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The potential benefits of a semi-active magnetorheological (MR) damper in reducing the incidence and severity of end-stop impacts of a low natural frequency suspension seat are investigated. The MR damper considered is a commercially developed product, referred to as “Motion Master semi-active damping system” and manufactured by Lord Corporation. The end-stop impact and vibration attenuation performance of a seat equipped with such a damper are evaluated and compared with those of the same seat incorporating a conventional damper. The evaluation is performed on a servo-hydraulic vibration exciter by subjecting the seat-damper combinations to a transient excitation with dominant frequency close to that of the seat and continuous random excitation class EM1 applicable to earth-moving machinery, and a more severe excitation realized by amplifying the EM1 excitation by 150%. Tests are performed for medium and firm settings of the MR damper and for seat height positions corresponding to mid-ride and ±2·54 and ±5·08 cm relative to mid-ride. The results indicate that significantly higher levels of transient excitation are necessary to induce end-stop impacts for the seat equipped with the MR damper, particularly when set for firm damping, the difference with the conventional damper being more pronounced for seat positions closer to the end-stops. Under the EM1 excitation, the results indicate that under conditions which would otherwise favour the occurrence of end-stop impacts for a seat equipped with a conventional damper, the use of the MR damper can result in considerably less severe impacts and correspondingly lower vibration exposure levels, particularly when positioned closer to its compression or rebound limit stop. [Copyright &y& Elsevier]

Purpose: This study aims to investigate the feasibility of using a commercially available clinical 0.55 T MRI scanner for comprehensive structural and functional fetal cardiac imaging., Methods: Balanced steady-state free precession (bSSFP) and phase contrast (PC) sequences were optimized by in utero studies consisting of 14 subjects for bSSFP optimization and 9 subjects for PC optimization. The signal-to-noise ratio (SNR) of the optimized sequences were investigated. Flow measurements were performed in three vessels, umbilical vein (UV), descending aorta (DAo), and superior vena cava (SVC) using the PC sequences and retrospective gating. The optimized bSSFP, PC and half-Fourier single shot turbo spin-echo (HASTE) sequences were acquired in a cohort of 21 late gestation-age fetuses (>36 weeks) to demonstrate the feasibility of a fetal cardiac exam at 0.55 T. The HASTE stacks were reconstructed to create an isotropic reconstruction of the fetal thorax, followed by automatic great vessel segmentations. The intra-abdominal UV blood flow measurements acquired with MRI were compared to ultrasound UV free-loop flow measurements., Results: Using the parameters from 1.5 T as a starting point, the bSSFP sequences were optimized at 0.55 T, resulting in a 1.6-fold SNR increase and improved image contrast compared to starting parameters, as well as good visibility of most cardiac structures as rated by two experienced fetal cardiologists. The PC sequence resulted in increased SNR and reduced scan time, subsequent retrospective gating enabled successful blood flow measurements. The reconstructions and automatic great vessel segmentations showed good quality, with 18/21 segmentations requiring no or minor refinements. Blood flow measurements were within the expected range. A comparison of the UV measurements performed with ultrasound and MRI showed agreement between the two sets of measurements, with better correlation observed at lower flows., Conclusion: We demonstrated the feasibility of low-field (0.55 T) MRI for fetal cardiac imaging. The reduced SNR at low field strength can be effectively compensated for by strategically optimizing sequence parameters. Major fetal cardiac structures and vessels were consistently visualized, and flow measurements were successfully obtained. The late gestation study demonstrated the robustness and reproducibility at low field strength. MRI performed at 0.55 T is a viable option for fetal cardiac examination., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2024 Zhang, Cleri, Woodgate, Ramirez Gilliland, Bansal, Aviles Verdera, Uus, Kyriakopoulou, St Clair, Story, Hall, Pushparajah, Hajnal, Lloyd, Rutherford, Hutter and Payette.)

