HI and OH absorption at z=0.89

We report on WSRT observations of HI and OH absorption at z=0.885 towards the radio lens PKS 1830-21, mm wave transitions of several molecular species have already been observed at this redshift. At mm wavelengths the source structure is dominated by two extremely compact components, the northeast (NE) and southwest (SW) components. At lower frequencies the continuum emission is much more extended and there is also a broad Einstein ring connecting the NE and SW components. This means that the HI and OH spectra sample a much larger region of the absorber than the mm wave spectra. The HI spectrum that we obtain is asymmetric, with a peak at -147 km/s with respect to the main molecular line redshift of z=0.88582. Weak mm wave molecular absorption has also been detected towards the NE component at this same velocity. The HI absorption, however, covers a total velocity width of 300 km/sec, i.e. including velocities well to the red of molecular features suggesting that it is spatially widespread. In OH we detect both the 1667 and the 1665 MHz transitions. The OH spectrum has a velocity width comparable to that of the HI spectrum, suggesting that it too is widespread in the absorber. The lack of a prominent HI peak in the spectrum at the velocity corresponding to the SW component, suggests that the galaxy responsible for the absorption at z=0.885 has a central molecular disk many kpc in size, and that HI is deficient in this central region. Our observations are sensitive to the large scale kinematics of the absorber, and to first order the implied dynamical mass is consistent with the lens models of Nair et. al. (1993).Comment: 4 pages, 3 figure

An architecture for object-oriented intelligent control of power systems in space

A control system for autonomous distribution and control of electrical power during space missions is being developed. This system should free the astronauts from localizing faults and reconfiguring loads if problems with the power distribution and generation components occur. The control system uses an object-oriented simulation model of the power system and first principle knowledge to detect, identify, and isolate faults. Each power system component is represented as a separate object with knowledge of its normal behavior. The reasoning process takes place at three different levels of abstraction: the Physical Component Model (PCM) level, the Electrical Equivalent Model (EEM) level, and the Functional System Model (FSM) level, with the PCM the lowest level of abstraction and the FSM the highest. At the EEM level the power system components are reasoned about as their electrical equivalents, e.g, a resistive load is thought of as a resistor. However, at the PCM level detailed knowledge about the component's specific characteristics is taken into account. The FSM level models the system at the subsystem level, a level appropriate for reconfiguration and scheduling. The control system operates in two modes, a reactive and a proactive mode, simultaneously. In the reactive mode the control system receives measurement data from the power system and compares these values with values determined through simulation to detect the existence of a fault. The nature of the fault is then identified through a model-based reasoning process using mainly the EEM. Compound component models are constructed at the EEM level and used in the fault identification process. In the proactive mode the reasoning takes place at the PCM level. Individual components determine their future health status using a physical model and measured historical data. In case changes in the health status seem imminent the component warns the control system about its impending failure. The fault isolation process uses the FSM level for its reasoning base

FLAGCAL:A flagging and calibration package for radio interferometric data

We describe a flagging and calibration pipeline intended for making quick look images from GMRT data. The package identifies and flags corrupted visibilities, computes calibration solutions and interpolates these onto the target source. These flagged calibrated visibilities can be directly imaged using any standard imaging package. The pipeline is written in "C" with the most compute intensive algorithms being parallelized using OpenMP.Comment: 15 Pages, 6 figures, 2 Tables, Accepted for publication in the Experimental Astronomy Journa

Stem Cell Based Therapies for Glaucoma

Glaucoma remains one of the leading causes of worldwide blindness. In England and Wales glaucoma is a major or contributory factor for 12-14% of all registrations for blindness and partial sight, second only to macular degeneration (Bunce et al., 2010). The worldwide burden is more significant, with glaucoma being the second leading cause of global blindness after cataract (Resnikoff et al., 2004). It has been estimated that 60.5 million people worldwide would be affected by glaucoma by 2010, with the figure expected to rise to 80 million by 2020 (Quigley and Broman, 2006). Current treatments for glaucoma comprise the lowering of intraocular pressure by eye drops, laser procedures or drainage surgery. However, as implied by the statistics above, many patients experience significant visual loss due to degeneration of retinal ganglion cells (RGCs) despite the advances in the treatments currently available. The need for novel therapies exists for such patients, in particular those with end stage glaucoma, where maintenance of a small number of surviving RGCs may yet permit a reasonable quality of life (Much et al., 2008). Stem cell therapies developed in the laboratory and translated to clinical practice provide an exciting and realistic hope for those affected by degenerative retinal diseases including glaucoma. This chapter will discuss three mechanisms by which stem cell therapies may potentially offer hope to patients with glaucoma, namely local retinal ganglion cell replacement, retina and optic nerve regeneration and stem cell mediated neuroprotection

