2,195 research outputs found
MECHANICAL DAMPING SYSTEM FOR STRUCTURES
A mechanical damping system for a structure is provided. The mechanical damping system comprises a tubular impact frame secured to the structure. A support frame is secured to the structure with the support frame spaced from the impact frame. An elongated member is provided having a first end and a second end. The first end is secured within the support frame and the second end is free from connection and extends into the impact frame. At least one impact mass is secured to the second end of the elongated member, the impact mass movable within and contactable with the impact frame
Further characterization of glycine-containing microcystins from the McMurdo Dry Valleys of Antarctica
Microcystins are hepatotoxic cyclic peptides produced by several cyanobacterial genera worldwide. In 2008, our research group identified eight new glycine-containing microcystin congeners in two hydro-terrestrial mat samples from the McMurdo Dry Valleys of Eastern Antarctica. During the present study, high-resolution mass spectrometry, amino acid analysis and micro-scale thiol derivatization were used to further elucidate their structures. The Antarctic microcystin congeners contained the rare substitution of the position-1 D-alanine for glycine, as well as the acetyl desmethyl modification of the position-5 Adda moiety (3S-amino-9S-methoxy-2S,6,8S-trimethyl-10-phenyldeca-4E,6E-dienoic acid). Amino acid analysis was used to determine the stereochemistry of several of the amino acids and conclusively demonstrated the presence of glycine in the microcystins. A recently developed thiol derivatization technique showed that each microcystin contained dehydrobutyrine in position-7 instead of the commonly observed N-methyl dehydroalanine
Leukemia and Lymphoma Society
The mission of The Leukemia & Lymphoma Society (LLS) is to âcure leukemia, lymphoma, Hodgkinâs disease and myeloma, and improve the quality of life of patients and their families.â As a not-for-profit organization, LLS is structured differently from most for-profit companies. Itâs unique structure allows it to focus on its mission, but also puts the organization in direct competition with other charitable fundraising organizations, and especially the American Cancer Society and Susan B. Komen for the Cure. Economic problems have made fundraising more difficult for all companies in the industry. LLS is also in the position of partnering with big pharmaceutical companies as a deliberate part of its strategy
Efficacy of single pass UVC air treatment for the inactivation of coronavirus, MS2 coliphage and Staphylococcus aureus bioaerosols
Publication history: Accepted - 20 April 2022; Published online - 26 April 2022There is strong evidence that SARS-CoV-2 is spread predominantly by airborne transmission, with high viral loads released into the air as respiratory droplets and aerosols from the infected subject. The spread and persistence of SARS-CoV-2 in diverse indoor environments reinforces the urgent need to supplement distancing and PPE based approaches with effective engineering measures for microbial decontamination â thereby addressing the significant risk posed by aerosols. We hypothesized that a portable, single-pass UVC air treatment device (air flow 1254 L/min) could effectively inactivate bioaerosols containing bacterial and viral indicator organisms, and coronavirus without reliance on filtration technology, at reasonable scale. Robust experiments demonstrated UVC dose dependent inactivation of Staphylococcus aureus (UV rate constant (k) = 0.098 m2/J) and bacteriophage MS2, with up to 6-log MS2 reduction achieved in a single pass through the system (k = 0.119 m2/J). The inclusion of a PTFE diffuse reflector increased the effective UVC dose by up to 34% in comparison to a standard Al foil reflector (with identical lamp output), resulting in significant additional pathogen inactivation (1-log S. aureus and MS2, p < 0.001). Complete inactivation of bovine coronavirus bioaerosols was demonstrated through tissue culture infectivity (2.4-log reduction) and RT-qPCR analysis â confirming single pass UVC treatment to effectively deactivate coronavirus to the limit of detection of the culture-based method. Scenario-based modelling was used to investigate the reduction in risk of airborne person-to-person transmission based upon a single infected subject within the small room. Use of the system providing 5 air changes per hour was shown to significantly reduce airborne viral load and maintain low numbers of RNA copies when the infected subject remained in the room, reducing the risk of airborne pathogen transmission to other room users. We conclude that the application of single-pass UVC systems (without reliance on HEPA filtration) could play a critical role in reducing the risk of airborne pathogen transfer, including SARS-CoV2, in locations where adequate fresh air ventilation cannot be implemented.This research was partly funded through the Invest Northern Ireland Innovation Voucher Programme (IV130218200 and IV130232906). We are grateful to the Global Challenges Research Fund (GCRF) UK Research and Innovation (SAFEWATER; EPSRC Grant Reference EP/P032427/1) for supporting Mr Arsalan Afkhami, Dr William J Snelling and Dr Jeremy W.J. Hamilton. Research at AFBI is funded by US-Ireland Research and Development Partnership in Agriculture grants BRDC-Seq and BRDC-URTMVP. We wish to thank Jonathan McMaw at AFBI for acquisition of images
