Summary
D14 and KAI2 receptors enable plants to distinguish between strigolactones (SLs) and karrikins (KARs), respectively, in order to trigger appropriate environmental and developmental responses. ...Both receptors are related to the regulation of arbuscular mycorrhiza (AM) formation and are members of the RsbQ‐like family of α,β‐hydrolases. DLK2 proteins, whose function remains unknown, constitute a third clade from the RsbQ‐like protein family. We investigated whether the tomato SlDLK2 is a new regulatory component in the AM symbiosis.
Genetic approaches were conducted to analyze SlDLK2 expression and to understand SlDLK2 function in AM symbiosis.
We show that SlDLK2 expression in roots is AM‐dependent and is associated with cells containing arbuscules. SlDLK2 ectopic expression arrests arbuscule branching and downregulates AM‐responsive genes, even in the absence of symbiosis; while the opposite effect was observed upon SlDLK2 silencing. Moreover, SlDLK2 overexpression in Medicago truncatula roots showed the same altered phenotype observed in tomato roots. Interestingly, SlDLK2 interacts with DELLA, a protein that regulates arbuscule formation/degradation in AM roots.
We propose that SlDLK2 is a new component of the complex plant‐mediated mechanism regulating the life cycle of arbuscules in AM symbiosis.
It is highly likely that phytoplanktonic organisms will interact with MPs in the ocean, and consequently with the pollutants sorbed onto their surfaces. Microalgae play an essential role in ...maintaining the balance of the marine ecosystem due to the fact that they are a primary producer and the base of marine trophic chains. Therefore, their fitness represents an important index in the assessment of water quality. The objectives of this study were i) to assess the toxicity of MPs and the pesticide chlorpyrifos (CPF) to the microalgae, Isochrysis galbana, clone t-ISO and ii) to ascertain whether the presence of MPs affects the toxicity of CPF. Microalgae growth rate was selected as the endpoint and a commercial virgin PE micronized powder was chosen as a micro-plastic model, with mean size ranging from 2 to 6 µm, assayed until 25 mg L−1. CPF was tested at concentrations ranging from 0 to 4 mg L−1. A constant concentration of MPs (5 mg L−1) was loaded with increasing doses of CPF (0–3 mg L−1) with a 2 h incubation period. Bioassays were performed at 20 °C, in glass tubes of 50 ml, with air and constant light and an exposure time of 72 h. Cell counts were performed using a Coulter Counter Multisizer III and HPLC was used to quantify the partition of this pollutant among MPs and water. Although microalgae growth was not impacted by MPs, growth was clearly affected by exposure to CPF from 2 mg L−1 and above, with a total growth inhibition at concentrations over 3 mg L−1. Subsequent to incubation, 80% of CPF was sorbed onto MP surfaces. Two different dose-response curves resulted from CPF bioassays depending on the presence of MP, with lower percentages of inhibition when CPF was presented through MP. Thus, the adsorption of CPF onto MP surfaces modulates the toxicity of CPF on I. galbana growth through a reduction in its toxicity, as CPF is adsorbed onto MP surfaces which are less bio-available to the algal cells.
•Acute toxicity of polyethylene MPs on the microalgae Isochrysis galbana was assessed.•Microalgae growth was not affected by exposure to microplastics until 25 mg L–1.•Chlorpyrifos affected algae growth from 2 mg L–1 and total inhibition > 3 mg L–1.•MPs reduced chlorpyrifos toxicity due to its adsorption onto MP surfaces.
Nowadays, most of industries are optimizing their processes to make their products more competitive. In the composites manufacturing industry, there is a big gap between the almost fully automated ...processes and those which require an intensive labor‐work. Although it has many advantages, the resin infusion process is characterized for its lack of automation. As a consequence, the results are strongly dependent on the process boundaries, the operator skills and expertise, and the result is usually far away from the optimum. In this work, the application of a novel methodology and its capability to maximize the mechanical properties of infusion‐manufactured composite materials is presented. After manufacturing stitched and unstitched materials at different impregnation velocities, an optimum value was assessed. The application of this value during the manufacture has increased the tensile and impact properties.