Managing risk in the face of adversity: design and outcomes of rapid glaucoma assessment clinics during a pandemic recovery

Background: The provision of timely care to the high volume of glaucoma patients stratified as “low risk” following pandemic-related appointment deferrals continues to prove challenging for glaucoma specialists. It is unknown whether stratification as “low risk” remains valid over time, raising the potential risk of harm during this period if left unmonitored. This study aimed to evaluate whether Rapid Glaucoma Assessment Clinics (RGACs) are an effective method of assessing “low-risk” patients in order to identify those who may need an escalation of care, therefore reducing the risk of the future incidents of preventable vision loss. / Methods: RGACs were developed which comprised a brief advance telephone history by a clinician and then ophthalmic technician-measured visual acuity and intraocular pressure in clinic. We report outcomes from the first month of operation describing attendance patterns, the proportion of patients from this “low risk” cohort requiring escalation and underlying reasons for treatment escalations. / Results: 639 patients were invited to attend RGACs. 75% attended their booked appointment. Pre-attendance telephone consultations were associated with lower non-attendance rates (13.9% vs 29.3%, p < 0.00001). 15% of patients were no longer deemed to remain at “low risk” with further expedited clinical review scheduled. 10.4% of patients required an escalation in treatment following review. / Conclusions: RGACs are an effective approach to deliver high throughput clinical assessments for large numbers of “low-risk” glaucoma patients with deferred appointments. They enable the rapid identification and treatment of patients who would otherwise face significantly delayed review reducing the risk of future preventable vision loss

Introducing a Framework to Capture and Reuse Tacit Knowledge in Software Project Management

In rapidly growing global companies, comprehensive training programs as well as in depth sharing of knowledge are essential factors to maintain the quality of human capital despite rapid expansion. Different dimensions of Knowledge management address the need and approach to leverage dispersed knowledge in order to make it visible and accessible for everyone to improve organizational performance. However, there has been a scarcity of successful and holistic models that define and categorize tacit knowledge in order to capture and distribute it for the benefit of others. This paper focuses on developing a framework in order to capture experiences regarding software project management and to provide a platform for managers to inherit knowledge from and bequeath their learning to others at large organizations. In order to build up and enhance the framework, the majority of information was gleaned from intensive interviews with top software project managers at Infosys, a well-known global company in the field of software development and consulting services. The final framework we developed can act as a comprehensive data-repository for capturing, storing, searching, and distributing tacit knowledge of project managers

Adaptive Fuzzy PI Current Control of Grid Interact PV Inverter

Now a day‟s, Photo Voltaic (PV) power generation rapidly increasing. This power generation highly depending on the temperature and irradiation. When this power interface with grid through the voltage source inverter with PI controller. Its gains should be updated due to the parametric changes for the better performance. In This Work Fuzzy Controller updates the gains of the proportional integral (PI)s Controller under variable parametric conditions. the gaines of the PI Controller are updated based on the error current and change in error current through the fuzzy controller. The error current in direct and quadrature frame are the Inputs to the PI controller. The PI Controller generates the reference voltage to the pulse width modulation technique. Here reference voltage is compared with the carrier signal to generate the pulses to the 3-Ph Inverter connected to the grid. This controller has given well dynamic response with less steady state error and also given The less THD of the grid current compared to the PI and Fuzzy controller.It Is implemented and verified in MATLAB Simulink

Clinical risk stratification in glaucoma

Glaucoma is the leading cause of preventable sight loss in the United Kingdom and the provision of timely glaucoma care has been highlighted as a significant challenge in recent years. Following a recent high-profile investigation, The Healthcare Safety Investigation Branch recommended the validation of risk stratification models to safeguard the vision-related quality of life of glaucoma patients. There continues to be no nationally agreed evidence-based risk stratification model for glaucoma care across the United Kingdom. Some models have used simple measures of disease staging such as visual field mean deviation as surrogates for risk, but more refined, individualised risk stratification models should include factors related to both visual impairment and visual disability. Candidate tools should also incorporate both ocular and systemic co-morbidities, rate of disease progression, visual needs and driving status and undergo clinical refinement and validation to justify implementation. The disruption to routine glaucoma care caused by the COVID-19 pandemic has only highlighted the importance of such risk stratification models and has accelerated their development, application and evaluation. This review aims to critically appraise the available evidence underpinning current approaches for glaucoma risk stratification and to discuss how these may be applied to contemporary glaucoma care within the United Kingdom. Further research will be essential to justify and validate the utility of glaucoma risk stratification models in everyday clinical practice