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Urban areas are subject to high human pressure and forthcoming enhanced hydrologic and climatic risks due to both city development and climate change. An asphalt concrete parking lot was instrumented in Nantes, France, to quantify the energy and hydrological responses of the surface to simulated rainfalls. The surface fluxes (precipitation, evaporation, radiation exchanges, sensible heat convection and conduction, runoff) were measured in situ and used to close the water budget with residual closure errors lower than 10%, depending on the surface evaporation retrieval method. The latent heat flux estimated from scintillometry measurements provided a better water budget closure than the direct eddy-correlation measurements. Runoff was the primary component of the water budget and represented around 80% of the total precipitation, compared to 17% for surface evaporation. The scintillometry method provided water evaporation time series at a 1-min time scale during the experiment. These series were used to characterize the rapid changes in the hydrological and energetic budgets of the asphalt surface after a precipitation event. During the drying phase the surface evaporation was significantly active, yielding 80% of the turbulent fluxes with a Bowen ratio of 0.25. [ABSTRACT FROM AUTHOR]

Abstract: The thermodynamic exchanges of the old city center of Marseilles during a summer period are analyzed with the SOLENE thermo-radiative model, using measurements of the UBL-ESCOMPTE experimental campaign in June–July 2001. The selected scene is an actual fragment of the urban canopy composed of 4 streets at right angles, with various 19th century houses and yards. The SOLENE software’s ability to simulate the heat and radiation exchanges of this urban district with the atmosphere is first evaluated by comparing simulation outputs with surface temperatures of individual roof and façade elements measured by infrared radiation thermometers and with integrated fluxes measured on top of a neighboring meteorological mast. This model assessment is reinforced by a sensitivity study to the interior building temperature, a variable of possible influence which is usually not measured in studies at the scale of an urban fragment or district. The flux sensor position influence on the comparison is also studied by introducing a virtual sensor in the simulated scene. The software is further used to analyze the behavior of individual surface elements of the scene with various orientations during a typical summer diurnal cycle. The contributions of the different surface classes (roofs, façades, streets, yards) to the upward radiation and heat fluxes to the atmosphere are then detailed for several canopy morphologies (H/W). [Copyright &y& Elsevier]

Abstract: This paper presents a validation of the thermo-radiative model SOLENE and its application for analysing the street canyon energy balance. The validation data were selected from the temperature and radiation measurements obtained during the JAPEX campaign, previously described by Idczak et al. : a set of four lines of steel containers buildings composing three parallel street canyons at an approximate 1:5 scale. Reference weather data and micrometeorological conditions within the canyon were measured. Numerical simulations were carried out using the meteorological measurements as model inputs. The simulated surface temperatures and radiation fluxes are compared with the measurements for a full week period, with a focus on a day with clear sky conditions. The street canyon energy balance analysis demonstrates that the most energetic surface was the street ground due to its thick surface layer of tar-coated gravels while the walls had a low heat capacity. The thermal radiation balance was negative for all canyon surfaces. The sensible heat was transferred mainly from the canyon surfaces to the ambient air, but also from the air to the ground in the morning. The effective albedo of the canyon had a diurnal value of 0.20–0.25, but dropped to 0.10 in the afternoon when the ground strongly transformed the direct and reflected solar radiation into sensible heat. This narrow street configuration enhanced solar radiation absorption and longwave radiation trapping. [Copyright &y& Elsevier]

