Marine rocky intertidal organisms are amongst those most affected by climate change with regional distributional changes observed for many species. Although often ascribed to increased sea surface ...temperatures, precise assessment of the local habitat conditions underpinning observed and predicted changes in community assembly is lacking. Here we examine how aspect (i.e. north-south orientation) affects intertidal community composition and how rock surface temperatures and stress responses of two dominant grazer species (Patella spp.) elucidate emergent differences. We quantified year-round temperature variation and surveyed intertidal community composition on paired natural rock gullies with Equator- (EF) and Pole-facing (PF) surfaces. We also investigated variation in limpet (Patella spp.) reproductive phenology and osmotic stress. Average annual temperatures were 0.8 °C (1.6 °C at low tide) higher, with six-fold more frequent extremes (i.e. > 30 °C) on EF than PF surfaces. Intertidal community composition varied with aspect across trophic levels with greater overall species richness, abundance of primary producers and grazers on PF-surfaces, and greater barnacle abundance on EF-surfaces. Although species richness of organisms from different biogeographical origins (‘Boreal’ or ‘Lusitanian’) did not vary, the Lusitanian limpet Patella depressa exhibited earlier reproductive development on EF-surfaces and both limpet species exhibited greater thermal stress on EF-surfaces. We argue that our study system provides a good model for understanding how temperature variation at local scales can affect community composition, as well as ecophysiological and ecological responses to climate change and so better inform and predict regional range shifts over coming decades.
•Both average annual and frequency of extreme temperatures significantly varies with aspect surface.•Intertidal community composition changes with aspect.•Greater overall species richness and abundance of primary producers and grazers on cooler pole-facing surfaces.•Limpets display phenological shifts and osmotic stress in response to aspect.
Parmigiano Reggiano cheese dairies develop specific cheese-making strategies to adapt the variable characteristics of raw, not standardized milk to the final goal of obtaining cheese consistent with ...the standard. Analyzing 1,175 cheese-making reports from 30 out of 383 dairies associated with the Parmigiano Reggiano Consortium in 2010 and 2011, 4 groups of Parmigiano Reggiano dairies using specific cheese-making technologies were discriminated by means of multiple linear discriminant analysis. Cheese makers manage cheese-making practices to obtain curd with different roughness properties, classified according to jargon words such as “rigata” and “giusta” or synonyms, because they believe that the roughness of the cheese curd surface immediately after the extraction from the vat is associated with different whey-draining properties and to the final outcome of the cheese. The aspect of the surfaces of the curds produced by the 4 groups of dairies was different according to the technology applied by each group. Cutting of the coagulum when it is still soft for a longer time and faster cooking of the cheese curd grains were associated with a less rough appearance of the surface of the curd, whereas under the opposite conditions, cutting the coagulum when it is firm for a shorter time, led to a curd with a rougher surface. These findings partially support the traditional feeling of Parmigiano Reggiano cheese makers, who consider the curd surface aspect one of the main drivers for their technological choices; to date, however, no data are provided about correlation between the aspect of the curd and the quality of the ripened cheese. If a sufficiently strong correlation could be demonstrated by the future development of the research, the operational effectiveness of Parmigiano Reggiano dairies will be able to largely benefit from the availability of sound and early process markers.
The surface modification of engine cylinder bores with improved sliding properties is often produced by the honing process. This multi-stage process is performed using abrasive stones loaded against ...the bore with simultaneous rotation and oscillation. To guarantee this process robustness with acceptable dimensional accuracy and surface quality, the stone dynamic effects in continuous balanced contact with the workpiece have to be studied deeply. This paper highlights these effects on honed surface textures. The stone dynamic behavior was studied at conventional regime ranged from 0.5g to 1.5g as often used in mass production. In this range, the dimensional accuracy is ensured by opposition to the surface appearance. However, higher accelerations up to 2.5g improve simultaneously the form quality (especially straightness) and reduce the cycle time. This work shows, at least, that the bore surface finish can be dynamically controlled while honing. This technology is enabled by a micro scale regeneration mechanism of abrasive stones.
