889 research outputs found

    Boundary Objects in Design: An Ecological View of Design Artifacts

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    Traditionally, Systems Analysis and Design (SAD) research has focused on ways of working and ways of modeling. Design ecology – the task, organizational and political context surrounding design – is less well understood. In particular, relationships between design routines and products within ecologies have not received sufficient attention. In this paper, we theorize about design product and ecology relationships and deliberate on how design products – viewed as boundary objects – bridge functional knowledge and stakeholder power gaps across different social worlds. We identify four essential features of design boundary objects: capability to promote shared representation, capability to transform design knowledge, capability to mobilize for action, and capability to legitimize design knowledge. We show how these features help align, integrate, and transform heterogeneous technical and domain knowledge across social worlds as well as mobilize, coordinate, and align stakeholder power. We illustrate through an ethnography of a large aerospace laboratory how two design artifacts – early proto-architectures and project plans – shared these four features to coalesce design processes and propel successful movement of designs across social worlds. These artifacts resolved uncertainty associated with functional requirements and garnered political momentum to choose among design solutions. Altogether, the study highlights the importance of design boundary objects in multi-stakeholder designs and stresses the need to formulate sociology-based design theories on how knowledge is produced and consumed in complex SAD tasks

    Bi-Objective Rich Vehicle Routing Problem with Customer Prioritization

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    This paper considers a rich vehicle routing problem in which a combination of transportation costs and customer perceived waiting times should be minimized and a differentiation is made between priority and non-priority customers. We illustrate the problem using a case study of a wholesaler with its own last-mile delivery network where customers can have pickup and delivery demand and are served by a heterogeneous fleet of vehicles. We propose a bi-objective mathematical problem formulation, minimizing the combination of transportation costs and customer dissatisfaction. We model customer dissatisfaction using a non-linear function that approximates the perceived waiting time of the customers. To be able to solve realistically sized problems in reasonable time, we propose a Simulated Annealing heuristic, Variable Neighborhood Search, and a combination of these. We perform various experiments considering different customer preferences (visit as soon as possible or at a specific time) and problem settings. For the combined objective, we see an average costs reduction for the dissatisfaction function approach compared to the standard time window approach of 48% over all experiments. Furthermore, we observe an average reduction in perceived waiting time of 48% and 20% for priority and non-priority customers, respectively

    Interactive Effects of 1, 25-dihydroxyvitamin D3 and Soy Protein Extract (SPE) on Oral Cancer Growth In Vitro: Evidence for Potential Functional Relationships

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    ABSTRACTBackground: Previous studies have found specific soy isoflavones (Genistein, Daidzein, Glycitein) demonstrate anti-tumor properties against several cancer types, including oral cancer. Few studies have evaluated whole soy extract, containing a combination of these isoflavones and other bioreactive compounds, which may function synergistically and more effectively against oral cancers. Preliminary work by this group has now demonstrated whole soy protein extract (SPE) inhibits oral cancer cell growth specifically and selectively, through independent cell-cycle and apoptotic pathways. However, more recent evidence now suggests that ingestion of vitamin D3, either in dietary foods or supplements may potentiate the activity of soy components and their anti-tumor effects.Objective: The primary goal of this study was to investigate the interactive and inter-connected effects of 1, 25-dihydroxyvitamin D3 administration with the anti-proliferative effects of whole soy protein extract (SPE) on oral cancer and normal cell lines in vitro.Methods: Three oral squamous cell carcinoma cell lines (SCC15, SCC25, and CAL27) were treated with 1, 25-dihydroxy Vitamin D3 at physiological concentrations (10-125 nmol). Cell growth was then compared with cell treatment using soy protein extract (SPE) within the normal physiologic range (0 - 10 /L). Interactive effects were then evaluated using co-administration of SPE and 1, 25-dihydroxy Vitamin D3. Quantitative RT-PCR was performed at various time points to determine any changes in mRNA expression for key cell cycle and apoptotic signaling pathway regulators, including p53, c-myc, ornithine decarboxylase (ODC), caspase-2, caspase-8, and bax.Results: Administration of 1, 25-dihydroxy Vitamin D3 induced distinct dose-dependent, growth-inhibitory effects in all three oral cancer cell lines examined. These inhibitory effects were comparable to the overall range of growth inhibition induced by SPE. However, the combined effects of co-administration were far greater, suggesting the presence of synergistic relationships between these components. In addition, these results indicate that either treatment alone appeared to modulate mRNA expression of oral cancer cell-cycle promoters c-myc and ODC, as well as the caspase-dependent apoptosis pathway, while only 1, 25-dihydroxy Vitamin D3 administration appeared to influence the bax pathway.Conclusion: These results suggest that co-administration with 1, 25-dihydroxy Vitamin D3 and SPE may enhance their anti-tumor effects. This study may help to explain, in part, why balanced diets rich in fruits, vegetables, and soy protein, are associated with protection against development and progression of oral cancers, although further study is needed to develop specific public health recommendations for oral cancer treatment and prevention.Key words: vitamin D, soy extract, whole soy protein, oral cancer, growth inhibition

