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Shear Force (shear + force)
Terms modified by Shear Force Selected AbstractsEffect of Perpendicular Shear Force on the Interfacial Morphology of Reactive Polymer BilayerMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 7 2008Hwang Yong Kim Abstract We investigated the effect of shear forces perpendicular to the interface on the interfacial morphology of a reactive bilayer. It was observed that the perpendicular shear force greatly enhanced the roughness of the interface compared with parallel shear force. The main role of in situ formed graft copolymers is not to increase greatly the roughness of the interface, but to stabilize the interfacial morphology. We also observed that microemuslsions were observed at both the PMMA and PS layers, which is distinctly different from the situation obtained under parallel shear force (or without shear) that the microemlusions were seen in only the PMMA layer. [source] Effect of single nucleotide polymorphisms of CAPN1 and CAST genes on meat traits in Nellore beef cattle (Bos indicus) and in their crosses with Bos taurusANIMAL GENETICS, Issue 4 2009R. A. Curi Summary The objectives of this work were to study the segregation of single nucleotide polymorphisms of the calpain 1, large subunit (CAPN1) and calpastatin (CAST) genes in Nellore (Bos indicus) and Nellore ×Bos taurus beef cattle, as well as to evaluate their effects on meat traits. For this, 300 animals, including 114 Nellore, 67 Angus × Nellore, 44 Rubia Gallega × Nellore, 41 Canchim, 19 Brangus three-way crosses and 15 Braunvieh three-way crosses, were genotyped for the CAPN4751 [AF_248054.2:g.6545C>T (GenBank accession AF248054.2)] and CAST/DdeI [AF_159246.1:g.2959A>G (GenBank accession AF159246.1)] polymorphisms and phenotyped for Ribeye Area, Backfat Thickness, Intramuscular Fat, Shear Force (SF) and Myofibrillar Fragmentation Index (MFI). In relation to the CAPN4751 polymorphism, a frequency of 10.5% was observed for the C allele in the Nellore breed. In the total sample of studied animals, a significant association was found between genotypes and meat tenderness, assessed by SF (P = 0.005) and MFI (P = 0.008), with genotype CT being more favourable than TT. For the CAST/DdeI polymorphism, a frequency of 55.7% was found for the A allele in the Nellore breed. In the total sample, a significant association was observed between genotypes and meat tenderness , SF (P = 0.004) and MFI (P = 0.006), with genotype AA being more favourable than AG. The relationship between genotypes and aged meat tenderness in confluence with the distribution of favourable alleles shows great potential for application of the CAPN4751 and CAST/DdeI polymorphisms in the genetic improvement of the Nellore breed, whilst contributing to the validation, in this breed and in its crosses with B. taurus, of the association results previously described in the literature. [source] Ein Bemessungsansatz für zweiachsig durch Querkräfte beanspruchte Stahlbetonbalken mit RechteckquerschnittBETON- UND STAHLBETONBAU, Issue 5 2005Peter Mark Dr.-Ing. Für Stahlbetonbalken mit Rechteckquerschnitt und üblichen zweischnittigen Bügeln wird ein Ansatz zur Bemessung gegen geneigt zu den Hauptachsen einwirkende Querkräfte abgeleitet und an Simulationsrechnungen und Experimenten verifiziert. Der Ansatz basiert auf dem der DIN 1045-1 zugrunde liegenden "Fachwerkmodell mit Rißreibung" und ergänzt zur Berücksichtigung einer Querkraftneigung die Gleichungen der Querkraftwiderstände nach DIN 1045-1 durch einfache Faktoren aus Geometrie- und Lastgrößen. Ein Beispiel zeigt, daß die Widerstände merklich abnehmen bzw. höhere Bügelbewehrungsmengen erforderlich sind, falls die Querkraft von einer hauptachsenparallelen Wirkungsrichtung abweicht. Design of Reinforced Concrete Beams with rectangular Cross Sections against biaxial Shear Forces An approach is presented to design reinforced concrete beams with rectangular cross sections and usual stirrups against shear forces that act inclined to the principal axes of the cross sections. It basis on the "truss model with crack friction" and adds supplementary terms to the equations of the shear resistances acc. to DIN 1045-1 to take account for shear force inclinations. Verifications to experimental as well as numerical data are given. An example shows that resistances evidently decrease , or higher amounts of stirrup reinforcement become necessary ,, if shear forces deviate from principal axes. [source] Dry-Aging Effects on Palatability of Beef Longissimus MuscleJOURNAL OF FOOD SCIENCE, Issue 2 2001R.E. Campbell ABSTRACT: Beef strip loins and short loins were vacuum aged for 7 or 14 d, then these cuts were dry aged for 7, 14, or 21 d. At 2, 9, and 16 d of post-dry-aging vacuum storage, strip steaks were analyzed for sensory, physical, and microbial differences. Controls were vacuum aged for 14 d. Dry aging for 14 and 21 d produced steaks with greater (P < 0.05) dry-aged flavor, tenderness, and juiciness than controls or steaks dry aged for 7 d. Shear forces were lower (P < 0.05) for steaks dry aged for 21 d. Time of vacuum storage before and after dry aging had minimal effects on development