8,126 research outputs found
Stress-strain-time Relationship Of Queenston Shale (volumes I And Ii)
For the design and construction of underground structures in swelling rocks, it is important to understand the time-dependent deformation behaviour and develop the stress-strain-time relationships for the analysis of the rock-structure-time interaction problem. This thesis deals with these two areas of research.;Four new test apparatus were designed and constructed for the measurement of time-dependent deformation in three orthogonal directions for the study of the swelling behaviour of the Queenston shale from Niagara Falls, Ontario. Using the new and existing test apparatus, six types of time-dependent deformation tests were performed on samples prepared from oriented rock cores of the Queenston shale. In addition, a specially designed test program was carried out to investigate the mechanism of the swelling of the shales.;The general stress-strain-time relationships in three dimension were formulated using the results of time-dependent deformation tests. A new methodology was developed and found to be capable of taking into account the non-linear swelling deformation response under uniaxial and biaxial stress conditions.;The main conclusions that have emerged from this course of the study are: (1) The time-dependent deformation behaviour of the shale is essentially cross-anisotropic with higher swelling potential in the vertical direction and is strongly stress-dependent. (2) The necessary and sufficient conditions for swelling to occur due to unloading are (a) the relief of initial stress, (b) the accessibility to water and (c) an outward salt concentration gradient from rock to ambient fluid. (3) The general stress-strain-time relationships developed are found to be adequate for the prediction of the non-linear swelling deformation response of the Queenston shale under applied uniaxial and biaxial states of stresses
Reconstitution and Characterization of Human Endogenous Retrovirus-K
Retroviruses are a family of clinically significant and scientifically fascinating viruses that infect a wide array of organisms from all vertebrate classes. The two hallmark events in the life cycle of retroviruses are the reverse transcription of the single stranded RNA (ssRNA) genome generating a double stranded DNA (dsDNA) and the integration of this dsDNA into the host genome. Because integration is irreversible and the infected cells are usually difficult to target for elimination in the host, the infection is generally permanent. HIV-1, the most important and well-studied member of all retroviruses, is the causative agent of acquired immune deficiency syndrome (AIDS) for which no vaccine or cure is known. Since recognition of the AIDS epidemic, around 25 million people have died from HIV-1 related causes, including 2 million in 2007. Currently, 33 million people are believed to be living with the virus, with most of these people living in sub-Saharan Africa, where 67% of all infected people reside and 75% of AIDS deaths occurred in 2007. When retroviruses infect germ cells or germ cell progenitors, the virus can become endogenized. These viruses, called endogenous retroviruses (ERV), make up more than 8% of the human genome. The integrated virus will be present in the genome of all cells of the individual derived from the infected germ cell, and be passed on to progeny in a Mendelian manner to following generations. Both chance and the insertion’s effect on the fitness of the host can determine the allelic frequency in the population. Hence, elements which produce large quantities of viral proteins and progeny or elements that insert into a necessary gene will likely reduce the fitness of the host and as an allele will be negatively selected in the host population. Currently, there is no known replication competent HERV, as most proviruses are filled with deletions and premature stop codons. However, one family of Class II HERV, HERV-K(HML-2), seems to have been replicating until recently. The HERV-K(HML-2) family includes human specific members and elements that are polymorphic in the human population, suggesting replication since the divergence of humans from chimpanzees 6 million years ago and potentially more recently as well. In this body of work, the problem of the lack of a replication competent virus sequence is circumvented by deducing a consensus sequence from the youngest set of HERV proviruses. Named HERV-KCON, we find that many of its components are functional individually and together enable infection of target cells in a single-cycle infection system. Using this system, we have characterized the previously unknown aspects of HERV-K(HML-2) life cycle, such as location of assembly and budding, dependency on cell replication, and more extensively, its ntegration site preference. HERV-KCON’s interaction with current anti-retroviral host proteins is accessed, and evidence of the same interaction occurring in vivo is presented in the context of APOBEC3G
CP violating dimuon charge asymmetry in general left-right models
The recently measured charge asymmetry of like-sign dimuon events by the D0
collaboration at Tevatron shows the 3.9 \sigma\ deviation from the standard
model prediction. In order to solve this mismatch, we investigate the
right-handed current contributions to and
