Receiver Gain Modulation Circuit

A receiver gain modulation circuit (RGMC) was developed that modulates the power gain of the output of a radiometer receiver with a test signal. As the radiometer receiver switches between calibration noise references, the test signal is mixed with the calibrated noise and thus produces an ensemble set of measurements from which ensemble statistical analysis can be used to extract statistical information about the test signal. The RGMC is an enabling technology of the ensemble detector. As a key component for achieving ensemble detection and analysis, the RGMC has broad aeronautical and space applications. The RGMC can be used to test and develop new calibration algorithms, for example, to detect gain anomalies, and/or correct for slow drifts that affect climate-quality measurements over an accelerated time scale. A generalized approach to analyzing radiometer system designs yields a mathematical treatment of noise reference measurements in calibration algorithms. By treating the measurements from the different noise references as ensemble samples of the receiver state, i.e. receiver gain, a quantitative description of the non-stationary properties of the underlying receiver fluctuations can be derived. Excellent agreement has been obtained between model calculations and radiometric measurements. The mathematical formulation is equivalent to modulating the gain of a stable receiver with an externally generated signal and is the basis for ensemble detection and analysis (EDA). The concept of generating ensemble data sets using an ensemble detector is similar to the ensemble data sets generated as part of ensemble empirical mode decomposition (EEMD) with exception of a key distinguishing factor. EEMD adds noise to the signal under study whereas EDA mixes the signal with calibrated noise. It is mixing with calibrated noise that permits the measurement of temporal-functional variability of uncertainty in the underlying process. The RGMC permits the evaluation of EDA by modulating the receiver gain using an external signal. Without the RGMC, samples of calibrated references from radiometers form an ensemble data set of the natural occurring fluctuations within a receiver. By driving the gain of an otherwise stable receiver with an external signal, the conceptual framework and generalization of the mathematics of EDA can be tested. A series of measurements was conducted to evaluate and characterize the performance of the RGMC. Test signals stepped the RGMC across its dynamic range of performance using a radiometer that sampled four noise references; analysis indicates that the RGMC successfully modulated the receiver gain with an external signal. Calibration algorithms applied to four noise references demonstrate the RGMC produced ensemble data sets of the external signal

SiO masers in TX Cam: Simultaneous VLBA observations of two 43 GHz masers at four epochs

We present the results of simultaneous high resolution observations of v=1 and v=2, J=1-0 SiO masers toward TX Cam at four epochs covering a stellar cycle. Near maser maximum (Epochs III and IV), the individual components of both masers are distributed in ring-like structures but the ring is severely disrupted near stellar maser minimum (Epochs I and II). In Epochs III and IV there is a large overlap between the radii at which the two maser transitions occur. However in both epochs the average radius of the v=2 maser ring is smaller than for the v=1 maser ring, the difference being larger for Epoch IV. The observed relative ring radii in the two transitions, and the trends on the ring thickness, are close to those predicted by the model of Humphreys et al. (\cite{humphreys02}). In many individual features there is an almost exact overlap in space and velocity of emission from the two transitions, arguing against pure radiative pumping. At both Epochs III and IV in many spectral features only 50% of the flux density is recovered in our images, implying significant smooth maser structure. For both transitions we find that red- and blue-shifted masers occur in all parts of the rings, with relatively few masers at the systemic velocity. Thus there is no evidence for rotation, although the blue-shifted masers are somewhat more prominent to the west. At all four epochs red-shifted components are generally brighter than blue-shifted ones. At Epochs III and IV, we see many filamentary or spoke-like features in both v=1 and v=2 masers, especially in the red-shifted gas. These spokes show systematic velocity gradients consistent with a decelerating outward flow with increasing radius. We outline a possible model to explain why, given the presence of these spokes, there is a deficit of maser features at the systemic velocity.Comment: 15 pages, 10 figs, accepted to A&A, Abstract is reduced (see the paper for full length

Written emotional disclosure for women with ovarian cancer and their partners: randomised controlled trial.