Background
Previous evidence showed altered lumbar multifidus (LM) activation in populations with chronic nonspecific low back pain (LBP). We aimed to investigate the test–retest and inter‐examiner ...reliability of ultrasound imaging (US) for assessing LM thickness at rest and activation during the active straight leg raise test (ASLR) and the association between thickness changes with clinical outcomes.
Methods
Fifty‐two patients with LBP and two examiners (one experienced and one novice) participated in this study. A total of 18 B‐mode images at L4–L5 or L5–S1 level (both sides, 3 at rest and 6 during ASLR) were collected. For assessing test–retest reliability, the experienced examiner repeated the procedure after 7 days. Intraclass correlation coefficients (ICC), standard error of measurements (SEM) and minimal detectable changes (MDC) were calculated.
Results
Inter‐examiner agreement was good to excellent (ICC3,2 = 0.71–0.92) and test–retest reliability was excellent (ICC3,1 = 0.91–0.98). Mean average of multiple measurements improved the agreement. Greater LM thickness at rest (p < .05) and greater thickness change after 3 s (p < .01) and 10 s (homolateral side, p < .01; contralateral side, p < .05) were associated with less pain intensity.
Conclusions
US is a reliable method to assess the LM thickness at rest and contracted during the ASLR in patients with LBP. The measurement at 3 s after maintaining ASLR, as well as the use of the mean of three measurements, has been shown to be the most reliable method for measuring LM muscle thickness during ASLR.
Digital pulse shape analysis (DPSA) techniques are becoming increasingly important for the study of nuclear reactions since the development of fast digitizers. These techniques allow us to obtain the ...(A, Z) values of the reaction products impinging on the new generation solid-state detectors. In this paper, we present a computationally efficient method to discriminate isotopes with similar energy levels, with the aim of enabling the edge-computing paradigm in future field-programmable gate-array-based acquisition systems. The discrimination of isotope pairs with analogous energy levels has been a topic of interest in the literature, leading to various solutions based on statistical features or convolutional neural networks. Leveraging a valuable dataset obtained from experiments conducted by researchers in the FAZIA Collaboration at the CIME cyclotron in GANIL laboratories, we aim to establish a comparative analysis regarding selectivity and computational efficiency, as this dataset has been employed in several prior publications. Specifically, this work presents an approach to discriminate between pairs of isotopes with similar energies, namely,
C,
Ar, and
Kr, using principal component analysis (PCA) for data preprocessing. Consequently, a linear and cubic machine learning (ML) support vector machine (SVM) classification model was trained and tested, achieving a high identification capability, especially in the cubic one. These results offer improved computational efficiency compared to the previously reported methodologies.
The megalithic cluster of the Gor River valley (Andalusia, Spain) is one of the biggest dolmenic groups in Europe, made up of 151 preserved megaliths. In spite of this high number of known monuments, ...increasing loss and destruction of many of the graves has taken place during the last decades due to enormous soil erosion and anthropogenic activities. With the aim of recording the location of these lost megaliths, Digital Terrain Models and LiDAR data have been used to analyse the terrain showing a high quantity of structures that seem similar to those actually documented in the zone but that were not noticed until now. These possible new burial mounds have been tested by archaeological surface survey, choosing three contrasting areas as samples. Results have shown a high success rate for this methodology, even allowing the discovery of new megalithic graves in heavily researched areas. We interpret the likely higher number of burial mounds in the area to indicate greater territorial control in boundary areas between 4th and 3rd millennium BC.