Purpose: Widening the availability of fetal MRI with fully automatic real-time planning of radiological brain planes on 0.55T MRI., Methods: Deep learning-based detection of key brain landmarks on a whole-uterus echo planar imaging scan enables the subsequent fully automatic planning of the radiological single-shot Turbo Spin Echo acquisitions. The landmark detection pipeline was trained on over 120 datasets from varying field strength, echo times, and resolutions and quantitatively evaluated. The entire automatic planning solution was tested prospectively in nine fetal subjects between 20 and 37 weeks. A comprehensive evaluation of all steps, the distance between manual and automatic landmarks, the planning quality, and the resulting image quality was conducted., Results: Prospective automatic planning was performed in real-time without latency in all subjects. The landmark detection accuracy was 4.2 ± $$ \pm $$ 2.6 mm for the fetal eyes and 6.5 ± $$ \pm $$ 3.2 for the cerebellum, planning quality was 2.4/3 (compared to 2.6/3 for manual planning) and diagnostic image quality was 2.2 compared to 2.1 for manual planning., Conclusions: Real-time automatic planning of all three key fetal brain planes was successfully achieved and will pave the way toward simplifying the acquisition of fetal MRI thereby widening the availability of this modality in nonspecialist centers., (© 2024 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals LLC on behalf of International Society for Magnetic Resonance in Medicine.)

Abundance surveys are commonly used to estimate plant or animal densities and frequently require estimating detection probabilities to account for imperfect detection. The estimation of detection probabilities requires additional measurements that take time, potentially reducing the efficiency of the survey when applied to high-density populations. We conducted quadrat, removal, and distance surveys of zebra mussels ( Dreissena polymorpha ) in three central Minnesota lakes and determined how much survey effort would be required to achieve a pre-specified level of precision for each abundance estimator, allowing us to directly compare survey design efficiencies across a range of conditions. We found that the required sampling effort needed to achieve our precision goal depended on both the survey design and population density. At low densities, survey designs that could cover large areas but with lower detection probabilities, such as distance surveys, were more efficient ( i.e ., required less sampling effort to achieve the same level of precision). However, at high densities, quadrat surveys, which tend to cover less area but with high detection rates, were more efficient. These results demonstrate that the best survey design is likely to be context-specific, requiring some prior knowledge of the underlying population density and the cost/time needed to collect additional information for estimating detection probabilities., Competing Interests: The authors declare that they have no competing interests., (© 2023 Ferguson et al.)

In this randomized clinical trial, we examined whether the effect of true acupuncture can be differentiated from sham acupuncture (pain and functionality) by analyzing quantitative sensory testing (QST) profiles in chronic pain participants. We recruited 254 healthy or chronic back and neck pain participants. Healthy subjects were included to control for a possible effect of acupuncture on baseline QST changes. Study participants received 6 sessions (twice weekly) of true acupuncture, sham acupuncture, or no acupuncture treatment (routine care). Quantitative sensory testing profiles, pain scores, and functionality profile were obtained at baseline (visit 1) and after 3 (visit 4) or 6 sessions (visit 7). A total of 204 participants were analyzed. We found no QST profile changes among 3 groups (P = 0.533 and P = 0.549, likelihood ratio tests) in either healthy or chronic pain participants. In chronic back and neck pain participants, true acupuncture reduced pain (visit 4: difference in mean [DIM] = -0.8, 95% confidence interval [CI]: -1.4 to -0.1, adjusted P = 0.168; visit 7: DIM = -1.0, 95% CI: -1.7 to -0.3, adjusted P = 0.021) and improved functional status including physical functioning (DIM = 14.21, 95% CI: 5.84-22.58, adjusted P = 0.003) and energy/fatigue (DIM = 12.28, 95% CI: 3.46-21.11, adjusted P = 0.021) as compared to routine care. Our results indicate that QST was not helpful to differentiate between true acupuncture and sham acupuncture (primary outcome) in this study, although true acupuncture reduced pain and improved functionality (secondary outcomes) when compared with routine care.

Logistic regression models-or "sightability models"-fit to detection/non-detection data from marked individuals are often used to adjust for visibility bias in later detection-only surveys, with population abundance estimated using a modified Horvitz-Thompson (mHT) estimator. More recently, a model-based alternative for analyzing combined detection/non-detection and detection-only data was developed. This approach seemed promising, since it resulted in similar estimates as the mHT when applied to data from moose (Alces alces) surveys in Minnesota. More importantly, it provided a framework for developing flexible models for analyzing multiyear detection-only survey data in combination with detection/non-detection data. During initial attempts to extend the model-based approach to multiple years of detection-only data, we found that estimates of detection probabilities and population abundance were sensitive to the amount of detection-only data included in the combined (detection/non-detection and detection-only) analysis. Subsequently, we developed a robust hierarchical modeling approach where sightability model parameters are informed only by the detection/non-detection data, and we used this approach to fit a fixed-effects model (FE model) with year-specific parameters and a temporally-smoothed model (TS model) that shares information across years via random effects and a temporal spline. The abundance estimates from the TS model were more precise, with decreased interannual variability relative to the FE model and mHT abundance estimates, illustrating the potential benefits from model-based approaches that allow information to be shared across years.