    Bacillus anthracis genome organization in light of whole transcriptome sequencing

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    Emerging knowledge of whole prokaryotic transcriptomes could validate a number of theoretical concepts introduced in the early days of genomics. What are the rules connecting gene expression levels with sequence determinants such as quantitative scores of promoters and terminators? Are translation efficiency measures, e.g. codon adaptation index and RBS score related to gene expression? We used the whole transcriptome shotgun sequencing of a bacterial pathogen Bacillus anthracis to assess correlation of gene expression level with promoter, terminator and RBS scores, codon adaptation index, as well as with a new measure of gene translational efficiency, average translation speed. We compared computational predictions of operon topologies with the transcript borders inferred from RNA-Seq reads. Transcriptome mapping may also improve existing gene annotation. Upon assessment of accuracy of current annotation of protein-coding genes in the B. anthracis genome we have shown that the transcriptome data indicate existence of more than a hundred genes missing in the annotation though predicted by an ab initio gene finder. Interestingly, we observed that many pseudogenes possess not only a sequence with detectable coding potential but also promoters that maintain transcriptional activity

    Daubechies wavelets as a basis set for density functional pseudopotential calculations

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    Daubechies wavelets are a powerful systematic basis set for electronic structure calculations because they are orthogonal and localized both in real and Fourier space. We describe in detail how this basis set can be used to obtain a highly efficient and accurate method for density functional electronic structure calculations. An implementation of this method is available in the ABINIT free software package. This code shows high systematic convergence properties, very good performances and an excellent efficiency for parallel calculations.Comment: 15 pages, 11 figure

    Insulin clearance and the incidence of type 2 diabetes in Hispanics and African Americans: the IRAS Family Study.

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    ObjectiveWe aimed to identify factors that are independently associated with the metabolic clearance rate of insulin (MCRI) and to examine the association of MCRI with incident type 2 diabetes in nondiabetic Hispanics and African Americans.Research design and methodsWe investigated 1,116 participants in the Insulin Resistance Atherosclerosis Study (IRAS) Family Study with baseline examinations from 2000 to 2002 and follow-up examinations from 2005 to 2006. Insulin sensitivity (S(I)), acute insulin response (AIR), and MCRI were determined at baseline from frequently sampled intravenous glucose tolerance tests. MCRI was calculated as the ratio of the insulin dose over the incremental area under the curve of insulin. Incident diabetes was defined as fasting glucose β‰₯126 mg/dL or antidiabetic medication use by self-report.ResultsWe observed that S(I) and HDL cholesterol were independent positive correlates of MCRI, whereas fasting insulin, fasting glucose, subcutaneous adipose tissue, visceral adipose tissue, and AIR were independent negative correlates (all P < 0.05) at baseline. After 5 years of follow-up, 71 (6.4%) participants developed type 2 diabetes. Lower MCRI was associated with a higher risk of incident diabetes after adjusting for demographics, lifestyle factors, HDL cholesterol, indexes of obesity and adiposity, and insulin secretion (odds ratio 2.01 [95% CI 1.30-3.10], P = 0.0064, per one-SD decrease in loge-transformed MCRI).ConclusionsOur data showed that lower MCRI predicts the incidence of type 2 diabetes

