88 research outputs found
Cosmology in the Einstein-Electroweak Theory and Magnetic Fields
In the SU(2)_{L} x U(1)_{Y} standard electroweak theory coupled with the
Einstein gravity, new topological configurations naturally emerge, if the
spatial section of the universe is globally a three-sphere(S^3) with a small
radius. The SU(2)_L gauge fields and Higgs fields wrap the space nontrivially,
residing at or near a local minimum of the potential. As the universe expands,
however, the shape of the potential rapidly changes and the local minimum
eventually disappears. The fields then start to roll down towards the absolute
minimum. In the absence of the U(1)_Y gauge interaction the resulting space is
a homogeneous and isotropic S^3, but the U(1)_Y gauge interaction necessarily
induces anisotropy while preserving the homogeneity of the space. Large
magnetic fields are generically produced over a substantial period of the
rolling-over transition. The magnetic field configuration is characterized by
the Hopf map.Comment: 32 pages, 16 figure
Peak-Frequency Histogram Similarity of Bowel Sounds for the Evaluation of Intestinal Conditions
Many patients worldwide suffer from constipation, which reduces their quality of life (QOL) over the long term. Carbonated water intake is expected to improve constipation by improving intestinal motility. Conversely, carbonated water intake is believed to alter bowel status via the intestinal contents (gas and liquid) and intestinal distension, and these changes may be reflected in bowel sound (BS) peak-frequency histograms. In this study, to identify changes in intestinal conditions before and after the ingestion of liquid (i.e., water/carbonated water intake), we used a novel evaluation index, namely peak-frequency histogram similarity (PFHS), which measures the changes in the peak-frequency histogram before and after liquid intake. We considered 13 subjects who participated in a liquid intake test, and PFHS values before and after carbonated water intake were found to be significantly lower than those before and after cold water intake (p < 0.01). However, when using conventional frequency-domain features, this difference was not identified. The results obtained in this study suggest that PFHS can identify changes in bowel status (including intestinal gas and distension) that could not be found using conventional BS frequency domain features. Our findings provide a novel method of research for investigators to non-invasively monitor and evaluate intestinal conditions such as the intestinal gas volume and intestinal distention, which are associated with constipation, using a BS-based approach
Automatic Bowel Motility Evaluation Technique for Noncontact Sound Recordings
Information on bowel motility can be obtained via magnetic resonance imaging (MRI)s and X-ray imaging. However, these approaches require expensive medical instruments and are unsuitable for frequent monitoring. Bowel sounds (BS) can be conveniently obtained using electronic stethoscopes and have recently been employed for the evaluation of bowel motility. More recently, our group proposed a novel method to evaluate bowel motility on the basis of BS acquired using a noncontact microphone. However, the method required manually detecting BS in the sound recordings, and manual segmentation is inconvenient and time consuming. To address this issue, herein, we propose a new method to automatically evaluate bowel motility for noncontact sound recordings. Using simulations for the sound recordings obtained from 20 human participants, we showed that the proposed method achieves an accuracy of approximately 90% in automatic bowel sound detection when acoustic feature power-normalized cepstral coefficients are used as inputs to artificial neural networks. Furthermore, we showed that bowel motility can be evaluated based on the three acoustic features in the time domain extracted by our method: BS per minute, signal-to-noise ratio, and sound-to-sound interval. The proposed method has the potential to contribute towards the development of noncontact evaluation methods for bowel motility
Auditory Property-Based Features and Artificial Neural Network Classifiers for the Automatic Detection of Low-Intensity Snoring/Breathing Episodes
