scholarly journals Morphostructural Characterization of the Black Creole Goat Raised in Central Mexico, a Currently Threatened Zoogenetic Resource

Animals ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 459 ◽  
Author(s):  
Juan Carlos Silva-Jarquin ◽  
Sergio Iván Román-Ponce ◽  
Marina Durán-Aguilar ◽  
Héctor Raymundo Vera-Ávila ◽  
Víctor Hugo Cambrón-Sandoval ◽  
...  
Keyword(s):  
Euclidean Distance ◽  
Descriptive Statistics ◽  
Hierarchical Analysis ◽  
Harmonic Model ◽  
The Matrix ◽  
Components Analysis ◽  
Creole Goat ◽  
Positive Correlations ◽  
The Relationship

In order to evaluate the morphostructural variability of the Black Creole goat (BCG), the present study was carried out in a population of 226 animals from eight localities and 14 morphometric variables were taken. Descriptive statistics for the variables were obtained and 10 of these presented variation coefficients of less than 10%. The degree of harmony in the morphology of the population was determined by the number of positive correlations with significant differences (p < 0.05), including a correlation test using Spearman’s method. In order to reduce the matrix of variables, a principal components analysis was performed, and it was evaluated based on Kaiser’s criteria (eigenvalue > 1). Finally, a hierarchical analysis of conglomerates using Ward’s method was performed using the Euclidean distance to evaluate the distances among localities. Morphometric variables were also included to visualize the relationship among the localities and their average per variable. The results showed that the animals evaluated presented a certain degree of homogeneity and maintained a highly harmonic model. The BCG population showed a high aptitude for milk production, which confirmed the zootechnical purpose of the breed. The BCG populations evaluated maintain similar morphostructural profiles specific to them that can distinguish this population from other animal breeds.

scholarly journals Characterization of percolation behavior in conductor–dielectric 0-3 composites

2014 ◽  
Vol 04 (04) ◽  
pp. 1450035 ◽  
Author(s):  
Lin Zhang ◽  
Patrick Bass ◽  
Zhi-Min Dang ◽  
Z.-Y. Cheng
Keyword(s):  
Dielectric Constant ◽  
Percolation Threshold ◽  
Frequency Dependence ◽  
Experimental Results ◽  
Effective Dielectric Constant ◽  
Filler Concentration ◽  
Percolation Behavior ◽  
The Matrix ◽  
The Relationship

The equation ε eff ∝ (ϕc - ϕ)-s which shows the relationship between effective dielectric constant (εeff) and the filler concentration (φ), is widely used to determine the percolation behavior and obtain parameters, such as percolation threshold φc and the power constant s in conductor–dielectric composites (CDCs). Six different systems of CDCs were used to check the expression by fitting experimental results. It is found that the equation can fit the experimental results at any frequency. However, it is found that the fitting constants do not reflect the real percolation behavior of the composites. It is found that the dielectric constant is strongly dependent on the frequency, which is mainly due to the fact that the frequency dependence of the dielectric constant for the composites close to φc is almost independent of the matrix.

scholarly journals Influences of Participation Motivation and Satisfaction of Nursing Students on Continuance Willingness of Voluntary Activities

2018 ◽  
Vol 24 (4) ◽  
pp. 415-423
Author(s):  
Ya Ki Yang
Keyword(s):  
Nursing Students ◽  
Correlation Coefficient ◽  
Pearson Correlation ◽  
Educational Programs ◽  
Descriptive Statistics ◽  
Pearson Correlation Coefficient ◽  
Factors Influencing ◽  
Participation Motivation ◽  
Positive Correlations ◽  
The Relationship

Purpose: This study was done to examine the relationship between participation motivation, satisfaction and continuance willingness of voluntary activities of nursing students, and to identify factors influencing continuance willingness of voluntary activities. Methods: The research participants were 175 nursing students in the nursing departments of 3 universities located in G city and J province in Korea. Data were analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation coefficient and multiple regression. Results: Participants' scores for participation motivation, satisfaction and continuance willingness of voluntary activities were $3.24{pm}0.76$, $3.11{pm}0.83$ and $3.03{pm}0.85$ respectively. Participation motivation and satisfaction of voluntary activities had positive correlations. Satisfaction and continuance willingness of voluntary activities had positive correlations. Factors influencing nursing students' continuance willingness of voluntary activities included participation motivation and satisfaction of voluntary activities. And these variables explained 74% of the variance in continuance willingness of voluntary activities. Conclusion: The findings show that development and application of educational programs to increase participation motivation and satisfaction of voluntary activities are important and will improve nursing students' continuance willingness of voluntary activities.

scholarly journals Managers’ Conceptions and Their Effects on the Perception of Employees with Disabilities

2020 ◽  
Vol 17 (19) ◽  
pp. 7039
Author(s):  
Antônio Luiz Marques ◽  
Marina Romeo ◽  
Marjorye Matalinares ◽  
Montserrat Yepes-Baldó
Keyword(s):  
Human Resources ◽  
Social Problem ◽  
Training Needs ◽  
Descriptive Statistics ◽  
Hierarchical Analysis ◽  
Persons With Disabilities ◽  
Employees With Disabilities ◽  
Performance Bond ◽  
The Relationship ◽  
And Training

