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21.
Noninvasive diagnostic studies, i.e., sputum gram stain, sputum culture, blood culture and antigen detection assays will assist the clinician in the selection of initial antimicrobial therapy in some patients. These tests may be even more valuable in adjusting treatment regimens to prevent the use of broad spectrum antimicrobial agents as routine therapy. 相似文献
22.
Maureen G. Walsh Brian F. Lantry Brent Boscarino Kelly Bowen Jocelyn Gerlofsma Ted Schaner Richard Back Jennifer Questel A. Garry Smythe Roberta Cap Michael Goehle Bryan Young Marc Chalupnicki James H. Johnson James E. McKenna Jr. 《Journal of Great Lakes research》2010
Hemimysis anomala, a Ponto-Caspian littoral mysid, is an emerging Great Lakes invader that was discovered in Lakes Michigan and Ontario in 2006. Similar to the native mysid Mysis diluviana, Hemimysis exhibits a diel vertical migration pattern but generally inhabits shallower and warmer waters than M. diluviana. Because basic information on the distribution, habitat use, and biology of Hemimysis in the Great Lakes is scarce, the potential for food web disruption by Hemimysis cannot easily be predicted. Preliminary observations indicate widespread invasion of Hemimysis in Lake Ontario. In this study, we confirm the presence of Hemimysis at sites spanning the northern and southern shores of Lake Ontario and the presence of the individuals during winter months. In one horizontal tow in November 2007, over 26,000 individuals were collected with a length range of 4.4 to 9.0 mm and an average caloric density of 611 cal/g wet weight. The most effective methods for sampling Hemimysis were horizontal tows with either a zooplankton net in the water column or a benthic sled near the lake bottom. Although more quantitative data on the life history and distribution of this species is necessary, our preliminary observations support the prediction that the potential for Hemimysis to impact the nearshore food web in Lake Ontario appears high. 相似文献
23.
24.
Estimating production data for five engineered nanomaterials as a basis for exposure assessment 总被引:2,自引:0,他引:2
The magnitude of engineered nanomaterials (ENMs) being produced and potentially released to the environment is a crucial and thus far unknown input to exposure assessment. This work estimates upper and lower bound annual United States production quantities for 5 classes of ENMs. A variety of sources were culled to identify companies producing source ENM products and determine production volumes. Using refining assumptions to attribute production levels from companies with more reliable estimates to companies with little to no data, ranges of U.S. production quantities were projected for each of the 5 ENMs. The quality of data is also analyzed; the percentage of companies for which data were available (via Web sites, patents, or direct communication) or unavailable (and thus extrapolated from other companies' data) is presented. 相似文献
25.
Hunter Richard H.; Ritchie A. Jocelyn; Spaulding William D. 《Canadian Metallurgical Quarterly》2005,36(5):467
This article describes 2 important practice considerations affirmed in the U.S. Supreme Court's Sell v. United States (2002) decision: (a) the importance of providing least restrictive services prior to interventions that violate patients' liberty interests, and (b) contextual and environmental factors may be considered in clinical determinations of dangerousness. The psychological treatment of behavior disorders fall within the purview of least restrictive or intrusive interventions compared with the involuntary administration of psychoactive medications. To legitimately comply with the least restrictive criterion, the provision of psychological services is essential. This long-held criterion is rarely acknowledged today as providers use restricted service arrays and attempt to resolve complex and co-occurring behavior problems with medications and restraints. Less restrictive psychological interventions are required for effective treatment of challenging behaviors. A 2nd significant implication lies in the court's affirmation that it is legitimate to consider contextual factors such as history and current environmental conditions in determining dangerousness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
26.
This paper is a general overview of the S
project, run at Blaise Pascal University between 1996 and 2002. The main goal of the S
project was to demonstrate the applicability of skeleton-based parallel programming techniques to the fast prototyping of reactive vision applications. This project has produced several versions of a full-fledged integrated parallel programming environment (PPE). These PPEs have been used to implement realistic vision applications, such as road following or vehicle tracking for assisted driving, on embedded parallel platforms embarked on semi-autonomous vehicles. All versions of S
share a common front-end and repertoire of skeletons––presented in previous papers––but differ in the techniques used for implementing skeletons. This paper focuses on these implementation issues, by making a comparative survey, according to a set of four criteria (efficiency, expressivity, portability, predictability), of these implementation techniques. It also gives an account of the lessons we have learned, both when dealing with these implementation issues and when using the resulting tools for prototyping vision applications. 相似文献
27.
