The Application of Quaternions to Strap-Down MEMS Sensor Data.

We describe the mathematical transformations required to convert the data recorded using typical 6-axis microelectromechanical systems (MEMS) sensor packages (3-axis rate gyroscopes and 3-axis accelerometers) when attached to an object undergoing a short duration loading event, such as blast loading, where inertial data alone are sufficient to track the object motion. By using the quaternion description, the complex object rotations and displacements that typically occur are translated into the more convenient earth frame of reference. An illustrative example is presented where a large and heavy object was thrown by the action of a very strong air blast in a complex manner. The data conversion process yielded an accurate animation of the object's subsequent motion.

Opinions of former jail residents about self-collection of SARS-CoV-2 specimens, paired with wastewater surveillance: A qualitative study rapidly examining acceptability of COVID-19 mitigation measures.

In year one of the COVID-19 epidemic, the incidence of infection for US carceral populations was 5.5-fold higher than that in the community. Prior to the rapid roll out of a comprehensive jail surveillance program of Wastewater-Based Surveillance (WBS) and individual testing for SARS-CoV-2, we sought the perspectives of formerly incarcerated individuals regarding mitigation strategies against COVID-19 to inform acceptability of the new program. In focus groups, participants discussed barriers to their receiving COVID-19 testing and vaccination. We introduced WBS and individual nasal self-testing, then queried if wastewater testing to improve surveillance of emerging outbreaks before case numbers surged, and specimen self-collection, would be valued. The participants' input gives insight into ways to improve the delivery of COVID-19 interventions. Hearing the voices of those with lived experiences of incarceration is critical to understanding their views on infection control strategies and supports including justice-involved individuals in decision-making processes regarding jail-based interventions.

Coping with COVID in corrections: a qualitative study among the recently incarcerated on infection control and the acceptability of wastewater-based surveillance.

BACKGROUND: Correctional settings are hotspots for SARS-CoV-2 transmission. Social and biological risk factors contribute to higher rates of COVID-19 morbidity and mortality among justice-involved individuals. Rapidly identifying new cases in congregate settings is essential to promote proper isolation and quarantine. We sought perspectives of individuals incarcerated during COVID-19 on how to improve carceral infection control and their perspectives on acceptability of wastewater-based surveillance (WBS) accompanying individual testing. METHODS: We conducted semi-structured interviews with 20 adults who self-reported being incarcerated throughout the United States between March 2020 and May 2021. We asked participants about facility enforcement of the Centers for Disease Control and Prevention (CDC) COVID-19 guidelines, and acceptability of integrating WBS into SARS-CoV-2 monitoring strategies at their most recent facility. We used descriptive statistics to characterize the study sample and report on acceptability of WBS. We analyzed qualitative data thematically using an iterative process. RESULTS: Participants were predominantly Black or multiple races (50%) and men (75%); 46 years old on average. Most received a mask during their most recent incarceration (90%), although only 40% received counseling on proper mask wearing. A quarter of participants were tested for SARS-CoV-2 at intake. Most (70%) believed they were exposed to the virus while incarcerated. Reoccurring themes included (1) Correctional facility environment leading to a sense of insecurity, (2) Perceptions that punitive conditions in correctional settings were exacerbated by the pandemic; (3) Importance of peers as a source of information about mitigation measures; (4) Perceptions that the safety of correctional environments differed from that of the community during the pandemic; and (5) WBS as a logical strategy, with most (68%) believing WBS would work in the last correctional facility they were in, and 79% preferred monitoring SARS-CoV-2 levels through WBS rather than relying on just individual testing. CONCLUSION: Participants supported routine WBS to monitor for SARS-CoV-2. Integrating WBS into existing surveillance strategies at correctional facilities may minimize the impact of future COVID-19 outbreaks while conserving already constrained resources. To enhance the perception and reality that correctional systems are maximizing mitigation, future measures might include focusing on closer adherence to CDC recommendations and clarity about disease pathogenesis with residents.

ADH single nucleotide polymorphism associations with alcohol metabolism in vivo.

We have previously found that variation in alcohol metabolism in Europeans is linked to the chromosome 4q region containing the ADH gene family. We have now typed 103 single nucleotide polymorphisms (SNPs) across this region to test for allelic associations with variation in blood and breath alcohol concentrations after an alcohol challenge. In vivo alcohol metabolism was modelled with three parameters that identified the absorption and rise of alcohol concentration following ingestion, and the rate of elimination. Alleles of ADH7 SNPs were associated with the early stages of alcohol metabolism, with additional effects in the ADH1A, ADH1B and ADH4 regions. Rate of elimination was associated with SNPs in the intragenic region between ADH7 and ADH1C, and across ADH1C and ADH1B. SNPs affecting alcohol metabolism did not correspond to those reported to affect alcohol dependence or alcohol-related disease. The combined SNP associations with early- and late-stage metabolism only account for approximately 20% of the total genetic variance linked to the ADH region, and most of the variance for in vivo alcohol metabolism linked to this region is yet to be explained.