    Helping Psych Students Understand Their Employable Skill Set

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    Introduction Psychology students are underemployed after graduation despite being a part of one of the largest majors nationwide (Burning Glass Technologies, 2018; The Ladders, 2019; National Center for Education Statistics, 2019). In order to remedy this, our study will investigate how many and which careers psychology students are minimally qualified for. We hypothesize the knowledge skills and abilities (KSAOs) psychology students obtain during their undergraduate career will ensure they are minimally qualified for a wide range of careers across industries after graduation. Methods and Analyses In the previous stage of our research project (Todd et al., 2021), we compiled and validated a list of 42 KSAOs psychology students gained from their undergraduate curriculum by interviewing subject matter experts (i.e., faculty) via Qualtrics on the level of each KSAO obtained by a C student in a psychology class using a 1-7 Likert scale. In this stage, we will use those KSAO level scores in conjunction with O*Net data on the KSAOs necessary to perform a job to identify roles psychology students are minimally qualified for meaning they meet most, 80%, of the job requirements. Our analyses will involve compiling the KSAOs a student has from the courses they’ve taken and ranking their level of each KSAO on the highest level obtained (e.g. two courses with the same KSAO but different levels of expertise). That list of KSAOs will then be compared against O*Nets database of KSAO requirements for careers. Individuals will be returned a list of careers in which 80% of the required KSAOs for those careers match with those they obtained through their coursework. Expected Results and Implications We expect to confirm our hypothesis that the KSAOs psychology students obtain during their undergraduate career will make them minimally eligible for a range of careers across industries. The implications of this finding reside in its use with the website we plan to launch, Eugene. This program will allow psychology students to insert a list of classes and return the KSAOs they have and to which level and the careers correlated with those KSAOs. This will help students grasp a broader understanding of their competencies as well as careers they are eligible for

    Feasibility of non-lethal approaches to protect riparian plants from foraging beavers in North America

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    Beavers in North America will occupy almost any wetland area containing available forage. Wetland restoration projects often provide the resources necessary for dispersing beavers to create desirable habitats. Their wide distribution and ability to disperse considerable distances almost assure that beavers will establish themselves in new wetlands. Although beavers are a natural and desirable component of a wetland ecosystem, their foraging behaviors can be destructive. Fencing may be a feasible approach to reduce damage to small, targeted areas, and textural repellents may provide some utility to protect established trees. However, these non-lethal approaches will be marginally effective when beaver populations become excessive. Beaver populations need to be maintained at levels that permit viable colonies while still permitting plant communities to flourish. This will require a better understanding of beaver movements, site and forage selection, and reproductive characteristics. This is particularly true when management objectives and regulations prohibit beaver removal from project sites

    REST and CoREST Modulate Neuronal Subtype Specification, Maturation and Maintenance

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    BACKGROUND: The repressor element-1 silencing transcription factor/neuron-restrictive silencer factor (REST/NRSF) is a master regulator of neuronal gene expression. REST functions as a modular scaffold for dynamic recruitment of epigenetic regulatory factors including its primary cofactor, the corepressor for element-1-silencing transcription factor (CoREST), to genomic loci that contain the repressor element-1 (RE1) binding motif. While REST was initially believed to silence RE1 containing neuronal genes in neural stem cells (NSCs) and non-neuronal cells, emerging evidence shows an increasingly complex cell type- and developmental stage-specific repertoire of REST target genes and functions that include regulation of neuronal lineage maturation and plasticity. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we utilized chromatin immunoprecipitation on chip (ChIP-chip) analysis to examine REST and CoREST functions during NSC-mediated specification of cholinergic neurons (CHOLNs), GABAergic neurons (GABANs), glutamatergic neurons (GLUTNs), and medium spiny projection neurons (MSNs). We identified largely distinct but overlapping profiles of REST and CoREST target genes during neuronal subtype specification including a disproportionately high percentage that are exclusive to each neuronal subtype. CONCLUSIONS/SIGNIFICANCE: Our findings demonstrate that the differential deployment of REST and CoREST is an important regulatory mechanism that mediates neuronal subtype specification by modulating specific gene networks responsible for inducing and maintaining neuronal subtype identity. Our observations also implicate a broad array of factors in the generation of neuronal diversity including but not limited to those that mediate homeostasis, cell cycle dynamics, cell viability, stress responses and epigenetic regulation
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