511 research outputs found
Letter From Frederick D. Grant to Francis Mairs Huntington-Wilson, March 20, 1897
In this copy of a typed letter from Frederick Grant to Francis Mairs Huntington-Wilson, Grant agrees to speak with Horace Porter about securing a position for Huntington Wilson as Second Secretary to the Ambassador in Paris.https://digitalcommons.ursinus.edu/fmhw_early_career/1005/thumbnail.jp
TripAdvisor Reviews of London Museums: A New Approach to Understanding Visitors
The digital revolution has affected museums in many ways, both directly and indirectly. A major external change is the rise of user-written reviews; that is, reviews written by museum visitors and posted on the Internet. User-generated reviews pose challenges to museums, as they are publicly available and largely outside the control of museums. This article discusses research on reviews of accredited museums in London. The authors’ data set consists of all reviews written about 88 museums that were posted on TripAdvisor during 2014, a total of 22,940 reviews. Using a technique called topic modelling, they describe 19 themes in reviewers’ stories of their visits. The authors find that museum visitors pay attention to the ancillary aspects of their visit: queues, cost, food service, toilets, and activities for children. They make fewer comments on the cultural side of the museum experience. However, these cultural aspects do matter and are associated with positive reviews. The authors argue that reviewers consider museums as part of a wider leisure sector. They close with a discussion of the implications of their study for museum management and assess the usefulness of user-generated content as a source of data on museum visitors
The value of SPECT in the detection of stress injury to the pars interarticularis in patients with low back pain
The medical cost associated with back pain in the United States is considerable and growing. Although the differential diagnosis of back pain is broad, epidemiological studies suggest a correlation between adult and adolescent complaints. Injury of the pars interarticularis is one of the most common identifiable causes of ongoing low back pain in adolescent athletes. It constitutes a spectrum of disease ranging from bone stress to spondylolysis and spondylolisthesis. Bone stress may be the earliest sign of disease. Repetitive bone stress causes bone remodeling and may result in spondylolysis, a non-displaced fracture of the pars interarticularis. A fracture of the pars interarticularis may ultimately become unstable leading to spondylolisthesis. Results in the literature support the use of bone scintigraphy to diagnose bone stress in patients with suspected spondylolysis. Single photon emission computed tomography (SPECT) provides more contrast than planar bone scintigraphy, increases the sensitivity and improves anatomic localization of skeletal lesions without exposing the patient to additional radiation. It also provides an opportunity for better correlation with other imaging modalities, when necessary. As such, the addition of SPECT to standard planar bone scintigraphy can result in a more accurate diagnosis and a better chance for efficient patient care. It is our expectation that by improving our ability to correctly diagnose bone stress in patients with suspected injury of the posterior elements, the long-term cost of managing this condition will be lowered
The Varga Site: A Multicomponent, Stratified Campsite in the Canyonlands of Edwards County, Texas
Data recovery excavations at the Varga Site were conducted in two phases during 2002 by archeologists from the Cultural Resources Department of TRC Environmental Corporation’s (TRC’s) Austin office under contract to Texas Department of Transportation (TxDOT) Scientific Service Contract No. 572XXSA004. This mitigation program was necessitated by the proposed reconstruction of the crossing of a Ranch to Market Road over Hackberry Creek, immediately south of the site in northeastern Edwards County. These archeological investigations were conducted as part of the responsibilities of TxDOT under existing federal and state legislation for the protection of cultural resources.
Geoarcheological trenching and hand-excavations within the existing 31 m wide road right-of-way of 7- m-wide paved Ranch to Market Road focused on the alluvial fines in the first terrace overlooking Hackberry Creek immediately adjacent to a spring. The southern edge of the terrace contains relatively fine-grained sediments ranging from 15 to 150 centimeter (cm) thick that overlie coarse stream gravels that extend to an unknown depth. The modern ground surface had been impacted by road construction and maintenance activities, as well as by light erosion.
