Adaptive Noise Reduction Algorithm to Improve R Peak Detection in ECG Measured by Capacitive ECG Sensors

Electrocardiograms (ECGs) can be conveniently obtained using capacitive ECG sensors. However, motion noise in measured ECGs can degrade R peak detection. To reduce noise, properties of reference signal and ECG measured by the sensors are analyzed and a new method of active noise cancellation (ANC) is proposed in this study. In the proposed algorithm, the original ECG signal at QRS interval is regarded as impulsive noise because the adaptive filter updates its weight as if impulsive noise is added. As the proposed algorithm does not affect impulsive noise, the original signal is not reduced during ANC. Therefore, the proposed algorithm can conserve the power of the original signal within the QRS interval and reduce only the power of noise at other intervals. The proposed algorithm was verified through comparisons with recent research using data from both indoor and outdoor experiments. The proposed algorithm will benefit a noise reduction of noisy biomedical signal measured from sensors.11Ysciescopu

Temperature-dependent evolutions of excitonic superfluid plasma frequency in a srong excitonic insulator candidate, Ta2_2NiSe5_5

We investigate an interesting anisotropic van der Waals material, Ta$_{2}$NiSe$_{5}$, using optical spectroscopy. Ta$_{2}$NiSe$_{5}$ has been known as one of the few excitonic insulators proposed over 50 years ago. Ta$_{2}$NiSe$_{5}$ has quasi-one dimensional chains along the $a$-axis. We have obtained anisotropic optical properties of a single crystal Ta$_{2}$NiSe$_{5}$ along the $a$- and $c$-axes. The measured $a$- and $c$-axis optical conductivities exhibit large anisotropic electronic and phononic properties. With regard to the $a$-axis optical conductivity, a sharp peak near 3050 cm$^{-1}$ at 9 K, with a well-defined optical gap ($\Delta^{EI} \simeq$ 1800 cm$^{-1}$) and a strong temperature-dependence, is observed. With an increase in temperature, this peak broadens and the optical energy gap closes around $\sim$325 K($T_c^{EI}$). The spectral weight redistribution with respect to the frequency and temperature indicates that the normalized optical energy gap ($\Delta^{EI}(T)/\Delta^{EI}(0)$) is $1-(T/T_c^{EI})^2$. The temperature-dependent superfluid plasma frequency of the excitonic condensation in Ta$_{2}$NiSe$_{5}$ has been determined from measured optical data. Our findings may be useful for future research on excitonic insulators.Comment: 17 pages, 5 figure

OASIS: Online Application for the Survival Analysis of Lifespan Assays Performed in Aging Research

Aging is a fundamental biological process. Characterization of genetic and environmental factors that influence lifespan is a crucial step toward understanding the mechanisms of aging at the organism level. To capture the different effects of genetic and environmental factors on lifespan, appropriate statistical analyses are needed.We developed an online application for survival analysis (OASIS) that helps conduct various novel statistical tasks involved in analyzing survival data in a user-friendly manner. OASIS provides standard survival analysis results including Kaplan-Meier estimates and mean/median survival time by taking censored survival data. OASIS also provides various statistical tests including comparison of mean survival time, overall survival curve, and survival rate at specific time point. To visualize survival data, OASIS generates survival and log cumulative hazard plots that enable researchers to easily interpret their experimental results. Furthermore, we provide statistical methods that can analyze variances among survival datasets. In addition, users can analyze proportional effects of risk factors on survival.OASIS provides a platform that is essential to facilitate efficient statistical analyses of survival data in the field of aging research. Web application and a detailed description of algorithms are accessible from http://sbi.postech.ac.kr/oasis

Effectiveness of limited airway ultrasound education for medical students: a pilot study

Objective The point-of-care ultrasound of the airway (POCUS-A) is a useful examination method but there are currently no educational programs for medical students regarding it. We designed a POCUS-A training curriculum for medical students to improve three cognitive and psychomotor learning domains: knowledge of POCUS-A, image acquisition, and image interpretation. Methods Two hours of training were provided to 52 medical students in their emergency medicine (EM) rotation. Students were evaluated for cognitive and psychomotor skills before and immediately after the training. The validity measures were established with the help of six specialists and eight EM residents. A survey was administered following the curriculum. Results Cognitive skill significantly improved after the training (38.7±12.4 vs. 91.2±7.7) and there was no significant difference between medical students and EM residents in posttest scores (91.2±7.7 vs. 90.8±4.6). The success rate of overall POCUS-A performance was 95.8%. The students were confident to perform POCUS-A on an actual patient and strongly agreed to incorporate POCUS-A training in their medical school curriculum. Conclusion Cognitive and psychomotor skills of POCUS-A among medical students can be improved via a limited curriculum on EM rotation

Solubility enhancement of aggregation-prone heterologous proteins by fusion expression using stress-responsive Escherichia coli protein, RpoS