Association of the gastric alcohol dehydrogenase gene ADH7 with variation in alcohol metabolism.

Seven alcohol-metabolizing enzymes are encoded by the human alcohol dehydrogenase (ADH) gene cluster on chromosome 4q22-23. One of these genes, ADH7, is uniquely expressed in the stomach mucosa and can influence metabolism of alcohol before its absorption into the blood. However, the contribution of ADH7 to the overall genetic variation in alcohol oxidation in vivo is unknown. Data on in vivo alcohol metabolism were obtained for 206 Australian twin pairs of Caucasian ancestry, following ingestion of a standard dose (0.75 g kg(-1) body weight) of alcohol. Twenty-five single nucleotide polymorphisms that cover the ADH7 encoding region were genotyped. The patterns of linkage disequilibrium among these SNPs identified a recombinational hotspot within intron 7 of the ADH7 gene. A model for the absorption and elimination of alcohol from the body led to the identification of haplotypes associated with inter-individual variation in the early stages of alcohol metabolism. These are within a 35 kb DNA tract contained in the region 5' of intron 7 in the ADH7 gene. The region accounts for 18% of the linkage for alcohol concentration associated with the ADH region, or approximately 11% of the genetic variance.

Evaluation of multiple displacement amplification in a 5 cM STR genome-wide scan.

Multiple displacement amplification (MDA) has emerged as a promising new method of whole genome amplification (WGA) with the potential to generate virtually unlimited genome-equivalent DNA from only a small amount of seed DNA. To date, genome-wide high marker density assessments of MDA-DNA have focussed mainly upon suitability for single nucleotide polymorphism (SNP) genotyping applications. Suitability for short tandem repeat (STR) genotyping has not been investigated in great detail, despite their inherent instability during DNA replication, and the obvious challenge that this presents to WGA techniques. Here, we aimed to assess the applicability of MDA in STR genotyping by conducting a genome-wide scan of 768 STR markers for MDAs of 15 high quality genomic DNAs. We found that MDA genotyping call and accuracy rates were only marginally lower than for genomic DNA. Pooling of three replicate MDAs resulted in a small increase in both call rate and genotyping accuracy. We identified 34 STRs (4.4% of total markers) of which five essentially failed with MDA samples, and 29 of which showed elevated genotyping failures/discrepancies in the MDAs. We emphasise the importance of DNA and MDA quality checks, and the use of appropriate controls to identify problematic STR markers.

Estimation of the rate of SNP genotyping errors from DNA extracted from different tissues.

High density single nucleotide polymorphism (SNP) genotyping panels provide an alternative to microsatellite markers for genome scans. However, genotype errors have a major impact on power to detect linkage or association and are difficult to detect for SNPs. We estimated error rates with the Affymetrix GeneChip SNP platform in samples from a family with a mixed set of monozygotic (MZ) and dizygotic (DZ) triplets using lymphocyte, buccal DNA and samples from whole genome amplification using the multiple displacement amplification (MDA) technique. The average call rate from 58,960 SNPs for five genomic samples was 99.48%. Comparison of results for the MZ twins showed only three discordant genotypes (concordance rate 99.995%). The mean concordance rate for comparisons of samples from lymphocyte and buccal DNA was 99.97%. Mendelian inconsistencies were identified in 46 SNPs with errors in one or more family members, a rate of 0.022%. Observed genotype concordance rates between parents, between parents and children, and among siblings were consistent with previously reported allele frequencies and Hardy-Weinberg equilibrium. Using the MDA technique, results for two samples had equivalent high accuracy to results with genomic samples. However, the SNP call rate for the remaining seven samples varied from 72.5% to 99.5%, with an average of 86.11%. Quality of the DNA sample following the MDA reaction appears to be the critical factor in SNP call rate for MDA samples. Our results demonstrate highly accurate and reproducible genotyping for the Affymetrix GeneChip Human Mapping Set in lymphocyte and buccal DNA samples.

Primary care. The only way is up.

Despite posting the country's lowest score in 2004-05, the quality and outcomes framework of the new GMS contract has helped Bradford City teaching PCT focus and improve on key areas. The QOF is tough on deprived inner-city areas, where practices are often single-handed, with unsuitable premises and low levels of supporting staff. The introduction of practice-based action plans, as demonstrated in Bradford, could help inner-city practices score significantly better in 2005-06.

Note: A technique to capture and compose streak images of explosive events with unpredictable timing.