Block Excavations were conducted on both sides of the pavement and resulted in the hand-excavations of a total of 207.75 square meters (m2), including 83 m2 (66.2 m3) in Block A on the western side and a 124.75 m2 (38.26 m3) area in Block B on the eastern side. Archeological deposits in the investigated part of the site extend to the southern lip of the first terrace and extend about 50 m to the north. The excavations yielded evidence of a multiple component campsite with three distinct and a fourth less distinct prehistoric components. In Block A, the 100 to 150 cm thick fine-grained sediments yielded four intact cultural components. Block B only targeted the youngest, Toyah component. The fine-grained alluvial sediments that comprise the first terrace contain discrete occupations radiocarbon dated to the Late Prehistoric period Toyah phase (ca. 290 to 660 B.P.), the Late Archaic period (ca. 1,700 to 2,300 B.P.), and the Early Archaic period (ca. 5,200 to 6,300 B.P.). A Middle Archaic period (ca. 3,900 to 4,800 B.P.) component was also recognized, but was not as clearly defined as were the other three components. Krotovina disturbance was relatively extensive in parts of the investigated site area. Nevertheless, the archeological deposits exhibited a high degree of contextual integrity.
The Toyah phase component contains a rich assemblage of cultural material (ca. 65,000 pieces), including lithic debitage (ca. 26,000), quantities of highly fragmented bones (ca. 18,700), small burned rocks (ca. 16,000), formal and informal stone tools (ca. 1,850), scattered ceramic sherds (ca. 100), and 11 burned rock features. This component was radiocarbon dated by 14 accepted dates to between 290 and 660 B.P. Preservation was generally good, but mixing and probable overprinting contributed to poor horizontal patterning and an inability to identify discrete activity areas.
The Late Archaic period component consists primarily of a large, nearly 6 m diameter lens of burned rock that is interpreted as an incipient burned rock midden with an indistinct central pit oven. This feature was associated with a buried A horizon and exhibited a high degree of stratigraphic integrity. However, beyond the ill-defined boundaries of this burned rock feature, limited lithic debitage assemblage (ca. 1,800), a few mussel shell fragments, five isolated burned rock features, scattered burned rocks, and occasional chipped stone tools (ca. 30) totaling less than 6,000 pieces. Identified dart point styles associated with this midden include Frio, Marcos, Ensor, Castroville, and Edgewood. This component was radiocarbon dated by 11 accepted dates to a 600-year period between 1,700 and 2,310 B.P.
The Middle Archaic component was not well-defined, but definitely present and dispersed below the Late Archaic component and above the Early Archaic component. These materials were vertically distributed over a 20 to 40 cm thick zone that lacked completely sterile levels or visible breaks in the stratigraphy between the other cultural events. Lithic debitage (ca. 4,400) dominates the recovered assemblage (ca. 6,000), with limited burned rocks (ca. 3,000), a few formal chipped stone tools (ca. 25), and moderate frequency of vertebrate remains (100 g) also present. Two poorly organized burned rock features were also identified and documented. Five Early Triangular projectile points and one Carrizo point fragment occurred within this component. Two wood charcoal assays and one radiocarbon date on a deer bone directly date this Middle Archaic component to ca. 900-radiocarbon year period between 3,910 and 4,820 B.P. These three absolute dates are stratigraphically in order compared to the radiocarbon dates from the cultural components above and below.
The Early Archaic component was defined by quantities of dense cultural debris (ca. 135,000) within a roughly 30 cm thick zone directly on top and mixed into coarse river gravels and below the Middle Archaic component. The cultural material varied in depth from a shallow 50 cm below datum (bd) at the north end to a much deeper 120 cmbd in the southern end of Block A. The recovery of a robust assemblage of dart points (170 specimens) that consisted of Group 2—Early Corner-Notched, Bandy, Martindale, Gower, and Merrell dart points indicates that this zone represents many occupations that occurred over a relatively broad time frame. The dart points were associated with a diverse tool assemblage (ca. 1,300). Organic preservation was poor in this lower stratum, but occasional fragments of animal bone, plant seeds, and wood charcoal were recovered. Fifteen organic samples of diverse materials yielded radiocarbon dates that document a minimum use period of 1,080-radiocarbon years from 5,200 B.P. to 6,280 B.P.
