Teaching intervention to enhance HIV infection awareness in a biomedical science degree

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Condom use remains the predominant prophylactic intervention to control rates of human immunodeficiency virus (HIV) infection. However, chemoprophylactic strategies, which involve pre-exposure prophyaxis (PrEP) and post-exposure prophyaxis (PEP), have emerged as appropriate prevention tools to minimise and prevent future infections. Different studies have indicated that PrEP can prevent new HIV infections among men who have sex with men when used daily or event-based, and it is also effective with heterosexuals and people who inject drugs. However, appropriate education is needed as recent reports have observed a decline in adherence to PrEP over time, particularly in young adults, which will impact on the effectiveness of PrEP. Thus, we created a brief educational short intervention (3 hours) to increase the awareness of HIV with second year BMedSci Medical Science (Hons) students at De Montfort University (DMU, UK) in 2016/17 (Peña-Fernández et al., 2017). Briefly, BMedSci students tailored a community-centred intervention programme to reduce HIV infection rates following evidence-based public health methodology. 92% indicated an acquisition of knowledge for preventing HIV transmission and tools to fight this disease. However, BMedSci students also showed a lack of knowledge of preventative measures (PrEP and PEP), routes of transmission and appropriate screening. We implemented a similar teaching strategy with BSc Biomedical Science (BMS) students enrolled in the level 4 module of Basic Microbiology in 2017/18, but limited to two hours: one-hour lecture and one hour workshop in which different HIV prevention strategies were discussed and analysed by students. BMS students were also provided with an overview about the Joint United Nations Programme on HIV/AIDS (UNAIDS) 90:90:90 targets in the UK (2016). In a similar way as with the BMedSci cohort, BMS students showed little awareness about PEP/PrEP, specifically knowledge about what are they/how they work, access and usage. This teaching intervention was well-received by students according to the feedback provided in the final module level feedback. BMS participants (n=27 out of 187 students) indicated that they enjoyed the session and suggested a practical session and the introduction of case studies to enhance the teaching intervention. We are developing a virtual clinical case study on HIV following recent successful experiences in the development and introduction of these novel learning strategies and have performed small modifications in the delivery of this workshop for 2018/19 to increase engagement and interaction. In conclusion, we consider that similar short education interventions that specifically target HIV chemoprophylaxis would be needed in any degree to prevent the decline in adherence to PrEP over time observed in young adults and reduce PEP/PrEP stigma and other barriers which could impede their access

Multi-Sensor System For Level Measurements With Optical Fibres

A system for measuring liquid level in multiple tanks using optical fibre technology has been developed. The oil field service industry can benefit from this intrinsically safe technology. Plastic optical fibre (POF) sensor heads are excited by a 650 nm laser. Laser diodes are housed in ST connectors to obtain compact and rough prototypes and these connectors are also used in the fibre pigtails. Optical multiplexing is used to increase the measuring safety area. POF splitters and connectors are used to combine all the receiving sensor head fibres in a single one. Frequency division multiplexing is used to address each sensor head. The global system is controlled through a user friendly software application running in a PC connected to the system via an RS-232 port. A scalable prototype with a range greater than 2 meter, good linearity, better than 1.5% FS (full scale), high accuracy and resolution is developed using a unique lens to collimate and focus the light. Measurements are taken to validate the designs. Up to 8 sensor heads can be connected in the present implementation. But a greater number of sensors can be allocated with minor modifications in the electronics.Universidad Carlos III de MadridPublicad

A non-resonant dark-side solution to the solar neutrino problem

We re-analyse spin-flavour precession solutions to the solar neutrino problem in the light of the recent SNO CC result as well as the 1258--day Super-Kamiokande data and the upper limit on solar anti-neutrinos. In a self-consistent magneto-hydrodynamics approach the resulting scheme has only 3 effective parameters: $\Delta m^2$, $\mu B_\perp$ and the neutrino mixing angle $\theta$. We show how a rates-only analysis for fixed $\mu B_\perp$ slightly favours spin-flavour precession (SFP) solutions over oscillations (OSC). In addition to the resonant solution (RSFP for short), there is a new non-resonant solution (NRSFP) in the ``dark-side''. Both RSFP and NRSFP lead to flat recoil energy spectra in excellent agreement with the latest SuperKamiokande data. We also show that in the presence of a neutrino transition magnetic moment of $10^{-11}$ Bohr magneton, a magnetic field of 80 KGauss eliminates all large mixing solutions other than the so-called LMA solution.Comment: 12 pages, 3 postscript figures, using elsart.cls. Published versio

