Immunotherapy approach to combat nicotine addiction

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Cloud service data collection for cloud service selection

Data collection for cloud DSS tools is a huge challenge not only because of the lack of integration of quality of experience with existing cloud data but also by not having a holistic view of security characteristics in cloud. We solve it by using crowdsourcing techniques&providing a security V too

Teachers’ vs. learners’ communicative strategies in EFL classes

Communicative competence and awareness of communicative strategies are vital factors in EFL learning. Due to their importance, this study aimed to investigate the strategies used by EFL teachers and learners. To this end, 10 teachers were randomly selected. One hundred fifty EFL learners attending these classes were also subjected to the study. The utterances produced by participants were recorded, transcribed, and coded based on Dornyei’s taxonomy (1995). A mixed-method approach entailing both qualitative and quantitative analysis was taken. The findings indicated that while compensatory strategy was the most frequently used strategy (54%) by EFL learners, stalling or time gaining strategy was the least frequently used one (19%) with the avoidance communicative strategy (27%) placed between them., EFL teachers, however, employed the strategy of stalling or time gaining most frequently (63%), while the strategy of avoidance was the least frequently used strategy (11%) by the EFL teachers after the compensatory communicative strategy (26%). Finally, in further analysis, the results of the chi-square test demonstrated a significant difference between teachers’ and learners’ strategy use frequency. Language teachers need to be aware of the type and frequency of effective communicative strategies used by their learners to raise their consciousness about the appropriate use of efficient strategies. Teacher trainers can help these teachers with the proper means of initiating and maintaining classroom interactions to foster the communicative and strategic competencies of their learners. Material developers need to take these findings into account in course content preparation to improve strategy use among language learners

'A true partner around the table?' Perceptions of how to strengthen public health's contributions to the alcohol licensing process

Introduction: There are increased opportunities for public health practitioners (PHPs) in England to shape alcohol availability and reduce harms through a statutory role in licensing processes in local government. However, how public health can effectively influence alcohol licence decision-making is little understood. Methods: A mixed methods study was conducted to identify challenges faced by PHPs and mechanisms to strengthen their role. This involved a survey of practitioners across London local authorities (n = 18) and four focus group discussions with a range of licensing stakeholders (n = 36). Results: Survey results indicated a varied picture of workload, capacity to respond to licence applications and levels of influence over decision-making among PHPs in London. Practitioners described a felt lack of status within the licence process, and difficulties using and communicating public health evidence effectively, without a health licensing objective. Strategies considered supportive included engaging with other responsible authorities and developing understanding and relationships over time. Conclusions: Against political and resource constraints at local and national government levels, pragmatic approaches for strengthening public health influence over alcohol licensing are required, including promoting relationships between stakeholders and offering opportunities for PHPs to share best practice about making effective contributions to licensing

Processes, practices and influence: a mixed methods study of public health contributions to alcohol licensing in local government

Background: Public health in England has opportunities to reduce alcohol-related harms via shaping the availability and accessibility of alcohol through the licensing function in local government. While the constraints of licensing legislation have been recognised, what is currently little understood are the day-to-day realities of how public health practitioners enact the licensing role, and how they can influence the local alcohol environment. Methods: To address this, a mixed-methods study was conducted across 24 local authorities in Greater London between 2016 and 17. Data collection involved ethnographic observation of public health practitioners' alcohol licensing work (in eight local authorities); a survey of public health practitioners (n = 18); interviews with licensing stakeholders (n = 10); and analysis of public health licensing data from five local authorities. Fieldnotes and interview transcripts were analysed thematically, and quantitative data were analysed using descriptive statistics. Results: Results indicated that some public health teams struggle to justify the resources required to engage with licensing processes when they perceive little capacity to influence licensing decisions. Other public health teams consider the licensing role as important for shaping the local alcohol environment, and also as a strategic approach for positioning public health within the council. Practitioners use different processes to assess the potential risks of licence applications but also the potential strengths of their objections, to determine when and how actions should be taken. Identifying the direct influence of public health on individual licences is challenging, but the study revealed how practitioners did achieve some level of impact, for example through negotiation with applicants. Conclusions: This study shows public health impact following alcohol licensing work is difficult to measure in terms of reducing alcohol-related harms, which poses challenges for justifying this work amid resource constraints. However, there is potential added value of the licensing role in strategic positioning of public health in local government to influence broader determinants of health

