Neural Mechanisms of Young Adult Sexual Decision-Making and Risk Behavior

Sexual risk behavior among young adults is a serious public health concern; 50% will contract a sexually transmitted infection (STI) before the age of 25. The current study collected self-report personality and sexual history data, as well as neuroimaging, experimental behavioral (e.g., real-time hypothetical sexual decision making data), and self-report sexual arousal data from 120 heterosexual young adults ages 18-26. In addition, longitudinal changes in self-reported sexual behavior were collected from a subset (n = 70) of the participants. The primary aims of the study were (1) to predict differences in self-report sexual behavior and hypothetical sexual decision-making (in response to sexually explicit audio-visual cues) as a function of ventral striatum (VS) and amygdala activity, (2) test whether the association between sexual behavior/decision-making and brain function is moderated by gender, self-reported sexual arousal, and/or trait-level personality factors (i.e., self-control, impulsivity, and sensation seeking) and (3) to examine how the main effects of neural function and interaction effects predict sexual risk behavior over time. Our hypotheses were mostly supported across the sexual behavior and decision-making outcome variables, such that neural risk phenotypes (heightened reward-related ventral striatum activity coupled with decreased threat-related amygdala activity) were associated with greater lifetime sexual partners at baseline measured and over time (longitudinal analyses). Impulsivity moderated the relationship between neural function and self-reported number of sexual partners at baseline and follow up measures, as well as experimental condom use decision-making. Sexual arousal and sensation seeking moderated the relationship between neural function and baseline and follow up self-reports of number of sexual partners. Finally, unique gender differences were observed in the relationship between threat and reward-related neural reactivity and self-reported sexual risk behavior. The results of this study provide initial evidence for the potential role for neurobiological approaches to understanding sexual decision-making and risk behavior. With continued research, establishing biomarkers for sexual risk behavior could help inform the development of novel and more effective individually tailored sexual health prevention and intervention efforts.

Boron isotope and B/Ca ratios of planktonic foraminifera

Here a new analytical methodology is described for measuring the isotopic composition of boron in foraminifera using multicollector inductively coupled plasma mass spectrometry (MC-ICPMS). This new approach is fast (~10 samples analysed in duplicate per analytical session) and accurate (to better than 0.25 per mil at 95% confidence) with acceptable sample size requirements (1-3 mg of carbonate). A core top calibration of several common planktic and two benthic species from geographically widespread localities shows a very close agreement between the isotopic composition measured by MC-ICPMS and the isotopic composition of B(OH)-4 in seawater (as predicted using the recently measured isotopic equilibrium factor of 1.0272) at the depth of habitat. A down core and core top investigation of boron concentration (B/Ca ratio) shows that the partition coefficient is influenced by [CO2-3] complicating the application of this proxy. Nevertheless, it is demonstrated that these two proxies can be used to fully constrain the carbonate system of surface water in the Caribbean Sea (ODP Site 999A) over the last 130 kyr. This reconstruction shows that during much of the Holocene and the last interglacial period surface water at Site 999A was in equilibrium with the atmosphere with respect to CO2. During the intervening colder periods although the surface water pCO2 was lower than the Holocene, it was a minor to significant source of CO2 to the atmosphere possibly due to either an expansion of the eastern equatorial Atlantic upwelling zone, or a more local expansion of coastal upwelling in the southern Caribbean. Such reorganisation of the oceanic carbonate system in favour of a larger source of CO2 to the atmosphere from the equatorial ocean may require mechanisms responsible for lowering atmospheric CO2 during glacial periods to be more efficient than previously supposed.

Immersive Learning Research Network

Computer games have now been around for over three decades and the term serious games has been attributed to the use of computer games that are thought to have educational value. Game-based learning (GBL) has been applied in a number of different fields such as medicine, languages and software engineering. Furthermore, serious games can be a very effective as an instructional tool and can assist learning by providing an alternative way of presenting instructions and content on a supplementary level, and can promote student motivation and interest in subject matter resulting in enhanced learning effectiveness. REVLAW (Real and Virtual Reality Law) is a research project that the departments of Law and Computer Science of Westminster University have proposed as a new framework in which law students can explore a real case scenario using Virtual Reality (VR) technology to discover important pieces of evidence from a real-given scenario and make up their mind over the crime case if this is a murder or not. REVLAW integrates the immersion into VR as the perception of being physically present in a non-physical world. The paper presents the prototype framework and the mechanics used to make students focus on the crime case and make the best use of this immersive learning approach.

