200 research outputs found

    Safety and Driver Behavior Studies at Multiple Lane Approaches to Stop-Controlled Intersections

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    Multiple-lane approaches (MLAs) controlled by stop signs are becoming increasingly common in Nebraska. Installation of MLAs occurs when a single approach lane can no longer adequately serve the minor road traffic volume, and a signal is unwarranted because Manual of Uniform Traffic Control Devices (MUTCD) warrants are not satisfied (7, FHWA, 2003). A common example of a location at which MLA stop-controlled intersections can occur in Nebraska is the rural intersection of two state or federal highways. Forty such intersections in Nebraska were available for study in this research. Additionally, such intersections are often located in suburban areas of Nebraska municipalities where the local-collector network of a residential development connects to an arterial roadway. The objective of this research was to investigate driver safety and behavior at two-way stop-controlled MLA intersections. The reason for the investigation is to gain a better understanding of potential sight distance limitations due to side-by-side stopped vehicles at stop signs, as described earlier. Below is a summary of recommendations based upon safety study aspects of the project: Results of the before-after comparison group safety studies concerning crash frequency indicated that signalization of MLA-type intersections results in improved safety, however no statistically significant difference was found at the 95 percent confidence level. Results of the before-after comparison group safety study of the conversion of one MLA-type intersection to an SLA configuration showed that the crash frequency was reduced when the approach was changed to a single lane. However, the study of average crash rates indicated that the MLA-type intersection had a statistically significant lower average than the SLA intersection at the 95 percent level of confidence. Also, the reduction of the number of approach lanes from two to one can increase driver delay and user costs. Comparison of 3-year average crash rates at MLA intersections with 2-lane major roads with similar statewide intersection averages indicates that they have a higher than average rate when the roadway design necessitates a horizontal curve along the major road or minor road horizontal alignment in the near proximity of the point of intersection. Comparison of 3-year average crash rates at MLA intersections with 4-lane major roads with similar statewide intersection averages indicates that they have a higher than average rate when in urban areas. Therefore, use of this type of intersection along 4-lane urban roadways should be limited. If MLA-type intersections are determined to be the intersection type of choice: Provide consistent and redundant positive visual guidance to promote the positioning of right-turning drivers in advance of leftturning drivers at MLA-type intersections. Each visual cue issue, recommendation for improvement, explanation of recommendation and official guideline resource is summarized following FIGURES 38 and 39 in TABLE 24. FIGURE 40 shows a plan view of the proposed recommendations. Develop a combined text and iconic STOP AT LINE sign. Several designs should be tested with a pool of Nebraska drivers to determine the most easily interpreted design. Positioning of the sign should follow the guidelines in FIGURE 39 and TABLE 24. Provide better driver information about the new proposed sign and the appropriate stop position at a stop bar location in the Nebraska Driver’s Manual. Additional information should be provided on page 40 of the current Nebraska Driver’s Manual to better inform drivers about the desired stopping position at a painted stop bar on the pavement of a driving lane. Update an MLA-type intersection using the proposals defined in the research report and conduct a before-after field study. To better understand if the proposed recommendations result in a significant improvement in driver behavior, it is highly recommended that a field study be performed to quantify the improvement, if any

    The Anti-Sigma Factor MucA of Pseudomonas aeruginosa: Dramatic Differences of a mucA22 vs. a ΔmucA Mutant in Anaerobic Acidified Nitrite Sensitivity of Planktonic and Biofilm Bacteria in vitro and During Chronic Murine Lung Infection

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    Mucoid mucA22 Pseudomonas aeruginosa (PA) is an opportunistic lung pathogen of cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) patients that is highly sensitive to acidified nitrite (A-NO2-). In this study, we first screened PA mutant strains for sensitivity or resistance to 20 mM A-NO2- under anaerobic conditions that represent the chronic stages of the aforementioned diseases. Mutants found to be sensitive to A-NO2- included PA0964 (pmpR, PQS biosynthesis), PA4455 (probable ABC transporter permease), katA (major catalase, KatA) and rhlR (quorum sensing regulator). In contrast, mutants lacking PA0450 (a putative phosphate transporter) and PA1505 (moaA2) were A-NO2- resistant. However, we were puzzled when we discovered that mucA22 mutant bacteria, a frequently isolated mucA allele in CF and to a lesser extent COPD, were more sensitive to A-NO2- than a truncated ΔmucA deletion (Δ157–194) mutant in planktonic and biofilm culture, as well as during a chronic murine lung infection. Subsequent transcriptional profiling of anaerobic, A-NO2--treated bacteria revealed restoration of near wild-type transcript levels of protective NO2- and nitric oxide (NO) reductase (nirS and norCB, respectively) in the ΔmucA mutant in contrast to extremely low levels in the A-NO2--sensitive mucA22 mutant. Proteins that were S-nitrosylated by NO derived from A-NO2- reduction in the sensitive mucA22 strain were those involved in anaerobic respiration (NirQ, NirS), pyruvate fermentation (UspK), global gene regulation (Vfr), the TCA cycle (succinate dehydrogenase, SdhB) and several double mutants were even more sensitive to A-NO2-. Bioinformatic-based data point to future studies designed to elucidate potential cellular binding partners for MucA and MucA22. Given that A-NO2- is a potentially viable treatment strategy to combat PA and other infections, this study offers novel developments as to how clinicians might better treat problematic PA infections in COPD and CF airway diseases

