1,350 research outputs found
An innovative engineering design model by the aid of TRIZ methodology and CAE technology.
This thesis presents research that advocates process, methods and new technology for performance related robustness improvements in product development. Rapid advances in technology in recent years have set new demands on product development. As a consequence, an increasing variety of products are built on heterogeneous technologies. Specialists from different engineering disciplines must cooperate to a greater extent than before in order to understand the products. Increased cooperation and heterogeneous technologies in products set high demands on rapid product development models in order to deliver products of high quality in short lead time, at low cost. One of the most important tasks in robust design is to select an appropriate system output response. The quality of this selection will greatly affect the effectiveness of the robust design project. Currently, this selection process is more like art than science. By using TRIZ Design principle, several new approaches to enhance robust design are developed. These approaches enable us to select the appropriate system output response in a systematic fashion. The approach developed in this paper was successfully applied and verified in two case studies in two different major automotive companies. This research consists of theory development, mainly in the field of engineering design, TRIZ and CAE. The research in the papers provides: (1) An approach to problem solving by combining design object analysis with TRIZ and FEA; (2) Two case studies carried out with the researcher actively taking part in practical problem solving. (Abstract shortened by UMI.) Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2005 .Y82. Source: Masters Abstracts International, Volume: 44-03, page: 1477. Thesis (M.A.Sc.)--University of Windsor (Canada), 2005
Entanglement area law for 1D gauge theories and bosonic systems
We prove an entanglement area law for a class of 1D quantum systems involving
infinite-dimensional local Hilbert spaces. This class of quantum systems
include bosonic models such as the Hubbard-Holstein model, and both U(1) and
SU(2) lattice gauge theories in one spatial dimension. Our proof relies on new
results concerning the robustness of the ground state and spectral gap to the
truncation of Hilbert space, applied within the approximate ground state
projector (AGSP) framework from previous work. In establishing this area law,
we develop a system-size independent bound on the expectation value of local
observables for Hamiltonians without translation symmetry, which may be of
separate interest. Our result provides theoretical justification for using
tensor network methods to study the ground state properties of quantum systems
with infinite local degrees of freedom
Modeling individual development plans, mentoring support, and career preparedness relationships among Doctor of Philosophy (Ph.D.) trainees in the life sciences
Background: As greater career development support for doctoral students and postdoctoral researchers has been emphasized, the individual development plan (IDP) has become a recommended mentoring tool. However, little is known about the effect of IDPs on mentoring and career development. This study proposed two conceptual models to examine the interrelationships among the use of IDPs, mentoring support, and career preparedness with a diverse sample of doctoral students and postdoctoral researchers in the life sciences.
Methods: The data leveraged for this study was collected over a three-month period, March 2016 to June 2016, as part of a cross-sectional, online survey. The survey was distributed through social media and direct email to participants enrolled in life/biological/medical or physical/applied doctoral programs at U.S. institutions. To test the proposed conceptual models, this study employed the design-based multilevel structural equation modeling.
Results: The analytic sample comprised 660 doctoral students and postdoctoral researchers in the life sciences from 91 institutions. The results suggested that 1) using the IDP could enhance mentoring support and career preparedness of doctoral students and postdoctoral researchers; 2) greater mentoring support and career preparedness would motivate mentees to continue utilizing the IDP with their principal investigator (PI) or advisor; and 3) females, postdoctoral researchers, and international scholars might need more support throughout the mentoring and career development process.
Conclusions: This research offered empirical evidence for how an IDP, mentorship, and career preparedness interact. Findings revealed the IDP enhances mentoring support and career preparedness, as well as mentoring support and career preparedness predict IDP use. We conclude the IDP is an important mentorship tool that enhances trainees’ overall career preparation
Recommended from our members
Evaluating the placement of PIT tags in tropical river fishes: a case study involving two Mekong River species
Fish communities are becoming increasingly threatened in many tropical river-floodplain systems due to the construction of dams and other physical barriers. Efficient tagging techniques are urgently needed to better understand the movement ecology of tropical river-floodplain species — both at a fundamental level and in response to the effects of barriers. Passive Integrated Transponder (PIT) tagging has been successfully used to quantify fish movements in many temperate riverine species, but its effectiveness on tropical riverine species remains largely untested. We investigated the potential use of PIT tags in two tropical species from the Mekong River — Pangasianodon hypophthalmus (Striped catfish) and Hypsibarbus malcolmi (Goldfin tinfoil barbs). Two separate, but concurrent, 50-day experiments were conducted on the two species to determine whether (1) the PIT tags can be retained within the fish, without affecting their mortality or growth, and (2) the outcomes for tag retention, fish mortality, and/or fish growth are influenced by the location of the tags in the fish. Results indicated that, for both species, PIT tags can be retained in the chest, gut or shoulder without affecting mortality or growth. This suggests that PIT tags could be successfully used in a range of body locations in Striped catfish and Goldfin tinfoil barbs in the Mekong River. However, the Mekong fishery is a highly important food source for the people of its neighbouring countries — thus, the most suitable tag location in large-bodied species would be the gut region, as the gut, and tag, are most likely to be removed prior to human consumption
The role of EGFR double minutes in modulating the response of malignant gliomas to radiotherapy.