High resolution Thomson Parabola Spectrometer for full spectral capture of multi-species ion beams

We report on the experimental characterisation of laser-driven ion beams using a Thomson Parabola Spectrometer (TPS) equipped with trapezoidally shaped electric plates, proposed by Gwynne et al. [Rev. Sci. Instrum. 85, 033304 (2014)]. While a pair of extended (30 cm long) electric plates was able to produce a significant increase in the separation between neighbouring ion species at high energies, deploying a trapezoidal design circumvented the spectral clipping at the low energy end of the ion spectra. The shape of the electric plate was chosen carefully considering, for the given spectrometer configuration, the range of detectable ion energies and species. Analytical tracing of the ion parabolas matches closely with the experimental data, which suggests a minimal effect of fringe fields on the escaping ions close to the wedged edge of the electrode. The analytical formulae were derived considering the relativistic correction required for the high energy ions to be characterised using such spectrometer.

The effects of transients on photospheric and chromospheric power distributions

We have observed a quiet Sun region with the Swedish 1-meter Solar Telescope (SST) equipped with CRISP Imaging SpectroPolarimeter. High-resolution, high-cadence, H-alpha line scanning images were taken to observe different layers of the solar atmosphere from the photosphere to upper chromosphere. We study the distribution of power in different period-bands at different heights. Power maps of the upper photosphere and the lower chromosphere show suppressed power surrounding the magnetic-network elements, known as "magnetic shadows". These also show enhanced power close to the photosphere, traditionally referred to as"power halos". The interaction between acoustic waves and inclined magnetic fields is generally believed to be responsible for these two effects. In this study we explore if small-scale transients can influence the distribution of power at different heights. We show that the presence of transients, like mottles, Rapid Blueshifted Excursions (RBEs) and Rapid Redshifted Excursions (RREs), can strongly influence the power-maps. The short and finite lifetime of these events strongly affects all powermaps, potentially influencing the observed power distribution. We show that Doppler-shifted transients like RBEs and RREs that occur ubiquitously, can have a dominant effect on the formation ofthe power halos in the quiet Sun. For magnetic shadows, transients like mottles do not seem to have a significant effect in the power suppression around 3 minutes and wave interaction may play a key role here. Our high cadence observations reveal that flows, waves and shocks manifest in presence of magnetic fields to form a non-linear magnetohydrodynamic system.

Assessing trends in land use change in the Borana rangeland Ethiopia as one cause of greenhouse gas emissions and carbon sequestration variations

