Effect of grain size on deformation twinning in a magnesium alloy and commercial purity titanium

This data collection contains several optical microstructure images, EBSD maps and stress-strain curves. The research involves collecting data from samples with different grain sizes at several values of plastic strains to measure some important twinning parameters such as twin volume fraction and number of twins per grain. The aim of this study is to investigate the effect of grain size on deformation twinning behaviour in two hcp metals i.e. commercial purity titanium and AZ31 magnesium alloy.

Influence of grain size and training temperature on strain of polycrystalline Ni50Mn29Ga21 samples

The alloy Ni-Mn-Ga aroused great interest for application as a magnetic shape memory (MSM) material. This effect is caused by reorientation of twin variants by an external magnetic field. So far, most of the experiments were concentrated on single crystals. But, the MSM effect can also be realised in polycrystals which can be prepared much more efficiently. Here, polycrystalline samples were prepared by directional solidification with a <100> fibre texture of the high temperature cubic austenitic phase parallel to the heat flow. Afterwards, a heat treatment was applied for chemical homogenisation and stress relaxation in the austenitic state. Then the samples were heated up to the austenitic state and cooled down under load. The microstructure was analysed by Electron Back Scatter Diffraction (EBSD) before and after that treatment. Mechanical training at room temperature and 40°C was tracked by recording stress-strain curves. By increasing the number of training cycles the strain also increases. The influence of different training temperatures was investigated on samples with different grain sizes.

Adaptive patch size determination for patch-based image completion

Patch-based image completion proceeds by iteratively filling the target (unknown) region by the best matching patches in the source image. In most existing such algorithms, the size of the patches is either fixed and specified by a default number or simply chosen to be inversely proportional to the spatial frequency. However, it is noted that the patch size affects how well the filled patch captures the local characteristics of the source image and thus the final completion accuracy. Thus in this paper we propose a new method to compute appropriate patch sizes for image completion to improve its performance. In particular, we formulate the patch size determination as an optimization problem that minimizes an objective function involving image gradients and distinct and homogenous features. Experimental results show that our method can provide a significant enhancement to patch-based image completion algorithms.

The role of cultural values and religion on views of body size and eating practices among adolescents from Fiji, Tonga and Australia

Objectives This study investigated cultural values related to body image and eating practices in Western and non-Western societies.

Design and Methods In total, 628 Fijian, 463 Indo-Fijian, 598 Tongan, and 534 Australian adolescents completed measures of cultural values and religious influences in relation to the ideal body and eating practices.

Results Fijian and Tongan adolescents were more likely to value a large body. Religious influences were most strongly associated with eating practices for Fijians, Indo-Fijians, and Tongans.

Conclusions The findings support the role of religion in transmitting cultural values regarding eating practices in Pacific Island communities.

Statement of contribution
What is already known on this subject? Previous research has demonstrated that sociocultural factors shape body image and eating behaviours. Most of this research has been conducted in Western countries.

What does this study add? The current study identifies the role of cultural values and religious influences on body image and eating behaviours in a number of different cultural groups. This is the first study to use the same methodology to explore these relationships across Western and Pacific Island communities.

Clutch size for Mediterranean loggerhead turtles (Caretta caretta)

We investigated the number of eggs laid and the total clutch volume for loggerhead turtles (Caretta caretta L.) nesting on the Greek island of Cephalonia (38° 09′ N, 20° 33′ E) during 1990. Both the number of eggs laid and clutch volume were positively related to female body size, and the mean explained variation for these relationships (36·6% and 37·7%, respectively) were not significantly different. Clutch volume decreased as the season progressed because individuals laid successively smaller clutches. The inter-nesting interval (range 15–19 days) did not significantly influence the number of eggs laid or clutch volume. For individuals seen laying more than once, female size in combination with the number of a clutch in relation to all the clutches observed for that individual, together explained 65·5% of the variation in clutch volume.

Reproductive investment and optimum clutch size of Loggerhead Sea Turtles (Caretta caretta)

(1) Data for loggerhead turtles (Caretta caretta L.) nesting on the Greek island of Cephalonia were used to develop a model which predicted the optimum clutch size. (2) There was a positive linear relationship between the number of clutches into which eggs could be divided and the total time spent by a nesting turtle on the beach, and hence a negative relationship between the time invested on the beach per egg and clutch size. (3) A previous study indicated that energy expenditure for nesting turtles on land is very high, so there may be a selective pressure to maximize clutch size in order to minimize the energy expended per egg laid. As there appeared to be no counterselective pressures favouring small clutches, clutch size should be constrained by a female's egg-carryingc apacity,w hich in turn could be expected to be related to her body size. Hence, a positive relationship between clutch size and body size was predicted, and was found in the population under study.

Bias and size effects of price-comparison search engines : theory and experimental evidence

We analyze the impact on consumer prices of the size and bias of price comparison search engines. In the context of a model related to Burdett and Judd (1983) and Varian (1980), we develop and test experimentally several theoretical predictions. The experimental results confirm the model’s predictions regarding the impact of the number of firms, and the type of bias of the search engine, but reject the model’s predictions regarding changes in the size of the index. The explanatory power of an econometric model for the price distributions is significantly improved when variables accounting for risk attitudes are introduced.

