410 research outputs found
Survey of Computer-Aided Engineering Software for Mechanical Design
In academia and industries, Computer-Aided Design (CAD) programs are used extensively as they help streamline the product development process and reduce cost by allowing parts to be modeled iteratively at a higher precision within a shorter time. Additionally, Finite Element Analysis (FEA) and Computer-Aided Engineering (CAE) programs are used to solve complex mathematical models that simulate real-world working environments that are otherwise time and labor intensive to solve manually. Despite the importance of these programs, there are 3 classes across the undergraduate and graduate levels at Washington University in St. Louis that emphasizes learning such programs. For undergraduates, only MEMS 202 is required while MEMS 103 and MEMS 5104 are an elective undergraduate and graduate class respectively. Therefore, this independent study aims to produce a roadmap by which a graduate CAE class can follow to give the students a deeper understanding of various programs. This provides the students the knowledge to then be able to choose the appropriate program to use in their future work
Service Sabotage in Hotel Industry: Empirical Study Using Social Bonding Theory
Perlakuan sabotaj khidmat di tempat kerja, terutama sekali dalam industri perhotelan semakin berleluasan sehingga menarik perhatian pihak penyelidik dan pengurus.
Research and managerial interest in employees’ service sabotage behavior has become increasingly widespread, especially in the hotel industry
Grimoires: Grid Registry with Metadata Oriented Interface: Robustness, Efficiency, Security --- Work-in-Progress
Grid registries allow users to discover resources made available by Grid resource providers. In this paper, we present our on-going work on a next-generation registry, initially designed as part of the myGrid project and to be part of the OMII Grid software release. Specifically, we discuss the support of semantic service descriptions and task/user-specific metadata, along with related performance and security considerations
Rapid microwave-assisted CNBr cleavage of bead-bound peptides
Large libraries of peptides, cyclic peptides, and other molecules are standard tools for the discovery of drugs, molecular probes, and affinity reagents. In particular, one-bead-one-compound (OBOC) libraries,(1) prepared by the split-and-mix method,(2) provide access to a broad chemical space with a minimum of reagents. Once such a library has been screened against the target of interest, the chemical identity of the library elements on the hit beads is identified. For peptide libraries and their variants, mass spectrometry (MS) based peptide sequencing provides the most rapid method for such analysis. OBOC libraries are constructed in a number of ways to facilitate MS analysis,(3-5) but one common feature is that the peptide must be cleaved from the bead prior to being introduced into the mass spectrometer. While a number of chemical(6) and photochemical(7) cleavage strategies have been developed, the most common strategy is to incorporate a CNBr-cleavable methionine-linker group at the C-terminus of the peptide.(8) CNBr cleavage has also been widely used in proteomics to cleave proteins.(9) With such chemistry, up to 100 beads from an OBOC peptide library can be sequenced in a 24 h period.(10) A large fraction of that time, however, is devoted to the CNBr cleavage step. Standard literature protocols describe CNBr cleavage as requiring between 12 and 24 h, using 20−30 μL of 0.25 M CNBr in 70% aqueous formic acid at room temperature.(11) Although the CNBr cleavage time may be reduced to 2−4 h at elevated temperatures (47 °C), significant side-products may be generated.(12) All reports that we have found that describe CNBr cleavage chemistry from single beads have used the same conditions as for proteomics, although the two chemical processes are not necessarily equivalent
Automated small-scale plant imaging system
For research laboratories, the use of commercial plant phenotyping systems is costly and often do not meet the requirements of the research project. As such, a small-scale plant imaging systems was developed for a biology research group at Washington University in St. Louis. A previous iteration of the device had been prototyped; however, several design requirements were not met, or were not mechanically efficient. Therefore, this paper proposes a second design consisting of a new bridge, trolley and canopy that can be transported easily by the user, and can be made with commercially available parts
Autonomous Ground Photographer
Dr. Penczykowski, a biology professor at Washington University in St. Louis, researches the effects of powdery mildew on three plant species. Her lab currently collects data in the field by manually counting the number of infected plants with the assistance of a simple PVC grid. Therefore, this projects aims to automate this process by capturing images that can then be processed in her lab after
Ototoxicity from Combined Cisplatin and Radiation Treatment: An In Vitro Study
Objective. Combined cisplatin (CDDP) and radiotherapy is increasingly being used to treat advanced head and neck cancers. As both CDDP and radiation can cause hearing loss, it is important to have a better understanding of the cellular and molecular ototoxic mechanisms involved in combined therapy. Procedure.