Breadth of the CD4+ T cell response to Anaplasma marginale VirB9-1, VirB9-2 and VirB10 and MHC class II DR and DQ restriction elements

MHC class II molecules influence antigen-specific CD4(+) T-lymphocyte responses primed by immunization and infection. CD4(+) T-cell responses are important for controlling infection by many bacterial pathogens including Anaplasma marginale, and are observed in cattle immunized with the protective A. marginale outer membrane (OM) vaccine. Immunogenic proteins that comprise the protective OM vaccine include type IV secretion system (T4SS) proteins VirB9-1, VirB9-2, and VirB10, candidates for inclusion in a multi-epitope vaccine. Our goal was to determine the breadth of the VirB9-1, VirB9-2, and VirB10 T-cell response and MHC class II restriction elements in six cattle with different MHC class II haplotypes, defined by DRB3, DQA, and DQB allele combinations for each animal. Overlapping peptides spanning each T4SS protein were tested in T-cell proliferation assays with autologous antigen presenting cells (APC) and artificial APC expressing combinations of bovine DR and DQ molecules. Twenty immunostimulatory peptides were identified; three representing two or more epitopes in VirB9-1, ten representing eight or more epitopes in VirB9-2, and seven representing seven or more epitopes in VirB10. Of eight DRA/DRB3 molecules, four presented 15 peptides, which was biased as DRA/DRB3*1201 presented ten and DRA/DRB3*1101 presented four peptides. Four DQA/DQB molecules composed of two intrahaplotype and two interhaplotype pairs presented seven peptides, of which five were uniquely presented by DQ molecules. In addition,three functional mixed isotype (DQA/DRB3) restriction elements were identified. The immunogenicity and broad MHC class II presentation of multiple VirB9-1, VirB9-2, and VirB10 peptide epitopes justify their testing as a multi-epitope vaccine against A. marginale

