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This paper describes a set of tools developed by different authors that can be applied in the Pre-Development of Product Development Process in food industries. Product Development Process (PDP) is considered increasingly important to company competitiveness. The management of this activity is critical to detect customers needs and to offer products according to them, in order to optimize company resources and increase its profits. At food industry, this process is especially relevant due to the increase of products offered in the market and the reduction of their life cycles. Despite the existence of studies that seek to standardize the process of food product development, implementation of PDP models is incipient. Rozenfeld et al (1) propose a model that outlines the process in macrophases, phases and tools, that allows the implementation of new product development. This model was adapted by Penso (2) according to food industry characteristics. Both contributions have been taken as reference for this investigation. Among the phases, it underscores Pre-Development macrophase, which involves planning portfolio organization in the context of its strategic plan. Its importance lies in the decisions made along the stage, that guide the process of further development and may determine the future business scenario. This indicates the need for appropriate tools in order to manage efficiently this macrophase. This paper describes different techniques and tools available in the literature related to PDP and structure them according to the activities developed in the Pre-Development macrophase in food industries.

PURPOSE: The graphical processing unit (GPU) on modern graphics cards offers the possibility of accelerating arithmetically intensive tasks. By splitting the work into a large number of independent jobs, order-of-magnitude speedups are reported. In this article, the possible speedup of PLATO's ray tracing algorithm for dose calculations using a GPU is investigated. METHODS: A GPU version of the ray tracing algorithm was implemented using NVIDIA's CUDA, which extends the standard C language with functionality to program graphics cards. The developed algorithm was compared based on the accuracy and speed to a multithreaded version of the PLATO ray tracing algorithm. This comparison was performed for three test geometries, a phantom and two radiotherapy planning CT datasets (a pelvic and a head-and-neck case). For each geometry, four different source positions were evaluated. In addition to this, for the head-and-neck case also a vertex field was evaluated. RESULTS: The GPU algorithm was proven to be more accurate than the PLATO algorithm by elimination of the look-up table for z indices that introduces discretization errors in the reference algorithm. Speedups for ray tracing were found to be in the range of 2.1-10.1, relative to the multithreaded PLATO algorithm running four threads. For dose calculations the speedup measured was in the range of 1.5-6.2. For the speedup of both the ray tracing and the dose calculation, a strong dependency on the tested geometry was found. This dependency is related to the fraction of air within the patient's bounding box resulting in idle threads. CONCLUSIONS: With the use of a GPU, ray tracing for dose calculations can be performed accurately in considerably less time. Ray tracing was accelerated, on average, with a factor of 6 for the evaluated cases. Dose calculation for a single beam can typically be carried out in 0.6-0.9 s for clinically realistic datasets. These findings can be used in conventional planning to enable (nearly) real-time dose calculations. Also the importance for treatment optimization techniques is evident

A new version of the Weiland model has been used in predictive JETTO simulations of toroidal rotation. The model includes a self-consistent calculation of the toroidal momentum diffusivity (chi(phi)) which contains both diagonal and non-diagonal (pinch) contributions to the momentum flux. Predictive transport simulations of JET H-mode, L-mode and hybrid discharges are presented. It is shown that experimental temperatures and toroidal velocity were well reproduced by the simulations. The model predicts the ion heat diffusivity (chi(i)) to be larger than the momentum diffusivity and it gives Prandtl numbers (Pr = chi(phi)/chi(i)) between 0.1 and 1. The Prandtl numbers are often, depending on the plasma conditions, predicted to be significantly smaller than unity. This is in accordance with experimental findings.

