Sample records for zona-free parthenogentically activated
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Hsieh, Y Y; Chang, C C; Tsai, H D
2001-09-01
The zona pellucida (ZP) plays a protective role during fertilization and early embryonic development. It is related to sperm binding, the acrosome reaction, prevention of polyspermic fertilization, and holding blastomeres together before the morular stage. Zona-free oocytes are accidentally encountered. If these oocytes are healthy, they can be fertilized normally by intracytoplasmic sperm injection (ICSI). We reported on a couple with male infertility undergoing oocyte retrieval after ovarian hyperstimulation. Before the ICSI procedure, cumulus cells surrounding the oocytes were removed, which resulted in one oocyte escaping from its ZP. The zona-free oocyte was fertilized normally with ICSI and developed to the 8-cell stage. We observed that the zona-free zygote had the ability to further divide, despite its loose contact. The zona-free embryo was transferred with other zona-intact embryos, but the implantation failed. We conclude that zona-free oocytes can be rescued, fertilized with ICSI, and cultured for further transfer or cryopreservation.
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Morales, P; Llanos, M; Yovich, J L; Cummins, J M; Vigil, P
1993-01-01
Several drugs have been used to stimulate human sperm motility, including 3-deoxy-adenosine, caffeine, and pentoxifylline. Pentoxifylline is an inhibitor of the phosphodiesterase and may stimulate sperm motility by increasing the intracellular levels of cAMP. In this study we have evaluated the effect of pentoxifylline in the outcome of the sperm penetration assay into zona-free hamster oocytes. Twenty-seven semen samples, obtained for diagnostic purposes, were used. After the motile sperm were selected by the swim-up technique, the samples were divided into two aliquots. One aliquot was incubated with 1 mg ml-1 of pentoxifylline at 37 degrees C, 5% CO2 for 30 min. The control aliquot was incubated with culture medium. The samples were then washed and resuspended in fresh, pentoxifylline-free medium, at a sperm concentration of 10 x 10(6) cells ml-1. One hundred microlitres of each sperm suspension was then deposited under oil and 30-40 zona-free hamster oocytes were added. After 6 h of gamete coincubation, the percentage of penetrated oocytes and the number of decondensed sperm heads were evaluated. The percentage of acrosome-reacted sperm was evaluated using the Pisum sativum lectin. The percentage of zona-free hamster oocytes penetrated was increased after pentoxifylline-treatment. The percentage of acrosome reacted sperm and the number of decondensed sperm heads per egg were not different between the control and the pentoxifylline-treated groups. The results suggest that the beneficial effect of pentoxifylline upon the sperm cells is not mediated by stimulation of the acrosome reaction.
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Transfer of bovine demi-embryos with and without the zona pellucida.
Warfield, S J; Seidel, G E; Elsden, R P
1987-09-01
Bisected bovine embryos with or without the zona pellucida were transferred to recipients nonsurgically in five field trials. Embryos were collected from superovulated donors 6.5 to 7.5 d after estrus; only embryos of good and excellent quality were bisected. Demi-embryos were transferred either within a zona pellucida, without a zona pellucida, without a zona pellucida, or in the third and fourth trials, without a zona but embedded in 7% gelatin. Pregnancies were diagnosed at 44 to 68 d of gestation. In a preliminary trial, 9/29 zona pellucida-intact demi-embryos developed into fetuses compared with 1/10 zona pellucida-free demi-embryos (P greater than .1). The proportion of zona-free demi-embryos developing to fetuses was not significantly different from the zona-intact group in the second trial either, 24/49 and 5/19, respectively. In trial 3, the proportion of zona pellucida-free demi-embryos developing was 8/25; of zona-enclosed embryos, 29/88; and of zona-free demi-embryos embedded in gelatin, 8/22 (P greater than .1). Similarly, in the fourth trial the rate of development of zona-free demi-embryos to fetuses was 5/12, that of zona-enclosed embryos was 32/81, and that of zona-free demi-embryos embedded in gelatin was 3/12 (P greater than .1). In trial 5, survival of zona-enclosed demi-embryos to fetuses was 40/105, and of zona-free demi-embryos, 46/109 (P greater than .1). Except for trial 2, half of the demi-embryos were twinned, one to each uterine horn; twinning did not significantly affect the proportion developing to fetuses for any of the demi-embryo groups. It is concluded that placing post-compaction demi-embryos into the zona pellucida for transfer does not improve pregnancy rates significantly.
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Moro, L N; Jarazo, J; Buemo, C; Hiriart, M I; Sestelo, A; Salamone, D F
2015-10-01
The aim of this study was to evaluate three different cloning strategies in the domestic cat (Felis silvestris) and to use the most efficient to generate wild felid embryos by interspecific cloning (iSCNT) using Bengal (a hybrid formed by the cross of Felis silvestris and Prionailurus bengalensis) and tiger (Panthera tigris) donor cells. In experiment 1, zona-free (ZP-free) cloning resulted in higher fusion and expanded blastocyst rates with respect to zona included cloning techniques that involved fusion or injection of the donor cell. In experiment 2, ZP-free iSCNT and embryo aggregation (2X) were assessed. Division velocity and blastocyst rates were increased by embryo aggregation in the three species. Despite fewer tiger embryos than Bengal and cat embryos reached the blastocyst stage, Tiger 2X group increased the percentage of blastocysts with respect to Tiger 1X group (3.2% vs 12.1%, respectively). Moreover, blastocyst cell number was almost duplicated in aggregated embryos with respect to non-aggregated ones within Bengal and tiger groups (278.3 ± 61.9 vs 516.8 ± 103.6 for Bengal 1X and Bengal 2X groups, respectively; 41 vs 220 ± 60 for Tiger 1X and Tiger 2X groups, respectively). OCT4 analysis also revealed that tiger blastocysts had higher proportion of OCT4-positive cells with respect to Bengal blastocysts and cat intracytoplasmic sperm injection blastocysts. In conclusion, ZP-free cloning has improved the quality of cat embryos with respect to the other cloning techniques evaluated and was successfully applied in iSCNT complemented with embryo aggregation. © 2015 Blackwell Verlag GmbH.
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Bodri, Daniel; Kato, Ryutaro; Kondo, Masae; Hosomi, Naoko; Katsumata, Yoshinari; Kawachiya, Satoshi; Matsumoto, Tsunekazu
2015-05-01
To report time-lapse monitoring of human oocytes in which the damaged zona pellucida was removed, producing zona-free (ZF) oocytes that were cultured until the blastocyst stage in time-lapse incubators. Retrospective case series. Private infertility clinic. Infertile patients (n = 32) undergoing minimal ovarian stimulation or natural cycle IVF treatment between October 2012 and June 2014. Intracytoplasmic sperm injection (ICSI) fertilization of ZF oocytes, prolonged embryo culture in time-lapse incubators, elective vitrification, and subsequent single vitrified-thawed blastocyst transfer (SVBT). Rate of fertilization, cleavage and blastocyst development, live-birth rate per SVBT cycle. In spite of advanced maternal age (39 ± 4.2; range, 30-46 years), good fertilization (94%), cleavage (94%), and blastocyst development rates (38%) were reached after fertilization and culturing of ZF oocytes/embryos. All thawed ZF blastocysts survived, and up to this date seven SVBT transfers were performed, yielding three (43%) term live births with healthy newborns. Time-lapse imagery gives a unique insight into the dynamics of embryo development in ZF embryos. Moreover, our case series demonstrate that an oocyte with a damaged zona pellucida that has been removed could be successfully fertilized with ICSI, cultured until blastocyst stage in a time-lapse incubator and vitrified electively for subsequent use. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
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Intracellular activation of ovastacin mediates pre-fertilization hardening of the zona pellucida.
Körschgen, Hagen; Kuske, Michael; Karmilin, Konstantin; Yiallouros, Irene; Balbach, Melanie; Floehr, Julia; Wachten, Dagmar; Jahnen-Dechent, Willi; Stöcker, Walter
2017-09-01
How and where is pro-ovastacin activated and how does active ovastacin regulate zona pellucida hardening (ZPH) and successful fertilization? Ovastacin is partially active before exocytosis and pre-hardens the zona pellucida (ZP) before fertilization. The metalloproteinase ovastacin is stored in cortical granules, it cleaves zona pellucida protein 2 (ZP2) upon fertilization and thereby destroys the ZP sperm ligand and triggers ZPH. Female mice deficient in the extracellular circulating ovastacin-inhibitor fetuin-B are infertile due to pre-mature ZPH. We isolated oocytes from wild-type and ovastacin-deficient (Astlnull) FVB mice before and after fertilization (in vitro and in vivo) and quantified ovastacin activity and cleavage of ZP2 by immunoblot. We assessed ZPH by measuring ZP digestion time using α-chymotrypsin and by determining ZP2 cleavage. We determined cellular distribution of ovastacin by immunofluorescence using domain-specific ovastacin antibodies. Experiments were performed at least in triplicate with a minimum of 20 oocytes. Data were pre-analyzed using Shapiro-Wilk test. In case of normal distribution, significance was determined via two-sided Student's t-test, whereas in case of non-normal distribution via Mann-Whitney U-test. Metaphase II (MII) oocytes contained both inactive pro-ovastacin and activated ovastacin. Immunoblot and ZP digestion assays revealed a partial cleavage of ZP2 even before fertilization in wild-type mice. Partial cleavage coincided with germinal-vesicle breakdown and MII, despite the presence of fetuin-B protein, an endogenous ovastacin inhibitor, in the follicular and oviductal fluid. Upon exocytosis, part of the C-terminal domain of ovastacin remained attached to the plasmalemma, while the N-terminal active ovastacin domain was secreted. This finding may resolve previously conflicting data showing that ovastacin acts both as an oolemmal receptor termed SAS1B (sperm acrosomal SLLP1 binding protein; SLLP, sperm lysozyme like
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Jin, Mayuko; Fujiwara, Eiji; Kakiuchi, Yasutaka; Okabe, Masaru; Satouh, Yuhkoh; Baba, Shoji A.; Chiba, Kazuyoshi; Hirohashi, Noritaka
2011-01-01
To fuse with oocytes, spermatozoa of eutherian mammals must pass through extracellular coats, the cumulus cell layer, and the zona pellucida (ZP). It is generally believed that the acrosome reaction (AR) of spermatozoa, essential for zona penetration and fusion with oocytes, is triggered by sperm contact with the zona pellucida. Therefore, in most previous studies of sperm–oocyte interactions in the mouse, the cumulus has been removed before insemination to facilitate the examination of sperm–zona interactions. We used transgenic mouse spermatozoa, which enabled us to detect the onset of the acrosome reaction using fluorescence microscopy. We found that the spermatozoa that began the acrosome reaction before reaching the zona were able to penetrate the zona and fused with the oocyte's plasma membrane. In fact, most fertilizing spermatozoa underwent the acrosome reaction before reaching the zona pellucida of cumulus-enclosed oocytes, at least under the experimental conditions we used. The incidence of in vitro fertilization of cumulus-free oocytes was increased by coincubating oocytes with cumulus cells, suggesting an important role for cumulus cells and their matrix in natural fertilization. PMID:21383182
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Dang, Wei-min; Wang, Sheng; Tian, Shi-xiu; Chen, Bing; Sun, Fei; Li, Wei; Jiao, Yan; He, Li-hua
2007-02-01
To explore the biological effects of infrasound on the polygonal cells in adrenal cortex zona fasciculation in mice. The biological effects of infrasound on the activities of 3beta hydroxysteroid dehydrogenase (3-betaHSDH) and acid phosphatase(ACP) of the polygonal cells in adrenal cortex zona fasciculate were observed when exposure to 8 and 16 Hz infrasound at 80, 90, 100, 110, 120 and 130 dB for 1 day, 7 days and 14 days or 14 days after the exposure. When exposure to 8 Hz infrasound, the enzyme activities of 3-betaHSDH increase as the sound pressure levels increase. Only when the sound pressure levels reach 130 dB, the enzyme activities began to decrease exceptionally. When exposure to 16 Hz, 80 dB infrasound, no significant difference between the treatment and control group in the activities of 3-betaHSDH could be observed, but the injury of the polygonal cells had appeared. When exposure to 16 Hz, 100 dB infrasound, the activities of 3-betaHSDH started to increase. The cell injury still existed. When exposed to 16 Hz, 120 dB infrasound, the local tissue damage represented. Fourteen days after the mice exposure to 8 Hz, 90 dB and 130 dB infrasound for 14 days continuously, the local tissue injury of the adrenal cortex zona fasciculation began to recover at certain extent, but the higher the exposure sound pressure level, the poorer the tissue recovery. The biological effects of infrasound on the polygonal cells in adrenal cortex zona fasciculation response to the frequency of the infrasound are found at certain action strength range, but this characteristic usually is covered by the severe tissue injury. When exposure to infrasound is stopped for a period of time, the local tissue injury of the adrenal cortex zona fasciculation could recovers at certain extent, but the higher the exposure sound pressure level, the more poorer the tissue recovery.
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Lhx6-positive GABA-releasing neurons of the zona incerta promote sleep
Liu, Kai; Kim, Juhyun; Kim, Dong Won; Zhang, Yi Stephanie; Bao, Hechen; Denaxa, Myrto; Lim, Szu-Aun; Kim, Eileen; Liu, Chang; Wickersham, Ian R.; Pachnis, Vassilis; Hattar, Samer; Song, Juan; Brown, Solange P.; Blackshaw, Seth
2017-01-01
Multiple populations of wake-promoting neurons have been characterized in mammals, but few sleep-promoting neurons have been identified1. Wake-promoting cell types include hypocretin and GABA (γ-aminobutyric-acid)-releasing neurons of the lateral hypothalamus, which promote the transition to wakefulness from non-rapid eye movement (NREM) and rapid eye movement (REM) sleep2,3. Here we show that a subset of GABAergic neurons in the mouse ventral zona incerta, which express the LIM homeodomain factor Lhx6 and are activated by sleep pressure, both directly inhibit wake-active hypocretin and GABAergic cells in the lateral hypothalamus and receive inputs from multiple sleep–wake-regulating neurons. Conditional deletion of Lhx6 from the developing diencephalon leads to decreases in both NREM and REM sleep. Furthermore, selective activation and inhibition of Lhx6-positive neurons in the ventral zona incerta bidirectionally regulate sleep time in adult mice, in part through hypocretin-dependent mechanisms. These studies identify a GABAergic subpopulation of neurons in the ventral zona incerta that promote sleep. PMID:28847002
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De Silva, Matharage S I; Dayton, Adam W; Rhoten, Lance R; Mallett, John W; Reese, Jared C; Squires, Mathieu D; Dalley, Andrew P; Porter, James P; Judd, Allan M
2018-06-01
In bovine adrenal zona fasciculata (ZF) and NCI-H295R cells, interleukin-6 (IL-6) increases cortisol release, increases expression of steroidogenic acute regulatory protein (StAR), cholesterol side chain cleavage enzyme (P450scc), and steroidogenic factor 1 (SF-1) (increases steroidogenic proteins), and decreases the expression of adrenal hypoplasia congenita-like protein (DAX-1) (inhibits steroidogenic proteins). In contrast, IL-6 decreases bovine adrenal zona reticularis (ZR) androgen release, StAR, P450scc, and SF-1 expression, and increases DAX-1 expression. Adenosine monophosphate (AMP) activated kinase (AMPK) regulates steroidogenesis, but its role in IL-6 regulation of adrenal steroidogenesis is unknown. In the present study, an AMPK activator (AICAR) increased (P < 0.01) NCI-H295R StAR promoter activity, StAR and P450scc expression, and the phosphorylation of AMPK (PAMPK) and acetyl-CoA carboxylase (PACC) (indexes of AMPK activity). In ZR (decreased StAR, P450scc, SF-1, increased DAX-1) (P < 0.01) and ZF tissues (increased StAR, P450scc, SF-1, decreased DAX-1) (P < 0.01), AICAR modified StAR, P450scc, SF-1 and DAX-1 mRNAs/proteins similar to the effects of IL-6. The activity (increased PAMPK and PACC) (P < 0.01) of AMPK in the ZF and ZR was increased by AICAR and IL-6. In support of an AMPK role in IL-6 ZF and ZR effects, the AMPK inhibitor compound C blocked (P < 0.01) the effects of IL-6 on the expression of StAR, P450scc, SF-1, and DAX-1. Therefore, IL-6 modification of the expression of StAR and P450scc in the ZF and ZR may involve activation of AMPK and these changes may be related to changes in the expression of SF-1 and DAX-1. Copyright © 2018 Elsevier Inc. All rights reserved.
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Sperm Proteasomes Degrade Sperm Receptor on the Egg Zona Pellucida during Mammalian Fertilization
Zimmerman, Shawn W.; Manandhar, Gaurishankar; Yi, Young-Joo; Gupta, Satish K.; Sutovsky, Miriam; Odhiambo, John F.; Powell, Michael D.; Miller, David J.; Sutovsky, Peter
2011-01-01
Despite decades of research, the mechanism by which the fertilizing spermatozoon penetrates the mammalian vitelline membrane, the zona pellucida (ZP) remains one of the unexplained fundamental events of human/mammalian development. Evidence has been accumulating in support of the 26S proteasome as a candidate for echinoderm, ascidian and mammalian egg coat lysin. Monitoring ZP protein degradation by sperm during fertilization is nearly impossible because those few spermatozoa that penetrate the ZP leave behind a virtually untraceable residue of degraded proteins. We have overcome this hurdle by designing an experimentally consistent in vitro system in which live boar spermatozoa are co-incubated with ZP-proteins (ZPP) solubilized from porcine oocytes. Using this assay, mimicking sperm-egg interactions, we demonstrate that the sperm-borne proteasomes can degrade the sperm receptor protein ZPC. Upon coincubation with motile spermatozoa, the solubilized ZPP, which appear to be ubiquitinated, adhered to sperm acrosomal caps and induced acrosomal exocytosis/formation of the acrosomal shroud. The degradation of the sperm receptor protein ZPC was assessed by Western blotting band-densitometry and proteomics. A nearly identical pattern of sperm receptor degradation, evident already within the first 5 min of coincubation, was observed when the spermatozoa were replaced with the isolated, enzymatically active, sperm-derived proteasomes. ZPC degradation was blocked by proteasomal inhibitors and accelerated by ubiquitin-aldehyde(UBAL), a modified ubiquitin protein that stimulates proteasomal proteolysis. Such a degradation pattern of ZPC is consistent with in vitro fertilization studies, in which proteasomal inhibitors completely blocked fertilization, and UBAL increased fertilization and polyspermy rates. Preincubation of intact zona-enclosed ova with isolated active sperm proteasomes caused digestion, abrasions and loosening of the exposed zonae, and significantly reduced
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Ahlers, M J; Ganswindt, A; Münscher, S; Bertschinger, H J
2012-07-01
Because of overpopulation of African elephants in South Africa and the consequent threat to biodiversity, the need for a method of population control has become evident. In this regard, the potential use of the porcine zona pellucida (pZP) vaccine as an effective means for population control is explored. While potential effects of pZP treatment on social behavior of African elephants have been investigated, no examination of the influence of pZP vaccination on the endocrine correlates in treated females has been undertaken. In this study, ovarian activity of free-ranging, pZP-treated African elephant females was monitored noninvasively for 1 yr at Thornybush Private Nature Reserve, South Africa, by measuring fecal 5α-pregnan-3β-ol-20-on concentrations via enzyme immunoassay. A total of 719 fecal samples from 19 individuals were collected over the study period, averaging 38 samples collected per individual (minimum, maximum: 16, 52). Simultaneously, behavioral observations were made to record the occurrence of estrous behavior for comparison. Each elephant under study showed 5α-pregnan-3β-ol-20-on concentrations rising above baseline at some period during the study indicating luteal activity. Average 5α-pregnan-3β-ol-20-on concentrations were 1.61 ± 0.46 μg/g (mean ± SD). Within sampled females, 42.9% exhibited estrous cycles within the range reported for captive African elephants, 14.3% had irregular cycles, and 42.9% did not appear to be cycling. Average estrous cycle duration was 14.72 ± 0.85 wk. Estrous behavior coincided with the onset of the luteal phase and a subsequent rise in 5α-pregnan-3β-ol-20-on concentrations. Average 5α-pregnan-3β-ol-20-on levels positively correlated with rainfall. No association between average individual 5α-pregnan-3β-ol-20-on concentrations or cyclicity status with age or parity were detected. Earlier determination of efficacy was established via fecal hormone analysis with no pregnancies determined 22 mo post
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Beek, J; Nauwynck, H; Appeltant, R; Maes, D; Van Soom, A
2015-11-01
Serine proteases are involved in mammalian fertilization. Inhibitors of serine proteases can be applied to investigate at which point these enzymes exert their action. We selected two serine protease inhibitors, 4-(2-aminoethyl)benzenesulfonyl fluoride hydrochloride (AEBSF, 100 μM) and soybean trypsin inhibitor (STI, 5 μM) from Glycine max, via previous dose-response IVF experiments and sperm toxicity tests. In the present study, we evaluated how these inhibitors affect porcine fertilization in vitro as calculated on total fertilization rate, polyspermy rate, and the sperm number per fertilized oocyte of cumulus-intact, cumulus-free, and zona-free oocytes. In the control group (no inhibitor), these parameters were 86%, 49%, and 2.2 for cumulus-intact oocytes and 77%, 43%, and 2.2 for cumulus-free oocytes (6-hour gamete incubation period, 1.25 × 10(5) spermatozoa/mL). 4-(2-Aminoethyl)benzenesulfonyl fluoride hydrochloride and STI significantly reduced total fertilization and polyspermy rate in cumulus-intact and cumulus-free oocytes (P < 0.05). Total fertilization rates were respectively 65% and 53% (AEBSF) and 36% and 17% (STI). Inhibition rates were higher in cumulus-free oocytes than in cumulus-intact oocytes, indicating that inhibitors exerted their action after sperm passage through the cumulus. 4-(2-Aminoethyl)benzenesulfonyl fluoride hydrochloride but not STI reduced sperm binding to the ZP. The acrosome reaction was significantly inhibited by both inhibitors. Only 40.4% (AEBSF) and 11.4% (STI) of spermatozoa completed a calcium-induced acrosome reaction compared to 86.7% of spermatozoa in the control group. There was no effect on sperm binding or fertilization parameters in zona-free oocytes. In conclusion, sperm-zona binding and acrosome reaction were inhibited by serine protease inhibitors during porcine IVF. Copyright © 2015 Elsevier Inc. All rights reserved.
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Control of flexible beams using a free-free active truss
NASA Technical Reports Server (NTRS)
Clark, W. W.; Kimiavi, B.; Robertshaw, H. H.
1989-01-01
An analytical and experimental study involving controlling flexible beams using a free-free active truss is presented. This work extends previous work in controlling flexible continua with active trusses which were configured with fixed-free boundary conditions. The following describes the Lagrangian approach used to derive the equations of motion for the active truss and the beams attached to it. A partial-state feedback control law is derived for this system based on a full-state feedback Linear Quadratic Regulator method. The analytical model is examined via numerical simulations and the results are compared to a similar experimental apparatus described herein. The results show that control of a flexible continua is possible with a free-free active truss.
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Mechanics of sperm-egg interaction at the zona pellucida.
Baltz, J M; Katz, D F; Cone, R A
1988-01-01
Mammalian sperm traverse several layers of egg vestments before fertilization can occur. The innermost vestment, the zona pellucida, is a glycoprotein shell, which captures and tethers the sperm before they penetrate it. We report here direct measurements of the force required to tether a motile human sperm as well as independent calculations of this force using flagellar beat parameters observed for sperm of several species on their homologous zonae. We have compared these sperm-generated forces with the calculated tensile strength of sperm-zona bonds, and found that a motile sperm can be tethered, at least temporarily, by a single bond. Therefore, sperm can be captured by the first bond formed and tethered permanently by a few. The sperm cannot subsequently penetrate the zona unless the bonds are first eliminated. However, premature elimination would simply allow the sperm to escape. Therefore, not only must the bonds be eliminated, but the timing of this must be regulated so that the sperm is already oriented toward the egg and beginning to penetrate as the bonds are broken. Images FIGURE 6 PMID:3224150
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Zinc sparks induce physiochemical changes in the egg zona pellucida that prevent polyspermy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Que, Emily L.; Duncan, Francesca E.; Bayer, Amanda R.
During fertilization or chemically-induced egg activation, the mouse egg releases billions of zinc atoms in brief bursts known as ‘zinc sparks.’ The zona pellucida (ZP), a glycoprotein matrix surrounding the egg, is the first structure zinc ions encounter as they diffuse away from the plasma membrane. Following fertilization, the ZP undergoes changes described as ‘hardening’, which prevent multiple sperm from fertilizing the egg and thereby establish a block to polyspermy. A major event in zona hardening is cleavage of ZP2 proteins by ovastacin; however, the overall physiochemical changes contributing to zona hardening are not well understood. Using x-ray fluorescence microscopy,more » transmission and scanning electron microscopy, and biological function assays, we tested the hypothesis that zinc release contributes to ZP hardening. We found that the zinc content in the ZP increases by 300% following activation and that zinc exposure modulates the architecture of the ZP matrix. Importantly, zinc-induced structural changes of the ZP have a direct biological consequence; namely, they reduce the ability of sperm to bind to the ZP. These results provide a paradigm-shifting model in which fertilization-induced zinc sparks contribute to the polyspermy block by altering conformations of the ZP matrix. Finally, this adds a previously unrecognized factor, namely zinc, to the process of ZP hardening.« less
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Zinc sparks induce physiochemical changes in the egg zona pellucida that prevent polyspermy
Que, Emily L.; Duncan, Francesca E.; Bayer, Amanda R.; ...
2017-01-19
During fertilization or chemically-induced egg activation, the mouse egg releases billions of zinc atoms in brief bursts known as ‘zinc sparks.’ The zona pellucida (ZP), a glycoprotein matrix surrounding the egg, is the first structure zinc ions encounter as they diffuse away from the plasma membrane. Following fertilization, the ZP undergoes changes described as ‘hardening’, which prevent multiple sperm from fertilizing the egg and thereby establish a block to polyspermy. A major event in zona hardening is cleavage of ZP2 proteins by ovastacin; however, the overall physiochemical changes contributing to zona hardening are not well understood. Using x-ray fluorescence microscopy,more » transmission and scanning electron microscopy, and biological function assays, we tested the hypothesis that zinc release contributes to ZP hardening. We found that the zinc content in the ZP increases by 300% following activation and that zinc exposure modulates the architecture of the ZP matrix. Importantly, zinc-induced structural changes of the ZP have a direct biological consequence; namely, they reduce the ability of sperm to bind to the ZP. These results provide a paradigm-shifting model in which fertilization-induced zinc sparks contribute to the polyspermy block by altering conformations of the ZP matrix. Finally, this adds a previously unrecognized factor, namely zinc, to the process of ZP hardening.« less
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The anatomy of the caudal zona incerta in rodents and primates
Watson, Charles; Lind, Christopher R P; Thomas, Meghan G
2014-01-01
The caudal zona incerta is the target of a recent modification of established procedures for deep brain stimulation (DBS) for Parkinson's disease and tremor. The caudal zona incerta contains a number of neuronal populations that are distinct in terms of their cytoarchitecture, connections, and pattern of immunomarkers and is located at a position where a number of major tracts converge before turning toward their final destination in the forebrain. However, it is not clear which of the anatomical features of the region are related to its value as a target for DBS. This paper has tried to identify features that distinguish the caudal zona incerta of rodents (mouse and rat) and primates (marmoset, rhesus monkey, and human) from the remainder of the zona incerta. We studied cytoarchitecture, anatomical relationships, the pattern of immunomarkers, and gene expression in both of these areas. We found that the caudal zona incerta has a number of histological and gene expression characteristics that distinguish it from the other subdivisions of the zona incerta. Of particular note are the sparse population of GABA neurons and the small but distinctive population of calbindin neurons. We hope that a clearer appreciation of the anatomy of the region will in the end assist the interpretation of cases in which DBS is used in human patients. PMID:24138151
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Sati, Leyla; Cayli, Sevil; Delpiano, Elena; Sakkas, Denny; Huszar, Gabor
2014-05-01
In mammalian species, acquisition of sperm fertilization competence is dependent on the phenomenon of sperm capacitation. One of the key elements of capacitation is protein tyrosine phosphorylation (TP) in various sperm membrane regions. In previous studies performed, the pattern of TP was examined in human sperm bound to zona pellucida of oocytes. In the present comparative study, TP patterns upon sperm binding to the zona pellucida or hyaluronic acid (HA) were investigated in spermatozoa arising from the same semen samples. Tyrosine phosphorylation, visualized by immunofluorescence, was localized within the acrosomal cap, equatorial head region, neck, and the principal piece. Tyrosine phosphorylation has increased in a time-related manner as capacitation progressed, and the phosphorylation pattern was identical within the principal piece and neck, regardless of the sperm bound to the zona pellucida or HA. Thus, the data demonstrated that the patterns of sperm activation-related TP were similar regardless of the spermatozoa bound to zona pellucida or HA. Further, sperm with incomplete development, as detected by excess cytoplasmic retention, failed to exhibit TP.
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Sati, Leyla; Cayli, Sevil; Delpiano, Elena; Sakkas, Denny
2014-01-01
In mammalian species, acquisition of sperm fertilization competence is dependent on the phenomenon of sperm capacitation. One of the key elements of capacitation is protein tyrosine phosphorylation (TP) in various sperm membrane regions. In previous studies performed, the pattern of TP was examined in human sperm bound to zona pellucida of oocytes. In the present comparative study, TP patterns upon sperm binding to the zona pellucida or hyaluronic acid (HA) were investigated in spermatozoa arising from the same semen samples. Tyrosine phosphorylation, visualized by immunofluorescence, was localized within the acrosomal cap, equatorial head region, neck, and the principal piece. Tyrosine phosphorylation has increased in a time-related manner as capacitation progressed, and the phosphorylation pattern was identical within the principal piece and neck, regardless of the sperm bound to the zona pellucida or HA. Thus, the data demonstrated that the patterns of sperm activation-related TP were similar regardless of the spermatozoa bound to zona pellucida or HA. Further, sperm with incomplete development, as detected by excess cytoplasmic retention, failed to exhibit TP. PMID:24077441
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Morales, P; Vantman, D; Barros, C; Vigil, P
1991-03-01
Several techniques have been used for selecting motile spermatozoa including Percoll and albumin gradients, swim-up, and glass wool filtration. A high yield of motile spermatozoa as well as an enhancement of motility are the most desirable features of a practical method. An equally important consideration is whether or not these techniques select functionally normal spermatozoa. In this study we have compared two methods for separation of motile cells, swim-up and Percoll gradient. Normal semen samples from 12 different men were used in this study. Each sample was simultaneously processed by swim-up and Percoll gradient using modified Tyrode's medium. After the sperm concentration was adjusted to 1 x 10(7) spermatozoa/ml, the suspensions were incubated at 37 degrees C, 5% CO2 in air. In each suspension the percentage of sperm recovery, percentage of motile spermatozoa, percentage of acrosome reacted spermatozoa (either spontaneously or stimulated with human follicular fluid), percentage of zona-free hamster oocytes penetrated, and number of spermatozoa bound to the human zona pellucida were determined. The results obtained indicated that the percentage of sperm recovery was higher with the Percoll gradient than with the swim-up procedure (P less than 0.001). However, no significant differences were found between these two sperm populations in the percentage of motile cells, in the percentage of acrosome reacted spermatozoa, and in the percentage of zona-free hamster oocytes penetrated. In addition, the number of spermatozoa bound per zona pellucida was similar for spermatozoa selected by Percoll or swim-up. We conclude that there were no functional differences between the spermatozoa selected by either method.
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Active Free Surface Density Maps
NASA Astrophysics Data System (ADS)
Çelen, S.
2016-10-01
Percolation problems were occupied to many physical problems after their establishment in 1957 by Broadbent and Hammersley. They can be used to solve complex systems such as bone remodeling. Volume fraction method was adopted to set some algorithms in the literature. However, different rate of osteoporosis could be observed for different microstructures which have the same mass density, mechanical stimuli, hormonal stimuli and nutrition. Thus it was emphasized that the bone might have identical porosity with different specific surfaces. Active free surface density of bone refers the used total area for its effective free surface. The purpose of this manuscript is to consolidate a mathematical approach which can be called as “active free surface density maps” for different surface patterns and derive their formulations. Active free surface density ratios were calculated for different Archimedean lattice models according to Helmholtz free energy and they were compared with their site and bond percolation thresholds from the background studies to derive their potential probability for bone remodeling.
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Differences between antigenic determinants of pig and cat zona pellucida proteins.
Jewgenow, K; Rohleder, M; Wegner, I
2000-05-01
Despite many efforts, the control of reproduction in feral cat populations is still a problem in urban regions around the world. Immunocontraception is a promising approach; thus the present study examined the suitability of the widely used pig zona pellucida proteins (pZP) for contraception in feral domestic cats. Purified zona pellucida proteins obtained from pig and cat ovaries were used to produce highly specific antisera in rabbits. Antibodies against pZP raised in rabbits or lions were not effective inhibitors of either in vitro sperm binding (cat spermatozoa to cat oocytes) or in vitro fertilization in cats, whereas antibodies against feline zona pellucida proteins (fZP) raised in rabbits showed a dose-dependent inhibition of in vitro fertilization. Immunoelectrophoresis, ELISA and immunohistology of ovaries confirmed these results, showing crossreactivity of anti-fZP sera to fZP and to a lesser extent to pZP, but no interaction of anti-pZP sera with fZP. It is concluded that cat and pig zonae pellucidae express a very small number of shared antigenic determinants, making the use of pZP vaccine in cats questionable. A contraceptive vaccine based on feline zona pellucida determinants will be a better choice for the control of reproduction in feral cats if immunogenity can be achieved.
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Gupta, Neha; Shrestha, Abhinav; Panda, Amulya Kumar; Gupta, Satish Kumar
2013-07-01
Affinity tags can interfere in various physicochemical properties and immunogenicity of the recombinant proteins. In the present study, tag-free recombinant fusion protein encompassing promiscuous T cell epitope of tetanus toxoid [TT; amino acid (aa) residues 830-844] followed by dilysine linker and dog zona pellucida glycoprotein-3 (ZP3; aa residues 23-348) (TT-KK-ZP3) was expressed in Escherichia coli. The recombinant protein, expressed as inclusion bodies (IBs), was purified by isolation of IBs, processed to remove host cell proteins, followed by solubilization and refolding. A specific 39 kDa protein including ZP3 was identified by SDS-PAGE. CD spectra showed the presence of α-helices and β-sheets, and fluorescent spectroscopy revealed emission maxima of 265 A.U. at 339 nm for refolded protein and showed red shift in the presence of 6 M guanidine hydrochloride. Immunization of inbred FvB/J female mice with purified recombinant TT-KK-ZP3 (25 μg/animal) led to generation of high antibody titers against the recombinant protein. The antibodies reacted specifically with ZP matrix surrounding mouse oocytes. Immunized mice showed significant reduction in fertility as compared to the control group. The studies described herein provide a simple method to produce and purify tag-free recombinant protein for the development of a contraceptive vaccine.
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Kapas, S; Hinson, J P
1996-01-01
1. The experiments described in this study were carried out to investigate the role of tyrosine kinase in the acute adrenal response to peptide hormone stimulation, and to determine whether the activity of this kinase may be subject to regulation by other intracellular signalling mechanisms in the adrenal zona glomerulosa. 2. Previous studies from this laboratory have shown that angiotensin II stimulates tyrosine kinase activity in the rat adrenal cortex. This study has shown, for the first time, that endothelin-1 also stimulates tyrosine kinase activity in this tissue. 3. Using the specific inhibitor of protein kinase C (PKC) activity, Ro 31-8220, we have shown that stimulation of tyrosine kinase activity, in response to endothelin-1, angiotensin II or the phorbol ester phorbol 12-myristate 13-acetate, is at least partly dependent on increased PKC activity. 4. The data presented also provide further evidence of cross-talk between signalling systems in the adrenal cortex. Corticotrophin and its intracellular second messenger, cyclic AMP, significantly attenuate the increment in tyrosine kinase activity seen in response to each of the effectors used. 5. The results of this study provide important new evidence for the regulation of protein kinases by other intracellular second messenger systems. PMID:8611168
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The Limit of Free Magnetic Energy in Active Regions
NASA Technical Reports Server (NTRS)
Moore, Ron; Falconer, David; Sterling, Alphonse
2012-01-01
By measuring from active-region magnetograms a proxy of the free energy in the active region fs magnetic field, it has been found previously that (1) there is an abrupt upper limit to the free energy the field can hold that increases with the amount of magnetic field in the active region, the active region fs magnetic flux content, and (2) the free energy is usually near its limit when the field explodes in a CME/flare eruption. That is, explosive active regions are concentrated in a main-sequence path bordering the free-energy ]limit line in (flux content, free-energy proxy) phase space. Here, from measurement of Marshall Space Flight Center vector magnetograms, we find the magnetic condition that underlies the free ]energy limit and the accompanying main sequence of explosive active regions. Using a suitable free ]energy proxy measured from vector magnetograms of 44 active regions, we find that (1) in active regions at and near their free ]energy limit, the ratio of magnetic-shear free energy to the non ]free magnetic energy the potential field would have is approximately 1 in the core field, the field rooted along the neutral line, and (2) this ratio is progressively less in active regions progressively farther below their free ]energy limit. This shows that most active regions in which this core-field energy ratio is much less than 1 cannot be triggered to explode; as this ratio approaches 1, most active regions become capable of exploding; and when this ratio is 1 or greater, most active regions are compelled to explode. From these results we surmise the magnetic condition that determines the free ]energy limit is the ratio of the free magnetic energy to the non-free energy the active region fs field would have were it completely relaxed to its potential ]field configuration, and that this ratio is approximately 1 at the free-energy limit and in the main sequence of explosive active regions.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
East, I.J.; Keenan, A.M.; Larson, S.M.
1984-08-31
The zona pellucida is an extracellular glycocalyx, made of three sulfated glycoproteins, that surrounds mammalian oocytes. Parenterally administered monoclonal antibodies specific for ZP-2, the most abundant zona protein, localize in the zona pellucida. When labeled with iodine-125, these monoclonal antibodies demonstrate a remarkably high target-to-nontarget tissue ratio and provide clear external radioimaging of ovarian tissue.
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Hernández-Pichardo, J E; Ducolomb, Y; Romo, S; Kjelland, M E; Fierro, R; Casillas, F; Betancourt, M
2016-01-01
In order to improve ICSI, appropiate sperm selection and oocyte activation is necessary. The objective of the present study was to determine the efficiency of fertilization using ICSI with chemically activated ovine oocytes and sperm selected by swim up (SU) or swim up + zona pellucida (SU + ZP) binding. Experiment 1, 4-20 replicates with total 821 in vitro matured oocytes were chemically activated with ethanol, calcium ionophore or ionomycin, to determine oocyte activation (precense of one PN). Treatments showed similar results (54, 47, 42 %, respectively) but statistically differents ( P < 0.05) than mechanical activated oocytes in sham, ICSI and sham injection (13, 25, 32 %, respectively) (10-17 replicates; n = 429). Experiment 2: Twelve ejaculates and 28 straws of semen were used (11-19 replicates). Sperm were selected by SU in BSA-TCM 199-H medium. A total of 2,294 fresh sperm and 2,760 from frozen-thawed semen were analyzed after SU or SU + ZP binding. Fresh sperm selected by SU showed acrosome reaction (AR) of 59 %, the sperm selected by SU + ZP binding increased AR to 91 %. In comparison, the AR of frozen-thawed sperm using SU or SU + ZP binding was 77 and 86 %, respectively ( P < 0.05). Experiment 3: fertilization in 200 mechanical activativated oocytes (17 replicates) was 4 %, but fertilization increased in ethanol activated oocytes after ICSI (12-28 %) (5-6 replicates). When fresh sperm only selected by SU were injected to 123 oocytes, a fertilization rate (28 %) was achieved; in sperm selected by SU + ZP was 25 % (73 oocytes). In comparison, in frozen-thawed sperm selected by SU, fertilization was 13 % (70 oocytes), whereas sperm from SU + ZP binding displayed 12 % (51 oocytes) ( P > 0.05). Chemical activation induces higher ovine oocyte activation than mechanical activation. Ethanol slightly displays higher oocyte activation than calcium ionophore and ionomicine. Sperm selection with SU
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Hung, Pei-hsuan; Miller, Marion G.; Meyers, Stuart A.; VandeVoort, Catherine A.
2008-01-01
Whether the main energy source for sperm motility is from oxidative phosphorylation or glycolysis has been long-debated in the field of reproductive biology. Using the rhesus monkey as a model, we examined the role of glycolysis and oxidative phosphorylation in sperm function by using alpha-chlorohydrin (ACH), a glycolysis inhibitor, and pentachlorophenol (PCP), an oxidative phosphorylation uncoupler. Sperm treated with ACH showed no change in percentage of motile sperm, although sperm motion was impaired. The ACH-treated sperm did not display either hyperactivity- or hyperactivation-associated changes in protein tyrosine phosphorylation. When treated with PCP, sperm motion parameters were affected by the highest level of PCP (200 μM); however, PCP did not cause motility impairments even after chemical activation. Sperm treated with PCP were able to display hyperactivity and tyrosine phosphorylation after chemical activation. In contrast with motility measurements, treatment with either the glycolytic inhibitor or the oxidative phosphorylation inhibitor did not affect sperm-zona binding and zona-induced acrosome reaction. The results suggest glycolysis is essential to support sperm motility, hyperactivity, and protein tyrosine phosphorylation, while energy from oxidative phosphorylation is not necessary for hyperactivated sperm motility, tyrosine phosphorylation, sperm-zona binding, and acrosome reaction in the rhesus macaque. PMID:18480469
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Thermal effects in laser-assisted pre-embryo zona drilling
NASA Astrophysics Data System (ADS)
Douglas-Hamilton, Diarmaid H.; Conia, Jerome D.