Retrievals of a size parameter for phytoplankton and spectral light absorption by colored detrital matter from water-leaving radiances at SeaWiFS channels in a continental shelf region off Brazil

Many efforts are currently oriented toward extracting more information from ocean color than the chlorophyll a concentration. Among biological parameters potentially accessible from space, estimates of phytoplankton cell size and light absorption by colored detrital matter (CDM) would lead to an indirect assessment of major components of the organic carbon pool in the ocean, which would benefit oceanic carbon budget models. We present here 2 procedures to retrieve simultaneously from ocean color measurements in a limited number of bands, magnitudes, and spectral shapes for both light absorption by CDM and phytoplankton, along with a size parameter for phytoplankton. The performance of the 2 procedures was evaluated using different data sets that correspond to increasing uncertainties: ( 1) measured absorption coefficients of phytoplankton, particulate detritus, and colored dissolved organic matter ( CDOM) and measured chlorophyll a concentrations and ( 2) SeaWiFS upwelling radiance measurements and chlorophyll a concentrations estimated from global algorithms. In situ data were acquired during 3 cruises, differing by their relative proportions in CDM and phytoplankton, over a continental shelf off Brazil. No local information was introduced in either procedure, to make them more generally applicable. Over the study area, the absorption coefficient of CDM at 443 nm was retrieved from SeaWiFS radiances with a relative root mean square error (RMSE) of 33%, and phytoplankton light absorption coefficients in SeaWiFS bands ( from 412 to 510 nm) were retrieved with RMSEs between 28% and 33%. These results are comparable to or better than those obtained by 3 published models. In addition, a size parameter of phytoplankton and the spectral slope of CDM absorption were retrieved with RMSEs of 17% and 22%, respectively. If these methods are applied at a regional scale, the performances could be substantially improved by locally tuning some empirical relationships.

Stomach fullness modulates prey size choice in the frillfin goby, Bathygobius soporator

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Dinoponera lucida Emery (Formicidae : Ponerinae): the highest number of chromosomes known in Hymenoptera

We report the remarkable karyotype of Dinoponera lucida, a Brazilian endemic ponerine ant. Its chromosome number is 2n=106, most of the chromosomes are acrocentric and of very small size, and the karyotype formula is 88A+18M. A chromosome pair of the AM(t) type is reported. This is the largest number of chromosomes reported for the Hymenoptera order until now.

Relationship between follicle size and ultrasound-guided transvaginal oocyte recovery

We evaluated the relationship between follicle size and oocyte recovery (OR) using ultrasound-guided follicle aspiration. Thirty Holstein cows were subjected to OR without gonadotrophic therapy. Oocytes were recovered two to four times from each cow in a total of 67 aspiration sessions, Ovarian follicles with diameters less than or equal to4 mm and >4 mm were aspirated in separated groups. Recovered oocytes from each group were kept separate and submitted to in vitro maturation, fertilization, and culture to the blastocyst stage. A total of 430 follicles were aspirated, of which 154 (35.8%) were from follicles >4 mm and 276 (64.2%) were from follicles less than or equal to4 mm. Seventy-seven oocytes (50%) were recovered from follicles >4 mm and 200 (72.2%) were from follicles less than or equal to4 mm. Nineteen blastocysts were obtained from follicles >4 mm, whereas 45 blastocysts were obtained from follicles less than or equal to4 mm. Recovery rate was greater (P < 0.01) in follicles less than or equal to4 mm, Oocyte quality, cleavage rate and blastocyst development did not differ between different follicle sizes. Routine aspiration of small follicles (less than or equal to4 mm) could increase the number of oocytes available for in vitro development. (C) 2001 Elsevier B.V. B.V. All rights reserved.

Effects of corn particle size and physical form of the diet on the gastrointestinal structures of broiler chickens

The objective of this experiment was to investigate the effects of different particle sizes, expressed as Geometric Mean Diameter (GMD) of corn (0.336mm, 0.585mm, 0.856mm and 1.12mm) of mash and pelleted broiler chicken diets on the weight of the gizzard, duodenum and jejunum+ileum; on the pH of the gizzard and small intestine and on the characteristics of the duodenal mucous layer (number and height of villi and crypt depth) in 42-day-old broilers. The physical form and the particle size of the diet had no significant effect on gizzard and intestine pH (p > 0.05). A greater gizzard weight was seen in the birds receiving pelleted diet and particle size of 0.336mm (p < 0.008). However, for the particle sizes of 0.856 and 1.12 mm, a greater weight was found in birds that received mash diet (p < 0.039 and p < 0.006, respectively). Also, gizzard weight was greater with increasing corn GMD independent of the physical form of the diet. In the mash diet, the increase in particle size promoted a quadratic response in the weight of duodenum and jejunum + ileum. The pelleted diet promoted a greater number of villi per transverse duodenum cut (p < 0.007) and greater crypt depth (p < 0.05). As the particle size increased, there was a linear increase of villus height and crypt depth in the duodenum, irrespective of the physical form of the diet.

Relationship Between Population Size and Symbiont Fungus Culture Volume in Colonies of Acromyrmex balzani (Hymenoptera: Formicidae)

In order to quantify the population of Acromyrmex balzani Emery, 1890 nests and to verify whether the population dynamic of the colony is correlated with the symbiont fungus volume, the principal energy source of the colony, five nests located in grassland areas were evaluated. The nests were sprayed with neutral talcum powder to improve visualization and digging. The symbiont fungus and the entire population existent in the chambers were collected. The mean fungus volume and total nest population in excavated nests were, respectively, 74.76 ml and 1,095 individuals. Simple linear correlation analysis verified that the fungus volume grew proportionally to the number of individuals. Despite the correlation between fungus volume and population dynamic of colonies, the factors that determine this relationship are little known since other microorganisms live in association with the colony.

Internal Architecture and Population Size of Acromyrmex subterraneus molestans (Hymenoptera, Formicidae) Nests: Comparison Between a Rural and an Urban Area

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Correlation of microcrack fracture size with fatigue cycling on non-crimp fabric/RTM6 composite in the uniaxial fatigue test

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)