<p>Abstract</p> <p>Background</p> <p>The most efficient method for enhancing solubility of recombinant proteins appears to use the fusion expression partners. Although commercial fusion partners including maltose binding protein and glutathione-<it>S</it>-transferase have shown good performance in enhancing the solubility, they cannot be used for the proprietory production of commercially value-added proteins and likely cannot serve as universal helpers to solve all protein solubility and folding issues. Thus, novel fusion partners will continue to be developed through systematic investigations including proteome mining presented in this study.</p> <p>Results</p> <p>We analyzed the <it>Escherichia coli </it>proteome response to the exogenous stress of guanidine hydrochloride using 2-dimensional gel electrophoresis and found that RpoS (RNA polymerase sigma factor) was significantly stress responsive. While under the stress condition the total number of soluble proteins decreased by about 7 %, but a 6-fold increase in the level of RpoS was observed, indicating that RpoS is a stress-induced protein. As an N-terminus fusion expression partner, RpoS increased significantly the solubility of many aggregation-prone heterologous proteins in <it>E. coli </it>cytoplasm, indicating that RpoS is a very effective solubility enhancer for the synthesis of many recombinant proteins. RpoS was also well suited for the production of a biologically active fusion mutant of <it>Pseudomonas putida </it>cutinase.</p> <p>Conclusion</p> <p>RpoS is highly effective as a strong solubility enhancer for aggregation-prone heterologous proteins when it is used as a fusion expression partner in an <it>E. coli </it>expression system. The results of these findings may, therefore, be useful in the production of other biologically active industrial enzymes, as successfully demonstrated by cutinase.</p

The Effect of Calcipotriol on the Expression of Human β Defensin-2 and LL-37 in Cultured Human Keratinocytes

Background. Vitamin D has been reported to regulate innate immunity by controlling the expression of antimicrobial peptides (AMPs). Objective. We investigated the effect of calcipotriol on the expression of AMPs in human cultured keratinocytes. Methods. Keratinocytes were treated with lipopolysaccharide (LPS), TNF-α, Calcipotriol and irradiated with UVB, cultured, and harvested. To assess the expression of human beta defensin-2 and LL-37 in the control group, not exposed to any stimulants, the experimental group was treated with LPS, TNF-α, or UVB, and another group was treated again with calcipotriol; reverse transcriptase-polymerase chain reaction, Western blotting, and immunohistochemical staining were performed. Results. In the experimental group treated with LPS, UVB irradiation, and TNF-α, the expression of β-defensin and LL-37 was increased more than in the control group and then decreased in the experimental group treated with calcipotriol. Conclusions. Calcipotriol suppressed HBD-2 and LL-37, which were stimulated by UVB, LPS, and TNF-α

Efekti korišćenja astaksantina u ishrani na rast, pigmentaciju mišića i antioksidantne aktivnosti mlađi kalifornijske pastrmke (oncorhynchus mykiss)

This study was designed to test the effects of dietary astaxanthin on growth, muscle pigmentation, antioxidant activity and biochemical composition of juvenile rainbow trout (Oncorhynchus mykiss). Experimental diets were formulated to contain 50, 75 and 100 ppm astaxanthin (designed as AS50, AS75 and AS100). The diet without supplementation of astaxanthin was considered as the control diet. Each experimental diet was fed to three replicate groups of fish (18.5 g/fish) to visual satiation two times a day for 10 weeks. Growth performance and proximate composition of muscle of fish were not affected by dietary AS levels (P> 0.05). Total carotenoid concentration in the muscle of fish fed the AS50 diet was higher than that of fish fed the control diet, but no different to that of fish fed the AS75 and AS100 diets. The astaxanthin concentration in the muscle of fish fed AS50, AS75 and AS100 diets were higher than that of control diet. The redness (a*) of the muscle of fish fed AS50, AS75 and AS100 diets were higher than that of fish fed the control diet (P 0.05) nije uticao na performansu rasta i hemijski sastav mišića ribe. Ukupna koncentracija karotenoida u mišiću ribe koja je hranjena AS50 hranom bila je viša nego kod riba hranjenih kontrolnom hranom, ali nije bila drugačija od riba hranjenih AS75 i AS100 hranom. Koncentracija astaksantina u mišiću riba hranjenih AS50, AS75 i AS100 hranom bila je viša nego kod riba hranjenih kontrolnom hranom. Crvena boja (a*) mišića ribe koja je hranjena AS50, AS75 i AS100 hranom bila je jača nego kod ribe hranjene kontrolnom hranom (P< 0.05). Antioksidantna aktivnost DPPH, radikala hidroksila i alkila u plazmi i jetri riba nisu zavisili od nivoa astaksantina osim kod plazme koja je imala antioksidantnu aktivnost alkilnih radikala. Rezultati ove studije nagoveštavaju da se hrana koja sadrži 50 ppm astaksantina može koristiti da bi se poboljšala crvena boja mišične pigmentacije kod mlađi kalifornijske pastrmke