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The aim of this study was to evaluate the feasibility of kinetic analysis of cerebrospinal fluid (CSF) using 17O-labeled water tracer. Four subjects (two idiopathic normal pressure hydrocephalus (iNPH) and two possible AD dementia patients) were prospectively included. Injectable formulation of 17O-labeled water containing 10 mol% of H 2 17O (PSO17), was intrathecally administered to the subjects with the lateral decubitus position between the 3rd and 4th lumbar vertebrae. MRI acquisitions were performed in four-time points, before PSO17 administration, 1, 8, and 24 h after PSO17 administration. The 3-dimensional fast spin echo sequence was used. After image registration for all four-time points data, polygonal regions of interest (ROIs) were set in the 14 regions to obtain the signal intensity of CSF. Each signal intensity within the ROI was converted to 17O concentration [%]. The peak concentration at one hour after administration, the slope of concentration changes after PSO17 administration [%/s], and the root mean square error (RMSE) for evaluating the performance of a fitting were calculated. There was no significant difference in peak concentration between the iNPH and AD group. The slope in the AD group (−2.25 ± 1.62 × 10−3 [%/h]) was significantly smaller than in the iNPH group (−1.21 ± 2.31 × 10−3 [%/h]), which suggests the speed of CSF clearance in the iNPH group was slower than AD group. The RMSE indicating the fit to the concentration change in the AD group (4.86 ± 4.74 × 10−3) was also significantly smaller than in the iNPH group (8.64 ± 7.56 × 10−3). The kinetic evaluation of CSF using 17O-labeled water was feasible, and this preliminary study suggests that the differentiation of iNPH and possible AD dementia can be achieved using this method. [ABSTRACT FROM AUTHOR]

• Neutronography was employed for the investigation of the interaction between consolidants and Pietra di Lecce limestone. • Water motion inside the investigated limestones was visualized. • The effectiveness of the consolidants as protective agents against several artificial weathering tests was demonstrated. • A better performance of nanosilica with respect to nanolime was revealed. • The data could represent methodological proposal scheme in view of a proper restoration/conservation procedure. In this work a combined laboratory-based and neutronographic investigation was carried out on a type of limestone, known as Pietra di Lecce stone, widely used in Italian Baroque as construction material. The limestone was treated with two different commercially-available coatings, namely nanosilica and nanolime, and artificially weathered by salt crystallization and temperature/relative humidity jumps. The aim was to provide an experimental evidence of the protective and consolidating effectiveness of the two treatments by looking at the water absorption process occurring inside the pore network of the analyzed stones. The analysis of the wetting front position revealed significant variations in the water absorption kinetics among the investigated samples, suggesting different mechanisms of interaction between the inorganic consolidants and the underlying bulk stone. Finally, a quantitative evaluation of the best effectiveness of the two products was addressed, particularly useful in view of an appropriate choice of restoration procedures to be applied to building materials. [ABSTRACT FROM AUTHOR]

Neutron radiography (NR) was here applied to study the effects of two different commercially available consolidants on the water absorption properties in a particular type of limestone (biocalcarenite), known as Pietra d'Aspra stone, which is one of the most extensively used lithotypes in Sicilian Baroque buildings. Our attention was mainly focused on the evaluation, using a fast and nondestructive visualization of water motion through capillarity, of the effectiveness of such layers as consolidating agents in view of preserving and maintaining both old and modern structures. The biocalcarenite was treated with nanosilica (Nano Estel®) and nanolime (CaLoSil®) by brushing it until full saturation, and then artificially weathered by salt crystallization and temperature/relative humidity jumps. Liquid distribution and height of the water front were monitored as a function of time. Significant differences in the water suction behavior among all the investigated samples were highlighted, which allowed us to gain insight into the coating/substrate interaction mechanisms which regulate the fluid mobility inside the porous network of the limestone. [ABSTRACT FROM AUTHOR]

Neutron radiography (NR) was here applied to study the effects of two different commercially available consolidants on the water absorption properties in a particular type of limestone (biocalcarenite), known as Pietra d’Aspra stone, which is one of the most extensively used lithotypes in Sicilian Baroque buildings. Our attention was mainly focused on the evaluation, using a fast and nondestructive visualization of water motion through capillarity, of the effectiveness of such layers as consolidating agents in view of preserving and maintaining both old and modern structures. The biocalcarenite was treated with nanosilica (Nano Estel®) and nanolime (CaLoSil®) by brushing it until full saturation, and then artificially weathered by salt crystallization and temperature/relative humidity jumps. Liquid distribution and height of the water front were monitored as a function of time. Significant differences in the water suction behavior among all the investigated samples were highlighted, which allowed us to gain insight into the coating/substrate interaction mechanisms which regulate the fluid mobility inside the porous network of the limestone.

Highlights: [•] Base coat sorption and top coat permeability define response time to fluctuations. [•] Damped rapid fluctuations, if the period is faster than the response time. [•] Response time may range from few hours at RH<50% to several days at RH>50%. [•] No hygric stresses in base coat/top coat systems in accelerated weathering. [Copyright &y& Elsevier]

The article discusses the results of a study examining the effect of leaves based diet from Dicanthium annulatum species on goats' eating pattern, rumen metabolites, and nutrient utilization. The authors performed a digestion and metabolism trial and rumen liquor collection to analyze the nitrogen balance, food intake, and nutrient utilization. The results showed that goats had higher eating pattern during the first and fourth hour of feeding. The water kinetics of goats is also analyzed.

Purpose: The feasibility of steady-state sequences for 17 O imaging was evaluated based on a kinetic analysis of the brain parenchyma and cerebrospinal fluid (CSF)., Materials and Methods: The institutional review board approved this prospective study with written informed consent. Dynamic 2D or 3D steady-state sequences were performed in five and nine participants, respectively, with different parameters using a 3T scanner. During two consecutive dynamic scans, saline was intravenously administered for control purposes in the first scan, and 20% 17 O-labeled water (1 mL/Kg) was administered in the second scan. Signal changes relative to the baseline were calculated, and kinetic analyses of the curves were conducted for all voxels. Region of interest analysis was performed in the brain parenchyma, choroid plexus, and CSF spaces., Results: Average signal drops were significantly larger in the 17 O group than in the controls for most of the imaging parameters. Different kinetic parameters were observed between the brain parenchyma and CSF spaces. Average and maximum signal drops were significantly larger in the CSF spaces and choroid plexus than in the brain parenchyma. Bolus arrival, time to peak, and the first moment of dynamic curves of 17 O in the CSF space were delayed compared to that in the brain parenchyma. Significant differences between the ventricle and subarachnoid space were also noted., Conclusion: Steady-state sequences are feasible for indirect 17 O imaging with reasonable temporal resolution; this result is potentially important for the analysis of water kinetics and aquaporin function for several disorders.