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31.
Derk Brouwer Birgit van Duuren-Stuurman Markus Berges Elzbieta Jankowska Delphine Bard Dave Mark 《Journal of nanoparticle research》2009,11(8):1867-1881
In the past few years, an increasing number of studies on workplace air measurements on manufactured nano-materials and -objects
have been published. Most of the studies had a more explorative character, so a direct interpretation to workers” exposure
for a given exposure situation, activity, or process is not a straight-forward process. In general, the studies use a quite
similar package of devices for near real-time monitoring of particle number- and mass concentration in size ranges <100 nm
up to 10 μm, and the collection of samples for off-line characterization of air samples. Various approaches for addressing
background concentrations and its use to indicate the potential for exposure to nano-objects could be observed. Within the
EU-sponsored NANOSH project, a harmonized approach for measurement strategy, data analysis and reporting was developed. In
addition to time/activity–concentration profiles as reported by most studies, this approach enables a first step to estimate
the potential for exposure to manufactured nano-objects, more quantitatively. The NANOSH data will be collated into a base,
which may form the starting point for a harmonized database facilitating overall analysis in near future, to derive estimates
for exposure for several exposure situations. 相似文献
32.
In this editorial, we set out the aims in the call to publish papers on informal statistical inference, randomness, modelling and risk. We discuss how the papers published in this issue have responded to those aims. In particular, we note how the nine papers contribute to some of the major debates in mathematics and statistics education, often taking contrasting positions. Such debates range across: (1) whether knowledge is fractured or takes the form of mental models; (2) heuristic or intuitive thinking versus operational thinking as for example in dual process theory; (3) the role of different epistemic resources, such as perceptions, modelling, imagery, in the development of probabilistic reasoning; (4) how design and situation impact upon probabilistic learning. 相似文献
33.
Wei-Gang Hu Scott Jager Damon Chau Dave Mah Les P. Nagata 《Applied biochemistry and biotechnology》2010,160(4):1206-1216
In order to develop a recombinant full-length human anti-botulinum neurotoxin A (BoNT/A) antibody, human peripheral blood
mononuclear cells (PBMC) were collected from three healthy volunteers and induced for BoNT/A-specific immune response by in
vitro immunization. The genes encoding human Fd fragment, consisting of antibody heavy chain variable region and constant
region 1 with the genes encoding antibody light chain, were cloned from the immunized PBMC. Afterwards, one combinatory human
antigen-binding fragment (Fab) library was constructed using a lambda phage vector system. The size of the constructed library
was approximately 105
Escherichia coli transformants. After screening the library by BoNT/A antigen using a plaque lifting with immunostaining approach, 55 clones
were identified as positive. The Fab gene of the most reactive clone exhibiting particularly strong BoNT/A binding signal
was further subcloned into a full-length human IgG1 antibody gene template in an adenoviral expression vector, in which the
heavy and light chains were linked by a foot-and-mouth-disease virus-derived 2A self-cleavage peptide under a single promoter.
After the full-length human IgG1 was expressed in mammalian cells and purified with protein L column, sodium dodecyl sulfate-polyacrylamide
gel electrophoresis showed that the heavy and light chains of the antibody were cleaved completely. The affinity expressed
as the dissociation constant (K
d) for the recombinant human antibody to bind to BoNT/A was determined by indirect enzyme-linked immunosorbent assay and results
confirmed that the recombinant full-length human antibody retained BoNT/A-binding specificity with K
d value of 10−7 M. 相似文献
34.
Dave KIELPINSKI 《Frontiers of Physics in China》2008,3(4):365-381
Atomic ions trapped in ultra-high vacuum form an especially well-understood and useful physical system for quantum information
processing. They provide excellent shielding of quantum information from environmental noise, while strong, well-controlled
laser interactions readily provide quantum logic gates. A number of basic quantum information protocols have been demonstrated
with trapped ions. Much current work aims at the construction of large-scale ion-trap quantum computers using complex microfabricated
trap arrays. Several groups are also actively pursuing quantum interfacing of trapped ions with photons.
相似文献
35.
Editorial
Focus on H/D exchange of proteins in solution 相似文献36.
37.
Maximum likelihood estimates for the parameters involved in a stationary M/M/2 queueing process with heterogeneous servers are obtained to make inferences about arrival and service rates. The queue is considered to be in a state of equilibrium. One further extension is discussed. 相似文献
38.
The problem of returning or of selling the inventory excess to optimal stock level is considered for deteriorating items. Two inventory models, viz. the infinite and the finite horizon models, are developed, in which the deterioration is assumed to be a constant fraction of the on hand inventory. Both the models are developed under the assumptions of instantaneous delivery and no shortages. When there is no deterioration, the developed models are related to the corresponding inventory models for non-deteriorating items. Examples are given to illustrate the derived results. 相似文献
39.
Chad?A?Dickey Marcia?N?Gordon Donna?M?Wilcock Donna?L?Herber Melissa?J?Freeman Dave?MorganEmail author 《BMC neuroscience》2005,6(1):7
Background
The pathology of Alzheimer's disease (AD) is comprised of extracellular amyloid plaques, intracellular tau tangles, dystrophic neurites and neurodegeneration. The mechanisms by which these various pathological features arise are under intense investigation. Here, expanding upon pilot gene expression studies, we have further analyzed the relationship between Na+/K+ ATPase and amyloid using APP+PS1 transgenic mice, a model that develops amyloid plaques and memory deficits in the absence of tangle formation and neuronal or synaptic loss. 相似文献40.
For and , we give explicit, practical conditions that determine whether or not a closed, connected subgroup of has the property that there exists a compact subset of with . To do this, we fix a Cartan decomposition of , and then carry out an approximate calculation of for each closed, connected subgroup of .