70 research outputs found
Thermal comfort in residential buildings with water based heating systems: a tool for selecting appropriate heat emitters when using µ-cogeneration
As a consequence of people becoming more aware of their impact on the environment, there is an increasing demand for low energy buildings. Forced by regulation, building envelopes are improving and heating and cooling systems with higher efficiencies are being installed. The public are willing to embrace these new technologies, as long as they do not affect the quality of their indoor environment. In this paper, an introduction to research on the realisation of the indoor thermal comfort in residential buildings with water based, low-energy heating systems is given. The basis for this work is a more realistic definition of comfort temperatures for residential buildings. Subsequently, appropriate heat emitters to realise that thermal comfort in an efficient way are identified, taking into account the limitations of the production system under consideration. An example of a µ-cogeneration system is presented as a case study
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The Coupling of ESP-R and Genopt: A Simple Case Study
This paper describes and demonstrates how to use the optimization program GenOpt with the building energy simulation program ESP-r. GenOpt, a generic optimization program, minimises an objective function that is evaluated by an external simulation program. It has been developed for optimization problems that are computationally expensive and that may have nonsmooth objective functions. ESP-r is a research oriented building simulation program that is well validated and has been used to conduct various building energy analysis studies. In this paper, the necessary file preparations are described and a simple optimization example is presented
Which Compound to Select in Lead Optimization? Prospectively Validated Proteochemometric Models Guide Preclinical Development
In quite a few diseases, drug resistance due to target variability poses a serious problem in pharmacotherapy. This is certainly true for HIV, and hence, it is often unknown which drug is best to use or to develop against an individual HIV strain. In this work we applied ‘proteochemometric’ modeling of HIV Non-Nucleoside Reverse Transcriptase (NNRTI) inhibitors to support preclinical development by predicting compound performance on multiple mutants in the lead selection stage. Proteochemometric models are based on both small molecule and target properties and can thus capture multi-target activity relationships simultaneously, the targets in this case being a set of 14 HIV Reverse Transcriptase (RT) mutants. We validated our model by experimentally confirming model predictions for 317 untested compound – mutant pairs, with a prediction error comparable with assay variability (RMSE 0.62). Furthermore, dependent on the similarity of a new mutant to the training set, we could predict with high accuracy which compound will be most effective on a sequence with a previously unknown genotype. Hence, our models allow the evaluation of compound performance on untested sequences and the selection of the most promising leads for further preclinical research. The modeling concept is likely to be applicable also to other target families with genetic variability like other viruses or bacteria, or with similar orthologs like GPCRs
Green infrastructure can promote plant functional connectivity in a grassland species around fragmented semi‐natural grasslands in NW‐Europe
Species may benefit from green infrastructure, i.e. the network of natural and anthropogenic habitat remnants in human-dominated landscapes, if it helps isolated populations in remaining habitat patches to be functionally connected. The importance of green infrastructure is therefore increasingly emphasized in conservation policy to counter biodiversity loss. However, there is limited evidence, particularly in plants, that green infrastructure promotes functional connectivity, i.e. supports the colonization of habitat patches across a landscape. We applied landscape genetics to test whether the green infrastructure supports structural and functional connectivity in the grassland perennial Galium verum, in 35 landscapes in Belgium, Germany and Sweden. We used multivariate genetic clustering techniques, nestedness analyses and conditional inference trees to examine landscape-scale patterns in genetic diversity and structure of plant populations in the green infrastructure surrounding semi-natural grasslands. Inferred functional connectivity explained genetic variation better than structural connectivity, yielding positive effects on genetic variation. The road verge network, a major structural component of the green infrastructure and its functional connectivity, most effectively explained genetic diversity and composition in G. verum. Galium verum ramets occupying the surrounding landscape proved to be genetic subsets of focal grassland populations, shaping a nested landscape population genetic structure with focal grasslands, particularly ancient ones, harbouring unique genetic diversity. This nested pattern weakened as road network density increased, suggesting road verge networks enable high landscape occupancy by increased habitat availability and facilitates gene flow into the surrounding landscape. Our study proposes that green infrastructure can promote functional connectivity, providing that a plant species can survive outside of core habitat patches. As this often excludes habitat specialist species, conservation practice and policy should primarily focus on ancient, managed semi-natural grasslands. These grasslands both harbour unique genetic diversity and act as primary gene and propagule sources for the surrounding landscape, highlighting their conservation value
Study protocol for a randomized controlled trial : prophylactic swallowing exercises in head-and-neck cancer patients treated with (chemo)radiotherapy (PRESTO trial)
Background: Dysphagia is a common and serious complication after (chemo)radiotherapy (CRT) for head-and-neck cancer (HNC) patients. Prophylactic swallowing exercises (PSE) can have a significantly positive effect on post-treatment swallowing function. However, low adherence rates are a key issue in undermining this positive effect. This current randomized trial will investigate the effect of adherence-improving measures on patients' swallowing function, adherence and quality of life (QOL).
Methods: This ongoing trial will explore the difference in adherence and swallowing-related outcome variables during and after PSE in HNC patients performing the same therapy schedule, receiving different delivery methods. One hundred and fifty patients treated in various hospitals will be divided into three groups. Group 1 performs PSE at home, group 2 practices at home with continuous counseling through an app and group 3 receives face-to-face therapy by a speech and language pathologist. The exercises consist of tongue-strengthening exercises and chin-tuck against resistance with effortful swallow. The Iowa Oral Performance Instrument and the Swallowing Exercise Aid are used for practicing. Patients are evaluated before, during and after treatment by means of strength measurements, swallowing and QOL questionnaires.
