Effect of low intensity white light irradiation on the retinas of mice

AIM: To investigate the effect of low intensity white light irradiation on the retinas of mice.<p>METHODS: Thirty C57BL/6J mice were randomly divided into two groups. The number of the mice in each group was 15. The mice in experimental group received dark adaptation from 5:00p.m. to 6:00p.m.,and then exposed to LED white light from 6:00p.m. to 7:00p.m. everyday for a month. At 1, 3, 7, 14 and 30d after the beginning, we examed the histology of mice retinas, calculated the thickness of outer nuclear layer(ONL),inner nuclear layer(INL)and analyzed electrophysiology of mice.<p>RESULTS:One month after experiment, compared to the control group, the latency of Rod-R a wave of the mice in experimental group significantly prolonged, the amplitude of Cone-R b wave of the mice in experimental group significantly decreased and the latency of b wave of the mice in experimental group significantly prolonged(<i>P</i><0.05).There are no significant difference in the histology of retina, ONL and INL thicknesses.<p>CONCLUSION: 100lux low intensity white light could give rise to the impairment of the retinal functions in dark-adapted mice

Work Environment and Psychosocial Factors Affecting Physical Activity among Taiwanese Information Technology Professionals.

Information technology (IT) professionals are typically sedentary and little is known about factors that influence their physical activity. Research has been limited by a lack of validated measures of workplace physical activity environments. PURPOSES: The purposes of this study were to (a) examine psychometric properties of a newly translated instrument for measuring workplace environments and (b) examine relationships among work environment (supportive workplace environments and job strain), psychosocial factors (outcome expectations and self-efficacy for physical activity), and physical activity in Taiwanese IT professionals. METHODS: This research was guided by a hypothesized model using Social Cognitive Theory, incorporating variables from the demand/control model. This was a cross-sectional survey of 576 IT professionals (467 men and 109 women; M = 33.7 years, SD = 6.08) from three IT companies in Taiwan. Three instruments were translated into Chinese using a modified committee approach. Participants completed a Chinese questionnaire that included the International Physical Activity Questionnaire-Taiwan long form, Perceived Workplace Environment Scale (PWES-C), Psychological Job Demands and Job Control Scale, Scale of Exercise Self-Efficacy, Positive and Negative Outcome Expectations Scale (PNOES-C), and Historical Physical Activity Questionnaire (HPAQ-C). Structural equation modeling (SEM) was used to test the model. RESULTS: Psychometric properties of the PWES-C demonstrated satisfactory internal consistency reliability, content and construct validity. SEM analyses showed that (a) higher levels of physical activity were associated with higher perceptions of supportive workplace environments, positive outcome expectations, and self-efficacy; (b) self-efficacy partially mediated the effects of supportive workplace environments on physical activity; (c) job strain had an indirect effect on physical activity through self-efficacy; (d) the final model accounted for 31% of the variance in physical activity; and (e) the effect of gender on our findings was not substantial in multigroup analyses. CONCLUSIONS: The PWES-C is a reliable and valid measure of perceived workplace environment in Taiwanese IT professionals. Both work environment and psychosocial factors are important. Interventions directed toward increasing individuals’ confidence in their ability to overcome barriers to physical activity and positive expected outcomes of physical activity in the context of supportive workplace environments may be useful. Study limitations, implications and future directions are discussed.Ph.D.NursingUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/86354/1/yunping_1.pd

Fucoxanthin Enhances Cisplatin-Induced Cytotoxicity via NFκB-Mediated Pathway and Downregulates DNA Repair Gene Expression in Human Hepatoma HepG2 Cells

Cisplain, a platinum-containing anticancer drug, has been shown to enhance DNA repair and to inhibit cell apoptosis, leading to drug resistance. Thus, the combination of anticancer drugs with nutritional factors is a potential strategy for improving the efficacy of cisplatin chemotherapy. In this study, we investigated the anti-proliferative effects of a combination of fucoxanthin, the major non-provitamin A carotenoid found in Undaria Pinnatifida, and cisplatin in human hepatoma HepG2 cells. We found that fucoxanthin (1–10 μΜ) pretreatment for 24 h followed by cisplatin (10 μΜ) for 24 h significantly decreased cell proliferation, as compared with cisplatin treatment alone. Mechanistically, we showed that fucoxanthin attenuated cisplatin-induced NFκB expression and enhanced the NFκB-regulated Bax/Bcl-2 mRNA ratio. Cisplatin alone induced mRNA expression of excision repair cross complementation 1 (ERCC1) and thymidine phosphorylase (TP) through phosphorylation of ERK, p38 and PI3K/AKT pathways. However, fucoxanthin pretreatment significantly attenuated cisplatin-induced ERCC1 and TP mRNA expression, leading to improvement of chemotherapeutic efficacy of cisplatin. The results suggest that a combined treatment with fucoxanthin and cisplatin could lead to a potentially important new therapeutic strategy against human hepatoma cells

Chern dartboard insulator: sub-Brillouin zone topology and skyrmion multipoles

Topology plays a crucial role in many physical systems, leading to interesting states at the surface. The paradigmatic example is the Chern number defined in the Brillouin zone that leads to the robust gapless edge states. Here we introduce the reduced Chern number, defined in subregions of the Brillouin zone (BZ), and construct a family of Chern dartboard insulators (CDIs) with quantized reduced Chern numbers in the sub-BZ (sBZ) but with trivial bulk topology. CDIs are protected by mirror symmetries and exhibit distinct pseudospin textures, including (anti)skyrmions, inside the sBZ. These CDIs host exotic gapless edge states, such as M\"{o}bius fermions and midgap corner states, and can be realized in photonic crystals. Our work opens up new possibilities for exploring sBZ topology and nontrivial surface responses in topological systems

