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Reliable remote cognitive testing could provide a safer assessment of cognitive impairment in multiple sclerosis (MS) during the COVID-19 pandemic and thereafter. Here we aimed to investigate the reliability and feasibility of administering Brief International Cognitive Assessment for MS (BICAMS) and the Trail-Making Test (TMT) to people with MS online. Between-group differences on BICAMS and the TMT were examined in a sample of 68 participants. Group 1 (N = 34) was tested in-person pre-pandemic. Group 2 was tested remotely. Within-group differences for in-person and virtual administrations were examined for Group 1. No significant differences between virtual and in-person administrations of the CVLT-II and SDMT were detected. BVMT-R scores were significantly higher for virtual administrations (M = 20.59, SD = 6.65) compared to in-person administrations (M = 16.35, SD = 6.05), possibly indicating inter-rater differences. Strong positive correlations were found for in-person and virtual scores within Group 1 on the CVLT-II (r = .84), SDMT (r = .85), TMT-A (r = .88), TMT-B (r = .76) and BVMT-R (r = .72). No significant differences between in-person and remote administrations of CVLT-II and SDMT in people living with MS were detected. Recommendations for future studies employing the TMT and BVMT-R online are provided. This study-within-a-trial was conducted within a trial funded by the Health Research Board (Ireland) under a Definitive Interventions and Feasibility Award [grant number DIFA-FA-2018-027]. peer-reviewed

In some problem spaces, the high cost of obtaining ground truth labels necessitates use of lower quality reference datasets. It is difficult to benchmark model performance using these datasets, as evaluation results may be biased. We propose a supplement to using reference labels, which we call an approximate ground truth refinement (AGTR). Using an AGTR, we prove that bounds on specific metrics used to evaluate clustering algorithms and multi-class classifiers can be computed without reference labels. We also introduce a procedure that uses an AGTR to identify inaccurate evaluation results produced from datasets of dubious quality. Creating an AGTR requires domain knowledge, and malware family classification is a task with robust domain knowledge approaches that support the construction of an AGTR. We demonstrate our AGTR evaluation framework by applying it to a popular malware labeling tool to diagnose over-fitting in prior testing and evaluate changes whose impact could not be meaningfully quantified under previous data., to appear in Proceedings of the 14th ACM Workshop on Artificial Intelligence and Security

We present an overview of the field of malware analysis with emphasis on issues related to document engineering. We will introduce the field with a discussion of the types of malware, including executable binaries, malicious PDFs, polymorphic malware, ransomware, and exploit kits. We will conclude with our view of important research questions in the field. This is an updated version of last year's tutorial, with more information about web-based malware and malware targeting the Android market.

The Australian Defence Science and Technology Group have developed novel single photon avalanche diode (SPAD) arrays using Silicon based complementary metal-oxide semiconductor (CMOS) processes. The first of these was a simple 32x32 pixel array, followed by higher density arrays developed with our partners. These single photon detector arrays have inherently low dark currents and we have used them in several Flash LADAR systems, including an innovative design where the LADAR is cued by an 8-12 micron infrared imager which shares a common aperture. The use of Flash LADAR (rather than scanning) has the advantage that moving targets can be imaged accurately. We have developed modelling and simulation tools for predicting SPAD LADAR performance and use processing techniques to suppress ‘background’ counts and resolve targets that are obscured by clutter. In this paper we present some of our initial results in discriminating small (

We have developed a tool to extract the contents of volatile memory of Apple Macs running recent versions of OS X, which has not been possible since OS X 10.4. This paper recounts our efforts to test the tool and introduces two visualization techniques for that purpose. We also introduce four metrics for evaluating physical memory imagers: correctness, completeness, speed, and the amount of ''interference'' an imager makes to the state of the machine. We evaluate our tool by these metrics and then show visualization using dotplots, a technique borrowed from bioinformatics, can be used to reveal bugs in the implementation and to evaluate correctness, completeness, and the amount of interference an imager has. We also introduce a visualization we call the density plot which shows the density of repeated pages at various addresses within an image. We use these techniques to evaluate our own tool, Apple's earlier tools, and compare physical memory images to the hibernation file.