2001-04-01
Diode lasers ((lambda) equals 1480 nm) are used with in vitro fertilization to dissect the zone pellucida (shell) of pre- embryos. A focused laser beam is applied in vitro to form a channel or trench in the zona pellucida. The procedure is used to facilitate biopsy or as a promoter of embryo hatching. We present examples and measurements of zona pellucida ablation using animal models. In using the laser it is vital not to damage pre-embryo cells, e.g., by overheating. In order to define safe regimes we have derived some thermal side effects of zona pellucida removal. The temperature profile in the beam and vicinity is predicted as function of laser pulse duration and power. In a crossed- beam experiment a HeNe laser probe is used to detect the temperature-induced change in the refractive index of an aqueous solution, and estimate local thermal gradient. We find that the diode laser beam produces superheated water approaching 200 degree(s)C on the beam axis. Thermal histories during and following the laser pulse are given for regions in the neighborhood of the beam. We conclude that an optimum regime exists with pulse duration
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Schimmel, Tim; Cohen, Jacques; Saunders, Helen; Alikani, Mina
2014-12-01
Does laser-assisted zona thinning of cleavage stage mouse embryos facilitate hatching in vitro? No, unlike laser zona opening, zona thinning does not facilitate embryo hatching. Artificial opening of the zona pellucida facilitates hatching of mouse and human embryos. Laser-assisted zona thinning has also been used for the purpose of assisted hatching of human embryos but it has not been properly investigated in an animal model; thinning methods have produced inconsistent clinical results. Time-lapse microscopy was used to study the hatching process in the mouse after zona opening and zona thinning; a control group of embryos was not zona-manipulated but exposed to the same laser energy. Eight-cell CB6F1/J mouse embryos were pooled and allocated to three groups (n = 56 per group): A control group of embryos that were exposed to a dose of laser energy focused outside the zona pellucida (zona intact); one experimental group of embryos in which the zona pellucida was opened by complete ablation using the same total number of pulses as the control group; a second experimental group of embryos in which the zona pellucida was thinned to establish a smooth lased area using the same number of pulses as used in the other two groups. The width of the zona opening was 25 μm and width of the thinned area was 35 μm. Development was monitored by time-lapse microscopy. Overall treatment differences for continuous variables were analyzed by analysis of variance and pairwise comparisons using the Student t-test allowing for unequal variances, while for categorical data, a standard chi-squared test was utilized for all pairwise comparisons. The frequency of complete hatching was 33.9% in the control group, 94.4% after zona opening, and 39.3% after zona thinning (overall group comparison, P < 0.0001). Overall, 60.7% of the zona-thinned embryos did not complete the hatching process and remained trapped within the zona; when they did hatch, they did not necessarily hatch from the zona
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Ma, Xiao-Xin; Zhu, Jun-Quan; Zhou, Hong; Yang, Wan-Xi
2012-02-01
The egg envelope is an essential structure occurring during oogenesis. It plays an important role during the process of fertilization in the large yellow croaker Pseudosciaena crocea. Elucidation of egg envelope formation helps us to understand fertilization mechanisms in teleosts. In the present work, we studied the formation of egg envelope in P. crocea by light microscopy, as well as by transmission and scanning electron microscopy. Four layers exist outside the oocyte plasmalemma, i.e., theca cell layer, basal membrane, granulosa cell layer and zona radiata. According to our observation, zona radiata is a multilaminar structure just like the same structure reported in teleosts, but the origin of this structure is a little different. Before it is formed, a peripheral space filled with different density of vesicles is the place where zona radiata is formed. Zona radiata (Z1) is secreted only by oocyte itself, it belongs to the primary envelope; zona radiata 2 (Z2) and zona radiata 3 (Z3) belong to the secondary envelope, because the two layers are formed after granulosa cells appear, and microvilli participate this process. It is very interesting that Z2 and Z3 are situated between Z1 and the granulosa cell first, but they translocate to the other side of Z1. This microanatomy difference may due to the participation of microvilli. The new finding about egg envelope formation in P. crocea will help us to do further investigation on fertilization mechanisms and will make artificial breeding possible which may contribute to the resource recovery of this species. Copyright © 2011 Elsevier Ltd. All rights reserved.
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Florman, H M; First, N L
1988-08-01
The effects of accessory sex gland secretions on the zona pellucida-induced acrosome reaction of bovine spermatozoa were investigated. Soluble extracts of zonae pellucidae initiated exocytosis in ejaculated spermatozoa. This process had an ED50 of 20 ng/microliter zona pellucida protein and saturated at 50 ng/microliter (Florman and First, 1988. Dev. Biol. 128, 453-463). In epididymal sperm this dose-response relationship was shifted toward greater agonist concentrations by at least a factor of 10(3). Reconstitution of high potency agonist response was achieved in vitro by incubation of epididymal sperm with bovine seminal plasma. Reconstitution was dependent on the seminal plasma protein concentration. The ED50 of this process was 62 micrograms protein/10(8) sperm and saturation was observed with 124 micrograms protein/10(8) sperm. Agonist responses in reconstituted epididymal sperm and in ejaculated sperm were indistinguishable with regard to dependence on the zona pellucida protein concentration and the kinetics of induced acrosome reactions. Kinetic studies suggest that reconstitution is due to adsorption of regulatory factors from seminal plasma. In addition to the positive regulatory elements responsible for reconstituting activity, seminal plasma also contains negative regulatory elements which inhibit agonist response. These negative factors are inactivated during sperm capacitation, permitting the expression of positive regulators. Acting together, these regulatory elements could coordinate high affinity agonist response with the availability of eggs in vivo.
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Human sperm bind to the N-terminal domain of ZP2 in humanized zonae pellucidae in transgenic mice
Baibakov, Boris; Boggs, Nathan A.; Yauger, Belinda; Baibakov, Galina
2012-01-01
Fertilization requires taxon-specific gamete recognition, and human sperm do not bind to zonae pellucidae (ZP1–3) surrounding mouse eggs. Using transgenesis to replace endogenous mouse proteins with human homologues, gain-of-function sperm-binding assays were established to evaluate human gamete recognition. Human sperm bound only to zonae pellucidae containing human ZP2, either alone or coexpressed with other human zona proteins. Binding to the humanized matrix was a dominant effect that resulted in human sperm penetration of the zona pellucida and accumulation in the perivitelline space, where they were unable to fuse with mouse eggs. Using recombinant peptides, the site of gamete recognition was located to a defined domain in the N terminus of ZP2. These results provide experimental evidence for the role of ZP2 in mediating sperm binding to the zona pellucida and support a model in which human sperm–egg recognition is dependent on an N-terminal domain of ZP2, which is degraded after fertilization to provide a definitive block to polyspermy. PMID:22734000
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Targeting the zona pellucida for immunocontraception: a minireview.
Tesarik, J
1995-12-01
This minireview summarizes the main data relevant to the development of contraceptive vaccines based on zona pellucida (ZP) antigens, as well as the pros and the cons of this immunocontraceptive strategy. Even though the antifertility efficacy of anti-ZP antibodies in humans is not corroborated by a clear relationship between spontaneous autoimmunization against the ZP and infertility, passive and active immunization studies in laboratory animals have provided convincing results. The contraceptive action of anti-ZP antibodies, targeting events situated upstream of gamete fusion, is devoid of potential ethical concerns related to the destruction of early embryos. The high protein content of the mammalian ZP, knowledge of the complete amino acid sequence of the major ZP proteins, and the high degree of sequence homology between individual species all favour the rapid advancement of anti-ZP vaccine projects. However, certain sequences of ZP proteins, when incorporated into the vaccine construct, activate CD4+ T cells of the recipient organism to direct a cellular immune attack (autoimmune oophoritis) to other functionally relevant ovarian components (primordial follicles, steroidogenic cells). The search for the optimal combination of B cell and T cell epitopes in the vaccine construct will hopefully overcome this problem.
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Free Time Motivation and Physical Activity in Middle School Children
ERIC Educational Resources Information Center
Kozub, Francis M.; Farmer, James
2011-01-01
This study examined free time motivation and physical activity in 68 middle school children from a rural public school system (N = 24) and a private school located in the same area of the Midwest (N = 44). Results indicated that free time motivation did not explain variability in physical activity behavior during free time or while students were…
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Multi-sensor physical activity recognition in free-living.
Ellis, Katherine; Godbole, Suneeta; Kerr, Jacqueline; Lanckriet, Gert
Physical activity monitoring in free-living populations has many applications for public health research, weight-loss interventions, context-aware recommendation systems and assistive technologies. We present a system for physical activity recognition that is learned from a free-living dataset of 40 women who wore multiple sensors for seven days. The multi-level classification system first learns low-level codebook representations for each sensor and uses a random forest classifier to produce minute-level probabilities for each activity class. Then a higher-level HMM layer learns patterns of transitions and durations of activities over time to smooth the minute-level predictions. [Formula: see text].
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Wang, Weiye; Wang, Lishan; Endoh, Akira; Hummelke, Geoffrey; Hawks, Christina L; Hornsby, Peter J
2005-01-01
In order to establish whether there are differences in DNA-binding proteins between zona fasciculata (ZF) and zona reticularis (ZR) cells of the human adrenal cortex, we prepared nuclear extracts from separated ZF and ZR cells. The formation of DNA-protein complexes was studied using an element in the first intron of the type I and type II 3beta-hydroxysteroid dehydrogenase genes (HSD3B1 and HSD3B2). Using the element in the HSD3B2 gene as a probe, a complex (C1) was formed with extracts from ZF cells but was formed only at a low level with ZR cell extracts. Another pair of complexes (C2/C3) was formed with both ZF and ZR cell extracts. The ZF-specific protein forming C1 was enriched by column chromatography on DEAE-Sepharose and carboxymethyl-Sepharose. Oligonucleotide competition analysis on the enriched fraction gave results consistent with those obtained on the unfractionated material. A further enrichment was brought about by passing the protein over an oligonucleotide affinity column based on the HSD3B2 element. The protein bound to the column was identified as alpha-enolase by mass spectrometry. Although alpha-enolase is a glycolytic enzyme, it binds to specific DNA sequences and has been found to be present in nuclei of various cell types. We performed immunohistochemistry on sections of adult human adrenal cortex and found alpha-enolase to be located in nuclei of ZF cells but to be predominantly cytoplasmic in ZR cells. Transfection of an alpha-enolase expression vector into NCI-H295R human adrenocortical cells increased HSD3B2 promoter activity, suggesting a possible functional role for this protein in regulation of HSD3B2 expression.
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The Magnetic Free Energy in Active Regions
NASA Technical Reports Server (NTRS)
Metcalf, Thomas R.; Mickey, Donald L.; LaBonte, Barry J.
2001-01-01
The magnetic field permeating the solar atmosphere governs much of the structure, morphology, brightness, and dynamics observed on the Sun. The magnetic field, especially in active regions, is thought to provide the power for energetic events in the solar corona, such as solar flares and Coronal Mass Ejections (CME) and is believed to energize the hot coronal plasma seen in extreme ultraviolet or X-rays. The question remains what specific aspect of the magnetic flux governs the observed variability. To directly understand the role of the magnetic field in energizing the solar corona, it is necessary to measure the free magnetic energy available in active regions. The grant now expiring has demonstrated a new and valuable technique for observing the magnetic free energy in active regions as a function of time.
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Rapid binge-like eating and body weight gain driven by zona incerta GABA neuron activation.
Zhang, Xiaobing; van den Pol, Anthony N
2017-05-26
The neuronal substrate for binge eating, which can at times lead to obesity, is not clear. We find that optogenetic stimulation of mouse zona incerta (ZI) γ-aminobutyric acid (GABA) neurons or their axonal projections to paraventricular thalamus (PVT) excitatory neurons immediately (in 2 to 3 seconds) evoked binge-like eating. Minimal intermittent stimulation led to body weight gain; ZI GABA neuron ablation reduced weight. ZI stimulation generated 35% of normal 24-hour food intake in just 10 minutes. The ZI cells were excited by food deprivation and the gut hunger signal ghrelin. In contrast, stimulation of excitatory axons from the parasubthalamic nucleus to PVT or direct stimulation of PVT glutamate neurons reduced food intake. These data suggest an unexpected robust orexigenic potential for the ZI GABA neurons. Copyright © 2017, American Association for the Advancement of Science.
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Performance of Activity Classification Algorithms in Free-living Older Adults
Sasaki, Jeffer Eidi; Hickey, Amanda; Staudenmayer, John; John, Dinesh; Kent, Jane A.; Freedson, Patty S.
2015-01-01
Purpose To compare activity type classification rates of machine learning algorithms trained on laboratory versus free-living accelerometer data in older adults. Methods Thirty-five older adults (21F and 14M ; 70.8 ± 4.9 y) performed selected activities in the laboratory while wearing three ActiGraph GT3X+ activity monitors (dominant hip, wrist, and ankle). Monitors were initialized to collect raw acceleration data at a sampling rate of 80 Hz. Fifteen of the participants also wore the GT3X+ in free-living settings and were directly observed for 2-3 hours. Time- and frequency- domain features from acceleration signals of each monitor were used to train Random Forest (RF) and Support Vector Machine (SVM) models to classify five activity types: sedentary, standing, household, locomotion, and recreational activities. All algorithms were trained on lab data (RFLab and SVMLab) and free-living data (RFFL and SVMFL) using 20 s signal sampling windows. Classification accuracy rates of both types of algorithms were tested on free-living data using a leave-one-out technique. Results Overall classification accuracy rates for the algorithms developed from lab data were between 49% (wrist) to 55% (ankle) for the SVMLab algorithms, and 49% (wrist) to 54% (ankle) for RFLab algorithms. The classification accuracy rates for SVMFL and RFFL algorithms ranged from 58% (wrist) to 69% (ankle) and from 61% (wrist) to 67% (ankle), respectively. Conclusion Our algorithms developed on free-living accelerometer data were more accurate in classifying activity type in free-living older adults than our algorithms developed on laboratory accelerometer data. Future studies should consider using free-living accelerometer data to train machine-learning algorithms in older adults. PMID:26673129
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Uppangala, Shubhashree; D'Souza, Fiona; Pudakalakatti, Shivanand; Atreya, Hanudatta S; Raval, Keyur; Kalthur, Guruprasad; Adiga, Satish Kumar
2016-12-01
Laser assisted zona hatching (LAH) is a routinely used therapeutic intervention in assisted reproductive technology for patients with poor prognosis. However, results are not conclusive in demonstrating the benefits of zona hatching in improving the pregnancy rate. Recent observations on LAH induced genetic instability in animal embryos prompted us to look into the effects of laser assisted zona hatching on the human preimplantation embryo quality and metabolic uptake using high resolution nuclear magnetic resonance (NMR) technology. This experimental prospective study included fifty embryos from twenty-five patients undergoing intra cytoplasmic sperm injection. Embryo quality assessment followed by profiling of spent media for the non-invasive evaluation of metabolites was performed using NMR spectroscopy 24 hours after laser treatment and compared with that of non-treated sibling embryos. Both cell number and embryo quality on day 3 of development did not vary significantly between the two groups at 24 hours post laser treatment interval. Time lapse monitoring of the embryos for 24 hours did not reveal blastomere fragmentation adjacent to the point of laser treatment. Similarly, principal component analysis of metabolites did not demonstrate any variation across the groups. These results suggest that laser assisted zona hatching does not affect human preimplantation embryo morphology and metabolism at least until 24 hours post laser assisted zona hatching. However, studies are required to elucidate laser induced metabolic and developmental changes at extended time periods. AH: assisted hatching; ART: assisted reproductive technology; DNA: deoxy-ribo nucleic acid; LAH: laser assisted hatching; MHz: megahertz; NMR: nuclear magnetic resonance; PCA: principal component analysis; PGD: preimplantation genetic diagnosis; TLM: time lapse monitoring.
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Performance of Activity Classification Algorithms in Free-Living Older Adults.
Sasaki, Jeffer Eidi; Hickey, Amanda M; Staudenmayer, John W; John, Dinesh; Kent, Jane A; Freedson, Patty S
2016-05-01
The objective of this study is to compare activity type classification rates of machine learning algorithms trained on laboratory versus free-living accelerometer data in older adults. Thirty-five older adults (21 females and 14 males, 70.8 ± 4.9 yr) performed selected activities in the laboratory while wearing three ActiGraph GT3X+ activity monitors (in the dominant hip, wrist, and ankle; ActiGraph, LLC, Pensacola, FL). Monitors were initialized to collect raw acceleration data at a sampling rate of 80 Hz. Fifteen of the participants also wore GT3X+ in free-living settings and were directly observed for 2-3 h. Time- and frequency-domain features from acceleration signals of each monitor were used to train random forest (RF) and support vector machine (SVM) models to classify five activity types: sedentary, standing, household, locomotion, and recreational activities. All algorithms were trained on laboratory data (RFLab and SVMLab) and free-living data (RFFL and SVMFL) using 20-s signal sampling windows. Classification accuracy rates of both types of algorithms were tested on free-living data using a leave-one-out technique. Overall classification accuracy rates for the algorithms developed from laboratory data were between 49% (wrist) and 55% (ankle) for the SVMLab algorithms and 49% (wrist) to 54% (ankle) for the RFLab algorithms. The classification accuracy rates for SVMFL and RFFL algorithms ranged from 58% (wrist) to 69% (ankle) and from 61% (wrist) to 67% (ankle), respectively. Our algorithms developed on free-living accelerometer data were more accurate in classifying the activity type in free-living older adults than those on our algorithms developed on laboratory accelerometer data. Future studies should consider using free-living accelerometer data to train machine learning algorithms in older adults.
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The practical side of immunocontraception: zona proteins and wildlife.
Kirkpatrick, J F; Rowan, A; Lamberski, N; Wallace, R; Frank, K; Lyda, R
2009-12-01
With shrinking habitat, the humane control of certain wildlife populations is relevant. The contraceptive vaccine based on native porcine zona pellucida (PZP) has been applied to various wildlife populations for 20 years. Prominent efforts include wild horses, urban deer, zoo animals and African elephants, among others. This approach has been successful in managing entire populations and to date, no significant debilitating short- or long-term health effects have been documented.
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The temporal structures and functional significance of scale-free brain activity
He, Biyu J.; Zempel, John M.; Snyder, Abraham Z.; Raichle, Marcus E.
2010-01-01
SUMMARY Scale-free dynamics, with a power spectrum following P ∝ f-β, are an intrinsic feature of many complex processes in nature. In neural systems, scale-free activity is often neglected in electrophysiological research. Here, we investigate scale-free dynamics in human brain and show that it contains extensive nested frequencies, with the phase of lower frequencies modulating the amplitude of higher frequencies in an upward progression across the frequency spectrum. The functional significance of scale-free brain activity is indicated by task performance modulation and regional variation, with β being larger in default network and visual cortex and smaller in hippocampus and cerebellum. The precise patterns of nested frequencies in the brain differ from other scale-free dynamics in nature, such as earth seismic waves and stock market fluctuations, suggesting system-specific generative mechanisms. Our findings reveal robust temporal structures and behavioral significance of scale-free brain activity and should motivate future study on its physiological mechanisms and cognitive implications. PMID:20471349
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Temperature and UV light affect the activity of marine cell-free enzymes
NASA Astrophysics Data System (ADS)
Thomson, Blair; Hepburn, Christopher David; Lamare, Miles; Baltar, Federico
2017-09-01
Microbial extracellular enzymatic activity (EEA) is the rate-limiting step in the degradation of organic matter in the oceans. These extracellular enzymes exist in two forms: cell-bound, which are attached to the microbial cell wall, and cell-free, which are completely free of the cell. Contrary to previous understanding, cell-free extracellular enzymes make up a substantial proportion of the total marine EEA. Little is known about these abundant cell-free enzymes, including what factors control their activity once they are away from their sites (cells). Experiments were run to assess how cell-free enzymes (excluding microbes) respond to ultraviolet radiation (UVR) and temperature manipulations, previously suggested as potential control factors for these enzymes. The experiments were done with New Zealand coastal waters and the enzymes studied were alkaline phosphatase (APase), β-glucosidase, (BGase), and leucine aminopeptidase (LAPase). Environmentally relevant UVR (i.e. in situ UVR levels measured at our site) reduced cell-free enzyme activities by up to 87 % when compared to controls, likely a consequence of photodegradation. This effect of UVR on cell-free enzymes differed depending on the UVR fraction. Ambient levels of UV radiation were shown to reduce the activity of cell-free enzymes for the first time. Elevated temperatures (15 °C) increased the activity of cell-free enzymes by up to 53 % when compared to controls (10 °C), likely by enhancing the catalytic activity of the enzymes. Our results suggest the importance of both UVR and temperature as control mechanisms for cell-free enzymes. Given the projected warming ocean environment and the variable UVR light regime, it is possible that there could be major changes in the cell-free EEA and in the enzymes contribution to organic matter remineralization in the future.
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Investigation of habitual pitch during free play activities for preschool-aged children.
Chen, Yang; Kimelman, Mikael D Z; Micco, Katie
2009-01-01
This study is designed to compare the habitual pitch measured in two different speech activities (free play activity and traditionally used structured speech activity) for normally developing preschool-aged children to explore to what extent preschoolers vary their vocal pitch among different speech environments. Habitual pitch measurements were conducted for 10 normally developing children (2 boys, 8 girls) between the ages of 31 months and 71 months during two different activities: (1) free play; and (2) structured speech. Speech samples were recorded using a throat microphone connected with a wireless transmitter in both activities. The habitual pitch (in Hz) was measured for all collected speech samples by using voice analysis software (Real-Time Pitch). Significantly higher habitual pitch is found during free play in contrast to structured speech activities. In addition, there is no showing of significant difference of habitual pitch elicited across a variety of structured speech activities. Findings suggest that the vocal usage of preschoolers appears to be more effortful during free play than during structured activities. It is recommended that a comprehensive evaluation for young children's voice needs to be based on the speech/voice samples collected from both free play and structured activities.
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NASA's current activities in free space optical communications
NASA Astrophysics Data System (ADS)
Edwards, Bernard L.
2017-11-01
NASA and other space agencies around the world are currently developing free space optical communication systems for both space-to-ground links and space-to-space links. This paper provides an overview of NASA's current activities in free space optical communications with a focus on Near Earth applications. Activities to be discussed include the Lunar Laser Communication Demonstration, the Laser Communications Relay Demonstration, and the commercialization of the underlying technology. The paper will also briefly discuss ongoing efforts and studies for Deep Space optical communications. Finally the paper will discuss the development of international optical communication standards within the Consultative Committee for Space Data Systems.
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Cervera, R P; Garcia-Ximénez, F
2003-10-01
The purpose of this study was to test the effectiveness of one two-step (A) and two one-step (B1 and B2) vitrification procedures on denuded expanded or hatching rabbit blastocysts held in standard sealed plastic straws as a possible model for human blastocysts. The effect of blastocyst size was also studied on the basis of three size categories (I: diameter <200 micro m; II: diameter 200-299 micro m; III: diameter >/==" BORDER="0">300 micro m). Rabbit expanded or hatching blastocysts were vitrified at day 4 or 5. Before vitrification, the zona pellucida was removed using acidic phosphate buffered saline. For the two-step procedure, prior to vitrification, blastocysts were pre- equilibrated in a solution containing 10% dimethyl sulphoxide (DMSO) and 10% ethylene glycol (EG) for 1 min. Different final vitrification solutions were compared: 20% DMSO and 20% EG with (A and B1) or without (B2) 0.5 mol/l sucrose. Of 198 vitrified blastocysts, 181 (91%) survived, regardless of the vitrification procedure applied. Vitrification procedure A showed significantly higher re-expansion (88%), attachment (86%) and trophectoderm outgrowth (80%) rates than the two one-step vitrification procedures, B1 and B2 (46 and 21%, 20 and 33%, and 18 and 23%, respectively). After warming, blastocysts of greater size (II and III) showed significantly higher attachment (54 and 64%) and trophectoderm outgrowth (44 and 58%) rates than smaller blastocysts (I, attachment: 29%; trophectoderm outgrowth: 25%). These result demonstrate that denuded expanded or hatching rabbit blastocysts of greater size can be satisfactorily vitrified by use of a two-step procedure. The similarity of vitrification solutions used in humans could make it feasible to test such a procedure on human denuded blastocysts of different sizes.
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Body mass index is not associated with sperm-zona pellucida binding ability in subfertile males.
Sermondade, Nathalie; Dupont, Charlotte; Faure, Céline; Boubaya, Marouane; Cédrin-Durnerin, Isabelle; Chavatte-Palmer, Pascale; Sifer, Christophe; Lévy, Rachel
2013-09-01
Lifestyle factors, such as weight and nutritional status may affect male fertility, including sperm fertilization ability. The objective of this retrospective study was to evaluate the association between body mass index (BMI) and sperm-zona pellucida binding ability assessed according to the zona binding (ZB) test, which has been described to be a relevant diagnostic tool for the prediction of in vitro fertilization (IVF) ability. Three hundred and six male patients from couples diagnosed with primary idiopathic or mild male factor infertility were included. Correlations between BMI and semen parameters according to ZB test indices were assessed, together with frequencies of positive and negative tests across the BMI categories. In this selected population, BMI was not related to conventional semen parameters or sperm quality assessed according to the ability of spermatozoa to bind to the zona pellucida. The previously described poor outcomes of IVF procedures in cases of male obesity could be due to other sperm defects, such as alterations of sperm capacitation or acrosome reaction. The link between male BMI and biological outcomes during IVF procedures, such as fertilization rates, should be further evaluated.
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The Maximum Free Magnetic Energy Allowed in a Solar Active Region
NASA Technical Reports Server (NTRS)
Moore, Ronald L.; Falconer, David A.
2009-01-01
Two whole-active-region magnetic quantities that can be measured from a line-of-sight magnetogram are (sup L) WL(sub SG), a gauge of the total free energy in an active region's magnetic field, and sup L(sub theta), a measure of the active region's total magnetic flux. From these two quantities measured from 1865 SOHO/MDI magnetograms that tracked 44 sunspot active regions across the 0.5 R(sub Sun) central disk, together with each active region's observed production of CMEs, X flares, and M flares, Falconer et al (2009, ApJ, submitted) found that (1) active regions have a maximum attainable free magnetic energy that increases with the magnetic size (sup L) (sub theta) of the active region, (2) in (Log (sup L)WL(sub SG), Log(sup L) theta) space, CME/flare-productive active regions are concentrated in a straight-line main sequence along which the free magnetic energy is near its upper limit, and (3) X and M flares are restricted to large active regions. Here, from (a) these results, (b) the observation that even the greatest X flares produce at most only subtle changes in active region magnetograms, and (c) measurements from MSFC vector magnetograms and from MDI line-of-sight magnetograms showing that practically all sunspot active regions have nearly the same area-averaged magnetic field strength: =- theta/A approximately equal to 300 G, where theta is the active region's total photospheric flux of field stronger than 100 G and A is the area of that flux, we infer that (1) the maximum allowed ratio of an active region's free magnetic energy to its potential-field energy is 1, and (2) any one CME/flare eruption releases no more than a small fraction (less than 10%) of the active region's free magnetic energy. This work was funded by NASA's Heliophysics Division and NSF's Division of Atmospheric Sciences.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
De Lean, A.; Cantin, M.
1986-03-05
The authors have previously reported that atrial natriuretic factor (ANF) potently inhibits PGE or forskolin-stimulation aldosterone secretion in bovine zona glomerulosa (ZG) by acting through specific high affinity receptors. In order to evaluate the functional role of the regulatory protein N/sub i/ and the inhibition of adenylate cyclase activity (AC) in ZG, the authors have studied the effect of treatment with PT on inhibition by ANF of aldosterone production. Primary cultures of ZG were treated for 18 hours in serum-free F12 medium with (0-100 ng/ml PT). No effect of PT pretreatment was observed either on basal, PGE-stimulated or ANF-inhibited levelsmore » of steroidogenesis. When membranes prepared from control ZG were ADP-ribosylated with (/sup 32/P) NAD in the presence of PT, two toxin-specific bands with 39 Kd and 41 Kd were documented on SDS gel. Cell pretreatment with as low as 1 ng/ml drastically reduced further labelling of these two bands while higher doses completely abolished them. Since PT treatment covalently modifies completely the toxin substrate without altering ANF inhibition of adrenal steroidogenesis, the authors conclude that N/sub i/ is not involved in the mode of action of ANF on aldosterone production.« less
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Culture of bovine embryos on a polydimethylsiloxane (PDMS) microwell plate.
Akagi, Satoshi; Hosoe, Misa; Matsukawa, Kazutsugu; Ichikawa, Akihiko; Tanikawa, Tamio; Takahashi, Seiya
2010-08-01
We fabricated a polydimethylsiloxane (PDMS)-based microwell plate (PDMS-MP) containing 100 microwells with a rounded bottom and examined whether it can be used for culture of individual in vitro fertilized (IVF) embryos or parthenogenetically activated zona-free embryos in cattle. In Experiment 1, we examined the in vitro developmental ability of IVF embryos cultured individually on PDMS-MP. After IVF, 20 embryos were transferred into 100 microl drops on PDMS-MP and cultured individually in each well of PDMS-MP (PDMS group). After 7 days of culture, the embryos in the PDMS group developed to the blastocyst stage at the same rate of those in the control group cultured in a group of 20 embryos without PDMS-MP. There were no differences in total number of cells and the ratio of inner cell mass to total cells between the PDMS and control groups. In Experiment 2, we examined the in vitro developmental ability of parthenogenetically activated zona-free bovine embryos cultured individually on PDMS-MP. The zona-free embryos were cultured individually in each well of a PDMS-MP or in each well produced by pressing a darning needle onto the bottom of a culture dish (WOW group). After 7 days of culture, the blastocyst formation rate and cell number of blastocysts in the PDMS group did not differ from those of the zona-intact embryos in the control group. Also, there were no differences in the blastocyst formation rate and cell number of blastocysts between the WOW and PDMS groups. These results suggest that the culture system using PDMS-MP is useful for individual embryos or zona-free embryos in cattle.
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Hanley, Gregory P; Tiger, Jeffrey H; Ingvarsson, Einar T; Cammilleri, Anthony P
2009-01-01
The present study evaluated the effects of classwide satiation and embedded reinforcement procedures on preschoolers' activity preferences during scheduled free-play periods. The goal of the study was to increase time allocation to originally nonpreferred, but important, activities (instructional zone, library, and science) while continuing to provide access to all free-play activities. The satiation intervention applied to preferred activities resulted in increased time allocation to the instructional and science activities, the customized embedded reinforcement interventions resulted in increased time allocation to all three target activities, and high levels of attendance to the instructional and library activities were maintained during follow-up observations. Implications for the design of preschool free-play periods are discussed. PMID:19721728
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Hanley, Gregory P; Tiger, Jeffrey H; Ingvarsson, Einar T; Cammilleri, Anthony P
2009-01-01
The present study evaluated the effects of classwide satiation and embedded reinforcement procedures on preschoolers' activity preferences during scheduled free-play periods. The goal of the study was to increase time allocation to originally nonpreferred, but important, activities (instructional zone, library, and science) while continuing to provide access to all free-play activities. The satiation intervention applied to preferred activities resulted in increased time allocation to the instructional and science activities, the customized embedded reinforcement interventions resulted in increased time allocation to all three target activities, and high levels of attendance to the instructional and library activities were maintained during follow-up observations. Implications for the design of preschool free-play periods are discussed.
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Functional TASK-3-Like Channels in Mitochondria of Aldosterone-Producing Zona Glomerulosa Cells.
Yao, Junlan; McHedlishvili, David; McIntire, William E; Guagliardo, Nick A; Erisir, Alev; Coburn, Craig A; Santarelli, Vincent P; Bayliss, Douglas A; Barrett, Paula Q
2017-08-01
Ca 2+ drives aldosterone synthesis in the cytosolic and mitochondrial compartments of the adrenal zona glomerulosa cell. Membrane potential across each of these compartments regulates the amplitude of the Ca 2+ signal; yet, only plasma membrane ion channels and their role in regulating cell membrane potential have garnered investigative attention as pathological causes of human hyperaldosteronism. Previously, we reported that genetic deletion of TASK-3 channels (tandem pore domain acid-sensitive K + channels) from mice produces aldosterone excess in the absence of a change in the cell membrane potential of zona glomerulosa cells. Here, we report using yeast 2-hybrid, immunoprecipitation, and electron microscopic analyses that TASK-3 channels are resident in mitochondria, where they regulate mitochondrial morphology, mitochondrial membrane potential, and aldosterone production. This study provides proof of principle that mitochondrial K + channels, by modulating inner mitochondrial membrane morphology and mitochondrial membrane potential, have the ability to play a pathological role in aldosterone dysregulation in steroidogenic cells. © 2017 American Heart Association, Inc.
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Kendrick, K M; Hinton, M R; Baldwin, B A
1991-05-31
In order to establish which neurotransmitters may influence the activity of zona incerta neurones in the sheep which respond selectively to the sight or ingestion of food, we have measured the release of amino acid and monoamine neurotransmitters from this region using microdialysis sampling. Co-ordinates for the placement of microdialysis probes in regions of the zona incerta where cells respond to the sight or ingestion of food were first established by making single-unit extracellular recordings. When animals were food-deprived results showed that release of gamma-aminobutyric acid (GABA) was increased in response to the sight and ingestion of food but not of aspartate, glutamate, taurine, noradrenaline, dopamine or serotonin. This release of GABA was absent when the animals were shown non-food objects or saw or ingested salt solutions. When the same animals were physiologically sodium-depleted GABA release was evoked by the sight and ingestion of salt solutions and release following the sight and ingestion of food was significantly reduced. These results provide further evidence that GABA is an important neurotransmitter in neural circuits controlling the regulation of food intake.
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Lee, YingHua; Takenaka, Koji; Kanosue, Kazuyuki
2015-09-01
Physical activity contributes to children's physical and mental well-being. Research suggests that active free play helps to maintain and increase physical activity in children and also contributes to social and emotional well-being. To date, these studies have focused on Western countries. Thus, this study was conducted to gain insights into the factors of perceptions of fun, barriers, and facilitators affecting active free play from the perspective of Japanese children using focus group interviews. In Japan, 12 focus groups were conducted with 60 children aged 9-11 years. Children's perceptions of fun in active free play were categorized into socializing, achievement, emotions, and freedom. Additionally, active boys' groups were interested in free play and adventure play; girls' groups were interested in free play with less physical movement and challenges; inactive boys' groups were interested in relaxing and competitive play with bodily contact. However, children mentioned that busy schedules, weather, and health-related factors acted as main barriers. Lastly, children noted facilitators include setting schedules, having access to equipment and playgrounds, and holding special events. The findings provide insights into active free play-related factors for active and inactive Japanese children and also clarify the differences between Japanese and Western children. Such findings will contribute to designing interventions to increase active free play. © The Author(s) 2013.
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Influence of Activity Monitor Location and Bout Duration on Free-Living Physical Activity
ERIC Educational Resources Information Center
Heil, Daniel P.; Bennett, Gary G.; Bond, Kathleen S.; Webster, Michael D.; Wolin, Kathleen Y.
2009-01-01
The purpose of this study was to evaluate the influence of the location (ankle, hip, wrist) where an activity monitor (AM) is worn and of the minimum bout duration (BD) on physical activity (PA) variables during free-living monitoring. Study 1 participants wore AMs at three locations for 1 day while wearing the Intelligent Device for Energy…
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Orbitofrontal cortical activity during repeated free choice.
Campos, Michael; Koppitch, Kari; Andersen, Richard A; Shimojo, Shinsuke
2012-06-01
Neurons in the orbitofrontal cortex (OFC) have been shown to encode subjective values, suggesting a role in preference-based decision-making, although the precise relation to choice behavior is unclear. In a repeated two-choice task, subjective values of each choice can account for aggregate choice behavior, which is the overall likelihood of choosing one option over the other. Individual choices, however, are impossible to predict with knowledge of relative subjective values alone. In this study we investigated the role of internal factors in choice behavior with a simple but novel free-choice task and simultaneous recording from individual neurons in nonhuman primate OFC. We found that, first, the observed sequences of choice behavior included periods of exceptionally long runs of each of two available options and periods of frequent switching. Neither a satiety-based mechanism nor a random selection process could explain the observed choice behavior. Second, OFC neurons encode important features of the choice behavior. These features include activity selective for exceptionally long runs of a given choice (stay selectivity) as well as activity selective for switches between choices (switch selectivity). These results suggest that OFC neural activity, in addition to encoding subjective values on a long timescale that is sensitive to satiety, also encodes a signal that fluctuates on a shorter timescale and thereby reflects some of the statistically improbable aspects of free-choice behavior.
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Orbitofrontal cortical activity during repeated free choice
Koppitch, Kari; Andersen, Richard A.; Shimojo, Shinsuke
2012-01-01
Neurons in the orbitofrontal cortex (OFC) have been shown to encode subjective values, suggesting a role in preference-based decision-making, although the precise relation to choice behavior is unclear. In a repeated two-choice task, subjective values of each choice can account for aggregate choice behavior, which is the overall likelihood of choosing one option over the other. Individual choices, however, are impossible to predict with knowledge of relative subjective values alone. In this study we investigated the role of internal factors in choice behavior with a simple but novel free-choice task and simultaneous recording from individual neurons in nonhuman primate OFC. We found that, first, the observed sequences of choice behavior included periods of exceptionally long runs of each of two available options and periods of frequent switching. Neither a satiety-based mechanism nor a random selection process could explain the observed choice behavior. Second, OFC neurons encode important features of the choice behavior. These features include activity selective for exceptionally long runs of a given choice (stay selectivity) as well as activity selective for switches between choices (switch selectivity). These results suggest that OFC neural activity, in addition to encoding subjective values on a long timescale that is sensitive to satiety, also encodes a signal that fluctuates on a shorter timescale and thereby reflects some of the statistically improbable aspects of free-choice behavior. PMID:22423007
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Screening of various botanical extracts for antioxidant activity using DPPH free radical method.
Waqas, Muhammad Khurram; Saqib, Najam-Us; Rashid, Saeed-Ur; Shah, Pervaiz Akhtar; Akhtar, Naveed; Murtaza, Ghulam
2013-01-01
Aiming at the exploration of herbal use by society, crude extracts of the seeds of some commonly used medicinal plants (Vitis vinifera, Tamarindus indica and Glycin max) were screened for their free radical scavenging properties using ascorbic acid as standard antioxidant. Free radical scavenging activity was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical. The overall antioxidant activity of grape seeds (Vitis vinifera) was the strongest, followed in descending order by soybean (Glycin max) and tamarind (Tamarindus indica). The seeds extract of Vitis vinifera, Glycin max and Tamarindus indica showed 85.61%, 83.45% and 79.26%, DPPH scavenging activity respectively.
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Synthesis and Free Radical Scavenging Activity of New Hydroxybenzylidene Hydrazines.
Sersen, Frantisek; Gregan, Fridrich; Kotora, Peter; Kmetova, Jarmila; Filo, Juraj; Loos, Dusan; Gregan, Juraj
2017-05-29
Hydroxybenzylidene hydrazines exhibit a wide spectrum of biological activities. Here, we report synthesis and free radical scavenging activity of nine new N-(hydroxybenzylidene)-N'-[2,6-dinitro-4-(trifluoromethyl)]phenylhydrazines. The chemical structures of these compounds were confirmed by 1H-NMR, 13C-NMR, 19F-NMR, IR spectroscopy, LC-MS, and elemental analysis. The prepared compounds were tested for their activity to scavenge 2,2-diphenyl-1-picrylhydrazyl (DPPH), galvinoxyl radical (GOR), and 2,2'-azino-bis(3-ethylbenzothiazoline)-6-sulphonic acid (ABTS) radicals. The free radical scavenging activity expressed as SC50 values of these compounds varied in a wide range, from a strong to no radical scavenging effect. The most effective radical scavengers were hydroxybenzylidene hydrazines containing three hydroxyl groups in the benzylidene part of their molecules. The prepared compounds were also tested for their activity to inhibit photosynthetic electron transport in spinach chloroplasts. IC50 values of these compounds varied in wide range, from an intermediate to no inhibitory effect.
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Studies on free radical scavenging activity in Chinese seaweeds part I. Screening results
NASA Astrophysics Data System (ADS)
Yan, Xiao-Jun; Fang, Guo-Ming; Lou, Qing-Xiang
1999-09-01
Antioxidants have attracted the attention of researchers due to their beneficial effects as free radical scavengers. Application of a stable free radical named 1, 1-diphenyl-2-picrylhydrazyl(DPPH) to screen the free radical scavenging activity in 27 species of Chinese seaweed showed that 15 of them had significant activity in at least one of the organic solvent extracts. The most interesting seaweed species were Gelidium amansii, Gloiosiphonia capillaris, Polysiphonia urceolata, Sargassum kjellmanianum, Desmarestia viridis, and Rhodomela teres.
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Free Radical Scavenging Activity of Drops and Spray Containing Propolis-An EPR Examination.
Olczyk, Pawel; Komosinska-Vassev, Katarzyna; Ramos, Pawel; Mencner, Lukasz; Olczyk, Krystyna; Pilawa, Barbara
2017-01-13
The influence of heating at a temperature of 50 °C and UV-irradiation of propolis drops and spray on their free radical scavenging activity was determined. The kinetics of interactions of the propolis samples with DPPH free radicals was analyzed. Interactions of propolis drops and propolis spray with free radicals were examined by electron paramagnetic resonance spectroscopy. A spectrometer generating microwaves of 9.3 GHz frequency was used. The EPR spectra of the model DPPH free radicals were compared with the EPR spectra of DPPH in contact with the tested propolis samples. The antioxidative activity of propolis drops and propolis spray decreased after heating at the temperature of 50 °C. A UV-irradiated sample of propolis drops more weakly scavenged free radicals than an untreated sample. The antioxidative activity of propolis spray increased after UV-irradiation. The sample of propolis drops heated at the temperature of 50 °C quenched free radicals faster than the unheated sample. UV-irradiation weakly changed the kinetics of propolis drops or spray interactions with free radicals. EPR analysis indicated that propolis drops and spray should not be stored at a temperature of 50 °C. Propolis drops should not be exposed to UV-irradiation.
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Viscous forces are predominant in the zona pellucida mechanical resistance
NASA Astrophysics Data System (ADS)
Papi, Massimiliano; Maiorana, Alessandro; Douet, Cécile; Maulucci, Giuseppe; Parasassi, Tiziana; Brunelli, Roberto; Goudet, Ghylène; De Spirito, Marco
2013-01-01
The zona pellucida (ZP) is a multilayer glycoprotein spherical shell surrounding mammalian eggs. The ZP's mechanical response plays a crucial role in mammalian fertilization and is a parameter commonly adopted in "in vitro fertilization" to characterize the oocytes quality. While it is assumed that ZP mechanical response is purely elastic, here we prove that dissipative forces cannot be neglected. Physiologically, this evidence implies that an increase in the spermatozoa motility can induce dramatic changes on the ZP reaction force turning ZP shell in an impenetrable barrier leading to fertility impairments.
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Kovacs, K.; Horvath, E.; Singer, W.
1973-01-01
Numerous spironolactone bodies have been detected in the zona glomerulosa cells of the adrenal cortex of a 36-year-old spironolactone-treated woman whose non-tumorous right adrenal gland was removed surgically because of primary hyperaldosteronism. Electron microscopy revealed spherical laminated whorls which consisted of a central core composed of an amorphous electron-dense material surrounded by numerous smooth-walled concentric membranes. Continuous with and deriving from the endoplasmic reticulum, they were present in viable cells and were not associated with ultrastructural features indicating cellular injury. Cytoplasmic inclusions similar to spironolactone bodies can be detected in other organs after the administration of various compounds. Thus, they can be regarded as neither specific to spironolactone treatment nor exclusively inducible in the zona glomerulosa of the adrenal cortex. Images PMID:4131694
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Free radical-scavenging activities of Crataegus monogyna extracts.
