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Hormones, the postmen in the plant. Hormones are key to dozens of growth and development processes.
No full textStrategies to compensate for undesired gritty sensations in foods
No full textThis study investigated whether the addition of macroparticles or fat can be used to compensate for negative texture sensations in quark. Cellulose beads were added as model microparticles (1.5% w/w; average size: 263 µm) to quark (0% fat) to induce unpleasant gritty sensations. The addition of microparticles to quark significantly increased grittiness and dryness, while creaminess and liking decreased. Three strategies were explored to reduce the impact of unpleasant gritty sensations on consumer perception: two strategies involved the addition of macroparticles (granola or peach gel pieces); the third one consisted of increasing the fat content of the quark (4.4 and 8.8% w/w). For all three strategies, grittiness caused by microparticles did not significantly decrease when macroparticles or fat were present. Addition of peach gel pieces to quark with microparticles did not increase liking. When granola pieces were added to quark containing microparticles, liking increased significantly despite that grittiness was still perceived. Temporal Dominance of Sensations (TDS) revealed that addition of granola pieces caused prolonged dominance of positive, crunchy sensations and minimized dominance of negative, gritty sensations. The addition of fat did not lead to a significant increase in liking of quark, although when a medium amount of fat was added (4.4%), it also did not decrease liking significantly. This was probably due to an effective hedonic compensation triggered by more positive sensations (i.e. sweetness). We conclude that addition of crunchy granola pieces or fat can be used as strategies to shift and increase dominance of positive and liked attributes, leading to an increase of overall liking, although negative sensations (grittiness) caused by microparticles are still perceived. This approach could be used to compensate for undesired texture sensations in different types of foods, such as high protein foods.</p
Mapping wetland characteristics using temporally dense Sentinel-1 and Sentinel-2 data: A case study in the St. Lucia wetlands, South Africa
No full textWetlands have been determined as one of the most valuable ecosystems on Earth and are currently being lost at alarming rates. Large-scale monitoring of wetlands is of high importance, but also challenging. The Sentinel-1 and -2 satellite missions for the first time provide radar and optical data at high spatial and temporal detail, and with this a unique opportunity for more accurate wetland mapping from space arises. Recent studies already used Sentinel-1 and -2 data to map specific wetland types or characteristics, but for comprehensive wetland characterisations the potential of the data has not been researched yet. The aim of our research was to study the use of the high-resolution and temporally dense Sentinel-1 and -2 data for wetland mapping in multiple levels of characterisation. The use of the data was assessed by applying Random Forests for multiple classification levels including general wetland delineation, wetland vegetation types and surface water dynamics. The results for the St. Lucia wetlands in South Africa showed that combining Sentinel-1 and -2 led to significantly higher classification accuracies than for using the systems separately. Accuracies were relatively poor for classifications in high-vegetated wetlands, as subcanopy flooding could not be detected with Sentinel-1’s C-band sensors operating in VV/VH mode. When excluding high-vegetated areas, overall accuracies were reached of 88.5% for general wetland delineation, 90.7% for mapping wetland vegetation types and 87.1% for mapping surface water dynamics. Sentinel-2 was particularly of value for general wetland delineation, while Sentinel-1 showed more value for mapping wetland vegetation types. Overlaid maps of all classification levels obtained overall accuracies of 69.1% and 76.4% for classifying ten and seven wetland classes respectively
Use of iron oxide nanoparticles for immobilizing phosphorus in-situ : Increase in soil reactive surface area and effect on soluble phosphorus