Landnutzungsänderungen sind eine wesentliche Ursache von Treibhausgasemissionen. Die Umwandlung von Ökosystemen mit permanenter natürlicher Vegetation hin zu Ackerbau mit zeitweise vegetationslosem Boden (z.B. nach der Bodenbearbeitung vor der Aussaat) führt häufig zu gesteigerten Treibhausgasemissionen und verminderter Kohlenstoffbindung. Weltweit dehnt sich Ackerbau sowohl in kleinbäuerlichen als auch in agro-industriellen Systemen aus, häufig in benachbarte semiaride bis subhumide Rangeland Ökosysteme. Die vorliegende Arbeit untersucht Trends der Landnutzungsänderung im Borana Rangeland Südäthiopiens. Bevölkerungswachstum, Landprivatisierung und damit einhergehende Einzäunung, veränderte Landnutzungspolitik und zunehmende Klimavariabilität führen zu raschen Veränderungen der traditionell auf Tierhaltung basierten, pastoralen Systeme. Mittels einer Literaturanalyse von Fallstudien in ostafrikanischen Rangelands wurde im Rahmen dieser Studie ein schematisches Modell der Zusammenhänge von Landnutzung, Treibhausgasemissionen und Kohlenstofffixierung entwickelt. Anhand von Satellitendaten und Daten aus Haushaltsbefragungen wurden Art und Umfang von Landnutzungsänderungen und Vegetationsveränderungen an fünf Untersuchungsstandorten (Darito/Yabelo Distrikt, Soda, Samaro, Haralo, Did Mega/alle Dire Distrikt) zwischen 1985 und 2011 analysiert. In Darito dehnte sich die Ackerbaufläche um 12% aus, überwiegend auf Kosten von Buschland. An den übrigen Standorten blieb die Ackerbaufläche relativ konstant, jedoch nahm Graslandvegetation um zwischen 16 und 28% zu, während Buschland um zwischen 23 und 31% abnahm. Lediglich am Standort Haralo nahm auch „bare land“, vegetationslose Flächen, um 13% zu. Faktoren, die zur Ausdehnung des Ackerbaus führen, wurden am Standort Darito detaillierter untersucht. GPS Daten und anbaugeschichtlichen Daten von 108 Feldern auf 54 Betrieben wurden in einem Geographischen Informationssystem (GIS) mit thematischen Boden-, Niederschlags-, und Hangneigungskarten sowie einem Digitales Höhenmodell überlagert. Multiple lineare Regression ermittelte Hangneigung und geographische Höhe als signifikante Erklärungsvariablen für die Ausdehnung von Ackerbau in niedrigere Lagen. Bodenart, Entfernung zum saisonalen Flusslauf und Niederschlag waren hingegen nicht signifikant. Das niedrige Bestimmtheitsmaß (R²=0,154) weist darauf hin, dass es weitere, hier nicht erfasste Erklärungsvariablen für die Richtung der räumlichen Ausweitung von Ackerland gibt. Streudiagramme zu Ackergröße und Anbaujahren in Relation zu geographischer Höhe zeigen seit dem Jahr 2000 eine Ausdehnung des Ackerbaus in Lagen unter 1620 müNN und eine Zunahme der Schlaggröße (>3ha). Die Analyse der phänologischen Entwicklung von Feldfrüchten im Jahresverlauf in Kombination mit Niederschlagsdaten und normalized difference vegetation index (NDVI) Zeitreihendaten dienten dazu, Zeitpunkte besonders hoher (Begrünung vor der Ernte) oder niedriger (nach der Bodenbearbeitung) Pflanzenbiomasse auf Ackerland zu identifizieren, um Ackerland und seine Ausdehnung von anderen Vegetationsformen fernerkundlich unterscheiden zu können. Anhand der NDVI Spektralprofile konnte Ackerland gut Wald, jedoch weniger gut von Gras- und Buschland unterschieden werden. Die geringe Auflösung (250m) der Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI Daten führte zu einem Mixed Pixel Effect, d.h. die Fläche eines Pixels beinhaltete häufig verschiedene Vegetationsformen in unterschiedlichen Anteilen, was deren Unterscheidung beeinträchtigte. Für die Entwicklung eines Echtzeit Monitoring Systems für die Ausdehnung des Ackerbaus wären höher auflösende NDVI Daten (z.B. Multispektralband, Hyperion EO-1 Sensor) notwendig, um kleinräumig eine bessere Differenzierung von Ackerland und natürlicher Rangeland-Vegetation zu erhalten. Die Entwicklung und der Einsatz solcher Methoden als Entscheidungshilfen für Land- und Ressourcennutzungsplanung könnte dazu beitragen, Produktions- und Entwicklungsziele der Borana Landnutzer mit nationalen Anstrengungen zur Eindämmung des Klimawandels durch Steigerung der Kohlenstofffixierung in Rangelands in Einklang zu bringen.

Famílias Unipessoais Idosas: um estudo das redes sociais pessoais de idosos que vivem sós