Bernatoniene, Jurga; Masteikova, Rūta; Majiene, Daiva; Savickas, Arūnas; Kevelaitis, Egidijus; Bernatoniene, Rūta; Dvorácková, Katerina; Civinskiene, Genuvaite; Lekas, Raimundas; Vitkevicius, Konradas; Peciūra, Rimantas
2008-01-01
The aim of this study was to investigate antiradical activity of aqueous and ethanolic hawthorn fruit extracts, their flavonoids, and flavonoid combinations. Total amount of phenolic compounds and the constituents of flavonoids were determined using a high-performance liquid chromatography. The antioxidant activity of Crataegus monogyna extracts and flavonoids (chlorogenic acid, hyperoside, rutin, quercetin, vitexin-2O-rhamnoside, epicatechin, catechin, and procyanidin B(2)) quantitatively was determined using the method of spectrophotometry (diphenyl-1-picrylhydrazyl (DPPH.) radical scavenging assay and 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid)(ABTS.+) radical cation decolorization assay). The level of tyrosine nitration inhibition was determined using a high-performance liquid chromatography. Ethanolic hawthorn fruit extract contained 182+/-4 mg/100 mL phenolic compounds, i.e. threefold more, as compared to aqueous extract. The antioxidant activity according to DPPH. reduction in the ethanolic extracts was higher 2.3 times (P<0.05). The ABTS.+ technique showed that the effect of ethanolic extracts was by 2.5 times stronger than that of aqueous extracts. Tyrosine nitration inhibition test showed that the effect of ethanolic extracts was by 1.4 times stronger than that of aqueous extracts. The investigation of the antiradical activity of the active constituents in aqueous and ethanolic extracts revealed that epicatechin and catechin contribute to radical-scavenging properties more than other components. Procyanidin B(2) only insignificantly influenced the antiradical activity of the extracts. Both aqueous and ethanolic hawthorn extracts had antiradical activity, but ethanolic extract had stronger free radical-scavenging properties, compared to the aqueous extract. The antioxidant activity of the studied preparations was mostly conditioned by epicatechin and catechin. The individual constituents of both extracts had weaker free radical
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Li, Lu-jun; Yu, Li-juan; Li, Yan-ci; Liu, Meng-yuan; Wu, Zheng-zhi
2015-04-01
This study was carried out to evaluate the anti-inflammatory and free radical scavenging activities of flavans from flex centrochinensis S. Y. Hu in vitro and their structure-activity relationship. LPS-stimulated RAW 264.7 macrophage was used as inflammatory model. MTT assay for cell availability, Griess reaction for nitric oxide (NO) production, the content of TNF-alpha, IL-1beta, IL-6 and PGE, were detected with ELISA kits; DPPH, superoxide anion and hydroxyl free radicals scavenging activities were also investigated. According to the result, all flavans tested exhibited anti-inflammatory effect in different levels. Among them, compounds 1, 3, 4 and 6 showed potent anti-inflammatory effect through the inhibition of NO, TNF-alpha, IL-lp and IL-6, of which 1 was the most effective inhibitor, however, 2 and 5 were relatively weak or inactive. The order of free radical scavenging activities was similar to that of anti-inflammatory activities. Therefore, these results suggest that 3, 4 and 6, especially of 1, were,in part responsible for the anti-inflammatory and free radical scavenging activity of Ilex centrochinensis. Hydroxyl group at 4'-position of B-ring plays an important role in the anti-inflammatory and free radical scavenging capacities.
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A comparison of muscle activation between a Smith machine and free weight bench press.
Schick, Evan E; Coburn, Jared W; Brown, Lee E; Judelson, Daniel A; Khamoui, Andy V; Tran, Tai T; Uribe, Brandon P
2010-03-01
The bench press exercise exists in multiple forms including the machine and free weight bench press. It is not clear though how each mode differs in its effect on muscle activation. The purpose of this study was to compare muscle activation of the anterior deltoid, medial deltoid, and pectoralis major during a Smith machine and free weight bench press at lower (70% 1 repetition maximum [1RM]) and higher (90% 1RM) intensities. Normalized electromyography amplitude values were used during the concentric phase of the bench press to compare muscle activity between a free weight and Smith machine bench press. Participants were classified as either experienced or inexperienced bench pressers. Two testing sessions were used, each of which entailed either all free weight or all Smith machine testing. In each testing session, each participant's 1RM was established followed by 2 repetitions at 70% of 1RM and 2 repetitions at 90% of 1RM. Results indicated greater activation of the medial deltoid on the free weight bench press than on the Smith machine bench press. Also, there was greater muscle activation at the 90% 1RM load than at the 70% 1RM load. The results of this study suggest that strength coaches should consider choosing the free weight bench press over the Smith machine bench press because of its potential for greater upper-body muscular development.
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Non-Formal Education in Free Time: Leisure- or Work-Orientated Activity?
ERIC Educational Resources Information Center
Thoidis, Ioannis; Pnevmatikos, Dimitrios
2014-01-01
This article deals with the relationship between adults' free time and further education. More specifically, the paper addresses the question of whether there are similarities and analogies between the leisure time that adults dedicate to non-formal educational activities and free time per se. A structured questionnaire was used to examine the…
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Wahyuningrum, Retno; Utami, Pri Iswati; Dhiani, Binar Asrining; Kumalasari, Malikhah; Kusumawardani, Rizka Sari
2016-11-01
Purwoceng ( Pimpinella alpina Molk) is a traditional medicinal plant used for its aphrodisiac values. This plant was originated Dieng Plateu, Central Java, Indonesia. Purwoceng has been reported to contain steroid, flavonoids, glycoside, saponins, tannins, and phenolic. Based on secondary metabolite compounds of Purwoceng herbs, a research need to be done to determine the other potential free radicals scavenger and antibacterial activities of Purwoceng. The objectives of this research are to screen the potential free radicals scavenger activity of in vitro using DPPH (1,1 diphenyl-2-picryl-hydrazil) radicals and NO• (nitric oxide) radicals, and antibacterial activity of Purwoceng. The extraction is done by a maceration method with petroleum ether, ethyl acetate, and ethanol solvent, respectively. Free radicals scavenger test was performed using DPPH radicals and NO• radicals, while antibacterial activity screening was performed using agar diffusion test. The results showed that ethyl acetate extract of Purwoceng has free radical scavenger activity with IC50 53.07 ppm lower than butylated hydroxytoluene. Ethyl acetate extract and ethanol extract of Purwoceng have antibacterial activity against Staphyloccus aureus , Escherichia coli , and MG42 bacterial isolate.
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NASA Astrophysics Data System (ADS)
Zeng, Mingyong; Xiao, Feng; Zhao, Yuanhui; Liu, Zunying; Li, Bafang; Dong, Shiyuan
2007-07-01
Gelatin from the sea cucumber (Paracaudina chinens var.) was hydrolyzed by bromelain and the hydrolysate was found to have a high free radical scavenging activity. The hydrolysate was fractionated through an ultrafiltration membrane with 5 kDa molecular weight cutoff (MWCO). The portion (less than 5 kDa) was further separated by Sephadex G-25. The active peak was collected and assayed for free radical scavenging activity. The scavenging rates for superoxide anion radicals (O2·-) and hydroxyl radicals (·OH) of the fraction with the highest activity were 29.02% and 75.41%, respectively. A rabbit liver mitochondrial free radical damage model was adopted to study the free radical scavenging activity of the fraction. The results showed that the sea cucumber gelatin hydrolysate can prevent the damage of rabbit liver and mitochondria.
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Student Organizations--FBLA Projects and Activities Relating to Free Enterprise.
ERIC Educational Resources Information Center
Western Kentucky Univ., Bowling Green.
This guide for Future Business Leaders of America and Phi Beta Lambda chapters describes 25 economic awareness projects/activities to create awareness of the free enterprise economic system. Introductory materials include suggestions for project planning and management and a worksheet for planning activities and projects. The projects/activities…
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Murphy, James G; Barnett, Nancy P; Colby, Suzanne M
2006-08-01
College student alcohol abuse remains a significant public health problem, and there is a need for theory-driven and empirically based models to guide prevention efforts. Behavioral theories of choice assume that the decision to consume alcohol is influenced by the relative value of alcohol versus other available activities. In the present study, a sample of college student drinkers (N=108; 56% female, 44% male) who had previously completed a mandatory alcohol intervention completed a measure of alcohol-related and alcohol-free activity participation and enjoyment. The goals of the study were to examine the influence of drinking quantity and contextual variables on activity enjoyment and to identify enjoyable alcohol-free activities that take place on evenings when students might otherwise be drinking. Overall, students found alcohol-related activities more enjoyable than alcohol-free activities, and drinking quantity was positively related to enjoyment. However, alcohol-free activities such as watching movies, going to the theater or museums, going to bars or parties, hanging out with friends, eating at restaurants, and engaging in creative activity were generally as enjoyable as drinking. Alcohol-free activities that included peers or dates were more enjoyable than solitary activities. Men were less likely to engage in alcohol-free activities that included peers and reported less enjoyment related to alcohol-free activities than did women. Further research is required to identify procedures for increasing participation in alcohol-free activities and to determine whether increased alcohol-free activity participation results in decreased alcohol consumption.
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Free-energy landscape of ion-channel voltage-sensor–domain activation
Delemotte, Lucie; Kasimova, Marina A.; Klein, Michael L.; Tarek, Mounir; Carnevale, Vincenzo
2015-01-01
Voltage sensor domains (VSDs) are membrane-bound protein modules that confer voltage sensitivity to membrane proteins. VSDs sense changes in the transmembrane voltage and convert the electrical signal into a conformational change called activation. Activation involves a reorganization of the membrane protein charges that is detected experimentally as transient currents. These so-called gating currents have been investigated extensively within the theoretical framework of so-called discrete-state Markov models (DMMs), whereby activation is conceptualized as a series of transitions across a discrete set of states. Historically, the interpretation of DMM transition rates in terms of transition state theory has been instrumental in shaping our view of the activation process, whose free-energy profile is currently envisioned as composed of a few local minima separated by steep barriers. Here we use atomistic level modeling and well-tempered metadynamics to calculate the configurational free energy along a single transition from first principles. We show that this transition is intrinsically multidimensional and described by a rough free-energy landscape. Remarkably, a coarse-grained description of the system, based on the use of the gating charge as reaction coordinate, reveals a smooth profile with a single barrier, consistent with phenomenological models. Our results bridge the gap between microscopic and macroscopic descriptions of activation dynamics and show that choosing the gating charge as reaction coordinate masks the topological complexity of the network of microstates participating in the transition. Importantly, full characterization of the latter is a prerequisite to rationalize modulation of this process by lipids, toxins, drugs, and genetic mutations. PMID:25535341
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Free-energy landscape of ion-channel voltage-sensor-domain activation.
Delemotte, Lucie; Kasimova, Marina A; Klein, Michael L; Tarek, Mounir; Carnevale, Vincenzo
2015-01-06
Voltage sensor domains (VSDs) are membrane-bound protein modules that confer voltage sensitivity to membrane proteins. VSDs sense changes in the transmembrane voltage and convert the electrical signal into a conformational change called activation. Activation involves a reorganization of the membrane protein charges that is detected experimentally as transient currents. These so-called gating currents have been investigated extensively within the theoretical framework of so-called discrete-state Markov models (DMMs), whereby activation is conceptualized as a series of transitions across a discrete set of states. Historically, the interpretation of DMM transition rates in terms of transition state theory has been instrumental in shaping our view of the activation process, whose free-energy profile is currently envisioned as composed of a few local minima separated by steep barriers. Here we use atomistic level modeling and well-tempered metadynamics to calculate the configurational free energy along a single transition from first principles. We show that this transition is intrinsically multidimensional and described by a rough free-energy landscape. Remarkably, a coarse-grained description of the system, based on the use of the gating charge as reaction coordinate, reveals a smooth profile with a single barrier, consistent with phenomenological models. Our results bridge the gap between microscopic and macroscopic descriptions of activation dynamics and show that choosing the gating charge as reaction coordinate masks the topological complexity of the network of microstates participating in the transition. Importantly, full characterization of the latter is a prerequisite to rationalize modulation of this process by lipids, toxins, drugs, and genetic mutations.
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Toddler activity intensity during indoor free-play: stand and watch.
Fees, Bronwyn S; Fischer, Elexa; Haar, Sherry; Crowe, Linda K
2015-01-01
Movement patterns among toddlers (16-36 months) differ from other early developmental periods; toddlers practice coordination, balance, and control. Toddler care environments may afford repetition of these emerging skills. This study examined intensity and type of movements during free-play indoors in child care among toddlers. A convenience sample (n, 41; mean, 26.5 months) was observed for intensity of physical activity (PA), motor activity type, activity context, and teacher prompts in center-based care using a modified version of the Observational System for Recording Physical Activity for Children-Preschool. The most frequent PA intensity level was sedentary with limb movement. No significant gender differences emerged. Standing, sitting/squatting, and walking were the most frequent activity types. Dominant activity contexts included fine motor manipulative, self-care, and onlooking. Logistic regression results indicated that onlooking significantly decreased the odds of moderate to vigorous PA. Teachers offered few prompts to increase PA. Toddlers demonstrate predominantly sedentary behaviors during free-play. Further observational research across the entire day is warranted to accurately assess intensity and teacher's support for moderate to vigorous PA. Copyright © 2015 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.
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Bergenin Content and Free Radical Scavenging Activity of Bergenia Extracts. .
Hendrychová, Helena; Martin, Jan; Tůmová, Lenka; Kočevar-Glavač, Nina
2015-07-01
Our research was focused on the evaluation of bergenin content and free radical scavenging activity of extracts prepared from three different species of Bergenia - B. crassifolia (L.) Fritsch., B. ciliata (Haw.) Sternb. and B. x ornata Stein. collected during different seasons. Using an HPLC method, the highest total amount of bergenin was revealed in the leaves of B. x ornata and B. crassifolia (4.9 - 5.1 mg x g(-1)). Free radical scavenging power was determined by two methods--FRAP and NADH. The best free radical scavengers were B. crassifolia (FRAP: 6.7 - 15.9 mg GAE. 100g(-1); NADH: 20.3 - 50.9%) and B. ornata (FRAP: 13.7 - 15.2 mg GAE. 100g(-1); NADH: 29.3 - 31.1%). The lowest content of bergenin and the weakest radical scavenger was B. ciliata (bergenin: 3.1 mg x g(-1); FRAP: 5.5 - 11.0 mg GAE.100g(-1); NADH: 23.2 - 25.6%). The presence of a large percentage of bergenin is responsible for the radical scavenging activity, as shown by the results from the FRAP and NADH assays. Significant, positive correlation was found between bergenin content and radical scavenging activity in both methods.
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Alkali silica reaction (ASR) in cement free alkali activated sustainable concrete.
DOT National Transportation Integrated Search
2016-12-19
This report summarizes the findings of an experimental evaluation into alkali silica : reaction (ASR) in cement free alkali-activated slag and fly ash binder concrete. The : susceptibility of alkali-activated fly ash and slag concrete binders to dele...
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You and Me Tobacco Free: Children's Activities in Tobacco Awareness.
ERIC Educational Resources Information Center
Scheer, Judith K.
This booklet is part of the "Children's Activity Series," a set of four supplemental teaching resources that promote awareness about health, family life, and cultural diversity for children in kindergarten through third grade. The booklet presents seven activities to teach young children in kindergarten through third grade to remain tobacco free.…
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NASA Astrophysics Data System (ADS)
Xereas, George; Chodavarapu, Vamsy P.
2014-03-01
Frequency references are used in almost every modern electronic device including mobile phones, personal computers, and scientific and medical instrumentation. With modern consumer mobile devices imposing stringent requirements of low cost, low complexity, compact system integration and low power consumption, there has been significant interest to develop batch-manufactured MEMS resonators. An important challenge for MEMS resonators is to match the frequency and temperature stability of quartz resonators. We present 1MHz and 20MHz temperature compensated Free-Free beam MEMS resonators developed using PolyMUMPS, which is a commercial multi-user process available from MEMSCAP. We introduce a novel temperature compensation technique that enables high frequency stability over a wide temperature range. We used three strategies: passive compensation by using a structural gold (Au) layer on the resonator, active compensation through using a heater element, and a Free-Free beam design that minimizes the effects of thermal mismatch between the vibrating structure and the substrate. Detailed electro-mechanical simulations were performed to evaluate the frequency response and Quality Factor (Q). Specifically, for the 20MHz device, a Q of 10,000 was obtained for the passive compensated design. Finite Element Modeling (FEM) simulations were used to evaluate the Temperature Coefficient of frequency (TCf) of the resonators between -50°C and 125°C which yielded +0.638 ppm/°C for the active compensated, compared to -1.66 ppm/°C for the passively compensated design and -8.48 ppm/°C for uncompensated design for the 20MHz device. Electro-thermo-mechanical simulations showed that the heater element was capable of increasing the temperature of the resonators by approximately 53°C with an applied voltage of 10V and power consumption of 8.42 mW.
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Ferrer, Marvin; Rodriguez, Hilma; Zara, Lindsay; Yu, Yang; Xu, Wei; Oko, Richard
2012-09-01
Sperm-zona pellucida (ZP) penetration during fertilization is a process that most likely involves enzymatic digestion of this extracellular coat by spermatozoa. Since the inner acrosomal membrane (IAM) is the leading edge of spermatozoa during penetration and proteins required for secondary binding of sperm to the zona are present on it, the IAM is the likely location of these enzymes. The objectives of this study were to identify and characterize proteinases present on the IAM, confirm their localization and provide evidence for their role in fertilization. Gelatin zymography of detergent extracts of the IAM revealed bands of enzymatic activity identified as serine and matrix metallo-proteinases (MMPs). Specific inhibitors to MMPs revealed that MMP activity was due to MMP2. Immunoblotting determined that the serine protease activity on the zymogram was due to acrosin and also confirmed the MMP2 activity. Immunogold labeling of spermatozoa at the electron microscope level showed that acrosin and MMP2 were confined to the apical and principal segments of the acrosome in association with the IAM, confirming our IAM isolation technique. Immunohistochemical examination of acrosin and MMP2 during spermiogenesis showed that both proteins originate in the acrosomic granule during the Golgi phase and later redistribute to the acrosomal membrane. Anti-MMP2 antibodies and inhibitors incorporated into in vitro fertilization media significantly decreased fertilization rates. This is the first study to demonstrate that MMP2 and acrosin are associated with the IAM and introduces the possibility of their cooperation in enzymatic digestion of the ZP during penetration.
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Effects of replacing free weights with elastic band resistance in squats on trunk muscle activation.
Saeterbakken, Atle H; Andersen, Vidar; Kolnes, Maria K; Fimland, Marius S
2014-11-01
The purpose of this study was to assess the effects of adding elastic bands to free-weight squats on the neuromuscular activation of core muscles. Twenty-five resistance trained women with 4.6 ± 2.1 years of resistance training experience participated in the study. In randomized order, the participants performed 6 repetition maximum in free-weight squats, with and without elastic bands (i.e., matched relative intensity between exercises). During free-weight squats with elastic bands, some of the free weights were replaced with 2 elastic bands attached to the lowest part of the squat rack. Surface electromyography (EMG) activity was measured from the erector spinae, external oblique, and rectus abdominis, whereas a linear encoder measured the vertical displacement. The EMG activities were compared between the 2 lifting modalities for the whole repetition and separately for the eccentric, concentric, and upper and lower eccentric and concentric phases. In the upper (greatest stretch of the elastic band), middle, and lower positions in squats with elastic bands, the resistance values were approximately 117, 105, and 93% of the free weight-only trial. Similar EMG activities were observed for the 2 lifting modalities for the erector spinae (p = 0.112-0.782), external oblique (p = 0.225-0.977), and rectus abdominis (p = 0.315-0.729) in all analyzed phases. In conclusion, there were no effects on the muscle activity of trunk muscles of substituting some resistance from free weights with elastic bands in the free-weight squat.
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Federal Register 2010, 2011, 2012, 2013, 2014
2012-12-26
... Activities: Declaration for Free Entry of Unaccompanied Articles AGENCY: U.S. Customs and Border Protection... collection requirement concerning the Declaration for Free Entry of Unaccompanied Articles (Form 3299). This... concerning the following information collection: Title: Declaration for Free Entry of Unaccompanied Articles...
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Energy Cost of Free-Play Activities in 10- to 11-Year-Old Children.
Mackintosh, Kelly Alexandra; Ridley, Kate; Stratton, Gareth; Ridgers, Nicola D
2016-06-01
This study sought to ascertain the energy expenditure (EE) associated with different sedentary and physically active free-play activities in primary school-aged children. Twenty-eight children (13 boys; 11.4 ± 0.3 years; 1.45 ± 0.09 m; 20.0 ± 4.7 kg∙m-2) from 1 primary school in Northwest England engaged in 6 activities representative of children's play for 10 minutes (drawing, watching a DVD, playground games and free-choice) and 5 minutes (self-paced walking and jogging), with 5 minutes rest between each activity. Gas exchange variables were measured throughout. Resting energy expenditure was measured during 15 minutes of supine rest. Child (Schofield-predicted) MET values for watching a DVD, self-paced jogging and playing reaction ball were significantly higher for girls (P < .05). Utilizing a field-based protocol to examine children's free-living behaviors, these data contribute to the scarcity of information concerning children's EE during play to update the Compendium of Energy Expenditures for Youth.
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Holt, Nicholas L; Neely, Kacey C; Spence, John C; Carson, Valerie; Pynn, Shannon R; Boyd, Kassi A; Ingstrup, Meghan; Robinson, Zac
2016-08-19
Children's engagement in active free play has declined across recent generations. Therefore, the purpose of this study was to examine perceptions of intergenerational changes in active free play among families from rural areas. We addressed two research questions: (1) How has active free play changed across three generations? (2) What suggestions do participants have for reviving active free play? Data were collected via 49 individual interviews with members of 16 families (15 grandparents, 16 parents, and 18 children) residing in rural areas/small towns in the Province of Alberta (Canada). Interview recordings were transcribed verbatim and subjected to thematic analysis guided by an ecological framework of active free play. Factors that depicted the changing nature of active free play were coded in the themes of less imagination/more technology, safety concerns, surveillance, other children to play with, purposeful physical activity, play spaces/organized activities, and the good parenting ideal. Suggestions for reviving active free play were coded in the themes of enhance facilities to keep kids entertained, provide more opportunities for supervised play, create more community events, and decrease use of technology. These results reinforce the need to consider multiple levels of social ecology in the study of active free play, and highlight the importance of community-based initiatives to revive active free play in ways that are consistent with contemporary notions of good parenting.
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UHF wearable battery free sensor module for activity and falling detection.
Nam Trung Dang; Thang Viet Tran; Wan-Young Chung
2016-08-01
Falling is one of the most serious medical and social problems in aging population. Therefore taking care of the elderly by detecting activity and falling for preventing and mitigating the injuries caused by falls needs to be concerned. This study proposes a wearable, wireless, battery free ultra-high frequency (UHF) smart sensor tag module for falling and activity detection. The proposed tag is powered by UHF RF wave from reader and read by a standard UHF Electronic Product Code (EPC) Class-1 Generation-2 reader. The battery free sensor module could improve the wearability of the wireless device. The combination of accelerometer signal and received signal strength indication (RSSI) from a reader in the passive smart sensor tag detect the activity and falling of the elderly very successfully. The fabricated smart sensor tag module has an operating range of up to 2.5m and conducting in real-time activity and falling detection.
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McBride, Devin W.; Rodgers, Victor G. J.
2013-01-01
The activity coefficient is largely considered an empirical parameter that was traditionally introduced to correct the non-ideality observed in thermodynamic systems such as osmotic pressure. Here, the activity coefficient of free-solvent is related to physically realistic parameters and a mathematical expression is developed to directly predict the activity coefficients of free-solvent, for aqueous protein solutions up to near-saturation concentrations. The model is based on the free-solvent model, which has previously been shown to provide excellent prediction of the osmotic pressure of concentrated and crowded globular proteins in aqueous solutions up to near-saturation concentrations. Thus, this model uses only the independently determined, physically realizable quantities: mole fraction, solvent accessible surface area, and ion binding, in its prediction. Predictions are presented for the activity coefficients of free-solvent for near-saturated protein solutions containing either bovine serum albumin or hemoglobin. As a verification step, the predictability of the model for the activity coefficient of sucrose solutions was evaluated. The predicted activity coefficients of free-solvent are compared to the calculated activity coefficients of free-solvent based on osmotic pressure data. It is observed that the predicted activity coefficients are increasingly dependent on the solute-solvent parameters as the protein concentration increases to near-saturation concentrations. PMID:24324733
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Hou, S T; Ma, A; Jones, R; Hall, L
1996-10-01
The rat sperm surface antigen, 2B1, that has been proposed to play a key role in sperm adhesion to the zona pellucida, has been cloned and its entire cDNA sequenced. Northern blot analysis indicates that 2B1 is encoded by a 2.2-kb RNA transcript that is abundantly expressed in the testis. The deduced protein sequence contains 512 amino-acid residues with a strong candidate signal sequence and C-terminal transmembrane domain. Data base searches reveal a high degree of sequence similarity to guinea pig, rabbit, monkey, and human PH20 sperm surface antigens, and a lower degree of similarity to honey bee and whiteface hornet venom hyaluronidases. Rat 2B1 antigen also possesses hyaluronidase activity, suggesting that it is a bifunctional protein with putative roles in the dispersion of cumulus oophorus cells as well as zona adhesion. However, while it would appear that 2B1 is the rat homologue of the guinea pig PH20 antigen, they differ in a number of important biochemical respects (including their mode of attachment to the sperm membrane and distribution between soluble and membrane-bound fractions), as well as in their localization on the sperm membrane. Expression of regions of the 2B1 protein in recombinant bacterial cells has allowed a preliminary mapping of the 2B1 epitope, and has provided more definitive information on the endoproteolytic processing of 2B1 during epididymal transit.
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Antioxidant activity of commercial buckwheat flours and their free and bound phenolic compositions
USDA-ARS?s Scientific Manuscript database
Buckwheat flours (Whole, Farinetta, Supreme, and Fancy) were investigated for their compositions, free and bound phenolic contents, antioxidant activities, and flavonoid contents using spectrophotometer and LC-ESI-IT- MS (LC-MS). Farinetta flour contained the highest oil, protein, and free and boun...
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Garratt, Luke W; Sutanto, Erika N; Ling, Kak-Ming; Looi, Kevin; Iosifidis, Thomas; Martinovich, Kelly M; Shaw, Nicole C; Kicic-Starcevich, Elizabeth; Knight, Darryl A; Ranganathan, Sarath; Stick, Stephen M; Kicic, Anthony
2015-08-01
Neutrophil elastase is the most significant predictor of bronchiectasis in early-life cystic fibrosis; however, the causal link between neutrophil elastase and airway damage is not well understood. Matrix metalloproteinases (MMPs) play a crucial role in extracellular matrix modelling and are activated by neutrophil elastase. The aim of this study was to assess if MMP activation positively correlates with neutrophil elastase activity, disease severity and bronchiectasis in young children with cystic fibrosis.Total MMP-1, MMP-2, MMP-7, MMP-9, tissue inhibitor of metalloproteinase (TIMP)-2 and TIMP-1 levels were measured in bronchoalveolar lavage fluid collected from young children with cystic fibrosis during annual clinical assessment. Active/pro-enzyme ratio of MMP-9 was determined by gelatin zymography. Annual chest computed tomography imaging was scored for bronchiectasis.A higher MMP-9/TIMP-1 ratio was associated with free neutrophil elastase activity. In contrast, MMP-2/TIMP-2 ratio decreased and MMP-1 and MMP-7 were not detected in the majority of samples. Ratio of active/pro-enzyme MMP-9 was also higher in the presence of free neutrophil elastase activity, but not infection. Across the study cohort, both MMP-9/TIMP-1 and active MMP-9 were associated with progression of bronchiectasis.Both MMP-9/TIMP-1 and active MMP-9 increased with free neutrophil elastase and were associated with bronchiectasis, further demonstrating that free neutrophil elastase activity should be considered an important precursor to cystic fibrosis structural disease. Copyright ©ERS 2015.
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Developmental kinetics of pig embryos by parthenogenetic activation or by handmade cloning.
Li, J; Li, R; Liu, Y; Villemoes, K; Purup, S; Callesen, H
2013-10-01
The developmental kinetics of pig embryos produced by parthenogenetic activation without (PAZF) or with (PAZI) zona pellucida or by handmade cloning (HMC) was compared by time-lapse videography. After cumulus cell removal, the matured oocytes were either left zona intact (PAZI) or were made zona free by pronase digestion (PAZF) before they were activated (PA). Other matured oocytes were used for HMC based on foetal fibroblast cells. On Day 0 (day of PA or reconstruction), the embryos were cultured for 7 days in vitro in our time-lapse system. Pictures were taken every 30 min, and afterwards, each cell cycle was identified for each embryo to be analysed. Results showed that the PA embryos (both PAZF and PAZI) had shorter first cell cycle compared with HMC (17.4. 17.8 vs 23.6 h), but had a longer time length from four cell to morula stages (57.9, 53.8 vs 44.9 h). However, at the second cell cycle, PAZF embryos needed shorter time, while PAZI embryos had similar time length as HMC embryos, and both were longer than PAZF (23.4, 24.8 vs 14.6 h). Both PAZF and PAZI embryos used similar time to reach the blastocyst stage, and this was later than HMC embryos. In addition, when all of these embryos were grouped into viable (developed to blastocysts) and non-viable (not developed to blastocysts), the only difference in the time length was observed on the first cell cycle (18.6 vs 24.5 h), but not on the later cell cycles. In conclusion, our results not only give detailed information regarding the time schedule of in vitro-handled pig embryos, but also indicate that the first cell cycle could be used as a selecting marker for embryo viability. However, to evaluate the effect of the produced techniques, the whole time schedule of the pre-implantation developmental kinetics should be observed. © 2013 Blackwell Verlag GmbH.
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Tanihara, Fuminori; Nakai, Michiko; Men, Nguyen Thi; Kato, Noriko; Kaneko, Hiroyuki; Noguchi, Junko; Otoi, Takeshige; Kikuchi, Kazuhiro
2014-04-01
The zona pellucida (ZP) is considered to play important roles in the prevention of polyspermy in mammalian oocytes. However, in pigs we have shown that the presence of the ZP accelerates sperm penetration into the ooplasm during in vitro fertilization (IVF). In the present study, we investigated the effects of the ZP on sperm binding, acrosomal status, and functional exposure of IZUMO, a critical factor involved in sperm-egg fusion, during IVF in pigs. We evaluated the numbers and acrosomal statuses of sperm binding to the ZP and oolemma, and being present in the ZP and perivitelline space (PVS) using ZP-intact and ZP-free oocytes. More sperm bound to the ZP than to the oolemma. The average number of sperm present in the PVS was 0.44-0.51 per oocyte, and all sperm had lost their acrosomes. The proportion of sperm that were immunopositive for anti-IZUMO antibody was significantly higher after they were passing or had passed through the ZP. Furthermore, addition of anti-IZUMO antibody to the fertilization medium significantly inhibited the penetration of sperm into ZP-free oocytes. These results suggest that, in pigs, the ZP induces the acrosome reaction, which is associated with the functional exposure of IZUMO, resulting in completion of fertilization. © 2014 Japanese Society of Animal Science.
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Knoebl, Iris, Michael J. Hemmer and Nancy D. Denslow. 2004. Induction of Zona Radiata Proteins and Vitellogenins in Estradiol and Nonylphenol Exposed Male Sheepshead Minnows (Cyprinodon variegatus). Mar. Environ. Res. 58(2-5):547-551. (ERL,GB X1059).
Several genes normall... -
Touroutoglou, Alexandra; Bickart, Kevin C; Barrett, Lisa Feldman; Dickerson, Bradford C
2014-10-01
Individual differences in the intensity of feelings of arousal while viewing emotional pictures have been associated with the magnitude of task-evoked blood-oxygen dependent (BOLD) response in the amygdala. Recently, we reported that individual differences in feelings of arousal are associated with task-free (resting state) connectivity within the salience network. There has not yet been an investigation of whether these two types of functional magnetic resonance imaging (MRI) measures are redundant or independent in their relationships to behavior. Here we tested the hypothesis that a combination of task-evoked amygdala activation and task-free amygdala connectivity within the salience network relate to individual differences in feelings of arousal while viewing of negatively potent images. In 25 young adults, results revealed that greater task-evoked amygdala activation and stronger task-free amygdala connectivity within the salience network each contributed independently to feelings of arousal, predicting a total of 45% of its variance. Individuals who had both increased task-evoked amygdala activation and stronger task-free amygdala connectivity within the salience network had the most heightened levels of arousal. Task-evoked amygdala activation and task-free amygdala connectivity within the salience network were not related to each other, suggesting that resting-state and task-evoked dynamic brain imaging measures may provide independent and complementary information about affective experience, and likely other kinds of behaviors as well. Copyright © 2014 Wiley Periodicals, Inc.
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Minakata, Daisuke; Crittenden, John
2011-04-15
The hydroxyl radical (HO(•)) is a strong oxidant that reacts with electron-rich sites on organic compounds and initiates complex radical chain reactions in aqueous phase advanced oxidation processes (AOPs). Computer based kinetic modeling requires a reaction pathway generator and predictions of associated reaction rate constants. Previously, we reported a reaction pathway generator that can enumerate the most important elementary reactions for aliphatic compounds. For the reaction rate constant predictor, we develop linear free energy relationships (LFERs) between aqueous phase literature-reported HO(•) reaction rate constants and theoretically calculated free energies of activation for H-atom abstraction from a C-H bond and HO(•) addition to alkenes. The theoretical method uses ab initio quantum mechanical calculations, Gaussian 1-3, for gas phase reactions and a solvation method, COSMO-RS theory, to estimate the impact of water. Theoretically calculated free energies of activation are found to be within approximately ±3 kcal/mol of experimental values. Considering errors that arise from quantum mechanical calculations and experiments, this should be within the acceptable errors. The established LFERs are used to predict the HO(•) reaction rate constants within a factor of 5 from the experimental values. This approach may be applied to other reaction mechanisms to establish a library of rate constant predictions for kinetic modeling of AOPs.
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Physical Activity in High School during "Free-Time" Periods
ERIC Educational Resources Information Center
Silva, Pedro; Sousa, Michael; Sá, Carla; Ribeiro, José; Mota, Jorge
2015-01-01
The purpose of this study was to examine youth physical activity (PA) in free-time periods during high school days and their contribution to total PA. Differences in terms of sex, age, body mass index and school level were assessed in a sample of Portuguese adolescents. Participants totalled 213 (135 girls), aged 14.6 ± 1.7, from two different…
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Buehler, Paul W.; Butt, Omer I.; D'Agnillo, Felice, E-mail: felice.dagnillo@fda.hhs.gov
Highlights: {yields} Toxicological implications associated with the use of NaNO{sub 2} therapy to treat systemic cell-free Hb exposure are not well-defined. {yields} Systemic Hb exposure followed by NaNO{sub 2} infusion induces acute CNS toxicities in guinea pigs. {yields} These CNS effects were not reproduced by the infusion of cell-free Hb or NaNO{sub 2} alone. {yields} NaNO{sub 2}-mediated oxidation of cell-free Hb may play a causative role in the observed CNS changes. -- Abstract: Systemic cell-free hemoglobin (Hb) released via hemolysis disrupts vascular homeostasis, in part, through the scavenging of nitric oxide (NO). Sodium nitrite (NaNO{sub 2}) therapy can attenuate themore » hypertensive effects of Hb. However, the chemical reactivity of NaNO{sub 2} with Hb may enhance heme- or iron-mediated toxicities. Here, we investigate the effect of NaNO{sub 2} on the central nervous system (CNS) in guinea pigs exposed to systemic cell-free Hb. Intravascular infusion of NaNO{sub 2}, at doses sufficient to alleviate Hb-mediated blood pressure changes, reduced the expression of occludin, but not zona occludens-1 (ZO-1) or claudin-5, in cerebral tight junctions 4 h after Hb infusion. This was accompanied by increased perivascular heme oxygenase-1 expression, neuronal iron deposition, increased astrocyte and microglial activation, and reduced expression of neuron-specific nuclear protein (NeuN). These CNS changes were not observed in animals treated with Hb or NaNO{sub 2} alone. Taken together, these findings suggest that the use of nitrite salts to treat systemic Hb exposure may promote acute CNS toxicity.« less
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Li, Jia-Ling; Salam, Nimaichand; Wang, Pan-Deng; Chen, Lin-Xing; Jiao, Jian-Yu; Li, Xin; Xian, Wen-Dong; Han, Ming-Xian; Fang, Bao-Zhu; Mou, Xiao-Zhen; Li, Wen-Jun
2018-03-16
Bacterioplankton are the major driving force for biogeochemical cycles in estuarine ecosystems, but the communities that mediate these processes are largely unexplored. We sampled in the Pearl River Estuary (PRE) to examine potential differences in the taxonomic composition of resident (DNA-based) and active (RNA-based) bacterioplankton communities in free-living and particle-associated fractions. MiSeq sequencing data showed that the overall bacterial diversity in particle-associated fractions was higher than in free-living communities. Further in-depth analyses of the sequences revealed a positive correlation between resident and active bacterioplankton communities for the particle-associated fraction but not in the free-living fraction. However, a large overlapping of OTUs between free-living and particle-associated communities in PRE suggested that the two fractions may be actively exchanged. We also observed that the positive correlation between resident and active communities is more prominent among the abundant OTUs (relative abundance > 0.2%). Further, the results from the present study indicated that low-abundance bacterioplankton make an important contribution towards the metabolic activity in PRE.
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Graphdiyne Nanoparticles with High Free Radical Scavenging Activity for Radiation Protection.
Xie, Jiani; Wang, Ning; Dong, Xinghua; Wang, Chengyan; Du, Zhen; Mei, Linqiang; Yong, Yuan; Huang, Changshui; Li, Yuliang; Gu, Zhanjun; Zhao, Yuliang
2018-03-06
Numerous carbon networks materials comprised of benzene moieties, such as graphene and fullerene, have held great fascination for radioprotection because of their acknowledged good biocompatibility and strong free radical scavenging activity derived from their delocalized π-conjugated structure. Recently, graphdiyne, a new emerging carbon network material consisting of a unique chemical structure of benzene and acetylenic moieties, has gradually attracted attention in many research fields. Encouraged by its unique structure with strong conjugated π-system and highly reactive diacetylenic linkages, graphdiyne might have free radical activity and can thus be used as a radioprotector, which has not been investigated so far. Herein, for the first time, we synthesized bovine serum albumin (BSA)-modified graphdiyne nanoparticles (graphdiyne-BSA NPs) to evaluate their free radical scavenging ability and investigate their application for radioprotection both in cell and animal models. In vitro studies indicated that the graphdiyne-BSA NPs could effectively eliminate the free-radicals, decrease radiation-induced DNA damage in cells, and improve the viability of cells under ionizing radiation. In vivo experiments showed that the graphdiyne-BSA NPs could protect the bone marrow DNA of mice from radiation-induced damage and make the superoxide dismutase (SOD) and malondialdehyde (MDA) (two kinds of vital indicators of radiation-induced injury) recover back to normal levels. Furthermore, the good biocompatibility and negligible systemically toxicity responses of the graphdiyne-BSA NPs to mice were verified. All these results manifest the good biosafety and radioprotection activity of graphdiyne-BSA NPs to normal tissues. Therefore, our studies not only provide a new radiation protection platform based on graphdiyne for protecting normal tissues from radiation-caused injury but also provide a promising direction for the application of graphdiyne in the biomedicine field.
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Jordan, Gregor; Onami, Ichio; Heinrich, Julia; Staack, Roland F
2017-11-01
Assessment of active drug exposure of biologics may be crucial for drug development. Typically, ligand-binding assay methods are used to provide free/active drug concentrations. To what extent hybrid LC-MS/MS procedures enable correct 'active' drug quantification is currently under consideration. Experimental & results: The relevance of appropriate extraction condition was evaluated by a hybrid target capture immuno-affinity LC-MS/MS method using total and free/active quality controls (QCs). The rapid extraction (10 min) provided correct results, whereas overnight incubation resulted in significant overestimation of the free/active drug (monclonal antibody) concentration. Conventional total QCs were inappropriate to determine optimal method conditions in contrast to free/active QCs. The 'free/active analyte QC concept' enables development of appropriate extraction conditions for correct active drug quantification by hybrid LC-MS/MS.
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Human sperm degradation of zona pellucida proteins contributes to fertilization.
Saldívar-Hernández, Analilia; González-González, María E; Sánchez-Tusié, Ana; Maldonado-Rosas, Israel; López, Pablo; Treviño, Claudia L; Larrea, Fernando; Chirinos, Mayel
2015-09-02
The mammalian oocyte extracellular matrix known as the zona pellucida (ZP) acts as a barrier to accomplish sperm fusion with the female gamete. Although penetration of the ZP is a limiting event to achieve fertilization, this is one of the least comprehended stages of gamete interaction. Even though previous studies suggest that proteases of sperm origin contribute to facilitate the passage of sperm through the ZP, in human this process is not yet fully understood. The aim of this study was to determine the ability of human sperm to degrade recombinant human ZP (rhZPs) proteins and to characterize the proteases involved in this process. Purified rhZP2, rhZP3 and rhZP4 proteins were incubated with capacitated sperm and the proteolytic activity was determined by Western blot analysis. To further characterize the proteases involved, parallel incubations were performed in the presence of the protease inhibitors o-phenanthroline, benzamidine and MG-132 meant to block the activity of metalloproteases, serine proteases and the proteasome, respectively. Additionally, protease inhibitors effect on sperm-ZP binding was evaluated by hemizona assay. The results showed that rhZPs were hydrolyzed in the presence of capacitated sperm. O-phenanthroline inhibited the degradation of rhZP3, MG-132 inhibited the degradation of rhZP4 and benzamidine inhibited the degradation of the three proteins under investigation. Moreover, hemizona assays demonstrated that sperm proteasome inhibition impairs sperm interaction with human native ZP. This study suggests that sperm proteasomes could participate in the degradation of ZP, particularly of the ZP4 protein. Besides, metalloproteases may be involved in specific degradation of ZP3 while serine proteases may contribute to unspecific degradation of the ZP. These findings suggest that localized degradation of ZP proteins by sperm is probably involved in ZP penetration and may be of help in understanding the mechanisms of fertilization in humans.
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Energetic Assessment of the Nonexercise Activities under Free-Living Conditions.
Sun, Shijie; Tang, Qiang; Quan, Haiying; Lu, Qi; Sun, Ming; Zhang, Kuan
2016-01-01
Nonexercise activities (NAs) are common types of physical activity in daily life and critical component in energy expenditure. However, energetic assessment of NA, particularly in free-living subjects, is a technical challenge. In this study, mechanical modeling and portable device were used to evaluate five common types of NA in daily life: sit to stand, lie to sit, bowing while standing, squat, and right leg over left. A human indirect calorimeter was used to measure the activity energy expenditure of NA. Mechanical work and mechanical efficiency of NA were calculated for mechanical modeling. Thirty-two male subjects were recruited for the study (20 subjects for the development of models and 12 subjects for evaluation of models). The average (mean ± SD) mechanical work of 5 NAs was 2.31 ± 0.50, 2.88 ± 0.57, 1.75 ± 0.55, 3.96 ± 1.25, and 1.25 ± 0.51 J/kg·m, respectively. The mean mechanical efficiencies of those activities were 22.0 ± 3.3%, 26.5 ± 5.1%, 19.8 ± 3.7%, 24.0 ± 5.5%, and 26.3 ± 5.5%. The activity energy expenditure estimated by the models was not significantly different from the measurements by the calorimeter (p > 0.05) with accuracies of 102.2 ± 20.7%, 103.7 ± 25.8%, 105.6 ± 14.6%, 101.1 ± 28.0%, and 95.8 ± 20.7%, respectively, for those activities. These findings suggest that the mechanical models combined with a portable device can provide an alternative method for the energetic analysis of nonexercise activities under free-living condition.