of dry-aged flavor attributes. [source] An investigation of tuned liquid dampers equipped with damping screens under 2D excitationEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 7 2005M. J. Tait Abstract This paper reports on the results of a study conducted on tanks partially filled with water, representing tuned liquid dampers (TLD), subjected to both 1D and 2D horizontal excitations. The sloshing response of the water in the tank is characterized by the free surface motion, the resulting base shear force, and evaluation of the energy dissipated by the sloshing water. A 1D non-linear flow model capable of simulating a TLD equipped with damping screens is employed to model a 2D TLD. Application of this particular model requires the assumption that the response is decoupled and can be treated as the summation of two independent 1D TLDs. Results from the non-linear flow model are compared with the 2D experimental shake table test results leading to a validation of the decoupled response assumption. This attractive decoupled response property allows square and rectangular tanks to be used as 2D TLDs, which can simultaneously reduce the dynamic response of a structure in two perpendicular modes of vibration. Copyright © 2005 John Wiley & Sons, Ltd. [source] Prediction of the maximum credible ground motion in Singapore due to a great Sumatran subduction earthquake: the worst-case scenarioEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 8 2002Kusnowidjaja Megawati Abstract Although Singapore is located in a low-seismicity region, huge but infrequent Sumatran subduction earthquakes might pose structural problems to medium- and high-rise buildings in the city. Based on a series of ground motion simulations of potential earthquakes that may affect Singapore, the 1833 Sumatran subduction earthquake (Mw=9.0) has been identified to be the worst-case scenario earthquake. Bedrock motions in Singapore due to the hypothesized earthquake are simulated using an extended reflectivity method, taking into account uncertainties in source rupture process. Random rupture models, considering the uncertainties in rupture directivity, slip distribution, presence of asperities, rupture velocity and dislocation rise time, are made based on a range of seismologically possible models. The simulated bedrock motions have a very long duration of about 250 s with a predominant period between 1.8 and 2.5 s, which coincides with the natural periods of medium- and high-rise buildings widely found in Singapore. The 90-percentile horizontal peak ground acceleration is estimated to be 33 gal and the 90-percentile horizontal spectral acceleration with 5% damping ratio is 100 gal within the predominant period range. The 90-percentile bedrock motion would generate base shear force higher than that required by the current design code, where seismic design has yet to be considered. This has not taken into account effects of local soil response that might further amplify the bedrock motion. Copyright © 2002 John Wiley & Sons, Ltd. [source] A mathematical hysteretic model for elastomeric isolation bearingsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 4 2002J. S. Hwang Abstract An analytical model for high damping elastomeric isolation bearings is presented in this paper. The model is used to describe mathematically the damping force and restoring force of the rubber material and bearing. Ten parameters to be identified from cyclic loading tests are included in the model. The sensitivity of the ten parameters in affecting the model is examined. These ten parameters are functions of a number of influence factors on the elastomer such as the rubber compound, Mullins effect, scragging effect, frequency, temperature and axial load. In this study, however, only the Mullins effect, scragging effect, frequency and temperature are investigated. Both material tests and shaking table tests were performed to validate the proposed model. Based on the comparison between the experimental and the analytical results, it is found that the proposed analytical model is capable of predicting the shear force,displacement hysteresis very accurately for both rubber material and bearing under cyclic loading reversals. The seismic response time histories of the bearing can also be captured, using the proposed analytical model, with a practically acceptable precision. Copyright © 2002 John Wiley & Sons, Ltd. [source] Elastic half-space under an oblique line impulseINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 12 2003Moche Ziv Abstract This paper presents transient deformation of an elastic half-space under two types of line-concentrated impulsive loads applied simultaneously. One load is a sustainable normal force, while the other is a momentarily applied vector shear force. For each of the two loads the author gave the respective solution in two separate papers. Here the two solutions are superimposed to determine the response of the half-space under the combined loads. The present work is devoted to the salient wave propagation features seen in the resultant computer plots that disclose the strained half-space. Since each critical deformation is explicitly indicated