Habitats with alkaline edaphic substrates are often associated with plant speciation and diversification. The tribe Alysseae, in the family Brassicaceae, epitomizes this evolutionary trend. In this ...lineage, some genera, like Hormathophylla, can serve as a good case for testing the evolutionary framework. This genus is centered in the western Mediterranean. It grows on different substrates, but mostly on alkaline soils. It has been suggested that diversification in many lineages of the tribe Alysseae and in the genus Hormathophylla is linked to a tolerance for high levels of Mg+2 in xeric environments. In this study, we investigated the controversial phylogenetic placement of Hormathophylla in the tribe, the generic limits and the evolutionary relationships between the species using ribosomal and plastid DNA sequences. We also examined the putative association between the evolution of different ploidy levels, trichome morphology and the type of substrates. Our analyses demonstrated the monophyly of the genus Hormathophylla including all previously described species. Nuclear sequences revealed two lineages that differ in basic chromosome numbers (x = 7 and x = 8 or derived 11, 15) and in their trichome morphology. Contrasting results with plastid genes indicates more complex relationships between these two lineages involving recent hybridization processes. We also found an association between chloroplast haplotypes and substrate, especially in populations growing on dolomites. Finally, our dated phylogeny demonstrates that the origin of the genus took place in the mid-Miocene, during the establishment of temporal land bridges between the Tethys and Paratethys seas, with a later diversification during the upper Pliocene.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
The Tabernas–Alhabia Basin is a structural depression situated in the province of Almería, southeastern Spain. The basin is filled with Neogene, Pliocene, and Pleistocene sediments resting ...discordantly on a Paleozoic metamorphic basement. During the marine Tortonian sedimentation, a bed of breccia (Gordo megabed) was formed. It consists of rotated sedimentary megablocks commonly capped and/or surrounded by a polymict breccia composed mainly of up to dm‐sized clasts of the crystalline (schist) basement. Previous work has suggested the bed to be a seismite corresponding to events induced by earthquakes. Here, we link the formation of the Gordo megabed with an ∼5 km wide, rimmed depression with exposed breccias on the northern flank of the Sierra de Gádor mountain. This semicircular structure, developed in mainly schists and dolostone of the basement, is delimited to the W, S, and E by an up to 350 m high escarpment with overturned stratigraphy. Toward the north, this crater‐like structure opens toward the Gordo megabed of the Tabernas Basin. In the southern sector, the overturned strata transform outward for into a blocky allochthonous breccia with decreasing thickness and clast size. In the interior of the structure, there are occurrences of graded breccia and arenite superposed on a blocky, autochthonous breccia. Based on the presence of mineralogical shock metamorphic evidence, potential shatter cones, and a high Ir anomaly (∼500 ppb) as well as the position of the structure near the town of Alhama de Almería, we propose to call it the Alhama de Almería impact structure.
The optimization of the mechanical properties of composite materials has been a challenge since these materials were first used, especially in aeronautics. Reduced energy consumption, safety and ...reliability are mandatory to achieve a sustainable use of composite materials. The mechanical properties of composites are closely related to the amount of defects in the materials. Voids are known as one of the most important defect sources in resin film infusion (RFI)-manufactured composites. Minimizing the defect content leads to maximized mechanical properties and lightweight design. In this paper, a novel methodology based on computer vision is applied to control the impregnation velocity, reduce the void content and enhance the impact properties. Optimized drop-impact properties were found once the impregnation velocity was analyzed and optimized. Its application in both conventional and stitching-reinforced composites concludes with an improvement in the damage threshold load, peak force and damaged area. Although stitching tends to generate additional voids and reduces in-plane properties, the reduction in the damaged area means a positive balance in the mechanical properties. At the same time, the novel methodology provides the RFI process with a noticeable level of automation and control. Consequently, the industrial interest and the range of applications of this process are enhanced.
Liquid composite manufacturing techniques, mainly applied in the transport industry, have been studied and optimized for decades while defect analysis and its minimization have been a goal to ...increase reliability and mechanical performance. Researchers have found that many process parameters have a strong influence on the mechanical behavior of composite structures where the flow front velocity, closely related to voids, plays a considerable role. In this work, the optimal flow front velocity was evaluated and controlled using a computer vision system for different laminates improving the mechanical tensile properties and void content. Enhanced mechanical tensile properties were found using a feedback flow-controller vision system which was able to keep the optimal flow front velocity constant to reduce the air traps among tows and fibers. Tensile strength was enhanced up to 18% for fiber orientation at 0° and 3.3% at 90°, whereas tensile modulus was increased up to 18.4% for fibers at 0° and 8.7% at 90°. A novel methodology is presented through this work, aiming to improve the robustness of resin film infusion (RFI) processes while ensuring the quality of the composite material.
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