28.
Fourteen commonly available types of cane and palm sugar were analysed for antioxidant activity using cyclic voltammetry. Five of the sugars, dissolved in phosphate buffer, showed anodic current peaks which were indicative of antioxidant activity. The rank order of these sugars was: gula anau > gula merah > China rock honey sugar > soft brown sugar > raw sugar. Gula anau is an unrefined palm sugar, while the other four are from sugarcane. Soft brown sugar and raw sugar are coated brown sugars. The China rock honey sugar contained chrysanthemum flowers, and its antioxidant properties appear to be due to these flowers and not to the sugar per se. Pure white sugar, other rock sugars and rock honey sugars (all refined from cane) as well as gula Melaka, an unrefined rock sugar from palm trees, had no observable antioxidant activity. It is concluded that, from a nutritional point of view, using gula anau as a sweetener or ingredient in foods or drinks has an added benefit owing to its antioxidant content. 相似文献
29.
The citrus leafminer is an important vector of citrus canker in many of the major citrus production areas of the world. (7Z,11Z)-Hexadecadienal was reported as a sex attractant for this insect in the 1980s, based on trap catches during pheromone screening
trials in Japan. However, attempts to reproduce this work in other areas of the world have not been successful. We report
here that (7Z,11Z)-hexadecadienal is only one component of the pheromone, with the other critical component being the analogous trienal, (7Z,11Z,13E)-hexadecatrienal. Both compounds were identified in the effluvia from live female moths by coupled gas chromatography (GC)-electroantennography
using nonpolar and polar GC columns, and the identifications were confirmed by comparisons of mass spectra with those of authentic
standards. Stereoisomers of the two compounds, and a number of analogs, were synthesized to confirm the identifications. In
field trials, neither compound alone was attractive to male moths, but blends of the two were highly attractive, with thousands
of insects being caught per trial. Addition of the isomeric (7Z,11Z,13Z)-hexadecatrienal inhibited attraction to the two-component blend.
Electronic Supplementary Material Supplementary material is available for this article at and accessible for authorized users.
This paper and the preceding paper (Leal et al.) were submitted within a few days of each other. The editors and the authors
agreed that they should be published in tandem. 相似文献
30.
Joshua Rodstein J. Steven McElfresh James D. Barbour Ann M. Ray Lawrence M. Hanks Jocelyn G. Millar 《Journal of chemical ecology》2009,35(5):590-600
Females of the large cerambycid beetle Prionus californicus produce a powerful sex pheromone that attracts males. The pheromone was adsorbed on solid phase microextraction (SPME) fibers
inserted into the ovipositor sheath and analyzed by coupled gas chromatography-electroantennogram detection and GC-mass spectrometry.
The pheromone was identified as an isomer of 3,5-dimethyldodecanoic acid by a combination of retention index comparisons and
mass spectral interpretation. The mass spectrum was misleading because it exhibited enlarged fragment ions that were not representative
of branch points or other obvious stabilizing structural elements. The structure was verified by synthesis of 3,5-dimethyldodecanoic
acid as a mixture of all four possible isomers, and this mixture was highly attractive to male beetles in field bioassays.
The SPME extracts also contained several other compounds that were tentatively identified as chain-extended homologs of the
main pheromone component. This pheromone should prove useful for sampling and management of the beetle, which is an important
pest of hops, and an occasional pest in a variety of orchard crops. Although this is the first female-produced pheromone to
be identified from the Cerambycidae, there is considerable evidence for pheromone production by females of other species in the subfamily Prioninae. Thus, this pheromone and the associated methodology used in its identification should be useful in the identification of
female-produced attractant pheromones from other members of the subfamily.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献