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On Multistage Adaptive Biomarker-Directed Clinical Trial Design
No full textBiomarker-directed targeted designs have been developed in recent years for pharmaceutical development for patient subpopulation with specific disease etiology. Multistage testing and adaption are desired for targeted designs to manage the risk of study population deviation, to conduct interim analysis and to make decisions on stochastic curtailment. We propose a multistage adaptive design for targeted trials that allows flexibility in multistage testing, stochastic curtailment decision-making, biomarker performance monitoring and biomarker performance-based sample size adaption. The design is based on the theorem that the sequence of test statistics from multistage testings asymptotically satisfies Brownian motion in different targeted trial settings. The theorem is proven for both continuous and binary endpoints. The simulation analysis has indicated that targeted multistage designs perform better than its untargeted counterpart in trial efficiency, effective information accumulation and stochastic curtailment decision-making by selecting targeted patients. However, this study has shown that biomarker performance influences heterogeneity of targeted study population and consequently affects planning and multistage testing of a targeted trial. The impact of biomarker performance has been extensively examined with regard to study efficiency, actual statistical power, type-I error, information accrument, and stochastic curtailment decision-making. To cope with the limited information of biomarker performance at study planning, we propose the biomarker performance-based sample size adaption for targeted trials for continuous and binary endpoints, respectively. The adaptive method can update actual biomarker performance at interim analysis and re-estimate sample size to achieve planned statistical power while preserving type-I error rate. In summary, the multistage adaptive design improves targeted trials by providing great flexibility in multistage testing, early stopping, biomarker performance monitoring and biomarker performance-based sample size adaption
An Energy Efficient Rate Adaptive Distributed Source Coding Algorith: RSWITCH
No full textCurrent strategies for estimating correlation among multiple sources typically require an unsupported degree of network bandwidth or significant computational resources required by the receiver. A novel strategy that does not suffer from these weaknesses is desirable and is a current topic of research in distributed source coding theory. A novel source correlation algorithm, RSWITCH, is presented that both minimizes network bandwidth and required computational resources beyond that given by the state of the art
The Relation Between Parent Distraction Behaviors and Child Distress During Pediatric Cancer Procedures
No full textThis study examined the relation between child distress, parent distraction behaviors, and parent other nonprocedural talk during pediatric cancer procedures. Participants were 72 children with cancer (age 5 to 13 years old) and their mothers. Cancer procedures were videotaped and coded for parent behaviors and child distress. Contrary to hypotheses, child distress was positively related to parent verbal distraction and nonprocedural talk to the child and negatively related to nonprocedural talk to another adult in the room. Sequential analyses suggested that verbal distraction and nonprocedural talk to the child were more likely to occur after crying, while nonprocedural talk to another adult was less likely to occur after crying. Crying was less likely to occur after nonprocedural talk to another adult. Results suggest that nonprocedural talk to another adult functions differently than nonprocedural talk to the child; however, given the low frequency of behaviors, results should be interpreted with caution
A Decadal Gridded Hyperspectral Infrared Record for Climate. Sep 1st 2002 - Aug 31st 2012
No full textWe present a gridded Fundamental Decadal Data Record (FDDR) of Brightness Temperatures (BT) from the NASA Atmospheric Infrared Sounder (AIRS) from ten years of hyperspectral Infrared Radiances onboard the NASA EOS Aqua satellite. Although global surface temperature data records are available for over 130 years, it was not until 1978 when the Microwave Sounding Unit (MSU) was the first instrument series to reliably monitor long-term trends of the upper atmosphere. AIRS, operational on September 1, 2002 is the first successful hyperspectral satellite weather instrument of more than 1 year, and provides a 10 year global hyperspectral IR radiance data record. Our contribution was to prepare a gridded decadal data record of climate resolution from the AIRS Outgoing Longwave Spectrum (OLS). In order to do this, we developed a robust software infrastructure "Gridderama" using large multivariate array storage to facilitate this multi-terabyte parallel data processing task while ensuring integrity, tracking provenance, logging errors, and providing extensive visualization. All of our data, code, logs and visualizations are freely available online and browsable via a real-time "Data Catalog" interface. We show that these global all-sky trends are consistent with the expected radiative forcings from an increase in greenhouse gasses. We have also measured high global correlations with the GISS global surface air temperatures as well as high regional anticorrelations with the NOAA ONI index of El Niño phase. In addition, we have performed inter-annual inter-comparisons with the Moderate Resolution Spectro-radiometer (MODIS) on the same Aqua