No full textPhosphorus (P) immobilization has potential for reducing diffuse P losses from legacy P soils to surface waters and for regenerating low-nutrient ecosystems with a high plant species richness. Here, P immobilization with iron oxide sludge application was investigated in a field trial on a noncalcareous sandy soil. The sludge applied is a water treatment residual produced from raw groundwater by Fe(II) oxidation. Siliceous ferrihydrite (Fh) is the major Fe oxide type in the sludge. The reactive surface area assessed with an adapted probe ion method is 211–304 m2 g−1 for the Fe oxides in the sludge, equivalent to a spherical particle diameter of ~6–8 nm. This size is much larger than the primary Fh particle size (~2 nm) observed with transmission electron microscopy. This can be attributed to aggregation initiated by silicate adsorption. The surface area of the indigenous metal oxide particles in the field trial soils is much higher (~1100 m2 g−1), pointing to the presence of ultra-small oxide particles (2.3 ± 0.4 nm). The initial soil surface area was 5.4 m2 g−1 and increased linearly with sludge application up to a maximum of 12.9 m2 g−1 when 27 g Fe oxides per kg soil was added. In case of a lower addition (~10–15 g Fe oxides per kg soil), a 10-fold reduction in the phosphate (P-PO4) concentration in 0.01 M CaCl2 soil extracts to 0.3 µM was possible. The adapted probe ion method is a valuable tool for quantifying changes in the soil surface area when amending soil with Fe oxide-containing materials. This information is important for mechanistically predicting the reduction in the P-PO4 solubility when such materials are used for immobilizing P in legacy P soils with a low P-PO4 adsorption capacity but with a high surface loading.</p
Not-so-SMART: Why new platform and surveillance technologies are bad news for science and understanding
No full textThis short paper critically engages with new technologies for data processing related to research outputs, connections and management. Such technologies are generally heralded as making research and publishing more efficient, enabling better connections between researchers and bringing disparate forms of research data together for better research and output management. Based on the examples of Elsevier's Pure and Fingerprint technologies, I argue that in reality the effects of these new technologies and the surveillance platforms they are based on, will be precisely the opposite: they degrade scientific understanding and relations by reducing them to superficial numbers, clicks and hits; they will lead to increased anxiety and stress among academic staff; and they open up the possibilities for new types of panopticon academic governance. The paper concludes by exploring an alternative based on decentralized diversity in research(er) representation.</p
The Chick Diffusion: How Newspapers Fail to Meet Normative Expectations Regarding Their Democratic Role in Public Debate
No full textMedia scholarship has commonly regarded newspapers as an essential element of strong democratic societies: a forum that structures public debate, providing engaged citizens with coherent frameworks to identify, interpret and tackle complex issues. Despite general agreement on the merits of this goal, there is little empirical evidence suggesting it approximates the democratic role historically played by newspapers. We examined three decades of newspaper coverage of chicken meat production in the UK to find evidence relevant to the normative expectations of the democratic role of newspapers as forum for public debate, by means of a two-stage framing analysis of 766 relevant articles from seven outlets. We found mutually disconnected episodic coverage of specific issues whose aggregate effect is consistent with the diffusion rather than the structuring of public debate. Newspapers here afforded polemic rather than the systemic contestation expected. The polemic contestation we found, with diffusion of public debate as an emergent political effect, troubles the assumptions subsequent to which it is possible to argue for the democratic role of newspapers
Consequences of negative energy balance on follicular development and oocyte quality in primiparous sows
No full textMetabolic demands of modern hybrid sows have increased over the years, which increases the chance that sows enter a substantial negative energy balance (NEB) during lactation. This NEB can influence the development of follicles and oocytes that will give rise to the next litter. To study effects of a lactational NEB on follicular development, we used 36 primiparous sows of which 18 were subjected to feed restriction (3.25 kg/day) and 18 were full-fed (6.5 kg/day) during the last 2 weeks of a 24.1 ± 0.3 day lactation. Feed restriction resulted in a 70% larger lactational body weight loss and 76% higher longissimus dorsi depth loss, but similar amounts of backfat loss compared to the full fed sows. These changes were accompanied by lower plasma insulin-like growth factor 1 (IGF1) and higher plasma creatinine levels in the restricted sows from the last week of lactation onward. Ovaries were collected 48 h after weaning. Restricted sows had a lower average size of the 15 largest follicles (−26%) and cumulus–oocyte complexes showed less expansion after 22 h in vitro maturation (−26%). Less zygotes of restricted sows reached the metaphase stage 24 h after in vitro fertilization and showed a higher incidence of polyspermy (+89%). This shows that feed restriction had severe consequences on oocyte developmental competence. Follicular fluid of restricted sows had lower IGF1 (−56%) and steroid levels (e.g., β-estradiol, progestins, and androgens), which indicated that follicles of restricted sows were less competent to produce steroids and growth factors needed for oocytes to obtain full developmental competence