OBJECTIVE: Written emotional disclosure for 15-20 min a day over 3 to 4 days improves physical and psychological health and may benefit cancer patients. However, no studies have tested the effectiveness of guided writing in cancer patients and their partners. A randomised controlled trial tested whether writing about the patient's diagnosis and treatment of ovarian cancer using the Guided Disclosure Protocol (GDP) is effective in reducing perceived stress and improving quality of life (QoL) in ovarian cancer couples. The study also tested two theories that may account for beneficial effects of written emotional disclosure, the cognitive processing hypothesis and the social interaction hypothesis. METHODS: Patients and their partners (N = 102 couples) were randomised to write at home for 15 min a day over 3 days about the patient's diagnosis and treatment using the GDP or what the patient did the previous day (control). Couples were assessed at baseline, 3- and 6-month follow-ups on the primary outcomes of perceived stress and QoL and secondary outcomes of intrusive thoughts (testing the cognitive processing hypothesis) and illness-related couple communication (testing the social interaction hypothesis). RESULTS: There were no main effects for any outcomes. However, in patients, the GDP improved QoL if illness-related couple communication improved and buffered the effect of intrusive thoughts on perceived stress. CONCLUSIONS: The GDP might benefit patients in certain circumstances, through changes in communication (in line with the social interaction hypothesis). Further research is needed to determine whether patients benefit from interventions to improve illness-related couple communication and under which conditions. Copyright © 2013 John Wiley & Sons, Ltd

Vitamin D and Its Role During Pregnancy in Attaining Optimal Health of Mother and Fetus

Despite its discovery a hundred years ago, vitamin D has emerged as one of the most controversial nutrients and prohormones of the 21st century. Its role in calcium metabolism and bone health is undisputed but its role in immune function and long-term health is debated. There are clear indicators from in vitro and animal in vivo studies that point to vitamin D’s indisputable role in both innate and adaptive immunity; however, the translation of these findings to clinical practice, including the care of the pregnant woman, has not occurred. Until recently, there has been a paucity of data from randomized controlled trials to establish clear cut beneficial effects of vitamin D supplementation during pregnancy. An overview of vitamin metabolism, states of deficiency, and the results of recent clinical trials conducted in the U.S. are presented with an emphasis on what is known and what questions remain to be answered

Personality or role? Comparisons of Turkish leaders across different institutional positions

Personality approaches to politics are often criticized for not examining the effect that institutional role constraints have on individual beliefs and preferences. When leaders appear to change their stance when they change roles, it is assumed that roles have a determining influence. Modern personality theory and contemporary sociological role theory, however, view the effects of roles as interacting with agents’ personalities. In this article, we investigate this question by comparing personality profiles of three Turkish leaders (Özal, Demirel, and Gül) during their tenure as prime minister and during their subsequent time as president. For Gül, we perform an additional comparison during his time as foreign minister. The personality profiles are in the form of quantitative scores generated from machine-coded content analysis of leaders’ words using the Leadership Trait Analysis method. We hypothesize that different leaders will be more susceptible to changing role contexts, depending on core personality traits, and that different traits are more likely to change with new roles. Overall, our results suggest that leaders’ traits are fairly resistant to changes across roles and that task orientation is the most likely trait to change as leaders adapt to different role demands and expectations. This study makes a contribution to our understanding of the interaction between personality and political contexts by offering specific theoretically derived hypotheses and by empirically and statistically examining a preliminary set of expectations that could be applied more broadly to other leaders. © 2016 International Society of Political Psycholog

The impact of a computerised test of attention and activity (QbTest) on diagnostic decision-making in children and young people with suspected ADHD: single-blind randomised controlled trial

Background: Diagnosis of attention deficit hyperactivity disorder (ADHD) relies on subjective methods which can lead to diagnostic uncertainty and delay. This trial evaluated the impact of providing a computerised test of attention and activity (QbTest) report on the speed and accuracy of diagnostic decision making in children with suspected ADHD. Methods: Randomised, parallel, single-blind controlled trial in mental health and community paediatric clinics in England. Participants were 6-17 years-old and referred for ADHD diagnostic assessment; all underwent assessment-as-usual, plus QbTest. Participants and their clinician were randomised to either receive the QbTest report immediately (QbOpen group) or the report was withheld (QbBlind group). The primary outcome was number of consultations until a diagnostic decision confirming/excluding ADHD within six-months from baseline. Health economic cost-effectiveness and cost utility analysis was conducted. Assessing QbTest Utility in ADHD: A Randomised Controlled Trial was registered at ClinicalTrials.gov (https://clinicaltrials.gov/ct2/show/NCT02209116). Results: One hundred and thirty two participants were randomised to QbOpen group (123 analysed) and 135 to QbBlind group (127 analysed). Clinicians with access to the QbTest report (QbOpen) were more likely to reach a diagnostic decision about ADHD (Hazard Ratio 1.44, 95% CI 1.04 to 2.01). At six-months, 76% of those with a QbTest report had received a diagnostic decision, compared with 50% without. QbTest reduced appointment length by 15% (Time Ratio 0.85, 95% CI 0.77 to 0.93), increased clinicians’ confidence in their diagnostic decisions (Odds Ratio 1.77, 95% CI 1.09 to 2.89) and doubled the likelihood of excluding ADHD. There was no difference in diagnostic accuracy. Health economic analysis showed a position of strict dominance, however cost savings were small suggesting that the impact of providing the QbTest report within this trial can best be viewed as ‘cost neutral’. Conclusion: QbTest may increase the efficiency of ADHD assessment pathway allowing greater patient throughput with clinicians reaching diagnostic decisions faster without compromising diagnostic accuracy

