Cognitive transfer of spatial awareness states from immersive virtual environments to reality.

An individual's prior experience will influence how new visual information in a scene is perceived and remembered. Accuracy of memory performance per se is an imperfect reflection of the cognitive activity (awareness states) that underlies performance in memory tasks. The aim of this research is to investigate the effect of varied visual fidelity of training environments on the transfer of training to the real-world after exposure to immersive simulations representing a real-world scene. A between groups experiment was carried out to explore the effect of rendering quality on measurements of location-based recognition memory for objects and associated states of awareness. The immersive simulation, consisted of one room that was either rendered flat-shaded or using radiosity rendering. The simulation was displayed on a stereo head-tracked Head Mounted Display. Post exposure to the synthetic simulation, participants completed a memory recognition task conducted in a real-world scene by physically arranging objects in their physical form in a real world room. Participants also reported one of four states of awareness following object recognition. They were given several options of awareness states that reflected the level of visual mental imagery involved during retrieval, the familiarity of the recollection and related guesses. The scene incorporated objects that 'fitted' into the specific context of the real-world scene, referred to as consistent objects, and objects which were not related to the specific context of the real-world scene, referred to as inconsistent objects. A follow-up study was conducted a week after the initial test. Interestingly, results revealed a higher proportion of correct object recognition associated with mental imagery when participants were exposed to low fidelity flat-shaded training scenes rather than the radiosity rendered ones. Memory psychology indicates that awareness states based on visual imagery require stronger attentional processing in the first instance than those based on familiarity. A tentative claim would therefore be that those immersive environments that are distinctive because of their variation from 'real', such as flat-shaded environments, recruit stronger attentional resources. This additional attentional processing may bring about a change in participants' subjective experiences of 'remembering' when they later transfer the training from that environment into a real-world situation

Ivermectin in the treatment of Bancroftian filariasis infection in Orissa, India

Ivermectin treatment has evaluated for its efficacy and side reactions in sixty patients of Orissa with Bancroftian filarial infection and microfilaremia. Ivermectin was administered as a single oral dose at four dosage levels (20, 50. 100 and 200 μg/kg), and both microfilarial clearance and associated side reactions were monitored in a double blind fashion. Blood microfilariae were cleared in all patients at all dosages within 1 to 14 days. In most patients microfilariae reappeared by third month. The microfilaria appearance by third and sixth month averaged 12.2 to 44 percent of pretreatment values in the fourstudy groups. Side reactions were encountered in almost all patients, the commonest being fever. headache, weakness, myalgia and cough which occured most prominently 12 to 72 hours after treatment. Side reactions were more frequent and severe in patients with high microfilaria counts. Clinical reaction scores for each group were independent of the dose administered. The 200 μg dose group showed significantly more rapid microfilariae clearance and its delayed reappearance as compared with the other dosage groups and without inducing significantly greater clinical reaction scores

Le comportement d'un système hydrologique en climat méditerranéen par l'analyse corrélatoire et spectrale des débits et des pluies. Cas de trois sous bassins sud-méditerranéens : (oued Sebdou, Moulah et Isser - Tafna - NW Algérie)

Les analyses corrélatoire et spectrale des chroniques de la pluie (entrée) et de débits (sortie) journaliers enregistrés au niveau des trois bassins sud méditerranéens Sebdou, Mouilah et Isser durant un seul cycle hydrologique nous ont permis d’obtenir des informations sur le fonctionnement de ces systèmes hydrologiques. Bien que la structure du signal « pluie » semble présenter les mêmes caractéristiques pour les trois bassins, le signal de sortie « débit » indique que l’oued Sebdou réagit différemment par rapport aux oueds Mouilah et Isser.The aim of this work was to show that correlation and spectral analyses can be used to understand the functioning of hydrological systems. Accordingly, a study was carried out on three southern Mediterranean basins: Sebdou; Mouilah and Isser; located in the north western of Algeria. (Figure 1). Correlation and spectral analyses of daily rainfall and discharge rates for one hydrological cycle were carried out.Simple analysisSimple analysis of rainfall showed that the correlograms (Figure 2) decreased rapidly for the three basins, reaching a value of 0.2 within 1-2 days. This result indicated that rainfall was a quasi-random phenomenon. The variance density spectrum (Figure 3) showed that the rainfall distribution was not monotonous and presented a “Leigh” signal structure.The simple analysis of discharge rates indicated that the Sebdou system was different. The correlogram (Figure 4a) decreased quickly, characterising independent events without memory and with non-significant amounts of water. However, the Mouilah and Isser correlograms (Figure 4 b,c) decreased slowly. They represent important memory effects with regulation of significant amounts of water. The spectral band (Figure 5) confirmed that the Sebdou system did not modify the input information. The regulation time was about 5 d for Sebdou, 21 and 43 d respectively for Mouilah and Isser.Cross analysisThe correlograms (Figure 6) show that the Mouilah and Isser rivers have a great buffering ability. The Sebdou River was characterised by a composite response of the surface flow and an important groundwater flow. The amplitude function (Figure 7) indicated that the Sebdou system had good inertia. The lag time (Figure 8) was 9, 2 and 5 days respectively for the Sebdou, Mouilah and Isser rivers. The amplification and attenuation of the input signal (Figure 10) show that the Sebdou basin is the most karstified system. The non-linearity of the relationship between rainfall and discharge was expressed by the coherence coefficient (Figure 9), which was lower than 1