The authors describe a method to capture optical data and construct digitized streak images for analysis of high-speed phenomena with unpredictable timing by using a high-speed video camera and software routines. Advances in high-speed video camera technology have led to development of cameras with frame rates (1 x 10(6) frames per second) and spatial resolution (1280 x 800 pixels) suitable to capture fast phenomena, such as detonation in high explosives (< or = 10 km s(-1)), on small enough scales to be convenient for laboratory experiments. Further, relatively long-duration recordings (> or = 1 s) are maintained in a rolling buffer in volatile memory allowing the entire frame sequence to be recorded pretrigger, thus obviating the need for precisely located diagnostic triggers. The method described was used to capture the progression of luminous reaction during the deflagration-to-detonation transition of the HMX-based (octahydro-1, 3, 5, 7-tetranitro-1, 3, 5, 7-tetrazocine) plastic bonded explosive (PBX) formulation during cookoff.

The reliability of routine anthropometric data collected by health workers: a cross-sectional study.

BACKGROUND: Reliable data on child growth is a prerequisite for monitoring and improving child health. Despite the extensive resources invested in recording anthropometry, there has been little research into the reliability of these data. If these measurements are unreliable growth may be misreported, and health problems may go undetected. OBJECTIVES: To assess the reliability of routine infant growth data, following anthropometric training of health workers responsible for collecting these data, in Bradford, UK. To determine whether being observed by an external administrator influenced reliability. DESIGN: A test-retest design was used. PARTICIPANTS: All health workers (n=192) responsible for growth monitoring in Bradford were included in the study, of which 36.5% (n=70) had complete data. METHODS: Following training in basic anthropometry all health workers were asked to complete a test-retest study, using infants aged 0-2 years. Health workers took two recordings of weight, length, head circumference, and abdominal circumferences on five infants. A peer health worker recorded a third set of measurements on each infant. Twenty-two individuals were selected to be observed by an external administrator during data collection. Technical error of measurements (TEMs) were produced to assess intra-observer and inter-observer reliability. Differences between groups were tested to determine whether external observation influences reliability. RESULTS: None of the TEMs were excessively large, and coefficients of reliability ranged from 0.96 to 1.00. All intra-observer and inter-observer TEMs for the observed group were larger than those for the non-observed group. For example, the observed group's intra-observer TEMs for weight, length, abdominal circumference, and head circumference (46.18 g, 0.60 cm, 0.65 cm, 0.47 cm) were larger than the non-observed group's TEMS (9.14 g, 0.35 cm, 0.34 cm, 0.19 cm). TEMs for weight, abdominal circumference, and head circumference were significantly larger for the observed group, compared to the non-observed group (p<0.001). Inter-observer TEMs for length were also significantly larger for the observed group (p=0.031), whilst intra-observer TEMs for length were not significantly different between the two groups (p=0.137). CONCLUSIONS: Following training in anthropometry health workers in Bradford can, in general, reliably measure child growth. TEMs were comparable to data from other research studies and all coefficients of reliability were indicative of good quality control. Reliability measurement provides a method of quality assurance for routine data monitoring. If commissioners of health services are to be informed by these data then some form of reliability assessment should be considered, and if employed external observation is recommended to improve validity.

Effects of variation at the ALDH2 locus on alcohol metabolism, sensitivity, consumption, and dependence in Europeans.

BACKGROUND: The low-activity variant of the aldehyde dehydrogenase 2 (ALDH2) gene found in East Asian populations leads to the alcohol flush reaction and reduces alcohol consumption and risk of alcohol dependence (AD). We have tested whether other polymorphisms in the ALDH2 gene have similar effects in people of European ancestry. METHODS: Serial measurements of blood and breath alcohol, subjective intoxication, body sway, skin temperature, blood pressure, and pulse were obtained in 412 twins who took part in an alcohol challenge study. Participants provided data on alcohol reactions, alcohol consumption, and symptoms related to AD at the time of the study and subsequently. Haplotypes based on 5 single-nucleotide polymorphisms (SNPs) were used in tests of the effects of variation in the ALDH2 gene on alcohol metabolism and alcohol's effects. RESULTS: The typed SNPs were in strong linkage disequilibrium and 2 complementary haplotypes comprised 83% of those observed. Significant effects of ALDH2 haplotype were observed for breath alcohol concentration, with similar but smaller and nonsignificant effects on blood alcohol. Haplotype-related variation in responses to alcohol, and reported alcohol consumption, was small and not consistently in the direction predicted by the effects on alcohol concentrations. CONCLUSIONS: Genetic variation in ALDH2 affects alcohol metabolism in Europeans. However, the data do not support the hypothesis that this leads to effects on alcohol sensitivity, consumption, or risk of dependence.