Antimicrobial use Guidelines for Treatment of Respiratory Tract Disease in Dogs and Cats: Antimicrobial Guidelines Working Group of the International Society for Companion Animal Infectious Diseases

Respiratory tract disease can be associated with primary or secondary bacterial infections in dogs and cats and is a common reason for use and potential misuse, improper use, and overuse of antimicrobials. There is a lack of comprehensive treatment guidelines such as those that are available for human medicine. Accordingly, the International Society for Companion Animal Infectious Diseases convened a Working Group of clinical microbiologists, pharmacologists, and internists to share experiences, examine scientific data, review clinical trials, and develop these guidelines to assist veterinarians in making antimicrobial treatment choices for use in the management of bacterial respiratory diseases in dogs and cats.M.R. Lappin, J. Blondeau, D. Boothe, E.B. Breitschwerdt, L. Guardabassi, D.H. Lloyd, M.G. Papich, S.C. Rankin, J.E. Sykes, J. Turnidge, and J.S. Wees

IMPLEmenting a clinical practice guideline for acute low back pain evidence-based manageMENT in general practice (IMPLEMENT) : cluster randomised controlled trial study protocol

Background: Evidence generated from reliable research is not frequently implemented into clinical practice. Evidence-based clinical practice guidelines are a potential vehicle to achieve this. A recent systematic review of implementation strategies of guideline dissemination concluded that there was a lack of evidence regarding effective strategies to promote the uptake of guidelines. Recommendations from this review, and other studies, have suggested the use of interventions that are theoretically based because these may be more effective than those that are not. An evidencebased clinical practice guideline for the management of acute low back pain was recently developed in Australia. This provides an opportunity to develop and test a theory-based implementation intervention for a condition which is common, has a high burden, and for which there is an evidence-practice gap in the primary care setting. Aim: This study aims to test the effectiveness of a theory-based intervention for implementing a clinical practice guideline for acute low back pain in general practice in Victoria, Australia. Specifically, our primary objectives are to establish if the intervention is effective in reducing the percentage of patients who are referred for a plain x-ray, and improving mean level of disability for patients three months post-consultation. Methods/Design: This study protocol describes the details of a cluster randomised controlled trial. Ninety-two general practices (clusters), which include at least one consenting general practitioner, will be randomised to an intervention or control arm using restricted randomisation. Patients aged 18 years or older who visit a participating practitioner for acute non-specific low back pain of less than three months duration will be eligible for inclusion. An average of twenty-five patients per general practice will be recruited, providing a total of 2,300 patient participants. General practitioners in the control arm will receive access to the guideline using the existing dissemination strategy. Practitioners in the intervention arm will be invited to participate in facilitated face-to-face workshops that have been underpinned by behavioural theory. Investigators (not involved in the delivery of the intervention), patients, outcome assessors and the study statistician will be blinded to group allocation. Trial registration: Australian New Zealand Clinical Trials Registry ACTRN012606000098538 (date registered 14/03/2006).The trial is funded by the NHMRC by way of a Primary Health Care Project Grant (334060). JF has 50% of her time funded by the Chief Scientist Office3/2006). of the Scottish Government Health Directorate and 50% by the University of Aberdeen. PK is supported by a NHMRC Health Professional Fellowship (384366) and RB by a NHMRC Practitioner Fellowship (334010). JG holds a Canada Research Chair in Health Knowledge Transfer and Uptake. All other authors are funded by their own institutions