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Head to head prospective comparison of quantitative lung scintigraphy and segment counting in predicting pulmonary function of lung cancer patients undergoing video-assisted thoracoscopic lobectomy

Prediction of post-operative pulmonary function in lung cancer patients before tumor resection is essential for patient selection for surgery and is conventionally done with a non-imaging segment counting method (SC) or a two-dimensional planar lung perfusion scintigraphy (PS). The purpose of this study was to compare quantitative analysis of PS to single photon emission computed tomography/computed tomography (SPECT/CT) and to estimate the accuracy of SC, PS and SPECT/CT in predicting post-operative pulmonary function in patients undergoing lobectomy. Methods: Seventy-five non-small cell lung cancer (NSCLC) patients planned for lobectomy were prospectively enrolled (68% males, average age 68.1±8 years ). All patients completed pre-operative forced expiratory volume capacity (FEV1), diffusing capacity of the lung for carbon monoxide (DLCO), Tc99m-MAA lung perfusion scintigraphy with PS and SPECT/CT quantification. A subgroup of 60 patients underwent video-assisted thoracoscopic (VATS) lobectomy and measurement of post-operative FEV1 and DLCO. Relative uptake of the lung lobes estimated by PS and SPECT/CT were compared. Predicted post-operative FEV1 and DLCO were derived from SC, PS and SPECT/CT. Prediction results were compared between the different methods and the true post-operative measurements in patients who underwent lobectomy. Results: Relative uptake measurements differed significantly between PS and SPECT/CT in right lung lobes, with a mean difference of -8.2±3.8, 18.0±5.0 and -11.5±6.1 for right upper, middle and lower lobes respectively (p<0.001). The differences between the methods in the left lung lobes were minor with a mean difference of -0.4±4.4 (p>0.05) and -2.0±4.0 (p<0.001) for left upper and lower lobes respectively. No significant difference and strong correlation (R=0.6-0.76, p<0.001) were found between predicted post-operative lung function values according to SC, PS, SPECT/CT and the actual post-operative FEV1 and DLCO. Conclusion: Although lobar quantification parameters differed significantly between PS and SPECT/CT, no significant differences were found between the predicted post-operative lung function results derived from these methods and the actual post-operative results. The additional time and effort of SPECT/CT quantification may not have an added value in patient selection for surgery. SPECT/CT may be advantageous in patients planned for right lobectomies but further research is warranted.




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Data-driven motion detection and event-by-event correction for brain PET: Comparison with Vicra

Head motion degrades image quality and causes erroneous parameter estimates in tracer kinetic modeling in brain PET studies. Existing motion correction methods include frame-based image-registration (FIR) and correction using real-time hardware-based motion tracking (HMT) information. However, FIR cannot correct for motion within one predefined scan period while HMT is not readily available in the clinic since it typically requires attaching a tracking device to the patient. In this study, we propose a motion correction framework with a data-driven algorithm, i.e., using the PET raw data itself, to address these limitations. Methods: We propose a data-driven algorithm, Centroid of Distribution (COD), to detect head motion. In COD, the central coordinates of the line of response (LOR) of all events are averaged over 1-sec intervals to generate a COD trace. A point-to-point change in the COD trace in one direction that exceeded a user-defined threshold was defined as a time point of head motion, which was followed by manually adding additional motion time points. All the frames defined by such time points were reconstructed without attenuation correction and rigidly registered to a reference frame. The resulting transformation matrices were then used to perform the final motion compensated reconstruction. We applied the new COD framework to 23 human dynamic datasets, all containing large head motions, with 18F-FDG (N = 13) and 11C-UCB-J (N = 10), and compared its performance with FIR and with HMT using the Vicra, which can be considered as the "gold standard". Results: The COD method yielded 1.0±3.2% (mean ± standard deviation across all subjects and 12 grey matter regions) SUV difference for 18F-FDG (3.7±5.4% for 11C-UCB-J) compared to HMT while no motion correction (NMC) and FIR yielded -15.7±12.2% (-20.5±15.8%) and -4.7±6.9% (-6.2±11.0%), respectively. For 18F-FDG dynamic studies, COD yielded differences of 3.6±10.9% in Ki value as compared to HMT, while NMC and FIR yielded -18.0±39.2% and -2.6±19.8%, respectively. For 11C-UCB-J, COD yielded 3.7±5.2% differences in VT compared to HMT, while NMC and FIR yielded -20.0±12.5% and -5.3±9.4%, respectively. Conclusion: The proposed COD-based data-driven motion correction method outperformed FIR and achieved comparable or even better performance as compared to the Vicra HMT method in both static and dynamic studies.