Incidences de pluies exceptionnelles sur un aquifère libre côtier en zone semi-aride (Chaouia, Maroc)

Les eaux souterraines qui représentent les seules ressources en eau de la Chaouia côtière, sont très minéralisées : intrusion marine, évaporation et recyclage des eaux d'irrigation chargées en sels. L'évolution spatio-temporelle piézométrique et hydrochimique de cet aquifère a été observée sur 179 puits, de 1991 à 1998 qui inclue une période exceptionnellement pluvieuse. Une comparaison par rapport à l'état de la nappe en 1971, date du début de l'exploitation des eaux souterraines, a été faite. Les suivis ont montré qu'à la suite des pluies importantes de 1996 (943 mm), un rehaussement important du niveau de la nappe et des dilutions plus ou moins retardées de tous les sels en solution dans l'eau, sont mesurés dans tous les puits. En effet, la nappe qui a accusé des baisses de 10 à 20 m entre 1971 et 1995, remonte en 1996 de 4,5 à 12,5 m en moyenne surtout au centre et à l'amont de la plaine. Quant à la qualité des eaux qui s'était dégradée, elle a connu des améliorations importantes avec des variations de 0,5 à plus de 4 ms/cm au niveau de la conductivité électrique. Ces faits montrent une grande sensibilité de la nappe aux apports par les pluies qui constituent sa principale alimentation.A study of regional pollution in the coastal aquifer system between Oum-er-Rbia River and Bir Jdid (Coastal Moroccan Meseta, Morocco) was based on data gathered from 1995 to 1998. The study improved the hydrogeological and hydrochemical understanding of the aquifers. The study examined the effects of significant rains on the quantity and quality of coastal groundwater. These waters exhibited high sensitivity to the rain input.Measurements undertaken since 1991 on 179 wells in the study area reveal that the groundwaters are highly mineralized - conductivity reaches more than 10 mS/cm, depending on season and well location. These results also show high chloride concentrations (more than 3500 mg/l), sodium concentrations frequently in the 500 - 1000 mg/l range and nitrates between 150 and 250 mg/l.In coastal Chaouia, these high concentrations of dissolved mineral salts aggravate the problem of supplying quality water to the rural population for drinking or even market-gardening irrigation purposes. The area is characterized by increased irrigated surfaces (more than 16000 hectares with 4125 m3 /s) and a demographic rise that has triggered the chaotic boring of more than 2000 wells into a heterogeneous aquifer sensitive to salinity. Possible sources of this high salinity include :Seawater intrusion into coastal aquifer sectors (mainly into a two-kilometre strip of coastline). The degree and the length of the marine intrusion were exacerbated by intensive pumping for irrigation needs, particularly during the dry season. Other factors such as coastal aquifer permeability, saturation zone thickness and basement depth also affect the degree and length of the marine intrusion. Seawater pollution is more marked in the southwestern coastal area.Reuse of irrigation saline waters, especially as groundwater circulates in the coastal and eastern sectors deep in the soil (to depths of 10 m).Several important factors have been highlighted concerning the origin of the chemical elements in solution and the mechanism of hydrochemical distribution: evaporation, lithology of tapped aquifers, water table depth, distance of wells from the coast, type of soil, use of fertilizers, frequency of pumping operations, and rainfall, among others.A regular network of 179 wells was monitored and surveyed in this study. Spatial and temporal changes in the water table and in the hydrochemistry of the aquifer were monitored between 1991 and 1998, a span which included an exceptionally rainy period (1996). Data are compared with those from 1971, the year groundwater exploitation began.The studied region is characterized by a semi-arid climate, mean annual rainfall of 391 mm (between 1977 and 1998), mean temperature of 17.8 °C, and mean rainfall input of 142 mm. In the dry season, high temperature combined with low rainfall and intensive pumping operations give rise to salinization of shallow groundwater. Groundwater in the area of study circulates in two principal hydrogeological matrices :1. Sandy-calcareous Plio-Quaternary and paleozoic strata in costal sectors and the eastern part located between Tnine Chtouka and Bir Jdid. These hydrogeological strata are characterized by significant porosity and permeability and are exploited at a shallow depth, generally less than 14 m, under sandy-clayed soil.2. A Cretaceous aquifer in marly limestone located between Oum-er-Rbia River and Tnine Chtouka. This aquifer is characterized by a low permeability and a water table generally exceeding 24 m in depth.Monitoring showed that after the heavy rains of 1996 (943 mm, with infiltration of 142 mm), the water table rose markedly in all study wells and a lagged dilution (3 to 6 months) was noted for all mineral salts dissolved in water. In fact, the water table, which had dropped between 1971 and 1995 (10 m in the costal sectors and 20 m in the others parts of the studied region), rose by an average 4.5 to 12.5 m in the central and up-gradient parts of the plain. Several factors were at work between 1971 and 1995: decreased pumping times (about 15 minutes) combined with sharp decreases in the thickness of the saturated zone; appearance of a closed piezometric level in the western region between Oum-er-Rbia River and Tnine Chtouka; and desiccation of 59 wells. With the aid of a polynomial model, annual level evolution of the five coastal test piezometers showed correlation factors of 0.76 to 0.93 respectively for years 1996 and 1997. Other quantitative effects of exceptional rains on groundwater identified include: increased pumping time (up from less than 15 minutes prior to the heavy rains of 1996); increased saturated zone thickness; rises in the water-table surpassing former sea-level heights in certain wells ; general advancement of the piezometric levels towards the coastline; and increased aquifer thickness stemming from longer pumping times.In terms of quality, groundwater showed gradually increasing salinity (by a factor of 2) between 1971 and 1995 and significant improvements after the rains of 1996. Between 1971 and 1995, increased mineralization was observed mainly in coastal and eastern parts of the aquifer between Tnine Chtouka and Bir Jdid. Conductivity of the waters in some coastal wells increased from 5 mS/cm to more than 10 mS/cm. After the exceptional rains of 1996, differences ranging from 0.5 to more than 4 mS/cm were observed in 71 % of the 179 wells analysed. Over the same period, chloride concentrations decreased by average values ranging from 150 to 500 mg/l (higher decreases surpassed 1000 mg/l). By contrast, spatial distributions of conductivity and of the main mineral salts remained unchanged and coastal and eastern groundwaters were still the most vulnerable to high salinity.The quantitative and qualitative effects of heavy rain point to the high sensitivity of these groundwaters to rain input, which is the principal recharge source of the studied aquifer

