Washington State University

About: Washington State University is a education organization based out in Pullman, Washington, United States. It is known for research contribution in the topics: Population & Gene. The organization has 26947 authors who have published 57736 publications receiving 2341509 citations. The organization is also known as: WSU & Wazzu.

Transfer learning for activity recognition: a survey

Abstract: Many intelligent systems that focus on the needs of a human require information about the activities being performed by the human. At the core of this capability is activity recognition, which is a challenging and well-researched problem. Activity recognition algorithms require substantial amounts of labeled training data yet need to perform well under very diverse circumstances. As a result, researchers have been designing methods to identify and utilize subtle connections between activity recognition datasets, or to perform transfer-based activity recognition. In this paper, we survey the literature to highlight recent advances in transfer learning for activity recognition. We characterize existing approaches to transfer-based activity recognition by sensor modality, by differences between source and target environments, by data availability, and by type of information that is transferred. Finally, we present some grand challenges for the community to consider as this field is further developed.

Temperature dependence of the thermal conductivity of single-wall carbon nanotubes

Abstract: The thermal conductivity of several single-wall carbon nanotubes has been calculated over a temperature range of 100-500 K using molecular dynamics simulations with the Tersoff-Brenner potential for C-C interactions. In all cases, starting from similar values at 100 K, the thermal conductivities show a peaking behaviour before falling off at higher temperatures. The peak position shifts to higher temperatures for nanotubes with larger diameters and no significant dependence on the tube chirality is observed. It is shown that this phenomenon is due to the onset of Umklapp scattering, which shifts to higher temperatures for nanotubes with larger diameters.

Kit-Ligand/Stem Cell Factor Induces Primordial Follicle Development and Initiates Folliculogenesis

Abstract: Initiation of folliculogenesis through the induction of primordial follicle development in the ovary has an important role in determining the fertility and reproductive fitness of most mammalian species. The factors that control this critical process are largely unknown. The hypothesis tested in the current study was that kit-ligand/stem cell factor (KL) promotes the initiation and progression of primordial follicle development in the ovary. Ovaries from 4-day-old rats were maintained in organ culture for 5 and 14 days and treated with no factor (control), recombinant kit-ligand (KL), or gonadotropins (FSH and hCG). Follicles in ovarian sections were counted and histologically classified as primordial (stage 0), early primary (stage 1), primary (stage 2), transitional (stage 3), or preantral (stage 4). Fresh ovaries from 4-day-old rats contained 68% primordial follicles (stage 0) and 32% developing follicles (stages 1-4) per section. After 5 and 14 days in culture, section from control ovaries contained approximately 41% and 55%, respectively, developing follicles (stage 1-4) per section due to spontaneous development of primordial follicles. Spontaneous primordial follicle development was completely blocked by ACK-2, a c-kit antibody that blocks KL actions. This observation suggests that endogenous KL is necessary for primordial follicle development in vitro. After 14 days of KL treatment, sections from ovaries contained 17% primordial follicles (stage 0) and 83% developing follicles (stage 1-4) per section demonstrating a dramatic induction of primordial follicle development by KL. Gonadotropins (FSH and hCG) did not induce primordial follicle development but did increase the percentage of preantral follicles (stage 4) per section. This small increase in preantral follicles in response to gonadotropins was blocked by ACK-2 suggesting that KL may in part mediate gonadotropin actions after the initiation of primordial follicle development. Ovaries contained an average of 309+/-10 follicles per section. The total number of follicles per section did not significantly vary between treatments suggesting that the effects of KL were not due to an alteration in follicle number (i.e. survival). KL appears to be one of the first factors identified to be involved in the promotion of primordial follicle development. Results suggest that KL is necessary and sufficient to induce primordial follicle development and initiate folliculogenesis.

The barley stem rust-resistance gene Rpg1 is a novel disease-resistance gene with homology to receptor kinases

Abstract: Stem rust caused by Puccinia graminis f. sp. tritici was among the most devastating diseases of barley in the northern Great Plains of the U.S. and Canada before the deployment of the stem rust-resistance gene Rpg1 in 1942. Since then, Rpg1 has provided durable protection against stem rust losses in widely grown barley cultivars (cvs.). Extensive efforts to clone Rpg1 by synteny with rice provided excellent flanking markers but failed to yield the gene because it does not seem to exist in rice. Here we report the map-based cloning and characterization of Rpg1. A high-resolution genetic map constructed with 8,518 gametes and a 330-kb bacterial artificial chromosome contig physical map positioned the gene between two crossovers approximately 0.21 centimorgan and 110 kb apart. The region including Rpg1 was searched for potential candidate genes by sequencing low-copy probes. Two receptor kinase-like genes were identified. The candidate gene alleles were sequenced from resistant and susceptible cvs. Only one of the candidate genes showed a pattern of apparently functional gene structure in the resistant cvs. and defective gene structure in the susceptible cvs. identifying it as the Rpg1 gene. Rpg1 encodes a receptor kinase-like protein with two tandem protein kinase domains, a novel structure for a plant disease-resistance gene. Thus, it may represent a new class of plant resistance genes.

Taxol Biosynthesis and Molecular Genetics

Abstract: Biosynthesis of the anticancer drug Taxol in Taxus (yew) species involves 19 steps from the universal diterpenoid progenitor geranylgeranyl diphosphate derived by the plastidial methyl erythritol phosphate pathway for isoprenoid precursor supply. Following the committed cyclization to the taxane skeleton, eight cytochrome P450-mediated oxygenations, three CoA-dependent acyl/aroyl transfers, an oxidation at C9, and oxetane (D-ring) formation yield the intermediate baccatin III, to which the functionally important C13-side chain is appended in five additional steps. To gain further insight about Taxol biosynthesis relevant to the improved production of this drug, and to draw inferences about the organization, regulation, and origins of this complex natural product pathway, Taxus suspension cells (induced for taxoid biosynthesis by methyl jasmonate) were used for feeding studies, as the foundation for cell-free enzymology and as the source of transcripts for cDNA library construction and a variety of cloning strategies. This approach has led to the elucidation of early and late pathway segments, the isolation and characterization of over half of the pathway enzymes and their corresponding genes, and the identification of candidate cDNAs for the remaining pathway steps, and it has provided many promising targets for genetically engineering more efficient biosynthetic production of Taxol and its precursors.