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An adaptive calibration method for distributed temperature sensor is proposed to eliminate the influence of fiber attenuation and APD dark current fluctuation. The two ends of one fiber are connected to the different measuring channels of the system. In a measurement period, two measuring channel alternately inject pulse signal into optical fiber. With the help of the measured data obtained from the two channels, the attenuation function part in demodulation formula which is a function related to the distance is converted to a constant. The mean filtering method is used to restrain the influence of APD output fluctuation on the measurement results. The experiment shows that compared with the traditional adaptive demodulation method, the temperature measurement curve is smoother and the error is reduced from about 1 °C to less than 0.5 °C. [ABSTRACT FROM AUTHOR]

[Display omitted] • Preliminary analysis of chemical composition of sporoderm-broken Ganoderma lucidum spore water extract (BGLWE). • BGLWE had great antioxidant activities and hypoglycemic activities. • BGLWE attenuated CCl 4 -induced liver injury. • BGLWE could be used as a raw material for hypoglycemic and hepatoprotective functional foods. This study determined the chemical composition, antioxidant activity, hypoglycemic activity, and acute liver injury-protective effects of sporoderm-broken Ganoderma lucidum spore water extract (BGLWE). A total of 549 substances were identified in BGLWE, among which, the top three identified substances were nicotinamide (9.75 %), gamma-aminobutyric acid (9.44 %), and phytosphingosine (8.36 %). BGLWE exhibited pronounced scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), and hydroxyl radicals (IC 50 of 0.2456, 0.3637, and 3.573 mg/mL, respectively) and also possessed high ferric ion reducing power (absorbance from 0.22 to 3.06). BGLWE showed good inhibitory activities against α-amylase and α-glucosidase (IC 50 of 4.87 and 5.06 mg/mL). In animal experiments, compared with the control CCl 4 group, the enzymatic activities of glutathione peroxidase and superoxide dismutase of BGLWE were increased by 51.52 % and 41.79 %, respectively, while the malondialdehyde content was decreased by 53.99 %. These results support the use of BGLWE as a natural hypoglycemic and hepatoprotective agent that has potential applications in food and medicine. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To evaluate the effect of vitrification of mouse oocytes on the behavior of adult offspring. Study design: Oocytes from mice were vitrified, warmed and inseminated, and two-cell embryos were transferred to foster mothers. The behavioral characterization of the offspring was detected by the Morris water maze test, forced swimming test, and elevated plus maze test, and compared to that of offspring from fresh oocytes. Results: Offspring produced by vitrified oocytes showed normal motor function. In the Morris water maze test of spatial learning there was a slightly decreased time spent in the quadrant containing the platform relative to mice from fresh oocytes, but the difference did not reach statistical significance. In addition, offspring from vitrified oocytes did not exhibit alterations in emotional behavior. Conclusion: No alterations were found in the behavioral characterization of adult offspring from vitrified oocytes compared with those from fresh oocytes. [Copyright &y& Elsevier]

The fatty acid profile of Nostoc flagelliforme (strains FACHB838 and CCAP1453/33), an edible terrestrial cyanobacterium, at different temperatures (i.e., 15, 20, 25 and 30 °C) and developmental stages (hormogonia, filaments, seriate and aseriate) in liquid suspension culture was investigated. The cyanobacterial species could be classified as Type IIB according to the existing taxonomic system based on fatty acid profiling, due to the presence of C18:3 and the absence of C16:2 and C16:3 fatty acids. Within the temperature range investigated, the content of C18:3n3 increased at the expense of C18:2n3 as temperature decreased, while the fatty acid suites remained unchanged. The degree of fatty acid unsaturation also increased with decreasing temperature, with the highest being 1.28 and 1.37 at 15 °C for the strains FACHB838 and CCAP1453/33, respectively. With respect to the effect of developmental stages, there was a slight variation in fatty acids composition and contents in the two strains without changing the fatty acid suite. At the aseriate stage at 25 °C, the highest C18 fatty acid proportion amounted to 63.17 and 65.08% and the degree of fatty acid unsaturation peaked at 1.32 and 1.31 in the strains FACHB838 and CCAP1453/33, respectively, indicating more long chain unsaturated fatty acids were accumulated at this stage. [Copyright &y& Elsevier]

