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Iconographic evidence from Egypt suggests that watermelon pulp was consumed there as a dessert by 4,360 BP.
Earlier archaeobotanical evidence comes from seeds from Neolithic settlements in Libya, but whether these were watermelons with sweet pulp or other forms is unknown.
We generated genome sequences from 6,000- and 3,300-year-old seeds from Libya and Sudan, and from worldwide herbarium collections made between 1824 and 2019, and analyzed these data together with resequenced genomes from important germplasm collections for a total of 131 accessions.
Phylogenomic and population-genomic analyses reveal that (1) much of the nuclear genome of both ancient seeds is traceable to West African seed-use "egusi-type" watermelon (Citrullus mucosospermus) rather than domesticated pulp-use watermelon (Citrullus lanatus ssp. vulgaris); (2) the 6,000-year-old watermelon likely had bitter pulp and greenish-white flesh as today found in C. mucosospermus, given alleles in the bitterness regulators ClBT and in the red color marker LYCB; and (3) both ancient genomes showed admixture from C. mucosospermus, C. lanatus ssp. cordophanus, C. lanatus ssp. vulgaris, and even South African Citrullus amarus, and evident introgression between the Libyan seed (UMB-6) and populations of C. lanatus.
An unexpected new insight is that Citrullus appears to have initially been collected or cultivated for its seeds, not its flesh, consistent with seed damage patterns induced by human teeth in the oldest Libyan material.
Detailed microstructural analysis of three basaltic sills of the Little Minch Sill Complex demonstrates that convection leaves a detectable signature in fully solidified bodies. The presence of dense clusters of equant grains of olivine and clinopyroxene in the central parts of sills can only be accounted for if they formed and were enlarged while suspended in convecting magma, with delayed settling to the sill floor.
An associated stratigraphic invariance of plagioclase grain shape is consistent with growth while suspended in convecting magma.
These microstructural indicators demonstrate that convection during solidification was vigorous and long-lived in the 135-m-thick picrodolerite-crinanite unit (PCU) of the composite Shiant Isles Main sill and vigorous and likely short-lived in the PCU of the composite Creagan Iar sill.
In contrast, convection in the Meall Tuath sill was weak and short-lived: plagioclase grain shape in this sill varies with stratigraphic height, indicative of primarily in situ nucleation and growth at the magma-mush interface, while olivine and clinopyroxene were kept suspended in the overlying convecting magma.
The magma in all three sills fractionated during solidification, permitting convection driven by the instability of an upper thermal boundary layer.
The comparative vigour and longevity of convection in the Shiant Isles Main sill and the Creagan Iar sill was due to their emplacement above an earlier, still-hot, intrusion, resulting in highly asymmetric cooling.
Motivation:
Limited data access has hindered the field of precision medicine from exploring its full potential, e.g. concerning machine learning and privacy and data protection rules. Our study evaluates the efficacy of federated Random Forests (FRF) models, focusing particularly on the heterogeneity within and between datasets. We addressed three common challenges: (i) number of parties, (ii) sizes of datasets and (iii) imbalanced phenotypes, evaluated on five biomedical datasets.
Results:
The FRF outperformed the average local models and performed comparably to the data-centralized models trained on the entire data. With an increasing number of models and decreasing dataset size, the performance of local models decreases drastically. The FRF, however, do not decrease significantly. When combining datasets of different sizes, the FRF vastly improve compared to the average local models. We demonstrate that the FRF remain more robust and outperform the local models by analyzing different class-imbalances. Our results support that FRF overcome boundaries of clinical research and enables collaborations across institutes without violating privacy or legal regulations. Clinicians benefit from a vast collection of unbiased data aggregated from different geographic locations, demographics and other varying factors. They can build more generalizable models to make better clinical decisions, which will have relevance, especially for patients in rural areas and rare or geographically uncommon diseases, enabling personalized treatment. In combination with secure multi-party computation, federated learning has the power to revolutionize clinical practice by increasing the accuracy and robustness of healthcare AI and thus paving the way for precision medicine.
Availability and implementation:
The implementation of the federated random forests can be found at https://fea
turecloud.ai/.
We demonstrate that tungsten disulphide (WS2) with thicknesses ranging from monolayer (ML) to several monolayers can be grown on SiO2/Si, Si, and Al2O3 by pulsed direct current-sputtering.