Background: To develop content validity of a comprehensive patient-reported outcome (PRO) measure following current best scientific methodology to standardize assessment of influenza (flu) symptoms in clinical research., Methods: Stage I (Concept Elicitation): 1:1 telephone interviews with influenza-positive adults (≥18 years) in the US and Mexico within 7 days of diagnosis. Participants described symptom type, character, severity, and duration. Content analysis identified themes and developed the draft Flu-PRO instrument. Stage II (Cognitive Interviewing): The Flu-PRO was administered to a unique set of influenza-positive adults within 14 days of diagnosis; telephone interviews addressed completeness, respondent interpretation of items and ease of use., Results: Samples: Stage I: N = 46 adults (16 US, 30 Mexico); mean (SD) age: 38 (19), 39 (14) years; % female: 56%, 73%; race: 69% White, 97% Mestizo. Stage II: N = 34 adults (12 US, 22 Mexico); age: 37 (14), 39 (11) years; % female: 50%, 50%; race: 58% White, 100% Mestizo., Symptoms: Symptoms identified by >50%: coughing, weak or tired, throat symptoms, congestion, headache, weakness, sweating, chills, general discomfort, runny nose, chest (trouble breathing), difficulty sleeping, and body aches or pains. No new content was uncovered during Stage II; participants easily understood the instrument., Conclusions: Results show the 37-item Flu-PRO is a content valid measure of influenza symptoms in adults with a confirmed diagnosis of influenza. Research is underway to evaluate the suitability of the instrument for children and adolescents. This work can form the basis for future quantitative tests of reliability, validity, and responsiveness to evaluate the measurement properties of Flu-PRO for use in clinical trials and epidemiology studies.

Background: Colistin resistance is of concern since it is increasingly needed to treat infections caused by bacteria resistant to all other antibiotics and has been associated with poorer outcomes. Longitudinal data from in vivo series are sparse., Methods: Under a quality-improvement directive to intensify infection-control measures, extremely drug-resistant (XDR) bacteria undergo phenotypic and molecular analysis., Results: Twenty-eight XDR Acinetobacter baumannii isolates were longitudinally recovered during colistin therapy. Fourteen were susceptible to colistin, and 14 were resistant to colistin. Acquisition of colistin resistance did not alter resistance to other antibiotics. Isolates had low minimum inhibitory concentrations of an investigational aminoglycoside, belonged to multi-locus sequence type 94, were indistinguishable by pulsed-field gel electrophoresis and optical mapping, and harbored a novel pmrC1A1B allele. Colistin resistance was associated with point mutations in the pmrA1 and/or pmrB genes. Additional pmrC homologs, designated eptA-1 and eptA-2, were at distant locations from the operon. Compared with colistin-susceptible isolates, colistin-resistant isolates displayed significantly enhanced expression of pmrC1A1B, eptA-1, and eptA-2; lower growth rates; and lowered fitness. Phylogenetic analysis suggested that colistin resistance emerged from a single progenitor colistin-susceptible isolate., Conclusions: We provide insights into the in vivo evolution of colistin resistance in a series of XDR A. baumannii isolates recovered during therapy of infections and emphasize the importance of antibiotic stewardship and surveillance.

Link-tracing sampling designs can be used to study human populations that contain "hidden" groups who tend to be linked together by a common social trait. These links can be used to increase the sampling intensity of a hidden domain by tracing links from individuals selected in an initial wave of sampling to additional domain members. Chow and Thompson (2003, Survey Methodology 29, 197-205) derived a Bayesian model to estimate the size or proportion of individuals in the hidden population for certain link-tracing designs. We propose an addition to their model that will allow for the modeling of a quantitative response. We assess properties of our model using a constructed population and a real population of at-risk individuals, both of which contain two domains of hidden and nonhidden individuals. Our results show that our model can produce good point and interval estimates of the population mean and domain means when our population assumptions are satisfied., (© 2011, The International Biometric Society.)