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Interim PET evaluation in diffuse large B-cell lymphoma employing published recommendations: Comparison of the Deauville 5-point scale and the {Delta}SUVmax method

The value of interim 18F-fluorodeoxyglucose positron emission tomography (iPET) guided treatment decisions in patients with diffuse large B-cell lymphoma (DLBCL) has been the subject of much debate. This investigation focuses on a comparison of the Deauville score and the deltaSUVmax (SUVmax) approach – two methods to assess early metabolic response to standard chemotherapy in DLBCL. Methods: Of 609 DLBCL patients participating in the Positron Emission Tomography-guided Therapy of Aggressive non-Hodgkin Lymphomas (PETAL) trial, iPET scans of 596 patients originally evaluated using the SUVmax method were available for post-hoc assessment of the Deauville score. A commonly used definition of an unfavorable iPET result according to the Deauville score is an uptake greater than that of the liver, whereas an unfavorable iPET scan with regard to the SUVmax approach is characterized as a relative reduction of the maximum standardized uptake value between baseline and iPET staging of less than or equal to 66%. We investigated the two methods’ correlation and concordance by Spearman’s rank correlation coefficient and the agreement in classification, respectively. We further used Kaplan-Meier curves and Cox regression to assess differences in survival between patient subgroups defined by the pre-specified cut-offs. Time-dependent receiver operating curve analysis provided information on the methods’ respective discrimination performance. Results: Deauville score and SUVmax approach differed in their iPET-based prognosis. The SUVmax approach outperformed the Deauville score in terms of discrimination performance – most likely due to a high number of false-positive decisions by the Deauville score. Cut-off-independent discrimination performance remained low for both methods, but cut-off-related analyses showed promising results. Both favored the SUVmax approach, e.g. for the segregation by iPET response, where the event-free survival hazard ratio was 3.14 (95% confidence interval (CI): 2.22 – 4.46) for SUVmax and 1.70 (95% CI: 1.29 – 2.24) for the Deauville score. Conclusion: When considering treatment intensification, the currently used Deauville score cut-off of an uptake above that of the liver seems to be inappropriate and associated with potential harm for DLBCL patients. The SUVmax criterion of a relative reduction of the maximum standardized uptake value of less than or equal to 66% should be considered as an alternative.




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A Good Deal? Assessing the Paris Climate Agreement

Invitation Only Research Event

16 December 2015 - 5:00pm to 6:30pm

Chatham House, London

Event participants

Shane Tomlinson, Senior Research Fellow, Energy, Environment and Resources Department, Chatham House

Following the conclusion of the Paris climate negotiations, this expert roundtable will examine the critical elements of the final agreement and what this means for the future of energy and climate policy in key countries.

The discussion will examine what the agreement means for keeping global average temperatures below two degrees Celsius and assess whether ambition will be ratcheted over time. It will also look at the primary implications of the outcome for key regions and countries such as the EU, United States, China and India. Finally, the session will also consider the next steps in terms of implementing the agreement. 

Attendance at this event is by invitation only. 

Owen Grafham

Manager, Energy, Environment and Resources Programme
+44 (0)20 7957 5708




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Post-Paris: Taking Forward the Global Climate Change Deal

21 April 2016

Inevitably, the compromises of the Paris Agreement make it both a huge achievement and an imperfect solution to the problem of global climate change.

Rob Bailey

Former Research Director, Energy, Environment and Resources
Shane Tomlinson
Former Senior Research Fellow, Energy, Environment and Resources

2016-04-21-post-paris.jpg

The slogan '1.5 Degrees' is projected on the Eiffel Tower as part of the World Climate Change Conference 2015 (COP21) on 11 December 2015 in Paris, France. Photo by Getty Images.

