Costa Rica is considered a hot spot for biodiversity and wildlife conservation in Central America, and sea turtles are a good example of this. Largely distributed along both the Caribbean and Pacific ...coast, adult females of five of the seven extant sea turtle species select beaches on both coasts as their breeding sites. Although Green Sea Turtles (Chelonia mydas), Leatherback Sea Turtles (Dermochelys coriacea), Hawksbill Sea Turtles (Eretmochelys imbricata), and Olive Ridley Sea Turtles (Lepidochelys olivacea) have been extensively studied in Costa Rica, little information regarding Loggerhead Sea Turtles (Caretta caretta) is available. Thus, we present an exhaustive data record of every Loggerhead encountered at Tortuguero beach (northeastern Caribbean coast of Costa Rica) over the past 60 yr. We collected Loggerhead nesting data between 1957 and 2021 through daytime and nocturnal monitoring activities. We documented 14 Loggerhead Sea Turtle nesting attempts between 1957 and 2021 at Tortuguero. Among them, seven nested successfully, four did not lay eggs, and one's fate is unknown. Additionally, two turtles were killed by jaguars. Mean minimum curve carapace length (CCLmin) measurements for Loggerheads was 98.2 ± 3.7 cm (range, 90.0–101.4 cm). Finally, we found that every encounter occurred between April and July, which coincides with the Loggerhead nesting season in the Northwest Atlantic. Our study is the first assessment of Loggerhead Sea Turtles nesting in Costa Rica, bringing to light new records for this species in the Caribbean Sea.
Our aim was to examine the effect of water stress on plant growth and development of two native plant species (Tetraclinis articulata and Crithmum maritimum) and on microbial community composition ...and activity in the rhizosphere soil, following the addition of an organic amendment, namely sugar beet residue (SBR), and/or the inoculation with an arbuscular mycorrhizal (AM) fungus, namely Glomus mosseae, in a non-sterile heavy metalpolluted soil. The AM inoculation did not have any significant effect on plant growth of both species. In T. articulata, SBR increased shoot growth, foliar P, total phospholipid fatty acids (PLFA), fungi-related PLFA, AM fungi-related neutral lipid fatty acid, bacterial grampositive/gram-negative PLFA ratio and the ß-glucosidase and dehydrogenase activities. SBR and AM inoculation increased phosphatase activity in T. articulata plants grown under drought conditions. In both plants, there was a synergistic effect between AM inoculation and SBR on mycorrhizal colonisation under drought conditions. In C. maritimum, the increase produced by the SBR on total amounts of PLFA, bacterial gram-positive-related PLFA and bacterial gram-negative-related PLFA was considerably higher under drought conditions. Our results suggest that the effectiveness of the amendment with regard to stimulating microbial communities and plant growth was largely limited by drought, particularly for plant species with a low degree of mycorrhizal colonisation.
Cylindrical nanowires synthesized by controlled electrodeposition constitute excellent strategic candidates to engineer magnetic domain configurations. In this work, multisegmented CoNi/Ni nanowires ...are synthesized for tailoring a periodic magnetic structure determined by the balance between magnetocrystalline and magnetostatic energies. High-resolution Transmission Electron Microscopy confirms the segmented growth and the sharp transition between layers. Although both CoNi and Ni segments have similar fcc cubic crystal symmetry, their magnetic configuration is quite different as experimentally revealed by Magnetic Force Microscopy (MFM) imaging. While the Ni segments are single domain with axial magnetization direction, the CoNi segments present two main configurations: a single vortex state or a complex multivortex magnetic configuration, which is further interpreted with the help of micromagnetic simulations. This original outcome is ascribed to the tight competition between anisotropies. The almost monocrystalline fcc structure of the CoNi segments, as revealed by the electron diffraction patterns, which is atypical for its composition, contributes to balance the magnetocrystalline and shape anisotropies. The results of MFM measurements performed under in-plane magnetic field demonstrate that it is possible to switch from the multivortex configuration to a single vortex configuration with low magnetic fields.
