Low optical polarisation at the core of the optically-thin jet of M87

We study the optical linear and circular polarisation in the optically-thin regime of the core and jet of M87. Observations were acquired two days before the Event Horizon Telescope (EHT) campaign in early April 2017. A high degree ($\sim 20$ per cent) of linear polarisation (P$_{\rm lin}$) is detected in the bright jet knots resolved at $\sim 10\, \rm{arcsec}$ to $23\, \rm{arcsec}$ ($0.8$-$1.8\, \rm{kpc}$) from the centre, whereas the nucleus and inner jet show P$_{\rm lin} \lesssim 5$ per cent. The position angle of the linear polarisation shifts by $\sim 90$ degrees from each knot to the adjacent ones, with the core angle perpendicular to the first knot. The nucleus was in a low level of activity (P$_{\rm lin} \sim 2$-$3$ per cent), and no emission was detected from HST-1. No circular polarisation was detected either in the nucleus or the jet above a $3\sigma$ level of P$_{\rm circ} \leq 1.5$ per cent, discarding the conversion of P$_{\rm lin}$ into P$_{\rm circ}$. A disordered magnetic field configuration or a mix of unresolved knots polarised along axes with different orientations could explain the low P$_{\rm lin}$. The latter implies a smaller size of the core knots, in line with current interferometric observations. Polarimetry with EHT can probe this scenario in the future. A steep increase of both P$_{\rm lin}$ and P$_{\rm circ}$ with increasing frequency is expected for the optically-thin domain, above the turnover point. This work describes the methodology to recover the four Stokes parameters using a $\lambda/4$ wave-plate polarimeter.Comment: Accepted for publication in MNRAS. 10 pages, 8 figure

Amino acids in the development of Prodrugs

Although drugs currently used for the various types of diseases (e.g., antiparasitic, antiviral, antibacterial, etc.) are effective, they present several undesirable pharmacological and pharmaceutical properties. Most of the drugs have low bioavailability, lack of sensitivity, and do not target only the damaged cells, thus also affecting normal cells. Moreover, there is the risk of developing resistance against drugs upon chronic treatment. Consequently, their potential clinical applications might be limited and therefore, it is mandatory to find strategies that improve those properties of therapeutic agents. The development of prodrugs using amino acids as moieties has resulted in improvements in several properties, namely increased bioavailability, decreased toxicity of the parent drug, accurate delivery to target tissues or organs, and prevention of fast metabolism. Herein, we provide an overview of models currently in use of prodrug design with amino acids. Furthermore, we review the challenges related to the permeability of poorly absorbed drugs and transport and deliver on target organs.NV acknowledges support from Fundação para a Ciência e Tecnologia (FCT, Lisbon, Portugal) and FEDER (European Union), award number IF/00092/2014/CP1255/CT0004. NV also thanks FCT for the IF position and Fundação Manuel António da Mota (FMAM, Porto, Portugal) and Pfizer (Portugal) for support for the Nuno Vale Research Group. The contents of this report are solely the responsibility of the authors and do not necessarily represent the official views of the FCT, FMAM and Pfizer

Infrared Absorption Spectra of Nitric Acid and Its Solutions

Infrared spectra of reactive liquids such as anhydrous nitric and sulfuric acids were determined using silver chloride windows and, in some cases, Teflon spacers. The absorption frequencies of nitric acid agree well with those found from Raman spectra. A nitronium ion frequency was observed at 2360 cm^(-1). The intensity of this band is enhanced by the addition of nitronium fluoborate, sulfuric acid, phosphorous pentoxide, or small amounts of acetic anhydride. It is reduced by addition of sodium nitrate, potassium dihydrogen phosphate, water, or larger amounts of acetic anhydride. Its behavior in these media provides information about pertinent equilibria. A nitronium ion combination band was observed near 3745 cm^(-1) when the concentration of this ion was particularly large. Bands arising from unionized nitric acid are completely absent when a small amount of nitric acid is added to 100% H_2SO_4. Various bands found in aqueous nitric acid solutions are attributed to hydrogen‐bonded structures, both because of their behavior in different media and by analogy with effects observed in Raman studies