Evaluation of the patient acceptable symptom state following hip arthroscopy using the 12 item international hip outcome tool
BackgroundThe International Hip Outcome Tool 12 (iHOT-12) is a shorter version of the iHOT-33 which measures health related quality of life following treatment of hip disorders in young, active patients. The purpose of this study was identify a PASS threshold for a UK population undergoing hip arthroscopy for intra-articular hip pathology.MethodsData was identified retrospectively from a prospective database of patients undergoing hip arthroscopy under the care of a single surgeon within the date range January 2013 to March 2017. All patients with a diagnosis of femoroacetabular impingment (FAI) undergoing arthroscopic treatment were included. iHOT-12, EuroQol 5D-5âL (EQ-5D-5âL) and a satisfaction questionnaire were available pre and post-operatively. PASS was calculated using an anchor-based approach and receiver operator characteristic (ROC) analysis.Results171 patients underwent hip arthroscopy in the study period. Linked longitudinal follow-up data was available for 122 patients (71.3%) at a median of 24.3âmonths (740âdays, interquartile range 576â1047). The PASS threshold for the iHOT-12 was 59.5 (sensitivity 81.1%, specificity 83.9%; area under the curve (AUC) 0.92, 95% CI 0.87â0.97). 64% of patients achieved this score. The median postoperative iHOT-12 score was 72.5 (IQR 44) and the mean change in score was 35 (SD 25, p
Use of Biologics as an Adjunct Therapy to Arthroscopic Surgery for the Treatment of Femoroacetabular Impingement: A Systematic Review
Background:There has been a recent increase in the use of biologics in hip arthroscopy to assist in the management of femoroacetabular impingement (FAI).Purpose:To analyze the current use of biologics for the treatment of FAI and its associated lesions.Study Design:Systematic review; Level of evidence, 4.Methods:A search of the PubMed, Medline, and EMBASE databases was performed in March 2019 with use of the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The criterion for inclusion was observational, published research articles studying the therapeutic use of biologics as an adjuvant therapy during arthroscopic surgery for FAI; treatments included bone marrow aspirate concentrate, mesenchymal stem cells (MSCs), platelet-rich plasma (PRP), hyaluronic acid, growth factors, and autologous chondrocyte implantation (ACI) or autologous matrix-induced chondrogenesis (AMIC).Results:There were 9 studies that met the inclusion criteria, and a total of 674 patients were included across all studies. FAI was studied in all articles. Further, 7 studies (78%) also analyzed chondral injuries, and 3 studies also analyzed labral tears (33%). ACI or AMIC was used in 56% of studies and showed superior functional outcomes at short- and midterm follow-up versus debridement or microfracture. PRP did not improve the outcome of labral repairs at short-term follow-up.Conclusion:The current literature regarding biologic adjuncts in hip arthroscopy is varied in quality, with only one level 1 study. The use of ACI/AMIC for medium-sized chondral lesions showed promising results in individual studies; however, these were of lower quality. To enable comparisons among future studies, investigators must ensure accuracy in the reporting of biologic preparations and formulations used and homogeneity in the type and severity of lesion treated
Pre-service science teachersâ epistemological beliefs and teaching reforms in Tanzania
In an effort to understand why recent initiatives to promote learner-centred pedagogy in science teaching made a little change in the actual teaching practices of science teachers, this study explored pre-service science teachersâ beliefs about science knowledge and their teaching practices. Six pre-service science teachers were interviewed to explore their beliefs. Moreover, lessons taught by pre-service teachers were observed to see how their beliefs manifest in their teaching practices. This was followed by post-observation interviews focusing on critical incidences observed. Findings showed that pre-service science teachers hold dualist views about science. They viewed science knowledge to be simple, rigid and derivative of specific bodies of knowledge handed down by authorities such as textbooks and experts. Consistent with their beliefs, pre-service teachers asked factual questions and sought pre-determined textbook-based answers from students. They adopted transmissive teaching strategies to propagate textbook-based science knowledge. It was concluded that the way science teachers uptake the aspired learner-centred teaching may be partly due to incompatible beliefs they hold