Rabits with Streptococcus viridans aortic valve endocarditis develop anaemia and reticulocytosis which increase with the duration of infection. Mean red cell counts decreased from 6.05 +/- 0.29 X 10(6) per mul before infection to 4.10 +/- 0.18 X 10(6) per mul after 11 to 20 days of endocarditis and reticulocytes increased from 1.16 +/- 0.14 X 10(5) per mul to 4.91 +/- 0.83 X 10(5) per mul after more than 20 days of endocarditis. The anaemia could not be explained by intravascular haemolysis. Anti-erythrocyte antibodies were not detected. Splenomegaly was a consistent finding and also increased with the duration of infection. Red cell half life (T1/2) was shortened to 4.7 +/- 0.3 days in rabbits with endocarditis compared with normal T1/2 of 11.1 +/- 0.5 days. The T1/2 of red cells from infected animals was prolonged when measured in noninfected rabbits and splenectomized animals had a mean red cell T1/2 of 9.25 days after three weeks of infection. These studies suggest that splenic enlargement associated with infection results in red cell sequestration, a mechanism not well recognized as contributing to the anaemia of endocarditis.

Computer forensic tools for Apple Mac hardware have traditionally focused on low-level file system details. Mac OS X and common applications on the Mac platform provide an abundance of information about the user's activities in configuration files, caches, and logs. We are developing MEGA, an extensible tool suite for the analysis of files on Mac OS X disk images. MEGA provides simple access to Spotlight metadata maintained by the operating system, yielding efficient file content search and exposing metadata such as digital camera make and model. It can also help investigators to assess FileVault encrypted home directories. MEGA support tools are under development to interpret files written by common Mac OS applications such as Safari, Mail, and iTunes.

Digital forensic investigators often find peer-to-peer, or file sharing, software present on the computers, or the images of the disks, that they examine. Investigators must first determine what P2P software is present and where the associated information is stored, retrieve the information from the appropriate directories, and then analyze the results. File Marshal is a tool that will automatically detect and analyze peer-to-peer client use on a disk. The tool automates what is currently a manual and labor intensive process. It will determine what clients currently are or have been installed on a machine, and then extracts per-user usage information, specifically a list of peer servers contacted, and files that were shared and downloaded. The tool was designed to perform its actions in a forensically sound way, including maintaining a detailed audit trail of all actions performed. File Marshal is extensible, using a configuration file to specify details about specific peer-to-peer clients (e.g., location of log files and registry keys indicating installation). This paper describes the general design and features of File Marshal, its current status, and the plans for continued development and release. When complete, File Marshal, a National Institute of Justice funded effort, will be disseminated to law enforcement at no cost.

Since 1997 there has been increasing interest in the development of analytical methods for the analysis of perchlorate. The US Environmental Protection Agency (EPA) Method 314.0, which was used during the first Unregulated Contaminant Monitoring Regulation (UCMR) cycle, supports a method reporting limit (MRL) of 4.0 microg/L. The non-selective nature of conductivity detection, combined with very high ionic strength matrices, can create conditions that make the determination of perchlorate difficult. The objective of this work was to develop an automated, suppressed conductivity method with improved sensitivity for use in the second UCMR cycle. The new method, EPA Method 314.1, uses a 35 mm x 4 mm cryptand concentrator column in the sample loop position to concentrate perchlorate from a 2 mL sample volume, which is subsequently rinsed with 10 mM NaOH to remove interfering anions. The cryptand concentrator column is combined with a primary AS16 analytical column and a confirmation AS20 analytical column. Unique characteristics of the cryptand column allow perchlorate to be desorbed from the cryptand trap and refocused on the head of the guard column for subsequent separation and analysis. EPA Method 314.1 has a perchlorate lowest concentration minimum reporting level (LCMRL) of 0.13 microg/L in both drinking water and laboratory synthetic sample matrices (LSSM) containing up to 1,000 microg/L each of chloride, bicarbonate and sulfate.