    Additional standing balance circuit classes during inpatient rehabilitation improved balance outcomes: an assessor-blinded randomised controlled trial

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    Abstract Objective: to evaluate the impact on balance ( postural control) of six 1-h circuit classes that targeted balance in addition to usual therapy for rehabilitation inpatients. Design: a randomised controlled trial with 2-week and 3-month follow-up. Participants: one hundred and sixty-two general rehabilitation inpatients, Bankstown-Lidcombe Hospital, Australia. Intervention: intervention group participants received six 1-h circuit classes over a 2-week period in addition to usual therapy. Control group participants received usual therapy. Results: standing balance performance ( primary outcome) was better in the intervention group than in the control group at 2 weeks (between-group difference after adjusting for baseline values 3.3 s; 95% confidence interval (CI) 0.84 to 5.7, P = 0.009), but the between-group difference was not statistically significant at 3 months (3.4 s; 95% CI −0.56 to 7.38, P = 0.092). Intervention group outcomes were significantly better than the control groups for mobility performance (Short Physical Performance Battery) at 2 weeks (1.19, 95% CI 0.52 to 1.87, P <0.01) and 3 months (1.00, 95% CI 0.00 to 2.00, P < 0.049) and self-reported functioning (AM-PAC) at 2 weeks (5.39, 95% CI 1.20 to 9.57, P = 0.012). The intervention group had a 4.1-day shorter rehabilitation unit stay (95% CI −8.3 to 0.16, P = 0.059) and a lower risk of readmission in the 3 months after randomisation (incidence rate ratio 0.70, 95% CI 0.42 to 1.18, P = 0.184), but these differences were not statistically significant. Conclusion: two weeks of standing balance circuit classes in addition to usual therapy improved balance in general rehabilitation inpatients at 2 weeks

    The AllWISE Motion Survey, Part 2

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    We use the AllWISE Data Release to continue our search for WISE-detected motions. In this paper, we publish another 27,846 motion objects, bringing the total number to 48,000 when objects found during our original AllWISE motion survey are included. We use this list, along with the lists of confirmed WISE-based motion objects from the recent papers by Luhman and by Schneider et al. and candidate motion objects from the recent paper by Gagne et al. to search for widely separated, common-proper-motion systems. We identify 1,039 such candidate systems. All 48,000 objects are further analyzed using color-color and color-mag plots to provide possible characterizations prior to spectroscopic follow-up. We present spectra of 172 of these, supplemented with new spectra of 23 comparison objects from the literature, and provide classifications and physical interpretations of interesting sources. Highlights include: (1) the identification of three G/K dwarfs that can be used as standard candles to study clumpiness and grain size in nearby molecular clouds because these objects are currently moving behind the clouds, (2) the confirmation/discovery of several M, L, and T dwarfs and one white dwarf whose spectrophotometric distance estimates place them 5-20 pc from the Sun, (3) the suggestion that the Na 'D' line be used as a diagnostic tool for interpreting and classifying metal-poor late-M and L dwarfs, (4) the recognition of a triple system including a carbon dwarf and late-M subdwarf, for which model fits of the late-M subdwarf (giving [Fe/H] ~ -1.0) provide a measured metallicity for the carbon star, and (5) a possible 24-pc-distant K5 dwarf + peculiar red L5 system with an apparent physical separation of 0.1 pc.Comment: 62 pages with 80 figures, accepted for publication in The Astrophysical Journal Supplement Series, 23 Mar 2016; second version fixes a few small typos and corrects the footnotes for Table

