474 research outputs found
Noise Source Identification of Small Fan-BLDC Motor System for Refrigerators
Noise levels in household appliances are increasingly attracting attention from manufacturers and
customers. Legislation is becoming more severe on acceptable noise levels and low noise is a major
marketing point for many products. The latest trend in the refrigerator manufacturing industry is to use
brushless DC (BLDC) motors instead of induction motors in order to reduce energy consumption and
noise radiation. However, cogging torque from BLDC motor is an undesirable effect that prevents the
smooth rotation of the rotor and results in noise. This paper presents a practical approach for
identifying the source of excessive noise in the small fan-motor system for household refrigerators.
The source is presumed to a mechanical resonance excited by torque ripple of the BLDC motor.
By using finite element analysis, natural frequencies and mode shapes of the rotating part of the system
are obtained and they are compared with experimental mode shapes obtained by electronic torsional
excitation test which uses BLDC motor itself as an exciter.
Two experimental validations are carried out to confirm the reduction of excessive noise
Sleeve Lobectomy as an Alternative Procedure to Pneumonectomy for Non-small Cell Lung Cancer
IntroductionThe aim of this study is to compare the outcomes of sleeve lobectomy (SL) and pneumonectomy (PN) and to determine which one is more acceptable standard procedure for patients with non-small cell lung cancer.MethodsFrom 1996 to 2005, 424 patients underwent SL (n = 157) and PN (n = 267) in our institution. Propensity score matching analysis was performed to compare these two groups for mortality, morbidity, survival, recurrence, and postoperative pulmonary function.ResultsIn each group, 105 patients were eligible for analysis. The operative mortality was lower in the SL group (1.0%) than the PN group (8.6%), (p < 0.0001). The morbidity was similar (33.4% versus 29.5%, p = 0.376). The 5-year survival was lower in the PN group (PN, 32.14% versus SL, 58.43%, p = 0.0002). The recurrence pattern (locoregional versus distant) did not differ between two groups (p = 0.180). The mean actual postoperative first second forced expiratory volume in the patients underwent SL was 2.05 ± 0.55 liter, which increased by 7.9% compared with the predicted-postoperative first second forced expiratory volume.ConclusionsOur results showed that the SL can be performed with low operative risk and may offer superior survival and better postoperative pulmonary function compared with the PN in selected patients. If anatomically feasible, a SL must be considered as a favorable alternative to PN in patients with non-small cell lung cancer
Aspiration and outflow of the intermediate water in the East/Japan Sea through the Tsugaru Strait
Author Posting. © American Geophysical Union, 2008. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 35 (2008): L07601, doi:10.1029/2007GL032981.Outflow of the intermediate water in the East/Japan Sea through the Tsugaru Strait is inferred from the fact that profiling floats deployed below the sill depth in the central East/Japan Sea moved out to the Northwest Pacific Ocean through the Strait. Careful analysis of the float trajectories reveals that profiling floats parked at 350m, 700m, and 800m could be uplifted from depths below the sill of the Tsugaru Strait and moved over the 140m deep sill with a probability close to 100%. Application of an analytical model for the Bernoulli suction shows that intermediate waters can be aspirated over the sill depth of the Tsugaru Strait in late winter.This study was partly supported by the project of
ARGO for Data Assimilation project in the Meteorological Research
Institute/KMA, the Korea EAST-1(East Asian Seas Time series East
Sea) Program from the Ministry of Maritime Affairs and Fisheries, and
Korea Research Foundation Grant (KRF-2005-070-C00142). The first
author was partly supported by the Ministry of Education, Korea, through
the BK21 project
A Case of Disseminated and Fulminant Plasmacytomas That Developed during Bortezomib Treatment
Multiple myeloma is an incurable and slow growing plasma cell neoplasm. The introduction of new drugs has increased the number of treatment options. Bortezomib, the first-in-class proteasome inhibitor, has been shown to have a significant antitumor activity in the treatment of relapse/refractory patients with multiple myeloma. Additionally, plasmacytomas have shown significant response to bortezomib. In this case report, we describe a patient who developed disseminated and fulminant extramedullary plasmacytomas during combination chemotherapy treatment with bortezomib within a short period, after having shown clinical improvement
