Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
6,760
result(s) for
"Booth, Robert"
Sort by:
The Alpha-defensin Test for Periprosthetic Joint Infection Responds to a Wide Spectrum of Organisms
Background
The alpha-defensin test has been previously demonstrated to be highly accurate in the diagnosis of prosthetic joint infection (PJI), nearly matching the Musculoskeletal Infection Society definition for PJI. However, the relationship between alpha-defensin levels and differing infecting organism has not yet been investigated.
Questions/purposes
The purpose of this study is to describe the breadth of organisms that can trigger a positive synovial fluid alpha-defensin test result in the setting of PJI and also to assess the magnitude of the alpha-defensin result in terms of various pathogen characteristics.
Methods
Between December 2012 and March 2014, one laboratory processed 2319 synovial fluid samples for alpha-defensin testing. The present study reviewed the results of the 1937 samples that simultaneously had a synovial fluid culture performed; these came from 418 surgeons in 42 states. The overall culture-positive rate was 49% (244 of 498) among alpha-defensin-positive synovial fluids and 1% (19 of 1439) among alpha-defensin-negative synovial fluids. The organisms recovered from 244 alpha-defensin-positive, culture-positive fluids were recorded and grouped based on various characteristics, including Gram type, species, virulence, oral pathogenicity, and source joint. Alpha-defensin-negative samples served as uninfected controls. Median alpha-defensin levels were calculated for each group, and Dunn’s multiple comparison test for nonparametric data was used to identify any statistically significant (p < 0.05) organism-specific differences in the alpha-defensin level.
Results
The alpha-defensin test for PJI was positive in the setting of a wide spectrum of organisms typically causing PJI. The median alpha-defensin level for all 244 alpha-defensin-positive, culture-positive samples (4.7 [interquartile range {IQR}, 3.7–5.3]) was higher than negative controls (0.26 [IQR, 0.22–0.33]) with a median difference of 4.4 (p < 0.001). There were no differences in the median alpha-defensin levels when performing a multiple comparison test among Gram-positive organisms (4.7 [IQR, 3.6–5.3]), Gram-negative organisms (4.8 [IQR, 4.2–5.3]), yeast (4.1 [IQR, 2.2–5.1]), virulent organisms (4.7 [IQR, 3.8–5.2]), less virulent organisms (4.8 [IQR, 3.6–5.4]), oral pathogens (4.5 [IQR, 3.2–5.2]), knees (4.7 [IQR, 3.7–5.3]), hips (4.9 [IQR, 4.1–5.8]), or shoulders (5.3 [IQR, 4.0–10.7]) with all comparisons having a p > 0.999.
Conclusions
The alpha-defensin test provides consistent results regardless of the organism type, Gram type, species, or virulence of the organism and should be seriously considered to be a standard diagnostic tool in the evaluation for PJI. Future research should focus on the performance of this test in specific clinical scenarios such as the immediate postoperative period in the setting of severe immunocompromise and in the setting of a native joint.
Level of Evidence
Level III, diagnostic study.
Journal Article
The Alpha-defensin Test for Periprosthetic Joint Infection Outperforms the Leukocyte Esterase Test Strip
Background
Synovial fluid biomarkers have demonstrated diagnostic accuracy surpassing the currently used diagnostic tests for periprosthetic joint infection (PJI).
Questions/purposes
The purpose of this study is to directly compare the sensitivity and specificity of the synovial fluid α-defensin immunoassay to the leukocyte esterase (LE) colorimetric test strip.
Methods
Synovial fluid was collected from 46 patients meeting the inclusion criteria of this prospective diagnostic study. Synovial fluid samples were tested with both a novel synovial-fluid-optimized immunoassay for α-defensin and the LE colorimetric test strip. The Musculoskeletal Infection Society (MSIS) definition was used to classify 23 periprosthetic infections and 23 aseptic failures; this classification was used as the standard against which the two diagnostic tests were compared.
Results
The synovial fluid α-defensin immunoassay correctly predicted the MSIS classification of all patients in the study, demonstrating a sensitivity and specificity of 100% for the diagnosis of PJI. The α-defensin assay could be read for all samples, including those with blood in the synovial fluid. The leukocyte esterase test strip could not be interpreted in eight of 46 samples (17%) as a result of blood interference. Analysis of the LE strips that could be interpreted yielded a sensitivity of 69% and a specificity of 100%.
Conclusions
The synovial fluid α-defensin immunoassay outperformed the LE colorimetric test strip in this study and provided reliable results even when the LE test strip failed as a result of blood interference. The simple analytic results provided by the α-defensin immunoassay, compared with the more complex and interpretive nature of both the MSIS criteria and LE colorimetric test strip, make it a highly attractive diagnostic tool.
Level of Evidence
Level II, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.
Journal Article
WikiLeaks : inside Julian Assange's war on secrecy
Traces the history of the online organization WikiLeaks, which released thousands of previously secret or classified documents from numerous government agencies, and examines its impact on world politics and freedom of information.
