Database Streaming Compression on Memory-Limited Machines

Dynamic Huffman compression algorithms operate on data-streams with a bounded symbol list. With these algorithms, the complete list of symbols must be contained in main memory or secondary storage. A horizontal format transaction database that is streaming can have a very large item list. Many nodes tax both the processing hardware primary memory size, and the processing time to dynamically maintain the tree. This research investigated Huffman compression of a transaction-streaming database with a very large symbol list, where each item in the transaction database schema’s item list is a symbol to compress. The constraint of a large symbol list is, in this research, equivalent to the constraint of a memory-limited machine. A large symbol set will result if each item in a large database item list is a symbol to compress in a database stream. In addition, database streams may have some temporal component spanning months or years. Finally, the horizontal format is the format most suited to a streaming transaction database because the transaction IDs are not known beforehand This research prototypes an algorithm that will compresses a transaction database stream. There are several advantages to the memory limited dynamic Huffman algorithm. Dynamic Huffman algorithms are single pass algorithms. In many instances a second pass over the data is not possible, such as with streaming databases. Previous dynamic Huffman algorithms are not memory limited, they are asymptotic to O(n), where n is the number of distinct item IDs. Memory is required to grow to fit the n items. The improvement of the new memory limited Dynamic Huffman algorithm is that it would have an O(k) asymptotic memory requirement; where k is the maximum number of nodes in the Huffman tree, k \u3c n, and k is a user chosen constant. The new memory limited Dynamic Huffman algorithm compresses horizontally encoded transaction databases that do not contain long runs of 0’s or 1’s

Archeological Survey Of The Proposed Capitol Parks Little League Ball Fields, San Antonio, Bexar County, Texas

On April 10 and June 6, 2018, personnel with Prewitt and Associates, Inc., conducted an intensive archeological survey on 23.7 acres of undeveloped land to be utilized for the creation new Little League baseball fields just east of the intersection of Wurzbach Parkway and Wetmore Road in northeast San Antonio, Texas. This survey was conducted under the direction of Adams Environmental, Inc., for Cude Engineers, partially under Texas Antiquities Permit No. 8379. The proposed development will be done as a private-public partnership. Most of the project area (23.0 acres) is privately owned land (Capitol Aggregates, Inc.). The public component of the project will involve use of City of San Antonio bond money to construct a road and bridge to access the property on its southeast side. This will be done on 0.7 acres of publicly owned land, and only this part of the project is governed by the terms of the antiquities permit. No prehistoric or historic artifacts or archeological sites were identified during the survey. The access bridge and road section has seen extensive disturbance from development along the eastern creek bank, and the main western section of the proposed park has seen disturbance associated with land clearing and the construction of embankments along Wurzbach Parkway. Shovel testing and examination of cut banks in this western section found no evidence of archeological sites. The proposed project will not impact any archeological resources that meet eligibility criteria for listing in the National Register of Historic Places or designation as a State Antiquities Landmark. Prewitt and Associates, Inc., recommends that the proposed project be allowed to proceed without additional archeological investigations

Melatonin as a potential therapy for sepsis : a phase I dose escalation study and an ex vivo whole blood model under conditions of sepsis

This article is protected by copyright. All rights reserved. This study was funded by the Chief Scientist Office, NHS Scotland. We would like to thank all the volunteers who gave up their time and blood to take part in the study and the data monitoring committee and staff of the intensive care unit for their support. In addition, thanks to Dr Malachy Columb for performing Page's trend test for us and to Annette Fearnley at Nu-Pharm Ltd for her advice.Peer reviewedPublisher PD

Deconstructing and Operationalizing Interactivity: An Online Advertising Perspective

In an online advertising context this empirical study examines the influence of the interface characteristic Interactivity on important user perceptions and their intention to use a website. Results indicate that social presence and telepresence are significant predictors of attitude toward online advertisements, satisfaction with online advertisements, and subsequent intentions to use a host website. Also indicated by this study is the significant influence of interactivity, as well as consumer involvement and the interaction between these two variables. The outcomes of this study offer preliminary insight into the conceptualization and affect of interface characteristics, such as interactivity, in online advertising

Simulation of Vertical Axis Wind Turbines With Variable Pitch Foils

A dynamic computer model of a turbine was developed in MATLAB in order to study the behavior of vertical axis wind turbines (VAWTs) with variable pitch (articulating) foils. The simulation results corroborated the findings of several empirical studies on VAWTs. The model was used to analyze theories of pitch articulation and to inform the discussion on turbine design. Simulations of various models showed that pitch articulation allowed Darrieus-style vertical axis wind turbines to start from rest. Once in motion, the rotor was found to accelerate rapidly to very high rotational velocities. The simulations revealed a plateau region of high efficiency for small-scale Darrieus-style VAWTs with symmetric airfoils at tip speed ratios in the range of 3 to 4 and demonstrated the advantages of using a dynamic generator load

A robust multivariate, non-parametric outlier identification method for scrubbing in fMRI