Two algorithms are presented for the detection of gradual transitions in video sequences. The first is a dissolve detection algorithm utilizing certain properties of a dissolve's trajectory in image-space. It is implemented both as a simple threshold-based detector, and as a parametric detector by modeling the error properties of the extracted statistics. The second is an algorithm to detect a wide variety of wipes based on image histogram characteristics during such transitions. Both algorithms operate in the compressed domain, requiring only partial decoding of the compressed video stream. Experiments show the algorithms perform as well as-and in some cases, better than-full-frame methods, on a wide variety of gradual transitions, and can operate significantly faster than real-time.

We apologize unreservedly to the authors for the poor quality of the reproduction of the figures in their paper. These are now reproduced in the form in which they were originally intended.

An ion chromatographic method was developed for the determination of nine inorganic and organic acid anions at sub- to low-microg/l levels in power plant water samples. In this method, samples were injected using a large-volume direct injection technique, the analyte anions were separated on a hydroxide-selective anion-exchange column using high-purity hydroxide eluents generated by an on-line electrolytic eluent generator and detected using the suppressed conductivity detection method. The method performance was evaluated by analyzing synthetic water samples containing additives encountered in the power plant water samples and four water samples from a fossil fuel power plant. The relative standard deviations of retention times of analyte ions separated on the hydroxide-selective anion-exchange column were less than 0.4%. The recoveries of analyte ions spiked into the synthetic water samples at concentrations of 0.13-1.0 microg/l were in the range of 70-120%. The method detection limits for analyte ions in deionized water were 0.0099, 0.0056, 0.019, 0.057, 0.0084, 0.023, 0.067, 0.037, and 0.079 microg/l for fluoride, acetate, formate, chloride, nitrite, sulfate, bromide, nitrate, and phosphate, respectively.

The reliable and efficient transmission of high-quality variable bit rate (VBR) video through the Internet generally requires network resources be allocated in a dynamic fashion. This includes the determination of when to renegotiate for network resources, as well as how much to request at a given time. The accuracy of any resource request method depends critically on its prediction of future traffic patterns. Such a prediction can be performed using the content and traffic information of short video segments. This paper presents a systematic approach to select the best features for prediction, indicating that while content is important in predicting the bandwidth of a video hit stream, the use of both content and available short-term bandwidth statistics can yield significant improvements. A new framework for traffic prediction is proposed in this paper; experimental results show a smaller mean-square resource prediction error and higher overall link utilization.

A new enhanced resistor array projector nonuniformity correction (NUC) process based on the flood method is presented. It relies on precise characterisation of the projector-camera optical system. The information obtained from the characterisation procedure is used for the rapid derivation of NUC coefficients in a minimal number of iterations. The new NUC process benefits from using large format cameras but, in contrast to previous flood methods, it does not depend critically on 1:1 mapping and can be performed using smaller format cameras. Other benefits are improved handling of emitter array imperfections and sampling artefacts. The procedure is fast and alleviates camera temporal effects such as drift. In order to further isolate the correction process from temporal effects, we have implemented a new multi-point multi-temperature camera calibration procedure that allows the corrections to be applied in real time. We describe our procedure and discuss other possible NUC improvement strategies.

