65 research outputs found

    Field evidence of a natural capillary barrier in a gravel alluvial aquifer

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    Ozark streams commonly feature “composite” floodplains, in which the vadose zone consists of silt or silt loam soils (?1 m thick) overlying gravel subsoil. Previous work has shown that preferential flow paths can exist within the gravel subsoil, which can conduct water and P at rates exceeding the sorption capacity of the gravel. At a site on Barren Fork Creek, a 1- by 1-m infiltration plot was constructed and an infiltration experiment was performed using sequentially introduced solutes including P (the constituent of regulatory interest), Rhodamine-WT (Rh-WT, a visual tracer), and Cl− (an electrical tracer). The solute transport was measured with monitoring wells (MWs) placed 1 m from the plot boundary and 5 m down the groundwater flow gradient using an electrical resistivity imaging (ERI) array. The ERI method utilized differences between a pre-infiltration background image and subsequent temporal images taken during the test to quantify changes induced by the tracers. The infiltration test maintained a steady-state flow rate of 4.5 L min−1 for 84.75 h. Electrical resistivity imaging data showed significant changes in resistivity induced by the tracers within the soil vadose zone under the plot but no similar changes within the gravel, indicating that the interface was acting as a capillary barrier. Electrical resistivity images 5 m away from the plot showed tracer breakthrough into the gravel in areas not sampled by the MWs. Solute detection was limited in MWs, indicating that MWs could not adequately monitor movement below the capillary barrier because it controlled migration of solute to the heterogeneous phreatic zone

    A Randomized Comparison of Aripiprazole and Risperidone for the Acute Treatment of First-Episode Schizophrenia and Related Disorders: 3-Month Outcomes

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    Research findings are particularly important for medication choice for first-episode patients as individual prior medication response to guide treatment decisions is unavailable. We describe the first large-scale double-masked randomized comparison with first-episode patients of aripiprazole and risperidone, 2 commonly used first-episode treatment agents. One hundred ninety-eight participants aged 15-40 years with schizophrenia, schizophreniform disorder, schizoaffective disorder or psychotic disorder Not Otherwise Specified, and who had been treated in their lifetime with antipsychotics for 2 weeks or less were randomly assigned to double-masked aripiprazole (5-30mg/d) or risperidone (1-6mg/d) and followed for 12 weeks. Positive symptom response rates did not differ (62.8% vs 56.8%) nor did time to response. Aripiprazole-treated participants had better negative symptom outcomes but experienced more akathisia. Body mass index change did not differ between treatments but advantages were found for aripiprazole treatment for total and low-density lipoprotein cholesterol, fasting glucose, and prolactin levels. Post hoc analyses suggested advantages for aripiprazole on depressed mood. Overall, if the potential for akathisia is a concern, low-dose risperidone as used in this trial maybe a preferred choice over aripiprazole. Otherwise, aripiprazole would be the preferred choice over risperidone in most situations based upon metabolic outcome advantages and some symptom advantages within the context of similar positive symptom response between medications

    Learning empathy through virtual reality : Multiple strategies for training empathy-related abilities using body ownership Illusions in embodied virtual reality

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    Several disciplines have investigated the interconnected empathic abilities behind the proverb “to walk a mile in someone else’s shoes” to determine how the presence, and absence, of empathy-related phenomena affect prosocial behavior and intergroup relations. Empathy enables us to learn from others’ pain and to know when to offer support. Similarly, virtual reality (VR) appears to allow individuals to step into someone else’s shoes, through a perceptual illusion called embodiment, or the body ownership illusion. Considering these perspectives, we propose a theoretical analysis of different mechanisms of empathic practices in order to define a possible framework for the design of empathic training in VR. This is not intended to be an extensive review of all types of practices, but an exploration of empathy and empathy-related phenomena. Empathy-related training practices are analyzed and categorized. We also identify different variables used by pioneer studies in VR to promote empathy-related responses. Finally, we propose strategies for using embodied VR technology to train specific empathy-related abilities

    PRINCE-1: safety and efficacy of atazanavir powder and ritonavir liquid in HIV-1-infected antiretroviral-naïve and -experienced infants and children aged > 3 months to < 6 years

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    Artículo de publicación ISIIntroduction: PRINCE-1 is an ongoing prospective, international, multicentre, nonrandomized, two-stage clinical trial assessing safety and efficacy of once-daily atazanavir (ATV) powder boosted with ritonavir (RTV) liquid plus optimized dual nucleoside reverse-transcriptase inhibitor (NRTI) background therapy in antiretroviral (ARV)-naı¨ve and -experienced children with HIV-1 infection aged ]3 months to B6 years. Methods: Children with HIV-1 infection without prior ATV exposure and with a screening HIV-1 RNA ]1000 copies/mL were enrolled. The dosing of ATV powder, boosted with 80 mg RTV liquid, was based on three baseline weight bands (5 to B10 kg 150 mg, 10 to B15 kg 200 mg and 15 to B25 kg 250 mg). Results: Of the 56 treated patients, 46 completed 48 weeks of therapy, 67.9% were from Africa and 60.7% were ART-naı¨ve. Median ages at baseline were 6, 35 and 55 months, and proportions with HIV-1 RNA 100,000 were 85.7, 52.6 and 25% in the three baseline weight bands, respectively. No unexpected safety events occurred and no deaths were reported. Over 48 weeks, upper respiratory tract infections, diarrhoea, vomiting and Grade 3 to 4 hyperbilirubinaemia occurred in 35.7, 35.7, 28.6, and 9.4% of patients, respectively; five patients (8.9%) discontinued due to adverse events (AEs); and 11 patients (19.6%) experienced serious adverse events. At Week 48, using a modified intent-to-treat analysis (two patients were excluded because they switched to ATV capsules before Week 48), 61.1 and 74.1% of patients overall had an HIV-1 RNA level B50 copies/mL and B400 copies/mL, respectively. Virologic suppression rates increased across the lowest to highest baseline weight bands (47.6, 68.4 and 71.4% had HIV-1 RNA B50 copies/mL, and 66.7, 73.7 and 85.7% had HIV-RNA B400 copies/mL, respectively) but did not differ meaningfully between ARV-naı¨ve and -experienced patients. Overall, the median change from baseline in CD4 cell count was 363 cells/mm3, and the median change from baseline in CD4 percent was 7.5%. Conclusions: ATV powder boosted with RTV liquid once daily plus optimized dual NRTI background therapy was effective and well tolerated in this ART-naı¨ve or -experienced paediatric population aged ]3 months to B6 years. No unexpected safety findings compared with those from previous ATV paediatric and adult studies were identified.Bristol-Myers Squib
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