608 research outputs found
Improving Prediction Quality in Collaborative Filtering Based on Clustering
In this paper we present the recommender systems that use the k-means clustering method in order to solve the problems associated with neighbor selection. The first method is to solve the problem in which customers belong to different clusters due to the distance-based characteristics despite the fact that they are similar customers, by properly converting data before performing clustering. The second method explains the k-prototype algorithm performing clus-tering by expanding not only the numeric data but also the categorical data. The experimental results show that better prediction quality can be obtained when both methods are used together. 1
Dual priming oligonucleotide system for the multiplex detection of respiratory viruses and SNP genotyping of CYP2C19 gene
Successful PCR starts with proper priming between an oligonucleotide primer and the template DNA. However, the inevitable risk of mismatched priming cannot be avoided in the currently used primer system, even though considerable time and effort are devoted to primer design and optimization of reaction conditions. Here, we report a novel dual priming oligonucleotide (DPO) which contains two separate priming regions joined by a polydeoxyinosine linker. The linker assumes a bubble-like structure which itself is not involved in priming, but rather delineates the boundary between the two parts of the primer. This structure results in two primer segments with distinct annealing properties: a longer 5′-segment that initiates stable priming, and a short 3′-segment that determines target-specific extension. This DPO-based system is a fundamental tool for blocking extension of non-specifically primed templates, and thereby generates consistently high PCR specificity even under less than optimal PCR conditions. The strength and utility of the DPO system are demonstrated here using multiplex PCR and SNP genotyping PCR
Geomagnetic field influences probabilistic abstract decision-making in humans
To resolve disputes or determine the order of things, people commonly use
binary choices such as tossing a coin, even though it is obscure whether the
empirical probability equals to the theoretical probability. The geomagnetic
field (GMF) is broadly applied as a sensory cue for various movements in many
organisms including humans, although our understanding is limited. Here we
reveal a GMF-modulated probabilistic abstract decision-making in humans and the
underlying mechanism, exploiting the zero-sum binary stone choice of Go game as
a proof-of-principle. The large-scale data analyses of professional Go matches
and in situ stone choice games showed that the empirical probabilities of the
stone selections were remarkably different from the theoretical probability. In
laboratory experiments, experimental probability in the decision-making was
significantly influenced by GMF conditions and specific magnetic resonance
frequency. Time series and stepwise systematic analyses pinpointed the
intentionally uncontrollable decision-making as a primary modulating target.
Notably, the continuum of GMF lines and anisotropic magnetic interplay between
players were crucial to influence the magnetic field resonance-mediated
abstract decision-making. Our findings provide unique insights into the impact
of sensing GMF in decision-makings at tipping points and the quantum mechanical
mechanism for manifesting the gap between theoretical and empirical probability
in 3-dimensional living space.Comment: 32 pages, 5 figures, 4 supplementary figures, 2 supplementary tables,
and separate 15 ancillary file
Experimental Studies on Wave Interactions of Partially Perforated Wall under Obliquely Incident Waves
This study presents wave height distribution in terms of stem wave evolution phenomena on partially perforated wall structures through three-dimensional laboratory experiments. The plain and partially perforated walls were tested to understand their effects on the stem wave evolution under the monochromatic and random wave cases with the various wave conditions, incident angle (from 10 to 40 degrees), and configurations of front and side walls. The partially perforated wall reduced the relative wave heights more effectively compared to the plain wall structure. Partially perforated walls with side walls showed a better performance in terms of wave height reduction compared to the structure without the side wall. Moreover, the relative wave heights along the wall were relatively small when the relative chamber width is large, within the range of the chamber width in this study. The wave spectra showed a frequency dependency of the wave energy dissipation. In most cases, the existence of side wall is a more important factor than the porosity of the front wall in terms of the wave height reduction even if the partially perforated wall was still effective compared to the plain wall