A collaborative study was conducted by the U.S. Environmental Protection Agency (U.S. EPA) and the American Society for Testing Materials (ASTM) on an ion chromatographic method for the determination of hexavalent chromium (U.S. EPA method 218.6, and the ASTM equivalent method). This study was designed to determine the mean recovery and precision of analyses for hexavalent chromium in reagent water, drinking water, groundwater, and industrial wastewaters. The study design was based on Youden’s nonreplicate plan for collaborative studies of analytical methods. The test waters were spiked with hexavalent chromium at 8 concentration levels, prepared as 4 Youden pairs. A fifth Youden concentration pair was also included to determine method performance close to the method detection limit. Twenty-one laboratories were instructed to filter their test waters through a 0.45 μm filter and to adjust the pH of the filtrate to 9–9.5 with an ammonium sulfate/ammonium hydroxide buffer solution before spiking with the hexavalent chromium concentrates. A known volume, 50–250 (μL, was injected into an ion chromatograph which separated the Cr(VI), as CrO42−, on an anion exchange column. After separation, the Cr(VI) was derivatized with diphenylcarbazide and the colored complex was detected at 530 nm. The submitted data were corrected for background concentrations and analyzed by applying ASTM D-2777-86 statistical procedures and a U.S. EPA computer program. U.S. EPA method 218.6 and the equivalent ASTM method were judged acceptable for the measurement of hexavalent chromium concentrations at 1–1000 μg Cr(VI)/L. The study found that the use of a single linear calibration extending over 3 orders of magnitude yielded biased results at the very lowest concentration levels. Shorter range calibration curves yielded more accurate results. Analysis of variance (ANOVA) tests indicated that method performance was significantly different between the reagent water matrix and the other matrixes used. The recovery of Cr(VI) from the other matrixes was lower at all concentration levels with slightly less precision when compared with the reagent water data set. For reagent water, the mean recovery and the overall and single-analyst relative standard deviations were 105%, 7.8% and 3.9%, respectively. For the other matrixes, the same values were 96.7%, 11.9% and 6.3%, respectively. The method was adopted first action by AOAC INTERNATIONAL.

Bromate is one of the disinfection by-products produced by the ozonation of drinking water. The US Environmental Protection Agency is considering regulating bromate to the low μg/l level. A method using ion chromatography has been developed which will quantify bromate at this level, even in the presence of high (mg/l) levels of common anions such as chloride and sulfate. A borate eluent system was used to improve the separation of bromate from chloride. The level of chloride in the sample was reduced by pretreating the sample using a silver- form cation-exchange resin. The lower chloride level allowed a larger sample volume and preconcentration which reduced the bromate method detection limit to 1 μg/l.

Functional analyses were performed on neutrophils isolated from 6 patients from two institutions who displayed features of chronic neutrophilic leukemia (CNL). These neutrophils demonstrated a consistent deficiency (44 +/- 8% of control values) in superoxide anion (O2-) production in response to the phorbol ester, phorbol myristate acetate (PMA). O2- production in response to chemotactic peptides was near normal (82.3 +/- 10.7% of control values). Bacterial killing was normal in the two patients studied, and chemotaxis was diminished in response to zymosan-activated plasma and to high concentrations of chemotactic peptides in the patients studied. Cytosolic C kinase activity was decreased in one of the two patients studied. These results suggest that a deficient O2- release in response to PMA is a hallmark of neutrophils in CNL and may provide a diagnostic indicator of this condition.

The concept of milling obstructions in wellbores, utilizing electric wireline as a means to deploy the service, was introduced in 2005. Since that time, oil and gas operators around the globe have used this well intervention technique efficiently and cost effectively. These wireline-conveyed technologies have performed well in both completion and workover programs by providing the means to drill out stuck isolation or safety valves, remove non-retrievable plugs and re-establish production by removing scale. The additional cost of lost or deferred production is always unwanted. The deployment of a traditional rig or coiled tubing unit to help restore production comes with considerable cost owing to the equipment and personnel requirements to operate these heavy equipment platforms. Consequently, operators continually look to new techniques to minimize this burden. Milling on electric wireline, where applicable, is one such technique since it can be offered within a rig-less environment. Experience has shown that each and every new milling challenge requires careful study of the problem along with extensive planning, testing and verification of the technique. Every downhole scenario provides a different characteristic to consider. As a result, many man-hours and research dollars are required to provide solutions for advanced milling projects. This paper presents new applications for electric-wireline milling. First, a summary of the milling experience to date will be presented followed by the examination of some complex milling challenges through several unique case studies and verification tests. Value statements are also presented for each case study.