How Does Transverse MHD Wave-driven Turbulence Influence the Density Filling Factor in the Solar Corona?

It is well established that transverse MHD waves are ubiquitous in the solar corona. One of the possible mechanisms for heating both open (e.g., coronal holes) and closed (e.g., coronal loops) magnetic field regions of the solar corona is MHD wave-driven turbulence. In this work, we study the variation of the filling factor of overdense structures in the solar corona due to the generation of transverse MHD wave-driven turbulence. Using 3D MHD simulations, we estimate the density filling factor of an open magnetic structure by calculating the fraction of the volume occupied by the overdense plasma structures relative to the entire volume of the simulation domain. Next, we perform forward modeling and generate synthetic spectra of Fe xiii 10749 Å and 10800 Å density-sensitive line pairs using FoMo. Using the synthetic images, we again estimate the filling factors. The estimated filling factors obtained from both methods are in reasonable agreement. Also, our results match fairly well with the observations of filling factors in coronal holes and loops. Our results show that the generation of turbulence increases the filling factor of the solar corona.

Post-weaning Social Isolated Flinders Sensitive Line Rats Display Bio-Behavioural Manifestations Resistant to Fluoxetine: A Model of Treatment-Resistant Depression

Treatment-resistant depression (TRD) complicates the management of major depression (MD). The underlying biology of TRD involves interplay between genetic propensity and chronic and/or early life adversity. By combining a genetic animal model of MD and post-weaning social isolation rearing (SIR), we sought to produce an animal that displays more severe depressive- and social anxiety-like manifestations resistant to standard antidepressant treatment. Flinders Sensitive Line (FSL) pups were social or isolation reared from weaning [postnatal day (PND) 21], receiving fluoxetine (FLX) from PND 63 (10 mg/kg × 14 days), and compared to Sprague Dawley (SD) controls. Depressive-, anxiety-like, and social behaviour were assessed from PND 72 in the forced swim test (FST) and social interaction test (SIT). Post-mortem cortico-hippocampal norepinephrine (NE), serotonin (5-HT), and dopamine (DA), as well as plasma interleukin 6 (IL-6), tumour necrosis factor alpha (TNF-α), corticosterone (CORT), and dopamine-beta-hydroxylase (DBH) levels were assayed. FSL rats displayed significant cortico-hippocampal monoamine disturbances, and depressive- and social anxiety-like behaviour, the latter two reversed by FLX. SIR-exposed FSL rats exhibited significant immobility in the FST and social impairment which were, respectively, worsened by or resistant to FLX. In SIR-exposed FSL rats, FLX significantly raised depleted NE and 5-HT, significantly decreased DBH and caused a large effect size increase in DA and decrease in CORT and TNF-α. Concluding, SIR-exposed FSL rats display depressive- and social anxiety-like symptoms that are resistant to, or worsened by, FLX, with reduced plasma DBH and suppressed cortico-hippocampal 5-HT, NE and DA, all variably altered by FLX. Exposure of a genetic animal model of MD to post-weaning SIR results in a more intractable depressive-like phenotype as well as changes in TRD-related biomarkers, that are resistant to traditional antidepressant treatment. Given the relative absence of validated animal models of TRD, these findings are especially promising and warrant study, especially further predictive validation.

Faecal microbiota transplantation from patients with depression or healthy individuals into rats modulates mood-related behaviour

Differences in gut microbiota composition have been observed in patients with major depressive disorder (MDD) compared to healthy individuals. Here, we investigated if faecal microbiota transplantation (FMT) from patients with MDD into rats could induce a depressive-like phenotype. We performed FMT from patients with MDD (FMT-MDD) and healthy individuals (FMT-Healthy) into male Flinders Sensitive Line (FSL) and Flinders Resistant Line (FRL) rats and assessed depressive-like behaviour. No behavioural differences were observed in the FSL rats. In FRL rats, the FMT-Healthy group displayed significantly less depressive-like behaviour than the FMT-MDD group. However, there was no difference in behaviour between FMT-MDD FRL rats and negative controls, indicating that FMT-Healthy FRL rats received beneficial bacteria. We additionally found different taxa between the FMT-MDD and the FMT-Healthy FRL rats, which could be traced to the donors. Four taxa, three belonging to the family Ruminococcaceae and the genus Lachnospira, were significantly elevated in relative abundance in FMT-MDD rats, while the genus Coprococcus was depleted. In this study, the FMT-MDD group was different from the FMT-Healthy group based on behaviour and intestinal taxa.