Summary

  • The Paris Agreement, reached at COP21, was a triumph of diplomacy. The deal can be characterized as: flexible, combining a ‘hard’ legal shell and a ‘soft’ enforcement mechanism; inclusive, as it was adopted by all 196 parties to the UNFCCC and is therefore the first truly global climate deal; messy, as the bottom-up process of creating nationally determined contributions means the system is unstandardized; non-additive, as the contributions do not currently deliver the agreement’s stated long-term goal of keeping the rise in global average temperature to ‘well below 2˚C’; and dynamic, as the deal establishes a ratchet mechanism that requires more ambitious contributions every five years.
  • The next five years are critical for keeping the below 2˚C goal within reach. A ‘facilitative dialogue’ starting in 2018 will give states the opportunity to revisit their contributions in advance of the agreement entering into force in 2020. International forums, such as the G7 and G20, can play a crucial role in kickstarting these efforts.
  • The ‘coalitions of the willing’ and clubs that were launched under the Lima-Paris Action Agenda provide an innovative space for state and non-state actors to unlock transformational change. However, it is important that these groups set specific and measurable targets to ensure effective delivery of objectives.
  • The post-Paris regime implies a significant role for civil society organizations. However, in many countries the ‘safe operating space’ both for these organizations and for the media is shrinking. Expanding the capacity of civil society and the media in areas such as communications, litigation, project implementation and technical expertise will be important if they are to support the regime effectively.




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Estimation of Insulin Secretion Rates from C-Peptide Levels: Comparison of Individual and Standard Kinetic Parameters for C-Peptide Clearance

Eve Van Cauter
Mar 1, 1992; 41:368-377
Original Article




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Comparison of 3 Interpretation Criteria for 68Ga-PSMA11 PET Based on Inter- and Intrareader Agreement

PET using radiolabeled prostate-specific membrane antigen (PSMA) is now being more widely adopted as a valuable tool to evaluate patients with prostate cancer (PC). Recently, 3 different criteria for interpretation of PSMA PET were published: the European Association of Nuclear Medicine (EANM) criteria, the Prostate Cancer Molecular Imaging Standardized Evaluation criteria, and the PSMA Reporting and Data System. We compared these 3 criteria in terms of interreader, intrareader, and intercriteria agreement. Methods: Data from 104 patients prospectively enrolled in research protocols at our institution were retrospectively reviewed. The cohort consisted of 2 groups: 47 patients (mean age, 64.2 y old) who underwent Glu-NH-CO-NH-Lys-(Ahx)-[68Ga(HBED-CC)] (68Ga-PSMA11) PET/MRI for initial staging of biopsy-proven intermediate- or high-risk PC, and 57 patients (mean age, 70.5 y old) who underwent 68Ga-PSMA11 PET/CT because of biochemically recurrent PC. Three nuclear medicine physicians independently evaluated all 68Ga-PSMA11 PET/MRI and PET/CT studies according to the 3 interpretation criteria. Two of them reevaluated all studies 6 mo later in the same manner and masked to the initial reading. The Gwet agreement coefficient was calculated to evaluate interreader, intrareader, and intercriteria agreement based on the following sites: local lesion (primary tumor or prostate bed after radical prostatectomy), lymph node metastases, and other metastases. Results: In the PET/MRI group, interreader, intrareader, and intercriteria agreement ranged from substantial to almost perfect for any site according to all 3 criteria. In the PET/CT group, interreader agreement ranged from substantial to almost perfect except for judgment of distant metastases based on the PSMA Reporting and Data System (Gwet agreement coefficient, 0.57; moderate agreement), in which the most frequent cause of disagreement was lung nodules. Intrareader agreement ranged from substantial to almost perfect for any site according to all 3 criteria. Intercriteria agreement for each site was also substantial to almost perfect. Conclusion: Although the 3 published criteria have good interreader and intrareader reproducibility in evaluating 68Ga-PSMA11 PET, there are some factors causing interreader disagreement. Further work is needed to address this issue.




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Head-to-Head Comparison of 68Ga-PSMA-11 with 18F-PSMA-1007 PET/CT in Staging Prostate Cancer Using Histopathology and Immunohistochemical Analysis as a Reference Standard