satellite to examine the relative consistency of their calibrations. The comparisons of the two instruments for the 4µ spectral channels (between 3.9µ and 4.1µ) indicate an inter-annual warming of 0.13K per decade of AIRS more than MODIS. This decadal relative drift is small compared to inter-annual variability but on the order of historic surface temperature trends. In the 12µ window channels (between 11.5µ and 12.5µ), AIRS - MODIS exhibits a standard deviation of 0.01K over a decade suggesting that the AIRS longwave has remained extremely well calibrated. This relative calibration result is to first order consistent with a recent radiometric comparison by H. Aumann et al. (2012) against pacific sea surface temperatures [19]. It is convenient to observe the climate variability by using monthly average lat-lon grid projections, but gridding is a lossy process that invariably introduces aliasing artifacts and noise. We observed an exponential decay between the number of days averaged and the expected noise due to gridding. We have extended the Observation Coverage (Obscov) gridding algorithm developed for the MODIS instrument that incorporates the Point Spread Function (PSF), and we show that the Obscov gridding algorithm reduces the aliasing noise from AIRS grids by nearly 40% by comparing the spatial correlation of gridded MODIS IR data. We also show that the use of a circular approximate PSF is a sufficient representation to obtain the noise reduction of Obscov at the climate resolution 0.5x1 degree monthly average grids. We extended these spatial sampling methods to the AIRS Level 3 retrieval records for which quality filtering due to opaque clouds is an additional spatial sampling challenge, and corrected an observed dry sampling bias in the AIRS v5 and v6 Level 3 monthly average gridded moisture retrieval records by means of spatial interpolation with the Nearest Neighbor (NN) and Ordinary Kriging (OK) strategies
Making English Grammar Meaningful and Useful Mini Lesson #5
No full textHelping Verbs, Communicative, English GrammarThis lesson was developed by John Nelson and Tymofey Wowk, 2012
Making English Grammar Meaningful and Useful
Mini Lesson #5
Helping Verbs – 5 Communicative Functions
The purpose of this lesson is to illustrate how Helping Verbs are used in informal conversational English.
Helping Verbs have 5 important Communicative Purposes. They are briefly described here with a few examples.
Short Answers – In conversational English, yes/no questions are rarely answered with complete sentences. Instead, whether the answer is positive or negative, it usually consists of yes or no, a subject and a Helping Verb.
Question Answer
“Is it raining outside?” “Yes, it is!”
“Do they often miss your class?” “No, they don’t!”
“Have the students bought their books?” “Yes, they have!”
“Did we cover that in class last week?” “No, we didn’t!”
Tag Questions – These short questions added to the end of statements are used for agreement or expected information. They are formed with a Helping Verb plus the subject of the sentence to which they are attached. A positive statement will have a negative tag; a negative statement will have a positive tag. The subject of the tag is usually a pronoun.
Statement Tag
“They wrote difficult items, didn’t they?”
“We won’t miss very many, will we?”
“She hasn’t finished her test, has she?”
“You have finished your test, haven’t you?”
Agreement/Disagreement – English has several ways for a responder to either agree or disagree with something that someone else has said. They nearly all use Helping Verbs. Positive agreements use ‘so’ or ‘too’. Negative agreements use ‘neither’ or ‘either’. Disagreements use only a subject pronoun and a Helping Verb.
Statement Agreement Disagreement
“I like spicy food.” “I do too.” “I don’t.”
“He writes well.” “So does she.” “She doesn’t.”
“He won’t go.” “Neither will she.” “She will.”
“She hasn’t finished.” “I haven’t either.” “I have.”
This lesson was developed by John Nelson and Tymofey Wowk, 2012
Surprise/Doubt – To express surprise or doubt about a statement, a responder formulates a short question using a subject with a Helping Verb, with or without using subject-verb inversion. Unlike tag questions, to show surprise for a positive statement, the response question is also positive. To show surprise for a negative statement, the response question is also negative.
Statement Response Question
“I always get A’s on my papers!” “Do you?!” or “You do?!”
“They got perfect test scores!” “Did they?!” or “They did?!”
“He hasn’t turned in his paper yet!” “Hasn’t he?!” or “He hasn’t?!”
“She won’t be able to come to class!” “Wont’ she?!” or “She won’t?!”
Emphasis – When a speaker wants to provide emphasis to a point, he/she will stress a Helping Verb to do so, and will insert a Helping Verb for this purpose if necessary.
Normal Statement Emphasized Statement
“They speak a little English.” “They do speak a little English!”
“It rained a bit last night.” “It did rain a bit last night!”
“I have done my homework.” “I have done my homework!”
“They will speak at 7:00.” “They will speak at 7:00!”
As illustrated here, Helping Verbs constitute an important aspect of English Grammar, and are used in many common conversational expressions. They should be the focus of direct instruction for ELLs. Drawing ELLs’ attention directly to Helping Verbs will provide them with a much better ability to function in English conversations naturally. This will also enable ELLs to understand and use English tenses more consistently, and how to ask and answer questions more accurately. Mastering Helping Verbs will enable ELLs to produce English sentences more correctly both in speech and in writing