Techno-economic heat transfer optimization of large scale latent heat energy storage systems in solar thermal power plants

Concentrated solar power plants with integrated storage systems are key technologies for sustainable energy supply systems and reduced anthropogenic CO2-emissions. Developing technologies include direct steam generation in parabolic trough systems, which offer benefits due to higher steam temperatures and, thus, higher electrical efficiencies. However, no large scale energy storage technology is available yet. A promising option is a combined system consisting of a state-of-the art sensible molten salt storage system and a high temperature latent heat thermal energy storage system (LHTESS). This paper discusses the systematic development and optimization of heat transfer structures in LHTESS from a technological and economic point of view. Two evaluation parameters are developed in order to minimize the specific investment costs. First, the specific product costs determine the optimum equipment of the latent heat storage module, i.e. the finned tube. The second parameter reflects the interacting behavior of the LHTESS and the steam turbine during discharge. This behavior is described with a simplified power block model that couples both components

In vivo aroma release and dynamic sensory perception of composite foods

8openInternationalInternational coauthor/editorCondiments such as spreads, dressings, or sauces are usually consumed together with carrier foods such as breads or vegetables. Dynamic interactions between condiments and carriers occur during consumption, which can influence aroma release and perception. This study investigated in vivo aroma release (PTR-MS) and dynamic sensory perception (time–intensity) of mayonnaises spiked with lemon aroma (limonene, citral). Mayonnaises were assessed without and with carrier foods (bread, potato). When different mayonnaises were consumed and assessed alone, aroma release and intensity perception were positively correlated. Interestingly, when mayonnaises were combined with carriers, aroma release and perception were no longer positively correlated. Addition of carriers increased release of limonene and citral into the nasal cavity during consumption but decreased perceived aroma intensity of condiments. The increase in aroma release induced by the carriers can be explained by differences in oral processing behaviors and by the increased surface area of mayonnaise-carrier combinations. Carrier addition is likely to modulate aroma perception of composite foods by cross-modal texture–aroma interactions. This work demonstrates that not only physicochemical characteristics of foods but also cross-modal interactions play a role in influencing flavor perception of composite foods.openvan Eck, Arianne; Pedrotti, Michele; Brouwer, Rutger; Supapong, Arpavee; Fogliano, Vincenzo; Scholten, Elke; Biasioli, Franco; Stieger, Markusvan Eck, A.; Pedrotti, M.; Brouwer, R.; Supapong, A.; Fogliano, V.; Scholten, E.; Biasioli, F.; Stieger, M

Oral processing behavior and dynamic sensory perception of composite foods : Toppings assist saliva in bolus formation

Composite foods consist of combinations of single foods, such as bread with toppings. Single foods can differ considerably in their mechanical and sensory properties. This study aimed to investigate the effect of toppings on oral processing behavior and dynamic sensory perception of carrier foods when consumed as composite foods. Two carriers (bread, crackers) and three toppings (firm cheese, cheese spread, mayonnaise) were selected and six carrier-topping combinations were prepared. Mastication behavior, bolus properties (33, 66 and 100% of total mastication time) and dynamic sensory perception were determined for single carriers and all carrier-topping combinations. Both carriers with cheese spread and mayonnaise were chewed shorter and with fewer chews than single bread and crackers, although twice the mass of food was consumed. These toppings contributed to a faster bolus formation by providing moisture, so that less saliva was incorporated into the bolus during mastication. As a result of the moisture incorporation, carrier boli with toppings were softened and perceived less firm and less dry than carrier boli alone. The largest effects of toppings on oral processing behavior and perception were found for liquid-like mayonnaise, and these effects were more pronounced in dry crackers than in moist bread. We conclude that toppings assist saliva in bolus formation of carriers. Carriers drive oral processing behavior and texture perception whereas toppings drive overall flavor perception. This knowledge contributes to food design tailored for specific consumer segments and future personalized nutrition.</p

Re-producing public space: the changing everyday production of outdoor retail markets