Fibulin-1 is required for morphogenesis of neural crest-derived structures

AbstractHere we report that mouse embryos homozygous for a gene trap insertion in the fibulin-1 (Fbln1) gene are deficient in Fbln1 and exhibit cardiac ventricular wall thinning and ventricular septal defects with double outlet right ventricle or overriding aorta. Fbln1 nulls also display anomalies of aortic arch arteries, hypoplasia of the thymus and thyroid, underdeveloped skull bones, malformations of cranial nerves and hemorrhagic blood vessels in the head and neck. The spectrum of malformations is consistent with Fbln1 influencing neural crest cell (NCC)-dependent development of these tissues. This is supported by evidence that Fbln1 expression is associated with streams of cranial NCCs migrating adjacent to rhombomeres 2–7 and that Fbln1-deficient embryos display patterning anomalies of NCCs forming cranial nerves IX and X, which derive from rhombomeres 6 and 7. Additionally, Fbln1-deficient embryos show increased apoptosis in areas populated by NCCs derived from rhombomeres 4, 6 and 7. Based on these findings, it is concluded that Fbln1 is required for the directed migration and survival of cranial NCCs contributing to the development of pharyngeal glands, craniofacial skeleton, cranial nerves, aortic arch arteries, cardiac outflow tract and cephalic blood vessels

The systematicity challenge to anti-representational dynamicism

After more than twenty years of representational debate in the cognitive sciences, anti-representational dynamicism may be seen as offering a rival and radically new kind of explanation of systematicity phenomena. In this paper, I argue that, on the contrary, anti-representational dynamicism must face a version of the old systematicity challenge: either it does not explain systematicity, or else, it is just an implementation of representational theories. To show this, I present a purely behavioral and representation-free account of systematicity. I then consider a case of insect sensorimotor systematic behavior: communicating behavior in honey bees. I conclude that anti-representational dynamicism fails to capture the fundamental trait of systematic behaviors qua systematic, i.e., their involving exercises of the same behavioral capacities. I suggest, finally, a collaborative strategy in pursuit of a rich and powerful account of this central phenomenon of high cognition at all levels of explanation, including the representational level

The effects of cognitive-behavioural therapy on mood-related ruminative response style in depressed adolescents

<p>Abstract</p> <p>Background</p> <p>A mood-related ruminative response style increases the risk of onset and persistence of depression. This preliminary study investigated whether, in depressed adolescents, cognitive-behaviour therapy reduces mood-related ruminative response style. Whether specific factors within the rumination scale were differentially affected by CBT is also reported.</p> <p>Methods</p> <p>26 depressed adolescents were randomised to receiving serotonin-specific reuptake inhibitor antidepressants (SSRI) plus psychosocial treatment as usual or SSRI and psychosocial treatment as usual plus CBT. Ruminative response style and depressive symptoms were measured at baseline and after 30 weeks of treatment, with the Responses to Depression Questionnaire and Mood and Feelings Questionnaire.</p> <p>Results</p> <p>There were significantly greater reductions in ruminations in the CBT group compared to the non-CBT group (<it>p </it>= .002). There was no significant difference in the reduction in self-reported depressive symptoms between the groups. Rumination was reduced to levels of never-depressed controls in adolescents who had recovered from depression and received CBT. There were greater falls in the CBT group in the more pathological 'brooding' factor of rumination.</p> <p>Conclusion</p> <p>These findings suggest that adding CBT to SSRI medication in the presence of active clinical care causes a greater reduction in mood-related ruminative response style in depressed adolescents. This may reduce the risk of future relapse.</p> <p>Trial registration</p> <p>Current Controlled Trials ISRCNT83809224.</p

Two serological approaches for detection of antibodies to SARS-CoV-2 in different scenarios: a screening tool and a point-of-care test

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected more than 8 million people worldwide, becoming a pandemic. Detecting antibodies against SARS-CoV-2 is of utmost importance and a good indicator of exposure and circulation of the virus within the general population. Two serological tools based on a double recognition assay [enzyme-linked immunosorbent assay (DR-ELISA) and lateral flow assay (DR-LFA)] to detect total antibodies to SARS-CoV-2 have been developed based on the recombinant nucleocapsid protein. A total of 1065 serum samples, including positive for COVID-19 and negative samples from healthy donors or infected with other respiratory pathogens, were analyzed. The results showed values of sensitivity between 91.2% and 100%, and specificity of 100% and 98.2% for DR-LFA and DR-ELISA, respectively. No cross-reactivity against seasonal coronavirus (HCoV-NL63, HCoV-229E, HCoV-HKU1, HCoV-OC43) was found. These results demonstrate the importance of serology as a complementary tool to polymerase chain reaction for follow-up of recovered patients and identification of asymptomatic individuals