Application of a portable FTIR for measuring on-road emissions

The objective of this work was the development of an onroad in-vehicle emissions measurement technique utilizing a relatively new, commercial, portable Fourier Transform Infra-Red (FTIR) Spectrometer capable of identifying and measuring (at approximately 3 second intervals) up to 51 different compounds. The FTIR was installed in a medium class EURO1 spark ignition passenger vehicle in order to measure on-road emissions. The vehicle was also instrumented to allow the logging of engine speed, road speed, global position, throttle position, air-fuel ratio, air flow and fuel flow in addition to engine, exhaust and catalyst temperatures. This instrumentation allowed the calculation of massbased emissions from the volume-based concentrations measured by the FTIR. To validate the FTIR data, the instrument was used to measure emissions from an engine subjected to a real-world drive cycle using an AC dynamometer. Standard analyzers were operated simultaneously for comparison with the FTIR and the standard analyzer results showed that most pollutants (NOx, CO2, CO) were within ~10% of a standard analyzer during steady state conditions and within 20% during transients. The exception to this was total HC which was generally 50% or less than actual total HC, but this was due to the limited number of hydrocarbons measured by the FTIR. In addition to the regulated emissions, five toxic hydrocarbon species were analyzed and found to be sensitive to cold starts in varying proportions. Finally, FTIR data was compared to results from a commercially available on-road measurement system (Horiba OBS- 1000), and there was good agreement

Rediseño de la intranet de la empresa Controltek S.A.C. usando servidores redundantes open source sobre vlan´s para optimizar el flujo de información

La empresa de la cual será objeto de estudio tiene problemas frecuentes desde hace algunos años con su Intranet, lo cual genera problemas de conexión internas en la red de la empresa, perdida de información, caídas repentinas de los servidores y virus informáticos que llegan desde el exterior de la Intranet. La presente tesis se focaliza en el objetivo de proponer un rediseño de la Intranet con el cual se podrá mejorar el rendimiento de la red para optimizar el flujo de información y minimizar los agentes infecciosos para la empresa, con el único propósito de que todos los trabajadores puedan estar conectados a la red sin interrupciones y poder acrecentar la productividad. Esta propuesta de mejora se da utilizando los Simuladores Riverbed Modeler Academic Edition y Packet Tracer, en donde se puede diseñar la actual topología de red Star con muchos dominios de broadcast y rediseñar la nueva topología de red con VLAN´s limitando estos dominios. Estos diseños realizados nos llevan a poder confrontar las dos Topologías, apreciando las deficiencias en la red actual y las mejoras en el nuevo rediseño planteado. Se utiliza también los programas XAMPP y Workbench para elaborar la base de datos con el Modelo Relacional y por último Linux para llevar a cabo los servidores redundantes; Todo eso para alcanzar los objetivos propuestos. Este rediseño planteado permite organizar y gestionar mejor la red, garantizando el ancho de banda, prioridad de la transmisión y fragmentando el dominio de broadcast al utilizar switches; obteniendo un progreso significativo en el rendimiento de la red, permitiendo una fácil y fluida circulación de información para cada uno de los trabajadores que son parte de en las áreas o departamentos de la empresa y a los eslabones que constituyen la pirámide jerárquica de la administración. Eso sí, con apego a las mejores especificaciones técnicas y a la mejor visión futurista que en el momento sea posible. Palabras clave: red, switch, router, VLAN, broadcast, ancho de banda, latencia, base de datos.Tesi

Draft Genome Sequence of Pseudoalteromonas sp. Strain JC3

We report the draft genome sequence for Pseudoalteromonas sp. strain JC3, an isolate obtained from an aquaculture facility for whiteleg shrimp (Litopenaeus vannamei). The JC3 genome suggests multiple mechanisms for microbial interactions, including a type VI secretion system and potential for antibiotic production

Stability and Change in Self-Reported Sexual Orientation Identity in Young People: Application of Mobility Metrics

This study investigated stability and change in self-reported sexual orientation identity over time in youth. We describe gender- and age-related changes in sexual orientation identity from early adolescence through emerging adulthood in 13,840 youth ages 12–25 employing mobility measure M, a measure we modified from its original application for econometrics. Using prospective data from a large, ongoing cohort of U.S. adolescents, we examined mobility in sexual orientation identity in youth with up to four waves of data. Ten percent of males and 20% of females at some point described themselves as a sexual minority, while 2% of both males and females reported ever being “unsure” of their orientation. Two novel findings emerged regarding gender and mobility: (1) Although mobility scores were quite low for the full cohort, females reported significantly higher mobility than did males. (2) As expected, for sexual minorities, mobility scores were appreciably higher than for the full cohort; however, the gender difference appeared to be eliminated, indicating that changing reported sexual orientation identity throughout adolescence occurred at a similar rate in female and male sexual minorities. In addition, we found that, of those who described themselves as “unsure” of their orientation identity at any point, 66% identified as completely heterosexual at other reports and never went on to describe themselves as a sexual minority. Age was positively associated with endorsing a sexual-minority orientation identity. We discuss substantive and methodological implications of our findings for understanding development of sexual orientation identity in young people