in the plots by a wave front, the interpretation of the response of the half-space to the applied load is readily available at a glance. A comparison is then presented that identifies those deformation traits and wave fronts, among the nineteen here, that are more closely related to those found in previous works. Copyright © 2003 John Wiley & Sons, Ltd. [source] The response of an elastic half-space under a momentary shear line impulseINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 3 2003Moche Ziv Abstract The response of an ideal elastic half-space to a line-concentrated impulsive vector shear force applied momentarily is obtained by an analytical,numerical computational method based on the theory of characteristics in conjunction with kinematical relations derived across surfaces of strong discontinuities. The shear force is concentrated along an infinite line, drawn on the surface of the half-space, while being normal to that line as well as to the axis of symmetry of the half-space. An exact loading model is introduced and built into the computational method for this shear force. With this model, a compatibility exists among the prescribed applied force, the geometric decay of the shear stress component at the precursor shear wave, and the boundary conditions of the half-space; in this sense, the source configuration is exact. For the transient boundary-value problem described above, a wave characteristics formulation is presented, where its differential equations are extended to allow for strong discontinuities which occur in the material motion of the half-space. A numerical integration of these extended differential equations is then carried out in a three-dimensional spatiotemporal wavegrid formed by the Cartesian bicharacteristic curves of the wave characteristics formulation. This work is devoted to the construction of the computational method and to the concepts involved therein, whereas the interpretation of the resultant transient deformation of the half-space is presented in a subsequent paper. Copyright © 2003 John Wiley & Sons, Ltd. [source] A numerical study of wave structures developed on the free surface of a film flowing on inclined planes and subjected to surface shearINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 7 2006N. H. Shuaib Abstract In this work, we determine the different patterns of possible wave structures that can be observed on a thin film flowing on an inclined plane when at the free surface a shear force (surface traction) is applied. Different wave structures are obtained dependening on the selected combination of downstream and upstream boundary conditions and initial conditions. The resulting initial boundary value problems are solved numerically using the direct BEM numerical solution of the complete two-dimensional Stokes system of equations. In our numerical results, the initial discontinuous shock profiles joining uniform fluid depths are smoothed due to the two-dimensional character of the Stokes formulation, including the effect of the gravitational force as well as the interfacial surface tension force. In this way, physically feasible continuous surface profiles are determined, in which the initial uniform depths are joined by smooth moving wave structures. Numerical solutions have been attained to reproduce the different patterns of possible wave structures previously reported in the literature and extended to identify some other new structures and features defining the behaviour of the surface patterns. Copyright © 2006 John Wiley & Sons, Ltd. [source] Decubitus ulcers: A review of the literatureINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 10 2005Cheryl Bansal BA Decubitus ulcers are a worldwide health care concern affecting tens of thousands of patients and costing over a billion dollars a year. Susceptibility to pressure ulcers comes from a combination of external factors (pressure, friction, shear force, and moisture), and internal factors (e.g. fever, malnutrition, anaemia, and endothelial dysfunction). Often, enough damage is done to create the basis for a decubitus ulcer after as little as 2 h of immobility, a situation which may be difficult to avoid if the patient must undergo prolonged surgery or remain bedridden. Damage owing to pressure may also occur hours before the patient receives medical attention, especially if the patient falls or becomes immobilized owing to a vascular event. Several classification systems for decubitus ulcers have been described, based on where injury first occurs. The histologic progression of decubitus ulcers is a dynamic process involving several stages, each having characteristic histologic features. A team-focused approach integrating all aspects of care, including pressure relief, infection control, nutrition, and surgery, may improve healing rates. With accurate risk assessment and preventative care, we can hope to minimize complications and mortality owing to decubitus ulcers. [source] Dispersion of nanoscale BaTiO3 suspensions by a combination of chemical and mechanical grinding/mixing processesJOURNAL OF APPLIED POLYMER SCIENCE, Issue 3 2007Kuo-Liang Ying Abstract The colloidal stability of aqueous