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Shih, Ching-Hsiang
2013-05-01
The latest researches use software technology (OLDP, object location detection programs) to turn a commercial high-technology product, i.e. a battery-free wireless mouse, into a high performance/precise object location detector to detect whether or not an object has been placed in the designated location. The preferred environmental stimulation is also incorporated to assist those patients in need of occupational activities in performing simple occupational activities to acquire their preferred environmental stimulation. The result of the experiment shows that both participants have been able to control their preferred environmental stimulation by actively performing occupational activities. This study is going to extend the aforementioned researches by using battery-free wireless mice to assist patients in performing more complicated occupational activities. The ABAB design has been adopted for experiments, and the result shows that during intervention phrases, the occupational activities of both participants are significantly improved. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Baghaiee, Behrouz; Aliparasti, Mohammad Reza; Almasi, Shohreh; Siahkuhian, Marefat; Baradaran, Behzad
2016-06-01
Energy production is a necessary process to continue physical activities, and exercise is associated with more oxygen consumption and increase of oxidative stress. what seems important is the numerical relationship between antioxidant and free radicals. Although the activity of some enzymes increases with physical activities, but it is possible that gene expression of this enzyme is not changed during exercise. The aim of the present study is to investigate the antioxidant enzymes gene expression and changes in malondialdehyde (MDA) and total antioxidant capacity (TAC) levels in men and women affected by a session of incremental exercise and to carefully and numerically assess the relationship between MDA changes and gene expression and activity of antioxidant enzymes. 12 active men and 12 active women (21 - 24 years old) participated voluntarily in this study. Peripheral blood samples were taken from the subjects in three phases, before and after graduated exercise test (GXT) and 3 hours later (recovery). The gene expression of manganese superoxide dismutase (MnSOD) enzyme increased significantly in women in the recovery phase (P < 0.05). Catalase gene expression significantly increased in men in both phases (immediately & recovery) (P < 0.05). But the changes in active women were only significant immediately after the exercise. TAC levels increased significantly in men in the recovery phase and in active women immediately after the exercise (P < 0.05). MDA activity also increased significantly in men in both phases (P < 0.05). However, in women the increase was significant only in the recovery phase (P < 0.05). There was a reverse relationship between changes in MnSOD and copper- and zinc-containing superoxide dismutase (Cu/ZnSOD) levels and MDA in men (P < 0.05). In active women there was also a significant relationship between changes in MDA and gene expression of Cu/ZnSOD and TAC (P < 0.05). The increase in free radicals during incremental exercises challenges
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Patrat, Catherine; Auer, Jana; Fauque, Patricia; Leandri, Roger L; Jouannet, Pierre; Serres, Catherine
2006-01-01
Background The functions of three zona glycoproteins, ZP1, ZP2 and ZP3 during the sperm-zona pellucida (ZP) interaction are now well established in mice. The expression of an additional zona glycoprotein, ZPB/4, in humans, led us to reconsider the classical mouse model of gamete interaction. We investigated the various functions of human ZP (hZP) during the interaction of spermatozoa with fertilised and unfertilised oocytes. Results The hZP of fertilised oocytes retained their ability to bind sperm (albeit less strongly than that from unfertilised oocytes), to induce an intraspermatic calcium influx through voltage-dependent channels similar to that observed with hZP from unfertilised oocytes and to promote the acrosome reaction at a rate similar to that induced by the ZP of unfertilised oocytes (61.6 ± 6.2% vs60.7 ± 9.1% respectively). Conversely, the rate of hZP penetrated by sperm was much lower for fertilised than for unfertilised oocytes (19% vs 57% respectively, p < 0.01). We investigated the status of ZP2 in the oocytes used in the functional tests, and demonstrated that sperm binding and acrosome reaction induction, but not ZP penetration, occurred whether or not ZP2 was cleaved. Conclusion The change in ZP function induced by fertilisation could be different in human and mouse species. Our results suggest a zona blocking to polyspermy based at the sperm penetration level in humans. PMID:17147816
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Shi, Wei; Xu, Bo; Wu, Li-Min; Jin, Ren-Tao; Luan, Hong-Bing; Luo, Li-Hua; Zhu, Qing; Johansson, Lars; Liu, Yu-Sheng; Tong, Xian-Hong
2014-01-01
The morphological assessment of oocytes is important for embryologists to identify and select MII oocytes in IVF/ICSI cycles. Dysmorphism of oocytes decreases viability and the developmental potential of oocytes as well as the clinical pregnancy rate. Several reports have suggested that oocytes with a dark zona pellucida (DZP) correlate with the outcome of IVF treatment. However, the effect of DZP on oocyte quality, fertilization, implantation, and pregnancy outcome were not investigated in detail. In this study, a retrospective analysis was performed in 268 infertile patients with fallopian tube obstruction and/or male factor infertility. In 204 of these patients, all oocytes were surrounded by a normal zona pellucida (NZP, control group), whereas 46 patients were found to have part of their retrieved oocytes enclosed by NZP and the other by DZP (Group A). In addition, all oocytes enclosed by DZP were retrieved from 18 patients (Group B). No differences were detected between the control and group A. Compared to the control group, the rates of fertilization, good quality embryos, implantation and clinical pregnancy were significantly decreased in group B. Furthermore, mitochondria in oocytes with a DZP in both of the two study groups (A and B) were severely damaged with several ultrastructural alterations, which were associated with an increased density of the zona pellucida and vacuolization. Briefly, oocytes with a DZP affected the clinical outcome in IVF/ICSI cycles and appeared to contain more ultrastructural alterations. Thus, DZP could be used as a potential selective marker for embryologists during daily laboratory work.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Jackowski, S.; Dumont, J.N.
1979-01-01
The zona pellucida and cell surface of in vivo fertilized mouse ova exhibit time dependent changes which can be detected with the scanning electron microscope. The periods of ovulation, fertilization and first cleavage in superovulated C3D2/F/sub 1/ hybrids were determined and times corresponding to G/sub 1/, S, G/sub 2/, and M were calculated. The zona of a mature unfertilized ovum has a rough texture with deep furrows; at fertilization and thereafter the zona develops a smoother, ropy and seemingly porous surface. The cell surface of the unfertilized ovum is characterized by uniform microvilli, small blebs and rounded, mound-like elevations. Aftermore » fertilization and development to G/sub 1/, the ovum loses its blebs but retains the mound-like elevations and microvilli which are now less uniform. As the ovum progresses toward S, it loses the mound-like elevations but retains microvilli in the same density as found in G/sub 1/. The ovum in G/sub 2/ exhibits smaller but more numerous microvilli which vary considerably in length. Some appear to bifurcate. The fertilized ovum developing through M and G/sub 1/ of the 2 cell stage exhibits a less dense population of relatively uniform microvilli, periodic blebs and, again, rounded elevations. The data are reminiscent of surface changes associated with the cell cycle in tissue culture cells and indicate a cyclic progression of the in vivo fertilized mouse ovum through the first cleavage division to the 2 cell stage.« less
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Inertial measurements of free-living activities: assessing mobility to predict falls.
Wang, Kejia; Lovell, Nigel H; Del Rosario, Michael B; Liu, Ying; Wang, Jingjing; Narayanan, Michael R; Brodie, Matthew A D; Delbaere, Kim; Menant, Jasmine; Lord, Stephen R; Redmond, Stephen J
2014-01-01
An exploratory analysis was conducted into how simple features, from acceleration at the lower back and ankle during simulated free-living walking, stair ascent and descent, correlate with age, the overall fall risk from a clinically validated Physiological Profile Assessment (PPA), and its sub-components. Inertial data were captured from 92 older adults aged 78-95 (42 female, mean age 84.1, standard deviation 3.9 years). The dominant frequency, peak width from Welch's power spectral density estimate, and signal variance along each axis, from each sensor location and for each activity were calculated. Several correlations were found between these features and the physiological risk factors. The strongest correlations were from the dominant frequency at the ankle along the mediolateral direction during stair ascent (Spearman's correlation coefficient p = - 0.45) with anterioposterior sway, and signal variance of the anterioposterior acceleration at the lower back during stair descent (p = - 0.45) with age. These findings should aid future attempts to classify activities and predict falls in older adults, based on true free-living data from a range of activities.
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Reduction of Free Edge Peeling Stress of Laminated Composites Using Active Piezoelectric Layers
Huang, Bin; Kim, Heung Soo
2014-01-01
An analytical approach is proposed in the reduction of free edge peeling stresses of laminated composites using active piezoelectric layers. The approach is the extended Kantorovich method which is an iterative method. Multiterms of trial function are employed and governing equations are derived by taking the principle of complementary virtual work. The solutions are obtained by solving a generalized eigenvalue problem. By this approach, the stresses automatically satisfy not only the traction-free boundary conditions, but also the free edge boundary conditions. Through the iteration processes, the free edge stresses converge very quickly. It is found that the peeling stresses generated by mechanical loadings are significantly reduced by applying a proper electric field to the piezoelectric actuators. PMID:25025088
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Roach, Lindsay; Keats, Melanie
2018-01-01
Fundamental movement skill interventions are important for promoting physical activity, but the optimal intervention model for preschool children remains unclear. We compared two 8-week interventions, a structured skill-station and a planned active play approach, to a free-play control condition on pre- and postintervention fundamental movement skills. We also collected data regarding program attendance and perceived enjoyment. We found a significant interaction effect between intervention type and time. A Tukey honest significant difference analysis supported a positive intervention effect showing a significant difference between both interventions and the free-play control condition. There was a significant between-group difference in group attendance such that mean attendance was higher for both the free-play and planned active play groups relative to the structured skill-based approach. There were no differences in attendance between free-play and planned active play groups, and there were no differences in enjoyment ratings between the two intervention groups. In sum, while both interventions led to improved fundamental movement skills, the active play approach offered several logistical advantages. Although these findings should be replicated, they can guide feasible and sustainable fundamental movement skill programs within day care settings.
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Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-15
... Activities: Declaration for Free Entry of Unaccompanied Articles AGENCY: U.S. Customs and Border Protection...: Declaration for Free Entry of Unaccompanied Articles (Form 3299). This is a proposed extension of an... Unaccompanied Articles. OMB Number: 1651-0014. Form Number: Form 3299. Abstract: 19 U.S.C. 1498 provides that...
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Application of activated carbons from coal and coconut shell for removing free residual chlorine.
Ogata, Fumihiko; Tominaga, Hisato; Ueda, Ayaka; Tanaka, Yuko; Iwata, Yuka; Kawasaki, Naohito
2013-01-01
This study investigated the removal of free residual chlorine by activated carbon (AC). ACs were prepared from coal (AC1) and coconut shell (AC2). The specific surface area of AC1 was larger than that of AC2. The removal of free residual chlorine increased with elapsed time and amount of adsorbent. The removal mechanism of free residual chlorine was the dechlorination reaction between hypochlorous acid or hypochlorite ion and AC. Moreover, AC1 was useful in the removal of free residual chlorine in tap water. The optimum condition for the removal of free residual chlorine using a column is space velocity 306 1/h; liner velocity 6.1 m/h.
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Measuring water potential (activity) from free water to oven dryness.
Wiebe, H H
1981-12-01
Water activities (potentials) in plant materials were measured over the range from free water to oven dryness with a Spanner thermocouple psychrometer. In a two-step procedure, water was first condensed on the thermocouple junction for several minutes. The sample was then inserted under the wet thermocouple and the maximum psychrometric cooling was measured in about 10 seconds. Calibration was with saturated salt slurries of known water activities. Psychrometric cooling was a nearly linear function of the water activity and of the negative log of the water potential. The psychrometric cooling to water activity relationship agreed with wetbulb temperature depression to relative humidity relationships given in tables. Water activities of wheat grains and leaves decreased sharply in a curvilinear fashion as their water contents decreased. Some problems of the procedure are discussed.
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Gomathi, Duraisamy; Ravikumar, Ganesan; Kalaiselvi, Manokaran; Vidya, Balasubramaniam; Uma, Chandrasekar
2015-06-01
To identify the free radical scavenging activity of ethanolic extract of Evolvulus alsinoides. The free radical scavenging activity was evaluated by in vitro methods like reducing power assay, total antioxidant activity, 2,2-diphenyl-1-picrylhydrazyl (DPPH) reduction, superoxide radical scavenging activity, 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(+)) scavenging activity, hydroxyl radical scavenging assay, and nitric oxide radical scavenging assay, which were studied by using ascorbic acid as standard. The extract showed significant activities in all antioxidant assays compared with the reference antioxidant ascorbic acid. The total antioxidant activity as well as the reducing power was also found to increase in a dose-dependent manner. Evolvulus alsinoides may act as a chemopreventive agent, providing antioxidant properties and offering effective protection from free radicals.
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Stanjek-Cichoracka, A; Żegleń, S; Ramos, P; Pilawa, B; Wojarski, J
2018-06-01
The immunosuppressive drugs used in solid organ transplantation or autoimmunological processes were studied by electron paramagnetic resonance (EPR) spectroscopy to estimate their free radical scavenging activity. The interactions of immunosuppressants with free radicals were examined by an X-band (9.3 GHz) EPR spectroscopy and a model of DPPH free radicals. The EPR spectra of DPPH and DPPH interacting with individual drugs were compared. Kinetic studies were performed, and the effect of ultraviolet (UV) irradiation on the free radical scavenging activity of the tested drugs was determined. The free radical scavenging activity of non-irradiated drugs decreased in the order: rapamycin > mycophenolate mofetil > ciclosporin > tacrolimus. UV irradiation increased the free radical scavenging activity of all the tested immunosuppressive drugs, and the effect was highest for tacrolimus. For the non-irradiated samples, the speed of free radical interactions decreased in the order: ciclosporin > tacrolimus > mycophenolate mofetil > rapamycin. UV irradiation only slightly affected the speed of interactions of the immunosuppressive drugs with the model DPPH free radicals. Electron paramagnetic resonance spectroscopy is useful for obtaining information on interactions of immunosuppressive drugs with free radicals. We hypothesized that the long-term immunosuppressive effects of these drugs after transplantation or during autoimmune disorders may be mediated by anti-inflammatory action in addition to the known receptor/cell cycle inhibition. © 2018 John Wiley & Sons Ltd.
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Veitch, Jenny; Salmon, Jo; Ball, Kylie
2010-02-02
Children's unstructured outdoor free-play (or active free-play) has the potential to make an important contribution to children's overall physical activity levels. Limited research has, however, examined physical activity in this domain. This study examined associations between individual, social and physical environmental factors and the frequency with which children play in particular outdoor locations outside school hours. This study also investigated whether the frequency of playing in outdoor locations was associated with children's overall physical activity levels. Participants including 8-9 year old children and their parents (n = 187) were recruited from a selection of primary schools of varying socioeconomic status across metropolitan Melbourne, Australia. Parents completed a survey and children's overall physical activity levels were measured by accelerometry. Regression models examined the odds of children playing in various outdoor settings according to particular correlates. Inverse associations were found between preference for activities not involving physical activity, and the likelihood of children playing in the yard at home on the weekend (OR = 0.65; CI = 0.45,0.95). Positive correlates of children playing in their own street included: parental perceptions that it was safe for their child to play in their street (weekdays [OR = 6.46; CI = 2.84,14.71], weekend days [OR = 6.01; CI = 2.68,13.47]); children having many friends in their neighbourhood (OR = 2.63; CI = 1.21,5.76); and living in a cul-de-sac (weekdays [OR = 3.99; CI = 1.65,9.66], weekend days [OR = 3.49; CI = 1.49,8.16]). Positive correlates of more frequent play in the park/playground on weekdays included family going to the park together on a weekly basis on weekdays (OR = 6.8; CI = 3.4,13.6); and on weekend days (OR = 7.36; CI = 3.6,15.0). No differences in mean mins/day of moderate-vigorous physical activity were found between children in the highest and lowest tertiles for frequency
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Kiryu, Shigeru; Dodanuki, Keiichi; Takao, Hidemasa; Watanabe, Makoto; Inoue, Yusuke; Takazoe, Masakazu; Sahara, Rikisaburo; Unuma, Kiyohito; Ohtomo, Kuni
2009-04-01
To investigate the application of free-breathing diffusion-weighted MR imaging (DWI) to the assessment of disease activity in Crohn's disease. Thirty-one patients with Crohn's disease were investigated using free-breathing DWI without special patient preparation or IV or intraluminal contrast agent. The bowel was divided into seven segments, and disease activity was assessed visually on DWI. For quantitative analysis, the apparent diffusion coefficient (ADC) was measured in each segment. The findings of a conventional barium study or surgery were regarded as the gold standard for evaluating the diagnostic ability of DWI to assess disease activity. Upon visual assessment, the sensitivity, specificity, and accuracy for the detection of disease-active segments were 86.0, 81.4, and 82.4%, respectively. In the quantitative assessment, the ADC value in the disease-active area was lower than that in disease-inactive area in small and large bowels (1.61 +/- 0.44 x 10(-3) mm(2)/s versus 2.56 +/- 0.51 x 10(-3) mm(2)/s in small bowel and 1.52 +/- 0.43 x 10(-3) mm(2)/s versus 2.31 +/- 0.59 x 10(-3) mm(2)/s in large bowel, respectively, P<0.001). Free-breathing DWI is useful in the assessment of Crohn's disease. The accuracy of DWI is high in evaluating disease activity, especially in the small bowel, and the ADC may facilitate quantitative analysis of disease activity.
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Antioxidant and free radical scavenging activity of Spondias pinnata
Hazra, Bibhabasu; Biswas, Santanu; Mandal, Nripendranath
2008-01-01
Background Many diseases are associated with oxidative stress caused by free radicals. Current research is directed towards finding naturally-occurring antioxidants of plant origin. The aim of the present study was to evaluate the in vitro antioxidant activities of Spondias pinnata stem bark extract. Methods A 70% methanol extract of Spondias pinnata stem bark was studied in vitro for total antioxidant activity, for scavenging of hydroxyl radicals, superoxide anions, nitric oxide, hydrogen peroxide, peroxynitrite, singlet oxygen and hypochlorous acid, and for iron chelating capacity, reducing power, and phenolic and flavonoid contents. Results The extract showed total antioxidant activity with a trolox equivalent antioxidant concentration (TEAC) value of 0.78 ± 0.02. The IC50 values for scavenging of free radicals were 112.18 ± 3.27 μg/ml, 13.46 ± 0.66 μg/ml and 24.48 ± 2.31 μg/ml for hydroxyl, superoxide and nitric oxide, respectively. The IC50 for hydrogen peroxide scavenging was 44.74 ± 25.61 mg/ml. For the peroxynitrite, singlet oxygen and hypochlorous acid scavenging activities the IC50 values were 716.32 ± 32.25 μg/ml, 58.07 ± 5.36 μg/ml and 127.99 ± 6.26 μg/ml, respectively. The extract was found to be a potent iron chelator with IC50 = 66.54 ± 0.84 μg/ml. The reducing power was increased with increasing amounts of extract. The plant extract (100 mg) yielded 91.47 ± 0.004 mg/ml gallic acid-equivalent phenolic content and 350.5 ± 0.004 mg/ml quercetin-equivalent flavonoid content. Conclusion The present study provides evidence that a 70% methanol extract of Spondias pinnata stem bark is a potential source of natural antioxidants. PMID:19068130
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ERIC Educational Resources Information Center
Hanley, Gregory P.; Tiger, Jeffrey H.; Ingvarsson, Einar T.; Cammilleri, Anthony P.
2009-01-01
The present study evaluated the effects of classwide satiation and embedded reinforcement procedures on preschoolers' activity preferences during scheduled free-play periods. The goal of the study was to increase time allocation to originally nonpreferred, but important, activities (instructional zone, library, and science) while continuing to…
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Dickerson, B C; Miller, S L; Greve, D N; Dale, A M; Albert, M S; Schacter, D L; Sperling, R A
2007-01-01
The ability to spontaneously recall recently learned information is a fundamental mnemonic activity of daily life, but has received little study using functional neuroimaging. We developed a functional MRI (fMRI) paradigm to study regional brain activity during encoding that predicts free recall. In this event-related fMRI study, ten lists of fourteen pictures of common objects were shown to healthy young individuals and regional brain activity during encoding was analyzed based on subsequent free recall performance. Free recall of items was predicted by activity during encoding in hippocampal, fusiform, and inferior prefrontal cortical regions. Within-subject variance in free recall performance for the ten lists was predicted by a linear combination of condition-specific inferior prefrontal, hippocampal, and fusiform activity. Recall performance was better for lists in which prefrontal activity was greater for all items of the list and hippocampal and fusiform activity were greater specifically for items that were recalled from the list. Thus, the activity of medial temporal, fusiform, and prefrontal brain regions during the learning of new information is important for the subsequent free recall of this information. These fronto-temporal brain regions act together as a large-scale memory-related network, the components of which make distinct yet interacting contributions during encoding that predict subsequent successful free recall performance.
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Carvalho, Fabíola G; Negrini, Thais De Cássia; Sacramento, Luis Victor S; Hebling, Josimeri; Spolidorio, Denise M P; Duque, Cristiane
2011-01-01
The objective of this study was to evaluate the antimicrobial activity of six toothpastes for infants: 3 fluoride-free experimental toothpastes--cashew-based, mango-based and without plant extract and fluoride compared with 2 commercially fluoride-free toothpastes and 1 fluoridated toothpastes. Six toothpastes for infants were evaluated in this study: (1) experimental cashew-based toothpaste; (2) experimental mango-based toothpaste; (3) experimental toothpaste without plant extract and fluoride (negative control); (4) First Teeth brand toothpaste; (5) Weleda brand toothpaste; and (6) Tandy brand toothpaste (positive control). The antimicrobial activity was recorded against Streptococcus mutans, Streptococcus sobrinus, Lactobacillus acidophilus, and Candida albicans using the agar plate diffusion test. First Teeth, Weleda, mango-based toothpaste, and toothpaste without plant extract presented no antimicrobial effect against any of the tested micro-organisms. Cashew toothpaste had antimicrobial activity against S mutans, S sobrinus, and L acidophilus, but it showed no antimicrobial activity against C albicans. There was no statistical difference between the inhibition halo of cashew and Tandy toothpastes against S mutans and L acidophilus. Cashew fluoride-free toothpaste had inhibitory activity against Streptococcus mutans and Lactobacillus acidophilus, and these results were similar to those obtained for fluoridated toothpaste.
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NASA Astrophysics Data System (ADS)
Maggi, F.; Riley, W. J.
2016-12-01
We propose a mathematical framework to introduce the concept of differential free energy of activation in enzymatically catalyzed reactions, and apply it to N uptake by microalgae and bacteria. This framework extends the thermodynamic capabilities of the classical transition-state theory in and harmonizes the consolidated definitions of kinetic parameters with their thermodynamic and physical meaning. Here, the activation energy is assumed to be a necessary energetic level for equilibrium complexation between reactants and activated complex; however, an additional energy contribution is required for the equilibrium activated complex to release reaction products. We call this "differential free energy of activation"; it can be described by a Boltzmann distribution, and corresponds to a free energy level different from that of complexation. Whether this level is above or below the free energy of activation depends on the reaction, and defines energy domains that correspond to "superactivated", "activated", and "subactivated" complexes. The activated complex reaching one of those states will eventually release the products from an energy level different than that of activation. The concept of differential free energy of activation was tested on 57 independent experiments of NH4+ and NO3- uptake by various microalgae and bacteria at temperatures ranging between 1 and 45oC. Results showed that the complexation equilibrium always favored the activated complex, but the differential energy of activation led to an apparent energy barrier consistent with observations. Temperature affected all energy levels within this framework but did not alter substantially these thermodynamic features. Overall the approach: (1) provides a thermodynamic and mathematical link between Michaelis-Menten and rate constants; (2) shows that both kinetic parameters can be described or approximated by Arrhenius' like equations; (3) describes the likelihood of formation of sub-, super-, and
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Smart SPHERES: A Telerobotic Free-Flyer for Intravehicular Activities in Space
NASA Technical Reports Server (NTRS)
Fong, Terrence; Micire, Mark J.; Morse, Ted; Park, Eric; Provencher, Chris; To, Vinh; Wheeler, D. W.; Mittman, David; Torres, R. Jay; Smith, Ernest
2013-01-01
Smart SPHERES is a prototype free-flying space robot based on the SPHERES platform. Smart SPHERES can be remotely operated by astronauts inside a spacecraft, or by mission controllers on the ground. We developed Smart SPHERES to perform a variety of intravehicular activities (IVA), such as operations inside the International Space Station (ISS). These IVA tasks include environmental monitoring surveys (radiation, sound levels, etc.), inventory, and mobile camera work. In this paper, we first discuss the motivation for free-flying space robots. We then describe the development of the Smart SPHERES prototype, including avionics, software, and data communications. Finally, we present results of initial flight tests on-board the ISS.
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Smart SPHERES: A Telerobotic Free-Flyer for Intravehicular Activities in Space
NASA Technical Reports Server (NTRS)
Fong, Terrence; Micire, Mark J.; Morse, Ted; Park, Eric; Provencher, Chris
2013-01-01
Smart SPHERES is a prototype free-flying space robot based on the SPHERES platform. Smart SPHERES can be remotely operated by astronauts inside a spacecraft, or by mission controllers on the ground. We developed Smart SPHERES to perform a variety of intravehicular activities (IVA), such as operations inside the International Space Station (ISS). These IVA tasks include environmental monitoring surveys (radiation, sound levels, etc.), inventory, and mobile camera work. In this paper, we first discuss the motivation for free- flying space robots. We then describe the development of the Smart SPHERES prototype, including avionics, software, and data communications. Finally, we present results of initial flight tests on-board the ISS.
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Lee, Homan; Tamminen, Katherine A; Clark, Alexander M; Slater, Linda; Spence, John C; Holt, Nicholas L
2015-01-24
To produce a meta-study by completing a systematic review of qualitative research examining determinants of independent active free play in children. Following systematic electronic and manual searches and application of inclusion/exclusion criteria, 46 studies were retained and subjected to meta-method, meta-theory, and meta-data analyses, followed by a final meta-synthesis. Identified determinants of independent active free play were child characteristics (age, competence, and gender), parental restrictions (safety concerns and surveillance), neighborhood and physical environment (fewer children to play with, differences in preferences for play spaces between parents and children, accessibility and proximity, and maintenance), societal changes (reduced sense of community, good parenting ideal, changing roles of parents, privatization of playtime and play spaces), and policy issues (need to give children voice). An ecological model depicting these factors, and the relationships therein, was created. This comprehensive meta-study helps establish a knowledge base for children's independent active free play research by synthesizing a previously fragmented set of studies. Parents' perceived safety concerns are the primary barrier to children's active free play. These safety concerns are moderated by child-level factors (age, competence, gender) and broader social issues. Interventions should focus on community-level solutions that include children's perspectives. From a methods perspective, the reviewed studies used a range of data collection techniques, but methodological details were often inadequately reported. The theoretical sophistication of research in this area could be improved. To this end, the synthesis reported in this study provides a framework for guiding future research.
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Liao, Yue; Chou, Chih-Ping; Huh, Jimi; Leventhal, Adam; Dunton, Genevieve
2017-08-01
Affective response during physical activity may influence motivation to perform future physical activity behavior. However, affective response during physical activity is often assessed under controlled laboratory conditions. The current study used ecological momentary assessment (EMA) to capture affective responses during free-living physical activity performed by adults, and determined whether these affective responses predict future moderate-to-vigorous physical activity (MVPA) levels after 6 and 12 months. At baseline, electronic EMA surveys were randomly prompted across 4 days asking about current activities and affective states (e.g., happy, stressed, energetic, tired). Affective response during physical activity was operationalized as the level of positive or negative affect reported when concurrent physical activity (e.g., exercise or sports) was also reported. Data were available for 82 adults. Future levels of moderate-to-vigorous physical activity (MVPA) were measured using accelerometers, worn for seven consecutive days at 6 and 12 months after the baseline assessment. Feeling more energetic during physical activity was associated with performing more minutes of daily MVPA after both 6 and 12 months. Feeling less negative affect during physical activity was associated with engaging in more daily MVPA minutes after 12 months only. This study demonstrated how EMA can be used to capture affective responses during free-living physical activity. Results found that feelings more energetic and less negative during physical activity were associated with more future physical activity, suggesting that positive emotional benefits may reinforce behavior.
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2010-01-01
Background Children's unstructured outdoor free-play (or active free-play) has the potential to make an important contribution to children's overall physical activity levels. Limited research has, however, examined physical activity in this domain. This study examined associations between individual, social and physical environmental factors and the frequency with which children play in particular outdoor locations outside school hours. This study also investigated whether the frequency of playing in outdoor locations was associated with children's overall physical activity levels. Methods Participants including 8-9 year old children and their parents (n = 187) were recruited from a selection of primary schools of varying socioeconomic status across metropolitan Melbourne, Australia. Parents completed a survey and children's overall physical activity levels were measured by accelerometry. Regression models examined the odds of children playing in various outdoor settings according to particular correlates. Results Inverse associations were found between preference for activities not involving physical activity, and the likelihood of children playing in the yard at home on the weekend (OR = 0.65; CI = 0.45,0.95). Positive correlates of children playing in their own street included: parental perceptions that it was safe for their child to play in their street (weekdays [OR = 6.46; CI = 2.84,14.71], weekend days [OR = 6.01; CI = 2.68,13.47]); children having many friends in their neighbourhood (OR = 2.63; CI = 1.21,5.76); and living in a cul-de-sac (weekdays [OR = 3.99; CI = 1.65,9.66], weekend days [OR = 3.49; CI = 1.49,8.16]). Positive correlates of more frequent play in the park/playground on weekdays included family going to the park together on a weekly basis on weekdays (OR = 6.8; CI = 3.4,13.6); and on weekend days (OR = 7.36; CI = 3.6,15.0). No differences in mean mins/day of moderate-vigorous physical activity were found between children in the highest and
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Mfotie Njoya, Emmanuel; Munvera, Aristide Mfifen; Mkounga, Pierre; Nkengfack, Augustin Ephrem; McGaw, Lyndy Joy
2017-04-04
Free radicals have been implicated in the pathogenesis of diverse metabolic disorders including cancer. Therefore, fighting against free radicals has become an important strategy in the prevention or treatment of such diseases, in addition to direct or indirect anticancer chemotherapy. Sarcocephalus pobeguinii has been used traditionally to treat various diseases in which excess production of free radicals is implicated, warranting investigation of its free radical scavenging, anticancer and anti-inflammatory activity. In the present study, extracts from leaves, fruits, roots and bark of Sarcocephalus pobeguinii were evaluated on four human cancer cell lines (MCF-7, HeLa, Caco-2 and A549 cells) and a non-cancerous cell line for their antiproliferative potential. The cells were incubated with the plant extracts for 48 h at 37 °C in a 5% CO 2 humidified environment and their cytotoxic effect was determined using the tetrazolium-based colorimetric (MTT) assay. The radical inhibition was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and the 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging techniques. The nitric oxide inhibitory activity was determined using LPS-activated RAW 264.7 macrophages. The correlation between radical scavenging capacity and antiproliferative activity was also analysed. The extract from leaves of Sarcocephalus pobeguinii (LSP) exhibited the highest cytotoxic effect on all four of the human cancer cell lines but with some cytotoxicity to the normal Vero cells. However, the LSP extract had the best selectivity index, ranging from 3.15 to 18.28. Also, antioxidant and anti-inflammatory assays indicated that the LSP extract had the highest radical scavenging capacity of all the extracts. A positive linear correlation was found between free radical scavenging ability and antiproliferative activity against the four cancer cell lines, with the highest correlation factor (R 2 = 0.9914) obtained between DPPH
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Dickerson, B.C.; Miller, S.L.; Greve, D.N.; Dale, A.M.; Albert, M.S.; Schacter, D.L.; Sperling, R.A.
2009-01-01
The ability to spontaneously recall recently learned information is a fundamental mnemonic activity of daily life, but has received little study using functional neuroimaging. We developed a functional MRI (fMRI) paradigm to study regional brain activity during encoding that predicts free recall. In this event-related fMRI study, ten lists of fourteen pictures of common objects were shown to healthy young individuals and regional brain activity during encoding was analyzed based on subsequent free recall performance. Free recall of items was predicted by activity during encoding in hippocampal, fusiform, and inferior prefrontal cortical regions. Within-subject variance in free recall performance for the ten lists was predicted by a linear combination of condition-specific inferior prefrontal, hippocampal, and fusiform activity. Recall performance was better for lists in which pre-frontal activity was greater for all items of the list and hippocampal and fusi-form activity were greater specifically for items that were recalled from the list. Thus, the activity of medial temporal, fusiform, and prefrontal brain regions during the learning of new information is important for the subsequent free recall of this information. These fronto-temporal brain regions act together as a large-scale memory-related network, the components of which make distinct yet interacting contributions during encoding that predict subsequent successful free recall performance. PMID:17604356
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Veitch, Jenny; Bagley, Sarah; Ball, Kylie; Salmon, Jo
2006-12-01
This study explored the perceptions of 78 parents from low, mid and high socio-economic areas in Melbourne, Australia to increase understanding of where children play and why. Using an ecological model interviews with parents revealed that safety and social factors emerged as key social themes, facilities at parks and playgrounds, and urban design factors emerged as important physical environment themes. The children's level of independence and attitudes to active free-play were considered to be important individual level influences on active free-play. The study findings have important implications for future urban planning and children's opportunities for active free-play.
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Automation and Optimization of Multipulse Laser Zona Drilling of Mouse Embryos During Embryo Biopsy.
Wong, Christopher Yee; Mills, James K
2017-03-01
Laser zona drilling (LZD) is a required step in many embryonic surgical procedures, for example, assisted hatching and preimplantation genetic diagnosis. LZD involves the ablation of the zona pellucida (ZP) using a laser while minimizing potentially harmful thermal effects on critical internal cell structures. Develop a method for the automation and optimization of multipulse LZD, applied to cleavage-stage embryos. A two-stage optimization is used. The first stage uses computer vision algorithms to identify embryonic structures and determines the optimal ablation zone farthest away from critical structures such as blastomeres. The second stage combines a genetic algorithm with a previously reported thermal analysis of LZD to optimize the combination of laser pulse locations and pulse durations. The goal is to minimize the peak temperature experienced by the blastomeres while creating the desired opening in the ZP. A proof of concept of the proposed LZD automation and optimization method is demonstrated through experiments on mouse embryos with positive results, as adequately sized openings are created. Automation of LZD is feasible and is a viable step toward the automation of embryo biopsy procedures. LZD is a common but delicate procedure performed by human operators using subjective methods to gauge proper LZD procedure. Automation of LZD removes human error to increase the success rate of LZD. Although the proposed methods are developed for cleavage-stage embryos, the same methods may be applied to most types LZD procedures, embryos at different developmental stages, or nonembryonic cells.
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Dynamic regulation of sperm interactions with the zona pellucida prior to and after fertilisation.
Gadella, B M
2012-01-01
Recent findings have refined our thinking on sperm interactions with the cumulus-oocyte complex (COC) and our understanding of how, at the molecular level, the sperm cell fertilises the oocyte. Proteomic analyses has identified a capacitation-dependent sperm surface reordering that leads to the formation of functional multiprotein complexes involved in zona-cumulus interactions in several mammalian species. During this process, multiple docking of the acrosomal membrane to the plasma membrane takes place. In contrast with the dogma that the acrosome reaction is initiated when spermatozoa bind to the zona pellucida (ZP), it has been established recently that, in mice, the fertilising spermatozoon initiates its acrosome reaction during its voyage through the cumulus before it reaches the ZP. In fact, even acrosome-reacted mouse spermatozoa collected from the perivitelline space can fertilise another ZP-intact oocyte. The oviduct appears to influence the extracellular matrix properties of the spermatozoa as well as the COC. This may influence sperm binding and penetration of the cumulus and ZP, and, in doing so, increase monospermic while decreasing polyspermic fertilisation rates. Structural analysis of the ZP has shed new light on how spermatozoa bind and penetrate this structure and how the cortical reaction blocks sperm-ZP interactions. The current understanding of sperm interactions with the cumulus and ZP layers surrounding the oocyte is reviewed with a special emphasis on the lack of comparative knowledge on this topic in humans, as well as in most farm mammals.
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Liu, Ying-Lei; Chen, Ying; Zhou, Cheng-Jie; Wu, Sha-Na; Shen, Jiang-Peng; Liang, Cheng-Guang
2014-01-01
To improve the outcome of assisted reproductive technology (ART) for patients with ovulation problems, it is necessary to retrieve and select germinal vesicle (GV) stage oocytes with high developmental potential. Oocytes with high developmental potential are characterized by their ability to undergo proper maturation, fertilization, and embryo development. In this study, we analyzed morphological traits of GV stage mouse oocytes, including cumulus cell layer thickness, zona pellucida thickness, and perivitelline space width. Then, we assessed the corresponding developmental potential of each of these oocytes and found that it varies across the range measured for each morphological trait. Furthermore, by manipulating these morphological traits in vitro, we were able to determine the influence of morphological variation on oocyte developmental potential. Manually altering the thickness of the cumulus layer showed strong effects on the fertilization and embryo development potentials of oocytes, whereas manipulation of zona pellucida thickness effected the oocyte maturation potential. Our results provide a systematic detailed method for selecting GV stage oocytes based on a morphological assessment approach that would benefit for several downstream ART applications. PMID:25144310
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Hamazaki, T.S.; Nagahama, Y.; Iuchi, I.
1989-05-01
A glycoprotein from the liver, which shares epitopes with chorion (egg envelope or zona pellucida) glycoproteins, is present only in the spawning female fish, Oryzias latipes, under natural conditions. This spawning female-specific (SF) substance is distinct from vitellogenin but closely resembles a major glycoprotein component, ZI-3, of the inner layer (zona radiata interna) of the ovarian egg envelope with respect to some biochemical and immunochemical characteristics. Here we report that the (/sup 125/I)SF substance, injected into the abdominal cavity of the spawning female fish, was rapidly transported by the blood circulation into the ovary and incorporated into the inner layermore » of egg envelope of the growing oocytes. The result strongly suggests that the SF substance from the liver is a precursor substance of the major component, ZI-3, of the inner layer of egg envelope in the fish.« less
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Free radical activity and hemostatic factors in NIDDM patients with and without microalbuminuria.
Collier, A; Rumley, A; Rumley, A G; Paterson, J R; Leach, J P; Lowe, G D; Small, M
1992-08-01
In non-insulin-dependent diabetes mellitus (NIDDM) patients, microalbuminuria predicts early mortality, predominantly from cardiovascular disease. Increased free radical activity and abnormalities in hemostasis have been implicated in the development of vascular disease. Therefore, we measured markers of free radical activity (nonperoxide-conjugated diene isomer of linoleic acid [PL-9,11-LA'] and lipid peroxides expressed as malondialdehyde [MDA]) along with the hemostatic variables: fibrinogen, von Willebrand factor (vWf), plasminogen activator inhibitor (PAI-1), tissue plasminogen activator (t-PA), and plasmin activity (B beta 15-42) in 24 NIDDM patients (12 patients with microalbuminuria and 12 without microalbuminuria) and in 12 age-matched control subjects. There were no differences in linoleic acid (PL-9,12-LA) concentrations between the three groups. PL-9,11-LA' was elevated in the microalbuminuric patients compared with control subjects (P less than 0.05), but there was no difference between the two diabetic groups. MDA was elevated in the microalbuminuric diabetic patients compared with those patients without microalbuminuria (P less than 0.05) and control subjects (P less than 0.001). MDA was also increased in the patients without microalbuminuria compared with control subjects (P less than 0.01). Except for B beta 15-42, all the hemostatic variables were increased (P less than 0.05) in the diabetic patients compared with control subjects. The microalbuminuric diabetic patients had further increases in vWf (P less than 0.03) and t-PA (P less than 0.03) compared with patients with microalbuminuria. Our study suggests that there is an increase in free radical activity and abnormalities in hemostatic variables favoring a hypercoagulable state in NIDDM, especially in those with microalbuminuria.(ABSTRACT TRUNCATED AT 250 WORDS)
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Children's active free play in local neighborhoods: a behavioral mapping study.
Veitch, J; Salmon, J; Ball, K
2008-10-01
Many Australian children are more sedentary than they should be, and almost one in five are currently overweight or obese. Some children may face difficulties finding opportunities to be active, having poor access to safe public open spaces or having low independent mobility limiting their access to places to play. This study aimed to examine children's access to places in their neighborhood for active free play and how these vary by age, sex and socioeconomic status (SES). Behavioral maps of the local neighborhood were completed by children (8-12 years) from five primary schools across different areas of Melbourne. Children living in low SES outer-urban neighborhoods had to travel greater distances to access local parks compared with those in inner-urban mid and high SES areas. One-third (32%) of children reported an independent mobility range of <100 m from home. In conclusion, for some children opportunities to engage in active free play in the local neighborhood may be limited due to lack of parks in close proximity to home and restricted independent mobility. It is important to collaborate with local governments, urban planners and community groups to improve access to neighborhood parks and to promote a sense of neighborhood safety.
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Incentivos para atraer y retener personal de salud de zonas rurales del Perú: un estudio cualitativo
Huicho, Luis; Canseco, Francisco Díez; Lema, Claudia; Miranda, J. Jaime; Lescano, Andrés G.
2014-01-01
El objetivo fue identificar incentivos de atracción y retención en zonas rurales y distantes de Ayacucho, Perú. Fueron realizadas entrevistas en profundidad con 80 médicos, enfermeras, obstetras y técnicos (20 por grupo) de las zonas más pobres y con 11 funcionarios. No existen políticas sistemáticas de atracción y retención de personal de salud en Ayacucho. Los principales incentivos, en orden de importancia, fueron mejoras salariales, oportunidades de formación y capacitación, estabilidad laboral y nombramiento, mejoras en infraestructura y equipos, e incremento del personal. Se mencionaron también mejoras en la vivienda y alimentación, mayor cercanía con la familia y reconocimiento por el sistema de salud. Existen coincidencias y singularidades entre los distintos grupos sobre los incentivos clave para estimular el trabajo rural, que deben considerarse al diseñar políticas públicas. Las iniciativas del Estado deben comprender procesos rigurosos de monitoreo y evaluación, para asegurar que las mismas tengan el impacto deseado. PMID:22488318
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Favoured Free-Time: Comparing Children's Activity Preferences in the UK and the USA
ERIC Educational Resources Information Center
Griffiths, Merris
2011-01-01
This study presents a comparative study of the free-time activity preferences of 9- to 11-year-old children in the UK and USA, as drawn by them in art workshops. Six themes emerged relating to sport, outdoor play, family/peers, media, special occasions and other (indefinable) activities. The children's talk about their drawings revealed additional…
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Measuring Water Potential (Activity) from Free Water to Oven Dryness 1
Wiebe, Herman H.
