14C]2-deoxyglucose uptake in the brain of the ring dove (Streptopelia risoria). II. Differential uptake at the onset of incubation

Brain areas involved in the expression of incubation behaviour were identified in male ring dove at the onset of incubation using quantitative [14C]2-deoxyglucose (2DG) autoradiography. The uptake of 2DG in twenty-eight areas found in the hypothalamus and thalamus, and six areas in the forebrain were compared in control non-breeding and incubating birds. Although 2DG utilisation varied significantly between brain areas, significant differences between non-breeding males and incubating males were observed only in 4 of them. These were the nucleus tuberis, nucleus preopticus medialis, nucleus ovoidalis and paleostriatum primitivum. The uptake of 2DG was increased at the onset of incubation in the nucleus tuberis, nucleus preopticus medialis and nucleus ovoidalis and decrease in the paleostriatum primitivum. These findings are consistent with the hypothesis that these brain areas play a role in the initiation of incubation behaviour.     

Monitoring cell movements and volume changes with pulse-mode scanning ion conductance microscopy

Here we describe the use of pulse‐mode scanning ion conductance microscopy (SICM) to observe volume changes and cell membrane movements during the locomotion of cultured cells in the range of minutes to several hours. The microscope is based on the pulse‐mode SICM previously developed for stable imaging of single cells in culture. Our instrument uses current pulses to control the distance between cell surface and electrode tip as well as a back‐step mode to prevent contact of tip and membrane during lateral movements of the probe. We performed repeated scans of cell surfaces using feedback‐controlled piezoactors to position the electrode. Using patch‐clamp‐type electrode tips the height of cells could reproducibly be measured with a standard deviation of 50 nm. To quantify and separate changes in cell position and volume occurring between consecutive scans, a program was written to subtract images and calculate volume changes. Examples of repeated scans show that membrane movements in the range of 30 min to a few hours can be quantitatively monitored with a lateral resolution of 500 nm using difference images and that faster movements in the range of minutes can be recorded at defined cell sections using the line scan mode. Difference images indicate that volume changes can affect cell surfaces inhomogeneously, emphazising the role of the cytoskeleton in the stabilization of cell shape.     

Measuring validity in sensory analysis

Two methods for assessor evaluation are demonstrated, both based on graphical techniques: plots of an assessor's ability to detect differences vs. his/her repeatability, and the ‘egg-shell plot’ which highlights an assessor's agreement with the panel's rankings. The methods presented in this paper are modifications of already established methods in the area. All methods are illustrated by an example from sensory profiling of beef boullion.     

WASP: A WSI Associative String Processor

ASP (Associative String Processor) modules (and support software) comprise highly-versatile and fault-tolerant building-blocks for the simple construction of dynamically-reconfigurable low-MIMD/high-SIMD second-generation Massively Parallel Processor (MPP) systems. Indeed, based on state-of-the-art microelectronics and packaging technologies, ASP modules constitute a family of packaged MPP configurations for the cost-effective implementation of highly-compact application-specific high performance information processing systems.Based on scalar-vector content-matching rather than location addressing, ASP substrings comprise homogeneous fine-grain SIMD MPP structures, which, in operation, execute a form of set processing (i.e. a sequence of scalar-vector and vector-vector processes) on relevant data. Moreover, application flexibility enables simple tailoring of parallel processing power to match user requirements.WASP devices are WSI (Wafer Scale Integration) implementations of ASP substrings and, as such, constitute fundamental building blocks for the assembly of ASP modules. Exploiting either monolithic or hybrid 1 m CMOS WSI technologies, 8,192-processor WASP devices would enable the assembly of 65,536-processor SEM-E compatible ASP modules achieving 10 Tera-OPS/ft³, 1 Giga-OPS/W and 1 Mega-OPS/$ in cost-effectiveness.The paper discusses second-generation MPP design targets and describes ASP modules for real-time signal and data processing applications. In particular, the paper focuses on the architecture, operation, and implementation of the WASP device and reports on the progress of its development.     

Heterogeneous production of Cl2 from particulate chloride: Effects of composition and relative humidity

Reactions initiated by chlorine atoms can enhance the formation of ozone (O₃) and secondary organic aerosol (SOA) in the troposphere. Environmental chamber experiments were conducted to quantify heterogeneous Cl₂ production from NH₄Cl and NaCl particles exposed to O₃ and hydroxyl radicals (?OH). Observations are inconsistent with models of Cl₂ production resulting solely from surface‐mediated reactions of ?OH and suggest that O₃ plays a significant role. The production of Cl₂ increased with relative humidity and decreased in the presence of SOA or nitric oxides (NO_x). Heterogeneous reactive uptake coefficients for the production of Cl₂ from O₃ on pure NH₄Cl ( ) averaged 1.4 ± 1.0 × 10^?3. Cl₂ production was six times more efficient on NH₄Cl aerosol than on NaCl aerosol. Model calculations under atmospheric conditions suggest this heterogeneous Cl₂ production could increase peak daily O₃ concentrations by over 10%. © 2018 American Institute of Chemical Engineers AIChE J, 64: 3151–3158, 2018     

Tridimensional ultrastructure of perfusion fixed gastrointestinal epithelial cells by high resolution scanning electron microscopy

