Kinetics of n-Butoxy and 2-Pentoxy Isomerization and Detection of Primary Products by Infrared Cavity Ringdown Spectroscopy

The primary products of n-butoxy and 2-pentoxy isomerization in the presence and absence of O_2 have been detected using pulsed laser photolysis-cavity ringdown spectroscopy (PLP-CRDS). Alkoxy radicals n-butoxy and 2-pentoxy were generated by photolysis of alkyl nitrite precursors (n-butyl nitrite or 2-pentyl nitrite, respectively), and the isomerization products with and without O_2 were detected by infrared cavity ringdown spectroscopy 20 μs after the photolysis. We report the mid-IR OH stretch (ν_1) absorption spectra for δ-HO-1-C_4H_8•, δ-HO-1-C_4H_8OO•, δ-HO-1-C_5H_(10)•, and δ-HO-1-C_5H_(10)OO•. The observed ν_1 bands are similar in position and shape to the related alcohols (n-butanol and 2-pentanol), although the HOROO• absorption is slightly stronger than the HOR• absorption. We determined the rate of isomerization relative to reaction with O_2 for the n-butoxy and 2-pentoxy radicals by measuring the relative ν_1 absorbance of HOROO• as a function of [O_2]. At 295 K and 670 Torr of N_2 or N_2/O_2, we found rate constant ratios of k_(isom)/k_(O2) = 1.7 (±0.1) × 10^(19) cm^(–3) for n-butoxy and k_(isom)/k_(O2) = 3.4(±0.4) × 10^(19) cm^(–3) for 2-pentoxy (2σ uncertainty). Using currently known rate constants k_(O2), we estimate isomerization rates of k_(isom) = 2.4 (±1.2) × 10^5 s^(–1) and k_(isom) ≈ 3 × 10^5 s^(–1) for n-butoxy and 2-pentoxy radicals, respectively, where the uncertainties are primarily due to uncertainties in k_(O2). Because isomerization is predicted to be in the high pressure limit at 670 Torr, these relative rates are expected to be the same at atmospheric pressure. Our results include corrections for prompt isomerization of hot nascent alkoxy radicals as well as reaction with background NO and unimolecular alkoxy decomposition. We estimate prompt isomerization yields under our conditions of 4 ± 2% and 5 ± 2% for n-butoxy and 2-pentoxy formed from photolysis of the alkyl nitrites at 351 nm. Our measured relative rate values are in good agreement with and more precise than previous end-product analysis studies conducted on the n-butoxy and 2-pentoxy systems. We show that reactions typically neglected in the analysis of alkoxy relative kinetics (decomposition, recombination with NO, and prompt isomerization) may need to be included to obtain accurate values of k_(isom)/k_(O2)

The immunogenicity of recombinant vaccines based on modified Vaccinia Ankara (MVA) viruses expressing African horse sickness virus VP2 antigens depends on the levels of expressed VP2 protein delivered to the host

African horse sickness (AHS) is a lethal equine disease transmitted by Culicoides biting midges and caused by African horse sickness virus (AHSV). AHS is endemic to sub-Saharan Africa, but devastating outbreaks have been recorded periodically outside this region. The perceived risk of an AHS outbreak occurring in Europe has increased following the frequent epidemics caused in ruminants by bluetongue virus, closely related to AHSV. Attenuated vaccines for AHS are considered unsuitable for use in non-endemic countries due bio-safety concerns. Further, attenuated and inactivated vaccines are not compatible with DIVA (differentiate infected from vaccinated animals) strategies. All these factors stimulated the development of novel AHS vaccines that are safer, more efficacious and DIVA compatible. We showed previously that recombinant modified Vaccinia Ankara virus (MVA) vaccines encoding the outer capsid protein of AHSV (AHSV-VP2) induced virus neutralising antibodies (VNAb) and protection against AHSV in a mouse model and also in the horse. Passive immunisation studies demonstrated that immunity induced by MVA-VP2 was associated with pre-challenge VNAb titres in the vaccinates. Analyses of the inoculum of these MVA-VP2 experimental vaccines showed that they contained pre-formed AHSV-VP2. We continued studying the influence of pre-formed AHSV-VP2, present in the inoculum of MVA-VP2 vaccines, in the immunogenicity of MVA-VP2 vaccines. Thus, we compared correlates of immunity in challenged mice that were previously vaccinated with: a) MVA-VP2 (live); b) MVA-VP2 (live and sucrose gradient purified); c) MVA-VP2 (UV light inactivated); d) MVA-VP2 (UV light inactivated and diluted); e) MVA-VP2 (heat inactivated); f) MVA-VP2 (UV inactivated) + MVA-VP2 (purified); g) MVA-VP2 (heat inactivated) + MVA-VP2 (purified); and h) wild type-MVA (no insert). The results of these experiments showed that protection was maximal using MVA-VP2 (live) vaccine and that the protection conferred by all other vaccines correlated strongly with the levels of pre-formed AHSV-VP2 in the vaccine inoculum