Book
Effective descriptions of bosonic systems can be considered complete
Bosonic statistics give rise to remarkable phenomena, from the Hong–Ou–Mandel effect to Bose–Einstein condensation, with applications spanning fundamental science to quantum technologies. Modeling bosonic systems relies heavily on effective descriptions: typically, truncating their infinite-dimensional state space or restricting their dynamics to a simple class of Hamiltonians, such as polynomials of canonical operators. However, many natural bosonic Hamiltonians do not belong to these simple classes, and some quantum effects harnessed by bosonic computers inherently require infinite-dimensional spaces. Can we trust that results obtained with such simplifying assumptions capture real effects? We solve this outstanding problem, showing that these effective descriptions do correctly capture the physics of bosonic systems. Our technical contributions are twofold: firstly, we prove that any physical bosonic unitary evolution can be accurately approximated by a finite-dimensional unitary evolution; secondly, we show that any finite-dimensional unitary evolution can be generated exactly by a bosonic Hamiltonian that is a polynomial of canonical operators. Beyond their fundamental significance, our results have implications for classical and quantum simulations of bosonic systems, provide universal methods for engineering bosonic quantum states and Hamiltonians, show that polynomial Hamiltonians generate universal gate sets for quantum computing over bosonic modes, and lead to a bosonic Solovay–Kitaev theorem.
Bosonic systems live in an infinite-dimensional space, and in order to be able to describe them one usually reduces it to an effective finite dimension or constrain the dynamics in some way, but it is not fully understood whether this captures all the physics at play. Here, the authors fill this gap showing that such representations can successfully and rigorously approximate bosonic physics.
Journal Article
علم الأحياء بالتقصي : مساق في علم الأحياء التجريبي
يتناول كتاب (علم الأحياء بالتقصي : مساق في علم الأحياء التجريبي) والذي قام بتأليفه (روبرت كلارك) في مجلد من القطع المتوسط موضوع (علم الأحياء التجريبي واللافقاريات) مستعرضا المحتويات التالية : الفصل الأول : توزيع الكائنات الحية، الفصل الثاني : الحيوانات والنباتات والأمكنة، الفصل الثالث : تنوع الأنظمة البيئية، الفصل الرابع : دراسة التنوع، الفصل الخامس : وحدات الحياة، الفصل السادس : النمو، الفصل السابع : إنجاز العمل، الفصل الثامن : الطاقة من الشمس، الفصل التاسع : طرق انتقال الطاقة، الفصل العاشر : تحرر الطاقة، الفصل الحادي : عشر المواد بين الحياة والموت.
Book
The Neotoma Paleoecology Database, a multiproxy, international, community-curated data resource
The Neotoma Paleoecology Database is a community-curated data resource that supports interdisciplinary global change research by enabling broad-scale studies of taxon and community diversity, distributions, and dynamics during the large environmental changes of the past. By consolidating many kinds of data into a common repository, Neotoma lowers costs of paleodata management, makes paleoecological data openly available, and offers a high-quality, curated resource. Neotoma’s distributed scientific governance model is flexible and scalable, with many open pathways for participation by new members, data contributors, stewards, and research communities. The Neotoma data model supports, or can be extended to support, any kind of paleoecological or paleoenvironmental data from sedimentary archives. Data additions to Neotoma are growing and now include >3.8 million observations, >17,000 datasets, and >9200 sites. Dataset types currently include fossil pollen, vertebrates, diatoms, ostracodes, macroinvertebrates, plant macrofossils, insects, testate amoebae, geochronological data, and the recently added organic biomarkers, stable isotopes, and specimen-level data. Multiple avenues exist to obtain Neotoma data, including the Explorer map-based interface, an application programming interface, the neotoma R package, and digital object identifiers. As the volume and variety of scientific data grow, community-curated data resources such as Neotoma have become foundational infrastructure for big data science.
Journal Article
Superman Action Comics Rebirth deluxe edition
\"Superman returns to Metropolis just in time to meet the city of tomorrow's newest protector: Lex Luthor. But it's not long before these dueling titans meet someone unexpected -- the new Clark Kent! The two arch-enemies must put aside their differences and face the common threat of Doomsday, as Jimmy Olsen and the Planet staff try to uncover the truth: who is the man claiming to be Clark Kent?\"-- Provided by publisher.
Book
Ecology and the ratchet of events: Climate variability, niche dimensions, and species distributions
Climate change in the coming centuries will be characterized by interannual, decadal, and multidecadal fluctuations superimposed on anthropogenic trends. Predicting ecological and biogeographic responses to these changes constitutes an immense challenge for ecologists. Perspectives from climatic and ecological history indicate that responses will be laden with contingencies, resulting from episodic climatic events interacting with demographic and colonization events. This effect is compounded by the dependency of environmental sensitivity upon life-stage for many species. Climate variables often used in empirical niche models may become decoupled from the proximal variables that directly influence individuals and populations. Greater predictive capacity, and more-fundamental ecological and biogeographic understanding, will come from integration of correlational niche modeling with mechanistic niche modeling, dynamic ecological modeling, targeted experiments, and systematic observations of past and present patterns and dynamics.
Journal Article