•Morphology and different structural levels of V-amylose complexes were evaluated.•Complexes displayed high dissociation temperature and IIb-type polymorphism.•Crystals tended to aggregate and form ...agglomerates of various sizes.•Complexes showed an aggregated strand structure interwoven with GMS.•Self-association tendency of GMS increased at high GMS concentrations.
Morphology and different structural features of V-amylose complexes prepared with different concentrations (1%, 2%, 3%) of glycerol monostearate (GMS) and normal maize (NMS), waxy maize (WMS), and high amylose maize (HAMS) starches were evaluated using X-ray diffraction, differential scanning calorimetry, scanning electronic microscopy (SEM), atomic force microscopy (AFM), and transmission electronic microscopy (TEM). There was inclusion complex formation between all starches and GMS regardless of emulsifier concentration, with exception of WMS-2%GMS and WMS-3%GMS samples. All of the inclusion complexes displayed a V-type crystalline pattern and endothermic dissociation peaks between 115 and 120°C. They also displayed faceted crystalline structures with a tendency of the crystals to aggregate and form agglomerates of various sizes. TEM images of the complexes showed an aggregated strand structure interwoven with the GMS. Emulsifier and amylose quantities directly influenced complex formation. At high GMS concentrations, there was higher tendency of emulsifier to self-associate rather than form complexes with amylose.
‘Land grab’ has become a catch‐all phrase to refer to the current explosion of (trans)national commercial land transactions mainly revolving around the production and export of food, animal feed, ...biofuels, timber and minerals. Two key dimensions of the current land grab – namely, the politics of changes in land use and property relations change (and the links between them) – are not sufficiently explored in the current literature. We attempt to address this gap by offering a preliminary analysis through an analytical approach that suggests some typologies as a step towards a fuller and better understanding of the politics of global land grabbing.
SARS-CoV-2 infection represents a global health problem that has affected millions of people. The fine host immune response and its association with the disease course have not yet been fully ...elucidated. Consequently, we analyze circulating B cell subsets and their possible relationship with COVID-19 features and severity.
Using a multiparametric flow cytometric approach, we determined B cell subsets frequencies from 52 COVID-19 patients, grouped them by hierarchical cluster analysis, and correlated their values with clinical data.
The frequency of CD19
B cells is increased in severe COVID-19 compared to mild cases. Specific subset frequencies such as transitional B cell subsets increase in mild/moderate cases but decrease with the severity of the disease. Memory B compartment decreased in severe and critical cases, and antibody-secreting cells are increased according to the severity of the disease. Other non-typical subsets such as double-negative B cells also showed significant changes according to disease severity. Globally, these differences allow us to identify severity-associated patient clusters with specific altered subsets. Finally, respiratory parameters, biomarkers of inflammation, and clinical scores exhibited correlations with some of these subpopulations.
The severity of COVID-19 is accompanied by changes in the B cell subpopulations, either immature or terminally differentiated. Furthermore, the existing relationship of B cell subset frequencies with clinical and laboratory parameters suggest that these lymphocytes could serve as potential biomarkers and even active participants in the adaptive antiviral response mounted against SARS-CoV-2.
Spectrally unentangled biphotons with high single-spatiotemporal-mode purity are highly desirable for many quantum information processing tasks. We generate biphotons with an inferred heralded-state ...spectral purity of 99%, the highest to date without any spectral filtering, by pulsed spontaneous parametric downconversion in a custom-fabricated periodically-poled KTiOPO
crystal under extended Gaussian phase-matching conditions. To efficiently characterize the joint spectral intensity of the generated biphotons at high spectral resolution, we employ a commercially available dispersion compensation module (DCM) with a dispersion equivalent to 100 km of standard optical fiber and with an insertion loss of only 2.8 dB. Compared with the typical method of using two temperature-stabilized equal-length fibers that incurs an insertion loss of 20 dB per fiber, the DCM approach achieves high spectral resolution in a much shorter measurement time. Because the dispersion amount and center wavelengths of DCMs can be easily customized, spectral characterization in a wide range of quantum photonic applications should benefit significantly from this technique.
We present an interdisciplinary review of the observed and projected variations in atmospheric and oceanic circulation within the southwestern South Atlantic focused on basin-scale processes driven ...by climate change, and their potential impact on the regional fisheries. The observed patterns of atmospheric circulation anomalies are consistent with anthropogenic climate change. There is strong scientific evidence suggesting that the Brazil Current is intensifying and shifting southwards during the past decades in response to changes in near-surface wind patterns, leading to intense ocean warming along the path of the Brazil Current, the South Brazil Bight, and in the Río de la Plata. These changes are presumably responsible for the poleward shift of commercially important pelagic species in the region and the long-term shift from cold-water to warm-water species in industrial fisheries of Uruguay. Scientific and traditional knowledge shows that climate change is also affecting small-scale fisheries. Long-term records suggest that mass mortalities decimated harvested clam populations along coastal ecosystems of the region, leading to prolonged shellfishery closures. More frequent and intense harmful algal blooms together with unfavorable environmental conditions driven by climate change stressors affect coastal shellfisheries, impact economic revenues, and damage the livelihood of local communities. We identify future modelling needs to reduce uncertainty in the expected effects of climate change on marine fisheries. However, the paucity of fisheries data prevents a more effective assessment of the impact of climate change on fisheries and hampers the ability of governments and communities to adapt to these changes.
•First excursion probability is estimated taking advantage of linearity.•Simulation is carried out by means of Directional Importance Sampling.•Small failure probabilities can be estimated with a ...reduced number of samples.•Simulation approach applicable to both small and large scale structural models.