mixings which are the major source of the like-sign dimuon events in production in general left-right models without imposing manifest or
pseudo-manifest left-right symmetry. We find the allowed region of new physics
parameters satisfying the current experimental data.Comment: 9 pages, 4 figure
Review on Blueprint of Designing Anti-Wetting Polymeric Membrane Surfaces for Enhanced Membrane Distillation Performance
Recently, membrane distillation (MD) has emerged as a versatile technology for treating saline water and industrial wastewater. However, the long-term use of MD wets the polymeric membrane and prevents the membrane from working as a semi-permeable barrier. Currently, the concept of antiwetting interfaces has been utilized for reducing the wetting issue of MD. This review paper discusses the fundamentals and roles of surface energy and hierarchical structures on both the hydrophobic characteristics and wetting tolerance of MD membranes. Designing stable antiwetting interfaces with their basic working principle is illustrated with high scientific discussions. The capability of antiwetting surfaces in terms of their self-cleaning properties has also been demonstrated. This comprehensive review paper can be utilized as the fundamental basis for developing antiwetting surfaces to minimize fouling, as well as the wetting issue in the MD process
Excavation Behaviour of Soft Marine Clay Deposit in South Korea
In this paper, it is demonstrated that the shear strength of soil around jet grouting pile may be increased with the elapsed curing time of grouting cement. Because soil around pile initially experiences the disturbance due to the jet grouting work process, the soil gains the strength as grouting cement is cured and the soil is stabilized. In addition, excavation behaviour of marine clay at sheet pile wall and strut excavation site is analyzed using measured data from inclinometers, load cells, and strain gauges. The time to install supporting system and not only depth to but also area of excavation are very important factors for analyzing excavation behavior of soft marine clay
Biomechanical Effects of Men\u27s Dress Shoes Made with Eco-Friendly Materials
The purpose of this study was to evaluate wearers\u27 performance in men\u27s leather shoes comparing with sustainable shoes using an experimental research design. It was hypothesized that there were no differences in kinetic and kinematic parameters of gait within lower extremity of participants wearing the leather shoes and sustainable shoes while performing the following three conditions: walking on flat ground, ascending, and descending stairs. A total of 37 human subjects were used for the data analyses. For kinetics, no statistically significant mean differences between the two shoes during descending stairs was identified. For kinematics, no statistically significant differences for peak angles of hips, knees, and ankles were found between the two shoes during ascending and descending stairs. The findings of this study confirm the possibility for multi-layered cellulosic material to use as an alternative leather when making sustainable men’s dress shoes in terms of kinematics and kinetics
Multi-layered Cellulosic Material as a Leather Alternate in the Footwear Industry
We aimed to develop a biodegradable and compostable material that could be used as a leather alternate for the footwear industry, which leads to reduce the negative impact of this industry to the environment. This experimental study was conducted to develop a multi-layered cellulosic material (cellulosic fiber mat + denim + hemp) and examine its material properties – thermal comfort, air permeability, tensile strength, and wettability – compared with those of two-layered leather (calf skin + pig skin) often used when making shoes. We hypothesized that these two materials would have similar properties. This study presented the effectiveness of a multi-layered cellulosic material to be used as a leather alternate when developing shoes. The results also provided a better understanding of the influence of a multi-layered cellulosic material on the wearers\u27 thermal comfort. Further research is suggested identifying solutions to reduce water absorbency of this multi-layered cellulosic material
RETHINK II: Kombucha Shoes for Scarlett and Rhett
We challenged ourselves to rethink what constitutes sustainable consumer products in a world of increasingly stressed natural resources. We explored the innovative way to develop renewable materials, leather-like nonwoven fabrics, which can be used for apparel and footwear products for the betterment of people and the planet. The cellulose fiber mats formed by bacteria and yeast in fermenting green tea can be produced without any synthetic process or chemical materials. Our kombucha shoes can be an alternate future where we move to a cradle-to-cradle system, instead of relying on materials derived from unsustainable sources. The outcome of our innovative design efforts is presented by creating aesthetically pleasing, biodegradable shoes for Scarlett and Rhett, leading characters from Gone with the Wind, one of the most famous American fiction bestsellers published in the 1930s. RETHINK II design provides a promising future of this biodegradable material as an alternate future suitable for footwear
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