The effects of CDDP, radiation, and combined CDDP-radiation on the OC-k3 cochlear cell line were studied using MTS assay, flow cytometry, Western blotting, and microarray analysis. Results. Compared to using CDDP or radiation alone, its combined use resulted in enhanced apoptotic cell death and apoptotic-related gene expression, including that of FAS. Phosphorylation of p53 at Ser15 (a marker for p53 pathway activation in response to DNA damage) was observed after treatment with either CDDP or radiation. However, posttreatment activation of p53 occurred earlier in radiation than in CDDP which corresponded to the timings of MDM2 and TP53INP1 expression. Conclusion. Enhanced apoptotic-related gene expressions leading to increased apoptotic cell deaths could explain the synergistic ototoxicity seen clinically in combined CDDP-radiation therapy. CDDP and radiation led to differential temporal activation of p53 which suggests that their activation is the result of different upstream processes. These have implications in future antiapoptotic treatments for ototoxicity
Analisis in silico peptida berasaskan epitop daripada protein-protein imunogen Burkholderia pseudomallei
Melioidosis is an infectious disease caused by the gram-negative bacterium Burkholderia pseudomallei. This disease is associated with high human mortality rate, especially in tropical and subtropical regions. Rapid diagnosis is crucial in ensuring proper management and treatment of the disease with effective antibiotics. Currently, melioidosis diagnosis, bacterial culture is time consuming, difficult, and not sensitive, while IHA is hindered by high antibody background in healthy population and ELISA lacks standardization and is hindered by antigen inconsistency. To improve the current diagnosis method for melioidosis, this research aims to identify, screen, and develop epitope-spanning peptides to be used as standardized B. pseudomallei antigen in serodiagnosis of melioidosis. Peptides are favoured as they are more stable, and they offer effective and rapid antibody detection. Using in silico analysis, a pool of 154 B. pseudomallei proteins previously reported as immunogenic were screened and ranked based on their antigenicity, subcellular localization, stability, adhesive properties, and ability to interact with class I and class II major histocompatibility complex (MHC). The selected candidate from the analysis, BPSS0908 and BPSL2152 were then taken for further analysis to identify linear B-cell epitopes using several sequence-based B-cell epitope prediction tools. Consensus sequences that are confidently predicted by more than two prediction tools and are longer than 15 amino acids were then selected as linear B-cell epitopes. Through ELISA analysis, low sensitivity was demonstrated by the epitope-spanning peptides as compared to B. pseudomallei crude lysate. However, high specificity of 100% was observed for all tested peptides. The low sensitivity demonstrated by the peptides in ELISA could be due to lack of 3-dimensional structure which is needed for a stable antigen-antibody binding
Accurate MALDI-TOF/TOF Sequencing of One-Bead−One-Compound Peptide Libraries with Application to the Identification of Multiligand Protein Affinity Agents Using in Situ Click Chemistry Screening
Combinatorial one-bead−one-compound (OBOC) peptide libraries are widely used for affinity screening, and the sequencing of peptides from hit beads is a key step in the process. For rapid sequencing, CNBr cleavage of the peptides from the beads, followed by de novo sequencing by MALDI-TOF/TOF, is explored. We report on a semiautomated sequencing algorithm and validate it through comparison against Edman degradation sequencing. The initial 44% sequencing success rate of the standard de novo sequencing software was improved to nearly 100%. The sequencing algorithm incorporates existing knowledge of amino acid chemistry and a new strategy for differentiating isobaric amino acids. We tested the algorithm by using MALDI-TOF/TOF to identify a peptide biligand affinity agent against the protein bovine carbonic anhydrase II, starting from comprehensive one-bead−one-compound peptide libraries comprised of non-natural and artificial amino acid components and using the strategy of in situ click/OBOC library screening
Relationships Between Self-Reported Smoking, Household Environmental Tobacco Smoke Exposure and Depressive Symptoms in a Pregnant Minority Population
This study sought to examine relationships between depressive symptoms and prenatal smoking and/or household environmental tobacco smoke exposure (HHETSE) among urban minority women. We analyzed private, audio computer-assisted self interview data from a clinic-based sample of 929 minority pregnant women in Washington, DC. Depressive symptoms were assessed via the Beck Depression Inventory Fast Screen. HH-ETSE, current smoking, and former smoking were assessed via self-report. Depression levels and demographic characteristics were compared: (1) among nonsmokers, for those reporting HH-ETSE versus no HH-ETSE; and (2) among smokers, for those reporting current smoking (in last 7 days) versus former smokers. Measures associated with HH-ETSE/current smoking in bivariate analysis at P\0.20 were included in adjusted logistic regression models. HH-ETSE, as a possible indicator of a social smoking network, was assessed as a mediator for the relationship between depression and current smoking. Results: Non-smokers reporting moderate-to-severe depressive symptoms showed significantly higher adjusted odds of prenatal HH-ETSE (AOR 2.5, 95% CI [1.2, 5.2]). Smokers reporting moderate-to-severe or mild depressive symptoms showed significantly higher adjusted odds of current smoking (AOR 1.9, 95% CI [1.1, 3.5] and AOR 1.8, 95% CI [1.1, 3.1], respectively). Among smokers, HH-ETSE was a significant mediator for the association between moderate-to-severe symptoms and current smoking. In conclusion, health care providers should be aware that depressed urban minority women are at risk of continued smoking/HH-ETSE during pregnancy. Interventions designed to encourage behavior change should include screening for depression, and build skills so that women are better able to address the social environment
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