Localisation effects on the Vibron Shifts in Helium-Hydrogen Mixtures

The vibrational frequency of hydrogen molecules has been observed to increase strongly with He concentration in helium hydrogen fluid mixtures. This has been associated with He-H interactions, either directly through chemical bonding, or indirectly through increased local pressure. Here, we demonstrate that the increase in the Raman frequency of the hydrogen molecule vibron is due to the number of H$_2$ molecules participating in the mode. There is no chemical bonding between He and H$_2$, helium acts only to separate the molecules. The variety of possible environments for H$_2$ gives rise to many Raman active modes, which causes broadening the vibron band. As the Raman active modes tend to be the lower frequency vibrons, these effects work together to produce the majority of the shift seen in experiment. We used Density Functional Theory (DFT) methods in both solid and fluid phases to demonstrate this effect. DFT also reveals that the pressure in these H$_2$-He mixture is primarily due to quantum nuclear effects, again the weak chemical bonding makes it a secondary effect

Differential contribution of PB1-F2 to the virulence of highly pathogenic H5N1 influenza A virus in mammalian and avian species

Highly pathogenic avian influenza A viruses (HPAIV) of the H5N1 subtype occasionally transmit from birds to humans and can cause severe systemic infections in both hosts. PB1-F2 is an alternative translation product of the viral PB1 segment that was initially characterized as a pro-apoptotic mitochondrial viral pathogenicity factor. A full-length PB1-F2 has been present in all human influenza pandemic virus isolates of the 20(th) century, but appears to be lost evolutionarily over time as the new virus establishes itself and circulates in the human host. In contrast, the open reading frame (ORF) for PB1-F2 is exceptionally well-conserved in avian influenza virus isolates. Here we perform a comparative study to show for the first time that PB1-F2 is a pathogenicity determinant for HPAIV (A/Viet Nam/1203/2004, VN1203 (H5N1)) in both mammals and birds. In a mammalian host, the rare N66S polymorphism in PB1-F2 that was previously described to be associated with high lethality of the 1918 influenza A virus showed increased replication and virulence of a recombinant VN1203 H5N1 virus, while deletion of the entire PB1-F2 ORF had negligible effects. Interestingly, the N66S substituted virus efficiently invades the CNS and replicates in the brain of Mx+/+ mice. In ducks deletion of PB1-F2 clearly resulted in delayed onset of clinical symptoms and systemic spreading of virus, while variations at position 66 played only a minor role in pathogenesis. These data implicate PB1-F2 as an important pathogenicity factor in ducks independent of sequence variations at position 66. Our data could explain why PB1-F2 is conserved in avian influenza virus isolates and only impacts pathogenicity in mammals when containing certain amino acid motifs such as the rare N66S polymorphism

Evolution annuelle du peuplement zooplanctonique dans un lagunage à haut rendement et incidence du temps de séjour