1981-01-01
Water activities (potentials) in plant materials were measured over the range from free water to oven dryness with a Spanner thermocouple psychrometer. In a two-step procedure, water was first condensed on the thermocouple junction for several minutes. The sample was then inserted under the wet thermocouple and the maximum psychrometric cooling was measured in about 10 seconds. Calibration was with saturated salt slurries of known water activities. Psychrometric cooling was a nearly linear function of the water activity and of the negative log of the water potential. The psychrometric cooling to water activity relationship agreed with wetbulb temperature depression to relative humidity relationships given in tables. Water activities of wheat grains and leaves decreased sharply in a curvilinear fashion as their water contents decreased. Some problems of the procedure are discussed. Images PMID:16662081
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Alzahrani, Matar A.; Dean, Catherine M.; Ada, Louise; Dorsch, Simone; Canning, Colleen G.
2012-01-01
Purpose. To determine which characteristics are most associated with free-living physical activity in community-dwelling ambulatory people after stroke. Method. Factors (age, gender, side of stroke, time since stroke, BMI, and spouse), sensory-motor impairments (weakness, contracture, spasticity, coordination, proprioception, and balance), and non-sensory-motor impairments (cognition, language, perception, mood, and confidence) were collected on 42 people with chronic stroke. Free-living physical activity was measured using an activity monitor and reported as time on feet and activity counts. Results. Univariate analysis showed that balance and mood were correlated with time on feet (r = 0.42, 0.43, P < 0.01) and also with activity counts (r = 0.52, 0.54, P < 0.01). Stepwise multiple regression showed that mood and balance accounted for 25% of the variance in time on feet and 40% of the variance in activity counts. Conclusions. Mood and balance are associated with free-living physical activity in ambulatory people after stroke residing in the community. PMID:22013550
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YouGuo, Chen; ZongJi, Shen; XiaoPing, Chen
2009-12-01
In this study, antioxidant and immunity-modulatory activities of Purslane polysaccharide were estimated. The results revealed that in a dose-dependent manner, Purslane polysaccharides could significantly scavenge superoxide anion, 1,1-diphenyl-2-picrylhydrazyl (DPPH(-)), nitric oxide and hydroxyl radicals. Furthermore, the Purslane polysaccharides could still effectively inhibit the red blood cell (RBC) haemolysis, and increase spleen, thymocyte T and B lymphocyte proliferation, it could be concluded that Purslane polysaccharides could be of considerable preventive and therapeutic significance to some free radical associated health problems such as ovarian cancer, by scavenging accumulating free radicals and enhancing immunity functions.
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Cuberek, Roman; Ansari, Walid El; Frömel, Karel; Skalik, Krzysztof; Sigmund, Erik
2010-01-01
This study assessed and compared the daily step counts recorded by two different motion sensors in order to estimate the free-living physical activity of 135 adolescent girls. Each girl concurrently wore a Yamax pedometer and an ActiGraph accelerometer (criterion measure) every day for seven consecutive days. The convergent validity of the pedometer can be considered intermediate when used to measure the step counts in free-living physical activity; but should be considered with caution when used to classify participants’ step counts into corresponding physical activity categories because of a likelihood of ‘erroneous’ classification in comparison with the accelerometer. PMID:20617046
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Manoharan, Indumathi; Boopathy, Rathnam
2006-08-15
Butyrylcholinesterase in human plasma and acetylcholinesterase in human red blood cells have aryl acylamidase activity toward o-nitroacetanilide, hydrolyzing the amide bond to produce o-nitroaniline and acetate. People with a genetic variant of butyrylcholinesterase that had no detectable activity with butyrylthiocholine, nevertheless had aryl acylamidase activity in their plasma. To determine the source of this aryl acylamidase activity we tested fatty acid free human albumin for activity. We found that albumin had aryl acylacylamidase activity and that this activity was inhibited by diisopropylfluorophosphate. Since the esterase activity of albumin is also inhibited by diisopropylfluorophosphate, and since it is known that diisopropylfluorophosphate covalently binds to Tyr 411 of human albumin, we conclude that the active site for aryl acylamidase activity of albumin is Tyr 411. Albumin accounts for about 10% of the aryl acylamidase activity in human plasma.
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Rahman, Md Mahbubur; Islam, Md Badrul; Biswas, Mohitosh; Khurshid Alam, A H M
2015-10-30
In humans, many diseases are associated with the accumulation of free radicals. Antioxidants can scavenge free radicals and minimize their impact. Therefore, the search for naturally occurring antioxidants of plant origin is imperative. Here, we aimed to investigate the antioxidant and free radical scavenging properties of methanolic extracts from Tabebuia pallida (T. pallida) stem bark (TPSB), root bark (TPRB), leaves (TPL), and flowers (TPF). The antioxidant and free radical scavenging activity were determined by several standard methods using spectrophotomer. Total phenolic and flavonoid contents were estimated using Folin-Ciocalteu reagent and aluminum chloride colorimetric assay methods, respectively. Among the extracts, TPL showed the highest total antioxidant capacity followed by TPRB, TPF, and TPSB. Based on DPPH and hydroxyl radical scavenging activity, TPL showed strong scavenging activity (91.05 ± 1.10 and 62.00 ± 0.57) with IC50 of 9.20 ± 0.28 and 46.00 ± 2.84 μg/mL, respectively when compared with standard BHT (IC50 of 7.00 ± 0.25 μg/mL) and CA (75.00 ± 0.14 μg/mL). These results suggest that TPL had the highest radical scavenging activity among the extractives that closely resembled the standard's. In lipid peroxidation inhibition assay, TPL exhibited the most potent inhibitory activity (83.18 ± 2.12 %) with IC50 of 12.00 ± 2.12 μg/mL, which closely resembled standard CA (IC50 of 10.50 ± 0.28 μg/mL). Also, the reducing capacity on ferrous ion was in the following order: TPL > TPRB > TF > TPSB. The phenolic and flavonoid contents of TPL were higher than other extractives. A positive correlation (p value <0.001) was observed between phenolic content and free radical (DPPH(·) and (·)OH) scavenging efficiencies and lipid peroxidation inhibition activity. Methanolic extract of T. pallida leaf is a potential source of natural antioxidants and serves as an effective free radical scavenger and/or inhibitor. Hence, T. pallida might be a good
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Muscle activation in the loaded free barbell squat: a brief review.
Clark, Dave R; Lambert, Mike I; Hunter, Angus M
2012-04-01
The purpose of this article was to review a series of studies (n = 18) where muscle activation in the free barbell back squat was measured and discussed. The loaded barbell squat is widely used and central to many strength training programs. It is a functional and safe exercise that is obviously transferable to many movements in sports and life. Hence, a large and growing body of research has been published on various aspects of the squat. Training studies have measured the impact of barbell squat loading schemes on selected training adaptations including maximal strength and power changes in the squat. Squat exercise training adaptations and their impact on a variety of performance parameters, in particular countermovement jump, acceleration, and running speed, have also been reported. Furthermore, studies have reported on the muscle activation of the lower limb resulting from variations of squat depth, foot placement, training status, and training intensity. There have also been studies on the impact of squatting with or without a weight belt on trunk muscle activation (TMA). More recently, studies have reported on the effect of instability on TMA and squat performance. Research has also shown that muscle activation of the prime movers in the squat exercise increases with an increase in the external load. Also common variations such as stance width, hip rotation, and front squat do not significantly affect muscle activation. However, despite many studies, this information has not been consolidated, resulting in a lack of consensus about how the information can be applied. Therefore, the purpose of this review was to examine studies that reported muscle activation measured by electromyography in the free barbell back squat with the goal of clarifying the understanding of how the exercise can be applied.
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A Comparison of Free Time Activity Choices of Third Culture Kids in Albania and Children in the UK
ERIC Educational Resources Information Center
Purdon, Anne
2018-01-01
This study aims to consider children's perspectives about free time activity choices. Through the use of drawings, favourite free time activities of third culture kids in Albania are compared with those of children in the UK. The sample comprises four boys and three girls from four to eight years from each country. Further conversations reveal…
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Malin, Stephanie A; Mayer, Adam; Shreeve, Kelly; Olson-Hazboun, Shawn K; Adgate, John
2017-01-01
Unconventional oil and gas extraction (UOGE) has spurred an unprecedented boom in on-shore production in the U.S. Despite a surge in related research, a void exists regarding inquiries into policy outcomes and perceptions. To address this, support for federal regulatory exemptions for UOGE is examined using survey data collected in 2015 from two northern Colorado communities. Current regulatory exemptions for UOGE can be understood as components of broader societal processes of neoliberalization. Free market ideology increases public support for federal regulatory exemptions for UOGE. Perceived negative impacts do not necessarily drive people to support increased federal regulation. Utilizing neo-Polanyian theory, interaction between free market ideology and perceived negative impacts is explored. Free market ideology appears to moderate people's views of regulation: increasing the effect of perceived negative impacts while simultaneously increasing support for de regulation. To conclude, the ways in which free market ideology might normalize the impacts of UOGE activity are discussed.
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Zhou, Guifen; Lv, Guiyuan
2012-06-01
To study the scavenging DPPH free radicals activity of flavone C-glycosides from different parts of Dendrobium officinale. The types and contents of flavonoids from different parts of D. officinale were analyzed by TLC and HPLC. The antioxidant effect was tested by scavenging DPPH free radicals activity. The stems, leaves and flowers contained the same type of flavone C-A glycosides and 8 common peaks were identified. The content of flavone C-A glycosides was significantly different. The content of flavone C-glycosides in leaves and flowers was higher than that in stems. The flavonoid in roots was less. Stems contained naringenin, which was not identified in root, leave and flower. Both stems and leaves had antioxidant capacity of eliminating DPPH free radicals, of which scavenging DPPH free radicals activity of leaves was better than stems. Considering the content of flavonoid and antioxidant activity leave and flower of D. officinale may substitute stems. The study provides a preliminary basis for the development and utilization of leave and flower of D. officinale.
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ERIC Educational Resources Information Center
Karlsson, Fredrik; Olofsson, Katarina; Blomstedt, Patric; Linder, Jan; van Doorn, Jan
2013-01-01
Purpose: The purpose of the present study was to examine the effect of deep brain stimulation (DBS) of the subthalamic nucleus (STN) and the caudal zona incerta (cZi) pitch characteristics of connected speech in patients with Parkinson's disease (PD). Method: The authors evaluated 16 patients preoperatively and 12 months after DBS surgery. Eight…
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Overview of the 1986 free-piston Stirling SP-100 activities at the NASA Lewis Research Center
NASA Technical Reports Server (NTRS)
Slaby, J. G.
1986-01-01
An overview of the NASA Lewis Research Center SP-100 free-piston Stirling engine activities is presented. These activities include a free-piston Stirling space-power technology feasibility demonstration project as part of the SP-100 program being conducted in support of the Department of Defennse (DOD), Department of Energy (DOE), and NASA. The space-power Stirling advanced technology effort, under SP-100, addresses the status of the 25 kWe Space Power Demonstrator Engine (SPDE) including test results. Future space-power projections are presented along with a description of a study that will investigate the feasibility of scaling a single-cylinder free-piston Stirling space-power module to the 150 kW power range. Design parameters and conceptual design features will be presented for a 25 kWe, single-cylinder free-piston Stirling space-power converter. A description of a hydrodynamic gas bearing concept is presented whereby the displacer of a 1 kWe free-piston Stirling engine is modified to demonstrate the bearing concept. And finally the goals of a conceptual design for a 25 kWe Solar Advanced Stirling Conversion System capable of delivering electric power to an electric utility grid are discussed.
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Overview of the 1986 free-piston Stirling SP-100 activities at the NASA Lewis Research Center
NASA Technical Reports Server (NTRS)
Slaby, J. G.
1986-01-01
An overview of the NASA Lewis Research Center SP-100 free-piston Stirling engine activities is presented. These activities include a free-piston Stirling space-power technology feasibility demonstration project as part of the SP-100 program being conducted in support of the Department of Defense (DOD), Department of Energy (DOE), and NASA. The space-power Stirling advanced technology effort, under SP-100, addresses the status of the 25 kWe Space Power Demonstrator Engine (SPDE) including test results. Future space-power projections are presented along with a description of a study that will investigate the feasibility of scaling a single-cylinder free-piston Stirling space-power module to the 150 kW power range. Design parameters and conceptual design features will be presented for a 25 kWe, single-cylinder free-piston Stirling space-power converter. A description of a hydrodynamic gas bearing concept is presented whereby the displacer of a 1 kWe free-piston Stirling engine is modified to demonstrate the bearing concept. And finally the goals of a conceptual design for a 25 kWe Solar Advanced Stirling Conversion System capable of delivering electric power to an electric utility grid are discussed.
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A Robust and Device-Free System for the Recognition and Classification of Elderly Activities.
Li, Fangmin; Al-Qaness, Mohammed Abdulaziz Aide; Zhang, Yong; Zhao, Bihai; Luan, Xidao
2016-12-01
Human activity recognition, tracking and classification is an essential trend in assisted living systems that can help support elderly people with their daily activities. Traditional activity recognition approaches depend on vision-based or sensor-based techniques. Nowadays, a novel promising technique has obtained more attention, namely device-free human activity recognition that neither requires the target object to wear or carry a device nor install cameras in a perceived area. The device-free technique for activity recognition uses only the signals of common wireless local area network (WLAN) devices available everywhere. In this paper, we present a novel elderly activities recognition system by leveraging the fluctuation of the wireless signals caused by human motion. We present an efficient method to select the correct data from the Channel State Information (CSI) streams that were neglected in previous approaches. We apply a Principle Component Analysis method that exposes the useful information from raw CSI. Thereafter, Forest Decision (FD) is adopted to classify the proposed activities and has gained a high accuracy rate. Extensive experiments have been conducted in an indoor environment to test the feasibility of the proposed system with a total of five volunteer users. The evaluation shows that the proposed system is applicable and robust to electromagnetic noise.
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Merkiel, Sylwia; Chalcarz, Wojciech; Deptuła, Monika
2011-01-01
The aim of this study was to compare physical activity of preschool girls and boys from the Mazowsze region and their favourite ways of spending free time. The studied population included 131 children aged 3 to 7 years. Parents filled in questionnaires about their children's physical activity and favourite ways of spending free time, as well as about general information on the children and their families. Gender had statistically significant influence on the children's birth weight, attending karate outside the preschool and on riding a bicycle, playing with a ball and playing with a dog as favourite ways of spending free time during sunny weather as well as playing on a computer and playing with dolls as favourite ways of spending free time during rainy weather. Gender had little influence on the studied preschoolers' physical activity. However favourite ways of spending free time turned out to be significantly different according to gender. Physical activity level in both girls and boys was low, similarly to their peers from the previous studies.
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Afrimzon, Elena; Deutsch, Assaf; Shafran, Yana; Zurgil, Naomi; Sandbank, Judith; Pappo, Itzhak; Deutsch, Mordechai
2008-01-01
One of the major clinical problems in breast cancer detection is the relatively high incidence of occult lymph node metastases undetectable by standard procedures. Since the ascertainment of breast cancer stage determines the following treatment, such a "hypo-diagnosis" leads to inadequate therapy, and hence is detrimental for the outcome and survival of the patients. The purpose of our study was to investigate functional metabolic characteristics of living cells derived from metastatic and tumor-free lymph nodes of breast cancer (BC) patients. Our methodology is based on the ability of living cells to hydrolyze fluorescein diacetate (FDA) by intracellular esterases and on the association of FDA hydrolysis rates with a specific cell status, both in physiological and pathological conditions. The present study demonstrates a significant difference in the ability to utilize FDA by lymph node cells derived from metastatic and tumor-free lymph nodes in general average, as well as in the metastatic and tumor-free lymph nodes of individual patients. Cells from metastatic lymph nodes had a higher capacity for FDA hydrolysis, and increased this activity after additional activation by autologous tumor tissue (tt). The association between increased FDA hydrolysis rate and activated T lymphocytes and antigen-presenting cells (APC) was shown. The results of the present study may contribute to predicting the risk of involvement of seemingly "tumor-free" axillary lymph nodes in occult metastatic processes, and to reducing false-negative results of axillary examination.
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Cell-free NADPH oxidase activation assays: "in vitro veritas".
Pick, Edgar
2014-01-01
The superoxide (O2 (∙-))-generating NADPH oxidase complex of phagocytes comprises a membrane-imbedded heterodimeric flavocytochrome, known as cytochrome b 558 (consisting of Nox2 and p22 (phox) ) and four cytosolic regulatory proteins, p47 (phox) , p67 (phox) , p40 (phox) , and the small GTPase Rac. Under physiological conditions, in the resting phagocyte, O2 (∙-) generation is initiated by engagement of membrane receptors by a variety of stimuli, followed by specific signal transduction sequences leading to the translocation of the cytosolic components to the membrane and their association with the cytochrome. A consequent conformational change in Nox2 initiates the electron "flow" along a redox gradient, from NADPH to oxygen, leading to the one-electron reduction of molecular oxygen to O2 (∙-). Methodological difficulties in the dissection of this complex mechanism led to the design "cell-free" systems (also known as "broken cells" or in vitro systems). In these, membrane receptor stimulation and all or part of the signal transduction sequence are missing, the accent being placed on the actual process of "NADPH oxidase assembly," thus on the formation of the complex between cytochrome b 558 and the cytosolic components and the resulting O2 (∙-) generation. Cell-free assays consist of a mixture of the individual components of the NADPH oxidase complex, derived from resting phagocytes or in the form of purified recombinant proteins, exposed in vitro to an activating agent (distinct from and unrelated to whole cell stimulants), in the presence of NADPH and oxygen. Activation is commonly quantified by measuring the primary product of the reaction, O2 (∙-), trapped immediately after its generation by an appropriate acceptor in a kinetic assay, permitting the calculation of the linear rate of O2 (∙-) production, but numerous variations exist, based on the assessment of reaction products or the consumption of substrates. Cell-free assays played a paramount
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ERIC Educational Resources Information Center
Shih, Ching-Hsiang; Chang, Man-Ling
2012-01-01
This study extended Battery-free wireless mouse functionality to assess whether two people with developmental disabilities would be able to actively perform designated simple occupational activities according to simple instructions by controlling their favorite environmental stimulation using Battery-free wireless mice with a newly developed…
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Lu, Tzy-Ming; Ko, Horng-Huey; Ng, Lean-Teik; Hsieh, Yen-Pin
2015-06-01
In this study, we examined the potential of synthetic isoflavones for application in cosmeceuticals. Twenty-five isoflavones were synthesized and their capacities of free-radical-scavenging and mushroom tyrosinase inhibition, as well as their impact on cell viability of B16F10 murine melanoma cells and HaCaT human keratinocytes were evaluated. Isoflavones that showed significant mushroom tyrosinase inhibitory activities were further studied on reduction of cellular melanin formation and antityrosinase activities in B16F10 melanocytes in vitro. Among the isoflavones tested, 6-hydroxydaidzein (2) was the strongest scavenger of both ABTS(.+) and DPPH(.) radicals with SC50 values of 11.3 ± 0.3 and 9.4 ± 0.1 μM, respectively. Texasin (20) exhibited the most potent inhibition of mushroom tyrosinase (IC50 14.9 ± 4.5 μM), whereas retusin (17) showed the most efficient inhibition both of cellular melanin formation and antityrosinase activity in B16F10 melanocytes, respectively. In summary, both retusin (17) and texasin (20) exhibited potent free-radical-scavenging capacities as well as efficient inhibition of cellular melanogenesis, suggesting that they are valuable hit compounds with potential for advanced cosmeceutical development. Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.
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Undeveloped green space and free-time physical activity in 11 to 13-year-old children.
Janssen, Ian; Rosu, Andrei
2015-02-21
Research on the association between the physical environment and physical activity in children has focused on built and developed features or total green space. The impact of natural, undeveloped green spaces is unknown. The objective of this study was to determine whether the presence of undeveloped green spaces in the home neighborhood are associated with physical activity in 11 to 13-year-olds. This was a cross-sectional study of grade 6 to 8 urban residing Canadian students who participated in the 2009/10 Health Behaviour in School-Aged Children survey. Children self-reported the frequency they participated in physical activity in their free-time outside of school hours. Geographic Information Systems (GIS) were used to assess the proportion of land area within 1 km of participants' homes that was devoted to publicly accessible meadows (i.e., field vegetated primarily by grass and other non-woody plants) and treed areas (i.e., field vegetated primarily by trees and shrubs). Ordinal logistic regression models were used to examine the relationships between the undeveloped green space areas and free-time physical activity. Several intrapersonal, family, and neighborhood environment factors were controlled for in these regression models. The proportion of neighborhood land covered by meadows was not associated with the physical activity outcome (p > 0.6). However, the proportion of neighborhood land covered by treed areas was independently associated with the physical activity outcome (p = 0.02). For each additional 5% increase in the proportion of neighborhood land covered by treed areas there was a corresponding 5% increase (95% confidence interval: 1-10% increase) in the relative odds of increasing free-time physical activity outside of school hours. The physical activity levels of 11 to 13-year-old children was associated with the amount of space in their home neighborhood devoted to treed areas.
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Double C-H activation of ethane by metal-free SO2*+ radical cations.
de Petris, Giulia; Cartoni, Antonella; Troiani, Anna; Barone, Vincenzo; Cimino, Paola; Angelini, Giancarlo; Ursini, Ornella
2010-06-01
The room-temperature C-H activation of ethane by metal-free SO(2)(*+) radical cations has been investigated under different pressure regimes by mass spectrometric techniques. The major reaction channel is the conversion of ethane to ethylene accompanied by the formation of H(2)SO(2)(*+), the radical cation of sulfoxylic acid. The mechanism of the double C-H activation, in the absence of the single activation product HSO(2)(+), is elucidated by kinetic studies and quantum chemical calculations. Under near single-collision conditions the reaction occurs with rate constant k=1.0 x 10(-9) (+/-30%) cm(3) s(-1) molecule(-1), efficiency=90%, kinetic isotope effect k(H)/k(D)=1.1, and partial H/D scrambling. The theoretical analysis shows that the interaction of SO(2)(*+) with ethane through an oxygen atom directly leads to the C-H activation intermediate. The interaction through sulfur leads to an encounter complex that rapidly converts to the same intermediate. The double C-H activation occurs by a reaction path that lies below the reactants and involves intermediates separated by very low energy barriers, which include a complex of the ethyl cation suitable to undergo H/D scrambling. Key issues in the observed reactivity are electron-transfer processes, in which a crucial role is played by geometrical constraints. The work shows how mechanistic details disclosed by the reactions of metal-free electrophiles may contribute to the current understanding of the C-H activation of ethane.
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A method to estimate free-living active and sedentary behavior from an accelerometer.
Lyden, Kate; Keadle, Sarah Kozey; Staudenmayer, John; Freedson, Patty S
2014-02-01
Methods to estimate physical activity (PA) and sedentary behavior (SB) from wearable monitors need to be validated in free-living settings. The purpose of this study was to develop and validate two novel machine-learning methods (Sojourn-1 Axis [soj-1x] and Sojourn-3 Axis [soj-3x]) in a free-living setting. Participants were directly observed in their natural environment for 10 consecutive hours on three separate occasions. Physical activity and SB estimated from soj-1x, soj-3x, and a neural network previously calibrated in the laboratory (lab-nnet) were compared with direct observation. Compared with lab-nnet, soj-1x and soj-3x improved estimates of MET-hours (lab-nnet: % bias [95% confidence interval] = 33.1 [25.9 to 40.4], root-mean-square error [RMSE] = 5.4 [4.6-6.2]; soj-1x: % bias = 1.9 [-2.0 to 5.9], RMSE = 1.0 [0.6 to 1.3]; soj-3x: % bias = 3.4 [0.0 to 6.7], RMSE = 1.0 [0.6 to 1.5]) and minutes in different intensity categories {lab-nnet: % bias = -8.2 (sedentary), -8.2 (light), and 72.8 (moderate-to-vigorous PA [MVPA]); soj-1x: % bias = 8.8 (sedentary), -18.5 (light), and -1.0 (MVPA); soj-3x: % bias = 0.5 (sedentary), -0.8 (light), and -1.0 (MVPA)}. Soj-1x and soj-3x also produced accurate estimates of guideline minutes and breaks from sedentary time. Compared with the lab-nnet algorithm, soj-1x and soj-3x improved the accuracy and precision in estimating free-living MET-hours, sedentary time, and time spent in light-intensity activity and MVPA. In addition, soj-3x is superior to soj-1x in differentiating SB from light-intensity activity.
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Jeran, S; Steinbrecher, A; Pischon, T
2016-08-01
Activity-related energy expenditure (AEE) might be an important factor in the etiology of chronic diseases. However, measurement of free-living AEE is usually not feasible in large-scale epidemiological studies but instead has traditionally been estimated based on self-reported physical activity. Recently, accelerometry has been proposed for objective assessment of physical activity, but it is unclear to what extent this methods explains the variance in AEE. We conducted a systematic review searching MEDLINE database (until 2014) on studies that estimated AEE based on accelerometry-assessed physical activity in adults under free-living conditions (using doubly labeled water method). Extracted study characteristics were sample size, accelerometer (type (uniaxial, triaxial), metrics (for example, activity counts, steps, acceleration), recording period, body position, wear time), explained variance of AEE (R(2)) and number of additional predictors. The relation of univariate and multivariate R(2) with study characteristics was analyzed using nonparametric tests. Nineteen articles were identified. Examination of various accelerometers or subpopulations in one article was treated separately, resulting in 28 studies. Sample sizes ranged from 10 to 149. In most studies the accelerometer was triaxial, worn at the trunk, during waking hours and reported activity counts as output metric. Recording periods ranged from 5 to 15 days. The variance of AEE explained by accelerometer-assessed physical activity ranged from 4 to 80% (median crude R(2)=26%). Sample size was inversely related to the explained variance. Inclusion of 1 to 3 other predictors in addition to accelerometer output significantly increased the explained variance to a range of 12.5-86% (median total R(2)=41%). The increase did not depend on the number of added predictors. We conclude that there is large heterogeneity across studies in the explained variance of AEE when estimated based on accelerometry. Thus
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Overview of the 1986 free-piston Stirling activities at NASA Lewis Research Center
NASA Technical Reports Server (NTRS)
Alger, Donald L.
1986-01-01
An overview of the NASA Lewis Research Center's free-piston Stirling engine research is presented, including efforts to improve and advance its design for use in specific space power applications. These efforts are a part of the SP-100 program being conducted to support the Department of Defense (DOD), Department of Energy (DOE) and NASA. Such efforts include: (1) the testing and improvement of 25 kWe Stirling Space Power Demonstrator Engine (SPDE); (2) the preliminary design of 25 kWe single-cylinder Experimental stirling Space Engine (ESSE); and, (3) a study to determine the feasibility of scaling a single-cylinder free-piston Stirling engine/linear alternator to 150 kWe. Other NASA Lewis free-piston Stirling engine activities will be described, directed toward the advancement of general free-piston Stirling engine technology and its application in specific terrestrial applications. One such effort, supported by DOE/Oak Ridge National Laboratory (DRNL), is the development of a free-piston Stirling engine which produces hydraulic power. Finally, a terrestrial solar application involving a conceptual design of a 25 kWe Solar Advanced Stirling Conversion System (ASCS) capable of delivering power to an electric utility grid will be discussed. The latter work is supported by DOE/Sandia National Laboratory (SNLA).
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Flavonoids: hemisynthesis, reactivity, characterization and free radical scavenging activity.
Es-Safi, Nour-Eddine; Ghidouche, Souhila; Ducrot, Paul Henri
2007-09-26
Phenolic compounds form one of the main classes of secondary metabolites. They display a large range of structures and they are responsible for the major organoleptic characteristics of plant-derived-foods and beverages, particularly color and taste properties and they also contribute to the nutritional qualities of fruits and vegetables. Phenolic compounds are also highly unstable compounds which undergo numerous enzymatic and chemical reactions during postharvest food storage and processing thus adding to the complexity of plant polyphenol composition. Among these compounds flavonoids constitute one of the most ubiquitous groups of all plant phenolics. Owing to their importance in food organoleptic properties and in human health, a better understanding of their structures, their reactivity and chemical properties in addition to the mechanisms generating them appears essential to predict and control food quality. The purpose of this work is an overview of our findings concerning the hemisynthesis, the reactivity and the enzymatic oxidation of some flavonoids and shed light on the mechanisms involved in some of these processes and the structures of the resulting products. The free radical scavenging activity of some of the synthesized compounds is also presented and a structure-activity relationship is discussed. The first part of this review concerns the synthesis and structural characterization of modified monomeric flavanols. The use of these compounds as precursor for the preparation of natural and modified dimeric procyanidin derivatives was then explored through different coupling reactions. The full characterization of the synthesized compounds was achieved by concerted use of NMR and ESI-MS techniques. The free radical scavenging activity of some of the synthesized compounds was investigated. The second part of this review concerns the enzymatic oxidation of several flavonols by Trametes versicolor laccase. Most of the major oxidation products have been
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Free Black Activism in the Antebellum North
ERIC Educational Resources Information Center
Rael, Patrick
2006-01-01
In 1860, 226,000 (47 percent) of the US' 478,000 free blacks lived in free states, and thus totaled over five percent of the black population in America. Though oppressed by popular prejudice and a range of legal and institutional constraints--in 1847, blacks at a convention labeled themselves "slaves of the community"--African Americans outside…
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2018-01-01
To explore the potential of berries as natural sources of bioactive compounds, the quantities of free, esterified, and insoluble-bound phenolic acids in a number of berries were determined. In addition, the antioxidant activities of the berries were determined using 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, ferric reducing antioxidant power, and Trolox equivalent antioxidant capacity assays, in addition to determination of their metal ion chelating activities. Furthermore, several phenolic compounds were detected using high-performance liquid chromatography. Of the 6 tested berries, black chokeberry and blackberry exhibited the strongest antioxidant activities, and the various berry samples were found to contain catechin, caffeic acid, p-coumaric acid, epicatechin, vanillic acid, quercitrin, resveratrol, morin, naringenin, and apigenin. Moreover, the antioxidant activities and total phenolic contents of the fractions containing insoluble-bound phenolic acids were higher than those containing the free and esterified phenolic acids. The results imply that the insoluble-bound fractions of these berries are important natural sources of antioxidants for the preparation of functional food ingredients and preventing diseases associated with oxidative stress. PMID:29662846
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Antigenotoxic and free radical scavenging activities of extracts from Moricandia arvensis.
Skandrani, I; Sghaier, M Ben; Neffati, A; Boubaker, J; Bouhlel, I; Kilani, S; Mahmoud, A; Ghedira, K; Chekir-Ghedira, L
2007-01-01
This study evaluates genotoxic and antigenotoxic effects of extracts from leaves of Moricandia arvensis, which are used in traditional cooking and medicines. Extracts showed no genotoxicity when tested with the SOS Chromotest using E. coli PQ37 and PQ35 strains, except for the total oligomers flavonoids enriched extract. Petroleum ether and methanol extracts are the most active in reducing nitrofurantoin genotoxicity, whereas methanol and total oligomers flavonoids enriched extracts showed the most important inhibitory effect of H2O2 genotoxicity. In addition, these two extracts showed important free radical scavenging activity toward the DPPH. radical, whereas the chloroform extract exhibited the highest value of TEAC against ABTS+. radical.
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Concurrent Validity of Wearable Activity Trackers Under Free-Living Conditions.
Brooke, Skyler M; An, Hyun-Sung; Kang, Seoung-Ki; Noble, John M; Berg, Kris E; Lee, Jung-Min
2017-04-01
Brooke, SM, An, H-S, Kang, S-K, Noble, JM, Berg, KE, and Lee, J-M. Concurrent validity of wearable activity trackers under free-living conditions. J Strength Cond Res 31(4): 1097-1106, 2017-The purpose of this study is to evaluate the concurrent validity of wearable activity trackers in energy expenditure (EE) and sleep period time (SPT) under free-living conditions. Ninety-five (28.5 ± 9.8 years) healthy men (n = 34) and women (n = 61) participated in this study. The total EE and SPT were measured using 8 monitors: Nike+ FuelBand SE (NFB), Garmin VivoFit (VF), Misfit Shine (MF), Fitbit Flex (FF), Jawbone UP (JU), Polar Loop (PL), Fitbit Charge HR (FC), and SenseWear Armband Mini (SWA) (criterion measures: SWA for EE and a sleep log for SPT). The mean absolute percent error (MAPE) for EE was 13.0, 15.2, 15.5, 16.1, 16.2, 22.8, and 24.5% for PL, MF, FF, NFB, FC, JU, and VF, respectively. Mean absolute percent errors were calculated for SPT to be 4.0, 8.8, 10.2, 11.5, 12.9, 13.6, 17.5, and 21.61% for VF, FF, JU, FC, MF, SWA laying down, PL, and SWA, respectively. Concurrent validity was examined using equivalence testing on EE (equivalence zone: 2,889.7-3,531.9 kcal); 2 trackers fell short of falling in the zone: PL (2,714.4-3,164.8 kcal) and FC (2,473.8-3,066.5 kcal). For SPT (equivalence zone: 420.6-514.0 minutes), several monitors fell in the zone: PL (448.3-485.6 minutes), MS (442.8-492.2 minutes), and FF (427.7-486.7 minutes). This study suggests that the PL and FC provide a reasonable estimate of EE under free-living conditions. The PL, FC, and MF were the most valid monitors used for measuring SPT.
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Rosenblat, M; Elias, A; Volkova, N; Aviram, M
2013-04-01
In the current study, we analysed free radicals scavenging activity of monocytes-macrophages in the absence or presence of antioxidants such as polyphenols or paraoxonase 1 (PON1). THP-1 human monocytic cell line, murine J774A.1 macrophages, as well as human primary monocytes have the capability to scavenge free radicals, as measured by the 1-diphenyl-2-picryl-hydrazyl (DPPH) assay. This effect (which could be attributed to the cell's membrane) was cell number and incubation time dependent. Upon incubation of J774A.1 macrophages with acetylated LDL (Ac-LDL), with VLDL, or with the radical generator, AAPH, the cells' lipid peroxides content, and paraoxonase 2 (PON2) activity were significantly increased. While non-treated cells decreased DPPH absorbance by 65%, the Ac-LDL-, VLDL- or AAPH-treated cells, decreased it by only 33%, 30%, or 45%, respectively. We next analysed the effect of J774A.1 macrophage enrichment with antioxidants, such as polyphenols or PON1 on the cells' free radicals scavenging activity. Non-treated cells decreased DPPH absorbance by 50%, whereas vitamin E-, punicalagin- or PJ-treated cells significantly further decreased it, by 75%. Similarly, in PON1-treated cells DPPH absorbance was further decreased by 63%, in association with 23% increment in PON1 catalytic activity. In cells under oxidative stress [treated with AAPH-, or with oxidized LDL], PON1 activity was decreased by 31% or 40%, as compared to the activity observed in PON1 incubated with non-treated cells. We conclude that monocytes-macrophages possess free radicals scavenging activity, which is decreased under atherogenic conditions, and increased upon cell enrichment with potent antioxidants such as nutritional polyphenols, or PON1.
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Microanatomical diversification of the zona pellucida in aplochelioid killifishes.
Thompson, A W; Furness, A I; Stone, C; Rade, C M; Ortí, G
2017-07-01
This study investigates zona pellucida (ZP) ultrastructure in fertilized eggs of annual killifishes (suborder Aplocheiloidei), a group of highly specialized fishes that are able to survive desiccation for several weeks to months before they hatch. Little is known about ZP or chorionic ultrastructure sustaining these life-history modes, so scanning electron microscopy (SEM) was used to describe this trait in a large number of aplocheiloids with a focus on the family Rivulidae and the genus Hypsolebias. New images of ZP ultrastructure for 52 aplocheiloid species are provided, more than doubling the number characterized thus far. The evolution of chorionic structure within this group is studied using these new data. Characters were coded into a morphological matrix and optimized onto a consensus phylogeny to assess phylogenetic signal and reconstruct ancestral character states. Although ZP characters seem highly homoplastic and exhibit a large amount of structural convergence among lineages, aplocheiloid killifishes have evolved a number of unique structures associated with the chorion. Some annual species seem to have lost long filaments because eggs are deposited in the soil instead of being adhered to aquatic plants. © 2017 The Fisheries Society of the British Isles.
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Runge, D M; Runge, D; Dorko, K; Pisarov, L A; Leckel, K; Kostrubsky, V E; Thomas, D; Strom, S C; Michalopoulos, G K
1999-02-01
Serum-free primary cultures of hepatocytes are a useful tool to study factors triggering hepatocyte proliferation and regeneration. We have developed a chemically defined serum-free system that allows human hepatocyte proliferation in the presence of epidermal growth factor and hepatocyte growth factor. DNA synthesis and accumulation were determined by [3H]thymidine incorporation and fluorometry, respectively. Western blot analyses and co-immunoprecipitations were used to investigate the association of proteins involved in epidermal growth factor and hepatocyte growth factor activation and signaling: epidermal growth factor receptor, hepatocyte growth factor receptor (MET), urokinase-type plasminogen activator and its receptor, and a member of the signal transducer and activator of transcription family, STAT-3. Primary human hepatocytes proliferated under serum-free conditions in a chemically defined medium for up to 12 days. Epidermal growth factor-receptor and MET were present and functional, decreasing over time. MET, urokinase-type plasminogen activator and urokinase-type plasminogen activator receptor co-precipitated to varying degrees during the culture period. STAT-3 co-precipitated with epidermal growth factor-receptor and MET to varying degrees. Proliferation of human hepatocytes can improve by modification of a chemically defined medium originally used for rat hepatocyte cultures. In these long-term cultures of human hepatocytes, hepatocyte growth factor and epidermal growth factor can stimulate growth and differentiation by interacting with their receptors and initiating downstream signaling. This involves complex formation of the receptors with other plasma membrane components for MET (urokinase-type plasminogen activator in context of its receptor) and activation of STAT-3 for both receptors.
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Malin, Stephanie A.; Mayer, Adam; Shreeve, Kelly; Olson-Hazboun, Shawn K.; Adgate, John
2017-01-01
Unconventional oil and gas extraction (UOGE) has spurred an unprecedented boom in on-shore production in the U.S. Despite a surge in related research, a void exists regarding inquiries into policy outcomes and perceptions. To address this, support for federal regulatory exemptions for UOGE is examined using survey data collected in 2015 from two northern Colorado communities. Current regulatory exemptions for UOGE can be understood as components of broader societal processes of neoliberalization. Free market ideology increases public support for federal regulatory exemptions for UOGE. Perceived negative impacts do not necessarily drive people to support increased federal regulation. Utilizing neo-Polanyian theory, interaction between free market ideology and perceived negative impacts is explored. Free market ideology appears to moderate people’s views of regulation: increasing the effect of perceived negative impacts while simultaneously increasing support for deregulation. To conclude, the ways in which free market ideology might normalize the impacts of UOGE activity are discussed. PMID:29225425
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Bell, D; Jackson, M; Nicoll, J J; Millar, A; Dawes, J; Muir, A L
1990-01-01
Activated neutrophils releasing proteolytic enzymes and oxygen free radicals have been implicated in extending myocardial injury after myocardial infarction. Neutrophil elastase was used as a marker of neutrophil activation and the non-peroxide diene conjugate of linoleic acid was used as an indicator of free radical activity in 32 patients after acute myocardial infarction; 17 were treated by intravenous thrombolysis. Patients with acute myocardial infarction had higher plasma concentrations of neutrophil elastase and the non-peroxide diene conjugated isomer of linoleic acid than normal volunteers or patients with stable ischaemic heart disease. Patients treated by thrombolysis had an early peak of neutrophil elastase at eight hours while those who had not been treated by thrombolysis showed a later peak 40 hours after infarction. The plasma concentration of non-peroxide conjugated diene of linoleic acid was highest 16 hours after the infarction irrespective of treatment by thrombolysis. Quantitative imaging with single photon emission tomography showed decreased uptake of indium-111 labelled neutrophils in the infarcted myocardium (as judged from technetium-99m pyrophosphate) in those who had received thrombolysis, suggesting a decreased inflammatory response. The results indicate increased neutrophil activation and free radical production after myocardial infarction; they also suggest that thrombolysis does not amplify the inflammatory response and may indeed suppress it. Images PMID:2317413
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NASA Astrophysics Data System (ADS)
Shaik, Firdoz; Zhang, Weiqing; Niu, Wenxin; Lu, Xianmao
2014-10-01
Ligand-free Au nanoparticles with controlled sizes are synthesized via a volume-confined method. In this synthesis, mesoporous hollow silica shells (mHSS) are used as nano-containers for the impregnation of HAuCl4 solution before they are separated from the bulk solution. With a simple heating process, the Au precursor confined within the cavity of the isolated hollow shells is converted into ligand-free Au nanoparticles. The size of the Au nanoparticles can be tuned precisely by loading HAuCl4 solution of different concentrations, or by using mHSS with different cavity volumes. The ligand-free Au nanoparticles demonstrate superior catalytic activity than sodium citrate-capped Au nanoparticles.
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Continuous theory of active matter systems with metric-free interactions.
Peshkov, Anton; Ngo, Sandrine; Bertin, Eric; Chaté, Hugues; Ginelli, Francesco
2012-08-31
We derive a hydrodynamic description of metric-free active matter: starting from self-propelled particles aligning with neighbors defined by "topological" rules, not metric zones-a situation advocated recently to be relevant for bird flocks, fish schools, and crowds-we use a kinetic approach to obtain well-controlled nonlinear field equations. We show that the density-independent collision rate per particle characteristic of topological interactions suppresses the linear instability of the homogeneous ordered phase and the nonlinear density segregation generically present near threshold in metric models, in agreement with microscopic simulations.
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Effects of acrolein on aldosterone release from zona glomerulosa cells in male rats.
Wang, Kai-Lee; Huang, Wen-Ching; Chou, Jou-Chun; Weng, Ting-Chun; Hu, Sindy; Lieu, Fu-Kong; Lai, Wei-Ho; Idova, Galina; Wang, Paulus S; Wang, Shyi-Wu
2016-07-01
A positive correlation between smoking and hypertension has been well established. Acrolein is a major toxic volatile compound found in cigarette smoke. Human exposure to low levels of acrolein is unavoidable due to its production in daily activities, such as smoke from industrial, hot oil cooking vapors, and exhaust fumes from vehicles. The toxicity and the action mechanism of acrolein to induce apoptosis have been extensively studied, but the effects of acrolein on hypertension are still unknown. The present study aimed to examine the effects of acrolein on aldosterone release both in vivo and in vitro. Male rats were divided into three groups, and intraperitoneally injected with normal saline, or acrolein (2mg/kg) for 1 (group A-1) or 3 (group A-3) days, respectively. After sacrificing, rat blood samples were obtained to measure plasma aldosterone and angiotensin II (Ang II) levels. Zona glomerulosa (ZG) cells were prepared from rat adrenal cortex, and were incubated with or without stimulants. We found that the serum aldosterone was increased by 1.2-fold (p<0.05) in A-3 group as compared to control group. Basal aldosterone release from ZG cells in A-3 group was also increased significantly. Moreover, acrolein enhanced the stimulatory effects of Ang II and 8-bromo-cyclic AMP on aldosterone secretion from ZG cells prepared in both A-1 and A-3 groups. Furthermore, the enzyme activity of P450scc, the rate-limiting step of aldosterone synthesis, was elevated after acrolein injection. Plasma level of Ang II was increased in both A-1 and A-3 groups. These results suggested that acrolein exposure increased aldosterone production, at least in part, through elevating the level of plasma Ang II and stimulating steroidogenesis pathways. Copyright © 2016 Elsevier Inc. All rights reserved.