Nage des algues motiles dans un écoulement oscillant

Alors que nombreuses études ont été menées sur l'hydrodynamique de micro-organismes motiles soumis à des écoulements cisaillés en régime stationnaire ; l'écoulement oscillant a reçu très peu d'attention. Dans ce travail, nous étudions la nage et le transport de Chlamydomonas reinhardtii, qui est une algue phototactique modèle, dans un écoulement oscillant cisaillé. L'écoulement sinusoïdal est généré à l'aide d'un système microfluidique qui pilote la pression. Trois microcanaux de sections rectangulaires de hauteurs identiques et de largeurs différentes ont été utilisés. Le débit a été exprimé par Flow rate( t )=A .sin( ωt ) où t, A et ω représentent respectivement le temps, l'amplitude et la fréquence angulaire d'oscillation. Différentes amplitudes (A=0,075, 0,15, 0,22, 0,3 et 0,5 µl/min) et fréquences d'oscillation (f= 0,5, 1, 2 et 3,3 Hz) ont été appliquées. La première partie de l'étude s'est concentrée sur la migration latérale des cellules dans les écoulements stationnaires et sinusoïdaux. Les trajectoires de cellules ont été caractérisées pour ces deux régimes d'écoulement. Il a été montré que la dynamique des algues dans l'écoulement stationnaire varie d'un mouvement semi-Brownien à un mouvement en forme de zigzag selon la vitesse d'écoulement (taux de cisaillement). En augmentant la vitesse d'écoulement, une diminution de l'angle entre les trajectoires et la direction d'écoulement a été observée. Lorsque l'écoulement est devenu sinusoïdal, les cellules ont commencé à nager perpendiculairement à la direction de l'écoulement ; d'une paroi latérale à la paroi opposée en suivant des trajectoires ondulées. Chaque trajectoire avait une forme sinusoïdale en particulier au cœur du microcanal où l'effet de couche limite est faible. Après avoir atteint une paroi, les cellules ont passé un court moment à glisser ou à s'y coller avant de repartir vers la paroi opposée en suivant toujours des trajectoires ondulées. Une corrélation entre les longueurs d'onde des trajectoires et les paramètres d'oscillation (amplitudes et fréquences de l'écoulement) a été déterminée. Ensuite, le comportement phototactique de Chlamydomonas reinhardtii au sein d'une suspension oscillante a été étudié. Deux LEDs ont été placées à côté d'une des parois latérales d'un long microcanal de section rectangulaire (largeur = 500 m, hauteur = 85 m). En ce qui concerne les effets à court terme de l'exposition à la lumière, il a été montré que si la période d'oscillation de l'écoulement est plus courte que le temps de réponse des algues à la lumière (environ 1 seconde), les cellules ne réagissent pas immédiatement à la lumière. Ainsi, le pourcentage de cellules présentant une phototaxie négative (Nup) augmente plus lentement par rapport aux cas où la période d'oscillation est suffisamment longue (basses fréquences). Concernant les effets à long terme de la lumière, les résultats ont montré que le comportement phototactique des algues varie en fonction du temps et que cette variation est différente pour les suspensions de faibles et de hautes concentrations. Pour les suspensions de faibles concentrations, Nup augmente au début de chaque cycle d'exposition à la lumière jusqu'à atteindre un pic; puis il diminue jusqu'à la valeur initiale indiquant que l'effet de la lumière n'est plus perceptible par les cellules. Lorsque ce cycle a été répété après une petite pause (lumière éteinte), une tendance similaire de la variation de Nup mais avec une valeur de crête plus petite a été observée. Cet effet d'amortissement s'est poursuivi en répétant le cycle et finalement les algues ont perdu leur sensibilité à la lumière. Un modèle empirique en bon accord avec les données expérimentales a été proposé pour ce comportement. Il a été expliqué que cet amortissement de la sensibilité à la lumière est dû à une corrélation entre l'adaptation des algues à la lumière et la réadaptation de leur fluorescence chlorophyllienne.While various studies have been conducted on the hydrodynamics of motile microorganisms subjected to steady shear flows; oscillating flow has received much less attention. In this study, we investigate the swimming and transport of the phototactic alga Chlamydomonas reinhardtii in oscillatory shear flows. Sinusoidal flow of algal suspension was generated in the microchannels using a microfluidic pressure-driven controller. Three microchannels of rectangular cross-section with similar heights and different widths were used. The oscillating flow was expressed as Flow rate( t )=A .sin( ωt ) where Flow rate( t ), t, A, and ω, represent the instantaneous flow rate, time, amplitude and angular frequency of the oscillating flow rate, respectively. The different amplitudes considered in the study were A=0.075, 0.15, 0.22, 0.3 and 0.5 µl/min. For each amplitude, four frequencies were applied: f = 0.5, 1, 2 and 3.3 Hz. The focus of the first part of study was on the cross-flow migration of the cells. The characteristics of cell trajectories were determined in both steady and sinusoidal flow conditions. It was shown that the dynamics of the cells in the steady flow varies from a semi-Brownian motion to a zigzag motion depending on the flow velocity (shear rate). By increasing the flow velocity, a decrease in the angle between the trajectories and the flow direction was observed. When the flow condition turned to a sinusoidal flow, the cells started to swim from one lateral wall to the opposite wall in wavy trajectories and perpendicularly to the flow direction. Each trajectory was similar to a sinusoidal-form displacement especially in the central zone of the microchannel where the effect of boundary layer is weak. After reaching the wall, the cells spent a short while sliding on or sticking to it before leaving toward the opposite wall following similar wavy trajectories. The correlation between the wavelengths of the trajectories and the parameters of flow oscillation (amplitudes and frequencies) was determined. In the next part of study, the phototactic behavior of Chlamydomonas reinhardtii was studied in oscillatory flows. Two light-emitting diodes were placed next to one of the lateral walls of a long PDMS microchannel of rectangular cross-section (width = 500 μm, height =85 μm) which was enclosed in a dark box. With respect to the short-term effects of light exposure, it was shown that if the period of flow oscillation is shorter than the response time of the cells to a light stimulus (about 1 second), the cells can not react immediately to the light and thus, the increase in the percentage of cells showing a negative phototaxis (Nup) occurs later compared to the cases where the oscillation period is enough long (low frequencies). Regarding the long-term effects of light exposure, it was shown that the phototactic behavior of the cells is a function of time in both low and high concentrated suspensions; however, this evolution with time depends on the concentration. Over a cycle of light exposure on the dilute suspensions, Nup increases in the beginning until reaching a peak; then it decreases to the initial value indicating that the effect of light is no longer perceptible by the cells. When the light cycle was repeated after a short rest time (light off), a similar trend but with a smaller peak value was observed. This damping effect persisted by repeating the light cycle and finally the cells were no more sensible to the light. An empirical model that fits well the experimental data was proposed for this behavior. It was explained that the decrease in the overall response to the light stimuli is due to a connection between light adaptation of Chlamydomonas reinhardtii cells and readaptation of their chlorophyll fluorescence