This work presents the first tests performed with radiochromic films and a new Micro‒Opto‒Electro-Mechanical system (MOEMS) for in situ dosimetry evaluation in radiotherapy in real time. We present a ...new device and methodology that overcomes the traditional limitation of time-delay in radiochromic film analysis by turning a passive detector into an active sensor. The proposed system consists mainly of an optical sensor based on light emitting diodes and photodetectors controlled by both customized electronic circuit and graphical user interface, which enables optical measurements directly. We show the first trials performed in a low‒energy proton cyclotron with this MOEMS by using gafchromic EBT3 films. Results show the feasibility of using this system for in situ dose evaluations. Further adaptation is ongoing to develop a full real‒time active detector by integrating MOEM multi‒arrays and films in flexible printed circuits. Hence, we point to improve the clinical application of radiochromic films with the aim to optimize radiotherapy treatment verifications.
The nickel/zirconia (Ni/ZrO2) interface plays a key role in the performance of the anode of solid oxide fuel cells (SOFC) and it is therefore important to understand the interaction between nickel ...nanoparticles and the ZrO2 surface. Here, we have described the interaction of five Nin (n = 1–5) clusters with the (111) surface of cubic zirconia, c‐ZrO2(111), using spin polarized density functional theory (DFT) calculations with inclusion of long‐range dispersion forces. We have systematically evaluated the geometric and electronic structure of different cluster configurations and sizes and shown how the clusters interact with the oxygen and zirconium surface atoms. The cluster‐surface interaction is characterized by a charge transfer from the Ni clusters to the surface. From calculations of the hopping rate and clustering energies, we have demonstrated that Ni atoms prefer to aggregate rather than wet the surface and we would therefore suggest that modifications in the synthesis could be needed to modify the coalescence of the supported metal particles of this catalytic system.
Autochthonous microorganisms a consortium of arbuscular-mycorrhizal (AM) fungi and Bacillus thuringiensis (Bt) were assayed and compared to Rhizophagus intraradices (Ri), Bacillus megaterium (Bm) or ...Pseudomonas putida (Psp) and non-inoculation on Trifolium repens in a natural arid soil under drought conditions. The autochthonous bacteria Bt and the allochthonous bacteria Psp increased nutrients and the relative water content and decreased stomatal conductance, electrolyte leakage, proline and APX activity, indicating their abilities to alleviate the drought stress. Mycorrhizal inoculation significantly enhanced plant growth, nutrient uptake and the relative water content, particularly when associated with specific bacteria minimizing drought stress-imposed effects. Specific combinations of autochthonous or allochthonous inoculants also contributed to plant drought tolerance by changing proline and antioxidative activities. However, non-inoculated plants had low relative water and nutrients contents, shoot proline accumulation and glutathione reductase activity, but the highest superoxide dismutase activity, stomatal conductance and electrolyte leakage. Microbial activities irrespective of the microbial origin seem to be coordinately functioning in the plant as an adaptive response to modulated water stress tolerance and minimizing the stress damage. The autochthonous AM fungi with Bt or Psp and those allochthonous Ri with Bm or Psp inoculants increased water stress alleviation. The autochthonous Bt showed the greatest ability to survive under high osmotic stress compared to the allochthonous strains, but when single inoculated or associated with Ri or AM fungi were similarly efficient in terms of physiological and nutritional status and in increasing plant drought tolerance, attenuating and compensating for the detrimental effect of water limitation.