nanometer- and micrometer-scale barium titanate (BaTiO3) utilizing poly (methacrylic acid) (PMAA-Na) and polyacrylamide/(,- N,N -dimethyl- N -acryloyloxyethyl)ammonium ethanate (PDAAE) was investigated. In addition to chemical dispersants, the effects of mechanical milling using either conventional ball milling or nanogrinding/-mixing on the dispersion of BaTiO3 suspensions were also studied. Characterization of the particle size distribution (d50), viscosity, and morphology of BaTiO3 particles in the suspensions revealed that a sole chemical dispersant or mechanical milling was insufficient to achieve nanometer-scale dispersion. The best dispersion results were obtained with a combination of PMAA-Na dispersant and nanogrinding/-mixing, which could provide sufficient electronic repulsive force and shear force to disperse the 80-nm BaTiO3 powders uniformly in the aqueous suspension. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 [source] INTEGRATED STUDIES ON THE FRESHNESS OF RAINBOW TROUT (ONCORHYNCHUS MYKISS WALBAUM) POSTMORTEM DURING CHILLED AND FROZEN STORAGEJOURNAL OF FOOD BIOCHEMISTRY, Issue 3 2004CARMEL C. WILLS Rainbow trout were killed by two methods, asphyxiation and clubbing. The concentration of ATP in specimens of skeletal muscle taken immediately after death was significantly (P<0.01) higher in clubbed (4.41 ± 0.86 ,mol/g) than in asphyxiated (2.00 ± 0.69 ,mol/g) fish. The shear force (Warner-Bratzler) required to cut the muscle was higher (P<0.05) in clubbed (8.33 ± 0.61 N) than in asphyxiated (6.85 ± 0.98 N) fish. Changes in the concentration of adenine nucleotides and in shear force were measured at intervals during storage at 3C and - 30C. The K value was calculated and was found to be correlated inversely with changes in shear force, Torrymeter readings and sensory assessment. There were no significant differences in the concentrations of ATP and metabolites between muscle sites. There were no differences in shear force measurements between the locations sampled nor between muscle taken from the right and left sides of the fish. [source] DRYING METHODS AND QUALITY OF SHRIMP DRIED IN A JET-SPOUTED BED DRYERJOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2005RUNGTIP TAPANEYASIN ABSTRACT The objective of this study was to experimentally investigate the effects of various parameters, i.e., size of shrimp, level and pattern of inlet drying air temperature, on the drying kinetics and various quality attributes of dried shrimp viz. shrinkage, rehydration ability, texture and color during drying in a jet-spouted bed dryer. It was found that the use of a constant inlet air temperature of 100C yielded dried shrimp of the best quality in terms of low percentage of shrinkage, high percentage of rehydration, low maximum shear force and high value of redness compared to shrimp dried using other conditions. A simple mathematical model that enables prediction of the drying behavior of shrimp in a jet-spouted bed dryer has also been developed. [source] A SURVEY OF THE QUALITY OF SIX RETAIL BRANDS OF BONELESS, SKINLESS CHICKEN BREAST FILLETS OBTAINED FROM RETAIL SUPERMARKETS IN THE ATHENS, GEORGIA AREA,JOURNAL OF FOOD QUALITY, Issue 6 2007HONG ZHUANG ABSTRACT To assess the variation in quality of chicken breast fillets available from retail supermarkets, six brands of boneless, skinless fillets without additives were obtained from the fresh counter at grocery stores in Athens, GA, and the surrounding area during fall of 2005. The samples were stored at ,20C and subsequently cooked using a Henny Penny MCS-6 combi oven (Henny Penny Corp., Eaton, OH). Quality parameters of the fillets were measured on the cooked chicken breast fillets including cook yield, descriptive sensory flavor and texture profiling, and Warner,Bratzler (WB) shear force. Our results show that the average cook yield ranged from 78.1 to 80.9%, the average intensity of individual descriptive sensory characteristics was less than 5.4 in a 0,15 universal scale, and WB shear force values were less than 5.2 kg. There were no significant differences in the intensity among brands of all flavor attributes and the texture characteristics associated with moisture. However, significant differences were found among the brands for cook yield, mechanical properties of texture (including springiness, cohesiveness, hardness and chewiness) and WB shear force values. The variation of WB shear force measurements (coefficient of variation) depended on brand. These results indicate that differences exist in the quality and shear force consistency among market brands of boneless, skinless chicken breast fillets available in Athens, GA, and the surrounding area. PRACTICAL APPLICATIONS This study is the first survey reported to evaluate the quality of boneless, skinless chicken breast products without additives in U.S. retail market. This study supplies the evidence that the intensity of sensory quality is mild of cooked boneless, skinless chicken breast products and there are the differences in the quality among the different retail brands obtained by consumers. [source] QUALITY OF FROZEN SHRIMP THAWED BY RECIRCULATING AIR VERSUS WATER IMMERSIONJOURNAL OF FOOD QUALITY, Issue 