The forgotten joint score-12 is a valid and responsive outcome tool for measuring success following hip arthroscopy for femoroacetabular impingement syndrome
PurposeThe forgotten joint score-12 (FJS-12) is an outcome questionnaire designed to evaluate joint awareness. The responsiveness and validity of the English language version of the FJS-12 in patients undergoing hip arthroscopy for femoroacetabular impingement (FAI) is not known.MethodsConsecutive patients undergoing hip arthroscopy for a diagnosis of FAI were prospectively followed up over a 1 year period. Patients completed preoperative and postoperative FJS-12, EuroQol 5 Dimension (EQ-5D-5L), and the 12-item international hip outcome tool (iHOT-12). We evaluated construct validity with Spearman correlation coefficients for the FJS-12, and responsiveness by way of effect size and ceiling effects.ResultsForty-six patients underwent hip arthroscopy, of which 42 (91%) completed post-operative PROMs at 1 year follow-up. Construct validity was strong with the iHOT-12 (r?=?0.87) and also the EQ-5D-5L (r?=?0.83). The median postoperative FJS score was 50.2 (IQR 64). The mean change in score for the FJS-12 was 31 points (SD 31) (p
Baryon Acoustic Oscillations in the Ly{\alpha} forest of BOSS DR11 quasars
We report a detection of the baryon acoustic oscillation (BAO) feature in the
flux-correlation function of the Ly{\alpha} forest of high-redshift quasars
with a statistical significance of five standard deviations. The study uses
137,562 quasars in the redshift range from the Data Release
11 (DR11) of the Baryon Oscillation Spectroscopic Survey (BOSS) of SDSS-III.
This sample contains three times the number of quasars used in previous
studies. The measured position of the BAO peak determines the angular distance,
and expansion rate, , both on a scale set by the sound
horizon at the drag epoch, . We find
and
where . The optimal
combination, is determined with a precision of
. For the value , consistent with the CMB power
spectrum measured by Planck, we find
and . Tests with mock
catalogs and variations of our analysis procedure have revealed no systematic
uncertainties comparable to our statistical errors. Our results agree with the
previously reported BAO measurement at the same redshift using the
quasar-Ly{\alpha} forest cross-correlation. The auto-correlation and
cross-correlation approaches are complementary because of the quite different
impact of redshift-space distortion on the two measurements. The combined
constraints from the two correlation functions imply values of and
that are, respectively, 7% low and 7% high compared to the
predictions of a flat CDM cosmological model with the best-fit Planck
parameters. With our estimated statistical errors, the significance of this
discrepancy is .Comment: Accepted for publication in A&A. 17 pages, 18 figure
The UV-Optical Color Dependence of Galaxy Clustering in the Local Universe
We measure the UV-optical color dependence of galaxy clustering in the local
universe. Using the clean separation of the red and blue sequences made
possible by the NUV - r color-magnitude diagram, we segregate the galaxies into
red, blue and intermediate "green" classes. We explore the clustering as a
function of this segregation by removing the dependence on luminosity and by
excluding edge-on galaxies as a means of a non-model dependent veto of highly
extincted galaxies. We find that \xi (r_p, \pi) for both red and green galaxies
shows strong redshift space distortion on small scales -- the "finger-of-God"
effect, with green galaxies having a lower amplitude than is seen for the red
sequence, and the blue sequence showing almost no distortion. On large scales,
\xi (r_p, \pi) for all three samples show the effect of large-scale streaming
from coherent infall. On scales 1 Mpc/h < r_p < 10 Mpc/h, the projected
auto-correlation function w_p(r_p) for red and green galaxies fits a power-law
with slope \gamma ~ 1.93 and amplitude r_0 ~ 7.5 and 5.3, compared with \gamma
~ 1.75 and r_0 ~ 3.9 Mpc/h for blue sequence galaxies. Compared to the
clustering of a fiducial L* galaxy, the red, green, and blue have a relative
bias of 1.5, 1.1, and 0.9 respectively. The w_p(r_p) for blue galaxies display
an increase in convexity at ~ 1 Mpc/h, with an excess of large scale
clustering. Our results suggest that the majority of blue galaxies are likely
central galaxies in less massive halos, while red and green galaxies have
larger satellite fractions, and preferentially reside in virialized structures.
If blue sequence galaxies migrate to the red sequence via processes like
mergers or quenching that take them through the green valley, such a
transformation may be accompanied by a change in environment in addition to any
change in luminosity and color.Comment: accepted by MNRA
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