Star formation and accretion in the circumnuclear disks of active galaxies

We explore the evolution of supermassive black holes (SMBH) centered in a circumnuclear disk (CND) as a function of the mass supply from the host galaxy and considering different star formation laws, which may give rise to a self-regulation via the injection of supernova-driven turbulence. A system of equations describing star formation, black hole accretion and angular momentum transport was solved for an axisymmetric disk in which the gravitational potential includes contributions from the black hole, the disk and the hosting galaxy. Our model extends the framework provided by Kawakatu et al. (2008) by separately considering the inner and outer part of the disk, and by introducing a potentially non-linear dependence of the star formation rate on the gas surface density and the turbulent velocity. The star formation recipes are calibrated using observational data for NGC 1097, while the accretion model is based on turbulent viscosity as a source of angular momentum transport in a thin viscous accretion disk. We find that current data provide no strong constraint on the star formation recipe, and can in particular not distinguish between models entirely regulated by the surface density, and models including a dependence on the turbulent velocity. The evolution of the black hole mass, on the other hand, strongly depends on the applied star formation law, as well as the mass supply from the host galaxy. We suggest to explore the star formation process in local AGN with high-resolution ALMA observations to break the degeneracy between different star formation models.Comment: 13 pages, 15 figures, 6 tables, accepted at A&

Enhancing laser sideband cooling in one-dimensional optical lattices via the dipole interaction

We study resolved sideband laser cooling of a one-dimensional optical lattice with one atom per site, and in particular the effect of the dipole interaction between radiating atoms. For simplicity, we consider the case where only a single cooling laser is applied. We derive a master equation, and solve it in the limit of a deep lattice and weak laser driving. We find that the dipole interaction significantly changes the final temperature of the particles, increasing it for some phonon wavevectors and decreasing it for others. The total phonon energy over all modes is typically higher than in the non-interacting case, but can be made lower by the right choice of parameters

Effect of Varying Dietary Selenium Levels on Tissue Composition, Blood Composition and Performance of Growing Swine Fed Seleniferous Grains

It is established that selenium is an essential micronutrient as well as a natural toxicant for domestic livestock. However, reports of selenium toxicosis in swine are limited and not well documented. The level at which selenium becomes toxic to swine is thought to be about 8 ppm. This value was derived from the initial selenium research of the 1930\u27s, with considerable extrapolation from other species used in this determination. Since that time, diet composition has become much more complex, nutrient level of diets has increased and feed additives are commonly used. It is not known what effect these factors or other nutritional interrelationships may have on the level at which selenium becomes toxic. Due to the variability of selenium content in feedstuffs and because selenium is now approved as a feed additive, it is important to better define the level at which selenium becomes toxic to swine. This research was conducted to determine the effect of varying dietary selenium levels on tissue and blood composition and performance of growing swine fed seleniferous grains

Advanced Magnetic Resonance Imaging in Glioblastoma: A Review

INTRODUCTION In 2017, it is estimated that 26,070 patients will be diagnosed with a malignant primary brain tumor in the United States, with more than half having the diagnosis of glioblas- toma (GBM).1 Magnetic resonance imaging (MRI) is a widely utilized examination in the diagnosis and post-treatment management of patients with glioblastoma; standard modalities available from any clinical MRI scanner, including T1, T2, T2-FLAIR, and T1-contrast-enhanced (T1CE) sequences, provide critical clinical information. In the last decade, advanced imaging modalities are increasingly utilized to further charac- terize glioblastomas. These include multi-parametric MRI sequences, such as dynamic contrast enhancement (DCE), dynamic susceptibility contrast (DSC), diffusion tensor imaging (DTI), functional imaging, and spectroscopy (MRS), to further characterize glioblastomas, and significant efforts are ongoing to implement these advanced imaging modalities into improved clinical workflows and personalized therapy approaches. A contemporary review of standard and advanced MR imaging in clinical neuro-oncologic practice is presented

EEG Source Imaging Indices of Cognitive Control Show Associations with Dopamine System Genes.