The definitive diagnosis of obstructive sleep apnea syndrome (OSAS) is made using an overnight polysomnography (PSG) test. This test requires that a patient wears multiple measurement sensors during an overnight hospitalization. However, this setup imposes physical constraints and a heavy burden on the patient. Recent studies have reported on another technique for conducting OSAS screening based on snoring/breathing episodes (SBEs) extracted from recorded data acquired by a noncontact microphone. However, SBEs have a high dynamic range and are barely audible at intensities >90 dB. A method is needed to detect SBEs even in low-signal-to-noise-ratio (SNR) environments. Therefore, we developed a method for the automatic detection of low-intensity SBEs using an artificial neural network (ANN). However, when considering its practical use, this method required further improvement in terms of detection accuracy and speed. To accomplish this, we propose in this study a new method to detect low SBEs based on neural activity pattern (NAP)-based cepstral coefficients (NAPCC) and ANN classifiers. Comparison results of the leave-one-out cross-validation demonstrated that our proposed method is superior to previous methods for the classification of SBEs and non-SBEs, even in low-SNR conditions (accuracy: 85.99 ± 5.69% vs. 75.64 ± 18.8%)
Visceral fat accumulation influenced blood flow velocity in hypertensive subjects
Arterial function measurements are widely used as surrogate markers of cardiovascular disease. However, it is unknown whether non-pathological factor may influence these measurements in particularly blood velocity function. The aim of current study was to investigate the relationship between visceral fat (VF) accumulation and hypertension incidence. The study evaluated the changes of blood velocity waveforms among normotensive and hypertensive subjects. One hundred twenty six individuals were classified into three groups which are lower VF, middle VF and higher VF regarding on their VF level. Resistive index (RI), velocity reflection index (VRI) and vascular elastic recoil index (VEI) were calculated from the 3 minutes assemble average of envelope waveform. The VF accumulation was higher in hypertensive than normotensive subjects. Peak systolic (S1), peak diastolic (D), VRI and VEI modulated significantly (P < 0.05) in higher VF compared to lower VF groups. RI and VRI show significantly different in hypertensive compared to normotensive groups. In conclusion, increased VF influences hypertension incidence and blood velocity regulation
Effect of the solvent used to prepare the photoactive layer on the performance of inverted bulk heterojunction polymer solar cells
The initial performance and subsequent degradation of inverted polymer solar cells [indium-tin oxide/titanium oxide (TiOx)/[6,6]-phenyl C61 butyric acid methyl ester (PCBM): regioregular poly(3-hexylthiophene) (P3HT)/poly(3,4-ethylenedioxylenethiophene):poly(4- styrene sulfonic acid)/Au, TiOx cell] are studied by photocurrent-voltage measurements as well as ac impedance spectroscopy (IS) and carrier mobility measurements. The TiOx cells containing a P3HT:PCBM layer prepared from a solution of chlorobenzene (CB) showed a maximum power conversion efficiency (PCE) of 2.23%. In contrast, the TiOx cells containing a P3HT:PCBM layer prepared from a solution of 1,2,3,4- tetrahydronaphthalene (tetralin) containing 2 vol- 1,8-octanedithiol (ODT) exhibited a maximum PCE of 2.92%. However, after exposure to light irradiation for 100 h, the maximum PCE of the tetralin:ODT cell decreased to 68% of its initial value. On the other hand, over 96% of the maximum PCE was maintained in the CB cell after 100 h of irradiation. The IS measurement results suggest that the degradation of the Tetralin: ODT cell was caused by a morphological change of the P3HT:PCBM layer that made efficient photoinduced charge separation difficult. © 2014 The Japan Society of Applied Physics
Irradiation by a Combination of Different Peak-Wavelength Ultraviolet-Light Emitting Diodes Enhances the Inactivation of Influenza A Viruses
Influenza A viruses (IAVs) pose a serious global threat to humans and their livestock. This study aimed to determine the ideal irradiation by ultraviolet-light emitting diodes (UV-LEDs) for IAV disinfection. We irradiated the IAV H1N1 subtype with 4.8 mJ/cm2 UV using eight UV-LEDs [peak wavelengths (WL) = 365, 310, 300, 290, 280, 270, and 260 nm)] or a mercury low pressure (LP)-UV lamp (Peak WL = 254 nm). Inactivation was evaluated by the infection ratio of Madin–Darby canine kidney (MDCK) cells or chicken embryonated eggs. Irradiation by the 260 nm UV-LED showed the highest inactivation among all treatments. Because the irradiation-induced inactivation effects strongly correlated with damage to viral RNA, we calculated the correlation coefficient (RAE) between the irradiant spectrum and absorption of viral RNA. The RAE scores strongly correlated with the inactivation by the UV-LEDs and LP-UV lamp. To increase the RAE score, we combined three different peak WL UV-LEDs (hybrid UV-LED). The hybrid UV-LED (RAE = 86.3) significantly inactivated both H1N1 and H6N2 subtypes to a greater extent than 260 nm (RAE = 68.6) or 270 nm (RAE = 42.2) UV-LEDs. The RAE score is an important factor for increasing the virucidal effects of UV-LED irradiation