Containment of a fatal and highly infectious disease outbreak

This case study was designed based on several experience with several viral haemorrhagic fevers (VHFs) outbreaks responded to in Uganda between 2000 and 2016. Fictitious scenarios have been included to facilitate learning of the users. The major goal of the case study is to facilitate learners to appreciate incident detection and the incident management processes for control and containment of a fatal and highly infectious viral disease outbreak. This case study is targeted towards health scientists of medicine, nursing, biomedical laboratory and public health background. We specifically orient learners on clinical presentation of viral infections and laboratory tests considered for incident detection, conducting a risk assessment for an infectious disease, Infection Prevention and Control in the outbreak setting, skills of incident management, analysis and interpretation of epidemiological data to aid epidemic response and control decisions

Antiserum from mice vaccinated with modified vaccinia Ankara virus expressing African horse sickness virus (AHSV) VP2 provides protection when it is administered 48h before, or 48h after challenge

AbstractPrevious studies show that a recombinant modified vaccinia Ankara (MVA) virus expressing VP2 of AHSV serotype 4 (MVA-VP2) induced virus neutralising antibodies in horses and protected interferon alpha receptor gene knock-out mice (IFNAR −/−) against challenge. Follow up experiments indicated that passive transfer of antiserum, from MVA-VP2 immune donors to recipient mice 1h before challenge, conferred complete clinical protection and significantly reduced viraemia.These studies have been extended to determine the protective effect of MVA-VP2 vaccine-induced antiserum, when administered 48h before, or 48h after challenge. In addition, passive transfer of splenocytes was undertaken to assess if they confer any degree of immunity to immunologically naïve recipient mice. Thus, antisera and splenocytes were collected from groups of mice that had been vaccinated with MVA-VP2, or wild type MVA (MVA-wt), for passive immunisation of recipient mice. The latter were subsequently challenged with AHSV-4 (together with appropriate vaccinated or unvaccinated control animals) and protection was assessed by comparing clinical signs, lethality and viraemia between treated and control groups. All antiserum recipients showed high protection against disease (100% survival rates even in mice that were immunised 48h after challenge) and statistically significant reduction or viraemia in comparison with the control groups. The mouse group receiving splenocytes from MVA-VP2 vaccinates, showed only a 40% survival rate, with a small reduction in viraemia, compared to those mice that had received splenocytes from MVA-wt vaccinates. These results confirm the primarily humoral nature of protective immunity conferred by MVA-VP2 vaccination and show the potential of administering MVA-VP2 specific antiserum as an emergency treatment for AHSV

Field-Reassortment of Bluetongue Virus Illustrates Plasticity of Virus Associated Phenotypic Traits in the Arthropod Vector and Mammalian Host In Vivo

Reassortment between virus strains can lead to major shifts in the transmission parameters and virulence of segmented RNA viruses, with consequences for spread, persistence, and impact. The ability of these pathogens to adapt rapidly to their environment through this mechanism presents a major challenge in defining the conditions under which emergence can occur

VoiceCoach: Interactive evidence-based training for voice modulation skills in public speaking

The modulation of voice properties, such as pitch, volume, and speed, is crucial for delivering a successful public speech. However, it is challenging to master different voice modulation skills. Though many guidelines are available, they are often not practical enough to be applied in different public speaking situations, especially for novice speakers. We present VoiceCoach, an interactive evidence-based approach to facilitate the effective training of voice modulation skills. Specifically, we have analyzed the voice modulation skills from 2623 high-quality speeches (i.e., TED Talks) and use them as the benchmark dataset. Given a voice input, VoiceCoach automatically recommends good voice modulation examples from the dataset based on the similarity of both sentence structures and voice modulation skills. Immediate and quantitative visual feedback is provided to guide further improvement. The expert interviews and the user study provide support for the effectiveness and usability of VoiceCoach.Comment: Accepted by CHI '2