Purpose: One of the major issues in high intensity focused ultrasound ablation of abdominal lesions is obstruction of the ultrasound beam by the thoracic cage. Beam shaping strategies have been shown by several authors to increase focal point intensity while limiting rib exposure. However, as rib obstruction leaves only part of the aperture available for energy transmission, conserving total emitted acoustic power, the intensity in the near-field tissues inherently increases after beam shaping. Despite of effective rib sparing, those tissues are therefore subjected to increased risk of thermal damage. In this study, for a number of clinically representative intercostal sonication geometries, modeling clinically available hardware, the effect of beam shaping on both the exposure of the ribs and near-field to acoustic energy was evaluated and the implications for the volumetric ablation rate were addressed. Methods: A relationship between rib temperature rise and acoustic energy density was established by means of in vivo MR thermometry and simulations of the incident acoustic energy for the corresponding anatomies. This relationship was used for interpretation of rib exposure in subsequent numerical simulations in which rib spacing, focal point placement, and the focal point trajectory were varied. The time required to heat a targeted region to 65 degrees C was determined without and with the application of beam shaping. The required sonication time was used to calculate the acoustic energy density at the fat-muscle interface and at the surface of the ribs. At the fat-muscle interface, exposure was compared to available literature data and rib exposure was interpreted based on the earlier obtained relation between measured temperature rise and simulated acoustic energy density. To estimate the volumetric ablation rate, the cool-down time between periods of energy exposure was estimated using a time-averaged power limit of 100 kJ/h. Results: At the level of the ribs, the temperature rise-energy density proportionality constant was estimated to be 6.0-7.6 degrees C/(J/mm(2)). Beam shaping by the geometric shadow method typically reduces the acoustic intensity a factor of 2, considering the 1 cm(2) with the highest exposure. For a 4 mm diameter circular sonication trajectory, the near-field energy limit of 2.5 J/mm(2) was exceeded for all considered geometries. The estimated rib temperature was in all but one (sonication 50 mm behind the ribs, with 15 mm rib spacing and a 4 mm diameter circular sonication trajectory) of the considered scenarios within acceptable limits. For those sonication scenarios where a single sonication is considered safe both in terms of near-field as well as rib heating, volumetric ablation rates in the order of 1 ml/h are estimated. Conclusions: Intercostal sonication is associated with an increased risk of near-field overheating. This risk is strongly dependent on the considered rib spacing, the placement of the focus behind the ribs, and the selected sonication trajectory. For the hardware under simulation, obstruction by the thoracic cage renders ablations of clinically relevant volumes within a practical time-frame unfeasible in a large part of the liver. Improvements maybe expected from transducer designs with a larger active surface and/or nonlinear sonication strategies. (C) 2015 American Association of Physicists in Medicine.

International audience; Local drug delivery in oncology aims at depositing high doses of anticancer agents while limiting their toxic side effects. Biological barriers, such as cell plasma membranes, hinder their delivery and requires strategies to address this challenge. Previously [1], we demonstrated the feasibility to monitor in real-time, with dynamic fluorescence microscopy, the in-tracellular delivery of a hydrophilic model drug mediated by ultrasound (US), and to quantify the pharmacokinetic parameters derived from a two-compartment model. We evaluate here the impact of the photobleaching (PB) effect experimentally , and compute the PB-corrected uptake kinetics.

An experimental study in plasma rotation and momentum transport was carried out at JET. The toroidal rotation profile was found to scale approximately with that of the ion temperature. However, significant deviations from this were found in high density ELMy H-mode discharges, which had broader rotation profiles. A rotation database analysis showed the variation of the dimensionless Mach number with respect to the plasma scenario. For predominantly NBI heated discharges the Mach number was found to be in the range of 0.3–0.45. Larger Mach numbers were observed in type I ELMy H-modes, while scenarios exhibiting type III ELMs or L-mode had lower Mach numbers. Advanced scenarios often showed a significant increase in the central Mach number when an internal transport barrier formed. A detailed study was done to investigate the Prandtl number, P r , defined as the ratio between momentum and ion heat diffusivity. Generally the Prandtl number was found to be significantly below unity, e.g. 0.18 < P r < 0.35. Although it is often predicted that momentum and heat diffusivity are equal in ITG dominated plasma, also for high density ELMy H-mode discharges with temperature profiles close and above the ITG threshold, the Prandtl number was P r ∼ 0.3.

