13 research outputs found
Parsec-scale structure of quasars: dawn of the golden age?
No full textHalf a century after their discovery, the study of quasars remains one of the most fascinating intellectual challenges in astronomy. Quasars are laboratories for everything from relativity to magnetohydrodynamics and are perhaps the best available probes for cosmology. A tremendous amount has been learned about quasars and yet many of the most fundamental questions about their physics remain open. Parsec-scale observations have played an indispensable role in building up our current understanding of quasars; virtually everything we know about quasars depends on such observations. However, the finest hour for parsec scale observations may be just beginning. This is partly due to the development of highly reliable VLBI networks (which is continuing) but mostly due to the unprecedented availability of multiepoch, simultaneous, broadband observations that have long been the `holy grail' for quasar researchers.The author gratefully acknowledges his colleagues in the TANAMI and Fermi/LAT programs from whom he continues to learn. The author sincerely apologizes for the vast range of wonderful work that he was unable to touch upon in such a brief review. This research was funded in part by NASA through Fermi Guest Investigator grant NNH10ZDA001N (proposal number 41213). This research was supported by an appointment to the NASA Postdoctoral Program at the Goddard Space Flight Center, administered by Oak Ridge Associated Universities through a contract with NASA. This research has made use of NASA’s Astrophysics Data System. This research has made use of the NASA/IPAC Extragalactic Database (NED) which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. This research has made use of the SIMBAD database (operated at CDS, Strasbourg, France).https://arxiv.org/abs/1310.087
Neonatal blood gas sampling methods
No full textBlood gas sampling is part of everyday practice in the care of babies admitted to the neonatal intensive care unit, particularly for those receiving respiratory support. There is little published guidance that systematically evaluates the different methods of neonatal blood gas sampling, where each method has its individual benefits and risks. This review critically surveys the available evidence to generate a comparison between arterial and capillary blood gas sampling, focusing on their relative accuracy and complications, as well as briefly mentioning the management of such complications. This evidence-based summary and guidance should help inform best practice in the neonatal intensive care unit, and minimise the exposure of babies to unnecessary and potentially serious risk. The most accurate and non-invasive method of measuring oxygenation is oxygen saturation monitoring. Indwelling arterial catheters are a practical, reliable and accurate method of measuring acid-base parameters, provided they are inserted and maintained with the proper care. Capillary blood gas sampling is accurate, and a good substitute for radial 'stab' arterial puncture, avoiding many of the complications of repeated arterial puncture
Neonatal blood gas sampling methods
No full textBlood gas sampling is part of everyday practice in the care of babies admitted to the neonatal intensive care unit, particularly for those receiving respiratory support. There is little published guidance that systematically evaluates the different methods of neonatal blood gas sampling, where each method has its individual benefits and risks. This review critically surveys the available evidence to generate a comparison between arterial and capillary blood gas sampling, focusing on their relative accuracy and complications, as well as briefly mentioning the management of such complications. This evidence-based summary and guidance should help inform best practice in the neonatal intensive care unit, and minimise the exposure of babies to unnecessary and potentially serious risk. The most accurate and non-invasive method of measuring oxygenation is oxygen saturation monitoring. Indwelling arterial catheters are a practical, reliable and accurate method of measuring acid-base parameters, provided they are inserted and maintained with the proper care. Capillary blood gas sampling is accurate, and a good substitute for radial 'stab' arterial puncture, avoiding many of the complications of repeated arterial puncture
From Radio with Love: an overview of the role of radio observations in understanding high-energy emission from active galaxies
No full textThe gamma-ray satellite Fermi and the ground based TeV facilities MAGIC, VERITAS and HESS have ushered in a new era in the observation of high-energy emission from active galaxies. The energy budgets of these objects have a major contribution from gamma-rays and it is simply not possible to understand their physics without high-energy observations. Though the exact mechanisms for high-energy production in galaxies remains an open question, gamma-rays typically result from interactions between high-energy particles. Via different interactions these same particles can produce radio emission. Thus the non-thermal nature of gamma-ray emission practically guarantees that high-energy emitters are also radio loud. Aside from their obvious role as a component of multiwavelength analysis, radio observations provide two crucial elements essential to understanding the source structure and physical processes of high-energy emitters: very high timing resolution and very high spatial resolution. A brief overview of the unique role played by radio observations in unraveling the mysteries of the high energy Universe is presented here.The author thanks Matthias Kadler for numerous very helpful discussions. He also acknowledges the generous help and advice of Denise Gabuzda, Marco Giroletti, Dan Homan, Svetlana Jorstad, Alan Marscher and Greg Taylor. Responsibility for any shortcomings, however, lies solely with the author. This research was funded in part by NASA through Fermi Guest Investigator grant NNH09ZDA001N. This research was supported by an appointment to the NASA Postdoctoral Program at the Goddard Space Flight Center, administered by Oak Ridge Associated Universities through a contract with NASA.https://iopscience.iop.org/article/10.1088/1742-6596/355/1/01200
Characterization Of Mixed Gels
No full textThis Dissertation / Report is the outcome of investigation carried out by the creator(s) / author(s) at the department/division of Central Food Technological Research Institute (CFTRI), Mysore mentioned below in this page