The presence of high quality monolayer and multilayered WS2 on the substrates is confirmed by Raman spectroscopy since the peak separations between the A(1g)-E-2g and A(1g)-2LA vibration modes exhibit a gradual increase depending on the number of layers. X-ray diffraction confirms a textured (001) growth of WS2 films.
The surface roughness measured with atomic force microscopy is between 1.5 and 3 angstrom for the ML films. The chemical composition WSx (x = 2.03 +/- 0.05) was determined from X-ray Photoelectron Spectroscopy.
Transmission electron microscopy was performed on a multilayer film to show the 2D layered structure. A unique method for growing 2D layers directly by sputtering opens up the way for designing 2D materials and batch production of high-uniformity and high-quality (stochiometric, large grain sizes, flatness) WS2 films, which will advance their practical applications in various fields.
Hellweger et al. (Reports, 27 May 2022, pp. 1001) predict that phosphorus limitation will increase concentrations of cyanobacterial toxins in lakes.
However, several molecular, physiological, and ecological mechanisms assumed in their models are poorly supported or contradicted by other studies.
We conclude that their take-home message that phosphorus load reduction will make Lake Erie more toxic is seriously flawed.
Background:
Inflammaging is considered to drive loss of muscle function. Omega-3 fatty acids exhibit anti-inflammatory properties. Therefore, we examined the effects of eight weeks of vibration and home-based resistance exercise combined with a whey-enriched, omega-3-supplemented diet on muscle power, inflammation and muscle biomarkers in community-dwelling old adults.
Methods:
Participants were randomized to either exercise (3x/week, n = 20), exercise + high-protein diet (1.2-1.5 g/kg, n = 20), or exercise + high-protein and omega-3-enriched diet (2.2 g/day, n = 21). Muscle power (watt/m(2)) and chair rise test (CRT) time (s) were assessed via CRT measured with mechanography. Furthermore, leg strength (kg/m(2)) and fasting concentrations of inflammatory (interleukin (IL-) 6, IL-10, high-mobility group box-1 (HMGB-1)) and muscle biomarkers (insulin-like growth factor (IGF-) 1, IGF-binding protein-3, myostatin) were assessed.
Results:
Sixty-one participants (70.6 +/- 4.7 years; 47% men) completed the study. According to generalized linear mixed models, a high-protein diet improved leg strength and CRT time. Only IGF-1 increased with additional omega-3. Sex-specific analyses revealed that muscle power, IL-6, IL-6/IL-10 ratio, and HMGB-1 improved significantly in the male high-protein, omega-3-enriched group only.
Conclusion:
Vibration and home-based resistance exercise combined with a high-protein, omega-3-enriched diet increased muscle power and reduced inflammation in old men, but not in old women. While muscle biomarkers remained unchanged, a high-protein diet combined with exercise improved leg strength and CRT time.
Age-depth relationships are the key elements in paleoenvironmental studies to place proxy measurements into a temporal context.
However, potential influencing factors of the available radiocarbon data and the associated modeling process can cause serious divergences of age-depth relationships from true chronologies, which is particularly challenging for paleolimnological studies in Arctic regions.
This paper provides geoscientists with a tool-assisted approach to compare outputs from age-depth modeling systems and to strengthen the robustness of age-depth relationships.
We primarily focused on the development of age determination data from a data collection of high-latitude lake systems (50 to 90 circle N, 55 sediment cores, and a total of 602 dating points). Our approach used five age-depth modeling systems (Bacon, Bchron, clam, hamstr, Undatable) that we linked through a multi-language Jupyter Notebook called LANDO ("Linked age and depth modeling").
Within LANDO we implemented a pipeline from data integration to model comparison to allow users to investigate the outputs of the modeling systems.
In this paper, we focused on highlighting three different case studies: comparing multiple modeling systems for one sediment core with a continuously deposited succession of dating points (CS1), for one sediment core with scattered dating points (CS2), and for multiple sediment cores (CS3).
For the first case study (CS1), we showed how we facilitate the output data from all modeling systems to create an ensemble age-depth model. In the special case of scattered dating points (CS2), we introduced an adapted method that uses independent proxy data to assess the performance of each modeling system in representing lithological changes. Based on this evaluation, we reproduced the characteristics of an existing age-depth model (Lake Ilirney, EN18208) without removing age determination data.