Objetivos: O presente estudo tem como objetivo analisar as características estruturais, funcionais e relacionais-contextuais das redes sociais pessoais de famílias unipessoais idosas. Metodologia: Utilizámos para recolha de dados um questionário para caracterizar sociodemograficamente a amostra, o Instrumento de Análise da Rede Social Pessoal (versão para idosos) (IARSP-Idosos) (Guadalupe, 2010; Guadalupe e Vicente 2012) e a escala de solidão UCLA (Neto, 1989). Participantes: A amostra é constituída por 567 indivíduos com média de idades de 75,53 anos, maioritariamente do sexo feminino (63,0%; n = 357). Predominam os sujeitos casados (53,7%; n = 304), com filhos (87,8%; n = 498) e em situação de coabitação (n = 450; 79,4%). Contudo, 20,6% (n = 117) vivem sós, constituindo as famílias unipessoais. Resultados: As redes sociais dos idosos têm em média 7,99 elementos, predominantemente familiares (M = 76,89%). Os participantes percecionam um nível elevado de apoio por parte das suas redes. São redes coesas, pouco dispersas e os contactos entre os elementos são frequentes. As mulheres, os indivíduos solteiros, viúvos ou divorciados e os idosos sem filhos têm uma maior probabilidade de viverem sós (p < 0,05) e estes apresentam uma maior probabilidade de necessitar de apoio social formal (p < 0,05). As famílias unipessoais, quando comparadas com os que não vivem sós, apresentam um maior número de campos relacionais e maior proporção de relações de amizade e de vizinhança (p < 0,05). Têm menor perceção de apoio material e instrumental, informativo, companhia social, acesso a novos vínculos e reciprocidade de apoio (p < 0,05). Além disso, referem menor frequência de contactos e uma maior dispersão geográfica (p < 0,05). Nas famílias unipessoais, observou-se a existência de correlações negativas significativas (p < 0,05) entre a percepção de solidão e o tamanho da rede, a proporção das relações familiares na rede, o apoio emocional e informativo e a reciprocidade de apoio. CONCLUSÃO: Os idosos com famílias unipessoais percecionam menor apoio por parte das suas redes, tendo uma maior propensão à solidão. É fundamental, ao longo do ciclo vital, promover a quantidade e qualidade dos vínculos, no sentido de manter a efetividade do suporte das redes mesmo quando se vive só. / Objectives: The present study aims to analyze the structural, functional and relational-contextual characteristics of older single-person households. Methodology: We used as instruments a questionnaire to evaluate sociodemographic data, the Instrumento de Análise da Rede Social Pessoal (version for elderly people: IARSP-Idosos) (Guadalupe, 2010; Guadalupe e Vicente 2012) and the UCLA Loneliness Scale (Neto, 1989). Participants: The sample consists of 567 individuals with an average age of 75.53 years, mostly females (63.0%; n = 357). There is a predominance of married individuals (53.7%; n = 304) with children (87.8%; n = 498). Older people live mainly in cohabitation (n = 450; 79.4%), however 20.6% oh them live alone, constituting one-person households. Results: The elderly personal social networks have 8 elements, on average, with a predominance of family relationships (M = 76.89%). The participants perceived a high level of support from their networks. In general the networks are cohesive, with low dispersion and have frequent contacts. The women, single, widowed or divorced and childless elderly are more likely to live alone (p < 0.05) and to need social services support (p < 0.05). The single-person households, compared with those who do not live alone, have a greater number of relational fields and a higher proportion of friendships and neighborhood relations (p < 0.05). They have a lower perception of material and informative support, social company and acess to new ties and reciprocal support (p < 0.05). They also refer lowest frequency of contacts and a wider geographical dispersion (p < 0.05). In single-person households there was a negative significant correlation between the perception of loneliness and the social network size, the proportion of family relationships in the network, emotional and informational support and reciprocal support. Conclusions: The elderly single-person households perceived less support from their networks and a greater propensity to loneliness. It is critical to promot the quality of ties, rather then their quantity, throughout the life cycle, in order to maintain the network effectiveness even when the person lives alone.

Impacts of oil exploration and exploitation activities on marine environment

Iran possess huge oil reservoir and occupies second place in OPEC. Recent investigation has revealed that reservoir capacity in the country amount to 60 billion barrel of oil. Many measures has been carried out to increase production capacity of oil fields to 4.2 million barrel per day. Thus any distribution in oil exploration may leave adverse effects on social and economic activities. Unfortunately due to absence of a comprehensive CPM on environmental impact assessment, lots of environmental distribution has been occurred in land and off-shore. It is well known that implementation of EIA can reduce environmental hazards. In the present investigation, all major and minor activities associated with oil exploration is identified and subsequently their effects on physical, chemical and biological environment (aquatic) has been brought out. In this context, economical, social and cultural effects of marine oil exploration is also discussed. Subsequently, all methods of EIA were studied and best mitigation plans were drawn up both for exploitation and exploration phases.

A review on systematic and taxonomic of the Persian Gulf fish species, based on geographical distribution pattern and habitat diversity, using by GIS