Simulation of Forward Osmosis Using CFD
No full textAbstractIf fresh water and salt water are separated by a membrane, the fresh water would flow across the membrane from fresh water chamber to salt water chamber in a forward osmosis process. Forward osmosis and reverse osmosis processes have been used for many new applications like wastewater treatment, food processing industry, and desalination of seawater. Computational Fluid Dynamics (CFD) software, viz., FLUENT software is used for simulating FO process. The water moved across the membrane from fresh water side to salt water chamber indicating that FO was well represented by FLUENT
Method for Generation of Pendant Drops Through Localized Condensation for Contact Angle Measurements in Conditions Deviating from Standard Environment
No full textabstract: Contact angle goniometer is one of the most common tools in surfaces science. Since the introduction of this instrument by Fox and Zisman1 in 1950, dispensing the liquid using a syringe has generated pendant drops. However, using such approach at conditions significantly deviating from standard pressure and temperature would require an elaborate and costly fluidic system. To this end, this thesis work introduces alternative design of a goniometer capable of contact angle measurement at wide pressure and temperature range. In this design, pendant droplets are not dispensed through a pipette but are generated through localized condensation on a tip of a preferentially cooled small metal wire encapsulated within a thick thermal insulator layer. This thesis work covers experimental study of the relation between the geometry of the condensation-based pendant drop generator geometry and subcooling, and growth rate of drops of representative high (water) and low (pentane) surface tension liquids. Several routes that the generated pendant drops can be used to measure static and dynamic contact angles of the two liquids on common substrates well as nanoengineered superhydrophobic and omniphobic surfaces are demonstrated.Dissertation/ThesisMasters Thesis Mechanical Engineering 201
Author Correction: Sustained aviremia despite anti-retroviral therapy non-adherence in male children after in utero HIV transmission
No full textCorrection to: Nature Medicinehttps://doi.org/10.1038/s41591-024-03105-4, published online 6 June 2024. In the version of the article initially published, two of Javier Martinez-Picado’s affiliations (Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain and Infectious Diseases and Immunity Department, University of Vic-Central University of Catalonia, Vic, Spain) were missing and have now been added to the HTML and PDF versions of the article
Picture versus words: A comparison of pictorial and verbal informed assent formats
No full textBackground for the Study: Informed consent is a process of obtaining permission from the participant to participate in research. Involving children in a research requires them to give their “assent” for participation. Informed assent is obtained from children even after their guardians have given consent for participation. Studies have shown that children have difficulty understanding the key elements of research process such as right to withdraw from the study or the meaning of “harm” involved in the research process. Further, the studies have also propounded that using child-friendly methods such as using pictures and simple language would facilitate children's understanding. Objectives: In this study, pictorial and verbal assent formats were compared find out which format is suitable for children's understanding of informed assent with respect to research. Methods: A sample of 389 school going children and adolescents of both the gender, ranging from 7 to 16 years were considered for the study. The sample was randomly divided into two groups, where for one group (n = 197), pictorial assent format was administered and another group (n = 192), verbal assent format was administered. The pictorial assent format was developed for the study by the corresponding author. Results and Conclusions: Analysis revealed that there was a significant level of interaction between gender and the two assent formats. Males were able to understand pictorial assent format better compared to the females, whereas females were able to understand verbal assent format better than the males, when age and education were considered as covariates. Further, it was found that as age increases there is better understanding of research processes in both the formats. Hence, while the process of obtaining assent for participation in research, age of child must be considered and with respect to gender differences males tend to prefer pictorial formats whereas females tend to prefer verbal formats
Sustained aviremia despite anti-retroviral therapy non-adherence in male children after in utero HIV transmission
No full textAfter sporadic reports of post-treatment control of HIV in children who initiated combination anti-retroviral therapy (cART) early, we prospectively studied 284 very-early-cART-treated children from KwaZulu-Natal, South Africa, after vertical HIV transmission to assess control of viremia. Eighty-four percent of the children achieved aviremia on cART, but aviremia persisting to 36 or more months was observed in only 32%. We observed that male infants have lower baseline plasma viral loads (P = 0.01). Unexpectedly, a subset (n = 5) of males maintained aviremia despite unscheduled complete discontinuation of cART lasting 3-10 months (n = 4) or intermittent cART adherence during 17-month loss to follow-up (n = 1). We further observed, in vertically transmitted viruses, a negative correlation between type I interferon (IFN-I) resistance and viral replication capacity (VRC) (P < 0.0001) that was markedly stronger for males than for females (r = -0.51 versus r = -0.07 for IFN-alpha). Although viruses transmitted to male fetuses were more IFN-I sensitive and of higher VRC than those transmitted to females in the full cohort (P < 0.0001 and P = 0.0003, respectively), the viruses transmitted to the five males maintaining cART-free aviremia had significantly lower replication capacity (P < 0.0001). These data suggest that viremic control can occur in some infants with in utero-acquired HIV infection after early cART initiation and may be associated with innate immune sex differences