De la cognition incarnée au corps cognitivisé

"From Embodied Cognition to the Cognitivised Body. The construction of meaning, before being a linguistic or neuronal phenomenon, is a sensitive phenomenon, indebted to the bodily experience of the world, the lived body. Varela’s neurophenomenological approach, which is inspired by the intertwining of the subject and the world as proposed by Merleau-Ponty, can only take in charge an ordinary production of meaning. What about when one produces a concept or a work of art? In other words, how does the body-mind relationship function in the act of creation? If the construction of meaning starts from the subject, in the sense that it is the subject who by his embodied cognitive activity produces meaning, the construction of a concept or a work of art solicits a super-personal force that engenders the subject himself: a heccéité, in the sense of Deleuze. What does this engendering of the subject mean and how does it intervene in the act of creation? In other words, why must the subject be somehow “recreated” in order to create? It is only when thought is destabilized by a point of crisis that it becomes a creative device that plays out between the chaotic intensities from which it tears itself away and the composition of a consistency. The starting point of the creative thought is the stopping of the thought and its continuation on another plane: a thought that leaves the field of cognition and recognition and derails, carried away by a sensitive line of flight, produced in the body, towards the inorganic and impersonal plane of a super-personal power. With the act of creation, the embodied cognition swings towards a de-subjectivation: the cognition becomes then a “chaognition”, an impersonal faculty mobilizing the power of passivity. Keywords: cognition, embodiment, subject, meaning, creation, heccéité, de-subjectivation. "

Potency and preclinical evidence of synergy of oral azole drugs and miltefosine in an ex vivo model of Leishmania (Viannia) panamensis infection

Failure of treatment of cutaneous leishmaniasis with antimonial drugs and miltefosine is frequent. Use of oral combination therapy represents an attractive strategy to increase efficacy of treatment and reduce the risk of drug resistance. We evaluated the potency of posaconazole, itraconazole, voriconazole and fluconazole, and the potential synergy of those demonstrating the highest potency, in combination with miltefosine (HePC), against infection with Leishmania (Viannia) panamensis . Synergistic activity was determined by isobolograms and calculation of Fractional Inhibitory Concentration Index (FICI), based on parasite quantification using an ex vivo model of human PBMCs infected with a luciferase-transfected, antimony and miltefosine sensitive line of L. panamensis . The drug combination and concentrations that displayed synergy were then evaluated for anti-leishmanial effect in 10 clinical strains of L. panamensis by qRT-PCR of Leishmania 7SLRNA. High potency was substantiated for posaconazole and itraconazole against sensitive as well as HePC and antimony resistant lines of L. panamensis , whereas fluconazole and voriconazole displayed low potency. HePC combined with posaconazole (Poz) demonstrated evidence of synergy at free drug concentrations achieved in plasma during treatment (2 μM HePC + 4 μM Poz). FICI, based on 70% and 90% reduction of infection, was 0.5 for the sensitive line. Combination of 2 μM HePC + 4 μM Poz effected significantly greater reduction of infection by clinical strains of L. panamensis than individual drugs. Orally administrable miltefosine/posaconazole combinations demonstrated synergistic anti-leishmanial capacity ex vivo against L. panamensis , supporting their potential as a novel therapeutic strategy to improve efficacy, and effectiveness of treatment.

