The magnetization reversal processes are discussed for exchange-coupled ferromagnetic hard/soft bilayers made from Co0.66Cr0.22Pt0.12 (10 and 20 nm)/Ni (from 0 to 40 nm) films with out-of-plane and ...in-plane magnetic easy axes respectively, based on room temperature hysteresis loops and first-order reversal curve analysis. On increasing the Ni layer thicknesses, the easy axis of the bilayer reorients from out-of-plane to in-plane. An exchange bias effect, consisting of a shift of the in-plane minor hysteresis loops along the field axis, was observed at room temperature after in-plane saturation. This effect was associated with specific ferromagnetic domain configurations experimentally determined by polarized neutron reflectivity. On the other hand, perpendicular exchange bias effect was revealed from the out-of-plane hysteresis loops and it was attributed to residual domains in the magnetically hard layer.
The exchange bias of antiferromagnetic-ferromagnetic (AFM-FM) bilayers is found to be strongly dependent on the ferromagnetic spin configuration. The widely accepted inverse proportionality of the ...exchange bias field with the ferromagnetic thickness is broken in FM layers thinner than the FM correlation length. Moreover, an anomalous thermal dependence of both exchange bias field and coercivity is also found. A model based on springlike domain walls parallel to the AFM-FM interface quantitatively accounts for the experimental results and, in particular, for the deviation from the inverse proportionality law. These results reveal the active role the ferromagnetic spin structure plays in AFM-FM hybrids which leads to a new paradigm of the exchange bias phenomenon.
Background
Globally, many undescribed fungal taxa reside in the hyperdiverse, yet undersampled, tropics. These species are under increasing threat from habitat destruction by expanding extractive ...industry, in addition to global climate change and other threats. Reserva Los Cedros is a primary cloud forest reserve of ~ 5256 ha, and is among the last unlogged watersheds on the western slope of the Ecuadorian Andes. No major fungal survey has been done there, presenting an opportunity to document fungi in primary forest in an underrepresented habitat and location. Above-ground surveys from 2008 to 2019 resulted in 1760 vouchered collections, cataloged and deposited at QCNE in Ecuador, mostly Agaricales sensu lato and Xylariales. We document diversity using a combination of ITS barcode sequencing and digital photography, and share the information via public repositories (GenBank & iNaturalist).
Results
Preliminary identifications indicate the presence of at least 727 unique fungal species within the Reserve, representing 4 phyla, 17 classes, 40 orders, 101 families, and 229 genera. Two taxa at Los Cedros have recently been recommended to the IUCN Fungal Red List Initiative (
Thamnomyces chocöensis
Læssøe and “
Lactocollybia” aurantiaca
Singer), and we add occurrence data for two others already under consideration (
Hygrocybe aphylla
Læssøe & Boertm. and
Lamelloporus americanus
Ryvarden).
Conclusions
Plants and animals are known to exhibit exceptionally high diversity and endemism in the Chocó bioregion, as the fungi do as well. Our collections contribute to understanding this important driver of biodiversity in the Neotropics, as well as illustrating the importance and utility of such data to conservation efforts.
Resumen
Antecedentes
: A nivel mundial muchos taxones fúngicos no descritos residen en los trópicos hiper diversos aunque continúan submuestreados. Estas especies están cada vez más amenazadas por la destrucción del hábitat debido a la expansión de la industria extractivista además del cambio climático global y otras amenazas. Los Cedros es una reserva de bosque nublado primario de ~ 5256 ha y se encuentra entre las últimas cuencas hidrográficas no explotadas en la vertiente occidental de los Andes ecuatorianos. Nunca antes se ha realizado un estudio de diversidad micológica en el sitio, lo que significa una oportunidad para documentar hongos en el bosque primario, en hábitat y ubicación subrepresentatadas. El presente estudio recopila información entre el 2008 y 2019 muestreando material sobre todos los sustratos, reportando 1760 colecciones catalogadas y depositadas en el Fungario del QCNE de Ecuador, en su mayoría Agaricales sensu lato y Xylariales; además se documenta la diversidad mediante secuenciación de códigos de barras ITS y fotografía digital, la información está disponible en repositorios públicos digitales (GenBank e iNaturalist).
Resultados:
La identificación preliminar indica la presencia de al menos 727 especies únicas de hongos dentro de la Reserva, que representan 4 filos, 17 clases, 40 órdenes, 101 familias y 229 géneros. Recientemente dos taxones en Los Cedros se recomendaron a la Iniciativa de Lista Roja de Hongos de la UICN (
Thamnomyces chocöensis
Læssøe y
“Lactocollybia” aurantiaca
Singer) y agregamos datos de presencia de otros dos que ya estaban bajo consideración (
Hygrocybe aphylla
Læssøe & Boertm. y
Lamelloporus americanus
Ryvarden).