Background: During the 2010-2011 influenza season, a small sub-group of 2009 influenza A(H1N1) viruses (hereafter referred to as 2009 A(H1N1)) emerged that was associated with more severe clinical outcomes in Ecuador and North America. Genetically, the haemagglutinin (HA) of this sub-clade was distinct from HAs found in viruses associated with severe outbreaks in 2010 from the United Kingdom and from other global specimens isolated earlier in the season., Objective: We report the emergence of a novel 2009 A(H1N1) variant possessing a re-emergent HA D222N mutation obtained from patients with severe respiratory illnesses and phylogenetically characterise these D222N mutants with other severe disease-causing variants clustering within a common emerging sub-clade., Case Reports: In early 2011, three cases of 2009 A(H1N1) infection, two from Quito, Ecuador, and one from Washington, DC, USA, were complicated by severe pneumonia requiring mechanical ventilation, resulting in one fatality. These cases were selected due to the reported nature of the acute respiratory distress (ARD) that were captured in Department of Defence (DoD)-sponsored global influenza surveillance nets., Results: Genetically, the 2009 A(H1N1) strains isolated from two of the three severe cases carried a prominent amino acid change at position 222 (D222N) within the primary HA receptor binding site. Furthermore, these cases represent an emerging sub-clade of viruses defined by amino acid changes within HA: N31D, S162N, A186T and V272I. Phylogenetically, these viruses share a high degree of homology with strains associated with recent fatal cases in Chihuahua, Mexico., Discussion: Previously, enhanced virulence associated with the change, D222G, has been clinically linked to severe morbidity and mortality. Initial observations of the prevalence of a novel sub-clade of strains in the Americas suggest that viruses with a re-emergent D222N mutation may too correlate with severe clinical manifestations. These findings warrant heightened vigilance for emerging sub-clades of 2009 A(H1N1) and presumptive clinical implications., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Before treating onychomycosis, it is important to exclude other conditions such as lichen planus and psoriasis. The purpose of this study was to evaluate physician preferences and uses of diagnostic tests for toenail onychomycosis (TO) by surveying dermatologists (D), podiatrists (P) and family practitioners (FP) in the United States. Surveys were mailed to approximately 1000 randomly sampled physicians from each of the three specialities. The questionnaire consisted of 15 items regarding physician and practice characteristics, number of patients with TO seen and treated, tests used to diagnose TO and reasons for using the tests. Results were analysed using several statistical methods. Response rates were low (D33.7%; P16.6%; FP28.4%). Ds and Ps (75.2%) and FPs (43.4%) reported feeling 'very confident' at diagnosing onychomycosis. KOH was the preferred diagnostic test for all three specialities. More Ds (75.4%) felt 'very confident' interpreting potassium hydroxide (KOH) exams than Ps (24.9%) and FPs (18.5%). Use of KOH exams was statistically associated with confidence interpreting exams (P P = 0.04092; D & FP P < 0.0001). Some FPs (46.6%) and Ps (21.6%) did not obtain a confirmatory diagnostic test prior to the treatment of onychomycosis while 63.6% of Ds 'almost always/always' did. While limited by low-response rate, this study provides pilot information on the diagnostic preferences for TO by American D, P and FP.

Staff nurses have a key role in ensuring that practice is evidenced-based. This article discusses the application of a model for evidence-based practice change by staff nurses in an acute care setting who examined the practice of using sterile gloves for postoperative wound dressing changes. This initiative was in response to the challenge that it was unnecessary to use sterile instead of nonsterile gloves. Extensive literature search revealed insufficient evidence to justify a practice change to nonsterile gloves.

For the cardiac transplant recipients in this study, spirituality was like a beacon of light, providing illumination and sustaining hope while enduring illness. Spirituality was nurtured by Developing Faith and by the Presence of significant others, health care providers, and the Divine to sustain hope. Spirituality throughout the transplantation process was described by concepts of faith, presence, enduring illness, and sustaining hope. The four dynamic phases of Enduring Illness can assist health care providers in understanding what spirituality means to transplant patients. This conceptual model of spirituality demonstrates the important role that spirituality plays in recovery. Clinical application of this model will allow health care providers involved in the care of cardiac transplant patients to integrate spirituality into their patients' plan of care. With future research, this model can be easily modified and built upon to meet the needs of cardiac transplant patients in all phases of transplantation.

A historical review of neonatal assessment procedures is presented to demonstrate the trends in advancement of the field and attempts toward collaboration of medicine and psychology in contributions to the area. The literature suggests that the medically oriented neurological examinations have continued to be altered and improved. The growth of behaviorism within psychology and the view that behavior is closely related to underlying neurological mechanisms have contributed to the development of behaviorally oriented assessment procedures. These trends have combined successfully in the development of the Brazelton Neonatal Assessment Scale, which focuses on assessment of behavioral capabilities reflecting the quality of parent-infant relationships. The most recent contributions are directed toward development of specialized assessment techniques to fulfill specific research needs. Suggestions and cautions for use of available procedures are presented.