14,471 research outputs found
Triterpenoids
This review covers the isolation and structure determination of triterpenoids reported during 2012 including squalene derivatives, lanostanes, holostanes, cycloartanes, cucurbitanes, dammaranes, euphanes, tirucallanes, tetranortriterpenoids, quassinoids, lupanes, oleananes, friedelanes, ursanes, hopanes, serratanes, isomalabaricanes and saponins; 348 references are cited
Beyond Chernobyl: Radiating A New Word Meaning Mistrust Authentic human development by ecological and transnational moral interdependence (Solicitudo Rei Socialis, 1987)
Risk of subsequent joint arthroplasty in contralateral or different joint after index shoulder, hip, or knee arthroplasty: Association with index joint, demographics, and patient-specific factors
A comparative study compiled from a survey taken in Middleton, Rhode Island concerning educational experiences for preschool children in the home,
Thesis (M.A.)--Boston Universit
Outcomes from conservative treatment of shoulder idiopathic adhesive capsulitis and factors associated with developing contralateral disease
Substituent effects on the nitrogen-15 and carbon-13 shieldings of some N-arylguanidinium chlorides
The 13C and 15N chemical shifts of five N-arylguanidinium chlorides carrying polar substituents, ranging in character from 4-methoxy to 4-nitro groups, have been determined by NMR spectroscopy at the natural-abundance level of 13C and 15N in dimethyl sulfoxide solution. Comparison of the 13C shifts of these salts with those of monosubstituted benzenes shows that the guanidinium group induces an average downfield shift of -5.8 ppm of the resonance of the aryl carbon to which it is attached (C1), an average upfield shift of +4.2 ppm for C2 and C6, and a small upfield shift of +1.9 ppm for C4. The shifts of C3 and C5 are small and erratic relative to the corresponding carbons in monosubstituted benzenes. The 15N resonances of the guanidinium nitrogens are quite sensitive to electric effects resulting from substitution of polar groups at C4. The 15N shift of the ==NAr nitrogen relative to that of the salts suggests that the predominant tautomer for N-arylguanidines is (H2N)2C==NAr. The 15N shifts of the (NH2) 2 nitrogens correlate rather well with σp- parameters, whereas the shifts of the -NHAr nitrogens seem to correlate only with R values derived from the σp- substituent constants
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Deterministic Separation of Cancer Cells from Blood at 10 mL/min
Circulating tumor cells (CTCs) and circulating clusters of cancer and stromal cells have been identified in the blood of patients with malignant cancer and can be used as a diagnostic for disease severity, assess the efficacy of different treatment strategies and possibly determine the eventual location of metastatic invasions for possible treatment. There is thus a critical need to isolate, propagate and characterize viable CTCs and clusters. Here, we present a microfluidic device for mL/min flow rate, continuous-flow capture of viable CTCs from blood using deterministic lateral displacement arrays. We show here that a deterministic bump array can be designed such that it will isolate with efficiency greater than 85% CTCs over a large range in sizes from millimeter volume clinical blood samples in minutes, with no effect on cell vitality so that further culturing and analysis of the cells can be carried out
Noncooperatively Optimized Tolerance: Decentralized Strategic Optimization in Complex Systems
We introduce noncooperatively optimized tolerance (NOT), a generalization of
highly optimized tolerance (HOT) that involves strategic (game theoretic)
interactions between parties in a complex system. We illustrate our model in
the forest fire (percolation) framework. As the number of players increases,
our model retains features of HOT, such as robustness, high yield combined with
high density, and self-dissimilar landscapes, but also develops features of
self-organized criticality (SOC) when the number of players is large enough.
For example, the forest landscape becomes increasingly homogeneous and
protection from adverse events (lightning strikes) becomes less closely
correlated with the spatial distribution of these events. While HOT is a
special case of our model, the resemblance to SOC is only partial; for example,
the distribution of cascades, while becoming increasingly heavy-tailed as the
number of players increases, also deviates more significantly from a power law
in this regime. Surprisingly, the system retains considerable robustness even
as it becomes fractured, due in part to emergent cooperation between
neighboring players. At the same time, increasing homogeneity promotes
resilience against changes in the lightning distribution, giving rise to
intermediate regimes where the system is robust to a particular distribution of
adverse events, yet not very fragile to changes
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