2,380 research outputs found

    Is Discrimination Due to a Coordination Failure?

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    Can groups with equal productive potential end up in equilibria in which they get different average wages? We consider a simple model of statistical discrimination that shows that this might happen. Discrimination in this model is possible for the existence of multiple equilibria. We study what determines multiplicity, what policies might be used to eliminate discrimination in this situation and, finally, we test the main hypothesis of this model, namely, that identical groups will be treated equally. Our empirical results suggest, however, that discrimination is more due to structural differences in the wage schedules faced by black and white males.

    Antimicrobial resistance in patients with odontogenic infections : a systematic scoping review of prospective and experimental studies

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    Patients with odontogenic infections are commonly prescribed antimicrobials on an experiential base without knowing the precise microorganisms implicated. The aim of this systematic scoping review is to evaluate the prevalence and proportions of antimicr

    Evaluation of straight and swept ramp obstacles on enhancing deflagration-to-detonation transition in pulse detonation engines

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    The use of detonations to achieve thrust in pulse detonation engines (PDEs) offers significant advantages in efficiency, simplicity, and versatility. An enabling mechanism for practical PDE implementation will likely utilize an efficient deflagration-todetonation transition (DDT) process. This method simplifies detonation generation, but the required length is prohibitive in many applications and limits the frequency of repeatability. Obstacles have historically been employed to minimize the DDT distance, but often result in significant total pressure losses that degrade the delivered efficiency advantages of PDEs. This thesis explored the use of straight and swept ramp obstacles to accelerate DDT while minimizing the overall pressure losses. Computer modeling examined three-dimensional disturbances caused by such obstacles. Experimental tests measured combustion shockwave speed, flame velocity, and flame front interactions with obstacles. Evaluations were completed for several straight ramp obstacle configurations in a modeled two-dimensional flow. The placement of consecutive ramps resulted in flame acceleration accompanied by significant pressure spikes approaching 500 psi. Although detonation was not verified across the instrumented section, experimental data prove that straight ramp obstacles successfully accelerate the DDT process. Computer modeling predicts that swept ramps may be even more effective by introducing streamwise vorticity with a relatively low pressure drop.http://archive.org/details/evaluationofstra109452479Approved for public release; distribution is unlimited

    High resistance against clindamycin, metronidazole and amoxicillin in Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans isolates of periodontal disease

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    Objectives: To test the antimicrobial sensitivity of two periodontal pathogens to a panel of five orally administrable antibiotics in periodontal disease. Study design: A total of 69 isolates of Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis were processed using culture and biochemical tests. Selected colonies of A. actinomycetemcomitans and P. gingivalis were used to evaluate the antibacterial activity of clindamycin, metronidazole, amoxicillin, moxifloxacin and amoxicillin/clavulanic acid. Results: Susceptibility testing revealed a sensitivity of 100% of A. actinomycetemcomitans and P. gingivalis to moxifloxacin and amoxicillin/clavulanic acid but moderate susceptibilities were found for the rest of antibiotics agents evaluated. Conclusions: The widespread use of antibiotics is reflected in the level of resistance of A. actinomycetemcomitans and P. gingivalis in patients with periodontal infections. This suggests that antibiotic susceptibility testing is necessary to determine efficacy of antimicrobial agents. Clinical studies with antibiotics should take these differences into account

    Identification of novel amplification gene targets in mouse and human breast cancer at a syntenic cluster mapping to mouse identification of novel amplification gene targets in mouse and human breast cancer at a syntenic cluster mapping to mouse ch8a1 and human ch13q34

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    Serial analysis of gene expression from aggressive mammary tumors derived from transplantable p53 null mouse mammary outgrowth lines revealed significant up-regulation of Tfdp1 (transcription factor Dp1), Lamp1 (lysosomal membrane glycoprotein 1) and Gas6 (growth arrest specific 6) transcripts. All of these genes belong to the same linkage cluster, mapping to mouse chromosome band 8A1. BAC-array comparative genomic hybridization and fluorescence in situ hybridization analyses revealed genomic amplification at mouse region ch8A1.1. The minimal region of amplification contained genes Cul4a, Lamp1, Tfdp1, and Gas6, highly overexpressed in the p53 null mammary outgrowth lines at preneoplastic stages, and in all its derived tumors. The same amplification was also observed in spontaneous p53 null mammary tumors. Interestingly, this region is homologous to human chromosome 13q34, and some of the same genes were previously observed amplified in human carcinomas. Thus, we further investigated the occurrence and frequency of gene amplification affecting genes mapping to ch13q34 in human breast cancer. TFDP1 showed the highest frequency of amplification affecting 31% of 74 breast carcinomas analyzed. Statistically significant positive correlation was observed for the amplification of CUL4A, LAMP1, TFDP1, and GAS6 genes (P < 0.001). Meta-analysis of publicly available gene expression data sets showed a strong association between the high expression of TFDP1 and decreased overall survival (P = 0.00004), relapse-free survival (P = 0.0119), and metastasis-free interval (P = 0.0064). In conclusion, our findings suggest that CUL4A, LAMP1, TFDP1, and GAS6 are targets for overexpression and amplification in breast cancers. Therefore, overexpression of these genes and, in particular, TFDP1 might be of relevance in the development and/or progression in a significant subset of human breastFil: Abba, Martín Carlos. University of Texas; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fabris, Victoria Teresa. University of Texas; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Hu, Yuhui. University of Texas; Estados UnidosFil: Kittrell, Frances S.. Baylor College of Medicine; Estados Unidos. University of Texas; Estados UnidosFil: Cai, Wei Wen. University of Texas; Estados Unidos. Baylor College of Medicine; Estados UnidosFil: Donehower, Lawrence A.. University of Texas; Estados UnidosFil: Sahin, Aysegui. University of Texas; Estados UnidosFil: Medina, Daniel. University of Texas; Estados Unidos. Baylor College of Medicine; Estados UnidosFil: Aldaz, Claudio Marcelo. University of Texas; Estados Unido

    One year follow-up of a randomized trial with a dilemma-focused intervention for depression: Exploring an alternative to problem-oriented strategies

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    © 2018 Feixas et al.Cognitive behavioural therapy (CBT) is aimed to counteract cognitions and behaviours that are considered as dysfunctional. The aim of the study is to test whether the inclusion of a non-counteractive approach (dilemma-focused intervention, DFI) in combination with CBT group therapy will yield better short- and long-term outcomes than an intervention conducted entirely using CBT.Peer reviewedFinal Published versio
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