Rescue of tomato spotted wilt virus entirely fromcomplementary DNA clones
No full textNegative-stranded/ambisense RNA viruses (NSVs) include not only dangerous pathogens of medical importance but also serious plant pathogens of agronomic importance. Tomato spotted wilt virus (TSWV) is one of the most important plant NSVs, infecting more than 1,000 plant species, and poses major threats to global food security. The segmented negative-stranded/ambisense RNA genomes of TSWV, however, have been a major obstacle to molecular genetic manipulation. In this study, we report the complete recovery of infectious TSWV entirely from complementary DNA (cDNA) clones. First, a replication- and transcription-competent minigenome replication system was established based on 35S-driven constructs of the S(−)-genomic (g) or S(+)-antigenomic (ag) RNA template, flanked by the 5′ hammerhead and 3′ ribozyme sequence of hepatitis delta virus, a nucleocapsid (N) protein gene and codon-optimized viral RNA-dependent RNA polymerase (RdRp) gene. Next, a movement-competent minigenome replication system was developed based on M(−)-gRNA, which was able to complement cell-to-cell and systemic movement of reconstituted ribonucleoprotein complexes (RNPs) of S RNA replicon. Finally, infectious TSWV and derivatives carrying eGFP reporters were rescued in planta via simultaneous expression of full-length cDNA constructs coding for S(+)-agRNA, M(−)-gRNA, and L(+)-agRNA in which the glycoprotein gene sequence of M(−)-gRNA was optimized. Viral rescue occurred with the addition of various RNAi suppressors including P19, HcPro, and γb, but TSWV NSs interfered with the rescue of genomic RNA. This reverse genetics system for TSWV now allows detailed molecular genetic analysis of all aspects of viral infection cycle and pathogenicity
Nitrogen deposition is the most important environmental driver of growth of pure, even-aged and managed European forests
No full textChanging environmental conditions may substantially interact with site quality and forest stand characteristics, and impact forest growth and carbon sequestration. Understanding the impact of the various drivers of forest growth is therefore critical to predict how forest ecosystems can respond to climate change. We conducted a continental-scale analysis of recent (1995–2010) forest volume increment data (ΔVol, m3 ha−1 yr−1), obtained from ca. 100,000 coniferous and broadleaved trees in 442 even-aged, single-species stands across 23 European countries. We used multivariate statistical approaches, such as mixed effects models and structural equation modelling to investigate how European forest growth respond to changes in 11 predictors, including stand characteristics, climate conditions, air and site quality, as well as their interactions. We found that, despite the large environmental gradients encompassed by the forests examined, stand density and age were key drivers of forest growth. We further detected a positive, in some cases non-linear effect of N deposition, most pronounced for beech forests, with a tipping point at ca. 30 kg N ha−1 yr−1. With the exception of a consistent temperature signal on Norway spruce, climate-related predictors and ground-level ozone showed much less generalized relationships with ΔVol. Our results show that, together with the driving forces exerted by stand density and age, N deposition is at least as important as climate to modulate forest growth at continental scale in Europe, with a potential negative effect at sites with high N deposition.</p
Peripheral blood mononuclear cells as a source of cold exposure biomarkers
No full textMale ferrets, aged 3 months, were divided into two group: one group remained at 22 degrees Celsius, while the other group was acclimatized to 4 degrees Celsius for one week. After sacrification, inguinal and periaortic white adipose tissues were dissected, and peripheral blood mononuclear cells (PBMC) were isolated. The three tissues are used for RNA isolation and subsequent global gene expression profiling using custom Agilent ferret-specific 2x400K microarrays. Data analysis indicated that the cold exposure induce a clear gene expression response of some genes in the inguinal and periaortic white adipose tissue as in PBMC. These genes could be defined as a biomakers of the effect of cold exposure in these cells