In the central nervous system (CNS), adenosine is an important neuromodulator and regulates neuronal and non-neuronal cellular function (e.g. microglia) by actions on extracellular adenosine A1, A2A, A2B and A3 receptors. Extracellular levels of adenosine are regulated by synthesis, metabolism, release and uptake of adenosine. Adenosine also regulates pain transmission in the spinal cord and in the periphery, and a number of agents can alter the extracellular availability of adenosine and subsequently modulate pain transmission, particularly by activation of adenosine A1 receptors. The use of capsaicin (which activates receptors selectively expressed on C-fibre afferent neurons and produces neurotoxic actions in certain paradigms) allows for an interpretation of C-fibre involvement in such processes. In the spinal cord, adenosine availability/release is enhanced by depolarization (K+, capsaicin, substance P, N-methyl-d-aspartate (NMDA)), by inhibition of metabolism or uptake (inhibitors of adenosine kinase (AK), adenosine deaminase (AD), equilibrative transporters), and by receptor-operated mechanisms (opioids, 5-hydroxytryptamine (5-HT), noradrenaline (NA)). Some of these agents release adenosine via an equilibrative transporter indicating production of adenosine inside the cell (K+, morphine), while others release nucleotide which is converted extracellularly to adenosine by ecto-5′-nucleotidase (capsaicin, 5-HT). Release can be capsaicin-sensitive, Ca2+-dependent and involve G-proteins, and this suggests that within C-fibres, Ca2+-dependent intracellular processes regulate production and release of adenosine. In the periphery, adenosine is released from both neuronal and non-neuronal sources. Neuronal release from capsaicin-sensitive afferents is induced by glutamate and by neurogenic inflammation (capsaicin, low concentration of formalin), while that from sympathetic postganglionic neurons (probably as adenosine 5′-triphosphate (ATP) with NA) occurs following more generalized inflammation. Such release is modified differentially by inhibitors of AK and AD. Following nerve injury, there is an alteration in capsaicin-sensitive adenosine release, as spinal release now is less responsive to opioids, while peripheral release is less responsive to inhibitors of metabolism. Following inflammation, adenosine is released from a variety of cell types in addition to neurons (e.g. endothelial cells, neutrophils, mast cells, fibroblasts). ATP is released both spinally and peripherally following inflammation or injury, and may be converted to adenosine by ecto-5′-nucleotidase contributing an additional source of adenosine. Release of adenosine from both spinal and peripheral compartments has inhibitory effects on pain transmission, as methylxanthine adenosine receptor antagonists reduce analgesia produced by agents which augment extracellular levels of adenosine spinally (morphine, 5-HT, substance P, AK inhibitors) and peripherally (AK inhibitors, AD inhibitors). Increases in extracellular adenosine availability also may contribute to antiinflammatory effects of certain agents (methotrexate, sulfasalazine, salicylates, AK inhibitors), and this could have secondary effects on pain signalling in chronic inflammation. The purpose of the present review is to consider: (a) the factors that regulate the extracellular availability of adenosine in the spinal cord and at peripheral sites; and (b) the extent to which this adenosine affects pain signalling in these two distinct compartments. [Copyright &y& Elsevier]

The trophic transfer of metals along the food chain has been recognized as an important issue in the study of water quality in recent years. Feeding experiments were conducted to examine the assimilation of three metals (Cd, Cr and Zn) by the zebrafish Danio reiro feeding on the freshwater zooplankton Daphnia magna. The zooplankton were exposed to radiotracers from both the aqueous and dietary phases for different duration, and then pulse-fed to the zebrafish for measurements of metal assimilation efficiency (AE). The calculated AEs were 3–8% for Cd, 2–39% for Cr, and 17–36% for Zn in the zebrafish. For Cd and Zn, there was no statistically significant difference between the two different radiolabeling routes (aqueous and dietary exposure). For Cr, the AEs were higher when it was accumulated by D. magna from the dietary source than when it was accumulated from the aqueous phase. The gut passage time (GPT) was 6–10 h for all metals, with less variation for Zn among the different treatments. There was no obvious relationship between metal GPT and metal AE, presumably due to the narrow range of variation of metal gut passage. About 5–36%, 20–31%, and 8–30% of the total Cd, Cr and Zn was found in the soft tissue of D. magna after the radiolabeling. A much higher fraction of Cd and Zn was found in the soft tissue of D. magna when the metals were accumulated from the dietary phase. No significant relationship between the metal AE and the metal distribution in the soft tissue of D. magna was however documented in this study. Our results demonstrated that there was major difference in metal AE in freshwater fish among different metals. Metal localization in prey organisms and GPT appear to have little influence on metal assimilation by the zebrafish. [Copyright &y& Elsevier]

An improved THREE-Stage Extended Kalman Filter (3S-EKF) is presented in this paper for slow target tracking by collecting azimuth and elevation angle measurements on a single platform. The 3S-EKF is derived by measurement decouple and accurate prediction of relative height. Since the one-stage extended Kalman filter has measurement coupling issues, a TWO-Stage Extended Kalman Filter (2S-EKF) is proposed. It first estimates the 2D-projected target position using the azimuth angle only followed by updating relative height using elevation measurements. However, 2S-EKF ignores the geometrical relationship between the 2D-projected target position and relative altitude, making the prediction of relative height inaccurate. Thus, the 3S-EKF algorithm is proposed in this paper based on the exploration of the geometrical constraint to improve the prediction accuracy of relative height. The proposed 3S-EKF algorithm can achieve the Bayesian Cramér-Rao lower bound. Furthermore, the theoretical bias is analyzed with various target speeds. Simulation results demonstrate that the 3S-EKF algorithm has better estimation accuracy. [ABSTRACT FROM AUTHOR]

Objective We analyzed a case of medulloblastoma with atypical dynamic imaging changes retrospectively to summarize the atypical magnetic resonance imaging (MRI) features of medulloblastoma by reviewing the literature. Methods An atypical case of medulloblastoma in the cerebellar hemisphere confirmed by pathology was analyzed retrospectively, and the literature about it was reviewed. Results The radiologic findings of the patient were based on 3 examinations. The first examination showed that the cortex of the bilateral cerebellar hemisphere had diffuse nodular thickening, with a high signal on diffusion-weighted imaging and significant enhancement. Contrast enhancement MRI 1 year later showed the signal of cerebellar hemisphere returned to normal but revealed an enhanced nodule. A reexamination 6 months later showed an irregular mass with a high-density shadow in the cerebellar vermis on CT scan. The T2-weighted image revealed multiple degenerative cysts, and the mass had significant enhancement. Conclusion The radiologic characteristics of atypical medulloblastomas vary in adults and children. Understanding the radiologic characteristics of medulloblastomas, such as MRI features, age of onset, and location of atypical medulloblastomas, can help improve the diagnosis of medulloblastomas. [ABSTRACT FROM AUTHOR]