Greater insight and understanding of each of these four components represented was made possible through the employment of numerous technical analyses, including the radiocarbon dating of 66 samples, six optically stimulated luminescence dates, use-wear analysis and organic residue identifications on 156 stone specimens, petrographic analyses on 18 pottery and one local sediment samples, pollen and phytolith analyses on 25 paired samples, instrumental neutron activation analysis on 261 chert samples and 18 pottery sherds, fatty acid composition on eight pottery sherds and 94 burned rocks, stable carbon and nitrogen analyses on 112 samples, macrobotanical analyses on 44 float and 75 individual charcoal samples, and granulometric and compositional studies on 10 sediment samples. The combined results have contributed significantly to a greater understanding of the Varga Site as a whole and documented specific information concerning the behaviors of the people who occupied the site. These and other technical analyses are urged for other excavated sites in the future to continue to broaden our understanding of the human behaviors at specific sites and throughout the broader region. This will add to a growing database that will foster a better understanding of prehistoric lifeways across Texas
A Detailed Observational Analysis of V1324 Sco, the Most Gamma-Ray Luminous Classical Nova to Date
It has recently been discovered that some, if not all, classical novae emit
GeV gamma rays during outburst, but the mechanisms involved in the production
of the gamma rays are still not well understood. We present here a
comprehensive multi-wavelength dataset---from radio to X-rays---for the most
gamma-ray luminous classical nova to-date, V1324 Sco. Using this dataset, we
show that V1324 Sco is a canonical dusty Fe-II type nova, with a maximum ejecta
velocity of 2600 km s and an ejecta mass of few
M. There is also evidence for complex shock interactions, including a
double-peaked radio light curve which shows high brightness temperatures at
early times. To explore why V1324~Sco was so gamma-ray luminous, we present a
model of the nova ejecta featuring strong internal shocks, and find that higher
gamma-ray luminosities result from higher ejecta velocities and/or mass-loss
rates. Comparison of V1324~Sco with other gamma-ray detected novae does not
show clear signatures of either, and we conclude that a larger sample of
similarly well-observed novae is needed to understand the origin and variation
of gamma rays in novae.Comment: 26 pages, 13 figure
Temporal changes in prevalence of molecular markers mediating antimalarial drug resistance in a high malaria transmission setting in Uganda.
Standard therapy for malaria in Uganda changed from chloroquine to chloroquine + sulfadoxine-pyrimethamine in 2000, and artemether-lumefantrine in 2004, although implementation of each change was slow. Plasmodium falciparum genetic polymorphisms are associated with alterations in drug sensitivity. We followed the prevalence of drug resistance-mediating P. falciparum polymorphisms in 982 samples from Tororo, a region of high transmission intensity, collected from three successive treatment trials conducted during 2003-2012, excluding samples with known recent prior treatment. Considering transporter mutations, prevalence of the mutant pfcrt 76T, pfmdr1 86Y, and pfmdr1 1246Y alleles decreased over time. Considering antifolate mutations, the prevalence of pfdhfr 51I, 59R, and 108N, and pfdhps 437G and 540E were consistently high; pfdhfr 164L and pfdhps 581G were uncommon, but most prevalent during 2008-2010. Our data suggest sequential selective pressures as different treatments were implemented, and they highlight the importance of genetic surveillance as treatment policies change over time
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The fishing industry and Pacific coastal communities : understanding the assessment of economic impacts
People interested in economic stability or economic development in coastal communities are often interested in estimating the impact of changes or proposed changes on the economy. Such changes may result from plans, policies, or projects of public agencies, or from marketing strategies of private businesses. In coastal communities where fisheries are important, changes in fish availability due to regulatory or natural causes, closures of fish processing plants, and the development of fishing vessel facilities are examples of typical changes with important impacts on local economies. Local citizens are also interested in forecasting changes in business activity, employment, population, and public service demands.