Nucleotide sequence of the vmhA gene encoding hemolysin from Vibrio mimicus
AbstractThe structural gene (vmhA) of hemolysin from Vibrio mimicus (ATCC33653) was cloned and sequenced. The vmhA gene contains an open reading frame consisting of 2232 nucleotides which can code for a protein of 744 amino acids with a predicted molecular mass of 83 059. The similarity of amino acid sequence shows 81.6% identity with Vibrio cholerae El Tor hemolysin
A Case of Accidental Macular Injury by Nd: YAG Laser and Subsequent 6 Year Follow-Up
Here, we report the case of a patient who sustained Nd: YAG laser macular injury with subsequent 6 year follow-up evaluation. A 23-year-old female was accidentally exposed to a Q-switched Nd: YAG laser without protective goggles. Upon initial evaluation, the best-corrected visual acuity of her affected eye was 20/100 OD. Fundoscopic examination revealed a macular laser burn and vitreous hemorrhage. Corticosteroids, in the form of 60 mg prednisolone, were administered orally with a 10 mg per week taper. Nineteen days following exposure, fundoscopic examination revealed a distinct epiretinal membrane which resolved within six months. The best-corrected visual acuity of the affected eye remained 20/100 OD. This clinical course is similar to those of previously reported cases including vitreous hemorrhage and subsequent epiretinal membrane formation. However, visual acuity did not recover despite spontaneous regression of the epiretinal membrane and at 6 year follow-up, there was neither choroidal neovascularization nor macular hole formation
Rationale of decreasing low-density lipoprotein cholesterol below 70 mg/dL in patients with coronary artery disease: A retrospective virtual histology-intravascular ultrasound study
Background: The associations between statin and coronary plaque compositional changes were reported according to the use of high dose or not. An evaluation of the impact of low-density lipoprotein cholesterol (LDL-C) < 70 mg/dL by using real world dosages of statin on coronary plaque composition was undertaken.
Methods: The study subjects consisted of 61 patients (mean 59.9 years old, 45 males) who underwent percutaneous coronary intervention, baseline and follow-up (F/U; mean 8.4 months) virtual histology- -intravascular ultrasound (VH-IVUS) examination. Change of plaque composition at peri-stent area, which was selected in order to measure the identical site at F/U study, was compared according to the F/U LDL-C level.
Results: Body mass index, prevalence of dyslipidemia, baseline total cholesterol and baseline LDL-C were significantly lower in F/U LDL-C < 70 mg/dL group (14 segments in 10 patients) than F/U LDL-C ≥ 70 mg/dL group (79 segments in 51 patients). F/U high-density lipoprotein cholesterol (HDL-C, OR 1.06, 95% CI 1.00–1.11, p = 0.054) and F/U LDL-C < 70 mg/dL (OR 3.43, 95% CI 0.97–12.17, p = 0.056) showed strong tendency of regression of necrotic core volume (NCV) ≥ 10%. In multivariable logistic regression analysis, F/U HDL-C (OR 1.07, 95% CI 1.01–1.14, p = 0.020) and F/U LDL-C < 70 mg/dL (OR 8.02, 95% CI 1.58–40.68, p = 0.012) were the independent factors for regression of NCV ≥ 10%.
Conclusions: Follow-up LDL-C level < 70 mg/dL with any types of statins and increase of HDL-C were associated with regression of NCV ≥ 10% in patients with coronary artery disease
Flavonol glycosides from the aerial parts of Aceriphyllum rossii and their antioxidant activities
The methanol extract obtained from the aerial parts ofAceriphyllum rossii (Saxifragaceae) was fractionated into ethyl acetate (EtOAc),n-BuOH and H2O layers through solvent fractionation. Repeated silica gel column chromatography of EtOAc andn-BuOH layers afforded six flavonol glycosides. They were identified as kaempferol 3-O-β-D-glucopyranoside (astragalin,1), quercetin 3-O-β-D-glucopyranoside (isoquercitrin,2), kaempferol 3-O-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside (3), quercetin 3-O-α-L-rhamnopyranosyl (1→6)-β-D-glucopyrano-side (rutin,4), kaempferol 3-O-[α-L-rhamnopyranosyl (1→4)-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside] (5) and quercetin 3-O-[α-L-rhamnopyranosyl (1→4)-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside] (6) on the basis of several spectral data. The antioxidant activity of the six compounds was investigated using two free radicals such as the ABTS free radical and superoxide anion radical. Compound1 exhibited the highest antioxidant activity in the ABTS2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging method. 100 mg/L of compound1 was equivalent to 72.1±1.4 mg/L of vitamin C, and those of compounds3 and5 were equivalent to 62.7±0.5 mg/L and 54.3±1.3 mg/L of vitamin C, respectively. And in the superoxide anion radical scavenging method, compound5 exhibited the highest activity with an IC50 value of 17.6 ± 0.3 μM. In addition, some physical and spectral data of the flavonoids were confirme
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