Functional magnetic resonance imaging (fMRI) data contain high levels of noise and artifacts. To avoid contamination of downstream analyses, fMRI-based studies must identify and remove these noise sources prior to statistical analysis. One common approach is the "scrubbing" of fMRI volumes that are thought to contain high levels of noise. However, existing scrubbing techniques are based on ad hoc measures of signal change. We consider scrubbing via outlier detection, where volumes containing artifacts are considered multidimensional outliers. Robust multivariate outlier detection methods are proposed using robust distances (RDs), which are related to the Mahalanobis distance. These RDs have a known distribution when the data are i.i.d. normal, and that distribution can be used to determine a threshold for outliers where fMRI data violate these assumptions. Here, we develop a robust multivariate outlier detection method that is applicable to non-normal data. The objective is to obtain threshold values to flag outlying volumes based on their RDs. We propose two threshold candidates that embark on the same two steps, but the choice of which depends on a researcher's purpose. Our main steps are dimension reduction and selection, robust univariate outlier imputation to get rid of the effect of outliers on the distribution, and estimating an outlier threshold based on the upper quantile of the RD distribution without outliers. The first threshold candidate is an upper quantile of the empirical distribution of RDs obtained from the imputed data. The second threshold candidate calculates the upper quantile of the RD distribution that a nonparametric bootstrap uses to account for uncertainty in the empirical quantile. We compare our proposed fMRI scrubbing method to motion scrubbing, data-driven scrubbing, and restrictive parametric multivariate outlier detection methods

Statin therapy in critical illness : an international survey of intensive care physicians' opinions, attitudes and practice

Background Pleotropic effects of statins on inflammation are hypothesised to attenuate the severity of and possibly prevent the occurrence of the host inflammatory response to pathogen and infection-related acute organ failure. We conducted an international survey of intensive care physicians in Australia, New Zealand (ANZ) and United Kingdom (UK). The aims of the survey were to assess the current prescribing practice patterns, attitudes towards prescribing statin therapy in critically ill patients and opinions on the need for an interventional trial of statin therapy in critically ill patients. Methods Survey questions were developed through an iterative process. An expert group reviewed the resulting 26 items for face and content validity and clarity. The questions were further refined following pilot testing by ICU physicians from Australia, Canada and the UK. We used the online Smart SurveyTM software to administer the survey. Results Of 239 respondents (62 from ANZ and 177 from UK) 58% worked in teaching hospitals; most (78.2%) practised in ‘closed’ units with a mixed medical and surgical case mix (71.0%). The most frequently prescribed statins were simvastatin (77.6%) in the UK and atorvastatin (66.1%) in ANZ. The main reasons cited to explain the choice of statin were preadmission prescription and pharmacy availability. Most respondents reported never starting statins to prevent (65.3%) or treat (89.1%) organ dysfunction. Only a minority (10%) disagreed with a statement that the risks of major side effects of statins when prescribed in critically ill patients were low. The majority (84.5%) of respondents strongly agreed that a clinical trial of statins for prevention is needed. More than half (56.5%) favoured rates of organ failure as the primary outcome for such a trial, while a minority (40.6%) favoured mortality. Conclusions Despite differences in type of statins prescribed, critical care physicians in the UK and ANZ reported similar prescription practices. Respondents from both communities agreed that a trial is needed to test whether statins can prevent the onset of new organ failure in patients with sepsis

An Empirical Evaluation of the US Beer Institute’s Self-Regulation Code Governing the Content of Beer Advertising

Objectives. We evaluated advertising code violations using the US Beer Institute guidelines for responsible advertising. Methods. We applied the Delphi rating technique to all beer ads (n = 289) broadcast in national markets between 1999 and 2008 during the National Collegiate Athletic Association basketball tournament games. Fifteen public health professionals completed ratings using quantitative scales measuring the content of alcohol advertisements (e.g., perceived actor age, portrayal of excessive drinking) according to 1997 and 2006 versions of the Beer Institute Code. Results. Depending on the code version, exclusion criteria, and scoring method, expert raters found that between 35% and 74% of the ads had code violations. There were significant differences among producers in the frequency with which ads with violations were broadcast, but not in the proportions of unique ads with violations. Guidelines most likely to be violated included the association of beer drinking with social success and the use of content appealing to persons younger than 21 years. Conclusions. The alcohol industry’s current self-regulatory framework is ineffective at preventing content violations but could be improved by the use of new rating procedures designed to better detect content code violations

Production and Processing of siRNA Precursor Transcripts from the Highly Repetitive Maize Genome

Mutations affecting the maintenance of heritable epigenetic states in maize identify multiple RNA–directed DNA methylation (RdDM) factors including RMR1, a novel member of a plant-specific clade of Snf2-related proteins. Here we show that RMR1 is necessary for the accumulation of a majority of 24 nt small RNAs, including those derived from Long-Terminal Repeat (LTR) retrotransposons, the most common repetitive feature in the maize genome. A genetic analysis of DNA transposon repression indicates that RMR1 acts upstream of the RNA–dependent RNA polymerase, RDR2 (MOP1). Surprisingly, we show that non-polyadenylated transcripts from a sampling of LTR retrotransposons are lost in both rmr1 and rdr2 mutants. In contrast, plants deficient for RNA Polymerase IV (Pol IV) function show an increase in polyadenylated LTR RNA transcripts. These findings support a model in which Pol IV functions independently of the small RNA accumulation facilitated by RMR1 and RDR2 and support that a loss of Pol IV leads to RNA Polymerase II–based transcription. Additionally, the lack of changes in general genome homeostasis in rmr1 mutants, despite the global loss of 24 nt small RNAs, challenges the perceived roles of siRNAs in maintaining functional heterochromatin in the genomes of outcrossing grass species