Sirtuins and Neuropeptide y downregulation in Flinders Sensitive Line Rat Model of Depression

Objective: Since the NAD+-dependent histone deacetylases sirtuin-1 (SIRT1) and sirtuin-2 (SIRT2) are critically involved in epigenetics, endocrinology and immunology and affect the longevity in model organisms, we investigated their expression in brains of 3 month old and 14-15 month old rat model of depression Flinders Sensitive Line (FSL) and control Flinders Resistant Line (FRL) rats. In view of the dysregulated NPY system in depression we also studied NPY in young and old FSL to explore the temporal trajectory of depressive-like-ageing interaction. Methods: Sirt1, Sirt2 and Npy mRNA were determined using qRT-PCR in prefrontal cortex (PFC) from young and old FSL and FRL, and in hippocampi from young FSL and FRL. Results: PFC. Sirt1 expression was decreased in FSL (p=0.001). An interaction between age and genotype was found (p=0.032); young FSL had lower Sirt1 with respect to both age (p=0.026) and genotype (p=0.001). Sirt2 was lower in FSL (p=0.003). Npy mRNA was downregulated in FSL (p=0.001) but did not differ between the young and old rat groups. Hippocampus.Sirt1 was reduced in young FSL compared to young FRL (p=0.005). There was no difference in Sirt2 between FSL and FRL. Npy levels were decreased in hippocampus of young FSL compared to young FRL (p=0.003). Effects of ageing could not be investigated due to loss of samples. Conclusions: i. This is the first demonstration that SIRT1 and SIRT2 are changed in brain of FSL, a rat model of depression ; ii. The changes are age dependent; iii. Sirtuins are potential targets for treatment of age-related neurodegenerative diseases.

Uncovering the transcriptional response of popcorn (Zea mays L. var. everta) under long-term aluminum toxicity

To date, the investigation of genes involved in Al resistance has focused mainly on microarrays and short periods of Al exposure. We investigated genes involved in the global response under Al stress by tracking the expression profile of two inbred popcorn lines with different Al sensitivity during 72 h of Al stress. A total of 1003 differentially expressed genes were identified in the Al-sensitive line, and 1751 were identified in the Al-resistant line, of which 273 were shared in both lines. Genes in the category of “response to abiotic stress” were present in both lines, but there was a higher number in the Al-resistant line. Transcription factors, genes involved in fatty acid biosynthesis, and genes involved in cell wall modifications were also detected. In the Al-resistant line, GST6 was identified as one of the key hub genes by co-expression network analysis, and ABC6 may play a role in the downstream regulation of CASP-like 5. In addition, we suggest a class of SWEET transporters that might be involved in the regulation of vacuolar sugar storage and may serve as mechanisms for Al resistance. The results and conclusions expand our understanding of the complex mechanisms involved in Al toxicity and provide a platform for future functional analyses and genomic studies of Al stress in popcorn.

Identification of proteins in sensitive and tolerant lines of sunflower (Helianthus annus L.) under water deficit

<p>The importance of examining environmental stresses and their role in predicting and evaluating the growth and yield of crops is very evident. Environmental stresses are the most important factor in reducing agricultural yields worldwide. In order to evaluate the environmental impact of water loss on the amount of proteins affected in sunflower, an experiment was conducted in randomized complete block design with three replications at Karaj Oil Seeds Research Institute. In order to study the response of susceptible line (BGK221) and tolerant line (RGK46) under drought stress conditions, extraction of protein by acetone deposition method was performed in 8 leaves and of 3 seedlings in each replication. The amount of extracted protein was determined by Bradford method using two-dimensional electrophoresis and existence of significant difference between the bands in sensitive and tolerant lines was investigated. A total of 467 repeatable bands were found in the tolerant line and 417 repeatable bands appeared in the sensitive line. Among these proteins, 6 bands in tolerant line (No 503, 1901, 904, 3301, 7011, 9005) and 6 bands in sensitive line (No 704, 811, 3205, 4108, 7307, and 9207) were significantly affected by drought stress. In both sensitive and tolerate lines the main consequence is increase in amount of protein. The results showed that the most important factor of tolerant line adaptive for environmental stress conditions is maintaining normal cell metabolism, keeping moisture in the cell, strengthening cellular structure and antioxidant defense. The study also showed that drought stress had the greatest effect on cytoplasmic and nucleus proteins, metabolism and energy of proteins</p>