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Here, we describe patterns of reproduction and flight phenology of putative Phloeosinus punctatus in giant sequoia groves and compare morphology and genotypes of beetles from sympatric giant sequoia (Sequoiadendron giganteum) and California incense-cedar (Calocedrus decurrens). Surveys conducted in 2022 revealed that numerous branches fall from giant sequoia crowns (on average ∼30 branches/tree), with 20%–50% of trees per site shedding branches, depositing breeding material for beetles on the forest floor that subsequently becomes colonized. When noninfested branches cut from mature giant sequoias were placed at the ground surface, they were colonized by P. punctatus and produced an average of 28 beetles/kg branch. Climbing and examination of sequoia crowns in 2023 showed that 75% of mature trees across 11 groves showed evidence of adult beetle entrance holes in their crowns. In 2021, tests with sticky traps showed that beetles alighted on fallen branches from 20th May to 20th August (peak landing: 2nd July); a logistic model developed from emergence data in 2021 and 2022 predicts the emergence of F1 offspring from branches between 10th July and 1st September (peak emergence: 8th August). Beetles emerging from giant sequoia preferred to settle on giant sequoia, did not reproduce in incense-cedar, and diverged morphologically from beetles emerging from incense-cedar. However, phylogenetic analysis of three genes (28S, CAD, and COI) revealed no clear pattern of sequence divergence, suggesting a single species (P. punctatus) that colonizes both hosts, though cryptic speciation may not be detectable with standard barcoding genes. Ecological and potential management implications are discussed. [ABSTRACT FROM AUTHOR]

The article reports the first case of Austropuccinia psidii causing rust disease in Europe on Syzygium buxifolium bonsai plants. The pathogen was identified through microscopy and DNA sequencing, with infected plants removed from sale and destroyed. The presence of A. psidii poses a phytosanitary risk in Europe, particularly in regions with suitable climates and native host species. The study highlights the potential impact of international plant trade on the spread of invasive fungal pathogens. [Extracted from the article]

Armillaria species show considerable variation in ecological roles and virulence, from mycorrhizae and saprophytes to important root pathogens of trees and horticultural crops. We studied two Armillaria species that can be found in coniferous forests of northwestern USA and southwestern Canada. Armillaria altimontana not only is considered as a weak, opportunistic pathogen of coniferous trees, but it also appears to exhibit in situ biological control against A. solidipes, formerly North American A. ostoyae, which is considered a virulent pathogen of coniferous trees. Here, we describe their genome assemblies and present a functional annotation of the predicted genes and proteins for the two Armillaria species that exhibit contrasting ecological roles. In addition, the soil microbial communities were examined in association with the two Armillaria species within a 45-year-old plantation of western white pine (Pinus monticola) in northern Idaho, USA, where A. altimontana was associated with improved tree growth and survival, while A. solidipes was associated with reduced growth and survival. The results from this study reveal a high similarity between the genomes of the beneficial/non-pathogenic A. altimontana and pathogenic A. solidipes; however, many relatively small differences in gene content were identified that could contribute to differences in ecological lifestyles and interactions with woody hosts and soil microbial communities. [ABSTRACT FROM AUTHOR]

Copyright of Cirugía Pediátrica (English Edition) is the property of Sociedad Espanola de Cirurgia Pediatrica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cirugía Pediátrica (English Edition) is the property of Sociedad Espanola de Cirurgia Pediatrica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cirugía Pediátrica (English Edition) is the property of Sociedad Espanola de Cirurgia Pediatrica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Biociências is the property of Revista Biociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An efficient xanthate-based method for the preparation of azaspirocyclic cyclohexadienones via an ipso oxidative radical cyclization of p-oxygenated N-benzylacetamides and N-phenetylacetamide is described. [ABSTRACT FROM AUTHOR]