PURPOSE: Hyperthermia treatment planning (HTP) potentially provides a valuable tool for monitoring and optimization of treatment. However, one of the major problems in HTP is that different sources of uncertainty degrade its reliability. Perfusion uncertainty is one of the largest uncertainties and hence there is an ongoing debate whether optimization should be limited to power-based strategies. In this study a systematic analysis is carried out addressing this question. METHODS: The influence of perfusion uncertainty on optimization was analyzed for five patients with cervix uteri carcinoma heated with the AMC-8 70 MHz phased-array waveguide system. The effect of variations (up to +/- 50%) in both the muscle and tumor perfusion level was investigated. For every patient, reference solutions were calculated using constrained temperature-based optimization for 25 different and known perfusion distributions. Reference solutions were compared to those found by temperature-based optimization using standard perfusion values and four SAR-based optimization methods. The effect of heterogeneity was investigated by creating 5 x 100 perfusion distributions for different levels of local variation (+/- 25% and +/- 50%) and scale (1 and 2 cm). Here the performance of the temperature-based optimization method was compared to a SAR-based method that showed good performance in the previous analysis. RESULTS: Solutions found with temperature-based optimization using a deviating perfusion distribution during optimization were found within 1.0 degrees C from the true optimum. For the SAR-based methods, deviations up to 2.9 degrees C were found. The spread found in these deviations was comparable, typically 0.5-1.0 degrees C. When applying intramuscle variation to the perfusion, temperature-based optimization proved to be the best strategy in 95% of the evaluated cases applying +/- 50% local variation. CONCLUSIONS: Temperature-based optimization proves to be superior to SAR-based optimization both under variation of perfusion level as well as under the application of intratissue variation. The spread in achieved temperatures is comparable. These results are valid under the assumption of constant perfusion at hyperthermic levels. Although similar results are expected from models including thermoregulation, additional analysis is required to confirm this. In view of uncertainty in tissue perfusion and other modeling uncertainties, the authors propose feedback guided temperature-based optimization as the best candidate to improve thermal dose delivery during hyperthermia treatment

In regional hyperthermia, optimization is useful to obtain adequate applicator settings. A speed-up of the previously published method for high resolution temperature based optimization is proposed. Element grouping as described in literature uses selected voxel sets instead of single voxels to reduce computation time. Elements which achieve their maximum heating potential for approximately the same phase/amplitude setting are grouped. To form groups, eigenvalues and eigenvectors of precomputed temperature matrices are used. At high resolution temperature matrices are unknown and temperatures are estimated using low resolution (1 cm) computations and the high resolution (2 mm) temperature distribution computed for low resolution optimized settings using zooming. This technique can be applied to estimate an upper bound for high resolution eigenvalues. The heating potential of elements was estimated using these upper bounds. Correlations between elements were estimated with low resolution eigenvalues and eigenvectors, since high resolution eigenvectors remain unknown. Four different grouping criteria were applied. Constraints were set to the average group temperatures. Element grouping was applied for five patients and optimal settings for the AMC-8 system were determined. Without element grouping the average computation times for five and ten runs were 7.1 and 14.4 h, respectively. Strict grouping criteria were necessary to prevent an unacceptable exceeding of the normal tissue constraints (up to approximately 2 degrees C), caused by constraining average instead of maximum temperatures. When strict criteria were applied, speed-up factors of 1.8-2.1 and 2.6-3.5 were achieved for five and ten runs, respectively, depending on the grouping criteria. When many runs are performed, the speed-up factor will converge to 4.3-8.5, which is the average reduction factor of the constraints and depends on the grouping criteria. Tumor temperatures were comparable. Maximum exceeding of the constraint in a hot spot was 0.24-0.34 degree C; average maximum exceeding over all five patients was 0.09-0.21 degree C, which is acceptable. High resolution temperature based optimization using element grouping can achieve a speed-up factor of 4-8, without large deviations from the conventional method