Proposé au début des années soixante par W.J. OSWALD, le lagunage dit « à haut rendement », utilisé pour l'épuration d'eaux usées domestiques, représente un écosystème hypereutrophe. Il se distingue considérablement du lagunage naturel par des temps de séjour très courts (2 à 12 jours), de très faibles profondeurs (< 1 m) et par une agitation constante de façon à favoriser le développement algal.Cette étude a pour objectifs de : 1) caractériser les successions saisonnières du zooplancton dans un écosystème où celles-ci n'ont pratiquement pas été étudiées et 2) étudier l'impact, sur la structure du peuplement et au fil des saisons, du temps de séjour des eaux à traiter.Le suivi du peuplement zooplanctonique a été réalisé pendant une période de deux ans dans deux bassins à haut rendement (nommés A et B) de même configuration alimentés en eaux usées. Les temps de résidence des eaux à traiter sont constants et de huit jours dans l'un, variable et ajusté selon l'ensoleillement et la charge entrante dans l'autre.Les résultats obtenus sont analysés par une classification hiérarchique avec contrainte de contiguïté temporelle. Les groupes obtenus sont ensuite testés par l'analyse discriminante. Les résultats sont regroupés chronologiquement : en six groupes pour le bassin B et en dix groupes pour le bassin A. L'analyse discriminante montre que les Crustacés et les Rotifères sont respectivement responsables des regroupements dans les bassins B et A. Pendant la période de démarrage du lagunage ainsi qu'en automne et en hiver, le zooplancton est principalement composé de Protozoaires : Ciliés libres ou fixés en fortes densités (jusqu'à 2,7.107 ind. 1-1) et Rhizopodes (Amibes). Au printemps et en été, lorsque le rayonnement solaire devient important, la production primaire étant optimale, les Protozoaires sont remplacés par des brouteurs herbivores métazoaires. La production de Rotifères et de Daphnies dont les exigences en nourriture (microalgues) sont considérables est importante au printemps ou bien en été uniquement dans le bassin à temps de séjour court. Le développement des Crustacés Copépodes et Ostracodes est favorisé en été dans le bassin à temps de séjour plus long.Tous ces organismes participent activement à réparation. ils se nourrissent pour la plupart en filtrant les éléments en suspension dans le milieu et participent directement à l'élimination des MES et de la DCO (PIZAY-PARENTY, 1985).II devient donc envisageable, par suite du rôle non négligeable joué par le zooplancton et surtout par Daphnia magna, de concevoir une gestion du lagunage qui favoriserait le développement de ce Cladocère. Cette biomasse facilement récupérable par tamisage peut être valorisée en aquaculture.High rate ponds for wastewater treatment have been the focus of much attention since their creation by W.J. OSWALD in the early 1960's. These aquatic ecosystems are hypereutrophic because of massive nutrient introduction by wastewater influents. These kinds of ponds are very different front natural biological ponds because of short residence times (2 to 12 days), shallow depths (<1 m) and constant mechanical mixing which improve alga : growth.This study presents the following objectives : 1) to characterize seasonal successions of zooplankton in this ecosystem where they are unknown and 2) to study residence time influence on zooplanktonic successions in function of seasons. Our investigation consists in studying two similar high rate ponds of 48 m2 surface area and 35 cm depth constantly stirred by paddle wheels.Only residence time is different. The first pond has eight days residence time and in the second one, it changes with solar radiations and organic matter concentrations. The influents come from a primary pond of eight days residence time, fed continuously with domestic influents front a small town, Mèze. The aim of this experiment is to compare seasonal successions in these two high rate ponds (called A and B) with different residence times. Zooplanktonic investigation has been carried out for two years. One sample was collected twice a week in primary pond effluent and two others samples collected once a week into the two high rate ponds near the outflow areas. The results of chronological clustering take inter account the discontinuities of zooplanktonic structure. We obtain six sequences in B pond and ten groups in A pond. Stepwise discriminant analysis shows that Crustaceans and Rotifers are respectively responsible for chronological clustering in B and in A pond. During the sterling period of wastewater treatment and in autumn and in winter, photosynthesis is low and zooplankton is composed mainly of Protozoa : free-living or fixed Ciliates in great concentrations (until 2,7.107 ind. l-1) and Rhizopods (Amæba sp.). These organisms have important food needs (bacteria and algal detritus). During spring and summer, as solar radiations become important, Protozoa are replaced by metazoan grazers. Spring or summer with short residence times increase Rotifers or Daphnia magna production white summer with longer residence times increase Cyclops sp and cypris ovum production. All these organisms are active components of wastewater treatment : the consumption of particulates by zooplankton Increases TSS and COD removal efficiencies (PIZAY-PARENTY, 1985).Therefore, because of the filtering activity of Crustaceans (especially of Daphnia magna), it seems possible to conceive a new pond managment, with residence time changes, favourable to exponential algal growth and consequently to crustacean biomass production. It is easier to harvest this biomass (with nets) than to harvest algal biomass, which still presents problems

Temporal Electrical Response of V/W-shaped Chiral Smectic Liquid Crystal Displays

Chiral smectic liquid crystal cells showing V-shaped electrooptical switching have been reported as one of the most promising technologies for high-end display applications. In this work, time-resolved electrical behaviour of these devices has been obtained through a set of systematic measurements. The electrical equivalent circuit has been derived, a number of simulations at different frequencies have been performed using commercial software for analogue circuits. Performance of this electrical model to account for time domain variations of switching currents in chiral smectic LC displays with V/W-shaped electrooptical response has been analyzed as well