During the period from 2011 - 2015 with the aim of this study was to systematically review and in particular the revised classification of the Persian Gulf (and the Strait of Hormuz) and to obtain new information about the final confirmed list of fish species of Iranian waters of the Persian Gulf (and Hormuz Strait), samples of museums, surveys and sampling, and comparative study of all available sources and documentation was done. Classification systematic of sharks and batoids and bony fishes. Based on the results, the final list of approved fish of the Persian Gulf (including the Strait of Hormuz and Gulf of Oman border region) are 907 species in 157 families, of which 93 species of fish with 28 cartilaginous families (including 18 families with 60 species and 10 families with 34 species of shark and batoids); and 129 families with 814 species of bony fishes are. The presence of 11 new family with only one representative species in the area include Veliferidae, Zeidae, Sebastidae, Stomiidae, Dalatiidae, Zanclidae, Pempheridae, Lophiidae Kuhliidae, Etmoptridae and Chlorophthalmidae also recently introduced and approved. The two families based Creediidae Clinidae and their larvae samples for newly identified area. 62 families with mono-species and 25 families with more than 10 species are present including Gobiidae (53), Carangide (48), Labride (41), Blenniidae (34), Apogonidae (32) and Lutjanidae (31) of bony fishes, Carcharhinidae (26) of sharks and Dasyatidae (12) in terms of number of species of batoids most families to have their data partitioning. Also, 13 species as well as endemic species introduced the Persian Gulf and have been approved in terms of geographical expansion of the Persian Gulf are unique to the area.Two species of the family Poeciliidae and Cyprinodontidae have species of fresh water to the brackish coastal habitats have found a way;in addition to 11 types of families Carcharhinidae, Clupeidae, Chanidae, Gobidae, Mugilidae, Sparidae also as a species, with a focus on freshwater river basins in the south of the country have been found. In this study, it was found that out of 907 species have been reported from the study area, 294 species (32.4 %) to benthic habitats (Benthic habitats) and 613 species (67.6 %) in pelagic habitats (Pelagic habitats) belong. Coral reefs and rocky habitats in the range of benthic fish (129 species - 14.3 %) and reef associated fishes in the range of pelagic fishes (432 species – 47.8 %), the highest number and percentage of habitat diversity (Species habitats) have been allocated. As well as fish habitats with sea grass and algae beds in benthic habitat (17 species- 1.9 %) and pelagic - Oceanic (Open sea) in the whole pelagic fish (30 species – 3.3 %), the lowest number and percentage of habitat diversity into account. From the perspective of animal geography (Zoogeography) and habitat overlaps and similarities (Habitat overlapping) fish fauna of the Persian Gulf compared with other similar seas (tropical and subtropical, and warm temperate) in the Indian Ocean area - calm on the surface, based on the presence of certain species that the fish fauna of the Persian Gulf to the Red Sea and the Bay of Bengal (East Arabian Sea) compared to other regions in the Indian Ocean (Pacific) is closer (about 50%), and the Mediterranean (East area) and The Hawaiian Islands have the lowest overlap and similarity of habitat and species (about 10%).

Nutritional profile and yield of oyster mushroom cultivated on selected agricultural wastes

Research on mushroom production and products is gaining more grounds globally and in particular Nigeria. This study was carried out to determine nutritional relationship between the substrate used for cultivation and the fruiting body on each of the substrates. Agro-wastes, namely: palm ( Elaeis guineensis ) fruit shaft, plantain ( Musa paradisiaca ) leaves, sawdust and kenaf ( Hibiscus cannabinus ) stem, were assessed for suitability as substrates for cultivation of oyster mushroom ( Pleurotus floridanus Singer ). The spawn of the mushroom was used to inoculate each of the substrates, using a complete randomised design, with five replicates for each substrate. Results showed that all the substrates supported mycelia growth and development of fruiting bodies of the fungus. There were significant differences (P<0.05) among substrates in terms of number of days to complete mycelia run, with the least recorded in palm fruit shaft (25.20), and the highest in kenaf (32.40). Total yield also differed significantly (P<0.05), with the highest in palm fruit shaft (51.4 g 100 g-1) and lowest in plantain leaves (6.0 g 100 g-1). There was also significant difference (P<0.05) in the nutritional content of fruiting bodies, the highest fat content being on plantain leaves (1.72 g 100 g-1) and the lowest on palm fruit shaft (0.55 g 100 g-1). The trend was similar for mushroom substrates, plantain leaves having (2.55 g 100 g-1) and palm fruit shaft, (0.41g 100 g-1). Starch content for fruiting bodies was highest on sawdust (5.31 g 100 g-1) and lowest on kenaf (2.66 g 100 g-1), while for mushroom substrates, kenaf was (0.33g 100 g-1) and palm fruit shaft was (4.45g 100 g-1). There was a positive correlation (r = 0.24) between the nutrient of fruiting bodies and that of the substrate on which it was cultivated.