In 2020, nation states across Europe restricted access to, and use of, public space to prevent the spread of COVID-19. As almost all public spaces in Europe were consequently affected by restrictive measures, so too did outdoor retail markets drastically change. Some had to close down completely, whereas others operated under the sway of severe limitations for traders and customers. By re-engaging with the work of the late Michael Sorkin, it could be argued that the effects of COVID-19 add another dimension to the “end” or “death” of public space. In this paper, we shift attention to the tactics and strategies of one category of public figures behind the everyday production of markets, the traders, to show that markets in Spain, the United Kingdom, Switzerland and the Netherlands did not simply stop functioning as public spaces. Rather, they took on different forms that extended spatially beyond their physical boundaries. These transformations allowed for the continuation of the social and political dimensions of public space

Assignment of chromosomal locations for unassigned SNPs/scaffolds based on pair-wise linkage disequilibrium estimates

<p>Abstract</p> <p>Background</p> <p>Recent developments of high-density SNP chips across a number of species require accurate genetic maps. Despite rapid advances in genome sequence assembly and availability of a number of tools for creating genetic maps, the exact genome location for a number of SNPs from these SNP chips still remains unknown. We have developed a locus ordering procedure based on linkage disequilibrium (LODE) which provides estimation of the chromosomal positions of unaligned SNPs and scaffolds. It also provides an alternative means for verification of genetic maps. We exemplified LODE in cattle.</p> <p>Results</p> <p>The utility of the LODE procedure was demonstrated using data from 1,943 bulls genotyped for 73,569 SNPs across three different SNP chips. First, the utility of the procedure was tested by analysing the masked positions of 1,500 randomly-chosen SNPs with known locations (50 from each chromosome), representing three classes of minor allele frequencies (MAF), namely >0.05, 0.01<MAF ≤ 0.05 and 0.001<MAF ≤ 0.01. The efficiency (percentage of masked SNPs that could be assigned a location) was 96.7%, 30.6% and 2.0%; with an accuracy (the percentage of SNPs assigned correctly) of 99.9%, 98.9% and 33.3% in the three classes of MAF, respectively. The average precision for placement of the SNPs was 914, 3,137 and 6,853 kb, respectively. Secondly, 4,688 of 5,314 SNPs unpositioned in the Btau4.0 assembly were positioned using the LODE procedure. Based on these results, the positions of 485 unordered scaffolds were determined. The procedure was also used to validate the genome positions of 53,068 SNPs placed on Btau4.0 bovine assembly, resulting in identification of problem areas in the assembly. Finally, the accuracy of the LODE procedure was independently validated by comparative mapping on the hg18 human assembly.</p> <p>Conclusion</p> <p>The LODE procedure described in this study is an efficient and accurate method for positioning SNPs (MAF>0.05), for validating and checking the quality of a genome assembly, and offers a means for positioning of unordered scaffolds containing SNPs. The LODE procedure will be helpful in refining genome sequence assemblies, especially those being created from next-generation sequencing where high-throughput SNP discovery and genotyping platforms are integrated components of genome analysis.</p

CpG-Methylation Regulates a Class of Epstein-Barr Virus Promoters

DNA methylation is the major modification of eukaryotic genomes and plays an essential role in mammalian gene regulation. In general, cytosine-phosphatidyl-guanosine (CpG)-methylated promoters are transcriptionally repressed and nuclear proteins such as MECP2, MBD1, MBD2, and MBD4 bind CpG-methylated DNA and contribute to epigenetic silencing. Methylation of viral DNA also regulates gene expression of Epstein-Barr virus (EBV), which is a model of herpes virus latency. In latently infected human B cells, the viral DNA is CpG-methylated, the majority of viral genes is repressed and virus synthesis is therefore abrogated. EBV's BZLF1 encodes a transcription factor of the AP-1 family (Zta) and is the master gene to overcome viral gene repression. In a genome-wide screen, we now identify and characterize those viral genes, which Zta regulates. Among them are genes essential for EBV's lytic phase, which paradoxically depend on strictly CpG-methylated promoters for their Zta-induced expression. We identified novel DNA recognition motifs, termed meZRE (methyl-Zta-responsive element), which Zta selectively binds in order to ‘read’ DNA in a methylation- and sequence-dependent manner unlike any other known protein. Zta is a homodimer but its binding characteristics to meZREs suggest a sequential, non-palindromic and bipartite DNA recognition element, which confers superior DNA binding compared to CpG-free ZREs. Our findings indicate that Zta has evolved to transactivate cytosine-methylated, hence repressed, silent promoters as a rule to overcome epigenetic silencing

Natalizumab treatment shows low cumulative probabilities of confirmed disability worsening to EDSS milestones in the long-term setting.