Natural and synthetic tetracycline-inducible promoters for use in the antibiotic-producing bacteria Streptomyces

Bacteria in the genus Streptomyces are major producers of antibiotics and other pharmacologically active compounds. Genetic and physiological manipulations of these bacteria are important for new drug discovery and production development. An essential part of any ‘genetic toolkit’ is the availability of regulatable promoters. We have adapted the tetracycline (Tc) repressor/operator (TetR/tetO) regulatable system from transposon Tn10 for use in Streptomyces. The synthetic Tc controllable promoter (tcp), tcp830, was active in a wide range of Streptomyces species, and varying levels of induction were observed after the addition of 1–100 ng/ml of anhydrotetracycline (aTc). Streptomyces coelicolor contained an innate Tc-controllable promoter regulated by a TetR homologue (SCO0253). Both natural and synthetic promoters were active and inducible throughout growth. Using the luxAB genes expressing luciferase as a reporter system, we showed that induction factors of up to 270 could be obtained for tcp830. The effect of inducers on the growth of S.coelicolor was determined; addition of aTc at concentrations where induction is optimal, i.e. 0.1–1 μg/ml, ranged from no effect on growth rate to a small increase in the lag period compared with cultures with no inducer

Natural and synthetic tetracycline-inducible promoters for use in the antibiotic-producing bacteria Streptomyces

[EN] Bacteria in the genus Streptomyces are major producers of antibiotics and other pharmacologically active compounds. Genetic and physiological manipulations of these bacteria are important for new drug discovery and production development. An essential part of any ‘genetic toolkit’ is the availability of regulatable promoters. We have adapted the tetracycline (Tc) repressor/operator (TetR/ tetO ) regulatable system from transposon Tn 10 for use in Streptomyces . The synthetic Tc controllable promoter (tcp), tcp830 , was active in a wide range of Streptomyces species, and varying levels of induction were observed after the addition of 1–100 ng/ml of anhydrotetracycline (aTc). Streptomyces coelicolor contained an innate Tc-controllable promoter regulated by a TetR homologue (SCO0253). Both natural and synthetic promoters were active and inducible throughout growth. Using the luxAB genes expressing luciferase as a reporter system, we showed that induction factors of up to 270 could be obtained for tcp830 . The effect of inducers on the growth of S.coelicolor was determined; addition of aTc at concentrations where induction is optimal, i.e. 0.1–1 μg/ml, ranged from no effect on growth rate to a small increase in the lag period compared with cultures with no inducerSIThe authors acknowledge gifts of plasmids and strains from Prof. Leadlay, Prof. Hillen, Prof. Bujard, Dr Herron and Dr Paget. The authors thank Dr Sumby, Dr Ding and Wael Hussein for the construction of several plasmids and vectors. The authors also thank Prof. Williams for the use of Lucy. This work was funded by the BBSRC. Funding to pay the Open Access publication charges for this article was provided by JIS

Repeated Changes in Reported Sexual Orientation Identity Linked to Substance Use Behaviors in Youth

Purpose—Previous studies have found that sexual minority (e.g., lesbian, gay, bisexual) adolescents are at higher risk of substance use than heterosexuals, but few have examined how changes in sexual orientation over time may relate to substance use. We examined the associations between change in sexual orientation identity and marijuana use, tobacco use, and binge drinking in U.S. youth. Methods—Prospective data from 10,515 U.S. youth ages 12-27 years in a longitudinal cohort study were analyzed using sexual orientation identity mobility measure M (frequency of change from 0 [no change] to 1 [change at every wave]) in up to five waves of data. Generalized estimating equations were used to estimate substance use risk ratios and 95% confidence intervals; interactions by sex and age group were assessed. Results—All substance use behaviors varied significantly by sexual orientation. Sexual minorities were at higher risk for all outcomes, excluding binge drinking in males, and mobility score was positively associated with substance use in most cases (p\u3c.05). The association between mobility and substance use remained significant after adjusting for current sexual orientation and varied by sex and age for selected substance use behaviors. This association had a higher positive magnitude in females than males and in adolescents than young adults. Conclusions—In both clinical and research settings it is important to assess history of sexual orientation changes. Changes in reported sexual orientation over time may be as important as current sexual orientation for understanding adolescent substance use risk

Research-Practice Partnerships as Community-Engaged Learning: Lessons Learned from a Collaborative Project with Youth Development Programs

To bridge the gap between community-engaged learning and research-practice partnerships, we describe our experiences in a project jointly conceptualized and implemented by undergraduate students and youth development practitioners over the course of two academic semesters. The project offered students the opportunity to apply the skills they learned through coursework in a way that also supported the needs of community practitioners, providing both groups with opportunities to learn from each other. In this paper we describe the collaborative project, our process, the challenges we faced, and the impact of the project on the student researchers and the youth development practitioners. Written by representatives of both the student researchers and the practitioner collaborators, we hope this paper will inspire others to incorporate students in research-practice partnerships and that our reflections on the strengths and challenges of this process will facilitate more effective implementation of community-engaged scholarship in the future