Economic input/output (1/0) models are often used to estimate the impact of resource changes or to calculate the contributions of an industry to local economies. This publication is designed both as an introduction to input/output models and as a guide to the proper use of economic impact terminology. The use of economic jargon is minimized, and a glossary is included on page 9.
This publication grew out of concerns about the lack of understanding and improper use of input/output (1/0) models. This lack of understanding or misuse of 1/0 models is especially troublesome in situations where groups with opposing views come up with very different estimates of economic impacts. In an attempt to clarify the use of 1/0 models, the Pacific Sea Grant College Program and the Pacific Fishery Management Council held a workshop in February 1986 to discuss 1/0 models. Participants included resource economists, fishing industry representatives, and fisheries managers. This publication is one of the products of that workshop
Lymphoid aggregates that resemble tertiary lymphoid organs define a specific pathological subset in metal-on-metal hip replacements
Aseptic lymphocyte-dominated vasculitis-associated lesion (ALVAL) has been used to describe the histological lesion associated with metal-on-metal (M-M) bearings. We tested the hypothesis that the lymphoid aggregates, associated with ALVAL lesions resemble tertiary lymphoid organs (TLOs). Histopathological changes were examined in the periprosthetic tissue of 62 M-M hip replacements requiring revision surgery, with particular emphasis on the characteristics and pattern of the lymphocytic infiltrate. Immunofluorescence and immunohistochemistry were used to study the classical features of TLOs in cases where large organized lymphoid follicles were present. Synchrotron X-ray fluorescence (XRF) measurements were undertaken to detect localisation of implant derived ions/particles within the samples. Based on type of lymphocytic infiltrates, three different categories were recognised; diffuse aggregates (51%), T cell aggregates (20%), and organised lymphoid aggregates (29%). Further investigation of tissues with organised lymphoid aggregates showed that these tissues recapitulate many of the features of TLOs with T cells and B cells organised into discrete areas, the presence of follicular dendritic cells, acquisition of high endothelial venule like phenotype by blood vessels, expression of lymphoid chemokines and the presence of plasma cells. Co-localisation of implant-derived metals with lymphoid aggregates was observed. These findings suggest that in addition to the well described general foreign body reaction mediated by macrophages and a T cell mediated type IV hypersensitivity response, an under-recognized immunological reaction to metal wear debris involving B cells and the formation of tertiary lymphoid organs occurs in a distinct subset of patients with M-M implants
Clinical Trial Design - Effect of Prone Positioning on Clinical Outcomes in Infants and Children With Acute Respiratory Distress Syndrome
Purpose
This paper describes the methodology of a clinical trial of prone positioning in pediatric patients with acute lung injury (ALI). Nonrandomized studies suggest that prone positioning improves oxygenation in patients with ALI/acute respiratory distress syndrome without the risk of serious iatrogenic injury. It is not known if these improvements in oxygenation result in improvements in clinical outcomes. A clinical trial was needed to answer this question.
Materials and Methods
The pediatric prone study is a multicenter, randomized, noncrossover, controlled clinical trial. The trial is designed to test the hypothesis that at the end of 28 days, children with ALI treated with prone positioning will have more ventilator-free days than children treated with supine positioning. Secondary end points include the time to recovery of lung injury, organ failure–free days, functional outcome, adverse events, and mortality from all causes. Pediatric patients, 42 weeks postconceptual age to 18 years of age, are enrolled within 48 hours of meeting ALI criteria. Patients randomized to the prone group are positioned prone within 4 hours of randomization and remain prone for 20 hours each day during the acute phase of their illness for a maximum of 7 days. Both groups are managed according to ventilator protocol, extubation readiness testing, and sedation protocols and hemodynamic, nutrition, and skin care guidelines.
Conclusions
This paper describes the process, multidisciplinary input, and procedures used to support the design of the clinical trial, as well as the challenges faced by the clinical scientists during the conduct of the clinical trial
Tomographic Regional Cerebral Blood Flow Activation During Phoneme Detection in Normal and Aphasic Subjects
TB
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