18F-PSMA-1007 is a novel prostate-specific membrane antigen (PSMA)–based radiopharmaceutical for imaging prostate cancer (PCa). The aim of this study was to compare the diagnostic accuracy of 18F-PSMA-1007 with 68Ga-PSMA-11 PET/CT in the same patients presenting with newly diagnosed intermediate- or high-risk PCa. Methods: Sixteen patients with intermediate- or high-risk PCa underwent 18F-PSMA-1007 and 68Ga-PSMA-11 PET/CT within 15 d. PET findings were compared between the 2 radiotracers and with reference-standard pathologic specimens obtained from radical prostatectomy. The Cohen -coefficient was used to assess the concordance between 18F-PSMA-1007 and 68Ga-PSMA-11 for detection of intraprostatic lesions. The McNemar test was used to assess agreement between intraprostatic PET/CT findings and histopathologic findings. Sensitivity, specificity, positive predictive value, and negative predictive value were reported for each radiotracer. SUVmax was measured for all lesions, and tumor-to-background activity was calculated. Areas under receiver-operating-characteristic curves were calculated for discriminating diseased from nondiseased prostate segments, and optimal SUV cutoffs were calculated using the Youden index for each radiotracer. Results: PSMA-avid lesions in the prostate were identified in all 16 patients with an almost perfect concordance between the 2 tracers ( ranged from 0.871 to 1). Aside from the dominant intraprostatic lesion, similarly detected by both radiotracers, a second less intense positive focus was detected in 4 patients only with 18F-PSMA-1007. Three of these secondary foci were confirmed as Gleason grade 3 lesions, whereas the fourth was shown on pathologic examination to represent chronic prostatitis. Conclusion: This pilot study showed that both 18F-PSMA-1007 and 68Ga-PSMA-11 identify all dominant prostatic lesions in patients with intermediate- or high-risk PCa at staging. 18F-PSMA-1007, however, may detect additional low-grade lesions of limited clinical relevance.




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Comparison of dietary macronutrient patterns of 14 popular named dietary programmes for weight and cardiovascular risk factor reduction in adults: systematic review and network meta-analysis of randomised trials




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Breaking the Habit: Why Major Oil Companies Are Not ‘Paris-Aligned’

Invitation Only Research Event

23 October 2019 - 8:30am to 10:00am

Chatham House | 10 St James's Square | London | SW1Y 4LE

Event participants

Andrew Grant, Carbon Tracker Initiative
Chair: Siân Bradley, Research Fellow, Energy, Environment and Resources, Chatham House

The investment community is increasingly seeking to assess the alignment of their portfolios with the Paris Agreement. In a recent update to their Two Degrees of Separation report, Carbon Tracker assessed the capital expenditure of listed oil and gas producers against ‘well below’ 2C targets, and for the first time, against short-term actions at the project level.

The speaker will present the key findings of the report and will argue that every oil major is betting heavily against a low-carbon world by investing in projects that are contrary to the Paris goals.

This roundtable discussion will further explore the report findings and consider what investors, regulators and oil and gas companies can do to encourage alignment  with the Paris Agreement ahead of 2020.  

Attendance at this event is by invitation only.

Event attributes

Chatham House Rule




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Low molecular weight heparin does not prevent VTE after knee arthroscopy, studies show




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It’s Relative: A Crosscountry Comparison of Family-Migration Policies and Flows

As policymakers in a number of countries, the United States among them, debate limiting family-based immigration, this issue brief explores family-migration trends and policies in the United States, Australia, Canada, the United Kingdom, and several other European countries. Family admissions play a key role, even in countries that prioritize economic or other immigration streams.




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Immigrants and WIOA Services: Comparison of Sociodemographic Characteristics of Native- and Foreign-Born Adults in the United States

As federal and state governments ramp up efforts to implement the Workforce Innovation and Opportunity Act, these fact sheets compare key characteristics of the foreign born and the U.S. born that are relevant to understanding needs for adult education and workforce training services. The fact sheets cover the United States, the 20 states and 25 counties with the largest immigrant populations, and New York City.




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PIONEER 1: Randomized Clinical Trial of the Efficacy and Safety of Oral Semaglutide Monotherapy in Comparison With Placebo in Patients With Type 2 Diabetes

Vanita R. Aroda
Sep 1, 2019; 42:1724-1732
Emerging Therapies: Drugs and Regimens




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A Randomized Controlled Trial Comparing Glargine U300 and Glargine U100 for the Inpatient Management of Medicine and Surgery Patients With Type 2 Diabetes: Glargine U300 Hospital Trial

OBJECTIVE

The role of U300 glargine insulin for the inpatient management of type 2 diabetes (T2D) has not been determined. We compared the safety and efficacy of glargine U300 versus glargine U100 in noncritically ill patients with T2D.