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Nagaoka, Shin-Ichi; Bandoh, Yuki; Nagashima, Umpei; Ohara, Keishi
2017-10-26
Singlet-oxygen ( 1 O 2 ) quenching, free-radical scavenging, and excited-state intramolecular proton-transfer (ESIPT) activities of hydroxyflavones, anthocyanidins, and 1-hydroxyanthraquinones were studied by means of laser, stopped-flow, and steady-state spectroscopies. In hydroxyflavones and anthocyanidins, the 1 O 2 quenching activity positively correlates to the free-radical scavenging activity. The reason for this correlation can be understood by considering that an early step of each reaction involves electron transfer from the unfused phenyl ring (B-ring), which is singly bonded to the bicyclic chromen or chromenylium moiety (A- and C-rings). Substitution of an electron-donating OH group at B-ring enhances the electron transfer leading to activation of the 1 O 2 quenching and free-radical scavenging. In 3-hydroxyflavones, the OH substitution at B-ring reduces the activity of ESIPT within C-ring, which can be explained in terms of the nodal-plane model. As a result, the 1 O 2 quenching and free-radical scavenging activities negatively correlate to the ESIPT activity. A catechol structure at B-ring is another factor that enhances the free-radical scavenging in hydroxyflavones. In contrast to these hydroxyflavones, 1-hydroxyanthraquinones having an electron-donating OH substituent adjacent to the O-H---O═C moiety susceptible to ESIPT do not show a simple correlation between their 1 O 2 quenching and ESIPT activities, because the OH substitution modulates these reactions.
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Antimicrobial and free radical scavenging activities of five Palestinian medicinal plants.
Qabaha, Khaled Ibraheem
2013-01-01
Extracts from five indigenous Palestinian medicinal plants including Rosmarinus officinalis, Pisidium guajava, Punica granatum peel, grape seeds and Teucrium polium were investigated for antimicrobial and free radical scavenging activities against eight microorganisms, using well diffusion method. The microorganisms included six bacterial isolates (i.e. Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginos, Klebsiella pneumonia, Bacillus subtilis and Micrococcus luteus) and two fungal isolates (i.e. Candida albicans and Aspergillus niger). A standard antioxidant assay was performed on the plant extracts to assess their capability in scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH). Of the five tested plant extract, only Rosmarinus offcinalis extract contained significant antimicrobial activity against all eight microbial isolates including Pseudomonas aeruginosa. Extracts from other four plants exhibited a variable antimicrobial activity against all microorganisms, except Pseudomonas aeruginosa. Significant antioxidant activity was detected in all plant extracts. However, extracts from Pisidium guajava leaves contained significantly higher antioxidant activity compared to the other extracts tested. The antimicrobial and scavenging activities detected in this in vitro study in extracts from the five Palestinian medicinal plants suggest that further study is needed to identify active compounds to target diseases caused by a wide-spectrum pathogens.
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Cho, Jeong-Yong; Lee, Sang-Hyun; Kim, Eun Hee; Yun, Hae Rim; Jeong, Hang Yeon; Lee, Yu Geon; Kim, Wol-Soo; Moon, Jae-Hak
2015-01-01
Changes in chemical constituent contents and DPPH radical-scavenging activity in fruits of pear (Pyrus pyrifolia) cultivars during the development were investigated. The fruits of seven cultivars (cv. Niitaka, Chuhwangbae, Wonhwang, Hwangkeumbae, Hwasan, Manpungbae, and Imamuraaki) were collected at 15-day intervals after day 20 of florescence. Vitamins (ascorbic acid and α-tocopherol), arbutin, chlorogenic acid, malaxinic acid, total caffeic acid, total flavonoids, and total phenolics were the highest in immature pear fruit on day 20 after florescence among samples at different growth stages. All of these compounds decreased gradually in the fruit during the development. Immature pear fruit on day 35 or 50 after florescence exhibited higher free radical-scavenging activity than that at other times, although activities were slightly different among cultivars. The chemical constituent contents and free radical-scavenging activity were largely different among immature fruits of the pear cultivars, but small differences were observed when they matured.
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Free radicals in tetanic activity of isolated skeletal muscle.
Koren, A; Sauber, C; Sentjurc, M; Schara, M
1983-01-01
1. The concentration of the free radicals in muscle tissue mitochondria changes with the phase of muscle contraction. 2. Potassium cyanide (KCN) influences the shape of the isotonic tetani mechanograms; the contraction is still strong and qualitatively comparable in amplitude to untreated controls. 3. On the other hand, the correlation between the free radical concentration and muscle contraction is lost. 4. The free radical concentration in isolated mitochondria is influenced by KCN and potassium ferricyanide. 5. The free radical concentration changes due to the electron flow in the respiratory chain. 6. Inhibition of the respiratory phosphorylation by KCN could affect the free radical level.
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Deng, M Q; Fan, B Q
1994-09-01
Oocytes collected 18-19 h after HCG injection were stimulated with 7-8% ethanol or electrical pulses (1.7 KV/cm field strength, 80-100 microseconds duration, 3-4 times, 5-6 min interval). The parthenogenetic embryos derived from the above-mentioned methods developed to blastocyst stage just like those developed from fertilized eggs. Mouse oocytes were rather sensitive to ethanol stimulation. More than 95% of the treated oocytes were activated after stimulation of 7-8% ethanol for 5 min. Multiple electrical stimulations induced higher activation percentages of oocytes than only single electrical stimulation (71.5% vs. 63.6%). Intact oocytes were loaded with fluorescent Ca2+ indicator fura-2 and intracellular free calcium changes during artificial activation were measured by fluorescence detector. The results showed that ethanol could induce repetitive transient Ca2+ concentration increase in activated oocytes. Single electrical stimulation only induced single free calcium concentration elevation in oocyte while multiple electrical pulses could induce repetitive Ca2+ increase (each electrical pulse elicited the corresponding Ca2+ concentration peak). The pronuclei were not observed in the oocytes which had not exhibited calcium concentration rise during activation. Apart from electrical stimulation parameter, sufficient amount of Ca2+ in electric medium was crucial to mouse oocyte activation when stimulated with electrical pulses. The oocytes were hardly activated by electrical stimulations in a medium without Ca2+ even with longer pulse duration and the intracellular free calcium concentration in the oocytes showed no elevation. This indicates that the inflow of extracellular Ca2+ from tiny pores across the oocyte membrane caused by electrical stimulation is the main source of intracellular free calcium increase.(ABSTRACT TRUNCATED AT 250 WORDS)
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Hexavalent Chromate Reductase Activity in Cell Free Extracts of Penicillium sp.
Arévalo-Rangel, Damaris L.; Cárdenas-González, Juan F.; Martínez-Juárez, Víctor M.; Acosta-Rodríguez, Ismael
2013-01-01
A chromium-resistant fungus isolated from contaminated air with industrial vapors can be used for reducing toxic Cr(VI) to Cr(III). This study analyzes in vitro reduction of hexavalent chromium using cell free extract(s) of the fungus that was characterized based on optimal temperature, pH, use of electron donors, metal ions and initial Cr(VI) concentration in the reaction mixture. This showed the highest activity at 37°C and pH 7.0; there is an increase in Cr(VI) reductase activity with addition of NADH as an electron donor, and it was highly inhibited by Hg2+, Ca2+ and Mg2+, and azide, EDTA, and KCN. PMID:24027493
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Cell-Free and In Vivo Characterization of Lux, Las, and Rpa Quorum Activation Systems in E. coli.
Halleran, Andrew D; Murray, Richard M
2018-02-16
Synthetic biologists have turned toward quorum systems as a path for building sophisticated microbial consortia that exhibit group decision making. Currently, however, even the most complex consortium circuits rely on only one or two quorum sensing systems, greatly restricting the available design space. High-throughput characterization of available quorum sensing systems is useful for finding compatible sets of systems that are suitable for a defined circuit architecture. Recently, cell-free systems have gained popularity as a test-bed for rapid prototyping of genetic circuitry. We take advantage of the transcription-translation cell-free system to characterize three commonly used Lux-type quorum activators, Lux, Las, and Rpa. We then compare the cell-free characterization to results obtained in vivo. We find significant genetic crosstalk in both the Las and Rpa systems and substantial signal crosstalk in Lux activation. We show that cell-free characterization predicts crosstalk observed in vivo.
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Fragkou, S; Balasouli, C; Tsuzukibashi, O; Argyropoulou, A; Menexes, G; Kotsanos, N; Kalfas, S
2016-10-01
This was to examine the occurrence of S. mutans, S. sobrinus and C. albicans in dental plaque and saliva from caries-free and caries-active Greek children. Saliva and dental plaque samples from 46 caries-free and 51 caries-active 3-to-13-year-old children were examined using selective media for the three microbes. Identification of isolated mutans streptococci (S. mutans and S. sobrinus) was performed with biochemical test and specific DNA probes. The salivary levels of mutans streptococci were additionally determined by a chair-side test (Dentocult ® SM strips). The isolation frequencies of S. mutans, S. sobrinus and C. albicans were 66, 11 and 18 %, respectively. Caries-active children harboured more frequently and at significantly higher numbers the specific microbes than caries-free children. A similar pattern was observed with the Dentocult ® SM strip scores. No correlation was found between the presence of these microbes and the age or gender of the children. Caries experience was statistically significantly related to the presence of all three microbes under study, both in dental plaque and saliva.
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Liu, J; Mori, A
1992-12-01
Gastrodia elata Bl. (GE) and Uncaria rhynchophylla (Miq.) Jacks (UR) are two traditional Chinese medicinal herbal drugs, used for the treatment of convulsions and epilepsy. Their antioxidant effects in vivo and their free radical scavenging effects in vitro were investigated. Epileptogenic foci in the lateral brain of the rat were induced by the injection of ferric chloride into the lateral cortex. Both extracts significantly inhibited the increase in levels of lipid peroxide in the ipsilateral cortex, at all times observed. In addition, the two extracts also induced an early increase of activity of superoxide dismutase in the mitochondrial fraction of the ipsilateral cortex. In in vitro experiments, the two extracts exhibited significant dose-dependent scavenging effects on free radicals, using electron spin resonance spectroscopy. These results suggest that the proposed antiepileptic effects of GE and UR may be attributable to the antioxidant activity of the active components in these two medicinal herbs.
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NASA Astrophysics Data System (ADS)
Bi, Chuan-Xing; Hu, Ding-Yu; Zhang, Yong-Bin; Jing, Wen-Qian
2015-06-01
In previous studies, an equivalent source method (ESM)-based technique for recovering the free sound field in a noisy environment has been successfully applied to exterior problems. In order to evaluate its performance when applied to a more general noisy environment, that technique is used to identify active sources inside cavities where the sound field is composed of the field radiated by active sources and that reflected by walls. A patch approach with two semi-closed surfaces covering the target active sources is presented to perform the measurements, and the field that would be radiated by these target active sources into free space is extracted from the mixed field by using the proposed technique, which will be further used as the input of nearfield acoustic holography for source identification. Simulation and experimental results validate the effectiveness of the proposed technique for source identification in cavities, and show the feasibility of performing the measurements with a double layer planar array.
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2014-01-01
Background The phenolic contents and antioxidant activities of fruits could be underestimated if the bound phenolic compounds are not considered. In the present study, the extraction efficiencies of various solvents were investigated in terms of the total content of the free and bound phenolic compounds, as well as the phenolic profiles and antioxidant activities of the extracts. Methods Five different solvent mixtures were used to extract the free phenolic compounds from litchi pulp. Alkaline and acidic hydrolysis methods were compared for the hydrolysis of bound phenolic compounds from litchi pulp residue. The phenolic compositions of the free and bound fractions from the litchi pulp were identified using HPLC-DAD. The antioxidant activities of the litchi pulp extracts were determined by oxygen radical absorbance capacity (ORAC) and cellular antioxidant activity (CAA) assays. Results Of the solvents tested, aqueous acetone extracted the largest amount of total free phenolic compounds (210.7 mg GAE/100 g FW) from litchi pulp, followed sequentially by aqueous mixtures of methanol, ethanol and ethyl acetate, and water itself. The acid hydrolysis method released twice as many bound phenolic compounds as the alkaline hydrolysis method. Nine phenolic compounds were detected in the aqueous acetone extract. In contrast, not all of these compounds were found in the other four extracts. The classification and content of the bound phenolic compounds released by the acid hydrolysis method were higher than those achieved by the alkaline hydrolysis. The aqueous acetone extract showing the highest ORAC value (3406.9 μmol TE/100 g FW) for the free phenolic extracts. For the CAA method, however, the aqueous acetone and methanol extracts (56.7 and 55.1 μmol QE/100 g FW) showed the highest levels of activity of the five extracts tested. The ORAC and CAA values of the bound phenolic compounds obtained by acid hydrolysis were 2.6- and 1.9-fold higher than those obtained using the
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A Method to Estimate Free-Living Active and Sedentary Behavior from an Accelerometer
Lyden, Kate; Keadle, Sarah Kozey; Staudenmayer, John; Freedson, Patty S.
2013-01-01
Methods to estimate physical activity (PA) and sedentary behavior (SB) from wearable monitors need to be validated in free-living settings. PURPOSE The purpose of this study was to develop and validate two novel machine-learning methods (soj-1x and soj-3x) in a free-living setting. METHODS Participants were directly observed in their natural environment for ten consecutive hours on three separate occasions. PA and SB estimated from soj-1x, soj-3x and a neural network previously calibrated in the laboratory (lab-nnet) were compared to direct observation. RESULTS Compared to the lab-nnet, soj-1x and soj-3x improved estimates of MET-hours (lab-nnet: % bias (95% CI) = 33.1 (25.9, 40.4), rMSE = 5.4 (4.6, 6.2), soj-1x: % bias = 1.9 (−2.0, 5.9), rMSE = 1.0 (0.6, 1.3), soj-3x: % bias = 3.4 (0.0, 6.7), rMSE = 1.0 (0.6, 1.5)) and minutes in different intensity categories (lab-nnet: % bias = −8.2 (sedentary), −8.2 (light) and 72.8 (MVPA), soj-1x: % bias = 8.8 (sedentary), −18.5 (light) and −1.0 (MVPA), soj-3x: % bias = 0.5 (sedentary), −0.8 (light) and −1.0 (MVPA)). Soj-1x and soj-3x also produced accurate estimates of guideline minutes and breaks from sedentary time. CONCLUSION Compared to the lab-nnet algorithm, soj-1x and soj-3x improved the accuracy and precision in estimating free-living MET-hours, sedentary time, and time spent in light intensity activity and MVPA. Additionally, soj-3x is superior to soj-1x in differentiating sedentary behavior from light intensity activity. PMID:23860415
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Mediani, Ahmed; Abas, Faridah; Tan, Chin Ping; Khatib, Alfi
2014-05-07
The present study was conducted to determine the effect of air (AD), oven (OD) and freeze drying (FD) on the free radical scavenging activity and total phenolic content (TPC) of Cosmos caudatus and the effect of storage time by the comparison with a fresh sample (FS). Among the three drying methods that were used, AD resulted in the highest free radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) (IC50 = 0.0223 mg/mL) and total phenolic content (27.4 g GAE/100 g), whereas OD produced the lowest scavenging activity and TPC value. After three months of storage, the dried samples showed a high and consistent free radical scavenging activity when compared to stored fresh material. The drying methods could preserve the quality of C. caudatus during storage and the stability of its bioactive components can be maintained.
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Hetem, Robyn S; Mitchell, Duncan; de Witt, Brenda A; Fick, Linda G; Maloney, Shane K; Meyer, Leith C R; Fuller, Andrea
2018-05-31
As one of the few felids that is predominantly diurnal, cheetahs (Acinonyx jubatus Von Schreber, 1775) can be exposed to high heat loads in their natural habitat. Little is known about long-term patterns of body temperature and activity (including hunting) in cheetahs because long-term concurrent measurements of body temperature and activity never have been reported for cheetahs, or indeed for any free-living felid. We report here body temperature and locomotor activity measured with implanted data loggers over seven months in five free-living cheetahs in Namibia. Air temperature ranged from a maximum of 39ºC in summer to -2ºC in winter. Cheetahs had higher (∼0.4 ºC) maximum 24h body temperatures, later acrophase (∼1 h), with larger fluctuations in the range of the 24h body temperature rhythm (∼0.4 ºC) during a hot-dry period than during a cool-dry period, but maintained homeothermy irrespective of the climatic conditions. As ambient temperatures increased, the cheetahs shifted from a diurnal to a crepuscular activity pattern, with reduced activity between 9:00 and 15:00 and increased nocturnal activity. The timing of hunts followed the general pattern of activity; the cheetahs hunted when they were on the move. Cheetahs hunted if an opportunity presented itself, on occasion they hunted in the midday heat or in total darkness (new moon). Biologging revealed insights into cheetah biology that are not accessible by traditional observer-based techniques. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
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Characterization of oocyte retrieval cycles with empty zona pellucida.
Oride, Aki; Kanasaki, Haruhiko; Hara, Tomomi; Ohta, Hiroko; Kyo, Satoru
2018-01-01
To identify the factors that characterize cycles with empty zona pellucida (EZP). Thirty-six oocyte retrieval cycles from which EZP were collected and another 36 cycles from which no EZP was collected were compared. The patients were divided into three groups: those with no EZP collected during any cycle, those with EZP collected during all cycles, and those experiencing cycles both with and without EZP. The mean number of oocytes collected per cycle was higher in the cycles with EZP than without EZP. The fertilization rate of the collected oocytes and the rate of good embryo formation were significantly lower in the cycles with EZP. No significant difference was observed between the three groups in terms of age, number of oocytes collected, or hormone levels before and after the oocyte retrieval. The fertilization and pregnancy rates were highest in the patients with no EZP being collected during any cycle, followed by those experiencing cycles both with and without EZP, and then by those with EZP collected during all cycles. The observation of lower fertilization, poor embryo formation, and a low pregnancy rate in the patients with EZP suggests the poor quality of oocytes that were collected with EZP in the same cycle.
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ERIC Educational Resources Information Center
Karlsson, Fredrik; Olofsson, Katarina; Blomstedt, Patric; Linder, Jan; Nordh, Erik; van Doorn, Jan
2014-01-01
Purpose: The present study aimed at comparing the effects of deep brain stimulation (DBS) treatment of the subthalamic nucleus (STN) and the caudal zona incerta (cZi) on the proficiency in achieving oral closure and release during plosive production of people with Parkinson's disease. Method: Nineteen patients participated preoperatively and…
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Liu, Yue; Yang, Huiping; Torres, Leticia; Tiersch, Terrence R
2018-04-01
Knowledge of sperm motility activation for viviparous fishes has been limited to study of several species in Poeciliidae, and the dissociation of sperm bundles is even less understood. The goal of this study was to use the endangered Redtail Splitfin (Xenotoca eiseni) as a model to investigate the activation of sperm from viviparous fishes by study of free sperm and spermatozeugmata (unencapsulated sperm bundles). The specific objectives were to evaluate the effects of: (1) osmotic pressure and refrigerated storage (4 °C) on activation of free sperm, (2) osmotic pressure, ions, and pH on dissociation of spermatozeugmata, and (3) CaCl 2 concentration and pH on sperm membrane integrity. Free sperm were activated in Ca 2+ -free Hanks' balanced salt solution at 81-516 mOsmol/kg. The highest motility (19 ± 6%) was at 305 mOsmol/kg and swim remained for 84 h. Glucose (300-700 mOsmol/kg), NaCl (50-600 mOsmol/kg), and KCl, MgCl 2 , and MnCl 2 at 5-160 mM activated sperm within spermatozeugmata, but did not dissociate spermatozeugmata. CaCl 2 at 5-160 mM dissociated spermatozeugmata within 10 min. Solutions of NaCl-NaOH at pH 11.6 to 12.4 dissociated spermatozeugmata within 1 min. The percentage of viable cells had no significant differences (P = 0.2033) among different concentrations of CaCl 2 , but it was lower (P < 0.0001) at pH 12.5 than at pH between 7.0 and 12.0. Overall, this study provided a foundation for quality evaluation of sperm and spermatozeugmata from livebearing fishes, and for development of germplasm repositories for imperiled goodeids. Copyright © 2018 Elsevier Inc. All rights reserved.
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Li, Weiguang; Ge, Changhui; Yang, Liu; Wang, Ruixue; Lu, Yiming; Gao, Yan; Li, Zhihui; Wu, Yonghong; Zheng, Xiaofei; Wang, Zhaoyan; Zhang, Chenggang
2016-01-01
The bacterial protein flagellin is the known agonist of Toll-like receptor 5 (TLR5). It has been reported that CBLB502, a novel agonist of TLR5 derived from Salmonella flagellin, could reduce radiation toxicity in mouse and primate models, protect mice from dermatitis and oral mucositis caused by radiation, inhibit acute renal ischemic failure, and inhibit the growth of A549 lung cancer cell. The property of CBLB502 is able to bind to TLR5 and activates NF-κB signaling. In this study, we investigated the antioxidant potential and free radicals scavenging properties of CBLB502 in vitro. Interestingly, we found that CBLB502 has a direct and distinct antioxidant capacity and can efficiently scavenge a variety of free radicals, including superoxide anion, hydroxyl radical, and ABTS cation (ABTS(+)). Through wave scanning and kinetic evaluation of scavenging ABTS(+), we found that the ABTS(+) scavenging process of CBLB502 is relatively slow, and the ABTS(+) scavenging activity of CBLB502 has a consistently kinetics characteristics. In conclusion, our results suggested that CBLB502 has antioxidant and scavenging free radicals activities in vitro. It is implied that CBLB502 might partially promote the beneficial protective effect through its scavenging free radicals. Copyright © 2015. Published by Elsevier B.V.
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Pressman, Jonathan G; Lee, Woo Hyoung; Bishop, Paul L; Wahman, David G
2012-03-01
Chloramine has replaced free chorine for secondary disinfection at many water utilities because of disinfection by-product (DBP) regulations. Because chloramination provides a source of ammonia, there is a potential for nitrification when using chloramines. Nitrification in drinking water distribution systems is undesirable and may result in degradation of water quality and subsequent non-compliance with existing regulations. Thus, nitrification control is a major issue and likely to become increasingly important as chloramine use increases. In this study, monochloramine penetration and its effect on nitrifying biofilm activity, viability, and recovery was investigated and evaluated using microelectrodes and confocal laser scanning microscopy (CLSM). Monochloramine was applied to nitrifying biofilm for 24 h at two different chlorine to nitrogen (Cl(2):N) mass ratios (4:1 [4.4 mg Cl(2)/L] or 1:1 Cl(2):N [5.3 mg Cl(2)/L]), resulting in either a low (0.23 mg N/L) or high (4.2 mg N/L) free ammonia concentration. Subsequently, these biofilm samples were allowed to recover without monochloramine and receiving 4.2 mg N/L free ammonia. Under both monochloramine application conditions, monochloramine fully penetrated into the nitrifying biofilm within 24 h. Despite this complete monochloramine penetration, complete viability loss did not occur, and both biofilm samples subsequently recovered aerobic activity when fed only free ammonia. When monochloramine was applied with a low free ammonia concentration, dissolved oxygen (DO) fully penetrated, but with a high free ammonia concentration, complete cessation of aerobic activity (i.e., oxygen utilization) did not occur and subsequent analysis indicated that oxygen consumption still remained near the substratum. During the ammonia only recovery phase, different spatial recoveries were seen in each of the samples, based on oxygen utilization. It appears that the presence of higher free ammonia concentration allowed a
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Overview of free-piston Stirling SP-100 activities at the NASA Lewis Research Center
NASA Technical Reports Server (NTRS)
Slaby, J. G.
1986-01-01
An overview of the National Aeronautics and Space Administration (NASA) Lewis Research Center (LeRC) SP-100 free-piston Stirling engine activities is presented. These activities are being conducted in support of the Department of Defense (DOD), Department of Energy (DOE), and NASA. The space-power technology effort, under SP-100, addresses the status of the 25 kWe Space Power Demonstrator Engine (SPDE). Another facet of the SP-100 project covers the status of an endurance test. Dynamic balancing of the SPDE engine is discussed along with a summary covering the parametric results of a study showing the relationship between power-converter specific weight and efficiency both as a function of Stirling engine heater to cooler temperature ratio. Design parameters and conceptual design features are presented for a 25 kWe, single-cylinder free-piston Stirling space-power converter. And finally, a description of a hydrodynamic gas bearing concept is presented.
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Mediani, Ahmed; Abas, Faridah; Tan, Chin Ping; Khatib, Alfi
2014-01-01
The present study was conducted to determine the effect of air (AD), oven (OD) and freeze drying (FD) on the free radical scavenging activity and total phenolic content (TPC) of Cosmos caudatus and the effect of storage time by the comparison with a fresh sample (FS). Among the three drying methods that were used, AD resulted in the highest free radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) (IC50 = 0.0223 mg/mL) and total phenolic content (27.4 g GAE/100 g), whereas OD produced the lowest scavenging activity and TPC value. After three months of storage, the dried samples showed a high and consistent free radical scavenging activity when compared to stored fresh material. The drying methods could preserve the quality of C. caudatus during storage and the stability of its bioactive components can be maintained. PMID:26784876
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Andrabi, Nafeesa; Khoddam, Rubin; Leventhal, Adam M
2017-03-01
To examine whether reduced substance-free enjoyable activity (i.e., 'alternative reinforcers') is a mediating mechanism linking lower socioeconomic status and adolescent substance use risk. High school students in Los Angeles, CA (N = 2,553, 2013-2014, M age baseline = 14.1) were administered three semiannual surveys. Socioeconomic status was measured by highest parental education reported at Wave 1 (the beginning of 9th grade). Three elements of alternative reinforcement at Wave 2 (six-month follow-up) were assessed as mediators: ratings of frequency of engagement, level of enjoyment, and frequency × enjoyment product scores of substance-free typically pleasant activities (like participation in sports teams or school clubs). Study outcomes included prior six-month alcohol, marijuana, tobacco, and other substance use at Wave 3 (twelve-month follow-up). Logistic regression models adjusting for alternative reinforcers and substance use from the preceding wave as well as other co-factors were used to examine the association of Wave 1 parental education with Wave 3 substance use and mediation by Wave 2 alternative reinforcement. Lower parental education at Wave 1 was associated with a greater likelihood of reporting alcohol (β = -0.122, 95% CI = -0.234, -0.009) and marijuana (β = -0.168, 95% CI = -0.302, -0.034) use at Wave 3. The inverse association between parental education and substance use was statistically mediated by each element of diminished alternative reinforcement at Wave 2. Lower parental education at Wave 1 was associated with lower alternative reinforcement at Wave 2, which in turn was associated with greater likelihood of alcohol (range of β indirect effects : -0.007 [95% CI = -0.016, -0.001] to -0.01 [95% CI = -0.018, -0.004]) and marijuana (βs: -0.011 [95% CI = -0.022,-0.002] to -0.018 [95% CI = -0.035, -0.005]) use at Wave 3. Parental education was not associated with use of combustible tobacco products or other
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Ding, Hsiou-Yu
2011-01-01
The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity of the fruits of Rubus chingii was studied in vitro. Ethanolic extract, ethyl acetate and n-butanol fractions from dried R. chingii fruits revealed strong DPPH free radical scavenging activity with IC50 values of 17.9, 3.4 and 4.0 μg/mL, respectively. The ethyl acetate and n-butanol fractions were further purified by a combination of silica gel chromatography, Lobar RP-8 chromatography, and high-pressure liquid chromatography (HPLC). Nine compounds were isolated, where methyl (3-hydroxy-2-oxo-2,3-dihydroindol-3-yl)-acetate (2), vanillic acid (5), kaempferol (7), and tiliroside (9) showed stronger DPPH free radical scavenging activity than that of ascorbic acid (131.8 μM) with IC50 values of 45.2, 34.9, 78.5, and 13.7 μM, respectively. In addition, rubusine (1) is a new compound discovered in the present study and methyl (3-hydroxy-2-oxo-2,3-dihydroindol-3-yl)-acetate (2), methyl dioxindole-3-acetate (3), and 2-oxo-1,2-dihydroquinoline-4-carboxylic acid (4) were isolated from the fruits for the first time. PMID:21747716
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Oh, Mirae; Kim, Eun-Kyung; Jeon, Byong-Tae; Tang, Yujiao; Kim, Moon S; Seong, Hye-Jin; Moon, Sang-Ho
2016-09-01
The objective of this study was to evaluate chemical compositions, free amino acid contents, and antioxidant activities of different cuts of Hanwoo (Bos taurus coreanae) beef. Beef preferences and prices in the Korean market depend on cut. Therefore, comparisons were made between high-preference cuts (group 1 [G1], including loin, tenderloin, and rib) and low-preference cuts (group 2 [G2], including brisket, topside, and shank). Meat samples were collected from 10 fattened cows. Crude fat content was significantly higher in G1 than in G2 (p<0.05). The amounts of crude protein and total free amino acid were negatively correlated with crude fat content (p<0.05). Overall G2 contained higher levels of free amino acids with antioxidant activity than G1. Antioxidant activities were also significantly higher in G2 compared with G1 (p<0.05). In conclusion, providing consumers with positive information about G2 as found in this study could help health-conscious consumers choosing among beef products and further promote increased consumption of low-preference beef cuts. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Louros, Nikolaos N.; Iconomidou, Vassiliki A.; Giannelou, Polina; Hamodrakas, Stavros J.
2013-01-01
Zona pellucida (ZP) is an extracellular matrix surrounding and protecting mammalian and fish oocytes, which is responsible for sperm binding. Mammalian ZP consists of three to four glycoproteins, called ZP1, ZP2, ZP3, ZP4. These proteins polymerize into long interconnected filaments, through a common structural unit, known as the ZP domain, which consists of two domains, ZP-N and ZP-C. ZP is related in function to silkmoth chorion and in an evolutionary fashion to the teleostean fish chorion, also fibrous structures protecting the oocyte and embryo, that both have been proven to be functional amyloids. Two peptides were predicted as ‘aggregation-prone’ by our prediction tool, AMYLPRED, from the sequence of the human ZP1-N domain. Here, we present results from transmission electron microscopy, X-ray diffraction, Congo red staining and attenuated total reflectance Fourier-transform infrared spectroscopy (ATR FT-IR), of two synthetic peptide-analogues of these predicted ‘aggregation-prone’ parts of the human ZP1-N domain, that we consider crucial for ZP protein polymerization, showing that they both self-assemble into amyloid-like fibrils. Based on our experimental data, we propose that human ZP (hZP) might be considered as a novel, putative, natural protective amyloid, in close analogy to silkmoth and teleostean fish chorions. Experiments are in progress to verify this proposal. We also attempt to provide insights into ZP formation, proposing a possible model for hZP1-N domain polymerization. PMID:24069181
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Bystrom, Laura M; Lewis, Betty A; Brown, Dan L; Rodriguez, Eloy; Obendorf, Ralph L
2009-06-01
Edible fruits of the native South American tree Melicoccus bijugatus Jacq. are consumed fresh or in traditional food, drink and medicinal preparations. Some therapeutic effects of these fruits may be due to phenolics and sugars. Aqueous acetone, methanol or ethanol tissue extracts of different cultivars or collections of M. bijugatus fruits from the Dominican Republic and Florida were analyzed for total phenolics and free radical scavenging activity by UV-vis spectroscopy, sugars by gas chromatography, and antimicrobial activity by the disc diffusion assay. Total phenolics and free radical scavenging activities ranked: seed coat > embryo > pulp extracts. Montgomery cultivar fruits had the highest total phenolics. For sugars: pulp > embryo and highest in Punta Cana fruit pulp. In all extracts: sucrose > glucose and fructose. Glucose:fructose ratios were 1:1 (pulp) and 0.2:1 (embryo). Pulp extracts had dose-response antibacterial activity and pulp and embryo extracts had antifungal activity against one yeast species. Phenolics and sugars were confirmed with thin-layer chromatography and nuclear magnetic resonance. Sugar-free pulp fractions containing phenolics had slightly more antimicrobial activity than H2O-soluble pulp fractions with sugars. Results indicate M. bijugatus fruits contain phenolics, sugars and other H2O-soluble compounds consistent with therapeutic uses.
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Capital social de los padres de escolares de una zona vulnerable.
Cornejo, Susana; Herrera, Ariel; Hilas, Elena; Gigena, Y Pablo
2018-01-01
El capital social supone importantes inversiones materiales, simbólicas y de esfuerzos. Conocer el capital social de una comunidad puede facilitar la comprensión del beneficio de las relaciones comunitarias para la promoción de salud. Con el objetivo de reconocer los componentes del capital social de padres de escolares atendiendo una escuela en una zona vulnerable de la ciudad de Córdoba, Argentina, indagamos a través de grupos focales acerca de elementos esenciales del capital social. La asintonía socio-cultural entre los pobladores originarios y los reubicados, la estigmatización policial y el clientelismo político han generado desconfianza del uno hacia el otro en diferentes aspectos convivenciales, siendo la familia la única red de apoyo. La escuela se reconoce como espacio adonde la gente espontáneamente se organiza para invertir en redes sociales, presentándose así con potencialidad para la promoción de conductas saludables, por el lugar simbólico que ocupa para los padres.
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NASA Astrophysics Data System (ADS)
Delavault, Stéphanie; Prieur, Pascal; Liénart, Thomas; Robert, Alain; Guidotti, Pierre-Yves
2018-04-01
Microscope is a CNES-ESA-ONERA-CNRS-OCA-DLR-ZARM mission dedicated to the test of the Equivalence Principle with an improved accuracy of 10-15. The 300 kg drag-free microsatellite was launched on April 25th 2016 into a 710 km dawndusk sun-synchronous orbit for a 2-year mission. To comply with stringent requirements, the drag-free and attitude control system (DFACS) involves the scientific accelerometer as main sensor and a set of 8 cold gas proportional thrusters. Once in mission mode, within the CNES drag-free expertise center (CECT) the DFACS team provides several services to the system and to the scientific mission center: cold gas monitoring and management, `Attitude' ancillary data, DFACS expertise ancillary data. For this purpose, expertise tools have been implemented in the CECT, using the flexibility and efficiency of Matlab™ utilities. This paper presents the role of the CECT within the mission and details the expertise activities of the DFACS team illustrated with some typical in flight results.
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Harinipriya, S; Sangaranarayanan, M V
2006-01-31
The evaluation of the free energy of activation pertaining to the electron-transfer reactions occurring at liquid/liquid interfaces is carried out employing a diffuse boundary model. The interfacial solvation numbers are estimated using a lattice gas model under the quasichemical approximation. The standard reduction potentials of the redox couples, appropriate inner potential differences, dielectric permittivities, as well as the width of the interface are included in the analysis. The methodology is applied to the reaction between [Fe(CN)6](3-/4-) and [Lu(biphthalocyanine)](3+/4+) at water/1,2-dichloroethane interface. The rate-determining step is inferred from the estimated free energy of activation for the constituent processes. The results indicate that the solvent shielding effect and the desolvation of the reactants at the interface play a central role in dictating the free energy of activation. The heterogeneous electron-transfer rate constant is evaluated from the molar reaction volume and the frequency factor.
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Canosa, S; Adriaenssens, T; Coucke, W; Dalmasso, P; Revelli, A; Benedetto, C; Smitz, J
2017-05-01
Do the mRNA expression levels of zona pellucida (ZP) genes, ZP1, 2, 3 and 4 in oocyte and cumulus cells (CC) reveal relevant information on the oocyte? The ZP mRNA expression in human oocytes is related to oocyte maturity, zona inner layer (IL) retardance and fertilization capacity. ZP structure and birefringence provide useful information on oocyte cytoplasmic maturation, developmental competence for embryonic growth, blastocyst formation and pregnancy. In order to understand the molecular basis of morphological changes in the ZP, in the current study, the polarized light microscopy (PLM) approach was combined with analysis of the expression of the genes encoding ZP1, 2, 3 and 4, both in the oocytes and in the surrounding CC. This is a retrospective study comprising 98 supernumerary human cumulus oocyte complexes (COC) [80 Metaphase II (MII), 10 Metaphase I (MI) and 8 germinal vesicle (GV)] obtained from 39 patients (median age 33.4 years, range 22-42) after controlled ovarian stimulation. Single oocytes and their corresponding CC were analysed. Oocytes were examined using PLM, and quantitative RT-PCR was performed for ZP1, 2, 3 and 4 in these individual oocytes and their CC. Ephrin-B2 (EFNB2) mRNA was measured in CC as a control. Presence of ZP3 protein in CC and oocytes was investigated using immunocytochemistry. Data were analysed using one-parametric and multivariate analysis and were corrected for the potential impact of patient and cycle characteristics. Oocytes contained ZP1/2/3 and 4 mRNA while in CC only ZP3 was quantifiable. Also ZP3 protein was detected in human CC. When comparing mature (MII) and immature oocytes (MI/GV) or their corresponding CC, ZP1/2 and 4 expression was lower in mature oocytes compared to the expression in immature oocytes (all P < 0.05) and ZP3 expression was lower in the CC of mature oocytes compared to the expression in CC of immature oocytes (P < 0.05). This coincided with a significantly smaller IL-ZP area and thickness in
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Kolodziejczyk-Czepas, Joanna; Nowak, Pawel; Kowalska, Iwona; Stochmal, Anna
2014-10-01
Clovers were chosen on the basis of traditional medicine recommendations, agricultural value, or available information on their promising chemical profiles. This study evaluates and compares free radical scavenging and antioxidant properties of six clover species: Trifolium alexandrinum L. (Leguminosae), Trifolium fragiferum L., Trifolium hybridum L., Trifolium incarnatum L., Trifolium resupinatum var. majus Boiss., and Trifolium resupinatum var. resupinatum L. Free radical scavenging activity of the extracts (1.5-50 µg/ml) was estimated by reduction of 1,1-diphenyl-2-picrylhydrazyl (DPPH(•)) and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic) acid (ABTS(•)) radicals. The Trifolium extract effects on total antioxidant capacity of blood plasma were determined by the reduction of ABTS(•+) and DPPH(•) radicals, as well as with the use of the ferric reducing ability of plasma (FRAP) assay. The UPLC analysis of chemical profiles of the examined extracts showed the presence of three or four groups of phenolic substances, including phenolic acids, clovamides, isoflavones, and other flavonoids. The measurements of free radical scavenging and ferric reducing ability of the examined clover extracts revealed the strongest effect for T. alexandrinum. Furthermore, antioxidant activity assays in human plasma have shown protective effects of all extracts against peroxynitrite-induced reduction of total antioxidant capacity. Trifolium plants may be a rich source of bioactive substances with antioxidant properties. The examined extracts displayed free radical scavenging action and partly protected blood plasma against peroxynitrite-induced oxidative stress; however, the beneficial effects of T. alexandrinum and T. incarnatum seem to be slightly higher.
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Marrone, Sonia; Plume, Jessica White; Kerr, Patrick; Pignol, Anna; Vogeltanz-Holm, Nancy; Holm, Jeffrey; Larsen, Margo Adams
2009-01-01
Medical management for children with type 1 diabetes mellitus, including insulin administration to control high blood glucose levels (BGL), is crucial. However, a child-controlled behavioural strategy, like physical activity, to maintain target BGL may be warranted. To demonstrate, pre- and post-activity BGL were collected for 73 children aged 8- to 14-years attending a diabetes camp. Change in BGL across one session of a free-play swimming activity was analysed. Average BGL was significantly reduced from 197.18 mg/dl to 177.78 mg/dl across one 45 min session, and male gender predicted larger reductions. With safety precautions and within the context of appropriate medical management, free-play activity could be used as a strategy for maintaining target BGL.
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2015-01-01
Background Selection of the best oocyte for subsequent steps of fertilization and embryo transfer was shown to be the crucial step in human infertility treatment procedure. Oocyte selection using morphological criteria mainly Zona pellucida (ZP) has been the gold standard method in assisted reproductive technologies (ART) clinics, but this selection approach has limitations in terms of accuracy, objectivity and constancy. Recent studies using OMICs-based approaches have allowed the identification of key molecular markers that quantitatively and non-invasively predict the oocyte quality for higher pregnancy rates and efficient infertility treatment. These biomarkers are a valuable reinforcement of the morphological selection criteria widely used in in vitro fertilization (IVF) clinics. In this context, this study was designed to investigate the relationship between transcriptomic predictors of oocyte quality found by our group and the conventional morphological parameters of oocyte quality mainly the ZP birefringence. Results Microarray data revealed that 48 and 27 differentially expressed candidate genes in cumulus cells (CCs) were respectively overexpressed and underexpressed in the ZGP (Zona Good Pregnant) versus ZBNP (Zona Bad Non Pregnant) groups. More than 70% of previously reported transcriptomic biomarkers of oocyte developmental competence were confirmed in this study. The analysis of possible association between ZP birefringence versus molecular markers approach showed an absence of correlation between them using the current set of markers. Conclusions This study suggested a new integrative approach that matches morphological and molecular approaches used to select developmentally competent oocytes able to lead to successful pregnancy and the delivery of healthy baby. For each ZP birefringence score, oocytes displayed a particular CCs' gene expression pattern. However, no correlations were found between the 7 gene biomarkers of oocyte developmental
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Component analysis and free radicals scavenging activity of Cicer arietinum L. husk pectin.
Urias-Orona, Vania; Huerta-Oros, Joselina; Carvajal-Millán, Elizabeth; Lizardi-Mendoza, Jaime; Rascón-Chu, Agustin; Gardea, Alfonso A
2010-10-11
A pectin (CAP) was extracted from the husk of Cicer arietinum L. Monosaccharide analysis of CAP revealed the dominance of galacturonic acid and smaller amounts of galactose, arabinose, rhamnose, glucose, xylose and mannose. Viscosimetric analysis showed that the intrinsic viscosity ([η]) and the molecular weight (MW) of CAP were 296 mL/g and 105 kDa, respectively. The degree of esterification (DE = 10%) was determined by FTIR spectroscopy. CAP exhibited a dose-dependent free radical scavenging activity, as shown by its DPPH radical inhibition. At 1.0 mg/mL CAP exhibited a scavenging rate of 29% on DPPH radicals. The evaluation of antioxidant activity suggested that CAP had good potential for DPPH radical scavenging activity and should be explored as a novel potential antioxidant.