Since 1980, More Exercise for Seniors (MBvO in Dutch) has provided a number of special physical activities for the elderly. The aim is to improve social participation and integration, and to prevent a need for care. Despite the fact that MBvO has been active for more than 25 years, and weekly 300,000 people participate in gymnastics, swimming, dancing, etc, no effect on fitness and health has been proven to date. The study was carried out in two regions: Drenthe and Zuid-Holland. Using the GALM (Groningen Active Living Model) method, 4600 independently living people aged 65 years and older were asked to participate in a motor fitness test. Of the 721 people who participated, 386 (the least fit) were invited to take part in the study. They were than randomly divided into an experimental and a control group. The experimental group did gymnastics once or twice a week. The control group received a health educational program. Assessments were carried out at pretest and posttest (10 weeks). In the groups offered MBvO gymnastics once a week, no effects were found on subjective health, physical performance or quality of life and only minor effects on physical fitness. In the groups offered MBvO gymnastics twice a week, some beneficial quality of life effects were found in the least physically active people at baseline. It is recommended that the frequency and intensity of the regular MBvO gymnastics should be increased, to emphasize the importance of health education, and that relatively inactive and older individuals (70+) should be recruited.

The assessment of fitness is a component of a national project aimed at the enhancement of physical avtivity among sedentary older adults, aged 55-65 year in the Netherlands. Deterioration in physical functioning may be improved through an exercise programme. Research showed that enhancement of physical activity results in improved fitness, increased functional ability and health-related quality of life. Scientific results of the association between exercise and physical fitness in older adults is not sufficiently evidence-based in the Netherlands. In order to support health policy interventions 5.584 fitness tests of sedentary older adults were analyzed. The fitness was assessed by the Groninger Fitnesstest for Elderly (GFE). The analysis of physical fitness in sedentary older adults showed a lower fitness status among the age group 55-65 of age and women. Health risk factors such as overweight and having a chronic disease explained 88% of the variance between a low fitness and a high fitness profile

The assessment of fitness is a component of a national project aimed at the enhancement of physical avtivity among sedentary older adults, aged 55-65 year in the Netherlands. Deterioration in physical functioning may be improved through an exercise programme. Research showed that enhancement of physical activity results in improved fitness, increased functional ability and health-related quality of life. Scientific results of the association between exercise and physical fitness in older adults is not sufficiently evidence-based in the Netherlands. In order to support health policy interventions 5.584 fitness tests of sedentary older adults were analyzed. The fitness was assessed by the Groninger Fitnesstest for Elderly (GFE). The analysis of physical fitness in sedentary older adults showed a lower fitness status among the age group 55-65 of age and women. Health risk factors such as overweight and having a chronic disease explained 88% of the variance between a low fitness and a high fitness profile

OBJECTIVES: To determine the effects of gymnastics on the health related quality of life (HRQoL) and functional status of independently living people, aged 65 to 80 years. Gymnastics formed part of the More Exercise for Seniors (MBvO in Dutch) programme, a group based exercise programme for older adults in the Netherlands. It has been widely implemented since 1980.DESIGN: Randomised controlled trial with pretest and post-test measurements.INTERVENTION: The exercise programme given by experienced instructors lasted 10 weeks and was given weekly (MBvO1; n = 125, six groups) or twice weekly (MBvO2; n = 68, six groups). The control group (n = 193) was offered a health education programme.SETTING: Community dwelling of older people, with a comparatively low level of fitness as assessed with the Groningen Fitness test for the Elderly.RESULTS: No significant effects were found on the HRQoL (Vitality Plus Scale, TAAQoL, and RAND-36) and the functional status (Physical Performance Test and the Groningen Activity Restriction Scale). The MBvO2 group, with a low level of physical activity at baseline, showed the only improvement found on the Vitality Plus Scale (F = 4.53; p = 0.01).CONCLUSIONS: MBvO gymnastics once a week did not provide benefits in HRQoL and functional status after 10 weeks. However, participants with a low level of physical activity may benefit from MBvO gymnastics if they participate twice a week. To improve the health of the general public, sedentary older adults should be recruited and encouraged to combine MBvO with the health enhancing physical activity guidelines.