Conclusiones:
Se sabe que plantas y animales exhiben una diversidad y endemismo excepcionalmente altos en la bioregión del Chocó y los hongos no son la excepción. Nuestras colecciones contribuyen a comprender este importante promotor de la biodiversidad en el Neotrópico además de ilustrar la importancia y utilidad de dichos datos para los esfuerzos de conservación.
Summary
Background
Cutaneous malignant melanoma arises from transformed melanocytes de novo or from congenital or acquired melanocytic naevi. We have recently reported that T‐type Ca2+ channels ...(TT‐Cs) are upregulated in human melanoma and play an important role in cell proliferation.
Objectives
To describe for the first time in formalin‐fixed paraffin‐embedded tissue the immunoexpression of TT‐Cs in biopsies of normal skin, acquired melanocytic naevi and melanoma, in order to evaluate their role in melanomagenesis and/or tumour progression, their utility as prognostic markers and their possible use in targeted therapies.
Methods
Tissue samples from normal skin, melanocytic naevi and melanoma were subjected to immunohistochemistry for two TT‐Cs (Cav3.1, Cav3.2); markers of proliferation (Ki67), the cell cycle (cyclin D1), hypoxia (Glut1), vascularization (CD31) and autophagy (LC3); BRAF V600E mutation (VE1) and phosphatase and tensin homologue (PTEN). Immunostaining was evaluated by histoscore. In silico analysis was used to assess the prognostic value of TT‐C overexpression.
Results
TT‐C immunoexpression increased gradually from normal skin to common naevi, dysplastic naevi and melanoma samples, but with differences in the distribution of both isoforms. Particularly, Cav3.2 expression was significantly higher in metastatic melanoma than in primary melanoma. Statistical correlation showed a linear interaction between PTEN loss/BRAF V600E/Cav3.1/LC3/ Ki67/cyclin D1/Cav3.2/Glut1. Disease‐free survival (DFS) and overall survival correlated inversely with overexpression of Cav3.2. DFS also correlated inversely with overexpression of Cav3.1.
Conclusions
TT‐C immunoexpression on melanocytic neoplasms is consistent with our previous in vitro studies and appears to be related to tumour progression. TT‐C upregulation can be considered as a prognostic marker using The Cancer Genome Atlas database. The high expression of Cav3.2 in metastatic melanoma encourages the investigation of the use of TT‐C blockers in targeted therapies.
What's already known about this topic?
Increased expression of voltage‐gated calcium channels is a common finding in several neoplasms.
We have recently reported that T‐type Ca2+ channels (TT‐Cs) are upregulated in human melanoma cells and play an important role in cell proliferation, calcium homeostasis and autophagic flux.
What does this study add?
TT‐C immunoexpression increases gradually from normal skin to common naevi, dysplastic naevi and melanoma samples, and expression of the Cav3.2 isoform is augmented in metastatic vs. primary melanoma.
We demonstrate a significant correlation between Breslow thickness and TT‐C expression, and show a positive correlation between the immunoexpression of Cav3.2 and proliferative/hypoxia markers.
We show a positive association between the expression of the Cav3.1 isoform, the autophagy markers and the presence of the BRAF V600E mutation.
What is the translational message?
These findings open a new avenue of research regarding the use of T‐type blockers in targeted therapies.
Linked Comment: Ellis. Br J Dermatol 2017; 176:1122
Plain language summary available online
Rationale
Clozapine has proven to be superior to other antipsychotic drugs in the treatment of schizophrenia but is under-prescribed due to its potentially severe side effects. Clozapine-induced ...sialorrhea (CIS) is a frequent and extremely uncomfortable side effect, which remains understudied.
Objectives
To examine the prevalence of diurnal and nocturnal CIS in a sample of patients treated with clozapine, and to evaluate its impact on quality of life.
Methods
We conducted a cross-sectional, observational study of 130 patients with schizophrenia spectrum disorders treated with clozapine. The prevalence of CIS was evaluated via specific sialorrhea scales. None of the patients included in the study was receiving a specific treatment for hypersalivation during the study period. Possible associations between sialorrhea and clinical and quality of life variables were analyzed.