Fungal pellets are hierarchical systems that can be found in an ample variety of applications. Modeling transport phenomena in this type of systems is a challenging but necessary task to provide ...knowledge-based processes that improve the outcome of their biotechnological applications. In this work, an upscaled model for total mass and momentum transport in fungal pellets is implemented and analyzed, using elements of the volume averaging and adjoint homogenization methods departing from the governing equations at the microscale in the intracellular and extracellular phases. The biomass is assumed to be composed of a non-Newtonian fluid and the organelles impervious to momentum transport are modeled as a rigid solid phase. The upscaled equations contain effective-medium coefficients, which are predicted from the solution of adjoint closure problems in a three-dimensional periodic domains representative of the microstructure. The construction of these domains was performed for Laccaria trichodermophora based on observations of actual biological structures. The upscaled model was validated with direct numerical simulations in homogeneous portions of the pellets core. It is shown that no significant differences are observed when the dolipores are open or closed to fluid flow. By comparing the predictions of the average velocity in the extracellular phase resulting from the upscaled model with those from the classical Darcy equation (i.e., assuming that the biomass is a solid phase) the contribution of the intracellular fluid phase was evidenced. This work sets the foundations for further studies dedicated to transport phenomena in this type of systems.
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•An effective-medium model for fluid flow in fungal pellets was implemented.•Laccaria trichodermophora pellets were characterized and used for modeling.•The model was validated with direct numerical simulations.•Flow through the dolipore does not significantly affect momentum transport.•Classical Darcy’s law is not applicable for this type of system.
Procyonids are reservoirs of many zoonotic infectious diseases, including tick-borne pathogens. The role of coatis (
Nasua nasua
) in the epidemiology of piroplasmids and
Rickettsia
has not been ...fully addressed in Brazil. To molecularly study these agents in coatis and associated ticks, animals were sampled in two urban areas in Midwestern Brazil. Blood (
n
= 163) and tick (
n
= 248) DNA samples were screened by PCR assays targeting the 18S rRNA and
gltA
genes of piroplasmids and
Rickettsia
spp., respectively. Positive samples were further molecularly tested targeting
cox-1
,
cox-3
,
β
-
tubulin
,
cytB
, and
hsp
70 (piroplasmid) and
ompA
,
ompB
, and
htrA
17-kDa (
Rickettsia
spp.) genes, sequenced and phylogenetically analyzed. All coatis’ blood samples were negative for piroplasmids, whereas five pools of ticks (2%) were positive for two different sequences of
Babesia
spp.. The first from
Amblyomma sculptum
nymphs was close (i.e., ≥ 99% nucleotide identity) to a
Babesia
sp. previously found in capybaras (
Hydrochoerus hydrochaeris
); the second from
Amblyomma dubitatum
nymphs and
Amblyomma
spp. larvae was identical (100% nucleotide identity) to a
Babesia
sp. detected in opossums (
Didelphis albiventris
) and associated ticks. Four samples (0.8%) were positive by PCR to two different
Rickettsia
spp. sequences, being the first from
Amblyomma
sp. larva identical to
Rickettsia belli
and the second from
A. dubitatum
nymph identical to
Rickettsia
species from Spotted Fever Group (SFG). The detection of piroplasmids and SFG
Rickettsia
sp. highlights the importance of
Amblyomma
spp. in the maintenance of tick-borne agents in urban parks where humans and wild and domestic animals are living in sympatry.
Abstract
SHADOWS 1, 2 is an intended future beam dump experiment in the CERN North Area, aiming to search for feebly interacting particles (FIPs) 3 created in 400 GeV/c proton interactions. Due to ...its proposed off-axis location alongside the K12 beamline 4, the SHADOWS detector can be placed potentially very close to the beam dump, enabling it to search for FIPs in unexplored parts of the parameter space. In order to guarantee good quality of a potential signal, it is crucial to reduce any backgrounds of Standard Model particles as much as possible. The dominant background downstream the beam dump is caused by muons 1. This introduces the need of a dedicated muon sweeping system consisting of magnetised iron blocks (MIBs) to actively mitigate this background component. We present the conceptional design studies in the framework of the Conventional Beams Working Group of the Physics Beyond Colliders Initiative at CERN 5, 6.
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