Hundreds of Low-Mass Active Galaxies in the Galaxy And Mass Assembly (GAMA) Survey

We present an entirely new sample of 388 low-mass galaxies ($M_\star \leq 10^{10} M_\odot$) that have spectroscopic signatures indicating the presence of massive black holes (BHs) in the form of active galactic nuclei (AGNs) or tidal disruption events (TDEs). Of these, 70 have stellar masses in the dwarf galaxy regime with $10^8 \lesssim M_\star/M_\odot \lesssim 10^{9.5}$. We identify the active galaxies by analyzing optical spectra of a parent sample of $\sim$23,000 low-mass emission-line galaxies in the Galaxy and Mass Assembly (GAMA) Survey Data Release 4, and employing four different diagnostics based on narrow emission line ratios and the detection of high-ionization coronal lines. We find that 47 of the 388 low-mass active galaxies exhibit broad H$\alpha$ in their spectra, corresponding to virial BH masses in the range $M_{\rm BH} \sim 10^{5.0-7.7} M_\odot$ with a median BH mass of $\langle M_{\rm BH}\rangle \sim 10^{6.2} M_\odot$. Our sample extends to higher redshifts ($z \le 0.3; \langle z \rangle=0.13$) than previous samples of AGNs in low-mass/dwarf galaxies based on Sloan Digital Sky Survey spectroscopy, which can be attributed to the spectroscopic limit of GAMA being $\sim 2$ magnitudes deeper. Moreover, our multi-diagnostic approach has revealed low-mass active galaxies spanning a wide range of properties, from blue star-forming dwarfs to luminous "miniquasars" powered by low-mass BHs. As such, this work has implications for BH seeding and AGN feedback at low masses.Comment: Accepted for publication in The Astrophysical Journa

Evaluation of Tear Function among Acne Vulgaris Patients Undergoing Treatment with Isotretinoin

Purpose: To evaluate the effect of Isotretinoin on tear secretion among patients with Acne Vulgaris.Patients and Methods: In this prospective study patients candidate for isotretinoin (Accutane) therapy for two months underwent complete eye examination. The best corrected visual acuity was measures and slit lamp examination of anterior segment, evaluation of tear break-up-time and Schirmer’s test were performed. The post surgical examination carried out two months post therapy consisted of complete eye examination and evaluation of dry eye level.Findings: Thirty nine patients entered the study. There were 5 patients complaining of eye strain before treatment, which rose to 19 patients after Isotretinoin therapy (p<0.001). The tear break up time was 13±1 seconds which decreased to 9±1 (p<0.001) after therapy and the Schirmer’s test mean reading was 22±2mm, which was reduced to 18±5 (p<0.001) after treatment. There were 4 patients with blepharitis before the treatment which rose to 19 patients after the end of Isotretinoin treatment (p<0.001).Conclusion: Isotretinoin usage (0.5-1mg/kg for two months) impairs the tear secretion and causes dry eye and blepharitis among patients. Considering the young age of patients using this drug, some of them candidates for keratorefractive surgery, a history of Isotretinoin usage should be considered before commencing the surgery. We recommend postponing the refractive surgery among these patients until the signs of dry eye are subsided.

Survival of COVID-19 patients requires precise immune regulation: The hypothetical immunoprotective role of nicotinic agonists

Summary recent studies have provided novel evidence regarding the effect of nicotine agonists on the prevention or modulation of cytokines storm and reduction of infection. In this study we tried to attempt to address these issues from a therapeutic perspective of nicotine agonists in this manner and we describe one of the most challenging theories of immunotherapy in coronavirus-19 (COVID-19). The analysis of the proposed mechanism goes beyond the physiological consequences of a way to design new strategies to provide anti-inflammatory drugs. © 2020 Elsevier Lt

Room temperature methoxylation in zeolites: insight into a key step of the methanol-to-hydrocarbons process

Neutron scattering methods observed complete room temperature conversion of methanol to framework methoxy in a commercial sample of methanol-to-hydrocarbons (MTH) catalyst H-ZSM-5, evidenced by methanol immobility and vibrational spectra matched by ab initio calculations. No methoxylation was observed in a commercial HY sample, attributed to the dealumination involved in high silica HY synthesis

Efficiency analysis of primary wood producers in British Columbia using data envelopment analysis

