4,325 research outputs found
Carcinoembryonic antigen and glucose phosphate isomerase in a human colonic cancer model (GW-39).
Levels of carcinoembryonic antigen (CEA) and glucose phosphate isomerase (GPI) have been compared in the circulating blood of hamsters bearing intra-muscular grafts of GW-39 human colonic tumour. CEA in the sera of GW-39 tumour-bearing hamsters ranged from 2-6 to 8-4 ng/ml (mean = 4-5 +/- 1-7 ng/ml). GPI in the sera of normal hamsters ranged from 332 to 749 iu/1 (mean = 602 +/- 110 iu/1) while those with 14-week-old intra-muscular grafts of a hamster amelanotic melanoma, (A.Mel.3), or GW-39 human colonic carcinoma had a range of 664 to 1267 iu/1 (mean = 1024 +/- 220 iu/1) and 1430 to 4719 iu/1 (mean = 2065 +/- 601 iu/1) respectively. Thus, the ratio of enzyme activity in GW-39, A.Mel.3, and normal hamsters was 3-4:1-7:1, indicating a significant elevation (P less than 0-01) in animals bearing a human colon carcinoma or a hamster melanoma, with particularly high values obtained in hamsters with GW-39. Sequential determinations of CEA and GPI in a group of hamsters transplanted intra-muscularly with GW-39 tumours revealed that both markers increased proportionately with duration of tumour growth, suggesting that both serum CEA and GPI may be used as measures of tumour growth. The concentration of GPI in GW-39 human colonic carcinoma xenografts was also significantly higher than that measured in normal human colon, primary human colonic cancer, or normal hamster tissues. These results support the view that GPI, in addition to CEA, is a quantitatively increased marker in this tumour model, and is liberated into the circulation in proportion to the increase in tumour mass
Particle displacements in the elastic deformation of amorphous materials: local fluctuations vs. non-affine field
We study the local disorder in the deformation of amorphous materials by
decomposing the particle displacements into a continuous, inhomogeneous field
and the corresponding fluctuations. We compare these fields to the commonly
used non-affine displacements in an elastically deformed 2D Lennard-Jones
glass. Unlike the non-affine field, the fluctuations are very localized, and
exhibit a much smaller (and system size independent) correlation length, on the
order of a particle diameter, supporting the applicability of the notion of
local "defects" to such materials. We propose a scalar "noise" field to
characterize the fluctuations, as an additional field for extended continuum
models, e.g., to describe the localized irreversible events observed during
plastic deformation.Comment: Minor corrections to match the published versio
Potential of Peroxisome Proliferator-Activated Receptor Gamma Antagonist Compounds as Therapeutic Agents for a Wide Range of Cancer Types
PPARĪ³ is a therapeutic target that has been exploited for
treatment of type II diabetes mellitus (T2DM) with agonist drugs.
Since PPARĪ³ is expressed by many hematopoietic, mesodermal and
epithelial cancers, agonist drugs were tested and shown to have
both preclinical and clinical anticancer activities. While
preclinical activity has been observed in many cancer types,
clinical activity has been observed only in pilot and phase II
trials in liposarcoma and prostate cancer. Most studies address
agonist compounds, with substantially fewer reports on anticancer
effects of PPARĪ³ antagonists. In cancer model systems, some
effects of PPARĪ³ agonists were not inhibited by PPARĪ³ antagonists,
suggesting noncanonical or PPARĪ³-independent mechanisms. In
addition, PPARĪ³ antagonists, such as T0070907 and GW9662, have
exhibited antiproliferative effects on a broad range of
hematopoietic and epithelial cell lines, usually with greater
potency than agonists. Also, additive antiproliferative effects
of combinations of agonist plus antagonist drugs were observed.
Finally, there are preclinical in vivo data showing that
antagonist compounds can be administered safely, with favorable
metabolic effects as well as antitumor effects. Since PPARĪ³
antagonists represent a new drug class that holds promise as a
broadly applicable therapeutic approach for cancer treatment, it
is the subject of this review
Force Chains, Microelasticity and Macroelasticity
It has been claimed that quasistatic granular materials, as well as nanoscale
materials, exhibit departures from elasticity even at small loadings. It is
demonstrated, using 2D and 3D models with interparticle harmonic interactions,
that such departures are expected at small scales [below O(100) particle
diameters], at which continuum elasticity is invalid, and vanish at large
scales. The models exhibit force chains on small scales, and force and stress
distributions which agree with experimental findings. Effects of anisotropy,
disorder and boundary conditions are discussed as well.Comment: 4 pages, 11 figures, RevTeX 4, revised and resubmitted to Phys. Rev.