This pilot study was part of a larger study aimed at characterizing the pharmacokinetic profile of intravenous nicotinamide adenine dinucleotide (NAD+) and measured cognitive performance following IV NAD+ in healthy male subjects. We hypothesized that IV NAD+ would improve cognitive performance scores as compared to baseline performance. Randomized, controlled study. Private mental health treatment center located in Springfield, LA. Fifteen healthy male participants (4 Saline/11 IV NAD+) between the ages of 30-55 met inclusion criteria. Participants received 5 consecutive days of IV NAD+ (750 mg/day) or saline infusions Researchers used the MicroCog™ Assessment of Cognitive Function to measure cognitive abilities on three levels: (Level 1) Attention, reaction time, memory, reasoning and spatial processing; (Level 2) Information processing speed and accuracy; and (Level 3) Global cognitive functioning and global cognitive proficiency. Participants completed baseline assessment (DAY 0) and repeated the task after the end of the IV infusion protocol (DAY 6). No differences between SAL and NAD+ groups were noted on DAY 0 in any of the 8 subtests evaluated. However, groups showed differences in the magnitude of improvement over days compared to their respective baselines. The NAD+ group reached significance on 6/8 tests, while the SAL group showed significant improvement on 2/8 tests. The findings when compared to respective baseline performance scores indicated a greater magnitude of change over and above "practice effects". These results combined with case reports in Parkinson's disease patients suggest that implementation of a standardized cognitive assessment is a practical and effective way to establish efficacy of IV NAD+ treatment for clinical conditions involving cognitive impairment Dr. R. Mestayer is a director of NAD+ Research Inc., and medical director of the Springfield Wellness Center that uses IV NAD+ as a clinical therapy. Dr. Broom-Gibson received consulting fees from NAD+ Research Inc. [ABSTRACT FROM AUTHOR]

Abstract: Deposition velocities of aerosol on building and monument vertical surfaces have scarcely been documented and modeled so far. A methodology is proposed based on simultaneous measurements of artificial aerosol tracer fluorescein emissions, concentrations and depositions, and of high frequency turbulent variables. The results are compared to year-long deposition of 7Be, a naturally produced airborne radioactive particle tracer. A three-dimensional simulation of the turbulent flow and concentration fields in the vicinity of the wall specifies the flow structure responsible for deposition on the facade. It also allows comparison of the measured fluorescein deposition velocities with two semi-empirical models. [Copyright &y& Elsevier]

Abstract: The measurements of surface temperature are prone to important directional anisotropy in relation to the structure of the urban canopy and the radiative and energy exchanges inside it. Following the work of Lagouarde et al. 2010 that describes the daytime conditions, this paper focuses on the experimental analysis and modelling of the nighttime directional anisotropy. An extensive data set of airborne thermal infrared (TIR) measurements was collected over the city of Toulouse, France in the framework of the CAPITOUL project (Masson et al., 2008). The TIR measurements use a pair of thermal cameras equipped with wide angle lenses installed aboard a small aircraft. Three flights were made between 21:45 and 23:15 UTC, one in autumn and 2 in winter during 2004 and 2005 intensive operation periods (IOPs). The experimental results show that (i) the nighttime TIR directional anisotropy remains lower than 1°C for zenithal view angles up to 50°, and (ii) the nighttime anisotropy is insensitive to the azimuthal viewing direction. A modelling approach that combines a simplified 3D representation of the urban canopy with 2 energy transfer models, TEB and SOLENE, is then proposed. It confirms the experimental results quite well. Possible uncertainties on the geometry of the canopy and on most important thermo-radiative surface parameters are shown to have only little impact on the modelled TIR directional anisotropy. The time evolution of TIR anisotropy throughout night is simulated: for the fall and winter conditions studied the effects of thermal inertia completely vanish about 3 to 4h after sunset, and the anisotropy never exceeds 2°C up to 60° zenithal view angles. [Copyright &y& Elsevier]

Abstract: Measurements of thermal infrared (TIR) directional anisotropy (difference between off-nadir and nadir brightness temperatures) performed over the city of Toulouse using a method based on the use of 2 airborne TIR cameras are presented. Results from 3 flights at different times during a summer day (July 15th 2004) and from 1 flight in winter (February 25th 2005) all confirm important anisotropy (up to 10°C) and hot spot effects as previously reported in literature. A simple simulation approach is then proposed. It is based on the aggregation in any viewing direction of 6 directional temperatures (sunlit/shaded walls/streets/roofs) weighted by their corresponding surface ratios within the scene viewed. The city is described by 18 canyon streets oriented in all directions by 10° steps and the 6 temperatures are determined by integrating simulations of the energy balance model SOLENE repeated for the 18 canyon streets. The surface ratios are computed from images of the studied area generated with the POV-Ray software (Persistence of Vison Raytracer, http://www.povray.org/). This method is described in detail. The modelled anisotropy compares favourably with the measurements on all dates, despite a systematic underestimation ranging between 15 and 30%. The possible sources of discrepancy including sensitivity to the aspect ratio and to the surface parameters and possible impact of microscale structures are briefly discussed and several improvements of the modelling system are suggested. [Copyright &y& Elsevier]