Discussion: Since low adherence rates undermine the positive impact of PSE on post-treatment swallowing function, there is need to develop an efficient PSE protocol maximizing adherence rates
Application of Simple Smart Logic for Waterflooding Reservoir Management
A simple smart logic for controlling inflow control valves (ICV) in waterflooding reservoir management is implemented and analyzed, with the final objective of improving the long term financial return of a petroleum reservoir.
Such a control is based in a reactive simple logic that responds to the watercut measured in the ICV. Basically, when the watercut increases, the ICV is set to close proportionally. For comparison purposes, four strategies are presented: base case scenario with conventional control, the best completion configuration found by trial-and-error, the reactive control, and a deterministic optimal control based on Nonlinear Gradient Method with adjoint-gradient formulation is shown for comparison purposes. Finally, all four strategies are tested again in different reservoir realizations in order to mimic the geological uncertainties.
Two different synthetic reservoir models were studied. First, a simple cube with a five-spot well configuration, in which the permeability field has a horizontal pattern defined by lognormal distributions. The second model is a benchmark proposed by the Dutch university, TU delft, with 101 channelized permeability fields representing river patterns.
For the first model, no significant relative gain is found neither in the variable control nor in the optimal control. Manly because of the high homogeneity of the reservoir models. Therefore, no intelligent completion is recommended. On the other hand, for the second and more complex case, the results indicate an expressive relative gain in the use of simple reactive logic. Besides, this type of control achieves results nearly as good as the optimal control.
The test in different realizations, however, shows that reservoir characterization is still a key part of any attempt to improve production. Although the variable reactive control is semi-independent, with action being taken based on measurements, some parameters need a priori model to be tuned
Once-daily simeprevir (TMC435) with pegylated interferon and ribavirin in treatment-naïve genotype 1 hepatitis C: The randomized PILLAR study
The phase IIb, double-blind, placebo-controlled PILLAR trial investigated the efficacy and safety of two different simeprevir (SMV) doses administered once-daily (QD) with pegylated interferon (Peg-IFN)-α-2a and ribavirin (RBV) in treatment-naïve patients with HCV genotype 1 infection. Patients were randomized to one of five treatments: SMV (75 or 150 mg QD) for 12 or 24 weeks or placebo, plus Peg-IFN and RBV. Patients in the SMV arms stopped all treatment at week 24 if response-guided therapy (RGT) criteria were met; patients not meeting RGT continued with Peg-IFN and RBV until week 48, as did patients in the placebo control group. Sustained virologic response (SVR) rates measured 24 weeks after the planned end of treatment (SVR24) were 74.7%-86.1% in the SMV groups versus 64.9% in the control group (P < 0.05 for all comparisons [SMV versus placebo], except SMV 75 mg for 24 weeks). Rapid virologic response (HCV RNA <25 IU/mL undetectable at week 4) was achieved by 68.0%-75.6% of SMV-treated and 5.2% of placebo control patients. According to RGT criteria, 79.2%-86.1% of SMV-treated patients completed treatment by week 24; 85.2%-95.6% of these subsequently achieved SVR24. The adverse event profile was generally similar across the SMV and placebo control groups, with the exception of mild reversible hyperbilirubinemia, without serum aminotransferase abnormalities, associated with higher doses of SMV
Study protocol for a randomized controlled trial: tongue strengthening exercises in head and neck cancer patients, does exercise load matter?
Water-Based Heating/Cooling in Residential Buildings: Towards Optimal Heat Emission/Absorption Elements (Water-gebaseerde verwarming/koeling in residentiële gebouwen: naar optimale warmte emissie-/absorptie-elementen)
This dissertation describes the development of a new method for si mulating water-based heating/cooling installations in residential buildi ngs and demonstrates how such method could be used to determine optimal heat emission/absorption elements for residential buildings. The reason to develop this new simulation method was to define optimal h eat emission/absorption elements that fulfil the thermal comfort require ments in an energy efficient way. Based on a thorough state-of-the-art s tudy, the thermal comfort requirements for the specific setting of a res idential building have been defined. It is shown that 3 different zones can be distinguished; the bathroom, the bedroom and the other zones. Eac h of these zones requires different temperature settings in order to sat isfy the thermal sensation of its occupants. The width of the band of ac ceptable temperatures around this neutral temperature was determined to be 5 K, asymmetrically distributed around the neutral value. Besides this steady state thermal comfort, a potential optimal heat emit ter/absorber should further cause limited indoor temperature fluctuation s. These dynamic thermal conditions are difficult to incorporate in buil ding energy simulation software due to their dependency on the simulatio n timestep. However, by simulating with a fixed small timestep when opti mising different heat emission/absorption elements, a too high cycle fre quency of the indoor temperature can be penalised. The thermal comfort requirements define the boundary conditions a heatin g/cooling installation should fulfil. An algorithm to verify the thermal comfort requirements and the structure to model heating/cooling install ations have been embedded in an existing building energy simulation soft ware to correctly account for the building-installation interactions. Th e building simulation code used is ESP-r. The implicit plant modelling i mplementation is mainly embedded within the ESP-r s zone/building contro l level. It contains a heat emission/absorption model with idealised and more realistic controls, a structure for a distribution level and a pro duction device model with different controls and different efficiency ca lculation routines. The model for the heat emission/absorption element is based on a formula , commonly encountered in building simulation, to represent different ty pes of water-based heat emission elements. Through an extended theoretic al analysis, improvements to this formula have been proposed. This model requires a limited amount of characterising parameters. To de termine the optimal value for each of these parameters, the building sim ulation code ESP-r, extended with the implic it modelling approach, has been coupled with the optimisation tool GenOp t. This coupling allows determining the optimal heat emitter/absorber el ement for a given building model in a specific setting. Through various examples, the possibilities and limitations of this generic methodology have been demonstrated.nrpages: 315status: publishe
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