RESEARCH DESIGN AND METHODS

This prospective, open-label, randomized clinical trial included 176 patients with poorly controlled T2D (admission blood glucose [BG] 228 ± 82 mg/dL and HbA1c 9.5 ± 2.2%), treated with oral agents or insulin before admission. Patients were treated with a basal-bolus regimen with glargine U300 (n = 92) or glargine U100 (n = 84) and glulisine before meals. We adjusted insulin daily to a target BG of 70–180 mg/dL. The primary end point was noninferiority in the mean difference in daily BG between groups. The major safety outcome was the occurrence of hypoglycemia.

RESULTS

There were no differences between glargine U300 and U100 in mean daily BG (186 ± 40 vs. 184 ± 46 mg/dL, P = 0.62), percentage of readings within target BG of 70–180 mg/dL (50 ± 27% vs. 55 ± 29%, P = 0.3), length of stay (median [IQR] 6.0 [4.0, 8.0] vs. 4.0 [3.0, 7.0] days, P = 0.06), hospital complications (6.5% vs. 11%, P = 0.42), or insulin total daily dose (0.43 ± 0.21 vs. 0.42 ± 0.20 units/kg/day, P = 0.74). There were no differences in the proportion of patients with BG <70 mg/dL (8.7% vs. 9.5%, P > 0.99), but glargine U300 resulted in significantly lower rates of clinically significant hypoglycemia (<54 mg/dL) compared with glargine U100 (0% vs. 6.0%, P = 0.023).

CONCLUSIONS

Hospital treatment with glargine U300 resulted in similar glycemic control compared with glargine U100 and may be associated with a lower incidence of clinically significant hypoglycemia.




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Preparing Newcomers for the Jobs of Today and the Labor Markets of Tomorrow

This Migration Policy Institute Europe webinar examines possible scenarios for how social, economic, and technological trends could affect jobs, labor market policy, education and social policies, and migrant integration. Speakers also explored the potential of coding schools for refugees to help alleviate skills shortages and provide a pathway to work.




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Side-by-Side Comparison of 2013 Senate Immigration Bill with 2006 and 2007 Senate Legislation

This fact sheet compares key components of immigration reform outlined in the 2013 Senate immigration bill against provisions included in bills considered by the Senate in 2006 and 2007: border security, detention, and enforcement; worksite enforcement; visa reforms; earned legalization of unauthorized immigrants; strengthening the U.S. economy and workforce; and integration of new Americans.




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Side-by-Side Comparison of the 2013 Senate Immigration Framework with 2006 and 2007 Senate Legislation

MPI has completed an analysis of the major provisions in the 2013 framework, comparing them to provisions of the legislation the Senate considered in 2006 and 2007. 

This fact sheet is formatted as a chart comparing the framework of comprehensive immigration reform outlined in the 2013 Senate immigration bill against provisions included in bills considered by the Senate in 2006 and 2007.




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Side-by-Side Comparison of 2013 Senate Immigration Bill with Individual 2013 House Bills

This fact sheet offers a detailed review of the comprehensive immigration reform legislation approved by the U.S. Senate in June 2013 and compares its major provisions with those of the five targeted immigration bills approved by the House Judiciary Committee and the House Homeland Security Committee.




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Taylor Swift's Paris concert to air on ABC May 17

Taylor Swift announced her City of Lover concert, which took place in Paris, will air on ABC on May 17 at 10 p.m.




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Preparing for the Unknown: Designing Effective Predeparture Orientation for Resettling Refugees

Refugees encounter a range of challenges after resettlement—from adjusting to a new culture and language, to finding a job. Many resettlement countries invest in predeparture orientation to help refugees develop the knowledge, skills, and attitudes to face these challenges. This report explores the many forms these programs take, highlighting important design questions and key elements that effective programs share.





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Taking instructions and preparing for mediation / [Rodney Burr?].




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Probate rules : preparing grants of probate & letters of administration / paper presented by Rosemary Caruso, Tindall Gask Bentley.




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Probate rules : preparing grants of probate & letters of administration / paper presented by Rosemary Caruso, Tindall Gask Bentley.




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Meeting Paris: A Book of Poems.




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Directions for preparing aerated medicinal waters, by means of the improved glass machines made at Leith Glass-Works.

Edinburgh : printed for William Creech, 1787.




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Dispensatorium homoeopathicum / auctore Dr. Caspario.

Lipsiae : Sumtibus Baumgaertneri, 1829.