For multiple sediment cores (CS3) we found that when considering the Pleistocene-Holocene transition, the main regime changes in sedimentation rates do not occur synchronously for all lakes.
We linked this behavior to the uncertainty within the dating and modeling process, as well as the local variability in catchment settings affecting the accumulation rates of the sediment cores within the collection near the glacial-interglacial transition.
The three dominating polyzwitterion families, polyphosphatidylcholines, polycarboxybetaines, and polysulfobetaines, all of which provide high fouling resistance, have been complemented by a fourth one recently, the so-called polysulfabetaines that combine ammonium with sulfate moieties.
To elucidate the relationship between their structure and antifouling potential, coatings of a set of systematically varied poly(sulfabetaine methacrylate)s are investigated.
In particular, the effects of the spacer groups, either separating the zwitterionic units from the polymer backbone, or the cationic from the anionic charges, are explored, studying the resistance against non-specific protein adsorption and the accumulation of single species of marine biofouling organisms.
All polysulfabetaines are at least as effective, or even more potent than the structurally closely related standard poly(sulfobetaine methacrylate).
Their resistance against proteins and fouling organisms can be tuned via the betaine-to-backbone spacer.
Overall, the polysulfabetaine coatings with the shorter ethylene spacer show higher resistance against non-specific adsorption of proteins, in particular of lysozyme, or against colonization by diatoms.
This may result from the higher steric constraints of the polymer attached zwitterions, favoring particularly advantageous conformations.
Moreover, a shorter spacer between the oppositely charged ionic groups of the zwitterionic moiety reduces the settlement of cyprid larvae more effectively.
The growing number of wheat-related allergies worldwide has resulted in a new trend towards gluten-free alternatives. In this context, alternative cereals such as sorghum and oats are attracting new interest. Given the limited data available, the question of whether these cereals are completely safe and gluten-free for allergy sufferers remains open. One of the key steps in protein research is their efficient extraction. In this work, the Osborne sequential extraction method was developed and optimized using the response surface methodology in order to fractionate oat proteins. An optimized desirability of 0.986 was achieved with an extraction time of 4.7 min, a speed of 6, and a sample/solvent ratio of 5. The corresponding optimized responses were 8.7, 4.0, and 5.1% for the extraction yields of the avenin, avenalin, and albumin/globulin fractions, respectively. Further characterization of the extracts was carried out on 24 homogeneous and commercial oat samples via LC-MS/MS, targeting six potentially allergenic proteins. The avenin-E protein featured prominently, with relative contents of 60.7, 32.2, 58.0, and 59.8% in the total extract, avenin, avenalin, and albumin/globulin fractions, respectively, while the Avenin-3, ATI-2, avenin, SSG2, and SSG1 proteins in the total extract showed levels of 16.4, 9.3, 6.6, 4.8, and 2.2%, respectively. The preliminary results of an ELISA performed on the different fractions revealed low levels of gluten (from 1.24 ± 0.14 to 3.61 ± 0.16 mg/kg), which were well below the threshold limit of 20 mg/kg. These results support the hypothesis that oats can be a safe food for people suffering from cereal-related allergies. These results open the door to further studies into the comprehensive characterization of oat proteins.
Marine phytoplankton are responsible for about half of the photosynthesis on Earth. Many are mixotrophs, combining photosynthesis with heterotrophic assimilation of organic carbon, but the relative contribution of these two lifestyles is unclear.
Here single-cell measurements reveal that Prochlorococcus at the base of the photic zone in the Eastern Mediterranean Sea obtain only similar to 20% of carbon required for growth by photosynthesis.
This is supported by laboratory-calibrated calculations based on photo-physiology parameters and compared with in situ growth rates.
Agent-based simulations show that mixotrophic cells could grow tens of metres deeper than obligate photo-autotrophs, deepening the nutricline by similar to 20 m.
Time series from the North Atlantic and North Pacific indicate that, during thermal stratification, on average 8-10% of the Prochlorococcus cells live without enough light to sustain obligate photo-autotrophic populations.
Together, these results suggest that mixotrophy underpins the ecological success of a large fraction of the global Prochlorococcus population and its collective genetic diversity.