160 research outputs found
Saltwater Intrusion Appraisal of Shallow Aquifer in Burutu Area of the Western Niger Delta with 2D Electrical Resistivity Tomography
The area is faced with endemic groundwater quality problems arising from abandoned shallow and deep boreholes. The abandonment of shallow boreholes is presumed to have been caused by saltwater intrusion from the ocean. The objective of this paper is to examine if saltwater is responsible for groundwater degradation associated with shallow groundwater aquifer. To achieve this, a multi-electrodes ABEM SAS 4000 Terrameter was used in the acquisition of 2D electrical resistivity tomography data. Inverse models which estimate actual subsurface geologic resistivity was generated from RES2DINV software and subsequently geologic information were construed from them. The interpretation of the various profiles returned resistivity values which contrasted the existence of saltwater in the pore spaces of groundwater aquifer media in the area under investigation. Resistivity images of values ranged from 2.34Ωm to 70 Ωm where interpreted as clays, greater than 70-90Ωm as fine sand and 90Ωm and above where interpret as medium sand. The evidence revealed by the 2D electrical resistivity tomography investigation combined with geochemistry of groundwater from literature suggested that abandonment of shallow boreholes are probably not related to saltwater intrusion. The study has established that poor groundwater quality being experienced is not caused by saltwater intrusion rather by iron which cannot be separately distinguished from groundwater by resistivity technique. Key Word: 2D electrical resistivity tomography, Burutu, Saltwater intrusion, shallow aquifer, western Niger Delta, groundwater qualit
Varhaiskasvatusta metsÀssÀ:ympÀristö ja leikki sosiaalisia taitoja vahvistamassa
TiivistelmĂ€. TĂ€ssĂ€ kandidaatintutkielmassa tutkimme, miten luonto- ja metsĂ€pĂ€ivĂ€kotien toimintatavat tukevat 3â6-vuotiaiden lasten sosiaalisia taitoja. Luonto- ja metsĂ€pĂ€ivĂ€kodeissa luonto on sekĂ€ varhaiskasvatuksen toimintaympĂ€ristö ettĂ€ pedagoginen vĂ€line oppimisessa. Erilaisten tutkimusten kautta tutustuimme nĂ€iden pĂ€ivĂ€kotien kĂ€ytĂ€ntöihin ja toimintatapoihin, kuten pĂ€ivĂ€jĂ€rjestyksiin, asenteisiin ja opettajan positioon suhteessa lapsiin. Taustateorioiden ja kĂ€sitteiden avulla tutkimme, miten luonto- ja metsĂ€pĂ€ivĂ€kotien ominaiset piirteet ja kĂ€ytĂ€nteet tukevat lasten sosiaalisia taitoja.
Teoreettisena viitekehyksenÀ tutkielmassamme on kolme taustateoriaa: Bronfenbrennerin ekologinen teoria, kontekstuaalisen kasvun malli ja prosessuaalinen ja relationaalinen nÀkemys lasten ja ympÀristön suhteesta. NÀissÀ kaikissa teorioissa lapsi nÀhdÀÀn erottamattomana osana ympÀristöÀ, mikÀ on keskeinen nÀkökulma tutkielmamme kannalta. Toteutimme tutkielman integroivana, kuvailevana kirjallisuuskatsauksena.
Tutkimustulokset jakautuivat kahteen teemaan: ympÀristöön ja leikkiin. SekÀ psykososiaalinen ettÀ fyysinen ympÀristö tarjoumineen ovat sosiaalisten taitojen kannalta tÀrkeÀssÀ roolissa. Varhaiskasvatuskontekstissa syntyvÀÀ stressiÀ vÀhentÀÀ luonto itsessÀÀn, pienemmÀt ryhmÀkoot ja vÀhÀinen melu. Lapsiin kohdistuva luottamus antaa mahdollisuuksia sosiaalisten taitojen kehittÀmiseen vastuun ja vapauden kautta. Leikin osalta tuloksista nousivat esille kuvitteluleikki ja riskialtis leikki. NÀissÀ leikeissÀ lapset saavat spontaaneja sosiaalisia kontakteja ja ovat toistensa kanssa aktiivisessa vuorovaikutuksessa
Avaliação da variabilidade genética de Eragrostis plana Nees (Poaceae - Chloridoideae) no Rio Grande do Sul através de ISSR.
CNBOT
A preliminary approach to the phylogeny of the genus Paspalum (Poaceae).
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Avaliação da variabilidade genética de Eragrostis plana Nees (capim-annoni-2) em populaçÔes do Estado do Rio Grande do Sul - resultados parciais.