EGFR amplification in cells having double minute chromosomes (DM) is commonly found in glioblastoma multiforme (GBM); however, how much it contributes to the current failure to treat GBM successfully is unknown. We studied two syngeneic primary cultures derived from a GBM with and without cells carrying DM, for their differential molecular and metabolic profiles, in vivo growth patterns, and responses to irradiation (IR). Each cell line has a distinct molecular profile consistent with an invasive "go" (with DM) or angiogenic "grow" phenotype (without DM) demonstrated in vitro and in intracranial xenograft models. Cells with DM were relatively radio-resistant and used higher glycolytic respiration and lower oxidative phosphorylation in comparison to cells without them. The DM-containing cell was able to restore tumor heterogeneity by mis-segregation of the DM-chromosomes, giving rise to cell subpopulations without them. As a response to IR, DM-containing cells switched their respiration from glycolic metabolism to oxidative phosphorylation and shifted molecular profiles towards that of cells without DM. Irradiated cells with DM showed the capacity to alter their extracellular microenvironment to not only promote invasiveness of the surrounding cells, regardless of DM status, but also to create a pro-angiogenic tumor microenvironment. IR of cells without DM was found primarily to increase extracellular MMP2 activity. Overall, our data suggest that the DM-containing cells of GBM are responsible for tumor recurrence due to their high invasiveness and radio-resistance and the mis-segregation of their DM chromosomes, to give rise to fast-growing cells lacking DM chromosomes
Recommended from our members
A cautionary tale about the inhibitory effects of gated culverts on fish passage restoration efforts
Connectivity between river-floodplain habitats has been heavily constrained in many large tropical river systems by the construction of regulators, levees and other physical barriers. Fishways are being constructed to ameliorate the effects of these barriers; but it is important that all aspects of fishway design cater for local target species. We investigated the lateral movement patterns of Lower Mekong Basin fish in Laos, through a fishway that incorporated a series of cones, resting pools, and a culvert with a vertical lift gate. Fish needed to negotiate all of these structures to move from the Mekong to an adjacent wetland. We tested the hypothesis that gated culverts may hamper the effectiveness of fishways, by comparing the abundance and species richness of fish at three locations along the path of the fishway and culvert: (1) the fishway entrance; (2) the fishway exit; and (3) the culvert exit (i.e. immediately upstream of the culvert). There were no marked differences in the total abundance and species richness of fish between the fishway entrance and culvert exit while the river remained at levels where the culvert was only partially inundated. Nevertheless, the abundance and species richness of fish were markedly lower at the culvert exit than at the fishway entrance and exit once the headwater levels rose to where the culvert was completely inundated. These findings indicate that fish were able to ascend the fishway but not the culvert once it became completely submerged, and thus support the hypothesis that gated culverts can hamper the effectiveness of fishways in facilitating the lateral movement of fish in large tropical systems. Fish passage at such installations can be enhanced through optimised operating regimes. Ensuring that headwater levels remain below the culvert ceiling is likely to be the best way to maximise fishway effectiveness
Origin and evolution of the octoploid strawberry genome.
Cultivated strawberry emerged from the hybridization of two wild octoploid species, both descendants from the merger of four diploid progenitor species into a single nucleus more than 1 million years ago. Here we report a near-complete chromosome-scale assembly for cultivated octoploid strawberry (Fragaria × ananassa) and uncovered the origin and evolutionary processes that shaped this complex allopolyploid. We identified the extant relatives of each diploid progenitor species and provide support for the North American origin of octoploid strawberry. We examined the dynamics among the four subgenomes in octoploid strawberry and uncovered the presence of a single dominant subgenome with significantly greater gene content, gene expression abundance, and biased exchanges between homoeologous chromosomes, as compared with the other subgenomes. Pathway analysis showed that certain metabolomic and disease-resistance traits are largely controlled by the dominant subgenome. These findings and the reference genome should serve as a powerful platform for future evolutionary studies and enable molecular breeding in strawberry
Cand1 Promotes Assembly of New SCF Complexes through Dynamic Exchange of F Box Proteins
The modular SCF (Skp1, cullin, and F box) ubiquitin ligases feature a large family of F box protein substrate receptors that enable recognition of diverse targets. However, how the repertoire of SCF complexes is sustained remains unclear. Real-time measurements of formation and disassembly indicate that SCF^(Fbxw7) is extraordinarily stable, but, in the Nedd8-deconjugated state, the cullin-binding protein Cand1 augments its dissociation by one-million-fold. Binding and ubiquitylation assays show that Cand1 is a protein exchange factor that accelerates the rate at which Cul1-Rbx1 equilibrates with multiple F box protein-Skp1 modules. Depletion of Cand1 from cells impedes recruitment of new F box proteins to pre-existing Cul1 and profoundly alters the cellular landscape of SCF complexes. We suggest that catalyzed protein exchange may be a general feature of dynamic macromolecular machines and propose a hypothesis for how substrates, Nedd8, and Cand1 collaborate to regulate the cellular repertoire of SCF complexes
- …