We show that the polycrystalline perovskite antiferromagnet Pr[sub 0.5]Sr[sub 0.5]MnO[sub 3] exhibits a giant anisotropic magnetostriction (λ[sub t] = 1.5 × 10[sup -3] at T= 25 K and H = 14.2 T) contrary to much smaller λ[sub t] (<0.1 × 10[sup -3]) found in most other three-dimensional manganites. The value of λ[sub t] decreases rapidly as the Néel temperature is approached from below, but an unusually high value of λ[sub t] is also found below the ferromagnetic Curie temperature. We suggest that the magnetic-field-induced antiferromagnetic-to-ferromagnetic transition is accompanied by a structural transition from orthorhombic to tetragonal symmetry and attribute the giant anisotropic effect to the preferential growth of the orbital disordered tetragonal (ferromagnetic) domains along the field direction in the e[sub g]-d[sub x[sup 2]- y[sub 2] orbital ordered orthorhombic (antiferromagnetic) matrix. [ABSTRACT FROM AUTHOR]

Since the discovery of the spin Seebeck effect (SSE), much attention has been devoted to the study of the interaction between heat, spin, and charge in magnetic systems. The SSE refers to the generation of a spin current upon the application of a thermal gradient and detected by means of the inverse spin Hall effect. Conversely, the spin Peltier effect (SPE) refers to the generation of a heat current as a result of a spin current induced by the spin Hall effect. Here we report a strong enhancement of both the SSE and SPE in Fe3O4/Pt multilayered thin films at room temperature as a result of an increased thermo-spin conversion efficiency in the multilayers. These results open the possibility to design thin film heterostructures that may boost the application of thermal spin currents in spintronics. [ABSTRACT FROM AUTHOR]

We review the current status of the use of focused electron beam induced deposition (FEBID) for the growth of magnetic nanostructures. This technique relies on the local dissociation of a precursor gas by means of an electron beam. The most promising results have been obtained using the Co2(CO)8 precursor, where the Co content in the grown nanodeposited material can be tailored up to more than 95 at.%. Functional behaviour of these Co nanodeposits has been observed in applications such as arrays of magnetic dots for information storage and catalytic growth, magnetic tips for scanning probe microscopes, nano-Hall sensors for bead detection, nano-actuated magnetomechanical systems and nanowires for domain-wall manipulation. The review also covers interesting results observed in Fe-based and alloyed nanodeposits. Advantages and disadvantages of FEBID for the growth of magnetic nanostructures are discussed in the article as well as possible future directions in this field. [ABSTRACT FROM AUTHOR]

Remanent state and magnetization reversal processes of a series of cobalt antidot arrays with a fixed hole diameter (d ≈ 55 nm) and an array periodicity (p) ranging between 95 and 524 nm were studied by in situ Lorentz microscopy (LM) as a function of the magnetic field. At remanence, defocused LM images showed the periodicity dependence of the magnetic states inside the lattice. A remarkable transition was observed in the type of domain structures as a function of p: for the large periodicities (p > 300 nm), conventional 90° and 180° domain walls were formed, whereas in small-period antidot arrays (p ≦ 160 nm) magnetic superdomain walls (SDWs) were nucleated to separate regions with different average magnetization direction, the so-called magnetic superdomains. In the SDW regime, a low-frequency Fourier filtering method was implemented to allow a quantitative analysis of the LM images by the transport of intensity equation method. In situ LM experiments under applied magnetic fields were performed to study the reversal magnetization process in a particular array (p = 160 nm), and clear differences were observed as a function of the magnetic field orientation. The switching process under magnetic fields parallel to the horizontal antidot rows occurs in two stages: the system first nucleates and propagates horizontal SDWs, parallel to the field. Then, at higher magnetic fields, vertical SDWs, perpendicular to the field, appear before saturation. When the magnetic field is applied at 45° with respect to the antidot rows, both horizontal and vertical SDWs are nucleated and propagated simultaneously. All the experiments were successfully correlated with micromagnetic simulations. The current study sheds new light on the magnetization reversal processes of antidot arrays and opens new possibilities of exploiting the potential of high-resolution in situ LM and new data analysis procedures to probe magnetization processes in nanomagnetism, particularly in periodic arrays of nanomagnets. [ABSTRACT FROM AUTHOR]