Identification of Genes Associated with Sensitivity to Ultraviolet A (UVA) Irradiation by Transposon Mutagenesis of Vibrio parahaemolyticus
Ultraviolet (UV) irradiation is used to disinfect water and food and can be classified as UVA (detected at wavelengths 320–400 nm), UVB (280–320 nm), and UVC (<280 nm). We developed a method for UVA sterilization of equipment with a UVA-light-emitting diode (LED); however, a high rate of fluence was needed to promote pathogen inactivation. The aim of this study was to identify genes associated with UVA sensitivity with the goal of improving UVA-LED-mediated bactericidal activity. We constructed a transposon-mutant library of Vibrio parahaemolyticus and selected six mutants with high sensitivity to UVA irradiation. Genes associated with this phenotype include F-type H+-transporting ATPases (atp), as well as those involved in general secretion (gsp), and ubiquinone and terpenoid-quinone biosynthesis (ubi). Gene complementation resulted in decreased sensitivity to UVA-LED. The atp mutants had lower intracellular adenosine triphosphate (ATP) concentrations than the wild-type treatment, with 20 mM L-serine resulting in elevated ATP concentrations and decreased sensitivity to UVA-LED. The gsp mutants exhibited high levels of extracellular protein transport and the ubi mutants exhibited significantly different intracellular concentrations of ubiquinone-8. Taken together, our results suggest that the protein products of the atp, gsp, and ubi genes may regulate sensitivity to UVA irradiation
紫外線発光ダイオード照射は宿主細胞内でのウイルスRNAの複製と転写を抑制することでA型インフルエンザウイルスを不活化する
Influenza A viruses (IAVs) pose a serious global threat to humans and their livestock, especially poultry and pigs. This study aimed to investigate how to inactivate IAVs by using different ultraviolet-light-emitting diodes (UV-LEDs). We developed sterilization equipment with light-emitting diodes (LEDs) those peak wavelengths were 365 nm (UVA-LED), 310 nm (UVB-LED), and 280 nm (UVC-LED). These UV-LED irradiations decreased dose fluence-dependent plaque-forming units of IAV H1N1 subtype (A/Puerto Rico/8/1934) infected Madin-Darby canine kidney (MDCK) cells, but the inactivation efficiency of UVA-LED was significantly lower than UVB- and UVC-LED. UV-LED irradiations did not alter hemagglutination titer, but decreased accumulation of intracellular total viral RNA in infected MDCK cells was observed. Additionally, UV-LED irradiations suppressed the accumulation of intracellular mRNA (messenger RNA), vRNA (viral RNA), and cRNA (complementary RNA), as measured by strand-specific RT-PCR. These results suggest that UV-LEDs inhibit host cell replication and transcription of viral RNA. Both UVB- and UVC-LED irradiation decreased focus-forming unit (FFU) of H5N1 subtype (A/Crow/Kyoto/53/2004), a highly pathogenic avian IAV (HPAI), in infected MDCK cells, and the amount of FFU were lower than the H1N1 subtype. From these results, it appears that IAVs may have different sensitivity among the subtypes, and UVB- and UVC-LED may be suitable for HPAI virus inactivation
青色発光ダイオードはオプシン3を介し大腸癌細胞のオートファジーを誘導する
Light emitting-diodes (LED) have various effects on living organisms and recent studies have shown the efficacy of visible light irradiation from LED for anticancer therapies. However, the mechanism of LED’s effects on cancer cells remains unclear. The aim of the present study was to investigate the effects of LED on colon cancer cell lines and the role of photoreceptor Opsin 3 (Opn3) on LED irradiation in vitro. Human colon cancer cells (HT-29 or HCT-116) were seeded onto laboratory dishes and irradiated with 465-nm LED at 30 mW/cm2 for 30 minutes. Cell Counting Kit-8 was used to measure cell viability, and apoptosis and caspase 3/8 expression were evaluated by AnnexinV/PI and reverse transcription-polymerase chain reaction (RT-PCR), respectively. Autophagy and expression of LC-3 and beclin-1 were also evaluated by autophagy assays, RT-PCR and Western blotting. We further tested Opn3 knockdown by Opn3 siRNA and the Gi/o G-protein inhibitor NF023 in these assays. Viability of HT-29 and HCT-116 cells was lower in 465-nm LED-irradiated cultures than in control cultures. LC-3 and beclin-1 expressions were significantly higher in LED-irradiated cultures, and autophagosomes were detected in irradiated cells. The reductive effect of cancer cell viability following blue LED irradiation was reversed by Opn3 knockdown or NF023 treatment. Furthermore, increased LC-3 and beclin-1 expression that resulted from blue LED irradiation was suppressed by Opn3 knockdown or NF023 treatment. Blue LED irradiation suppressed the growth of colon cancer cells and Opn3 may play an important role as a photoreceptor
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