The research aimed to identify managers’ conceptions of disability and the relationship that was established between these conceptions and their perception of the persons with disabilities (PWD) performance, bond, benefits of hiring, and training needs. 257 managers answered a questionnaire in order to identify conceptions of disability in organizations. Descriptive statistics, factorial analysis, and hierarchical analysis of grouping were performed while using IBM Statistic 20.0.0. The results show that managers who have the spiritual and the conception based on inclusion perceive the insertion of PWD as beneficial to the organization. Those who conceive disability as a question of normality perceive the PWD performance as inferior to those without disabilities, which implies that PWDs should be segregated; and, the managers who perceive disability as a social problem are likely to place PWDs in the workplace according to their potential. The results can be fruitfully used by managers, human resources’ professionals, academics, and the society to promote inclusion.

Filament Fragmentation Phenomena

1989 ◽  
Vol 170 ◽  
Author(s):  
Juan C. Figueroa ◽  
Linda S. Schadler ◽  
Campbell Laird
Keyword(s):  
Strain Energy ◽  
Stress Transfer ◽  
Fiber Surface ◽  
Yield Information ◽  
The Matrix ◽  
Two Parameters ◽  
The Relationship

AbstractThe effect of fiber surface treatments on the relationship between the tensile strength of a filament and the shear strength of its interphase is one of the central issues facing composite materials technologists today. We demonstrate here that analysis of fragmentation phenomena in monofilament composites can simultaneously yield information about these two parameters. Characterization of shear stress transfer zones in non-critical fragments has led us to the determination of interphase strength.A phenomenological treatment that highlights the role of the matrix in the fragmentation process is presented here. This analysis considers issues such as the strain energy exchange between a failing fiber and the matrix, as well as interphase relaxation due to the viscoelastic nature of the matrix. Our observations of the fragmentation phenomena in AU4/polycarbonate monofilament composites indicate that the fiber/matrix interaction in this system is governed by micromechanical locking.

scholarly journals Sterility-mutability correlation: On the correlation between sterility and mutability during P-M hybrid dysgenesis in Drosophila melanogaster

1987 ◽  
Vol 50 (1) ◽  
pp. 73-76 ◽  
Author(s):  
Gail M. Simmons
Keyword(s):  
Drosophila Melanogaster ◽  
Natural Population ◽  
Gonadal Dysgenesis ◽  
Hybrid Dysgenesis ◽  
Positive Correlations ◽  
The Relationship

SummaryTwelve isogenic X chromosome lines from a single natural population of Drosophila melanogaster were tested for their potential to induce gonadal dysgenesis and singed-weak mutability in P-M hybrid dysgenesis. The correlation between sterility and mutability was significantly positive for Cross A, confirming the results reported by Engels (1984) and Kocur, Drier & Simmons (1986). In Cross A* cytotype tests, however, two of the lines gave strikingly different results when measured by the gonadal dysgenesis test as compared to the singed-weak test. Positive correlations between traits within a given line were generally not observed. The results suggest that the relationship between gonadal dysgenesis production and the mobilization of P elements in singed-weak mutability is more complicated than that proposed by Engels (1984). The two phenomena may be separable under certain conditions. Neither test can be taken as an adequate characterization of the hybrid dysgenesis ‘profile’ of a line of flies.

Synthesis and Characterization of TiO2 Reinforced Al6061 Composites

2017 ◽  
Vol 26 (1) ◽  
pp. 096369351702600 ◽  
Author(s):  
G B Veeresh Kumar ◽  
P S Shivakumar Gouda ◽  
R Pramod ◽  
C S P Rao
Keyword(s):  
Aluminum Matrix ◽  
Tribological Characteristics ◽  
Dry Sliding Wear ◽  
Aluminum Matrix Composites ◽  
Matrix Composites ◽  
Mechanical Characterisation ◽  
The Matrix ◽  
Mechanical And Tribological Characteristics ◽  
The Relationship

This article presents the investigative work carried out to study the relationship between the physical, mechanical and tribological characteristics of aluminum matrix composites reinforced with Titanium dioxide (TiO2). The powder metallurgy route of production was followed to produce the composites (Al6061 containing 3 wt% TiO2). The composites were subjected to sequences of physical, mechanical and tribological investigations. The outputs of the experiments done indicate that the increase in TiO2 fillers increase the density of the composite and the values accepted by the rule of mixtures. The result of mechanical characterisation of Al6061-TiO2 composites was noticed to increase significantly with higher TiO2 content in the matrix, with loss in ductility. The dry sliding wear studies of Al6061-TiO2 composite showed greater wear resistance than Al6061 matrix and the composite containing higher filler content displayed the superior physical, mechanical and tribological characteristics.

scholarly journals Assessing the Correlation between Skeletal and Corresponding Soft-Tissue Equivalents to Determine the Relationship between CBCT Skeletal/Dental Dimensions and 3D Radiographic Soft-Tissue Equivalents