We systematically study the effect of oxygen content on the magneto-transport and microstructure of Fe:O:C nanowires deposited by focused-electron-beam-induced (FEBID) deposition. The Fe/O ratio can be varied with an Fe content varying between [?] 50 and 80 at.% with overall low C content ([?]16 +- 3 at.%) by adding H2O during the deposition while keeping the beam parameters constant as measured by energy dispersive x-ray (EDX) spectroscopy. The room-temperature magnetic properties for deposits with an Fe content of 66-71 at.% are investigated using the magneto-optical Kerr effect (MOKE) and electric magneto-transport measurements. The nanostructure of the deposits is investigated through cross-sectional high-resolution transmission electron microscopy (HRTEM) imaging, allowing us to link the observed magneto-resistance and resistivity to the transport mechanism in the deposits. These results demonstrate that functional magnetic nanostructures can be created, paving the way for new magnetic or even spintronics devices. [ABSTRACT FROM AUTHOR]

We systematically study individual micro- and nanometric polycrystalline cobalt wires grown by focused-electron-beam-induced-deposition. The deposits were grown in a range of aspect ratios varying from 1 up to 26. The minimum lateral dimension of the nanowires was 150 nm, for a thickness of 40 nm. Atomic force microscopy images show beam-current-dependent profiles, associated with different regimes of deposition. The magnetization reversal of individual nanowires is studied by means of the spatially resolved magneto-optical Kerr effect. Abrupt switching is observed, with a systematic dependence on the wire's dimensions. This dependence of the coercive field is understood in magnetostatic terms, and agrees well with previous results on cobalt wires grown with different techniques. The influence of compositional gradients along the structural profile on the magnetic reversal is studied by using micromagnetic simulations. This work demonstrates the feasibility of using this technique to fabricate highly pure magnetic nanostructures, and highlights the advantages and disadvantages of the technique with respect to more conventional ones. [ABSTRACT FROM AUTHOR]

A novel technique to establish atomic-sized contacts in metallic materials is shown. It is based on etching a (sub)micrometric electrode via a low-energy focused ion beam. The in situ measurements of the nanoconstriction resistance during the etching process permit control of the formation of atomic-sized constrictions with milling time, observing steps in the conductance in the range of the conductance quantum (G0 = 2e2/h), just before entering the tunnelling regime. These constrictions are highly stable with time due to the adherence to a substrate, which allows further studies such as the detailed current-voltage transport investigation reported here. Scanning electron microscopy images are used to correlate the etching process and the constriction microstructure. The high control achieved in the process makes us suggest this technique as a promising route to study physical phenomena in the verge of the metal-tunnel conduction crossover. [ABSTRACT FROM AUTHOR]

Background and Aims The great potential of using nanodevices as delivery systems to specific targets in living organisms was first explored for medical uses. In plants, the same principles can be applied for a broad range of uses, in particular to tackle infections. Nanoparticles tagged to agrochemicals or other substances could reduce the damage to other plant tissues and the amount of chemicals released into the environment. To explore the benefits of applying nanotechnology to agriculture, the first stage is to work out the correct penetration and transport of the nanoparticles into plants. This research is aimed (a) to put forward a number of tools for the detection and analysis of core-shell magnetic nanoparticles introduced into plants and (b) to assess the use of such magnetic nanoparticles for their concentration in selected plant tissues by magnetic field gradients. Methods Cucurbita pepo plants were cultivated in vitro and treated with carbon-coated Fe nanoparticles. Different microscopy techniques were used for the detection and analysis of these magnetic nanoparticles, ranging from conventional light microscopy to confocal and electron microscopy. Key Results Penetration and translocation of magnetic nanoparticles in whole living plants and into plant cells were determined. The magnetic character allowed nanoparticles to be positioned in the desired plant tissue by applying a magnetic field gradient there; also the graphitic shell made good visualization possible using different microscopy techniques. Conclusions The results open a wide range of possibilities for using magnetic nanoparticles in general plant research and agronomy. The nanoparticles can be charged with different substances, introduced within the plants and, if necessary, concentrated into localized areas by using magnets. Also simple or more complex microscopical techniques can be used in localization studies. [ABSTRACT FROM AUTHOR]