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Koubová, Eva; Mrázková, Martina; Sumczynski, Daniela; Orsavová, Jana
2018-06-01
Total phenolic content, phenolic profile and antioxidant activity were determined in free and bound phenolic fractions of thermally treated brown and white teff grains. Phenolic content in raw brown and white teff (1540 and 992 mg gallic acid equivalent kg -1 ) as well as antioxidant activity (6.3 and 5.5 mmol trolox equivalent kg -1 ) were higher in free phenolic fractions. The most significant decrease in total phenolics was observed after application of the sous-vide method (35% for brown teff and 11% for white teff). Main free phenolics of heat-treated teff were ferulic, protocatechuic, p-coumaric and ellagic acids, rutin and epigallocatechin. Main bound phenolics were ferulic, gallic, sinapic and ellagic acids, catechin and epigallocatechin. The detrimental effect on free and bound quercetin and bound cinnamic acid concentrations was also examined during heat treatment. Thermally treated brown teff showed a high level of in vitro organic matter digestibility if water cooking and rice cooker (both 99.5%) and sous-vide (96.5%) methods were applied. The sous-vide method may be recommended as the most suitable hydrothermal treatment for grains of teff when compared with water cooking and rice cooker methods. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.
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VEGF secretion during hypoxia depends on free radicals-induced Fyn kinase activity in mast cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Garcia-Roman, Jonathan; Ibarra-Sanchez, Alfredo; Lamas, Monica
2010-10-15
Research highlights: {yields} Bone marrow-derived mast cells (BMMCs) secrete functional VEGF but do not degranulate after Cobalt chloride-induced hypoxia. {yields} CoCl{sub 2}-induced VEGF secretion in mast cells occurs by a Ca{sup 2+}-insensitive but brefeldin A and Tetanus toxin-sensitive mechanism. {yields} Trolox and N-acetylcysteine inhibit hypoxia-induced VEGF secretion but only Trolox inhibits Fc{epsilon}RI-dependent anaphylactic degranulation in mast cells. {yields} Src family kinase Fyn activation after free radical production is necessary for hypoxia-induced VEGF secretion in mast cells. -- Abstract: Mast cells (MC) have an important role in pathologic conditions such as asthma and chronic obstructive pulmonary disease (COPD), where hypoxia conducemore » to deleterious inflammatory response. MC contribute to hypoxia-induced angiogenesis producing factors such as vascular endothelial growth factor (VEGF), but the mechanisms behind the control of hypoxia-induced VEGF secretion in this cell type is poorly understood. We used the hypoxia-mimicking agent cobalt chloride (CoCl{sub 2}) to analyze VEGF secretion in murine bone marrow-derived mast cells (BMMCs). We found that CoCl{sub 2} promotes a sustained production of functional VEGF, able to induce proliferation of endothelial cells in vitro. CoCl{sub 2}-induced VEGF secretion was independent of calcium rise but dependent on tetanus toxin-sensitive vesicle-associated membrane proteins (VAMPs). VEGF exocytosis required free radicals formation and the activation of Src family kinases. Interestingly, an important deficiency on CoCl{sub 2}-induced VEGF secretion was observed in Fyn kinase-deficient BMMCs. Moreover, Fyn kinase was activated by CoCl{sub 2} in WT cells and this activation was prevented by treatment with antioxidants such as Trolox and N-acetylcysteine. Our results show that BMMCs are able to release VEGF under hypoxic conditions through a tetanus toxin-sensitive mechanism, promoted by free
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Sternkopf Lillebæk, Eva Maria; Lambert Nielsen, Stine; Scheel Thomasen, Rikke; Færgeman, Nils J; Kallipolitis, Birgitte H
The foodborne pathogen Listeria monocytogenes is the causative agent of the invasive disease listeriosis. Infection by L. monocytogenes involves bacterial crossing of the intestinal barrier and intracellular replication in a variety of host cells. The PrfA protein is the master regulator of virulence factors required for bacterial entry, intracellular replication and cell-to-cell spread. PrfA-dependent activation of virulence genes occurs primarily in the blood and during intracellular infection. In contrast, PrfA does not play a significant role in regulation of virulence gene expression in the intestinal environment. In the gastrointestinal phase of infection, the bacterium encounters a variety of antimicrobial agents, including medium- and long-chain free fatty acids that are commonly found in our diet and as active components of bile. Here we show that subinhibitory concentrations of specific antimicrobial free fatty acids act to downregulate transcription of PrfA-activated virulence genes. Interestingly, the inhibitory effect is also evident in cells encoding a constitutively active variant of PrfA. Collectively, our data suggest that antimicrobial medium- and long-chain free fatty acids may act as signals to prevent PrfA-mediated activation of virulence genes in environments where PrfA activation is not required, such as in food and the gastrointestinal tract. Copyright © 2017 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.
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Quantifying Equid Behavior - A Research Ethogram for Free-Roaming Feral Horses
Ransom, Jason I.; Cade, Brian S.
2009-01-01
Feral horses (Equus caballus) are globally distributed in free-roaming populations on all continents except Antarctica and occupy a wide range of habitats including forest, grassland, desert, and montane environments. The largest populations occur in Australia and North America and have been the subject of scientific study for decades, yet guidelines and ethograms for feral horse behavioral research are largely absent in the scientific literature. The U.S. Geological Survey (USGS) Fort Collins Science Center conducted research on the influences of the immunocontraceptive porcine zona pellucida (PZP) on feral horse behavior from 2003-2006 in three discrete populations in the American west. These populations were the Little Book Cliffs Wild Horse Range in Colorado, McCullough Peaks Herd Management Area in Wyoming, and Pryor Mountain Wild Horse Range in Montana; the research effort included over 1,800 hours of behavioral observations of 317 adult free-roaming feral horses. An ethogram was developed during the course of this study to facilitate accurate scientific data collection on feral horse behavior, which is often challenging to quantify. By developing this set of discrete behavioral definitions and a set of strict research protocols, scientists were better able to address both applied questions, such as behavioral changes related to fertility control, and theoretical questions, such as understanding networks and dominance hierarchies within social groups of equids.
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Li, Zhi-Qiang; Liu, Bing-Rong; Zeng, Wen-Hui; Xiao, Wei-Liang; Li, Qiu-Jian; Zhong, Jun-Hong
2013-01-01
Cellulose digestion in termites (Isoptera) is highly important for ecological reasons and applications in biofuel conversion. The speciose Termitidae family has lost flagellates in the hindgut and developed diverse feeding habits. To address the response of cellulase activity to the differentiation of feeding habits, a comparative study of the activity and distribution of composite cellulases, endo-β-1,4-glucanase, and β-glucosidase was performed in seven common flagellate-free termites with three feeding habits: the humus-feeding termites Sinocapritermes mushae (Oshima et Maki), Malaysiocapritermes zhangfengensis Zhu, Yang et Huang and Pericapritermes jiangtsekiangensis (Kemner); the fungus-growing termites Macrotermes barneyi Light and Odontotermes formosanus (Shiraki); and the wood-feeding termites Nasutitermes parvonasutus (Shiraki) and Havilanditermes orthonasus (Tsai et Chen). The results showed that in diverse feeding groups, the wood-feeding group had the highest total composite cellulase and endo-β-1,4-glucanase activities, while the fungus-growing group had the highest β-glucosidase activity. In terms of the distribution of cellulase activity in the alimentary canals, the cellulase activities in wood-feeding termites were concentrated in the midgut, but there was no significant difference between all gut segments in humus-feeding termites. As for the fungus-growing termites, the main site of composite cellulase activity was in the midgut. The endo-β-1,4-glucanase activity was restricted to the midgut, but the primary site of β-glucosidase activity was in the foregut and the midgut (Mac. barneyi). The functions of the gut segments apparently differentiated between feeding groups. The results suggest that the differentiation of feeding habits in flagellate-free termites was characterized by the distribution of cellulases in the gut rather than by variations in cellulase activity.
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Li, Zhi-Qiang; Liu, Bing-Rong; Zeng, Wen-Hui; Xiao, Wei-Liang; Li, Qiu-Jian; Zhong, Jun-Hong
2013-01-01
Cellulose digestion in termites (Isoptera) is highly important for ecological reasons and applications in biofuel conversion. The speciose Termitidae family has lost flagellates in the hindgut and developed diverse feeding habits. To address the response of cellulase activity to the differentiation of feeding habits, a comparative study of the activity and distribution of composite cellulases, endo-β-1, 4-glucanase, and β-glucosidase was performed in seven common flagellate-free termites with three feeding habits: the humus-feeding termites Sinocapritermes mushae (Oshima et Maki), Malaysiocapritermes zhangfengensis Zhu, Yang et Huang and Pericapritermes jiangtsekiangensis (Kemner); the fungus-growing termites Macrotermes barneyi Light and Odontotermes formosanus (Shiraki); and the wood-feeding termites Nasutitermes parvonasutus (Shiraki) and Havilanditermes orthonasus (Tsai et Chen). The results showed that in diverse feeding groups, the wood-feeding group had the highest total composite cellulase and endo-β-1, 4-glucanase activities, while the fungus-growing group had the highest β-glucosidase activity. In terms of the distribution of cellulase activity in the alimentary canals, the cellulase activities in wood-feeding termites were concentrated in the midgut, but there was no significant difference between all gut segments in humus-feeding termites. As for the fungus-growing termites, the main site of composite cellulase activity was in the midgut. The endo-β-1, 4-glucanase activity was restricted to the midgut, but the primary site of β-glucosidase activity was in the foregut and the midgut (Mac. barneyi). The functions of the gut segments apparently differentiated between feeding groups. The results suggest that the differentiation of feeding habits in flagellate-free termites was characterized by the distribution of cellulases in the gut rather than by variations in cellulase activity. PMID:23895662
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Free energy landscape of activation in a signaling protein at atomic resolution
Pontiggia, F.; Pachov, D.V.; Clarkson, M.W.; Villali, J.; Hagan, M.F.; Pande, V.S.; Kern, D.
2015-01-01
The interconversion between inactive and active protein states, traditionally described by two static structures, is at the heart of signaling. However, how folded states interconvert is largely unknown due to the inability to experimentally observe transition pathways. Here we explore the free energy landscape of the bacterial response regulator NtrC by combining computation and NMR, and discover unexpected features underlying efficient signaling. We find that functional states are defined purely in kinetic and not structural terms. The need of a well-defined conformer, crucial to the active state, is absent in the inactive state, which comprises a heterogeneous collection of conformers. The transition between active and inactive states occurs through multiple pathways, facilitated by a number of nonnative transient hydrogen bonds, thus lowering the transition barrier through both entropic and enthalpic contributions. These findings may represent general features for functional conformational transitions within the folded state. PMID:26073309
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Antibacterial free fatty acids: activities, mechanisms of action and biotechnological potential.
Desbois, Andrew P; Smith, Valerie J
2010-02-01
Amongst the diverse and potent biological activities of free fatty acids (FFAs) is the ability to kill or inhibit the growth of bacteria. The antibacterial properties of FFAs are used by many organisms to defend against parasitic or pathogenic bacteria. Whilst their antibacterial mode of action is still poorly understood, the prime target of FFA action is the cell membrane, where FFAs disrupt the electron transport chain and oxidative phosphorylation. Besides interfering with cellular energy production, FFA action may also result from the inhibition of enzyme activity, impairment of nutrient uptake, generation of peroxidation and auto-oxidation degradation products or direct lysis of bacterial cells. Their broad spectrum of activity, non-specific mode of action and safety makes them attractive as antibacterial agents for various applications in medicine, agriculture and food preservation, especially where the use of conventional antibiotics is undesirable or prohibited. Moreover, the evolution of inducible FFA-resistant phenotypes is less problematic than with conventional antibiotics. The potential for commercial or biomedical exploitation of antibacterial FFAs, especially for those from natural sources, is discussed.
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Literacy as a leisure activity: free-time preferences of older children and young adolescents.
Nippold, Marilyn A; Duthie, Jill K; Larsen, Jennifer
2005-04-01
Literacy plays an important role in the development of language in school-age children and adolescents. For example, by reading a variety of books, magazines, and newspapers, students gain exposure to complex vocabulary, and reading becomes a prime opportunity for learning new words. Despite the importance of reading for lexical development, little is known about the pleasure reading habits of today's youth. The first goal of this investigation was to examine the preferences of older children and young adolescents with respect to reading as a leisure-time activity and its relationship to other free-time options that are likely to compete for their attention. The second goal was to examine the amount of time that young people spend reading for pleasure each day and the types of materials they most enjoy reading. The third goal was to determine if preferences for free-time activities and reading materials would evince age- and gender-related differences during the period of development from late childhood through early adolescence (ages 11-15 years). The findings could serve as a reference point for understanding what is reasonable to expect of students during this age range. The participants were 100 sixth graders (mean age = 11;7 [years; months]) and 100 ninth graders (mean age = 14;8) attending public schools in western Oregon. Each group contained an equal number of boys and girls, all of whom spoke English as their primary language and were considered to be typical achievers. All participants completed a survey concerning their preferred free-time activities and reading materials. They also reported the average amount of time they spent reading for pleasure each day. The most popular free-time activities were listening to music/going to concerts, watching television or videos, playing sports, and playing computer or video games. Least preferred activities were cooking, running or walking, writing, and arts and crafts. Reading was moderately popular. The most
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Control of C-H Bond Activation by Mo-Oxo Complexes: pKa or Bond Dissociation Free Energy (BDFE)?
Nazemi, Azadeh; Cundari, Thomas R
2017-10-16
A density functional theory (DFT) study (BMK/6-31+G(d)) was initiated to investigate the activation of benzylic carbon-hydrogen bonds by a molybdenum-oxo complex with a potentially redox noninnocent supporting ligand-a simple mimic of the active species of the enzyme ethylbenzene dehydrogenase (EBDH)-through deprotonation (C-H bond heterolysis) or hydrogen atom abstraction (C-H bond homolysis) routes. Activation free-energy barriers for neutral and anionic Mo-oxo complexes were high, but lower for anionic complexes than neutral complexes. Interesting trends as a function of substituents were observed that indicated significant H δ+ character in the transition states (TS), which was further supported by the preference for [2 + 2] addition over HAA for most complexes. Hence, it was hypothesized that C-H activation by these EBDH mimics is controlled more by the pK a than by the bond dissociation free energy of the C-H bond being activated. Therefore, the results suggest promising pathways for designing more efficient and selective catalysts for hydrocarbon oxidation based on EBDH active-site mimics.
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Fan, Jiang Ping; Fan, Chong; Dong, Wen Min; Gao, Bin; Yuan, Wei; Gong, Jia Shun
2013-09-01
An ethanol-soluble pigment extract was separated from fermented Zijuan Pu-erh tea. The compositions of the ethanol soluble pigment extract were analyzed by high-performance liquid chromatography-tandem mass spectroscopy (HPLC-MS/MS). The extract was prepared into a series of ethanol solutions and analyzed for free radical-scavenging activities (against two free radicals: 1,1-diphenyl-2-picrylhydrazyl (DPPH) and (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO)) and in vitro anti-oxidative properties. Electron spin resonance spectroscopy showed that the peaks of DPPH and TEMPO decreased with increasing extract concentration, suggesting that the extract had excellent free radical-scavenging activities. In vitro cell culture suggested that, at 50-200 mg/L, the extract had no measurable effect on the viability of vascular endothelial cells (ECV340) but produced significant protective effects for cells that underwent oxidative injuries due to hydrogen peroxide (H₂O₂) treatment. Compared with the H₂O₂ treatment alone cells group, 200 mg/L of the extract increased the activity of superoxide dismutase (SOD) in cells by 397.3%, and decreased the concentration of malondialdehyde (MDA) and the activity of lactate acid dehydrogenase (LDH) by 47.8% and 69.6%, respectively. These results suggest that the extract has excellent free radical scavenging and anti-oxidative properties. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Swallowing Quality of Life After Zona Incerta Deep Brain Stimulation.
Sundstedt, Stina; Nordh, Erik; Linder, Jan; Hedström, Johanna; Finizia, Caterina; Olofsson, Katarina
2017-02-01
The management of Parkinson's disease (PD) has been improved, but management of signs like swallowing problems is still challenging. Deep brain stimulation (DBS) alleviates the cardinal motor symptoms and improves quality of life, but its effect on swallowing is not fully explored. The purpose of this study was to examine self-reported swallowing-specific quality of life before and after caudal zona incerta DBS (cZI DBS) in comparison with a control group. Nine PD patients (2 women and 7 men) completed the self-report Swallowing Quality of Life questionnaire (SWAL-QOL) before and 12 months after cZI DBS surgery. The postoperative data were compared to 9 controls. Median ages were 53 years (range, 40-70 years) for patients and 54 years (range, 42-72 years) for controls. No significant differences were found between the pre- or postoperative scores. The SWAL-QOL total scores did not differ significantly between PD patients and controls. The PD patients reported significantly lower scores in the burden subscale and the symptom scale. Patients with PD selected for cZI DBS showed good self-reported swallowing-specific quality of life, in many aspects equal to controls. The cZI DBS did not negatively affect swallowing-specific quality of life in this study.
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Almeida, Gustavo J; Irrgang, James J; Fitzgerald, G Kelley; Jakicic, John M; Piva, Sara R
2016-06-01
Few instruments that measure physical activity (PA) can accurately quantify PA performed at light and moderate intensities, which is particularly relevant in older adults. The evidence of their reliability in free-living conditions is limited. The study objectives were: (1) to determine the test-retest reliability of the Actigraph (ACT), SenseWear Armband (SWA), and Community Healthy Activities Model Program for Seniors (CHAMPS) questionnaire in assessing free-living PA at light and moderate intensities in people after total knee arthroplasty; (2) to compare the reliability of the 3 instruments relative to each other; and (3) to determine the reliability of commonly used monitoring time frames (24 hours, waking hours, and 10 hours from awakening). A one-group, repeated-measures design was used. Participants wore the activity monitors for 2 weeks, and the CHAMPS questionnaire was completed at the end of each week. Test-retest reliability was determined by using the intraclass correlation coefficient (ICC [2,k]) to compare PA measures from one week with those from the other week. Data from 28 participants who reported similar PA during the 2 weeks were included in the analysis. The mean age of these participants was 69 years (SD=8), and 75% of them were women. Reliability ranged from moderate to excellent for the ACT (ICC=.75-.86) and was excellent for the SWA (ICC=.93-.95) and the CHAMPS questionnaire (ICC=.86-.92). The 95% confidence intervals (95% CI) of the ICCs from the SWA were the only ones within the excellent reliability range (.85-.98). The CHAMPS questionnaire showed systematic bias, with less PA being reported in week 2. The reliability of PA measures in the waking-hour time frame was comparable to that in the 24-hour time frame and reflected most PA performed during this period. Reliability may be lower for time intervals longer than 1 week. All PA measures showed good reliability. The reliability of the ACT was lower than those of the SWA and the CHAMPS
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Li, Qing; Sun, Xueqi; Gu, Guodong
2018-01-01
Chitosan is an abundant and renewable polysaccharide, which exhibits attractive bioactivities and natural properties. Improvement such as chemical modification of chitosan is often performed for its potential of providing high bioactivity and good water solubility. A new class of chitosan derivatives possessing 1,2,3-triazolium charged units by associating “click reaction” with efficient 1,2,3-triazole quaternization were designed and synthesized. Their free radical-scavenging activity against three free radicals was tested. The inhibitory property and water solubility of the synthesized chitosan derivatives exhibited a remarkable improvement over chitosan. It is hypothesized that triazole or triazolium groups enable the synthesized chitosan to possess obviously better radical-scavenging activity. Moreover, the scavenging activity against superoxide radical of chitosan derivatives with triazolium (IC50 < 0.01 mg mL−1) was more efficient than that of derivatives with triazole and Vitamin C. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radical-scavenging assay, the same pattern were observed, which should be related to the triazolium grafted at the periphery of molecular chains. PMID:29597269
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Li, Qing; Sun, Xueqi; Gu, Guodong; Guo, Zhanyong
2018-03-28
Chitosan is an abundant and renewable polysaccharide, which exhibits attractive bioactivities and natural properties. Improvement such as chemical modification of chitosan is often performed for its potential of providing high bioactivity and good water solubility. A new class of chitosan derivatives possessing 1,2,3-triazolium charged units by associating "click reaction" with efficient 1,2,3-triazole quaternization were designed and synthesized. Their free radical-scavenging activity against three free radicals was tested. The inhibitory property and water solubility of the synthesized chitosan derivatives exhibited a remarkable improvement over chitosan. It is hypothesized that triazole or triazolium groups enable the synthesized chitosan to possess obviously better radical-scavenging activity. Moreover, the scavenging activity against superoxide radical of chitosan derivatives with triazolium (IC 50 < 0.01 mg mL -1 ) was more efficient than that of derivatives with triazole and Vitamin C. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radical-scavenging assay, the same pattern were observed, which should be related to the triazolium grafted at the periphery of molecular chains.
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Hu, Qiaobin; Wang, Taoran; Zhou, Mingyong; Xue, Jingyi; Luo, Yangchao
2016-07-27
The major objective of this work was to develop a green and facile process to prepare gallic acid-chitosan conjugate and comprehensively evaluate the physicochemical properties and biological activities of an as-prepared water-soluble chitosan derivative. A free-radical-induced grafting approach using an ascorbic acid-hydrogen peroxide redox pair was adopted. The obtained conjugate was characterized by Fourier transform infrared spectroscopy, UV-vis, X-ray diffraction, and pKa analysis. The antioxidant activities were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6)-sulphonic acid (ABTS), reducing power, and oxygen-radical antioxidant-capacity assays. The results showed that the mass ratio of gallic acid to chitosan played a vital role in determining the grafting degree and ζ potential of the conjugates, with the ratio of 0.5:1 being the optimal ratio that resulted in the highest grafting degree. The antioxidant assays demonstrated that conjugation significantly improved the antioxidant activities, being dramatically higher than that of free chitosan. It was notable that the DPPH- and ABTS-scavenging activities of conjugate at 0.4 mg/mL reached the same level as the free gallic acid at the equivalent concentration. Our study demonstrated a green and facile synthesis approach to preparing a novel water-soluble chitosan derivative that may have promising potentials in the food industry.
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Thivat, Emilie; Durando, Xavier; Demidem, Aïcha; Farges, Marie-Chantal; Rapp, Maryse; Cellarier, Eric; Guenin, Samuel; D'Incan, Michel; Vasson, Marie-Paule; Chollet, Philippe
2007-01-01
Methionine (MET) depletion used in association with chemotherapy improves the therapeutic index in animal models. This potentiating effect may be due to tumor cell sensitization to chloroethylnitrosoureas through their MET dependency and the down-regulation of O6- methylguanine-DNA methyltransferase (MGMT). Our purpose was to evaluate the impact of the association of a dietary MET restriction with nitrosourea treatment on MGMT activity in peripheral blood mononuclear cells (PBMCs). Six patients with metastatic cancer (melanoma and glioma) received 4 cycles of a MET-free diet with cystemustine (60 mg/m2). MGMT activity in PBMCs decreased by an average of 13% from 553+/-90 fnol/mg before the diet to 413+/-59 fmol/mg after the diet + chemotherapy period (p=0.029). The decrease of MGMT activity was not affected by the duration of the MET-free diet period but seems to be correlated to the plasma MET depletion induced by the MET-free diet.
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Custodio, William; Silva, Wander J; Paes Leme, Adriana F; Cury, Jaime A; Del Bel Cury, Altair A
2015-11-01
The objective of the present study was to determine if blood plasma proteins could change the proteome of the acquired denture pellicle by label-free quantitative proteomics. As pellicle proteome modulates the interaction between substrates and Candida cells, we investigated its effect on the surface free energy (SFE) of the coated resin and on Candida albicans phospholipase and aspartyl proteinase activities. Poly(methylmethacrylate) discs were exposed to saliva (control) or saliva enriched with blood plasma (experimental group). The pellicle proteome was analyzed by mass spectrometry coupled with liquid chromatography. SFE was determined by acid-base technique. After biofilm formation, phospholipase and proteinase activities were determined accordingly to classic plate methods. Data were analyzed by two-way anova and Tukey test (P < 0.05). α-Amylase, cystatins, mucins, and host-immune system proteins were the main proteins identified in the control group. Fibrinogen and albumin were observed only in the experimental group. Coated discs of the experimental group presented an increased SFE (P < 0.05). For both enzymes tested, the experimental group showed higher proteolytic activity (P < 0.001). Blood plasma changes the proteome of the acquired denture pellicle, increasing surface free energy and the activity of Candida albicans phospholipase and aspartyl proteinase. © 2014 Wiley Publishing Asia Pty Ltd.
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Dzib-Guerra, Wendy del C.; Escalante-Erosa, Fabiola; García-Sosa, Karlina; Derbré, Séverine; Blanchard, Patricia; Richomme, Pascal; Peña-Rodríguez, Luis M.
2016-01-01
Background: Formation and accumulation of advanced glycation end-products (AGE) is recognized as a major pathogenic process in diabetic complications, atherosclerosis and cardiovascular diseases. In addition, reactive oxygen species and free radicals have also been reported to participate in AGE formation and in cell damage. Natural products with antioxidant and antiAGE activity have great therapeutic potential in the treatment of diabetes, hypertension and related complications. Objective: to test ethanolic extracts and aqueous-traditional preparations of plants used to treat diabetes, hypertension and obesity in Yucatecan traditional medicine for their anti-AGE and free radical scavenging activities. Materials and Methods: ethanolic extracts of leaves, stems and roots of nine medicinal plants, together with their traditional preparations, were prepared and tested for their anti-AGE and antioxidant activities using the inhibition of advanced glycation end products and DPPH radical scavenging assays, respectively. Results: the root extract of C. fistula (IC50= 0.1 mg/mL) and the leaf extract of P. auritum (IC50= 0.35 mg/mL) presented significant activity against vesperlysine and pentosidine-like AGE. Although none of the aqueous traditional preparations showed significant activity in the anti-AGE assay, both the traditional preparations and the ethanolic extracts of E. tinifolia, M. zapota, O. campechianum and P. auritum showed significant activity in the DPPH reduction assay. Conclusions: the results suggest that the metabolites responsible for the detected radical-scavenging activity are different to those involved in inhibiting AGE formation; however, the extracts with antioxidant activity may contain other metabolites which are able to prevent AGE formation through a different mechanism. SUMMARY Ethanolic extracts from nine plants used to treat diabetes, hypertension and obesity in Yucatecan traditional medicine were tested for their anti-AGE and free radical
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Dzib-Guerra, Wendy Del C; Escalante-Erosa, Fabiola; García-Sosa, Karlina; Derbré, Séverine; Blanchard, Patricia; Richomme, Pascal; Peña-Rodríguez, Luis M
2016-01-01
Formation and accumulation of advanced glycation end-products (AGE) is recognized as a major pathogenic process in diabetic complications, atherosclerosis and cardiovascular diseases. In addition, reactive oxygen species and free radicals have also been reported to participate in AGE formation and in cell damage. Natural products with antioxidant and antiAGE activity have great therapeutic potential in the treatment of diabetes, hypertension and related complications. Objective: to test ethanolic extracts and aqueous-traditional preparations of plants used to treat diabetes, hypertension and obesity in Yucatecan traditional medicine for their anti-AGE and free radical scavenging activities. ethanolic extracts of leaves, stems and roots of nine medicinal plants, together with their traditional preparations, were prepared and tested for their anti-AGE and antioxidant activities using the inhibition of advanced glycation end products and DPPH radical scavenging assays, respectively. the root extract of C. fistula (IC 50 = 0.1 mg/mL) and the leaf extract of P. auritum (IC 50 = 0.35 mg/mL) presented significant activity against vesperlysine and pentosidine-like AGE. Although none of the aqueous traditional preparations showed significant activity in the anti-AGE assay, both the traditional preparations and the ethanolic extracts of E. tinifolia, M. zapota, O. campechianum and P. auritum showed significant activity in the DPPH reduction assay. the results suggest that the metabolites responsible for the detected radical-scavenging activity are different to those involved in inhibiting AGE formation; however, the extracts with antioxidant activity may contain other metabolites which are able to prevent AGE formation through a different mechanism. Ethanolic extracts from nine plants used to treat diabetes, hypertension and obesity in Yucatecan traditional medicine were tested for their anti-AGE and free radical scavenging activities.Significant activity against
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Lonsdale, Chris; Sabiston, Catherine M; Raedeke, Thomas D; Ha, Amy S C; Sum, Raymond K W
2009-01-01
Various organizations have suggested that physical education (PE) should play a central role in increasing adolescents' physical activity (PA) levels. The purpose of this study was to examine relationships between students' self-determined motivation and their PA behavior during a structured PE lesson led by their teacher and a free-choice period in which they were not required to be active. 528 Hong Kong students (mean age=15.78 years) participated in this study in April and May 2007. Situational Motivation Scale scores were used to form high and low self-determined motivation groups. Students wore a pedometer during a 20-minute structured basketball lesson and a 20-minute free choice period, during which they did not receive instruction. ANOVA revealed that self-determined motivation and PE class environments which provided students opportunities to make choices were related to greater PA. Furthermore, the difference in PA between the high and low self-determined groups was greater in the free-choice condition than the structured lesson, suggesting that self-determined motivation is especially important when students are not supervised. Findings indicated that promoting self-determined motivation may be an effective means of ensuring that PE programs are able to increase PA levels, foster self-initiated PA behaviors, and enhance adolescents' health.
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Electromyographic Activity of Scapular Muscle Control in Free-Motion Exercise
Nakamura, Yukiko; Tsuruike, Masaaki; Ellenbecker, Todd S.
2016-01-01
Context: The appropriate resistance intensity to prescribe for shoulder rehabilitative exercise is not completely known. Excessive activation of the deltoid and upper trapezius muscles could be counterproductive for scapulohumeral rhythm during humeral elevation. Objective: To identify the effects of different exercise intensities on the scapular muscles during a free-motion “robbery” exercise performed in different degrees of shoulder abduction in seated and standing positions. Design: Descriptive laboratory study. Setting: Kinesiology Adapted Physical Education Laboratory. Patients or Other Participants: A total of 15 healthy male college students (age = 20.5 ± 2.2 years, height = 174.5 ± 5.3 cm, mass = 63.8 ± 6.0 kg). Intervention(s): Participants performed 5 repetitions of a randomized exercise sequence of the robbery exercise in 2 body positions (seated, standing), 2 shoulder-abducted positions (W [20°], 90/90 [90°]) at 3 intensities (0%, 3%, and 7% body weight). Main Outcome Measure(s): Electromyographic (EMG) activity of the upper trapezius, lower trapezius, serratus anterior, anterior deltoid, and infraspinatus muscles of the upper extremity was collected. All EMG activities were normalized by the maximal voluntary isometric contraction of each corresponding muscle (%). Results: The serratus anterior, anterior deltoid, and infraspinatus EMG activities were greater at 7% body weight in the seated position compared with the standing position (P < .05). The EMG activities in all 5 muscles were greater in the 90/90 position than in the W position (P < .05). Conclusions: Scapular muscle activity modulated relative to changes in body posture and resistance intensity. These findings will enable clinicians to prescribe the appropriate level of exercise intensity and positioning during shoulder rehabilitation. PMID:26986055
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Lucconi, Giulia; Chlapanidas, Theodora; Martino, Emanuela; Gaggeri, Raffaella; Perteghella, Sara; Rossi, Daniela; Faragò, Silvio; Vigo, Daniele; Faustini, Massimo; Collina, Simona; Torre, Maria Luisa
2014-02-01
Extracts of Crataegus monogyna Jacq. (hawthorn) show an interesting free radical scavenging (FRS) effect, related to their flavonoids content. Unfortunately, their oral administration is affected by their low bioavailability. The aim of this work is to obtain a multiparticulate drug delivery system for hawthorn extracts for oral administration. The extracts from flowering tops (FL) or fruits (FR) of hawthorn were obtained with maceration, using ethanol as an extraction solvent, and their antioxidant activity was evaluated. FL extract showed the highest FRS activity (EC50 3.72 ± 1.21 µg/ml), so it was selected to prepare microparticulate systems by a spray-drying technique, which were characterized by granulometric analysis, scanning electron microscopy-energy dispersive X-ray spectroscopy, confocal fluorescence microscopy and hyperoside content. Antioxidant activity was evaluated before and after gastrointestinal transit in vitro simulation. Results indicate that the microparticulate systems maintained the antioxidant activity of hawthorn also after gastrointestinal transit in vitro simulation, exhibiting properties suitable for oral administration.
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de Manzano, Örjan; Ullén, Fredrik
2012-10-15
Free, i.e. non-externally cued generation of movement sequences is fundamental to human behavior. We have earlier hypothesized that the dorsal premotor cortex (PMD), which has been consistently implicated in cognitive aspects of planning and selection of spatial motor sequences may be particularly important for the free generation of spatial movement sequences, whereas the pre-supplementary motor area (pre-SMA), which shows increased activation during perception, learning and reproduction of temporal sequences, may contribute more to the generation of temporal structures. Here we test this hypothesis using fMRI and musical improvisation in professional pianists as a model behavior. We employed a 2 × 2 factorial design with the factors Melody (Specified/Improvised) and Rhythm (Specified/Improvised). The main effect analyses partly confirmed our hypothesis: there was a main effect of Melody in the PMD; the pre-SMA was present in the main effect of Rhythm, as predicted, as well as in the main effect of Melody. A psychophysiological interaction analysis of functional connectivity demonstrated that the correlation in activity between the pre-SMA and cerebellum was higher during rhythmic improvisation than during the other conditions. In summary, there were only subtle differences in activity level between the pre-SMA and PMD during improvisation, regardless of condition. Consequently, the free generation of rhythmic and melodic structures, appears to be largely integrated processes but the functional connectivity between premotor areas and other regions may change during free generation in response to sequence-specific spatiotemporal demands. Copyright © 2012 Elsevier Inc. All rights reserved.
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OBPR Free Flyer draft roadmap overview
NASA Technical Reports Server (NTRS)
Israelsson, Ulf
2005-01-01
OBPR Free Flyer Roadmap Purpose is to describe the OBPR research which is enabled by a free flying spacecraft capability To illustrate how research performed on free flying spacecrafts complement current and planned OBPR ISS activities.
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Tabima, D. Marcela; Specht, Patricia A.C.; Tejero, Jesús; Champion, Hunter C.; Kim-Shapiro, Daniel B.; Baust, Jeff; Mik, Egbert G.; Hildesheim, Mariana; Stasch, Johannes-Peter; Becker, Eva-Maria; Truebel, Hubert
2013-01-01
Abstract Aims: Hemoglobin-based oxygen carriers (HBOC) provide a potential alternative to red blood cell (RBC) transfusion. Their clinical application has been limited by adverse effects, in large part thought to be mediated by the intravascular scavenging of the vasodilator nitric oxide (NO) by cell-free plasma oxy-hemoglobin. Free hemoglobin may also cause endothelial dysfunction and platelet activation in hemolytic diseases and after transfusion of aged stored RBCs. The new soluble guanylate cyclase (sGC) stimulator Bay 41-8543 and sGC activator Bay 60-2770 directly modulate sGC, independent of NO bioavailability, providing a potential therapeutic mechanism to bypass hemoglobin-mediated NO inactivation. Results: Infusions of human hemoglobin solutions and the HBOC Oxyglobin into rats produced a severe hypertensive response, even at low plasma heme concentrations approaching 10 μM. These reactions were only observed for ferrous oxy-hemoglobin and not analogs that do not rapidly scavenge NO. Infusions of L-NG-Nitroarginine methyl ester (L-NAME), a competitive NO synthase inhibitor, after hemoglobin infusion did not produce additive vasoconstriction, suggesting that vasoconstriction is related to scavenging of vascular NO. Open-chest hemodynamic studies confirmed that hypertension occurred secondary to direct effects on increasing vascular resistance, with limited negative cardiac inotropic effects. Intravascular hemoglobin reduced the vasodilatory potency of sodium nitroprusside (SNP) and sildenafil, but had no effect on vasodilatation by direct NO-independent activation of sGC by BAY 41-8543 and BAY 60-2770. Innovation and Conclusion: These data suggest that both sGC stimulators and sGC activators could be used to restore cyclic guanosine monophosphate-dependent vasodilation in conditions where cell-free plasma hemoglobin is sufficient to inhibit endogenous NO signaling. Antioxid. Redox Signal. 19, 2232–2243. PMID:23697678
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Harten, Nathan; Olds, Tim; Dollman, Jim
2008-09-01
Two studies were conducted to examine the interactions between gender, play area, motor skills and free play activity in 8-11 year old school children. In both studies, boys were more active than girls. In boys, but not in girls, energy expenditure was greater for high-skill than for low-skill children (p = 0.0002), and increased as play area increased (p = 0.01). These results suggest that motor skills and play space are important variables in determining the free play activity of boys, but not of girls. This may be related to widely different play styles among boys and girls.
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Ngan, Shing-Chung; Hu, Xiaoping; Khong, Pek-Lan
2011-03-01
We propose a method for preprocessing event-related functional magnetic resonance imaging (fMRI) data that can lead to enhancement of template-free activation detection. The method is based on using a figure of merit to guide the wavelet shrinkage of a given fMRI data set. Several previous studies have demonstrated that in the root-mean-square error setting, wavelet shrinkage can improve the signal-to-noise ratio of fMRI time courses. However, preprocessing fMRI data in the root-mean-square error setting does not necessarily lead to enhancement of template-free activation detection. Motivated by this observation, in this paper, we move to the detection setting and investigate the possibility of using wavelet shrinkage to enhance template-free activation detection of fMRI data. The main ingredients of our method are (i) forward wavelet transform of the voxel time courses, (ii) shrinking the resulting wavelet coefficients as directed by an appropriate figure of merit, (iii) inverse wavelet transform of the shrunk data, and (iv) submitting these preprocessed time courses to a given activation detection algorithm. Two figures of merit are developed in the paper, and two other figures of merit adapted from the literature are described. Receiver-operating characteristic analyses with simulated fMRI data showed quantitative evidence that data preprocessing as guided by the figures of merit developed in the paper can yield improved detectability of the template-free measures. We also demonstrate the application of our methodology on an experimental fMRI data set. The proposed method is useful for enhancing template-free activation detection in event-related fMRI data. It is of significant interest to extend the present framework to produce comprehensive, adaptive and fully automated preprocessing of fMRI data optimally suited for subsequent data analysis steps. Copyright © 2010 Elsevier B.V. All rights reserved.
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NONLINEAR FORCE-FREE FIELD MODELING OF A SOLAR ACTIVE REGION USING SDO/HMI AND SOLIS/VSM DATA
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thalmann, J. K.; Wiegelmann, T.; Pietarila, A.
2012-08-15
We use SDO/HMI and SOLIS/VSM photospheric magnetic field measurements to model the force-free coronal field above a solar active region, assuming magnetic forces dominate. We take measurement uncertainties caused by, e.g., noise and the particular inversion technique, into account. After searching for the optimum modeling parameters for the particular data sets, we compare the resulting nonlinear force-free model fields. We show the degree of agreement of the coronal field reconstructions from the different data sources by comparing the relative free energy content, the vertical distribution of the magnetic pressure, and the vertically integrated current density. Though the longitudinal and transversemore » magnetic flux measured by the VSM and HMI is clearly different, we find considerable similarities in the modeled fields. This indicates the robustness of the algorithm we use to calculate the nonlinear force-free fields against differences and deficiencies of the photospheric vector maps used as an input. We also depict how much the absolute values of the total force-free, virial, and the free magnetic energy differ and how the orientation of the longitudinal and transverse components of the HMI- and VSM-based model volumes compare to each other.« less
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The First Amendment: Free Speech & a Free Press. A Curriculum Guide for High School Teachers.
ERIC Educational Resources Information Center
Eveslage, Thomas
This curriculum guide is intended to encourage students to learn how everyone benefits when young people, other citizens, and the media exercise the constitutional rights of free speech and free press. Background information on free speech issues is provided, along with classroom activities, discussion questions, and student worksheets. There are…
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Intrinsically Motivated, Free-Time Physical Activity: Considerations for Recess
ERIC Educational Resources Information Center
Stellino, Megan Babkes; Sinclair, Christina D.
2008-01-01
The current childhood obesity rates raise concern about youths' health and the role that a sedentary lifestyle plays in this growing trend. Focusing on how children choose to spend their free time is one approach that may yield ideas for reducing childhood obesity. Recess is a regularly occurring "free time" period in elementary schools. It is,…
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Biosensing of matrix metalloproteinase activity with Cd-free quantum dots
NASA Astrophysics Data System (ADS)
Plumley, John Bryan
Quantum dots (QDs) have become attractive in the biomedical field on account of their superior optical properties and stability, in comparison to traditional fluorophores. QDs also have properties which make them ideal for complex in vivo conditions. However, toxicity has been a chief concern in the eventual implementation of QDs for in vivo applications such as biosensing and tumor imaging. Commercially available QDs contain a notoriously noxious Cd component and therefore continuous research has gone into developing QDs without toxic heavy metals, generally Cd, that would still yield comparable performance in terms of their optical properties. Nonetheless, even in the case of Cd-free QDs, toxicity should be evaluated on a case by case basis, as other properties such as size, coating, stability, and charge can affect toxicity of nanomaterials as well, making it a very complex issue. With the high promise of QDs in the field of biomedical development as a motivation, this work strives to develop the efficient and repeatable synthesis of Cd-free QDs with high stability and luminescence, with proven low toxicity, and the ability to detect active matrix metalloproteinase (MMP) in a biosensing system, designed to identify direct biomarkers for pathological conditions, which in turn would enable early disease diagnosis and better treatment development. In this work, highly luminescent ZnSe:Mn/ZnS QDs have been synthesized, characterized, and modified with peptides with a bioconjugation procedure that utilized thiol-metal affinity. Experiments aiming at MMP detection were conducted using the peptide/QD conjugates. In addition, the ApoTox-Glo(TM) Triplex assay was utilized to evaluate cytotoxicity, and a safe concentration below 0.125 microM was identified for peptide-coated ZnSe:Mn/ZnS QDs in water. Finally, in contribution to developing an in vivo fiberoptic system for sensing MMP activity, the QDs were successfully tethered to silica and MMP detection was demonstrated
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2018-01-01
The ability of frustrated Lewis pairs (FLPs) to activate H2 is of significant interest for metal-free catalysis. The activation of H2 is also the key element of parahydrogen-induced polarization (PHIP), one of the nuclear spin hyperpolarization techniques. It is demonstrated that o-phenylene-based ansa-aminoboranes (AABs) can produce 1H nuclear spin hyperpolarization through a reversible interaction with parahydrogen at ambient temperatures. Heteronuclei are useful in NMR and MRI as well because they have a broad chemical shift range and long relaxation times and may act as background-free labels. We report spontaneous formation of 15N hyperpolarization of the N–H site for a family of AABs. The process is efficient at the high magnetic field of an NMR magnet (7 T), and it provides up to 350-fold 15N signal enhancements. Different hyperpolarization effects are observed with various AAB structures and in a broad temperature range. Spontaneous hyperpolarization, albeit an order of magnitude weaker than that for 15N, was also observed for 11B nuclei. PMID:29401399
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Statistical study of free magnetic energy and flare productivity of solar active regions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Su, J. T.; Jing, J.; Wang, S.