1 2003C. S. LIN ABSTRACT The quality of shrimp thawed using a constant temperature thawing chamber compared with running water was studied. Shrimp thawed in room temperature air was used as the control. Shrimp thawed using the thawing chamber had lower drip loss, higher yield and moisture content than shrimp thawed by running water. However, the differences were not statistically significant. There were also no significant differences in press juice and shear force between control and shrimp thawed using either thawing method. Shrimp thawed using the thawing chamber had lower aerobic bacterial counts than either control or shrimp thawed using running water. Shrimp thawed using the thawing chamber did not exceed ,1C throughout the thawing experiment, and microbial growth during thawing was also avoided. Results indicated that the thawing chamber has potential for the foodservice industry to produce uniformly thawed products under sanitary conditions. [source] PHYSICAL AND SENSORY PROPERTIES OF MEATSTICK PRODUCTS AS AFFECTED BY FORMULATION AND DRYING: SENSORY-INSTRUMENTAL RELATIONSHIPSJOURNAL OF FOOD QUALITY, Issue 6 2002ANN BARRETT Shelf-stable meats are of interest to industry and are important in military ration development. Stability is commonly achieved through control of pH and water activity. However, reduction in moisture as a means to lower aw can significantly affect texture. Other ingredients, such as fat, can also potentially affect texture and possibly mitigate hardening due to lowered moisture. Meatsticks dried to three water activities, 0.88, 0.90, and 0.92, each from batters at three fat levels, 14, 17, and 21%, were produced, yielding products varying in both moisture and fat content. Products were subjected to mechanical and sensory testing and image and color analysis. Meatstick modulus, shear force, L* value, and percent of area of cut surfaces covered by separated fat were correlated with sensory assessments of interior hardness, hardness with skin, color, and visual fat, respectively. These parameters were significantly influenced by composition, particularly fat and protein contents and fat-protein interaction. [source] Effect of Actinidin on the Protein Solubility, Water Holding Capacity, Texture, Electrophoretic Pattern of Beef, and on the Quality Attributes of a Sausage ProductJOURNAL OF FOOD SCIENCE, Issue 3 2009M. Aminlari ABSTRACT:, The objective of this study was to study the effect of actinidin, a sulfhydryl protease from kiwi fruit, on the protein solubility (nitrogen solubility index [NSI]), water holding capacity (WHC), texture, and SDS,PAGE pattern of beef and to evaluate the effect of pretreatment of beef with actinidin on the quality attributes of a sausage product. Actinidin was partially purified by precipitation with ammonium sulfate, followed by DEAE-Sephadex column chromatography. Actinidin significantly (P < 0.05) increased NSI and WHC of beef; the highest NSI and WHC (approximately 20% and 8% increase, respectively) was observed when beef was incubated with 0.9 unit enzyme/g beef. Texture analysis indicated increased tenderization (10% decrease in shear force) when slices of cattle beef were treated with actinidin at 37 °C for 2 h. SDS,PAGE results indicated appearance of several low molecular weight bands (<10 kDa) after treating beef with different levels of actinidin for 30 or 60 min. Slight changes in protein band in the range of 100 to 120 kDa and 13 to 25 kDa were also observed. Use of actinidin-tenderized beef significantly improved emulsion stability, texture, and organoleptic properties of the sausage product. [source] Mortadella Sausage Formulations with Partial and Total Replacement of Beef and Pork Backfat with Mechanically Separated Meat from Spent Layer HensJOURNAL OF FOOD SCIENCE, Issue 3 2005Marco A. Trindade ABSTRACT: Mortadella sausages were formulated with 0%, 20%, 40%, 60%, 80%, and 100% mechanically separated layer hen meat (MSLM) replacing the beef and pork backfat as raw materials. Treatments were compared by determination of shear force, sensory acceptance, and stability during cold storage (microbial analysis, thiobarbituric acid-reactive substances [TBARS], color, and descriptive sensory analysis). Mortadella with higher MSLM presented lower shear force values. TBARS index and sensory rancidity were not affected. The greater the amounts of MSLM used, the paler was the pink color observed in the sensory evaluations and the lower were the CIE a* values. All treatments presented minimal increase in the microbiological counts evaluated during storage. The limiting factor in the acceptance of the product was the perception of bone particles in mortadella containing 60% or more MSLM. [source] The change in characteristics of microcrystalline cellulose during wet granulation using a high-shear mixerJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 5 2001Tatsuya Suzuki The objective of this study was to investigate the mechanism of hard granule formation and to demonstrate the applicability of X-ray diffraction methods for studying the polymeric pharmaceutical excipients. Using a high-shear mixer, microcrystalline cellulose (MCC) was granulated with water as