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Documents inédits sur la grande peste de 1348 (Consultation de la Faculte de Paris, consultation d'un praticien de Montpellier, description de Guillaume de Machaut) / publiés avec une introduction et des notes par L.-A. Joseph Michon.

Londres : Paris, 1860.




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Du scorbut épidémie observée pendant le siége de Paris / par Michel V. Georgesco.

Paris : A. Delahaye, 1872.




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Eloge upon Baron G. Dupuytren ... / by E. Pariset ; translated, with notes, by J.I. Ikin.

London : J. Churchill, 1837.




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Essai sur les moyens de perfectionner et d'étendre l'art de l'anatomiste, présenté et soutenu à l'Ecole de médecine de Paris le lundi 11 fructidor an XI / par Constant Dumeril.

Paris : Baudouin, 1803.




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The marriage of King Charles I and Princess Henrietta Maria in Notre Dame cathedral, Paris, 1625. Engraving by N. Dupuis, 1728, after L. Chéron.

London : Printed & sold by Thos. & John Bowles, printsellers, [1728]




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How one NHL team is preparing to reopen its arena

The San Jose Sharks are considering different scenarios in how to handle the return of hockey. The questions the Sharks are asking themselves are likely the same ones the Caps are as everyone waits for the end of the coronavirus pandemic.




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Application of weighted and unordered majorization orders in comparisons of parallel systems with exponentiated generalized gamma components

Abedin Haidari, Amir T. Payandeh Najafabadi, Narayanaswamy Balakrishnan.

Source: Brazilian Journal of Probability and Statistics, Volume 34, Number 1, 150--166.

Abstract:
Consider two parallel systems, say $A$ and $B$, with respective lifetimes $T_{1}$ and $T_{2}$ wherein independent component lifetimes of each system follow exponentiated generalized gamma distribution with possibly different exponential shape and scale parameters. We show here that $T_{2}$ is smaller than $T_{1}$ with respect to the usual stochastic order (reversed hazard rate order) if the vector of logarithm (the main vector) of scale parameters of System $B$ is weakly weighted majorized by that of System $A$, and if the vector of exponential shape parameters of System $A$ is unordered mojorized by that of System $B$. By means of some examples, we show that the above results can not be extended to the hazard rate and likelihood ratio orders. However, when the scale parameters of each system divide into two homogeneous groups, we verify that the usual stochastic and reversed hazard rate orders can be extended, respectively, to the hazard rate and likelihood ratio orders. The established results complete and strengthen some of the known results in the literature.




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Time series of count data: A review, empirical comparisons and data analysis

Glaura C. Franco, Helio S. Migon, Marcos O. Prates.

Source: Brazilian Journal of Probability and Statistics, Volume 33, Number 4, 756--781.

Abstract:
Observation and parameter driven models are commonly used in the literature to analyse time series of counts. In this paper, we study the characteristics of a variety of models and point out the main differences and similarities among these procedures, concerning parameter estimation, model fitting and forecasting. Alternatively to the literature, all inference was performed under the Bayesian paradigm. The models are fitted with a latent AR($p$) process in the mean, which accounts for autocorrelation in the data. An extensive simulation study shows that the estimates for the covariate parameters are remarkably similar across the different models. However, estimates for autoregressive coefficients and forecasts of future values depend heavily on the underlying process which generates the data. A real data set of bankruptcy in the United States is also analysed.




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A comparison of spatial predictors when datasets could be very large

Jonathan R. Bradley, Noel Cressie, Tao Shi.

Source: Statistics Surveys, Volume 10, 100--131.

Abstract:
In this article, we review and compare a number of methods of spatial prediction, where each method is viewed as an algorithm that processes spatial data. To demonstrate the breadth of available choices, we consider both traditional and more-recently-introduced spatial predictors. Specifically, in our exposition we review: traditional stationary kriging, smoothing splines, negative-exponential distance-weighting, fixed rank kriging, modified predictive processes, a stochastic partial differential equation approach, and lattice kriging. This comparison is meant to provide a service to practitioners wishing to decide between spatial predictors. Hence, we provide technical material for the unfamiliar, which includes the definition and motivation for each (deterministic and stochastic) spatial predictor. We use a benchmark dataset of $mathrm{CO}_{2}$ data from NASA’s AIRS instrument to address computational efficiencies that include CPU time and memory usage. Furthermore, the predictive performance of each spatial predictor is assessed empirically using a hold-out subset of the AIRS data.