Improvements in the design of modern scanning electron microscopes (SEM) and new methods of specimen preparation incorporating chemical removal of the cytosol and cytoskeleton, now make it possible to view cells and their organelles in three dimensions (3D) at high magnification. In this experiment, high resolution SEM (HRSEM) utilizing new methods of tissue preparation was used to study the intracellular structures of the mouse ileum. In addition, in vivo intestinal perfusion was used to further enhance cellular preservation. Using these modifications it was possible to visualize, in 3D, the fine structure of intestinal epithelial cells and intracellular organelles such as the nucleus, mitochondria, endoplasmic reticulum, and Golgi complex, as well as microvilli and cell membrane. Whole mitochondria appeared as irregularly shaped organelles which contained tubular cristae. Plate-like cristae were not observed. The brush border was found to be a closely packed array of cylindrical projections. The extensive folding and structural intricacy of lateral cell membranes between absorptive cells could only be appreciated by viewing this tissue with 3D HRSEM. The use of HRSEM to study 3D ultrastructure of cells and their organelles will improve our understanding of the structure-function relationships in both the healthy and diseased gastrointestinal tract.     

Virtual Society: Collaboration in 3D Spaces on the Internet

The Virtual Society (VS) project is a long term research initiativethat is investigating the evolution of the futureelectronic society. Our vision for this electronic societyis a shared 3D virtual world where users, from homes and offices, canexplore, interact and work. Our first implementation of aninfrastructure to support our investigation is known asCommunityPlace and has been developed to support large-scale shared 3D spaces onthe Internet using the Virtual Reality Modeling Language (VRML). Obviously, such an ambitious project cutsacross many different domains. In this paper we outline thegoals of the Virtual Society project, discuss the architecture andimplementation of CommunityPlace with particular emphasis on Internetrelated technologies such as VRML and present our views on the role ofVRML and the Internet to support large-scale shared 3D spaces.     

A school-based intervention improved dietary intake outcomes and reduced waist circumference in adolescents: a cluster randomized controlled trial

Background

In Ecuador, adolescents’ food intake does not comply with guidelines for a healthy diet. Together with abdominal obesity adolescent’s inadequate diets are risk factors for non-communicable diseases. We report the effectiveness of a school-based intervention on the dietary intake and waist circumference among Ecuadorian adolescents.

Methods

A pair-matched cluster randomized controlled trial including 1430 adolescents (12–14 years old) was conducted. The program aimed at improving the nutritional value of dietary intake, physical activity (primary outcomes), body mass index, waist circumference and blood pressure (secondary outcomes). This paper reports: (i) the effect on fruit and vegetable intake, added sugar intake, unhealthy snacking (consumption of unhealthy food items that are not in line with the dietary guidelines eaten during snack time; i.e. table sugar, sweets, salty snacks, fast food, soft drinks and packaged food), breakfast intake and waist circumference; and, (ii) dose and reach of the intervention. Dietary outcomes were estimated by means of two 24-h recall at baseline, after the first 17-months (stage one) and after the last 11-months (stage two) of implementation. Dose and reach were evaluated using field notes and attendance forms. Educational toolkits and healthy eating workshops with parents and food kiosks staff in the schools were implemented in two different stages. The overall effect was assessed using linear mixed models and regression spline mixed effect models were applied to evaluate the effect after each stage.

Results

Data from 1046 adolescents in 20 schools were analyzed. Participants from the intervention group consumed lower quantities of unhealthy snacks (?23.32 g; 95% CI: ?45.25,-1.37) and less added sugar (?5.66 g; 95% CI: ?9.63,-1.65) at the end of the trial. Daily fruit and vegetable intake decreased in both the intervention and control groups compared to baseline, albeit this decrease was 23.88 g (95% CI: 7.36, 40.40) lower in the intervention group. Waist circumference (?0.84 cm; 95% CI: ?1.68, 0.28) was lower in the intervention group at the end of the program; the effect was mainly observed at stage one. Dose and reach were also higher at stage one.

Conclusions

The trial had positive effects on risk factors for non-communicable diseases, i.e. decreased consumption of unhealthy snacks. The program strategies must be implemented at the national level through collaboration between the academia and policy makers to assure impact at larger scale.

Trial registration

ClinicalTrial.gov-NCT01004367.

     

Biofilm formation in Haas palatal expanders with and without use of an antimicrobial agent: an in situ study

Orthodontic appliances causes specific alterations in oral environment, including reduction of pH, increase of dental biofilm and elevation of salivary microbial levels, causing an increased risk for dental caries. This study evaluated, using microbial culture and scanning electron microscopy (SEM), the in situ contamination by mutans streptococci (MS) of different surfaces of Haas palatal expanders with and without use of chlorhexidine gluconate mouthrinses (CHX). Thirty‐four patients were randomly assigned to two groups (n = 17/group), using placebo (Group I) and 0.12% CHX (Group II—Periogard^®) mouthrinses twice a week. After 4 months, appliances were submitted to microbiological processing and after fragments were analyzed by SEM. Mann–Whitney U test (α = 5%) was used to assess differences between groups on the appliances' different surfaces and to compare the contamination on the free and nonfree surfaces of these components. There was no difference (p = 0.999) between groups regarding the number of MS colonies/biofilms on the nonfree surfaces, which showed intense contamination. However, free surfaces of Group II presented less contamination (p < 0.001) than those of Group I in all appliances' components. Results of the microbial culture were confirmed by SEM. Use of 0.12% CHX was effective in reducing the formation of MS colonies/biofilms on free surfaces of Haas expanders, in situ.