Determining the physical conditions of extremely young Class 0 circumbinary disk around VLA1623A

We present detailed analysis of high-resolution C18O (2-1), SO (88-77), CO (3-2) and DCO+ (3-2) data obtained by the Atacama Large Millimeter/sub-millimeter Array (ALMA) towards a Class 0 Keplerian circumbinary disk around VLA1623A, which represents one of the most complete analysis towards a Class 0 source. From the dendrogram analysis, we identified several accretion flows feeding the circumbinary disk in a highly anisotropic manner. Stream-like SO emission around the circumbinary disk reveals the complicated shocks caused by the interactions between the disk, accretion flows and outflows. A wall-like structure is discovered south of VLA1623B. The discovery of two outflow cavity walls at the same position traveling at different velocities suggests the two outflows from both VLA1623A and VLA1623B overlays on top of each other in the plane of sky. Our detailed flat and flared disk modeling shows that Cycle 2 C18O J = 2-1 data is inconsistent with the combined binary mass of 0.2 Msun as suggested by early Cycle 0 studies. The combined binary mass for VLA1623A should be modified to 0.3 ~ 0.5 Msun.Comment: 26 pages, 20 figures, accepted by ApJ 2020.2.2

Proteus: Simulating the Performance of Distributed DNN Training

DNN models are becoming increasingly larger to achieve unprecedented accuracy, and the accompanying increased computation and memory requirements necessitate the employment of massive clusters and elaborate parallelization strategies to accelerate DNN training. In order to better optimize the performance and analyze the cost, it is indispensable to model the training throughput of distributed DNN training. However, complex parallelization strategies and the resulting complex runtime behaviors make it challenging to construct an accurate performance model. In this paper, we present Proteus, the first standalone simulator to model the performance of complex parallelization strategies through simulation execution. Proteus first models complex parallelization strategies with a unified representation named Strategy Tree. Then, it compiles the strategy tree into a distributed execution graph and simulates the complex runtime behaviors, comp-comm overlap and bandwidth sharing, with a Hierarchical Topo-Aware Executor (HTAE). We finally evaluate Proteus across a wide variety of DNNs on three hardware configurations. Experimental results show that Proteus achieves $3.0\%$ average prediction error and preserves order for training throughput of various parallelization strategies. Compared to state-of-the-art approaches, Proteus reduces prediction error by up to $133.8\%$

In-Vitro Study on the Antibacterial and Antioxidant Activity of Four Commercial Essential Oils and In-Situ Evaluation of Their Effect on Quality Deterioration of Pacific White Shrimp (Litopenaeus vannamei) during Cold Storage

The antioxidant and antibacterial properties of four essential oils (oregano essential oil (OEO), tea tree essential oil (TTEO), wild orange essential oil (WOEO), and clove leaf essential oil (CLEO)) were determined. The in-vitro experiment indicated that CLEO had the highest total phenolic content and DPPH scavenging activity, and OEO displayed the highest antibacterial effect, so they were applied to maintain the quality of shrimp for further study. In-situ study, the total viable counts of shrimp were inhibited from 9.05 log CFU/g to 8.18 and 8.34 log CFU/g by 2% of OEO and CLEO treated alone on 10 d. The melanosis ratio was also retarded from 38.16% to 28.98% and 26.35% by the two essential oils. The inhibitory effects of OEO and CLEO on the increase of PPO activity, weight loss, and TCA-soluble peptides, and the decreasing tendency of whiteness, the contents of myofibrillar and sarcoplasmic proteins were also founded. The samples treated with 1% OEO + 1% CLEO had better quality than those treated alone. Therefore, the combination of OEO and CLEO had a synergistic effect, which displayed the highest efficiency to prevent the melanosis, bacterial growth, and protein hydrolysis of shrimp.Peer reviewe

Sesquiterpenes from the marine red alga Laurencia composita.

Four new chamigrane derivatives, laurecomin A (1). laurecomin B (2), laurecomin C (3), and laurecomin D (4), one new naturally occurring sesquiterpene, 2,10-dibromo-3-chloro-7-chamigren-9-ol acetate (5), and three known halogenated structures, deoxyprepacifenol (6), 1-bromoselin-4(14),11-diene (7), and 9-bromoselin-4(14).11-diene (8), were isolated from the marine red alga Laurencia cornposita collected from Pingtan Island, China. The structures of these compounds were unambiguously established by 1D, 2D NMR and mass spectroscopic techniques. The bioassay results showed that 2 was active against both brine shrimp and fungus Colletotrichum lagenarium. (C) 2012 Elsevier B.V. All rights reserved.Four new chamigrane derivatives, laurecomin A (1). laurecomin B (2), laurecomin C (3), and laurecomin D (4), one new naturally occurring sesquiterpene, 2,10-dibromo-3-chloro-7-chamigren-9-ol acetate (5), and three known halogenated structures, deoxyprepacifenol (6), 1-bromoselin-4(14),11-diene (7), and 9-bromoselin-4(14).11-diene (8), were isolated from the marine red alga Laurencia cornposita collected from Pingtan Island, China. The structures of these compounds were unambiguously established by 1D, 2D NMR and mass spectroscopic techniques. The bioassay results showed that 2 was active against both brine shrimp and fungus Colletotrichum lagenarium. (C) 2012 Elsevier B.V. All rights reserved