217 research outputs found
Enhanced structural correlations accelerate diffusion in charge-stabilized colloidal suspensions
Theoretical calculations for colloidal charge-stabilized and hard sphere
suspensions show that hydrodynamic interactions yield a qualitatively different
particle concentration dependence of the short-time self-diffusion coefficient.
The effect, however, is numerically small and hardly accessible by conventional
light scattering experiments. Applying multiple-scattering decorrelation
equipment and a careful data analysis we show that the theoretical prediction
for charged particles is in agreement with our experimental results from
aqueous polystyrene latex suspensions.Comment: 1 ps-file (MS-Word), 14 page
Serial native T1- and T2-mapping to quantitatively monitor resorption of myocardial edema following acute myocardial infarction
Assessing personality in San Joaquin kit fox in situ: efficacy of field-based experimental methods and implications for conservation management
Utilisation of animal personality has potential benefit for conservation management. Due to logistics of robust behavioural evaluation in situ, the majority of studies on wild animals involve taking animals into captivity for testing, potentially compromising results. Three in situ tests for evaluation of boldness in San Joaquin kit fox (Vulpes macrotis mutica) were developed (ENOT: extended novel object test; RNOT: rapid novel object test; TH: trap/handling test). Each test successfully identified variation in boldness within its target age class(es). The TH test was suitable for use across all age classes. Tests were assessed for in situ suitability and for quantity/quality of data yielded. ENOT was rated as requiring high levels of time, cost and labour with greater likelihood of failure. However, it was rated highly for data quantity/quality. The TH test was rated as requiring little time, labour and cost, but yielding lower quality data. RNOT was rated in the middle. Each test had merit and could be adapted to suit project or species constraints. We recommend field-based evaluation of personality, reducing removal of animals from the wild and facilitating routine incorporation of personality assessment into conservation projects
Optimal Energy Investment and R&D Strategies to Stabilise Greenhouse Gas Atmospheric Concentrations
Cost analysis of nondeterministic probabilistic programs
We consider the problem of expected cost analysis over nondeterministic probabilistic programs,
which aims at automated methods for analyzing the resource-usage of such programs.
Previous approaches for this problem could only handle nonnegative bounded costs.
However, in many scenarios, such as queuing networks or analysis of cryptocurrency protocols,
both positive and negative costs are necessary and the costs are unbounded as well.
In this work, we present a sound and efficient approach to obtain polynomial bounds on the
expected accumulated cost of nondeterministic probabilistic programs.
Our approach can handle (a) general positive and negative costs with bounded updates in
variables; and (b) nonnegative costs with general updates to variables.
We show that several natural examples which could not be
handled by previous approaches are captured in our framework.
Moreover, our approach leads to an efficient polynomial-time algorithm, while no
previous approach for cost analysis of probabilistic programs could guarantee polynomial runtime.
Finally, we show the effectiveness of our approach using experimental results on a variety of programs for which we efficiently synthesize tight resource-usage bounds
Cost Analysis of Nondeterministic Probabilistic Programs
We consider the problem of expected cost analysis over nondeterministic
probabilistic programs, which aims at automated methods for analyzing the
resource-usage of such programs. Previous approaches for this problem could
only handle nonnegative bounded costs. However, in many scenarios, such as
queuing networks or analysis of cryptocurrency protocols, both positive and
negative costs are necessary and the costs are unbounded as well.
In this work, we present a sound and efficient approach to obtain polynomial
bounds on the expected accumulated cost of nondeterministic probabilistic
programs. Our approach can handle (a) general positive and negative costs with
bounded updates in variables; and (b) nonnegative costs with general updates to
variables. We show that several natural examples which could not be handled by
previous approaches are captured in our framework.
Moreover, our approach leads to an efficient polynomial-time algorithm, while
no previous approach for cost analysis of probabilistic programs could
guarantee polynomial runtime. Finally, we show the effectiveness of our
approach by presenting experimental results on a variety of programs, motivated
by real-world applications, for which we efficiently synthesize tight
resource-usage bounds.Comment: A conference version will appear in the 40th ACM Conference on
Programming Language Design and Implementation (PLDI 2019
Dihydropyrimidine Dehydrogenase Testing prior to Treatment with 5-Fluorouracil, Capecitabine, and Tegafur: A Consensus Paper
Background: 5-Fluorouracil (FU) is one of the most commonly used cytostatic drugs in the systemic treatment of
cancer. Treatment with FU may cause severe or life-threatening side effects and the treatment-related mortality rate is 0.2–1.0%. Summary: Among other risk factors associated
with increased toxicity, a genetic deficiency in dihydropyrimidine dehydrogenase (DPD), an enzyme responsible for
the metabolism of FU, is well known. This is due to variants
in the DPD gene (DPYD). Up to 9% of European patients carry a DPD gene variant that decreases enzyme activity, and
DPD is completely lacking in approximately 0.5% of patients.
Here we describe the clinical and genetic background and
summarize recommendations for the genetic testing and
tailoring of treatment with 5-FU derivatives. The statement
was developed as a consensus statement organized by the
German Society for Hematology and Medical Oncology in
cooperation with 13 medical associations from Austria, Germany, and Switzerland. Key Messages: (i) Patients should be
tested for the 4 most common genetic DPYD variants before
treatment with drugs containing FU. (ii) Testing forms the
basis for a differentiated, risk-adapted algorithm with recommendations for treatment with FU-containing drugs. (iii)
Testing may optionally be supplemented by therapeutic
drug monitorin
Identifying the robust economic, geographical and political determinants of FDI : an Extreme Bounds Analysis
Understanding what determines Foreign Direct Investment (FDI) inflows remains a primary concern of economists and policy makers; yet the uncertainty surrounding FDI theories and empirical approaches has created ambiguity regarding the determinants of FDI. This paper applies Extreme Bounds Analysis to identify the robust determinants of FDI using panel data covering 168 countries from 1970 to 2006. We consider 58 potential economic, geographic and political determinants and find that almost one-third are robust, including: openness, education, government spending, corporate tax rate, infrastructure, experience of conflict, democratic governance, natural resources, geographic location, number of borders, coastal location and language
α2,3-Sialyltransferase ST3Gal III Modulates Pancreatic Cancer Cell Motility and Adhesion In Vitro and Enhances Its Metastatic Potential In Vivo
Background: Cell surface sialylation is emerging as an important feature of cancer cell metastasis. Sialyltransferase expression has been reported to be altered in tumours and may account for the formation of sialylated tumour antigens. We have focused on the influence of alpha-2,3-sialyltransferase ST3Gal III in key steps of the pancreatic tumorigenic process. Methodology/Principal Findings: ST3Gal III overexpressing pancreatic adenocarcinoma cell lines Capan-1 and MDAPanc-28 were generated. They showed an increase of the tumour associated antigen sialyl-Lewis x. The transfectants ’ E-selectin binding capacity was proportional to cell surface sialyl-Lewis x levels. Cellular migration positively correlated with ST3Gal III and sialyl-Lewis x levels. Moreover, intrasplenic injection of the ST3Gal III transfected cells into athymic nude mice showed a decrease in survival and higher metastasis formation when compared to the mock cells. Conclusion: In summary, the overexpression of ST3Gal III in these pancreatic adenocarcinoma cell lines underlines the rol
- …