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Errata: A survey of Bayesian predictive methods for model assessment, selection and comparison

Aki Vehtari, Janne Ojanen.

Source: Statistics Surveys, Volume 8, , 1--1.

Abstract:
Errata for “A survey of Bayesian predictive methods for model assessment, selection and comparison” by A. Vehtari and J. Ojanen, Statistics Surveys , 6 (2012), 142–228. doi:10.1214/12-SS102.




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A survey of Bayesian predictive methods for model assessment, selection and comparison

Aki Vehtari, Janne Ojanen

Source: Statist. Surv., Volume 6, 142--228.

Abstract:
To date, several methods exist in the statistical literature for model assessment, which purport themselves specifically as Bayesian predictive methods. The decision theoretic assumptions on which these methods are based are not always clearly stated in the original articles, however. The aim of this survey is to provide a unified review of Bayesian predictive model assessment and selection methods, and of methods closely related to them. We review the various assumptions that are made in this context and discuss the connections between different approaches, with an emphasis on how each method approximates the expected utility of using a Bayesian model for the purpose of predicting future data.




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A comparison of group testing architectures for COVID-19 testing. (arXiv:2005.03051v1 [stat.ME])

An important component of every country's COVID-19 response is fast and efficient testing -- to identify and isolate cases, as well as for early detection of local hotspots. For many countries, producing a sufficient number of tests has been a serious limiting factor in their efforts to control COVID-19 infections. Group testing is a well-established mathematical tool, which can provide a serious and rapid improvement to this situation. In this note, we compare several well-established group testing schemes in the context of qPCR testing for COVID-19. We include example calculations, where we indicate which testing architectures yield the greatest efficiency gains in various settings. We find that for identification of individuals with COVID-19, array testing is usually the best choice, while for estimation of COVID-19 prevalence rates in the total population, Gibbs-Gower testing usually provides the most accurate estimates given a fixed and relatively small number of tests. This note is intended as a helpful handbook for labs implementing group testing methods.




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Handbook of geotechnical testing : basic theory, procedures and comparison of standards

Li, Yanrong (Writer on geology), author.
0429323743 electronic book




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Active ranking from pairwise comparisons and when parametric assumptions do not help

Reinhard Heckel, Nihar B. Shah, Kannan Ramchandran, Martin J. Wainwright.

Source: The Annals of Statistics, Volume 47, Number 6, 3099--3126.

Abstract:
We consider sequential or active ranking of a set of $n$ items based on noisy pairwise comparisons. Items are ranked according to the probability that a given item beats a randomly chosen item, and ranking refers to partitioning the items into sets of prespecified sizes according to their scores. This notion of ranking includes as special cases the identification of the top-$k$ items and the total ordering of the items. We first analyze a sequential ranking algorithm that counts the number of comparisons won, and uses these counts to decide whether to stop, or to compare another pair of items, chosen based on confidence intervals specified by the data collected up to that point. We prove that this algorithm succeeds in recovering the ranking using a number of comparisons that is optimal up to logarithmic factors. This guarantee does depend on whether or not the underlying pairwise probability matrix, satisfies a particular structural property, unlike a significant body of past work on pairwise ranking based on parametric models such as the Thurstone or Bradley–Terry–Luce models. It has been a long-standing open question as to whether or not imposing these parametric assumptions allows for improved ranking algorithms. For stochastic comparison models, in which the pairwise probabilities are bounded away from zero, our second contribution is to resolve this issue by proving a lower bound for parametric models. This shows, perhaps surprisingly, that these popular parametric modeling choices offer at most logarithmic gains for stochastic comparisons.




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A comparison of principal component methods between multiple phenotype regression and multiple SNP regression in genetic association studies

Zhonghua Liu, Ian Barnett, Xihong Lin.

Source: The Annals of Applied Statistics, Volume 14, Number 1, 433--451.