Elimination de l'azote et du phosphore dans un lagunage à haut rendement

L'objectif de cette étude est de comprendre le fonctionnement épuratoire de l'écosystème particulier que constitue le lagunage à haut rendement (LHR) afin de déterminer les principaux facteurs responsables de l'élimination de l'azote et du phosphore.Sur un bassin de 48 m2, alimenté eu eaux usées domestiques préalablement traitées pendant une semaine dans un bassin primaire ont été suivies selon un rythme hebdomadaire les formes carbonées, azotées et phosphorées dis-soutes et particulaires, les variables caractéristiques de l'activité photosynthétiques (chlorophylle a, pH et 02) et les données climatiques (rayonnement solaire et température). Une analyse en composantes principales réalisée sur l'ensemble des résultats a montré, d'une part l'opposition des variables climatiques et photosynthétiques aux formes minérales de l'azote et du phosphore (N-NH4 et P-PO4) et d'autre part l'influence de la charge organique sur le fonctionnement du système.L'évolution des formes azotées et phosphorées présente un effet saisonnier marqué. En hiver ou lors de surcharge organique importante, une augmentation du temps de séjour peut améliorer les rendements épuratoires. L'évolution de la matière organique dissoute est indépendante du cycle saisonnier. Au cours des deux années du suivi on observe une adaptation progressive de l'écosystème à la dégradation de la matière organique.Dans le lagunage à haut rendement l'élimination de l'azote et du phosphore est liée principalement à l'activité algale, qui entraîne une assimilation biologique et une élévation du pH, responsables des phénomènes chimiques de volatilisation de l'azote ammoniacal et de précipitation de phosphate de calcium.High rait algal ponds (HRAP) for wastewater treatment have been the locus of a lot of attention since their creation by Professor W.J. OSWALD in the early 1960' s. These aquatic ecosystems are hypereutrophic because of massive nutrient introduction with the wastewater influent. This kind of pond is very different from oxidation ponds because al short residence times (2 to 12 days), shallow depths (0.30 to 0.60 m) and constant mechanical mixing which improves algal growth.This study has been carried out in a small town in the department of Herault (France). The objective is to establish the efficiencies and mechanisms for nitrogen and phosphorus remval from secondary domestic wastewater by treatment by HRAP. A high rate algal pond of 48 m2 surface area and 35 cm depth, constantly mixed with paddle wheels was studied (fig. 1). Residence limes changed from 2 te 12 days with solar radiations and influent loading. The samples were collected once a week from the in- and outflow at 3 p.m. - Dissolved and particulate COD, varions nitrogen and phosphorus compounds, suspended solide, chlorophyll-a, pH, dissolved oxygen, temperature and irradiation were determined.The results of principal component analysis show a negative correlation between (1) the climatic and photosynthetic parameters and (2) inorganic nitrogen and phosphorus compounds, as well as the influence of organic loading on the HRAP efficiency.The chronological clustering analysis was performed on the data taking into account the discontinuities of effluent autrient contents (fig. 4). During the first year, from February to September 1988, good climatic conditions were shown to favour photosynthetic activity and consequently a good ammonia and orthophosphate removal. Front September 1988 to February 1989, the effluent was characterized by high ammonia and orthophosphate levels because of unfavourable climatic conditions and low photosynthetic activity. During the second year, the objective was to improve removal efficiencies ; the residence time was changed with solar radiations and influent loading. The results of the chronological clustering analysis of ammonia and orthophosphate levels showed only one sequence (February 1989-January1990) because the seasonal variations of nutrient removal were attenuated. The optimal residence time was found to be 4 days in summer and 12 days in winter.The evolution of dissolved chemical oxygen demand is independent of seasonal conditions but decreases with the maturity of the system (< 50 mg . l-1).The mass balance of nitrogen and phosphorus compounds has been established (fig. 5). In high rate algal pond influent, the main nitrogen form is ammonia. In the effluent the main nitrogen form is suspended organic nitrogen. The oxidized forms (NO2- et NO3) present very low levels ; nitrification is a minor process in the system. Ammonia is reduced by both assimilation and stripping ; suspended organic nitrogen in the effluent is an indicator of assimilation by algal biomass and loss of nitrogen is an indicator of ammonia stripping. With regard to directive 91/271 EEC concerning domestic wastewater treatment, partial algal separation is necessary in order to achieve 15 mg • l-1 total nitrogen, which is the limit for zones sensitive to eutrophication.The residual phosphate levels are controlled by pH, which is responsible for instantaneous calcium phosphate precipitation. As the dissolved calcium concentrations are high in the calcareous region near the site (Ca = 125 mg • l-1), the pH of the water will be the main contraint on phosphate elimination in the HRAP. Theoretical calculations indicate that the precipitate is probably an amorphous tricalcium phosphate in pseudoequilibrium (fig.6). Phosphate concentrations are much higher titan the values expected for calcium hydroxyapatite in equilibrium (MOUTIN et al., 1992). The limit of 2 mg • l-1 for phosphores can only be attained when pH reaches or exceeds 9.Nitrogen and phosphorus removal is correlated mainly with phytoplanktonic activity, which controls biological nutrients assimilation and pH levels. High pH values are responsable for ammonia stripping and calcium phosphate precipitation