Abstract Background Though the Expanded Disability Status Scale (EDSS) is commonly used to assess disability level in relapsing-remitting multiple sclerosis (RRMS), the criteria defining disability progression are used for patients with a wide range of baseline levels of disability in relatively short-term trials. As a result, not all EDSS changes carry the same weight in terms of future disability, and treatment benefits such as decreased risk of reaching particular disability milestones may not be reliably captured. The objectives of this analysis are to assess the probability of confirmed disability worsening to specific EDSS milestones (i.e., EDSS scores ≥3.0, ≥4.0, or ≥6.0) at 288 weeks in the Tysabri Observational Program (TOP) and to examine the impact of relapses occurring during natalizumab therapy in TOP patients who had received natalizumab for ≥24 months. Methods TOP is an ongoing, open-label, observational, prospective study of patients with RRMS in clinical practice. Enrolled patients were naive to natalizumab at treatment initiation or had received ≤3 doses at the time of enrollment. Intravenous natalizumab (300 mg) infusions were given every 4 weeks, and the EDSS was assessed at baseline and every 24 weeks during treatment. Results Of the 4161 patients enrolled in TOP with follow-up of at least 24 months, 3253 patients with available baseline EDSS scores had continued natalizumab treatment and 908 had discontinued (5.4% due to a reported lack of efficacy and 16.4% for other reasons) at the 24-month time point. Those who discontinued due to lack of efficacy had higher baseline EDSS scores (median 4.5 vs. 3.5), higher on-treatment relapse rates (0.82 vs. 0.23), and higher cumulative probabilities of EDSS worsening (16% vs. 9%) at 24 months than those completing therapy. Among 24-month completers, after approximately 5.5 years of natalizumab treatment, the cumulative probabilities of confirmed EDSS worsening by 1.0 and 2.0 points were 18.5% and 7.9%, respectively (24-week confirmation), and 13.5% and 5.3%, respectively (48-week confirmation). The risks of 24- and 48-week confirmed EDSS worsening were significantly higher in patients with on-treatment relapses than in those without relapses. An analysis of time to specific EDSS milestones showed that the probabilities of 48-week confirmed transition from EDSS scores of 0.0–2.0 to ≥3.0, 2.0–3.0 to ≥4.0, and 4.0–5.0 to ≥6.0 at week 288 in TOP were 11.1%, 11.8%, and 9.5%, respectively, with lower probabilities observed among patients without on-treatment relapses (8.1%, 8.4%, and 5.7%, respectively). Conclusions In TOP patients with a median (range) baseline EDSS score of 3.5 (0.0–9.5) who completed 24 months of natalizumab treatment, the rate of 48-week confirmed disability worsening events was below 15%; after approximately 5.5 years of natalizumab treatment, 86.5% and 94.7% of patients did not have EDSS score increases of ≥1.0 or ≥2.0 points, respectively. The presence of relapses was associated with higher rates of overall disability worsening. These results were confirmed by assessing transition to EDSS milestones. Lower rates of overall 48-week confirmed EDSS worsening and of transitioning from EDSS score 4.0–5.0 to ≥6.0 in the absence of relapses suggest that relapses remain a significant driver of disability worsening and that on-treatment relapses in natalizumab-treated patients are of prognostic importance

Some Aspects of Parabolic Trough Field Operation with Oil as a Heat Transfer Fluid

Solar power plants of the SEGS-type gained enormous attention within the last years. A number of plants are already under construction or even close to grid operation. The bases for these developments are the experiences gained with the American plants in the past 20 years. This paper concentrates on two aspects concerning the operation of the plant which are, according to the authors experience, often not considered in the design phase of a new plant although their impact on the performance or component requirements of the plant is quite significant. The aspect of defocusing at over-load is analyzed by energy balances. The second field of oil temperature controllability is studied using a dynamic simulation tool