Cloud service data collection for cloud service selection

Data collection for cloud DSS tools is a huge challenge not only because of the lack of integration of quality of experience with existing cloud data but also by not having a holistic view of security characteristics in cloud. We solve it by using crowdsourcing techniques&providing a security V too

Accumulation of toxic metals of cadmium and lead in the deciduous teeth of children

Background and Aim: Lead and cadmium are as main environment pollutants, and even in low concentrations have harmful effects on human health. Baby teeth are efficient indicators of environmental exposure of children to heavy metals. The aim of the present study is to determine the concentration of lead and cadmium in deciduous teeth of 5-12 year old girls and boys in Birjand in 2010. Materials and Methods: In this applied research, teeth samples of children were collected from different clinics of Birjand. The samples were prepared by means of acidolysis method and metal levels were measured using graphite furnace atomic absorption spectrophotometer. Data analysis was conducted thanks to SPSS software (version 16) and P<0.05 was taken as the significant level. Results: Mean amount of lead and cadmium in teeth samples was 1.96&plusmn;1.62 and 0.2&plusmn;0.17 &micro;g/g, respectively. The highest levels of lead was found in children&rsquo;s molar teeth, while children&rsquo;s incisor teeth had a higher level of cadmium. Besides, the amount of lead and cadmium was more in the boys' samples rather than the girls'. However, the difference between the two genders was not significant. Conclusion: Deciduous teeth are suitable bio indicators to monitor for environmental pollution with heavy metals. The metal levels of lead and cadmium in the teeth of boys are more than girls'. The main reason is the presence of these metals in the environment and the boys' long-term exposure to these pollutants

Phototactic Behavior of Micro-Swimmers: Light Effects on Cell Swimming in Oscillating Flow

International audienceAbstract In this investigation, the phototactic behavior of the swimmer alga Chlamydomonas reinhardtii was studied in oscillatory flows. Two light-emitting diodes (LED) were placed next to one of the lateral walls of a long PDMS microchannel of rectangular cross-section (width = 500 μm, height = 85 μm) which was enclosed in a dark box. Oscillating flow of algal suspension was generated using a pressure-driven control system. Both low and high concentrations of the cells were considered. The short- and long-term effects of light exposure on the cells swimming, and the influence of amplitude and frequency of flow oscillation in the presence of light stimulus were determined. It was shown that if the period of flow oscillation is shorter than the response time of the cells to a light stimulus (about 1 second), the cells cannot react immediately to the light and thus, the increase in the percentage of cells population showing a negative phototaxis (Nup) occurs later compared to the cases where the oscillation period is long enough (low frequencies). Moreover, it was shown that a smaller oscillation amplitude results in a sharper and earlier increase in Nup since the cells are less affected by the flow advection and respond more efficiently to the light stimulus. Regarding the long-term effects of light exposure, it was shown that the phototactic behavior of the cells is a function of time, in both low and high concentrated suspensions; however, this evolution with time depends on the concentration. Over a cycle of light exposure on the dilute suspensions, Nup increases in the beginning of the cycle until reaching a peak; then it decreases to the initial value indicating that the effect of light is no longer perceptible by the cells