the granulating liquid. The hardness of the MCC granules increased with granulation time and the amount of water added. The specific surface area measured by the N2 adsorption method was reduced during the process. Crystallite size of cellulose, calculated by Scherrer's equation adapted for wide angle X-ray diffraction method, decreased with granulation time and with increasing amounts of water added. Debye plots for X-ray small scattering patterns suggested that the average magnitude of the continuous solid region in MCC granules became significantly greater, whereas the specific surface area of the MCC granules, calculated from Debye plots, became smaller in comparison with that of intact MCC. These findings suggested that the long-chain structures in MCC were disrupted, resulting in smaller units with shorter chain lengths due to the strong shear force of the impeller. These smaller units then form a network within the granules. Thus, MCC granules are strengthened with longer granulation time and greater amounts of water, resulting in a more intricate network. The change in MCC chain length and physical structure can be experimentally detected using the small-angle X-ray scattering and wide-angle powder X-ray diffraction methods. [source] Fracture Resistances of Cast Metal and Ceramic Dowel and Core Restorations: A Pilot StudyJOURNAL OF PROSTHODONTICS, Issue 2 2005Emine Yalç, n DDS Purpose: The purpose of this study was to compare fracture strengths of teeth restored with cast metal and ceramic dowel and cores supporting all-ceramic crowns. Materials and Methods: Eighteen recently extracted teeth were randomly divided into 3 equal groups. Metal dowel and cores (MDC) were fabricated for 1 group using a base metal alloy, and served as the control. The other groups received In-Ceram Spinell® (ICS) and IPS Empress 2® (IPS) dowel and cores. IPS Empress 1 crowns were fabricated for all samples. Each tooth was subjected to a shear force at a crosshead speed of 2 mm/min on a universal testing machine until failure occurred. Results: The mean fracture strengths and standard deviations of MDC, ICS, and IPS restorations were 1101 N (361), 832 N (288), and 1137 N (367), respectively. The differences between groups were insignificant (p < 0.05). Fractures of the all-ceramic crowns were observed in the MDC group, whereas the failure of ceramic dowel and core restorations was associated with root fracture at the cervical region. Conclusions: Due to improved mechanical properties, In-Ceram Spinell® and IPS Empress 2® ceramic dowel and cores may be candidates for the restoration of endodontically treated anterior teeth. [source] RELATIONSHIP BETWEEN SENSORY AND TEXTURE MEASUREMENT OF JAMUN AND POSITIONING OF JAMUN SAMPLESJOURNAL OF SENSORY STUDIES, Issue 1 2002R. RAVI ABSTRACT Profilograms based on the quantitative descriptive analysis (QDA) of jamun using nine attributes were drawn for four market samples and ten samples prepared using various instant mixes available in the local market. The instrumental texture measurement of shear values were determined for all the samples. Correlations between sensory and instrumental texture measurement (shear force) were studied. The shear values were found to be correlated positively with softness, juiciness and milkiness. Further canonical discriminant analysis was run to position the samples in relation to others. The results indicated that samples M1, M2, M4, S3, S4, S6 and S10 group together in the same quadrant which represents desirable attributes of jamun viz, color, softness, juiciness, milkiness and overall quality. The jamuns from the instant mixes (S) can replace the control samples, traditionally prepared market samples (M) as they match the product profile very closely. [source] The role of cellular polysaccharides in the formation and stability of aerobic granulesLETTERS IN APPLIED MICROBIOLOGY, Issue 3 2001J.-H. Tay Aims:,This paper attempts to investigate the role of cellular polysaccharides in the formation and stability of aerobic granules. Methods and Results:,Three column sequential aerobic sludge blanket reactors (R1, R2 and R3) were operated at a superficial air upflow velocity of 0·3 cm s,1, 1·2 cm s,1 and 2·4 cm s,1, respectively. Aerobic granules appeared at cycle 42 in R2 and R3 with a mean size of 0·37 mm in R2 and 0·35 mm in R3, however, aerobic granulation was not observed in R1. After the formation of aerobic granules, the sludge volume index (SVI) decreased to 55 ml g,1 in R2 and 46 ml g,1 in R3. Aerobic granulation was concurrent with a sharp increase of cellular polysaccharides normalized to cellular proteins, which increased from 5·7 to 13·0 mg per mg proteins in R2, and 7·5,13·9 mg per mg protein in R3. The content of polysaccharides in aerobic granules was 2,3 times higher than that in the bioflocci cultivated in R1. The disappearance of aerobic granules in R2 was tightly coupled to a drop in cellular polysaccharides. After the reappearance of bioflocci in R2, the content of cellular polysaccharides were found to be restored to the level observed in R1. Conclusions:,It appears that the production of cellular polysaccharides could be stimulated by hydrodynamic shear