Cognitive or executive control is a critical mental ability, an important marker of mental illness, and among the most heritable of neurocognitive traits. Two candidate genes, catechol-O-methyltransferase (COMT) and DRD4, which both have a roles in the regulation of cortical dopamine, have been consistently associated with cognitive control. Here, we predicted that individuals with the COMT Met/Met allele would show improved response execution and inhibition as indexed by event-related potentials in a Go/NoGo task, while individuals with the DRD4 7-repeat allele would show impaired brain activity. We used independent component analysis (ICA) to separate brain source processes contributing to high-density EEG scalp signals recorded during the task. As expected, individuals with the DRD4 7-repeat polymorphism had reduced parietal P3 source and scalp responses to response (Go) compared to those without the 7-repeat. Contrary to our expectation, the COMT homozygous Met allele was associated with a smaller frontal P3 source and scalp response to response-inhibition (NoGo) stimuli, suggesting that while more dopamine in frontal cortical areas has advantages in some tasks, it may also compromise response inhibition function. An interaction effect emerged for P3 source responses to Go stimuli. These were reduced in those with both the 7-repeat DRD4 allele and either the COMT Val/Val or the Met/Met homozygous polymorphisms but not in those with the heterozygous Val/Met polymorphism. This epistatic interaction between DRD4 and COMT replicates findings that too little or too much dopamine impairs cognitive control. The anatomic and functional separated maximally independent cortical EEG sources proved more informative than scalp channel measures for genetic studies of brain function and thus better elucidate the complex mechanisms in psychiatric illness

Research notes: A possible cytoplasmic mutant

A chimera plant (A75-1165-117) was observed in 1975 in the F2 of a cross of Ames ms1 x \u27Clark\u27 homozygous translocation (Table 1). Reciprocal crosses were made with \u27Clark 63\u27, using branches from the chimera plant that contained a high percentage of yellow trifoliolates. Selfed seed of the chimera plant (A75-1165-117) and F1 seed from reciprocal crosses were planted in the field in 1976 (Table 2)

Pain Medicine Fellowship Program Websites in the United States of America - A Nonparametric Statistic Analysis of 14 Different Criteria

Objective: To evaluate the content of Pain Medicine Fellowship Program websites in the United States of America. Methods: We obtained a list of accredited 104 Pain Medicine Fellowship Program websites from the Accreditation Council for Graduate Medical Education and the Electronic Residency Application Service. Individual Pain Medicine Fellowship Program websites were then evaluated on 14 different criteria. We grouped fellowship programs based on census region and Electronic Residency Application Service participation status, and analyzed the differences using nonparametric statistics. Results: A total of 104 accredited Pain Medicine Fellowship Program websites were evaluated for a total of 14 different criteria. Of the 14 different criteria, an average of 3.94 were described in each website. Number of Fellowship positions per year (71.8%), clinical rotations during the program (65.1%), and faculty background (62.2%) were the most frequently described features on the websites. Night call responsibilities (3.9%), meal allowance (7.8%) and parking availability (10.7%) were the least described features in the websites. There were no significant differences between program websites when grouped by census regions or the participation status in the Electronic Residency Applications Service. Conclusion: The content of Pain Medicine Fellowship Program websites is extremely variable across the United States of America. This study indicates that there is room for improvement and enhancement of the comprehensiveness of website content for the majority of the programs analyzed. Additionally, this study also emphasizes the importance of having accurate and easily available online information in a post-pandemic era, when prospective fellows evaluate programs online through their websites.info:eu-repo/semantics/publishedVersio

Transformation of stimulus correlations by the retina

Redundancies and correlations in the responses of sensory neurons seem to waste neural resources but can carry cues about structured stimuli and may help the brain to correct for response errors. To assess how the retina negotiates this tradeoff, we measured simultaneous responses from populations of ganglion cells presented with natural and artificial stimuli that varied greatly in correlation structure. We found that pairwise correlations in the retinal output remained similar across stimuli with widely different spatio-temporal correlations including white noise and natural movies. Meanwhile, purely spatial correlations tended to increase correlations in the retinal response. Responding to more correlated stimuli, ganglion cells had faster temporal kernels and tended to have stronger surrounds. These properties of individual cells, along with gain changes that opposed changes in effective contrast at the ganglion cell input, largely explained the similarity of pairwise correlations across stimuli where receptive field measurements were possible.Comment: author list corrected in metadat