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A Comparison of Blocking Methods for Record Linkage
Record linkage seeks to merge databases and to remove duplicates when unique
identifiers are not available. Most approaches use blocking techniques to
reduce the computational complexity associated with record linkage. We review
traditional blocking techniques, which typically partition the records
according to a set of field attributes, and consider two variants of a method
known as locality sensitive hashing, sometimes referred to as "private
blocking." We compare these approaches in terms of their recall, reduction
ratio, and computational complexity. We evaluate these methods using different
synthetic datafiles and conclude with a discussion of privacy-related issues.Comment: 22 pages, 2 tables, 7 figure
Supply Chain Disruption Costs Study in International Containerised Maritime Transportation
The global economy relies highly on international trade, and the international maritime transport system acts as the lifeblood carrying and transporting materials and goods globally, realizing the economy globalization in an effective and efficient way. However, globalization increases the interdependence and complexity of global supply chains and drives it to be more vulnerable to disruptions. Meanwhile, the international marine transport system is a complex and intertwined system exposed to high risks and decreased safety due to its very accessibility and operational flexibility. Thereby, global supply chains integrated with international maritime transportation systems are inherently vulnerable to various disruptions. Studies of supply chain disruptions particularly quantifying transport related disruption costs are becoming increasingly important. However, research on maritime transport related supply chain disruptions, in particular, quantifying its disruption costs is under-represented in the transport literature, due largely to the features of supply chain disruptions, but also because of the complexity of maritime related supply chains. Current research in transportation has tended to concentrate on shippersā transport mode choice and port selection. In the context of a global market, however, the behaviour of maritime containerised shippers has to be viewed as a complex decision and an integral element of the supply chain management strategy. Those shippersā transportation choice decisions should be emphasized and studied to reveal their behaviour changes between normal operations and disruption circumstance. This research adds to the paucity work on investigating the maritime transport related supply chain disruptions and quantifying its disruption costs based on shippersā maritime transportation choice behaviour. It presents the results of a microanalysis of freight transport choice decisions in an international containerised maritime transport chain context. The Latent Class Model (LCM) is applied to identify the key service attributes and its preference heterogeneity in maritime transportation and to estimate the marginal values for the quality of maritime transport service with and without a disruption, simultaneously, quantifying the disruption costs through comparing each attributeās marginal value difference between normal and disruption operations. The Seemingly Unrelated Regression model (SURE) is utilized to explore the sources influencing shippersā preference heterogeneities. In doing so, we are able to gain an understanding as to where and how much should be invested in order to facilitate recovery in the case of a disruption based on the view of the maritime participantsā perspectives. The research results confirm freight rate, transit time, reliability, damage rate, and frequency as the key service attributes influencing shippersā transport choice. They also reveal shippersā VOT increase by more than four-times, VOR nearly double, and VOD increase about twenty percent if a disruption takes place, and identify shippersā transport decisions vary with its product, shipment, company and supply chain characteristics no matter with or without a disruption. This research quantifies the costs of supply chain disruption in containerised maritime transport context for the first time, and its results provide useful industrial implications for maritime transport chain related parties
Stress response inside perturbed particle assemblies
The effect of structural disorder on the stress response inside three
dimensional particle assemblies is studied using computer simulations of
frictionless sphere packings. Upon applying a localised, perturbative force
within the packings, the resulting {\it Green's} function response is mapped
inside the different assemblies, thus providing an explicit view as to how the
imposed perturbation is transmitted through the packing. In weakly disordered
arrays, the resulting transmission of forces is of the double-peak variety, but
with peak widths scaling linearly with distance from the source of the
perturbation. This behaviour is consistent with an anisotropic elasticity
response profile. Increasing the disorder distorts the response function until
a single-peak response is obtained for fully disordered packings consistent
with an isotropic description.Comment: 8 pages, 7 figure captions To appear in Granular Matte
Modelling diffusion of innovations in a social network
A new simple model of diffusion of innovations in a social network with
upgrading costs is introduced. Agents are characterized by a single real
variable, their technological level. According to local information agents
decide whether to upgrade their level or not balancing their possible benefit
with the upgrading cost. A critical point where technological avalanches
display a power-law behavior is also found. This critical point is
characterized by a macroscopic observable that turns out to optimize
technological growth in the stationary state. Analytical results supporting our
findings are found for the globally coupled case.Comment: 4 pages, 5 figures. Final version accepted in PR
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