material, significantly expands the fcc unit cell, produces high levels of compressive residual stresses and, ultimately, leads to the occurrence of deformation bands and rotation of the crystal lattice. The microstructural changes introduced during plasma carburising have a significant impact on the mechanical, tribological and corrosion performance and, for this reason, the microstructure of expanded austenite or S-phase has been extensively studied. However, modern surface characterisation techniques could provide new insights into the formation mechanism of S-phase layers. In this work, backscattered electron diffraction and atomic force microscopy were used to characterise the surface layers of expanded austenite produced by LTPC in an active screen furnace. Based on the experimental results, the plastic deformation, its dependence on crystallographic orientation, the evolution of grain boundaries, and their effects on mechanical, tribological and corrosion properties are discussed. © 2011 Elsevier B.V. All rights reserved.