Memoria 1992

El Consejo Superior de Investigaciones Científicas presenta a través de este documento su memoria de actividades correspondiente al año de 1992. Como en otras ocasiones, se trata de dar a conocer los aspectos más importantes que reflejan el füncionamiento de la Institución durante ese periodo y los cambios que se han producido durante el mismo. Las características que tiene el CSIC como Organismo Público de Investigación hacen que uno de los rasgos más importantes de su funcionamiento sea el de la continuidad en la ejecución de investigación de alta calidad, que es su objetivo básico. Se trata de un Organismo en el que trabajan más de 7000 personas, que cuenta con 89 centros distribuidos por toda España y un presupuesto de alrededor de 46.000 millones de pesetas, de los que casi un 34 % se han generado por los proyectos, contratos y otras actividades que se desarrollan en el seno de la Institución. Además, tuvo la responsabilidad de la formación de 1800 becarios de investigación y del desarrollo de 218 cursos de especialización y doctorado a los que han asistido un considerable número de alumnos. El Consejo es un Organismo cuya vitalidad hace que, año tras año, sea necesario introducir aquellos cambios que puedan contribuir a la mejor consecución de sus objetivos. En este sentido, durante 1992 se ha intensificado la política de realización de evaluaciones externas de los centros, instrumento que cada vez se demuestra más útil para ayudar a la actualización de las lineas de investigación y elevación de su nivel de calidad, afrontando en ocasiones la reestructuración de los centros cuando ésta se estima necesaria. También se han intensificado los esfuerzos para aumentar la participación del Consejo en los programas comunitarios de investigación y desarrollo.Durante 1992, han quedado ultimados los trabajos de consulta y preparación del nuevo Reglamento de Organización y Funcionamiento del Organismo. Con él se ha adaptado su estructura y régimen de funcionamiento al modelo de planificación y coordinación del sistema español de 1+0, previsto en la Ley de Fomento y Coordinación General de la Investigación Científica y Técnica. Se ha aprovechado esta ocasión para introducir algunos cambios en aspectos que, de acuerdo con la experiencia que se tenía del Reglamento anterior, convenia modificar. En este sentido el nuevo Reglamento respeta la participación del personal en la Junta de Gobierno y otros órganos de dirección, refuerza el papel de los Directores de Centros e Institutos, crea un nuevo Comité Clentifico Asesor de carácter permanente, regula las Areas Científico- Técnicas como Instancias de planificación y coordinación de la actividad investigadora y prevé una amplia gama de posibilidades institucionales de colaboración con las Universidades y otros Organismos Públicos de Investigación. El proyecto de nuevo Reglamento quedó ultimado a finales de 1992 y se remitió en esas fechas al Ministerio de Educación para su aprobación y publicación en el Boletín Oficial del Estado. El Organismo ha mantenido durante el año un suave crecimiento. La oferta pública de empleo, planificada a finales de 1992 para su inclusión en los Presupuestos Generales de 1993, autorizaba al Organismo a convocar 181 plazas El número de contratos de investigación se incrementó en un 8,5 % respecto a 1991 y los ingresos derivados de los mismos crecieron en igual proporción. El número de contratos firmados con la Comunidad Europea se incrementó en un 63 % respecto a 1991, resultado del esfuerzo que se está haciendo para concurrir cada vez en mayor número y con más competitividad a los programas comunitarios. Finalmente, durante el año se consiguió financiación de los fondos nacionales para 921 proyectos de investigación por un valor de algo más de 3.000 millones de pesetas. El esfuerzo inversor se vio reforzadoPeer reviewe

Quality assurance of diatom counts in Europe: towards harmonized datasets

Investigations on organism ecology, biodiversity and biogeography often use large compiled datasets to extract information on species ecological preferences, which then can be used in environmental assessment. Freshwater benthic diatoms are commonly used in this context. However, it is important that the taxonomic information of the separate diatom datasets is compatible. At present, inconsistencies between diatom datasets, mainly due to differences and uncertainties in diatom identification, may misinform diatom taxon-specific ecological preferences, geographical distribution and water quality assessment. It is our opinion that these inconsistencies in diatom datasets can be reduced with quality assurance (QA), such as identification exercises. However, the results of these exercises must be well documented and well communicated; otherwise, gained knowledge may not spread inter-regionally or internationally. As a first step to reach greater consistency in QA/harmonization studies, this article (1) presents and compares information of existing diatom identification and counting QA from published and grey (non-peer reviewed) European literature to identify advantages and drawbacks of each approach; (2) summarizes taxa that can easily be misidentified according to European identification exercises; and (3) suggests a consistent design of identification exercises for diatom dataset QA

Diversity of transmission outcomes following co-infection of sheep with strains of bluetongue virus serotype 1 and 8

Bluetongue virus (BTV) causes an economically important disease, bluetongue (BT), in susceptible ruminants and is transmitted primarily by species of Culicoides biting midges (Diptera: Ceratopogonidae). Since 2006, northern Europe has experienced multiple incursions of BTV through a variety of routes of entry, including major outbreaks of strains of BTV serotype 8 (BTV-8) and BTV serotype 1 (BTV-1), which overlapped in distribution within southern Europe. In this paper, we examined the variation in response to coinfection with strains of BTV-1 and BTV-8 using an in vivo transmission model involving Culicoides sonorensis, low passage virus strains, and sheep sourced in the United Kingdom. In the study, four sheep were simultaneously infected using BTV-8 and BTV-1 intrathoracically inoculated C. sonorensis and co-infections of all sheep with both strains were established. However, there were significant variations in both the initiation and peak levels of virus RNA detected throughout the experiment, as well as in the infection rates in the C. sonorensis that were blood-fed on experimentally infected sheep at peak viremia. This is discussed in relation to the potential for reassortment between these strains in the field and the policy implications for detection of BTV strains