Acute Subdural Hematoma Following Spinal Cerebrospinal Fluid Drainage in a Patient with Freezing of Gait
Recommended from our members
Atrophic Gastritis: A Related Factor for Osteoporosis in Elderly Women
Purpose Osteoporosis poses a great threat to the aging society. Hypochlorhydric or achlorhydric conditions are risk factors for osteoporosis. Atrophic gastritis also decreases gastric acid production; however, the role of atrophic gastritis as a related factor for osteoporosis is unclear. We investigated the relationship between atrophic gastritis and osteoporosis in postmenopausal women over 60 years of age. Subjects and Methods A total of 401 postmenopausal women were included in this cross-sectional study, which was conducted during their medical check-ups. Bone mineral densitometry was measured using a dual energy X-ray absorptiometry. Atrophic gastritis was defined endoscopically if gastric mucosa in the antrum and the body were found to be atrophied and thinned and submucosal vessels could be well visualized. Results: The proportion of people with atrophic gastritis was higher in the osteoporotic group than in the group without osteoporosis. A linear relationship was observed in the proportion of atrophic gastritis according to the categories of normal, osteopenia, and osteoporosis at the lumbar spine (p for trend = 0.039) and femur (p for trend = 0.001). A multiple logistic regression analysis revealed that the presence of atrophic gastritis was associated with an increased odds of osteoporosis after adjusting for age, body mass index, triglyceride, high-density lipoprotein cholesterol, alcohol consumption, and smoking status (odds ratio 1.89, 95% confidence interval 1.15–3.11). Conclusions: Atrophic gastritis is associated with an increased likelihood of osteoporosis in Korean elderly women
Integrative genome-scale metabolic analysis of Vibrio vulnificus for drug targeting and discovery
Chromosome 1 of Vibrio vulnificus tends to contain larger portion of essential or housekeeping genes on the basis of the genomic analysis and gene knockout experiments performed in this study, while its chromosome 2 seems to have originated and evolved from a plasmid.The genome-scale metabolic network model of V. vulnificus was reconstructed based on databases and literature, and was used to identify 193 essential metabolites.Five essential metabolites finally selected after the filtering process are 2-amino-4-hydroxy-6-hydroxymethyl-7,8-dihydropteridine (AHHMP), D-glutamate (DGLU), 2,3-dihydrodipicolinate (DHDP), 1-deoxy-D-xylulose 5-phosphate (DX5P), and 4-aminobenzoate (PABA), which were predicted to be essential in V. vulnificus, absent in human, and are consumed by multiple reactions.Chemical analogs of the five essential metabolites were screened and a hit compound showing the minimal inhibitory concentration (MIC) of 2 μg/ml and the minimal bactericidal concentration (MBC) of 4 μg/ml against V. vulnificus was identified
In vitro activity of gemifloxacin against recent clinical isolates of bacteria in Korea.
Gemifloxacin is an enhanced-affinity fluoroquinolone with broad-spectrum antibacterial activity. In Korea, resistant bacteria are relatively more prevalent than in other industrialized countries. In this study, we studied the in vitro activities of gemifloxacin, gatifloxacin, moxifloxacin, levofloxacin, ciprofloxacin, and other commonly used antimicrobial agents against 1,689 bacterial strains isolated at four Korean university hospitals during 1999-2000. Minimum inhibitory concentrations (MICs) were determined using the agar dilution method of National Committee for Clinical Laboratory Standards. Gemifloxacin had the lowest MICs for the respiratory pathogens: 90% of Streptococcus pneumoniae, Moraxella catarrhalis, and Haemophilus influenzae were inhibited by 0.06, 0.03, and 0.03 mg/L, respectively. Gemifloxacin was more active than the other fluoroquinolones against methicillin-susceptible Staphylococcus aureus, coagulase-negative staphylococci, streptococci, and Enterococcus faecalis. The MIC90s of gemifloxacin for Klebsiella oxytoca, Proteus vulgaris, and non-typhoidal Salmonella spp. were 0.25, 1.0, and 0.12 mg/L, respectively, while those for other Gram-negative bacilli were 4-64 mg/L. In conclusion, gemifloxacin was the most active among the comparative agents against Gram-positive species, including respiratory pathogens isolated in Korea
Effects of postconditioning with N,N,N'N'-tetrakis-[2-pyridylmethyl]-ethylenediamine in isolated rat hearts
- …