Language and power : the Saudi tertiary English language classroom

University of Technology Sydney. Faculty of Arts and Social Sciences.Many studies confirm the positive role of the student’s first language (L1) in the English language (EL) classroom. However, the English Language at the Future University (a pseudonym) in the Kingdom of Saudi Arabia (KSA) adopts an English-only approach in tertiary EL classrooms and this approach has proved to be problematic for teachers and students alike. This research, using a qualitative approach, investigates the role of L1 in EL teaching in a tertiary EL institution. Data were collected from teacher interviews, focus groups with students, and classroom observations. The purpose of the study was to contribute to research in the field of L1 use in English as a foreign language (EFL) contexts by: exposing the language ideologies underpinning the informal but effective ban on L1 in L2 classrooms; exploring the roles of L1 in the English classroom; and examining the relation between language choice and power practices in the English classroom. Analysis of the data showed that the Arabic language existed in the EFL classrooms as a visible or invisible resource and played a variety of cognitive, pedagogic, and affective roles. The participants’ perceptions towards the use of Arabic in Saudi EFL classrooms indicated that certain language ideologies included or excluded Arabic. The findings also revealed the exercise of power in the verbal and nonverbal practices of both teachers and students in these classrooms. Teachers disciplined students either through surveillance (Foucault 1977) or through their choice of language. Power is exercised differently in different contexts; in the Saudi classroom, the teacher’s role is shaped by particular cultural understandings of knowledge and authority. This study argues that the English-only approach enhances the teacher’s powerful status and marginalises students. Since “there are no relations of power without resistance” (Foucault 1980, p. 142), participating students responded to the power exercised by teachers through language choice and by resisting certain practices and classroom regimes. It was also found that the judicious utilisation of the Arabic language contributed to a more equal distribution of power in the Saudi English classroom. The students used Arabic to negotiate power with their teachers and, when they were not allowed to use Arabic, they were less engaged in and more resistant to the learning of English. Therefore, this research argues that the inclusion of the Arabic language in the Saudi EL classroom allows students to negotiate power with the teacher