Using ICT Energy consumption for monitoring ICT architecture

Energy efficient policies are being applied to network protocols, devices and classical network management systems. Researchers have already studied in depth each of those fields, including for instance a long monitoring processes of various number of individual ICT equipment from where power models are constructed. With the development of smart meters and emerging protocols such as SNMP and NETCONF, currently there is an open field to couple the power models, translated to the expected behavior, with the realtime energy measurements. The goal is to derive a comparison on the power data between both of the processes in the direction of detection for possible deviations on the expected results. The logical assumption is that a fault in the usage of a particular device will not only increase its own energy usage, but also may cause additional consumption on the other devices part of the network. A platform is developed to monitor and analyze the retrieved power data of a simulated enterprise ICT infrastructure. Moreover, smart algorithms are developed which are aware of the different states that are occurring on each device during their typical use phase, as well as to detect and isolate possible anomalies. The produced results are obtained and validated with the use of Cisco switches and routers, Dell Precision stations and Raritan PDU as part of the monitored infrastructure.

Selecting candidate predictor variables for the modelling of post-discharge mortality from sepsis: a protocol development project.

Background: Post-discharge mortality is a frequent but poorly recognized contributor to child mortality in resource limited countries. The identification of children at high risk for post-discharge mortality is a critically important first step in addressing this problem. Objectives: The objective of this project was to determine the variables most likely to be associated with post-discharge mortality which are to be included in a prediction modelling study. Methods: A two-round modified Delphi process was completed for the review of a priori selected variables and selection of new variables. Variables were evaluated on relevance according to (1) prediction (2) availability (3) cost and (4) time required for measurement. Participants included experts in a variety of relevant fields. Results: During the first round of the modified Delphi process, 23 experts evaluated 17 variables. Forty further variables were suggested and were reviewed during the second round by 12 experts. During the second round 16 additional variables were evaluated. Thirty unique variables were compiled for use in the prediction modelling study. Conclusion: A systematic approach was utilized to generate an optimal list of candidate predictor variables for the incorporation into a study on prediction of pediatric post-discharge mortality in a resource poor setting.

How ecotourism works at the community-level : the case of whale-watching in the Azores

Whale-watching is one of the fastest growing tourism industries worldwide, often viewed as a sustainable, non-consumptive strategy for the benefits of cetacean conservation and the coastal communities, alternative to and incompatible with whaling. Yet, there is paucity of research on how things actually work out at the community-level. Drawing on the research literature and my own ethnographic fieldwork, this article bridges a knowledge gap in this field while examining an Azorean context where tourism has brought a re-commodification of the whale for the community (observing wildlife as opposed to harpooning it) in the last 20 years. The analysis is focused on four main community-level implications: governance of common maritime resources, and tourism's contribution to economic sustainability, cultural identity and social relations. It is shown that whale-watching, as any other form of community-based ecotourism, is not a panacea that always promotes biodiversity conservation and economic and sociocultural sustainability for the host communities. Moreover, expanding on the theorisation of emerging institutional fields by Lawrence and Phillips, the political, historical, economic and sociocultural context of the community involved is a key factor for understanding local agency and the local specific features of new fields.

The right hippocampus leads the bilateral integration of gamma-parsed lateralized information

It is unclear whether the two hippocampal lobes convey similar or different activities and how they cooperate. Spatial discrimination of electric fields in anesthetized rats allowed us to compare the pathway-specific field potentials corresponding to the gamma-paced CA3 output (CA1 Schaffer potentials) and CA3 somatic inhibition within and between sides. Bilateral excitatory Schaffer gamma waves are generally larger and lead from the right hemisphere with only moderate covariation of amplitude, and drive CA1 pyramidal units more strongly than unilateral waves. CA3 waves lock to the ipsilateral Schaffer potentials, although bilateral coherence was weak. Notably, Schaffer activity may run laterally, as seen after the disruption of the connecting pathways. Thus, asymmetric operations promote the entrainment of CA3-autonomous gamma oscillators bilaterally, synchronizing lateralized gamma strings to converge optimally on CA1 targets. The findings support the view that interhippocampal connections integrate different aspects of information that flow through the left and right lobes.

Effect of different methods of soil preparation on soil moisture loss, weed growth and soil resistance to penetration.

The effect of different methods of soil preparation on soil moisture loss, weed growth and soil resistance to penetration has been quantified for the Latosols of Bebedouro experiment station of CPATSA-EMBRAPA, Petrolina,PE, Brazil. The methods studied are manual preparation, preparation by animal drawn wheeled tool carrier and tractorized implements. The drying characteristics of three fields with different soil physical properties were studied prior to conducting the experiment. The different methods of soil preparation caused the soil moisture loss differently. The plot prepared by animal drawn tool carrier retained more moisture for longer time even at deeper layers. The soil resistance to penetration on the surface increased with time with little variation at deeper layers.