291 research outputs found
Dengue epidemic in southern Vietnam, 1998.
A widespread epidemic of dengue hemorrhagic fever (DHF) occurred in southern Vietnam in 1998, with 438.98 cases/100,000 population and 342 deaths. The number of DHF cases and deaths per 100,000 population increased 152.4% and 151.8%, respectively, over a 1997 epidemic. Dengue viruses were isolated from 143 patient blood samples; DEN-3 virus was identified as the predominant serotype, although a resurgence of DEN-4 was noted
Verifiably Truthful Mechanisms
It is typically expected that if a mechanism is truthful, then the agents
would, indeed, truthfully report their private information. But why would an
agent believe that the mechanism is truthful? We wish to design truthful
mechanisms, whose truthfulness can be verified efficiently (in the
computational sense). Our approach involves three steps: (i) specifying the
structure of mechanisms, (ii) constructing a verification algorithm, and (iii)
measuring the quality of verifiably truthful mechanisms. We demonstrate this
approach using a case study: approximate mechanism design without money for
facility location
A TQFT associated to the LMO invariant of three-dimensional manifolds
We construct a Topological Quantum Field Theory (in the sense of Atiyah)
associated to the universal finite-type invariant of 3-dimensional manifolds,
as a functor from the category of 3-dimensional manifolds with parametrized
boundary, satisfying some additional conditions, to an algebraic-combinatorial
category. It is built together with its truncations with respect to a natural
grading, and we prove that these TQFTs are non-degenerate and anomaly-free. The
TQFT(s) induce(s) a (series of) representation(s) of a subgroup of
the Mapping Class Group that contains the Torelli group. The N=1 truncation
produces a TQFT for the Casson-Walker-Lescop invariant.Comment: 28 pages, 13 postscript figures. Version 2 (Section 1 has been
considerably shorten, and section 3 has been slightly shorten, since they
will constitute a separate paper. Section 4, which contained only announce of
results, has been suprimated; it will appear in detail elsewhere.
Consequently some statements have been re-numbered. No mathematical changes
have been made.
Displacement experiments provide evidence for path integration in Drosophila
Like many other animals, insects are capable of returning to previously visited locations using path integration, which is a memory of travelled direction and distance. Recent studies suggest that Drosophila can also use path integration to return to a food reward. However, the existing experimental evidence for path integration in Drosophila has a potential confound: pheromones deposited at the site of reward might enable flies to find previously rewarding locations even without memory. Here, we show that pheromones can indeed cause naïve flies to accumulate where previous flies had been rewarded in a navigation task. Therefore, we designed an experiment to determine if flies can use path integration memory despite potential pheromonal cues by displacing the flies shortly after an optogenetic reward. We found that rewarded flies returned to the location predicted by a memory-based model. Several analyses are consistent with path integration as the mechanism by which flies returned to the reward. We conclude that although pheromones are often important in fly navigation and must be carefully controlled for in future experiments, Drosophila may indeed be capable of performing path integration
Statistical Analsysis to Evaluate Heavy Metal Pollution in the Air Obatained by Moss Technique in Hanoi and its Surrounding Region
The aim of this paper was the application of statistical analysis including principal component analysis to evaluate heavy metal pollution obtained by moss technique in the air of Ha Noi and its surrounding areas and to evaluate potential pollution sources. The concentrations of 33 heavy metal elements in 27 samples of Barbula Indica moss in the investigated region collected in December of 2016 in the investigated area have been examined using multivariate statistical analysis. Five factors explaining 80% of the total variance were identified and their potential sources have been discussed
Gynostemma pentaphyllum
Aims. To evaluate the effect of the traditional Vietnamese herb Gynostemma pentaphyllum tea on insulin sensitivity in drug-naïve type 2 diabetic patients. Methods. Patients received GP or placebo tea 6 g daily for four weeks and vice versa with a 2-week wash-out period. At the end of each period, a somatostatin-insulin-glucose infusion test (SIGIT) was performed to evaluate the insulin sensitivity. Fasting plasma glucose (FPG), HbA1C, and oral glucose tolerance tests and insulin levels were measured before, during, and after the treatment. Results. FPG and steady-state plasma glucose (SIGIT mean) were lower after GP treatment compared to placebo treatment (P<0.001). The levels of FPG in the control group were slightly reduced to 0.2±1.5 versus 1.9±1.0 mmol/L in GP group (P<0.001), and the effect on FPG was reversed after exchanging treatments. The glycometabolic improvements were achieved without any major change of circulating insulin levels. There were no changes in lipids, body measurements, blood pressure, and no reported hypoglycemias or acute adverse effects regarding kidney and liver parameters. Conclusion. The results of this study suggested that the GP tea exerted antidiabetic effect by improving insulin sensitivity
Class based Influence Functions for Error Detection
Influence functions (IFs) are a powerful tool for detecting anomalous
examples in large scale datasets. However, they are unstable when applied to
deep networks. In this paper, we provide an explanation for the instability of
IFs and develop a solution to this problem. We show that IFs are unreliable
when the two data points belong to two different classes. Our solution
leverages class information to improve the stability of IFs. Extensive
experiments show that our modification significantly improves the performance
and stability of IFs while incurring no additional computational cost.Comment: Thang Nguyen-Duc, Hoang Thanh-Tung, and Quan Hung Tran are co-first
authors of this paper. 12 pages, 12 figures. Accepted to ACL 202
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