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Da In Kim ◽  
Manuel O. Lagravère
Keyword(s):  
Standard Deviation ◽  
Measurement Error ◽  
Soft Tissue ◽  
Euclidean Distance ◽  
Descriptive Statistics ◽  
Spinal Level ◽  
Distance Measurements ◽  
Tissue Equivalents ◽  
Left Corner ◽  
The Relationship

Objective. Compare measurements of skeletal and dental areas on the CBCT to the corresponding soft-tissue measures taken from a 3D Facial Scanner. Methods. 30 patients with CBCT and 3D Facial scanner photos were selected from the orthodontic program database. 30 different distance measurements were obtained from CBCT and facial scan. OrthoInsight software was used to obtain the measurements from the facial scan images, and AVIZO software was used for corresponding CBCT landmarks. The Euclidean distance formula was used to determine the distances for the corresponding x, y, and z coordinates of the CBCT. Reliability for CBCT and Facial Scanner was completed by calculating 30 distances for 10 patients, 3 times. Once reliability was determined, all 30 distances were calculated once for CBCT and facial scanner on each patient and descriptive statistics and paired t-test were applied. Results. All distances measured presented excellent reliability, the lowest one being the left eye width for the facial scanner (ICC 0.847). The landmark with the highest mean error on the CBCT was 2.0 ± 1.6 mm on the z-axis for the spinal level landmark. The Facial Scanner’s largest mean measurement error was 1.5 ± 0.9 mm for the distance of the left corner of the mouth to gonion. All data except width between outer eye corners were statistically significant (p<0.05). The average differences between facial scan and CBCT measurements ranged between 0.77 mm (left canine to cheekbone) to 26.94 mm (left subnasale to gonion) and are thus comparable. All measurements show a reasonable standard deviation between 2.57 mm (left eye width) to 9.91 mm (left gnathion to EAM). Conclusion. Distances obtained from CBCT and facial scan present mild differences giving the perspective of a relationship between them. Understanding this difference and relationship can make it plausible to expect certain underlying skeletal distances under soft-tissue structures.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

TEM characterization of reaction zone in a SiC fiber-reinforced titanium alloy

1988 ◽  
Vol 46 ◽  
pp. 738-739
Author(s):  
G. Das ◽  
R. E. Omlor
Keyword(s):  
Titanium Alloys ◽  
Reaction Zone ◽  
Carbon Layer ◽  
Fiber Reinforced ◽  
Reaction Products ◽  
Sic Fibers ◽  
Sic Fiber ◽  
The Matrix ◽  
Immense Potential

Fiber reinforced titanium alloys hold immense potential for applications in the aerospace industry. However, chemical reaction between the fibers and the titanium alloys at fabrication temperatures leads to the formation of brittle reaction products which limits their development. In the present study, coated SiC fibers have been used to evaluate the effects of surface coating on the reaction zone in the SiC/IMI829 system.IMI829 (Ti-5.5A1-3.5Sn-3.0Zr-0.3Mo-1Nb-0.3Si), a near alpha alloy, in the form of PREP powder (-35 mesh), was used a茸 the matrix. CVD grown AVCO SCS-6 SiC fibers were used as discontinuous reinforcements. These fibers of 142μm diameter contained an overlayer with high Si/C ratio on top of an amorphous carbon layer, the thickness of the coating being ∽ 1μm. SCS-6 fibers, broken into ∽ 2mm lengths, were mixed with IMI829 powder (representing < 0.1vol%) and the mixture was consolidated by HIP'ing at 871°C/0. 28GPa/4h.

Microstructural Characterization of Au-Ge-Ni based ohmic contacts to GaAs/AlGaAs modfet device

1987 ◽  
Vol 45 ◽  
pp. 326-327
Author(s):  
A.K. Rai ◽  
A.K. Petford-Long ◽  
A. Ezis ◽  
D.W. Langer
Keyword(s):  
Contact Resistance ◽  
Ohmic Contact ◽  
Ohmic Contacts ◽  
Microstructural Characterization ◽  
Almost Everywhere ◽  
Spacer Layer ◽  
Good Contact ◽  
The Relationship ◽  
Lower Contact

Considerable amount of work has been done in studying the relationship between the contact resistance and the microstructure of the Au-Ge-Ni based ohmic contacts to n-GaAs. It has been found that the lower contact resistivity is due to the presence of Ge rich and Au free regions (good contact area) in contact with GaAs. Thus in order to obtain an ohmic contact with lower contact resistance one should obtain a uniformly alloyed region of good contact areas almost everywhere. This can possibly be accomplished by utilizing various alloying schemes. In this work microstructural characterization, employing TEM techniques, of the sequentially deposited Au-Ge-Ni based ohmic contact to the MODFET device is presented.The substrate used in the present work consists of 1 μm thick buffer layer of GaAs grown on a semi-insulating GaAs substrate followed by a 25 Å spacer layer of undoped AlGaAs.

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