force and contributes to the formation and stability of aerobic granules. Significance and Impact of the Study:,It is expected that this study would provide useful information for better understanding the mechanisms of aerobic granulation. [source] Effect of Perpendicular Shear Force on the Interfacial Morphology of Reactive Polymer BilayerMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 7 2008Hwang Yong Kim Abstract We investigated the effect of shear forces perpendicular to the interface on the interfacial morphology of a reactive bilayer. It was observed that the perpendicular shear force greatly enhanced the roughness of the interface compared with parallel shear force. The main role of in situ formed graft copolymers is not to increase greatly the roughness of the interface, but to stabilize the interfacial morphology. We also observed that microemuslsions were observed at both the PMMA and PS layers, which is distinctly different from the situation obtained under parallel shear force (or without shear) that the microemlusions were seen in only the PMMA layer. [source] Phase Separation and Organisation of Colloidal Spheres Suspended in Sheared Lyotropic Liquid-Crystalline PolymersMACROMOLECULAR RAPID COMMUNICATIONS, Issue 11 2005Shanju Zhang Abstract Summary: Organisation behaviours of spherical particles suspended in sheared, lyotropic, liquid-crystalline polymer solutions have been investigated using polarizing optical microscopy. We find that in a nematic phase the particles phase separate and adopt anisotropic chain-like structures along the director. An earring defect is observed around a single particle whereas a cross or strings defect between neighbouring particles is found to serve as a repulsive barrier to prevent the particles from contacting each other. A theoretical analysis is presented to explain this new phenomenon. An optical micrograph of 0.01 wt.-% glass spheres suspended in a nematic solution of 40 wt.-% ethyl cellulose in chloroform under an external shear force. [source] Compatibilizing effect of ethylene,propylene,diene grafted maleic anhydride terpolymer on the blend of polyamide 66 and thermal liquid crystalline polymerPOLYMER COMPOSITES, Issue 6 2006Qunfeng Yue Polyamide 66,thermal liquid crystalline polymer (PA66/TLCP) composites containing 10 wt% TLCP was compatibilized by ethylene,propylene,diene-grafted maleic anhydride terpolymer (MAH- g -EPDM). The blending was performed on a twin-screw extrusion, followed by an injection molding. The rheological, dynamic mechanical analysis (DMA), thermal, mechanical properties, as well as the morphology and FTIR spectra, of the blends were investigated and discussed. Rheological, DMA, and FTIR spectra results showed that MAH- g -EPDM is an effective compatibilizer for PA66/TLCP blends. The mechanical test indicated that the tensile strength, tensile elongation, and the bending strength of the blends were improved with the increase of the content of MAH- g -EPDM, which implied that the blends probably have a great frictional shear force, resulting from strong adhesion at the interface between the matrix and the dispersion phase; while the bending modulus was weakened with the increase of MAH- g -EPDM content, which is attributed to the development of the crystalline phase of PA66 hampered by adding MAH- g -EPDM. POLYM. COMPOS., 27:608,613, 2006. © 2006 Society of Plastics Engineers [source] Relationships among calpastatin single nucleotide polymorphisms, calpastatin expression and tenderness in pork longissimus,ANIMAL GENETICS, Issue 5 2009A. K. Lindholm-Perry Summary Genome scans in the pig have identified a region on chromosome 2 (SSC2) associated with tenderness. Calpastatin is a likely positional candidate gene in this region because of its inhibitory role in the calpain system that is involved in postmortem tenderization. Novel single nucleotide polymorphisms (SNP) in calpastatin were identified and used to genotype a population (n = 1042) of Duroc,Landrace,Yorkshire swine for association with longissimus lumborum slice shear force (SSF) measured at days 7 and 14 postmortem. Three genetic markers residing in the calpastatin gene were significantly associated with SSF (P < 0.0005). Haplotypes constructed from markers in the calpastatin gene were significantly associated with SSF (F -ratio = 3.93; P -value = 0.002). The levels of normalized mRNA expression of calpastatin in the longissimus lumborum of 162 animals also were evaluated by real-time RT-PCR and were associated with the genotype of the most significant marker for SSF (P < 0.02). This evidence suggests that the causative variation alters expression of calpastatin, thus affecting tenderness. In summary, these data provide evidence of several significant, publicly available SNP markers associated with SSF that may be useful to the swine industry for marker assisted selection of animals that have more tender meat. [source] Effects of transportation during the hot season, breed and electrical stimulation on histochemical and meat quality characteristics of goat longissimus muscleANIMAL SCIENCE JOURNAL, Issue 3 2010Isam T. KADIM ABSTRACT The effects of transportation and electrical stimulation (90 V) on physiological, histochemical and meat quality characteristics of two breeds of Omani goats were assessed. Twenty 1-year-old male goats from each breed (Batina and Dhofari) were divided into two groups: 3 h transported during the hot season (42°C day time temperature) and non-transported. Animals were blood-sampled before loading and prior to slaughter. Electrical stimulation was applied 20 min postmortem to 50% randomly selected carcasses of both breeds. Temperature and pH decline of the Longissimus was monitored. Ultimate pH, shear force, sarcomere length, myofibrillar fragmentation index, expressed juice, cooking loss and colour were measured from samples of Longissimus dorsi muscles. Electrical stimulation and transportation had a significant effect on most biochemical and meat quality characteristics of Longissimus dorsi. The transported goats had higher plasma cortisol (P < 0.01), adrenaline, nor-adrenaline and dopamine concentrations (P < 0.05) than non-transported goats. Electrical stimulation resulted in a significantly (P < 0.05) more rapid muscle pH fall during the first 12 h after slaughter. Muscles from electrically-stimulated carcasses had significantly (P < 0.05) longer sarcomeres, lower shear force value, a lighter colour (higher L* value), higher expressed juice and myofibrillar fragmentation index than those from non-stimulated ones. Meat from transported goats had significantly higher pH, expressed juice and shear force, but contained significantly lower sarcomere length and L* values than non-transported goats. The proportion of the myosin ATPase staining did not change as a function of stimulation, transportation or breed. These results indicated that subjecting goats to transportation for 3 h under high ambient temperatures can generate major physiological and muscle metabolism responses. Electrical stimulation improved quality characteristics of meat from both groups. This indicates that electrical stimulation may reduce detrimental effects of transportation on meat quality of Omani goats. [source] Changes in water-holding capacity and textural properties of chicken gizzard stored at 4°CANIMAL SCIENCE JOURNAL, Issue 3 2010Yoshito TOMISAKA ABSTRACT The water-holding capacity (WHC), and toughness (shear force) of chicken gizzard were evaluated during postmortem storage for 4.5, 7, 12, 24, 48, 72 and 96 h at 4°C. Degradation of the cytoskeletal proteins desmin, talin and vinculin were monitored by sodium dodecyl sulfate , polyacrylamide gel electrophoresis and Western blotting during the same designated storage period. The WHC of the gizzards decreased significantly from 12 h to 72 h of storage, but by 96 h the WHC was restored to the level measured after storage for 12 h. The shear force value of the gizzards increased rapidly until 12 h and then decreased until 24 h, with a further slight decrease by 48 h. Degradation products of desmin, talin and vinculin appeared at 96 h, 12 h and 48 h postmortem, respectively. The intensity of immunolabeling for desmin, talin and vinculin after storage for 96 h decreased to 51%, 25% and 52% of the initial value. The appearance of desmin degradation products was accompanied by an increase in WHC. This suggests that the postmortem degradation of desmin is involved in the increase of WHC in chicken gizzard during storage at 4°C, and talin and vinculin may be involved. [source] Textural properties of raw Atlantic salmon (Salmo salar) fillets measured by different methods in comparison to expressible moistureAQUACULTURE NUTRITION, Issue 2 2001Jonsson Textural properties of fresh Atlantic salmon (Salmo salar) fillets were measured on seven locations along the fillet by four different instrumental methods, and were correlated to expressible moisture. Two methods were based on puncturing, either by using a flat ended cylinder, measuring hardness at different distances into the fillet and the first fracture (yield point) of the muscle fibres, or by a non-destructive method using a spherical probe to measure the hardness of the fillet. The other two methods were based on Kramer shear-compression cell or Warner-Bratzler shear cell, by shearing the fillet with blades, measuring the shear force (toughness). The ability to separate textural properties in different muscle segments by using these four methods were compared. The expressible moisture, was determined by using the filter paper method by compression. Hardness and shear force of the fillets generally increased from the anterior to the posterior part of the fillet while the necessary force applied to map the yield point decreased towards the tail section. The results from the present study indicated that the puncture method with the spherical probe and the shearing device by Warner-Bratzler were better suited for measuring differences in the textural properties between different parts of raw salmon fillet, than the flat ended cylinder and Kramer shear compression cell. The expressible moisture, varying between 1.8 and 2.7%, showed a significant (P < 0.05) linear correlation with the spherical probe texture measurements (r=0.83) and the Kramer shear compression cell (r=0.77). [source] | |||||||||||||||||||||||||