    Diaphragmatic Injuries among Severely Injured Patients (ISS ≥ 16)—An Indicator of Injury Pattern and Severity of Abdominal Trauma

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    Background and Objectives: Abdominal trauma among severely injured patients with an injury severity score (ISS) of 16 and above can lead to potentially life-threatening injuries that might need immediate surgical intervention. Traumatic injuries to the diaphragm (TID) are a challenging condition often accompanied by other injuries in the thoracoabdominal region. Materials and Methods: We retrospectively analyzed the occurrence and clinical course of TID among severely injured patients treated at our center between 2008 and 2019 and compared them to other groups of severely injured patients without TID. Results: Thirty-five patients with TID and a median ISS of 41 were treated in the period mentioned above. They were predominantly middle-aged men and mostly victims of blunt trauma as a consequence of motor vehicle accidents. A total of 70.6% had left-sided TID, and in 69.6%, the size of defect was larger than 10 cm. The diagnosis was made with computed tomography (CT) in 68.6% of the cases, while in 25.8%, it was made intraoperatively or delayed by a false-negative initial CT scan, and in 5.7%, an intraoperative diagnosis was made without preoperative CT imaging. Surgical repair was mostly conducted via laparotomy, performing a direct closure with continuous suture. A comparison to 191 patients that required laparotomy for abdominal injuries other than TID revealed significantly higher rates of concomitant injuries to several abdominal organs among patients suffering from TID. Compared to all other severely injured patients treated in the same period (n = 1377), patients suffering from TID had a significantly higher median ISS and a longer mean duration of hospital stay. Conclusions: Our findings show that TID can be seen as an indicator of particularly severe thoracoabdominal trauma that requires increased attention from the treatment team so as not to miss relevant concomitant injuries that require immediate intervention

    From cheek swabs to consensus sequences : an A to Z protocol for high-throughput DNA sequencing of complete human mitochondrial genomes

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    Background: Next-generation DNA sequencing (NGS) technologies have made huge impacts in many fields of biological research, but especially in evolutionary biology. One area where NGS has shown potential is for high-throughput sequencing of complete mtDNA genomes (of humans and other animals). Despite the increasing use of NGS technologies and a better appreciation of their importance in answering biological questions, there remain significant obstacles to the successful implementation of NGS-based projects, especially for new users. Results: Here we present an ‘A to Z’ protocol for obtaining complete human mitochondrial (mtDNA) genomes – from DNA extraction to consensus sequence. Although designed for use on humans, this protocol could also be used to sequence small, organellar genomes from other species, and also nuclear loci. This protocol includes DNA extraction, PCR amplification, fragmentation of PCR products, barcoding of fragments, sequencing using the 454 GS FLX platform, and a complete bioinformatics pipeline (primer removal, reference-based mapping, output of coverage plots and SNP calling). Conclusions: All steps in this protocol are designed to be straightforward to implement, especially for researchers who are undertaking next-generation sequencing for the first time. The molecular steps are scalable to large numbers (hundreds) of individuals and all steps post-DNA extraction can be carried out in 96-well plate format. Also, the protocol has been assembled so that individual ‘modules’ can be swapped out to suit available resources

    ManyDogs Project: A Big Team Science Approach to Investigating Canine Behavior and Cognition

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    Dogs have a special place in human history as the first domesticated species and play important roles in many cultures around the world. However, their role in scientific studies has been relatively recent. With a few notable exceptions (e.g., Darwin, Pavlov, Scott, and Fuller), domestic dogs were not commonly the subject of rigorous scientific investigation of behavior until the late 1990s. Although the number of canine science studies has increased dramatically over the last 20 years, most research groups are limited in the inferences they can draw because of the relatively small sample sizes used, along with the exceptional diversity observed in dogs (e.g., breed, geographic location, experience). To this end, we introduce the ManyDogs Project, an international consortium of researchers interested in taking a big team science approach to understanding canine behavioral science. We begin by discussing why studying dogs provides valuable insights into behavior and cognition, evolutionary processes, human health, and applications for animal welfare. We then highlight other big team science projects that have previously been conducted in canine science and emphasize the benefits of our approach. Finally, we introduce the ManyDogs Project and our mission: (a) replicating important findings, (b) investigating moderators that need a large sample size such as breed differences, (c) reaching methodological consensus, (d) investigating cross-cultural differences, and (e) setting a standard for replication studies in general. In doing so, we hope to address previous limitations in individual lab studies and previous big team science frameworks to deepen our understanding of canine behavior and cognition
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