► Impact of stroke dynamic on honed surface roughness ► Impact of stroke dynamic on honed surface texture ► Cylinder honed quality in function of honing process parameters
A consistent increase in demand for special tools designed to enhance an efficient honing of engine cylinder bores is observed. Metallic Bonded Diamond Stones (Dia-M) are more and more used for their ...wear resistance and their high tool life. However, the hardness of this Metallic Bond leads to the degradation of the honed surface aspect by the formation of smudgy grooves edges (blechmantel). This torn and folded metal affects the required functional performances of the cylinder bore. In this study, two new diamond coated abrasive stones with Vitrified and Resinoid Bonds (respectively Dia-V and Dia-R) are tested and compared to the Dia-M sticks. The influences of bond material on the honing reliability are studied in terms of honed surface aspect, material removal rate and wear properties. Results reveal that the stiffness and the openness structure of the Resinoid Bond leads to a better trade off between surface aspect and tool life.
In this work, three Cu–Sn–Fe–Ni matrices with different hardness were utilized in the diamond honing stones. Structures of the three matrices were investigated by X-ray diffraction, energy dispersive ...spectroscopy and scanning electron microscopy, and the results showed that the Cu–Sn–Fe–Ni matrices were composed of the pure copper, pure iron and (Cu, Ni)
41
Sn
11
. The wear properties of the matrices were estimated by a pin-on-disk wear machine under dry conditions at room temperature in the air. The influences of hardness on the honing performances were studied in terms of the honed surface aspect, the honing efficiency and the throughput of cylinder liners. Among the three stones, the stone with matrix B (HRB 71) reaches the self-sharpening range in terms of the three aspects mentioned above. Compared this stone with a commercially available product, the former has better honing efficiency.
This book describes some basic morphometric characteristics of Slovenia’s surface relative to its landscape types using a geographic information system and digital elevation model. The book compares ...the more recent 25-meter digital elevation model and the older 100-meter digital elevation model. Statistical analysis of the two digital elevation models of Slovenia indicates that the smallest differences exist relative to surface heights, that there are larger differences relative to surface aspects, and that the largest differences exist relative to surface slopes.
It is practically difficult to properly seat the full cast crown on the prepared tooth by means of a luting cement. We have devised the double-crown system consisting of an inner crown and an outer ...crown to aid better seating of the crown restoration. It can minimize the elevation of the inner crown at the margin, because its open occlusal plane allows the cement slurry to easily overflow. Although the inner crown should be very thin, it is not easy to fabricate it precisely by casting. In this study, therefore, the application of the sintering procedure by powder metallurgy to the formation of the inner crown was evaluated in terms of marginal fit before and after cementation and surface aspect. The results obtained were as follows : 1. There were no significant differences in the try-in marginal fit between the full cast crown, cast inner crown and sintered inner crown. 2. Both the cast and sintered inner crowns showed a small elevation at their margins by cementation, while significantly larger elevation was found in the cast full crown. 3. The surface roughness test and SEM observation revealed no obvious differences in the metal surface aspect between the sintering and casting method procedures. It was suggested from the foregoing results that the powder metallurgy could be effectively available for easily making the inner crown in the double-crown system.
The effects of casting temperature were studied on the surface aspects and casting porosities of Ag-Pd-Au alloy cast crown.The alloy was centrifugally cast at two different temperatures, 1, 000℃ and ...1, 200℃.These temperatures were selected on the basis of the casting temperature range determined by the molten alloy appearance in the previous study.The crown surface was entirely covered with dark copper and zinc oxides, and no chages were found in surface appearance by altering the casting temperature or adding flux.On the other hand, the oxides on the button surface were apparently decreased by the use of the flux only when the alloy was cast at 1, 000℃.The castings made at 1, 200℃ were characterized by thicker oxide laxers on the upper surface of the button, extensive burning of the investment on the bottom surface of the button, and marked casting porosities on the occlusal subsurface of the crown.The flux was no more effective for protecting the alloy from oxidation at 1, 200℃, although the porosities were considerably reduced.
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