The Canadian wood industry has faced several changes during the last decade. These changes include increasing global competition, changes in macro and micro practices, market restructuring, and technological advancements. One of the most affected sectors by these changes in the business environment is the primary wood manufacturing sector in British Columbia. This study examines the performance of this sector over the period of 1990-2002. The base methodological approach used is Data Envelopment Analysis. The study has two major objectives: first, to evaluate the efficiency of BC primary wood producers in 2002 and in relation to some environmental and managerial factors. Second, to analyze the efficiency trend of BC primary wood producers during the 1990-2002 period and identify the underlying causes. The first part of the study reveals some technical inefficiencies for the BC primary wood sector, but predominantly high scale efficiencies. Technical efficiency may be improved by increasing lumber and chip production, as well as enhancing the labour productivity. BC forest regions were significantly different in terms of efficiency; the northern interior regions showed the highest efficiency, followed by the regions in the southern interior. The coastal forest regions had the lowest efficiency. The second part of the study suggests a productivity decline in 1991 for the sector, followed by a steady state until 1996 when continuous growth began. The major reason for the productivity growth was technological advancement rather than technical efficiency improvement. The analysis of the mills which were shut down in 2002, demonstrated that most of them had been performing below average provincial efficiency levels, either due to lack of technical capabilities or the scale of operations.Forestry, Faculty ofGraduat

Effect of diluted and preheated oxidizer on the emission of methane flameless combustion

In combustion process, reduction of emissions often accompanies with output efficiency reduction. It means, by using current combustion technique it is difficult to obtainlow pollution and high level of efficiency in the same time. In new combustion system, low NOxengines and burners are studied particularly. Recently flameless or Moderate and Intensive Low oxygen Dilution (MILD) combustion has received special attention in terms of low harmful emissions and low energy consumption. Behavior of combustion with highly preheated air was analyzed to study the change of combustion regime and the reason for the compatibility of high performance and low NOx production. Sustainability of combustion under low oxygen concentration was examined when; the combustion air temperature was above the self-ignition temperature of the fuel. This paper purposes to analyze the NOx emission quantity in conventional combustion and flameless combustion by Chemical Equilibrium with Applications (CEA) software

Clinical Features and Outcomes of Strabismus Treatment in Third Cranial Nerve Palsy during a 10-Year Period

Purpose: To evaluate the demographics and management outcomes of strabismus surgery in patients with third cranial nerve palsy. Methods: This retrospective study includes subjects with third cranial nerve palsy. We evaluated age, sex, laterality, severity of involvement, etiology, frequency of clinical findings, and types and results of treatments. Results: 52 patients including 29 male and 23 female subjects with mean age of 21.1±15.5 years were studied between January 1999 and January 2009. Etiologies of third nerve palsy included congenital in 16 (30.8%), trauma in 26 (50%) and other causes in 10 (19.2%) patients. In 24 patients (46.2%), the palsy was complete. The most common type of strabismus was exotropia associated with hypotropia (40%). Medical treatment was used in 25 (48%) and surgical treatment in 46 (88.4%) subjects. One time strabismus surgery was performed in 30 (65.2%), 2 times in 11 (24%) and 3 times in 5 (10.8%) subjects. The most common operation was large horizontal recession and resection in 78.2% of cases. Mean horizontal deviation in primary position was 66±29 prism diopters (PD) before surgery decreasing to 21±19, 13±12 and 6±8 PD after first, second and third surgery, respectively. Corresponding figures for mean vertical deviation were 13±15, 7±12, 4±6 and 1±2 PD, respectively. Abnormal head posture was 10-30° in 11 (21.1%) cases before treatment which completely resolved after surgery. Conclusion: Surgical management of strabismus in patients with third nerve palsy is difficult and challenging, however the majority of patients achieve ideal results with appropriate and stepwise surgical plans

Environmental protection and fuel consumption reduction by flameless combustion technology: A review

In recent years global fuel consumption has increasedin the world due to modernization and progress in the standard of living. The conspicuous rate of carbon dioxide and nitrogen oxide released to the environment and fuel resources are depleted day by day due toinconsiderate fuel consumption. Requirement for efficient use of any kinds of fuel has become the other concern due to the oil crisis and limitation of fuel resources. In combustion process, the abatement of pollutants often associates with efficiency loss. In the other word, high efficiency and low pollutant which are the main requirements of combustion are not fulfilled by the existing combustion. Today, flameless combustion has received more attention because of its low NOx emission and significant energy saving. Generally, compatibility between high performance and low NOx emission has been observed by preheated air application and changing the combustion characteristics from traditional flame to flameless mode. This paper aims to review the concepts and the applications of flameless combustion and gathers useful information to understand the necessity of transient from traditional flame mode to flameless combustion. © (2013) Trans Tech Publications, Switzerland