A common mechanism for efficient N 2 O reduction in diverse isolates of nodule‐forming bradyrhizobia

Bradyrhizobia are abundant soil bacteria, which can form nitrogen‐fixing symbioses with leguminous plants, including important crops such as soybean, cowpea and peanut. Many bradyrhizobia can denitrify, but studies have hitherto focused on a few model organisms. We screened 39 diverse Bradyrhizobium strains, isolated from legume nodules. Half of them were unable to reduce N2O, making them sources of this greenhouse gas. Most others could denitrify NO3‐ to N2. Time‐resolved gas kinetics and transcription analyses during transition to anaerobic respiration revealed a common regulation of nirK, norCB and nosZ (encoding NO2‐, NO and N2O reductases), and differing regulation of napAB (encoding periplasmic NO3‐ reductase). A prominent feature in all N2‐producing strains was a virtually complete hampering of NO3‐ reduction in presence of N2O. In‐depth analyses suggest that this was due to a competition between electron transport pathways, strongly favouring N2O over NO3‐ reduction. In a natural context, bacteria with this feature would preferentially reduce available N2O, produced by themselves or other soil bacteria, making them powerful sinks for this greenhouse gas. One way to augment such populations in agricultural soils is to develop inoculants for legume crops with dual capabilities of efficient N2‐fixation and efficient N2O reduction

Manajemen Desain Lingkungan Pendidikan Anak Usia Dini di Pusat Tumbuh Kembang Anak Pendidikan Islam Anak Usia Dini Alauddin Makassar

Penelitian ini bertujuan untuk mengetahui gambaran penataan atau pengelolaan desain lingkungan Pendidikan Anak Usia Dini (PAUD) baik lingkungan psikis maupun fisik (indoor dan outdoor) di Pusat Tumbuh Kembang Anak (PTKA) Pendidikan Islam Anak Usia Dini (PIAUD) Alauddin Kabupaten Gowa. Jenis penelitian ini merupakan penelitian kualitatif dengan satu subjek yakni guru PTKA PIAUD Alauddin. Kabupaten Gowa. Data dikumpulkan menggunakan tehnik wawancara terstruktur yang hasilnya menggunakan deskriptif. Hasil penelitian menunjukkan bahwa PTKA PIAUD Alauddin berusaha menciptakan lingkungan psikis melalui pendekatan guru terhadap peserta didik agar anak merasa nyaman ketika berada di sekolah. Sedangkan untuk desain lingkungan fisik (indoor dan outdoor) guru selalu mengedepankan prinsip pengelolaan Lingkungan PAUD yakni: keserasian, keseimbangan, keamanan, dan kesatupaduan. Lingkungan outdoor cukup luas untuk anak bereksplorasi, terdapat beberapa alat permainan edukatif yang dapat mengembangkan berbagai aspek perkembangan anak seperti perosotan, tempat climbing, rumah-rumahan serta terowongan. Lingkungan indoor terdiri dari beberapa ruangan yaitu ruangan belajar, ruangan tidur dan toilet

A Delayed Black and Scholes Formula I

In this article we develop an explicit formula for pricing European options when the underlying stock price follows a non-linear stochastic differential delay equation (sdde). We believe that the proposed model is sufficiently flexible to fit real market data, and is yet simple enough to allow for a closed-form representation of the option price. Furthermore, the model maintains the no-arbitrage property and the completeness of the market. The derivation of the option-pricing formula is based on an equivalent martingale measure

Gaze prediction using machine learning for dynamic stereo manipulation in games.

Comfortable, high-quality 3D stereo viewing is becoming a requirement for interactive applications today. Previous research shows that manipulating disparity can alleviate some of the discomfort caused by 3D stereo, but it is best to do this locally, around the object the user is gazing at. The main challenge is thus to develop a gaze predictor in the demanding context of real-time, heavily task-oriented applications such as games. Our key observation is that player actions are highly correlated with the present state of a game, encoded by game variables. Based on this, we train a classifier to learn these correlations using an eye-tracker which provides the ground-truth object being looked at. The classifier is used at runtime to predict object category - and thus gaze - during game play, based on the current state of game variables. We use this prediction to propose a dynamic disparity manipulation method, which provides rich and comfortable depth. We evaluate the quality of our gaze predictor numerically and experimentally, showing that it predicts gaze more accurately than previous approaches. A subjective rating study demonstrates that our localized disparity manipulation is preferred over previous methods