This contribution addresses the estimation of first excursion probabilities of linear structural systems subject to stochastic Gaussian loading by means of simulation. This probability is estimated by combining existing knowledge on the geometry of the associated failure domain with Directional Importance Sampling. In this way, the space associated with the stochastic loading is explored by generating some random directions according to a prescribed importance sampling distribution; then, each random direction is analyzed taking advantage of the linearity of the response with respect to the stochastic loading. Such an approach allows estimating small failure probabilities with high accuracy and precision while requiring a reduced number of samples. The application of Directional Importance Sampling is illustrated by means of a series of examples, indicating that failure probabilities in the order of 10-3 or less can be estimated reliably with a reduced number of samples, even in problems comprising involved structural models.
The distribution patterns of fish early life stages are critical to recruitment success and closely related to major oceanographic circulation patterns. We explored the spatiotemporal distribution of ...early life stages of Fuegian sprat Sprattus fuegensis , a key trophic species in the Southwestern Atlantic Ocean (SWAO), in a complex oceanographic setting. Samples were collected during austral spring, summer, and autumn, from 2014 to 2017, across areas with distinct biophysical properties between Tierra del Fuego (TDF) and the marine protected area ‘Namuncurá’ at Burdwood Bank (BB) (ca. 54°S). Results revealed significant seasonal fluctuations in abundance, distribution, and ontogenetic composition across habitats. High egg and early larval abundances at Isla de los Estados (IE) suggest it is an additional spawning ground to those previously identified at TDF and BB. However, only the latter appear to be suitable nursery areas. Particle-tracking simulations based on egg abundance and spawning dates were conducted for the first time using results from a high-resolution hydrodynamic model. Particle transport provides evidence of connectivity between IE and neighbouring areas—enhanced when horizontal diffusivity is incorporated into the model—but not between TDF and BB. Simulated distributions closely resembled empirical patterns from this and other studies, allowing the integration of empirical and modelled data to schematize the species’ dispersal pathways in the study area. These results offer new insights into distribution and connectivity patterns among spawning grounds and highlight the potential use of hydrodynamic models for future assessments of Fuegian sprat and other planktonic species’ dispersal and recruitment in the SWAO.
Abstract
Non-line-of-sight (NLOS) imaging is a rapidly growing field seeking to form images of objects outside the field of view, with potential applications in autonomous navigation, reconnaissance, ...and even medical imaging. The critical challenge of NLOS imaging is that diffuse reflections scatter light in all directions, resulting in weak signals and a loss of directional information. To address this problem, we propose a method for seeing around corners that derives angular resolution from vertical edges and longitudinal resolution from the temporal response to a pulsed light source. We introduce an acquisition strategy, scene response model, and reconstruction algorithm that enable the formation of 2.5-dimensional representations—a plan view plus heights—and a 180
∘
field of view for large-scale scenes. Our experiments demonstrate accurate reconstructions of hidden rooms up to 3 meters in each dimension despite a small scan aperture (1.5-centimeter radius) and only 45 measurement locations.
•Starch isolated from non-edible A. hippocastanum starch is used for preparing of TPS.•A. hippocastanum starch has high swelling power and C-type diffraction pattern.•Glycerol plasticized TPS of A. ...hippocastanum has suitable thermal/mechanical properties.
Starch isolated from non-edible Aesculus hippocastanum seeds was characterized and used for preparing starch-based materials. The apparent amylose content of the isolated starch was 33.1%. The size of starch granules ranged from 0.7 to 35μm, and correlated with the shape of granules (spherical, oval and irregular). The chain length distribution profile of amylopectin showed two peaks, at polymerization degree (DP) of 12 and 41–43. Around 53% of branch unit chains had DP in the range of 11–20. A. hippocastanum starch displayed a typical C-type pattern and the maximum decomposition temperature was 317°C.
Thermoplastic starch (TPS) prepared from A. hippocastanum with glycerol and processed by melt blending exhibited adequate mechanical and thermal properties. In contrast, plasticized TPS with glycerol:malic acid (1:1) showed lower thermal stability and a pasty and sticky behavior, indicating that malic acid accelerates degradation of starch during processing.
The structural and optoelectronic properties of several substituted polyN-9′-heptadecanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole) (PCDTBT) conjugated oligomers have been ...investigated by density functional theory (DFT) and time-dependent density functional theory (TD-DFT). Various electron-withdrawing and electron-donating groups were attached to the 5′ position of the benzothiadiazole unit in the PCDTBT oligomers. HOMO energies (EHOMO), LUMO energies (ELUMO), and the fundamental energy gaps (EGap) were calculated using DFT while the first singlet excited states (EOpt) were calculated using TD-DFT. Results show that the structural properties of the oligomers greatly affect the optoelectronic properties. Results also show that both electron-withdrawing and electron-donating groups are capable of lowering the EGap of PCDTBT. Several properties of substituted PCDTBT, which may affect the solar cell properties, were then calculated and compared with the calculated values for PCDTBT. From the calculated properties, PCDTBT-F showed improvement in the EGap, open-circuit voltage (VOC), and ionization potential (IP), which may lead to solar cells with improved power conversion efficiency (PCE) compared to PCDTBT.
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•Effect of chemical modifications on PCDTBT were studied by DFT and TD-DFT.•Large deviations in Φ and Δr in chemically modified PCDTBT greatly increases EGap and EOpt.•The EGap and EOpt of PCDTBT may be lowered by both electron-withdrawing and electron-donating substituents.•Coplanar thiophene and substituted benzothiadiazole units in PCDTBT derivatives may lead to increased light absorption.•PCDTBT-F may have superior solar cell properties: ISC, VOC, and IP, than PCDTBT.
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