Abstract:
Principal component analysis (PCA) is a popular method for dimension reduction in unsupervised multivariate analysis. However, existing ad hoc uses of PCA in both multivariate regression (multiple outcomes) and multiple regression (multiple predictors) lack theoretical justification. The differences in the statistical properties of PCAs in these two regression settings are not well understood. In this paper we provide theoretical results on the power of PCA in genetic association testings in both multiple phenotype and SNP-set settings. The multiple phenotype setting refers to the case when one is interested in studying the association between a single SNP and multiple phenotypes as outcomes. The SNP-set setting refers to the case when one is interested in studying the association between multiple SNPs in a SNP set and a single phenotype as the outcome. We demonstrate analytically that the properties of the PC-based analysis in these two regression settings are substantially different. We show that the lower order PCs, that is, PCs with large eigenvalues, are generally preferred and lead to a higher power in the SNP-set setting, while the higher-order PCs, that is, PCs with small eigenvalues, are generally preferred in the multiple phenotype setting. We also investigate the power of three other popular statistical methods, the Wald test, the variance component test and the minimum $p$-value test, in both multiple phenotype and SNP-set settings. We use theoretical power, simulation studies, and two real data analyses to validate our findings.




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High on the hill : the people of St Philip & St James Church, Old Noarlunga / City of Onkaparinga.

St. Philip and St. James Church (Noarlunga, S.A.)




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High on the hill : the people of St Philip & St James Church, Old Noarlunga%cCity of Onkaparinga.

St. Philip and St. James Church (Noarlunga, S.A.)




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A Bayesian Nonparametric Multiple Testing Procedure for Comparing Several Treatments Against a Control

Luis Gutiérrez, Andrés F. Barrientos, Jorge González, Daniel Taylor-Rodríguez.

Source: Bayesian Analysis, Volume 14, Number 2, 649--675.

Abstract:
We propose a Bayesian nonparametric strategy to test for differences between a control group and several treatment regimes. Most of the existing tests for this type of comparison are based on the differences between location parameters. In contrast, our approach identifies differences across the entire distribution, avoids strong modeling assumptions over the distributions for each treatment, and accounts for multiple testing through the prior distribution on the space of hypotheses. The proposal is compared to other commonly used hypothesis testing procedures under simulated scenarios. Two real applications are also analyzed with the proposed methodology.




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Response of Neurons in the Lateral Intraparietal Area during a Combined Visual Discrimination Reaction Time Task

Jamie D. Roitman
Nov 1, 2002; 22:9475-9489
Behavioral




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The analysis of visual motion: a comparison of neuronal and psychophysical performance

KH Britten
Dec 1, 1992; 12:4745-4765
Articles




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The Right Temporoparietal Junction Is Causally Associated with Embodied Perspective-taking

A prominent theory claims that the right temporoparietal junction (rTPJ) is especially associated with embodied processes relevant to perspective-taking. In the present study, we use high-definition transcranial direct current stimulation to provide evidence that the rTPJ is causally associated with the embodied processes underpinning perspective-taking. Eighty-eight young human adults were stratified to receive either rTPJ or dorsomedial PFC anodal high-definition transcranial direct current stimulation in a sham-controlled, double-blind, repeated-measures design. Perspective-tracking (line-of-sight) and perspective-taking (embodied rotation) were assessed using a visuo-spatial perspective-taking task that required understanding what another person could see or how they see it, respectively. Embodied processing was manipulated by positioning the participant in a manner congruent or incongruent with the orientation of an avatar on the screen. As perspective-taking, but not perspective-tracking, is influenced by bodily position, this allows the investigation of the specific causal role for the rTPJ in embodied processing. Crucially, anodal stimulation to the rTPJ increased the effect of bodily position during perspective-taking, whereas no such effects were identified during perspective-tracking, thereby providing evidence for a causal role for the rTPJ in the embodied component of perspective-taking. Stimulation to the dorsomedial PFC had no effect on perspective-tracking or taking. Therefore, the present study provides support for theories postulating that the rTPJ is causally involved in embodied cognitive processing relevant to social functioning.

SIGNIFICANCE STATEMENT The ability to understand another's perspective is a fundamental component of social functioning. Adopting another perspective is thought to involve both embodied and nonembodied processes. The present study used high-definition transcranial direct current stimulation (HD-tDCS) and provided causal evidence that the right temporoparietal junction is involved specifically in the embodied component of perspective-taking. Specifically, HD-tDCS to the right temporoparietal junction, but not another hub of the social brain (dorsomedial PFC), increased the effect of body position during perspective-taking, but not tracking. This is the first causal evidence that HD-tDCS can modulate social embodied processing in a site-specific and task-specific manner.




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Christine Lagarde: Interview in Le Parisien

Interview with Ms Christine Lagarde, President of the European Central Bank, and Le Parisien, conducted by Mr Matthieu Pelloli and published on 9 April 2020.