Results
Of 130 subjects, 120 (92.3%) suffered from CIS. Eighty-one (62.31%) suffered from diurnal CIS, 115 (88.56%) from nocturnal CIS, and 85 (65.38%) suffered from both. Significant positive associations between quality of life and diurnal CIS (
B
= 0.417;
p
= 2.1e − 6,
R
2
= 0.156) and nocturnal CIS (
B
= 0.411;
p
= 7.7e − 6,
R
2
= 0.139) were detected. Thirty per cent of the subjects reported a moderate to severe negative impact of sialorrhea on their quality of life.
Conclusions
The present study suggests that CIS is highly prevalent in patients with schizophrenia and has an important impact on quality of life in one-third of our sample. Therefore, the inclusion of a systematic evaluation and treatment of CIS in standard clinical practice is highly recommended.
Trial registration
Clinical Trials (
https://clinicaltrials.gov
) under reference NCT04197037.
Precise regulation of transcription in gene expression is critical for all aspects of normal organism form, fitness, and function and even minor alterations in the level, location, and timing of gene ...expression can result in phenotypic variation within and between species including evolutionary innovations and human disease states. Eukaryotic transcription is regulated by a complex interplay of multiple factors working both at a physical and molecular levels influencing this process. In Saccharomyces cerevisiae, the TF with the greatest number of putative regulatory targets is the essential gene Repressor Activator Protein 1 (RAP1). While much is known about the roles of Rap1 in gene regulation and numerous cellular processes, the response of Rap1 target genes to systematic titration of RAP1 expression level remains unknown. To fill this knowledge gap, we used a strain with a tetracycline-titratable promoter replacing wild-type regulatory sequences of RAP1 to systematically reduce the expression level of RAP1 and followed this with RNA sequencing (RNA-seq) to measure genome-wide gene expression responses. Previous research indicated that Rap1 plays a significant regulatory role in particular groups of genes including telomere-proximal genes, homothallic mating (HM) loci, glycolytic genes, DNA repair genes, and ribosomal protein genes; therefore, we focused our analyses on these groups and downstream targets to determine how they respond to reductions in RAP1 expression level. Overall, despite being known as both an activator and as a repressor of its target genes, we found that Rap1 acts as an activator for more target genes than as a repressor. Additionally, we found that Rap1 functions as an activator of ribosomal protein genes and a repressor for HM loci genes consistent with predictions from the literature. Unexpectedly, we found that Rap1 functions as a repressor of glycolytic enzyme genes contrary to prior reports of it having the opposite effect. We also compared the expression of RAP1 to five different genes related to DNA repair pathway and found that decreasing RAP1 downregulated four of those five genes. Finally, we found no effect of RAP1 depletion on telomere-proximal genes despite its functioning to silence telomeric repeat-containing RNAs. Together our results enrich our understanding of this important transcriptional regulator.
•Yeast RAP1 acts predominantly as an activator of gene expression•RAP1 functions as an activator of ribosomal protein genes and RNR genes•RAP1 functions as a repressor of glycolysis genes and the homothallic mating loci•We did not find a consistent role of RAP1 in regulating telomere-proximal genes
Theoretical framework--We re-examine the results of Navas et al. (2020). The idea behind this is the theory of Harry Markowitz (1959, 2010), regarded as the founder of modern portfolio theory. ...Practical & social implications of research--To predict the composition of the portfolios, we do not take into consideration the crash of gold and precious metals in 2013.
Being an intense and pure source of low energy electron antineutrinos, nuclear reactors are one of the most powerful tools to investigate neutrino oscillations. The Double Chooz experiment aims for a ...precise determination of the neutrino mixing angle θ13 using a two detector configuration with a liquid scintillator target volume read by photomultipliers. The antineutrino detection efficiency systematic uncertainty is the dominant component in the normalization uncertainty affecting the final precision on the θ13 measurement.The collected data from the near detector since January 2015 will profit from improved detection systematic uncertainties thanks to the cancellation of correlated contributions between both detectors.
Magnetic nanostructures have been widely studied due to its poten¬tial applicability into several research fields such as data storage, sensing and biomedical applications. In this work, ...micromagnetic simulations (mumax3) of sub-micron iron discs are performed for different normalized inter-dot distance (distance/diameter), to better understand the magnetic behaviour of these nanos-tructures. Two sets of samples were studied: ideal circular discs and disc-shaped nanostructures (based on images of real samples). By analyzing the nucleation and annihilation fields and the magnetic susceptibility, it was found that the (ideal) discs could be considered as isolated for inter-dot distances greater than twice the raidus of the disc (2
R
). The difference in the shape of the disc-shaped nanostructures resulted in an in-plane anisotropy, noticeable on the hysteresis loops for different directions.
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