Eragrostis plana Nees Ă© um gĂȘnero africano de gramĂnea, o qual apresenta graves problemas por comportar-se uma planta invasora, de fĂĄcil disseminação, alĂ©m de ser uma gramĂnea que demostra competição com as espĂ©cies campestres nativas, contribuindo com a perda da biodiversidade do Bioma Pampa. O presente estudo tem por objetivo compreender a estrutura genĂ©tica e determinar sua variabilidade intra e inter-populacional.Zootec
Probe-level estimation improves the detection of differential splicing in Affymetrix exon array studies
Neural processing associated with cognitive and affective Theory of Mind in adolescents and adults
Theory of Mind (ToM) is the ability to attribute thoughts, intentions and beliefs to others. This involves component processes, including cognitive perspective taking (cognitive ToM) and understanding emotions (affective ToM). This study assessed the distinction and overlap of neural processes involved in these respective components, and also investigated their development between adolescence and adulthood. While data suggest that ToM develops between adolescence and adulthood, these populations have not been compared on cognitive and affective ToM domains. Using fMRI with 15 adolescent (aged 11â16 years) and 15 adult (aged 24â40 years) males, we assessed neural responses during cartoon vignettes requiring cognitive ToM, affective ToM or physical causality comprehension (control). An additional aim was to explore relationships between fMRI data and self-reported empathy. Both cognitive and affective ToM conditions were associated with neural responses in the classic ToM network across both groups, although only affective ToM recruited medial/ventromedial PFC (mPFC/vmPFC). Adolescents add- itionally activated vmPFC more than did adults during affective ToM. The specificity of the mPFC/vmPFC response during affective ToM supports evidence from lesion studies suggesting that vmPFC may integrate affective information during ToM. Furthermore, the differential neural response in vmPFC between adult and adolescent groups indicates developmental changes in affective ToM processing
Reduced prosocial motivation and effort in adolescents with conduct problems and callousâunemotional traits
Background: Prosocial behaviours â acts that benefit others â are of crucial importance for many species including humans. However, adolescents with conduct problems (CP), unlike their typically developing (TD) peers, demonstrate markedly reduced engagement in prosocial behaviours. This pattern is particularly pronounced in adolescents with CP and high levels of callousâunemotional traits (CP/HCU) who are at increased risk of developing psychopathy in adulthood. While a substantial amount of research has investigated the cognitiveâaffective mechanisms thought to underlie antisocial behaviour, much less is known about the mechanisms that could explain reduced prosocial behaviours in adolescents with CP. Methods: Here we examined the willingness to exert effort to benefit oneself (self) and another person (other, prosocial condition) in children with CP/HCU, CP and lower levels of CU traits (CP/LCU) and their TD peers. The task captured both prosocial choices, and actual effort exerted following prosocial choices, in adolescent boys aged 11â16 (27 CP/HCU; 34 CP/LCU; 33 TD). We used computational modelling to reveal the mechanistic processes involved when choosing prosocial acts. Results: We found that both CP/HCU and CP/LCU groups were more averse to initiating effortful prosocial acts than TD adolescents â both at a cognitive and at a behavioural level. Strikingly, even if they chose to initiate a prosocial act, the CP/HCU group exerted less effort following this prosocial choice than other groups. Conclusions: Our findings indicate that reduced exertion of effort to benefit others may be an important factor that differentiates adolescents with CP/HCU from their peers with CP/LCU. They offer new insights into what might drive low prosocial behaviour in adolescents with CP, including vulnerabilities that may particularly characterise those with high levels of CU traits
Modulation of amygdala response to task-irrelevant emotion
It has been shown that as cognitive demands of a non-emotional task increase, amygdala response to task-irrelevant emotional stimuli is reduced. However, it remains unclear whether effects are due to altered task demands, or altered perceptual input associated with task demands. Here, we present fMRI data from 20 adult males during a novel cognitive conflict task in which the requirement to scan emotional information was necessary for task performance and held constant across levels of cognitive conflict. Response to fearful facial expressions was attenuated under high (vs low) conflict conditions, as indexed by both slower reaction times and reduced right amygdala response. Psychophysiological interaction analysis showed that increased amygdala response to fear in the low conflict condition was accompanied by increased functional coupling with middle frontal gyrus, a prefrontal region previously associated with emotion regulation during cognitive task performance. These data suggest that amygdala response to emotion is modulated as a function of task demands, even when perceptual inputs are closely matched across load conditions. PPI data also show that, in particular emotional contexts, increased functional coupling of amygdala with prefrontal cortex can paradoxically occur when executive demands are lower
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