Photospheric vector magnetograms from the Helioseismic and Magnetic Imager on board the Solar Dynamic Observatory are utilized as the boundary conditions to extrapolate both nonlinear force-free and potential magnetic fields in solar corona. Based on the extrapolations, we are able to determine the free magnetic energy (FME) stored in active regions (ARs). Over 3000 vector magnetograms in 61 ARs were analyzed. We compare FME with the ARs' flare index (FI) and find that there is a weak correlation (<60%) between FME and FI. FME shows slightly improved flare predictability relative to the total unsigned magnetic flux of ARs in themore » following two aspects: (1) the flare productivity predicted by FME is higher than that predicted by magnetic flux and (2) the correlation between FI and FME is higher than that between FI and magnetic flux. However, this improvement is not significant enough to make a substantial difference in time-accumulated FI, rather than individual flare, predictions.« less
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Yang, Xi-Juan; Dang, Bin; Fan, Ming-Tao
2018-04-11
In this study, the polyphenols composition and antioxidant properties of 12 blue highland barley varieties planted on the Qinghai-Tibet Plateau area were measured. The contents of the free, bound and total phenolic acids varied between 166.20-237.60, 170.10-240.75 and 336.29-453.94 mg of gallic acid equivalents per 100 g of dry weight (DW) blue highland barley grains, while the free and bound phenolic acids accounted for 50.09% and 49.91% of the total phenolic acids, respectively. The contents of the free, bound and total flavones varied among 20.61-25.59, 14.91-22.38 and 37.91-47.98 mg of catechin equivalents per 100 g of dry weight (DW) of blue highland barley grains, while the free and bound flavones accounted for 55.90% and 44.10% of the total flavones, respectively. The prominent phenolic compounds in the blue hulless barley grains were gallic acid, benzoic acid, syringic acid, 4-coumaric acid, naringenin, hesperidin, rutin, (+)-catechin and quercetin. Among these, protocatechuic acid, chlorogenic acid and (+)-catechin were the major phenolic compounds in the free phenolics extract. The most abundant bound phenolics were gallic acid, benzoic acid, syringic acid, 4-coumaric acid, benzoic acid, dimethoxybenzoic acid, naringenin, hesperidin, quercetin and rutin. The average contribution of the bound phenolic extract to the DPPH • free radical scavenging capacity was higher than 86%, that of free phenolic extract to the ABTS •+ free radical scavenging capacity was higher than 79%, and that of free phenolic (53%) to the FRAP antioxidant activity was equivalent to that of the bound phenol extract (47%). In addition, the planting environment exerts a very important influence on the polyphenol composition, content and antioxidant activity of blue highland barley. The correlation analysis showed that 2,4-hydroxybenzoic acid and protocatechuic acid were the main contributors to the DPPH • and ABTS •+ free radical scavenging capacity in the free phenolic extract
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[Smoke-free environment--nurse attitudes towards smoke-free regulations].
Kaleta, Dorota; Polańska, Kinga; Dziankowska-Zaborszczyk, Elzbieta; Bak-Romaniszyn, Leokadia; Czarnecka, Karolina; Drygas, Wojciech
2009-01-01
The aim of the study was to analyze the nurse attitudes towards smoke-free regulations in public places. The study population consisted of 299 nurses. Among the study population questionnaire was conducted including socio-demographic characteristic, smoking and ETS profile, knowledge about health effects of smoking and abilities for conduction of antismoking counseling. Detail information was collected about nurse opinion on smoke-free public places such as offices, other workplaces, health and educational buildings, restaurants and bars. About 18% of study participants declared current tobacco smoking and 25% were former smokers. Almost all participating in the study women (85%-98%) are in favor of smoking ban in offices, health and educational buildings. 75% supported smoking ban in workplaces but 15% of them were somewhat opposed. Most of the nurses were in favor of smoke-free restaurants (64%) but they were less likely to support smoke-free bars, pubs and clubs (45%). Unfortunately 63% of interview women do not accept smoking ban in private cars. The percentage of women who support total ban of smoking in the presence of pregnant women was 93% and in the presence of children 79%. It is important to conduct educational and informational activities to increase public awareness on health consequences of active and passive smoking and the ways of elimination of such exposures.
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Zhang, Zhongshan; Wang, Xiaomei; Li, Jingfen; Wang, Guozhi; Mao, Genxiang
2016-03-01
In this study, the optimization of the extraction conditions of polysaccharide from 'Anji Baicha' (Camellia sinensis (L.) O. Kuntze) (AP) was investigated by response surface methodology (RSM). Three main independent variables (extraction temperature, time, ratio of water to raw material) were taken into consideration. And then the free radical scavenging activities of the sample were investigated including scavenging effects of superoxide and hydroxyl radicals. The RSM analysis showed good correspondence between experimental and predicted values.. The optimal condition to obtain the highest yield of AP was determined as follows: temperature 76.79 °C, time 2.48 h, ratio of water to material 22.53 mL/g. For the free radical scavenging activity, the IC50 values of Vc and AP were 7.78 and 83.25 μg/mL. And for the scavenging effect on hydroxyl radical, that of AP and Vc were 1.80 and 1.69 mg/mL. AP showed excellent antioxidant activity. This exhibited AP had a good potential for antioxidant. The purification and structure needs to be study in further. Copyright © 2015 Elsevier B.V. All rights reserved.
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Lee, Waisin; Xu, Mingjing; Li, Yue; Gu, Yong; Chen, Jianping; Wong, Derek; Fung, Peter C W; Shen, Jiangang
2011-10-01
Although the relationship between hypercholesterolemia and oxidative stress has been extensively investigated, direct evidence regarding to the roles of cholesterol accumulation in the generations of reactive oxygen species (ROS) and apoptotic cell death under oxidative stress is lack. In this study, we investigated productions of superoxide anions (O(2)(-)) and nitric oxide (NO), and apoptotic cell death in wild type Chinese hamster ovary (CHO) cells and cholesterol accumulated CHO cells genetically and chemically. Oxidative stress was induced by menadione challenge. The results revealed that abundance of free cholesterol (FC) promoted menadione-induced O(2)(-) and NO productions. FC accumulation down-regulated eNOS expression but up-regulated NADPH oxidases, and inhibited the activities of superoxide dismutase (SOD) and catalase. Treatment of menadione increased the expressions of iNOS and qp91 phox, enhanced the activities of SOD and catalase in the wild-type CHO cells but inhibited the activity of glutathione peroxidase in the cholesterol accumulated CHO cells. Moreover, FC abundance promoted apoptotic cell death in these cells. Taken together, those results suggest that free cholesterol accumulation aggravates menadione-induced oxidative stress and exacerbates apoptotic cell death. Copyright © 2011 Elsevier Inc. All rights reserved.
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Samrakandi, M M; Roques, C; Michel, G
1994-05-01
In order to assess the sporocidal activity of chlorine and peracetic acid (PAA), alone and in combination, against a spored biofilm, the biofilms of two species (Bacillus subtilis ATCC 6633 and Bacillus megaterium ATCC 8245) were formed on inert support (tygon). A sporulation kinetic of these bacteria in biofilm was established. Sporocidal properties of chlorine and PAA were compared against free spores, spores fixed by drying and spores in biofilm. The combination of these two products was also tested. Minimal sporocidal concentrations (MSC) of the two products towards free spores were determined (contact time 5 mn). The efficacy of these MSC were evaluated in terms of contact time on adhered spores and on spores in biofilm. Chlorine and PAA exhibited an excellent sporocidal activity. The combination of PAA and chlorine, tested by checkerboard micromethod, was found to be synergistic in case of free or adhered spores. The spored biofilm showed a high resistance. The combination of these two products revealed then only an additive effect.
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Comparison of pedometer and accelerometer measures of free-living physical activity.
Tudor-Locke, Catrine; Ainsworth, Barbara E; Thompson, Raymond W; Matthews, Charles E
2002-12-01
The purpose of this investigation was 1) to evaluate agreement between dual-mode CSA accelerometer outputs and Yamax pedometer outputs assessed concurrently under free-living conditions; 2) to determine the relationship between pedometer-steps per day and CSA-time spent in inactivity and in light-, moderate-, and vigorous-intensity activities; and 3) to identify a value of pedometer-steps per day that corresponds with a minimum of 30 CSA-min x d(-1) of moderate ambulatory activity. Data were analyzed from 52 participants (27 men, 25 women; mean age = 38.2 +/- 12.0 yr; mean BMI = 26.4 +/- 4.5 kg x m(-2)) who were enrolled in the International Physical Activity Questionnaire study and wore both motion sensors during waking hours for 7 consecutive days. Participants averaged 415.0+/-159.5 CSA-counts x min(-1) x d(-1), 357,601 +/- 138,425 CSA-counts x d(-1), 11,483 +/- 3,856 CSA-steps x d(-1), and 9,638 +/- 4,030 pedometer-steps x d(-1). There was a strong relationship between all CSA outputs and pedometer outputs (r = 0.74-0.86). The mean difference in steps detected between instruments was 1845+/-2116 steps x d(-1) (CSA > pedometer; t = 6.29, P < 0.0001). There were distinct differences (effect sizes >0.80) in mean CSA-time (min x d(-1)) in moderate and vigorous activity with increasing pedometer-determined activity quartiles; no differences were noted for inactivity or light activity. Approximately 33 CSA-min x d(-1) of moderate activity corresponded with 8000 pedometer-steps x d(-1). Differences in mean steps per day detected may be due to differences in set instrument sensitivity thresholds and/or attachment. Additional studies with different populations are needed to confirm a recommended number of steps per day associated with the duration and intensity of public health recommendations for ambulatory activity.
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[Molecules involved in sperm-zona pellucida interaction in mammals. Role in human fertility].
Serres, Catherine; Auer, Jana; Petit, François; Patrat, Catherine; Jouannet, Pierre
2008-01-01
Fertilization in mammals requires an initial interaction of sperm with the oocyte envelope, the zona pellucida (ZP), before it reaches the oocyte. ZP is a highly glycosylated structure, composed of three (mouse) or four (rabbit, boar, bovine, humans...) glycoproteins. The presence of ZP around the oocyte does not allow heterospecific fertilization. This barrier is principally due to the presence of species-specific glycosylations on ZP proteins. Sperm bind ZP by means of membrane receptors which recognize carbohydrate moieties on ZP glycoproteins according to a well-precised sequential process. Upon initial attachment, spermatozoa bind ZP3/ZP4 which induces the sperm acrosome exocytosis followed by a secondary binding of acrosome reacted spermatozoa to ZP2 and by ZP penetration. The sperm receptors are adhesive proteins or integral plasma membrane proteins linked to intraspermatic signalling pathways activating the acrosome reaction. Over the last twenty years, numerous studies have been carried out to identify sperm receptors to ZP in several species, but the data in humans are still incomplete. Work initiated in our research group has identified several proteins interacting with recombinant human ZP2, ZP3 and ZP4, among which are glycolytic enzymes. These enzymes are involved in the gamete interaction by means of their affinity to sugars and not by their catalytic properties. From a clinical point of view, an observed lack or weak expression of some sperm receptors to ZP3 in cases of idiopathic infertility associated with in vitro fertilization failure suggests that knowing the molecular mechanism driving the gamete recognition can be important at the diagnostic level. Furthermore, it has been shown that proteins that mediate gamete recognition diverge rapidly, as a result of positive darwinian selection. A sexual conflict can drive co-evolution of reproductive molecules in both sexes resulting in reproductive isolation and species emergence.
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Chu, Ke; Wang, Fan; Zhao, Xiao-Lin; Wang, Xin-Wei; Tian, Ye
2017-12-01
Heteroatom doping is an effective strategy to enhance the catalytic activity of graphene and its hybrid materials. Despite a growing interest of P-doped graphene (P-G) in energy storage/generation applications, P-G has rarely been investigated for electrochemical sensing. Herein, we reported the employment of P-G as both metal-free catalyst and metal catalyst support for electrochemical detection of dopamine (DA). As a metal-free catalyst, P-G exhibited prominent DA sensing performances due to the important role of P doping in improving the electrocatalytic activity of graphene toward DA oxidation. Furthermore, P-G could be an efficient supporting material for loading Au nanoparticles, and resulting Au/P-G hybrid showed a dramatically enhanced electrocatalytic activity and extraordinary sensing performances with a wide linear range of 0.1-180μM and a low detection limit of 0.002μM. All these results demonstrated that P-G might be a very promising electrode material for electrochemical sensor applications. Copyright © 2017 Elsevier B.V. All rights reserved.
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Theoretical insights on the antioxidant activity of edaravone free radical scavengers derivatives
NASA Astrophysics Data System (ADS)
Cerón-Carrasco, José P.; Roy, Hélène M.; Cerezo, Javier; Jacquemin, Denis; Laurent, Adèle D.
2014-04-01
The prediction of antioxidant properties is not straightforward due to the complexity of the in vivo systems. Here, we use theoretical descriptors, including the potential of ionization, the electrodonating power and the spin density distribution, to characterize the antioxidant capacity of edaravone (EDV) derivatives. Our computations reveal the relationship between these parameters and their potential bioactivity as free radical scavengers. We conclude that more efficient antioxidants could be synthesized by tuning the R1 and R2 positions of the EDV structure, rather than modifying the R3 group. Such modifications might improve the antioxidant activity in neutral and deprotonated forms.
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Hekler, Eric B; Buman, Matthew P; Grieco, Lauren; Rosenberger, Mary; Winter, Sandra J; Haskell, William; King, Abby C
2015-04-15
There is increasing interest in using smartphones as stand-alone physical activity monitors via their built-in accelerometers, but there is presently limited data on the validity of this approach. The purpose of this work was to determine the validity and reliability of 3 Android smartphones for measuring physical activity among midlife and older adults. A laboratory (study 1) and a free-living (study 2) protocol were conducted. In study 1, individuals engaged in prescribed activities including sedentary (eg, sitting), light (sweeping), moderate (eg, walking 3 mph on a treadmill), and vigorous (eg, jogging 5 mph on a treadmill) activity over a 2-hour period wearing both an ActiGraph and 3 Android smartphones (ie, HTC MyTouch, Google Nexus One, and Motorola Cliq). In the free-living study, individuals engaged in usual daily activities over 7 days while wearing an Android smartphone (Google Nexus One) and an ActiGraph. Study 1 included 15 participants (age: mean 55.5, SD 6.6 years; women: 56%, 8/15). Correlations between the ActiGraph and the 3 phones were strong to very strong (ρ=.77-.82). Further, after excluding bicycling and standing, cut-point derived classifications of activities yielded a high percentage of activities classified correctly according to intensity level (eg, 78%-91% by phone) that were similar to the ActiGraph's percent correctly classified (ie, 91%). Study 2 included 23 participants (age: mean 57.0, SD 6.4 years; women: 74%, 17/23). Within the free-living context, results suggested a moderate correlation (ie, ρ=.59, P<.001) between the raw ActiGraph counts/minute and the phone's raw counts/minute and a strong correlation on minutes of moderate-to-vigorous physical activity (MVPA; ie, ρ=.67, P<.001). Results from Bland-Altman plots suggested close mean absolute estimates of sedentary (mean difference=-26 min/day of sedentary behavior) and MVPA (mean difference=-1.3 min/day of MVPA) although there was large variation. Overall, results suggest
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Kim, Gwang-Won; Kim, Seok-Kwun; Jeong, Gwang-Woo
2016-03-01
The purpose of this study was to evaluate the brain activation pattern associated with sexual orientation and its correlation with the level of the free testosterone (free T) in postoperative female-to-male (FtM) transsexuals using a 3.0-Tesla functional magnetic resonance imaging (fMRI). Eleven postoperative FtM transsexuals with sex reassignment surgery underwent fMRI on a 3.0-T MR scanner. Brain activity was measured while viewing erotic male and female nude pictures. The average level of free T in the FtM transsexuals was in the normal range of heterosexual men. The brain areas with predominant activities during viewing female nude pictures in contrast to male pictures included the hippocampus, parahippocampal gyrus, anterior cingulate gyrus, putamen, amygdala, hypothalamus, and insula (p < 0.005). The free T levels were positively correlated with the BOLD signal changes in the parahippocampal gyrus (Spearman's rho = 0.91, p < 0.001), hippocampus (rho = 0.90, p < 0.001), insula (rho = 0.68, p < 0.05), putamen (rho = 0.66, p < 0.05), and amygdala (rho = 0.64, p < 0.05). Compared to FtM transsexuals with deficient level of free T, the FtM transsexuals with normal range of free T showed significantly higher activities in the parahippocampal gyrus, hippocampus, insula, putamen, and amygdala during viewing female nude pictures (p < 0.005). This study revealed the specific brain activation pattern associated with sexual orientation and its correlation with free T in the postoperative FtM transsexuals. These findings are applicable in understanding the neural mechanism on sexual arousal in FtM transsexuals and their sexual orientation in connection with the free T levels.
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Kusar, A; Zupancic, A; Sentjurc, M; Baricevic, D
2006-10-01
Yellow gentian (Gentiana lutea L.) is a herbal species with a long-term use in traditional medicine due to its digestive and stomachic properties. This paper presents an investigation of the free radical scavenging activity of methanolic extracts of yellow gentian leaves and roots in two different systems using electron spin resonance (ESR) spectrometry. Assays were based on the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) and the superoxide radicals (O2*-) generated by the xanthine/xanthine oxidase (X/XO) system. The results of gentian methanolic extracts were compared with the antioxidant capacity of synthetic antioxidant butylated hydroxyanisole (BHA). This study proves that yellow gentian leaves and roots exhibit considerable antioxidant properties, expressed either by their capability to scavenge DPPH or superoxide radicals.
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Loprinzi, Paul D; Frith, Emily
2017-04-01
Albeit limited, some emerging work, using convenience-based samples, has demonstrated that greater motor skill development is associated with higher physical activity among preschool-aged children. The purpose of this study was to evaluate this topic using data from the 2012 National Youth Fitness Survey that included 329 preschool-aged children (3-5 years). Parents proxy-reported their child's physical activity, with motor skill level assessed from the Test of Gross Motor Development-Second Edition (TGMD2). Motor skill levels (Gross Motor Quotient, locomotor or object control) were not associated with preschool free-living physical activity in any analytic model. Thus, in this large sample of preschoolers, contrary to research with older children, motor skill level was not associated with physical activity. Findings are discussed in terms of study limitations of (a) a reliance on parent report of children's physical activity levels and (b) the possibility that physical activity data within the national survey were too limited in range to show possible associations to motor skill development with higher levels of free-living physical activity in preschoolers.
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Dominick, Gregory M; Winfree, Kyle N; Pohlig, Ryan T; Papas, Mia A
2016-09-19
Wearable activity monitors such as Fitbit enable users to track various attributes of their physical activity (PA) over time and have the potential to be used in research to promote and measure PA behavior. However, the measurement accuracy of Fitbit in absolute free-living conditions is largely unknown. To examine the measurement congruence between Fitbit Flex and ActiGraph GT3X for quantifying steps, metabolic equivalent tasks (METs), and proportion of time in sedentary activity and light-, moderate-, and vigorous-intensity PA in healthy adults in free-living conditions. A convenience sample of 19 participants (4 men and 15 women), aged 18-37 years, concurrently wore the Fitbit Flex (wrist) and ActiGraph GT3X (waist) for 1- or 2-week observation periods (n=3 and n=16, respectively) that included self-reported bouts of daily exercise. Data were examined for daily activity, averaged over 14 days and for minutes of reported exercise. Average day-level data included steps, METs, and proportion of time in different intensity levels. Minute-level data included steps, METs, and mean intensity score (0 = sedentary, 3 = vigorous) for overall reported exercise bouts (N=120) and by exercise type (walking, n=16; run or sports, n=44; cardio machine, n=20). Measures of steps were similar between devices for average day- and minute-level observations (all P values > .05). Fitbit significantly overestimated METs for average daily activity, for overall minutes of reported exercise bouts, and for walking and run or sports exercises (mean difference 0.70, 1.80, 3.16, and 2.00 METs, respectively; all P values < .001). For average daily activity, Fitbit significantly underestimated the proportion of time in sedentary and light intensity by 20% and 34%, respectively, and overestimated time by 3% in both moderate and vigorous intensity (all P values < .001). Mean intensity scores were not different for overall minutes of exercise or for run or sports and cardio-machine exercises (all P
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Herrera-Ballesteros, Victor H; Castro, Franz; Gómez, Beatriz
2018-04-27
Caracterizar el gasto de bolsillo privado en medicamentos en función de los determinantes sociodemográficos y socioeconómicos. MATERIALES Y MéTODOS: La fuente de datos es la Encuesta de Gasto de Bolsillo en Medicamentos de 2014. Se caracterizó el gasto de bolsillo privado mediante variables explicativas sociodemográficas (SOD) y socioeconómicas (SES). Se hizo análisis factorial por componentes principales, regresión logística y lineal simple. Los Odds Ratio demuestran que la educación y la zona geográfica son determinantes fundamentales que inciden en el gasto de bolsillo. Los medicamentos son productos necesarios, en adición a que el gasto de bolsillo aumenta a un promedio del 2% por cada año de vida cronológica adicional. Existe mayor vulnerabilidad en las zonas más pauperizadas respecto del acceso a medicamentos, en especial en las indígenas e implica un mayor riesgo de gasto catastrófico a menor ingreso ante la mayor prevalencia de enfermedades crónicas. Copyright © 2018. Published by Elsevier Inc.
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Vasanthakumar, Aparna; Davis, Justin W; Abunimeh, Manal; Söderholm, Jonas; Zha, Jiuhong; Dumas, Emily O; Cohen, Daniel E; Waring, Jeffrey F; Lagging, Martin
2018-01-01
Genetic variants of inosine triphosphatase (ITPA) that confer reduced ITPase activity are associated with protection against ribavirin(RBV)-induced hemolytic anemia in peginterferon(IFN)/RBV-based treatment of hepatitis C virus (HCV). Patients with reduced ITPase activity showed improved treatment efficacy when treated with IFN/RBV. In addition, a genetic polymorphism near the IL28B gene is associated with an improved response to IFN/RBV treatment. RBV has been an important component of IFN-containing regimens, and is currently recommended in combination with several IFN-free regimens for treatment of harder to cure HCV infections. To evaluate whether genetic variations that reduce ITPase activity impact RBV-induced anemia in IFN-free/RBV regimens. In this study, genetic analyses were conducted in the PEARL-IV trial to investigate the effect of activity-reducing ITPA variants as well as IL28B polymorphism on anemia, platelet (PLT) counts, and virologic response in HCV genotype1a-infected patients treated with the direct-acting antiviral (DAA) regimen of ombitasvir/paritaprevir/ritonavir and dasabuvir±RBV. Reduction in ITPase activity and homozygosity for the IL28Brs12979860 CC genotype protected against RBV-induced anemia. In patients receiving RBV, reduced ITPase activity was associated with reduced plasma RBV concentration and higher PLT counts. ITPase activity had no impact on response to DAA treatment, viral kinetics, or baseline IP-10 levels. Our study demonstrates that genetics of ITPA and IL28B may help identify patients protected from RBV-induced anemia when treated with IFN-free regimens. Our work demonstrates for the first time that IL28B genetics may also have an impact on RBV-induced anemia. This may be of particular significance in patients with difficult-to-cure HCV infections, such as patients with decompensated cirrhosis where RBV-containing regimens likely will continue to be recommended.
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Solecka, Jolanta; Guśpiel, Adam; Postek, Magdalena; Ziemska, Joanna; Kawęcki, Robert; Lęczycka, Katarzyna; Osior, Agnieszka; Pietrzak, Bartłomiej; Pypowski, Krzysztof; Wyrzykowska, Agata
2014-09-30
A series of 3,4-dihydroisoquinoline-3-carboxylic acid derivatives were synthesised and tested for their free-radical scavenging activity using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH·), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical (ABTS·+), superoxide anion radical (O2·-) and nitric oxide radical (·NO) assays. We also studied d-amino acid oxidase (DAAO), acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activity. Almost each of newly synthesised compounds exhibited radical scavenging capabilities. Moreover, several compounds showed moderate inhibitory activities against DAAO, AChE and BuChE. Compounds with significant free-radical scavenging activity may be potential candidates for therapeutics used in oxidative-stress-related diseases.
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Active disturbance rejection controller of fine tracking system for free space optical communication
NASA Astrophysics Data System (ADS)
Cui, Ning; Liu, Yang; Chen, Xinglin; Wang, Yan
2013-08-01
Free space optical communication is one of the best approaches in future communications. Laser beam's acquisition, pointing and tracking are crucial technologies of free space optical communication. Fine tracking system is important component of APT (acquisition, pointing and tracking) system. It cooperates with the coarse pointing system in executing the APT mission. Satellite platform vibration and disturbance, which reduce received optical power, increase bit error rate and affect seriously the natural performance of laser communication. For the characteristic of satellite platform, an active disturbance rejection controller was designed to reduce the vibration and disturbance. There are three major contributions in the paper. Firstly, the effects of vibration on the inter satellite optical communications were analyzed, and the reasons and characters of vibration of the satellite platform were summarized. The amplitude-frequency response of a filter was designed according to the power spectral density of platform vibration of SILEX (Semiconductor Inter-satellite Laser Experiment), and then the signals of platform vibration were generated by filtering white Gaussian noise using the filter. Secondly, the fast steering mirror is a key component of the fine tracking system for optical communication. The mechanical design and model analysis was made to the tip/tilt mirror driven by the piezoelectric actuator and transmitted by the flexure hinge. The transfer function of the fast steering mirror, camera, D/A data acquisition card was established, and the theory model of transfer function of this system was further obtained. Finally, an active disturbance rejection control method is developed, multiple parallel extended state observers were designed for estimation of unknown dynamics and external disturbance, and the estimated states were used for nonlinear feedback control and compensation to improve system performance. The simulation results show that the designed
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Collier, A; Jackson, M; Dawkes, R M; Bell, D; Clarke, B F
1988-11-01
Free radicals are unstable chemical species which react with and oxidize adjacent molecules, particularly polyunsaturated lipids. The diene-conjugated non-peroxide isomer of linoleic acid (PL-9,11-LA') has been identified as the main diene-conjugated compound in plasma, and is a probable marker of free radical activity. The aim of the current study was to determine whether the level of PL-9,11-LA', measured by HPLC, is altered in insulin-dependent diabetes, and to investigate whether any abnormality demonstrated correlated with microvascular disease in the form of retinopathy. There was no difference in the concentrations of linoleic acid between the diabetic and control groups (422(129) vs 402(81) (SD) mumol l-1). However, the concentration of PL-9,11-LA' was significantly reduced in the diabetic group compared with control group (15.6(6.7) vs 19.3(3.9) mumol l-1, p less than 0.01), with the molar ratio of PL-9,11-LA':linoleic acid x 100 similarly reduced (3.8(1.3) vs 5.0(1.6)%, p less than 0.005). This study does not support the concept that free radicals play a significant role in the development of diabetic vascular disease.
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Free-Free Absorption on Parsec Scales in Seyfert Galaxies
NASA Astrophysics Data System (ADS)
Roy, A. L.; Ulvestad, J. S.; Wilson, A. S.; Colbert, E. J. M.; Mundell, C. G.; Wrobel, J. M.; Norris, R. P.; Falcke, H.; Krichbaum, T.
Seyfert galaxies come in two main types (types 1 and 2) and the difference is probably due to obscuration of the nucleus by a torus of dense molecular material. The inner edge of the torus is expected to be ionized by optical and ultraviolet emission from the active nucleus, and will radiate direct thermal emission (e.g. NGC 1068) and will cause free-free absorption of nuclear radio components viewed through the torus (e.g. Mrk 231, Mrk 348, NGC 2639). However, the nuclear radio sources in Seyfert galaxies are weak compared to radio galaxies and quasars, demanding high sensitivity to study these effects. We have been making sensitive phase referenced VLBI observations at wavelengths between 21 and 2 cm where the free-free turnover is expected, looking for parsec-scale absorption and emission. We find that free-free absorption is common (e.g. in Mrk 348, Mrk 231, NGC 2639, NGC 1068) although compact jets are still visible, and the inferred density of the absorber agrees with the absorption columns inferred from X-ray spectra (Mrk 231, Mrk 348, NGC 2639). We find one-sided parsec-scale jets in Mrk 348 and Mrk 231, and we measure low jet speeds (typically £ 0.1 c). The one-sidedness probably is not due to Doppler boosting, but rather is probably free-free absorption. Plasma density required to produce the absorption is Ne 3 2 105 cm-3 assuming a path length of 0.1 pc, typical of that expected at the inner edge of the obscuring torus.
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Su, Buli; Zhang, Zhe; Wu, Mianbin; Lin, Jianping; Yang, Lirong
2016-05-26
High costs and low production efficiency are a serious constraint to bio-based xylitol production. For industrial-scale production of xylitol, a plasmid-free Escherichia coli for arabitol-free xylitol production from corncob hemicellulosic hydrolysate has been constructed. Instead of being plasmid and inducer dependent, this strain relied on multiple-copy integration of xylose reductase (XR) genes into the chromosome, where their expression was controlled by the constitutive promoter P43. In addition, to minimize the flux from L-arabinose to arabitol, two strategies including low XR total activity and high selectivity of XR has been adopted. Arabitol was significantly decreased using plasmid-free strain which had lower XR total activity and an eight point-mutations of XR with a 27-fold lower enzyme activity toward L-arabinose was achieved. The plasmid-free strain in conjunction with this mutant XR can completely eliminate arabitol formation in xylitol production. In fed-batch fermentation, this plasmid-free strain produced 143.8 g L(-1) xylitol at 1.84 g L(-1) h(-1) from corncob hemicellulosic hydrolysate. From these results, we conclude that this route by plasmid-free E. coli has potential to become a commercially viable process for xylitol production.
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Su, Buli; Zhang, Zhe; Wu, Mianbin; Lin, Jianping; Yang, Lirong
2016-01-01
High costs and low production efficiency are a serious constraint to bio-based xylitol production. For industrial-scale production of xylitol, a plasmid-free Escherichia coli for arabitol-free xylitol production from corncob hemicellulosic hydrolysate has been constructed. Instead of being plasmid and inducer dependent, this strain relied on multiple-copy integration of xylose reductase (XR) genes into the chromosome, where their expression was controlled by the constitutive promoter P43. In addition, to minimize the flux from L-arabinose to arabitol, two strategies including low XR total activity and high selectivity of XR has been adopted. Arabitol was significantly decreased using plasmid-free strain which had lower XR total activity and an eight point-mutations of XR with a 27-fold lower enzyme activity toward L-arabinose was achieved. The plasmid-free strain in conjunction with this mutant XR can completely eliminate arabitol formation in xylitol production. In fed-batch fermentation, this plasmid-free strain produced 143.8 g L−1 xylitol at 1.84 g L−1 h−1 from corncob hemicellulosic hydrolysate. From these results, we conclude that this route by plasmid-free E. coli has potential to become a commercially viable process for xylitol production. PMID:27225023
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USDA-ARS?s Scientific Manuscript database
The objective of this study was to evaluate chemical compositions, free amino acid contents, and antioxidant activities of different cuts of Hanwoo (Bos taurus coreanae) beef. Beef preferences and prices in the Korean market depend on cut. Therefore, comparisons were made between high-preference (gr...
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Overview of OBPR Free Flyer System Concept
NASA Technical Reports Server (NTRS)
Leung, Ronald Y.; Lieberman, Alvin S.
2003-01-01
Contents include the following:OBPR free flyer theme. OBPR free flyer technical activity last 2 years. GSFC integrated mission design center (IMDC) studies. Free flyer assumptions and goals. Free flyer total payload reference concept capabilities. FFM reference payload requirements. FFM mission. FFM medium summary. FFH block diagram FFH spacecraft configuration.concept.
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Kemmochi, Yukio; Tsutsumi, Kaori; Arikawa, Akihiro; Nakazawa, Hiroyuki
2002-11-22
2,3,7,8-Substituted polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDD/Fs) and non-ortho-substituted polychlorinated biphenyls (PCBs) account for almost all of the total toxic equivalents (TEQ) in environmental samples. Activated carbon columns are used to fractionate the samples for GC-MS analysis or bioassay. Micropore-free surface-activated carbon is highly selective for PCDD/Fs and non-ortho-PCBs and can improve the conventional activated carbon column clean-up. Along with sulfuric acid-coated diatomaceous earth columns, micropore-free surface-activated carbon provides a rapid, robust, and high-throughput sample preparation method for PCDD/Fs and non-ortho-PCBs analysis.
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Guidoux, Romain; Duclos, Martine; Fleury, Gérard; Lacomme, Philippe; Lamaudière, Nicolas; Saboul, Damien; Ren, Libo; Rousset, Sylvie
2017-05-01
The proliferation of smartphones is creating new opportunities to monitor and interact with human subjects in free-living conditions since smartphones are familiar to large segments of the population and facilitate data collection, transmission and analysis. From accelerometry data collected by smartphones, the present work aims to estimate time spent in different activity categories and the energy expenditure in free-living conditions. Our research encompasses the definition of an energy-saving function (Pred EE ) considering four physical categories of activities (still, light, moderate and vigorous), their duration and metabolic cost (MET). To create an efficient discrimination function, the method consists of classifying accelerometry-transformed signals into categories and of associating each category with corresponding Metabolic Equivalent Tasks. The performance of the Pred EE function was compared with two previously published functions (f(η,d)aedes,f(η,d)nrjsi), and with two dedicated sensors (Armband® and Actiheart®) in free-living conditions over a 12-h monitoring period using 30 volunteers. Compared to the two previous functions, Pred EE was the only one able to provide estimations of time spent in each activity category. In relative value, all the activity categories were evaluated similarly to those given by Armband®. Compared to Actiheart®, the function underestimated still activities by 10.1% and overestimated light- and moderate-intensity activities by 7.9% and 4.2%, respectively. The total energy expenditure error produced by Pred EE compared to Armband® was lower than those given by the two previous functions (5.7% vs. 14.1% and 17.0%). Pred EE provides the user with an accurate physical activity feedback which should help self-monitoring in free-living conditions. Copyright © 2017 Elsevier Inc. All rights reserved.
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Louros, Nikolaos N; Chrysina, Evangelia D; Baltatzis, Georgios E; Patsouris, Efstratios S; Hamodrakas, Stavros J; Iconomidou, Vassiliki A
2016-03-01
Human zona pellucida (ZP) is composed of four glycoproteins, namely ZP1, ZP2, ZP3 and ZP4. ZP proteins form heterodimers, which are incorporated into filaments through a common bipartite polymerizing component, designated as the ZP domain. The latter is composed of two individually folded subdomains, named ZP-N and ZP-C. Here, we have synthesized six 'aggregation-prone' peptides, corresponding to a common interface of human ZP2, ZP3 and ZP4. Experimental results utilizing electron microscopy, X-ray diffraction, ATR FT-IR spectroscopy and polarizing microscopy indicate that these peptides self-assemble forming fibrils with distinct amyloid-like features. Finally, by performing detailed modeling and docking, we attempt to shed some light in the self-assembly mechanism of human ZP proteins. © 2016 Federation of European Biochemical Societies.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Kurachi, H.; Wakimoto, H.; Sakumoto, T.
1984-02-01
The specific radioimmunoassay system was developed for the titration of the antibodies to porcine zona pellucida (ZP) in human sera by using /sup 125/I-labeled purified porcine ZP as antigen, which is known to have cross-reactivity with human ZP. The antibodies in human sera were detected in 3 of 11 (27%) women with unexplained infertility, in 16 of 48 (33%) amenorrheic patients, in 4 of 12 (33%) fertile women, and in 3 of 10 (30%) men. Moreover, antibody titers in infertile women were no higher than those in fertile women and in men. These results seem to suggest that the antibodiesmore » in human sera that cross-react with porcine ZP may not be an important factor in causing infertility in women.« less
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Rocchetti, Gabriele; Lucini, Luigi; Chiodelli, Giulia; Giuberti, Gianluca; Montesano, Domenico; Masoero, Francesco; Trevisan, Marco
2017-10-01
Cooking by boiling dry pasta could have varying degrees of influence on nutritional and functional components. In the present study, its effect on total phenolic content and antioxidant capacity, as well as on the comprehensive profile of free and bound phenolics, was investigated in six commercial gluten-free (GF) pasta products. Overall, the heat treatment caused a significant reduction (P<0.01) of the total phenolic content as well as FRAP reducing power and ORAC radical scavenging, with significant differences among the pasta samples considered. The highest values were recorded in free phenolic fraction remaining in black rice (41mggallic acid equivalents100g -1 and 25mmolTrolox Equivalents100g -1 ) and quinoa (24mggallic acid equivalents100g -1 and 14mmolTrolox Equivalents100g -1 ) cooked GF pasta. Significant correlations (P<0.01) could be found between total phenolics and both the antioxidant capacity assays performed. UHPLC-ESI/QTOF-MS mass profiling allowed confirming the spectrophotometric results, while identifying the amount of free and bound fractions. Among phenolic classes, lignans exhibited the highest decrease during the cooking process, followed by stilbenes and flavonoids. However, phenolic acids and other phenolics showed the highest stability. Furthermore, cooking by boiling strongly lowered the bound-to-free ratio of phenolic compounds, by an averaged factor ranging from 14-folds for flavonoids to 5-folds for other classes of phenolics. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Direct atomic-level insight into the active sites of a high-performance PGM-free ORR catalyst
NASA Astrophysics Data System (ADS)
Chung, Hoon T.; Cullen, David A.; Higgins, Drew; Sneed, Brian T.; Holby, Edward F.; More, Karren L.; Zelenay, Piotr
2017-08-01
Platinum group metal-free (PGM-free) metal-nitrogen-carbon catalysts have emerged as a promising alternative to their costly platinum (Pt)-based counterparts in polymer electrolyte fuel cells (PEFCs) but still face some major challenges, including (i) the identification of the most relevant catalytic site for the oxygen reduction reaction (ORR) and (ii) demonstration of competitive PEFC performance under automotive-application conditions in the hydrogen (H2)-air fuel cell. Herein, we demonstrate H2-air performance gains achieved with an iron-nitrogen-carbon catalyst synthesized with two nitrogen precursors that developed hierarchical porosity. Current densities recorded in the kinetic region of cathode operation, at fuel cell voltages greater than ~0.75 V, were the same as those obtained with a Pt cathode at a loading of 0.1 milligram of Pt per centimeter squared. The proposed catalytic active site, carbon-embedded nitrogen-coordinated iron (FeN4), was directly visualized with aberration-corrected scanning transmission electron microscopy, and the contributions of these active sites associated with specific lattice-level carbon structures were explored computationally.
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Direct atomic-level insight into the active sites of a high-performance PGM-free ORR catalyst
Chung, Hoon T.; Cullen, David A.; Higgins, Drew; ...
2017-08-04
Platinum group metal–free (PGM-free) metal-nitrogen-carbon catalysts have emerged as a promising alternative to their costly platinum (Pt)–based counterparts in polymer electrolyte fuel cells (PEFCs) but still face some major challenges, including (i) the identification of the most relevant catalytic site for the oxygen reduction reaction (ORR) and (ii) demonstration of competitive PEFC performance under automotive-application conditions in the hydrogen (H 2)–air fuel cell. We demonstrate H 2-air performance gains achieved with an iron-nitrogen-carbon catalyst synthesized with two nitrogen precursors that developed hierarchical porosity. In current densities recorded in the kinetic region of cathode operation, at fuel cell voltages greater thanmore » ~0.75 V, were the same as those obtained with a Pt cathode at a loading of 0.1 milligram of Pt per centimeter squared. The catalytic active site we proposed, carbon-embedded nitrogen-coordinated iron (FeN 4), was directly visualized with aberration-corrected scanning transmission electron microscopy, and the contributions of these active sites associated with specific lattice-level carbon structures were explored computationally.« less
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Ghosh, Sougata; Derle, Abhishek; Ahire, Mehul; More, Piyush; Jagtap, Soham; Phadatare, Suvarna D.; Patil, Ajay B.; Jabgunde, Amit M.; Sharma, Geeta K.; Shinde, Vaishali S.; Pardesi, Karishma; Dhavale, Dilip D.; Chopade, Balu A.
2013-01-01
Gnidia glauca and Dioscorea bulbifera are traditional medicinal plants that can be considered as sources of natural antioxidants. Herein we report the phytochemical analysis and free radical scavenging activity of their sequential extracts. Phenolic and flavonoid content were determined. Scavenging activity was checked against pulse radiolysis generated ABTS•+ and OH radical, in addition to DPPH, superoxide and hydroxyl radicals by biochemical methods followed by principal component analysis. G. glauca leaf extracts were rich in phenolic and flavonoid content. Ethyl acetate extract of D. bulbifera bulbs and methanol extract of G. glauca stem exhibited excellent scavenging of pulse radiolysis generated ABTS•+ radical with a second order rate constant of 2.33×106 and 1.72×106, respectively. Similarly, methanol extract of G. glauca flower and ethyl acetate extract of D. bulbifera bulb with second order rate constants of 4.48×106 and 4.46×106 were found to be potent scavengers of pulse radiolysis generated OH radical. G. glauca leaf and stem showed excellent reducing activity and free radical scavenging activity. HPTLC fingerprinting, carried out in mobile phase, chloroform: toluene: ethanol (4: 4: 1, v/v) showed presence of florescent compound at 366 nm as well as UV active compound at 254 nm. GC-TOF-MS analysis revealed the predominance of diphenyl sulfone as major compound in G. glauca. Significant levels of n-hexadecanoic acid and octadecanoic acid were also present. Diosgenin (C27H42O3) and diosgenin (3á,25R) acetate were present as major phytoconstituents in the extracts of D. bulbifera. G. glauca and D. bulbifera contain significant amounts of phytochemicals with antioxidative properties that can be exploited as a potential source for herbal remedy for oxidative stress induced diseases. These results rationalize further investigation in the potential discovery of new natural bioactive principles from these two important medicinal plants. PMID:24367520
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2012-01-01
Background Bee pollen is composed of floral pollen mixed with nectar and bee secretion that is collected by foraging honey (Apis sp.) and stingless bees. It is rich in nutrients, such as sugars, proteins, lipids, vitamins and flavonoids, and has been ascribed antiproliferative, anti-allergenic, anti-angiogenic and free radical scavenging activities. This research aimed at a preliminary investigation of the chemical constituents and free radical scavenging activity in A. mellifera bee pollen. Methods Bee pollen was directly collected from A. mellifera colonies in Nan province, Thailand, in June, 2010, whilst floral corn (Zea mays L.) pollen was collected from the nearby corn fields. The pollen was then sequentially extracted with methanol, dichloromethane (DCM) and hexane, and each crude extract was tested for free radical scavenging activity using the DPPH assay, evaluating the percentage scavenging activity and the effective concentration at 50% (EC50). The most active crude fraction from the bee pollen was then further enriched for bioactive components by silica gel 60 quick and adsorption or Sephadex LH-20 size exclusion chromatography. The purity of all fractions in each step was observed by thin layer chromatography and the bioactivity assessed by the DPPH assay. The chemical structures of the most active fractions were analyzed by nuclear magnetic resonance. Results The crude DCM extract of both the bee corn pollen and floral corn pollen provided the highest active free radical scavenging activity of the three solvent extracts, but it was significantly (over 28-fold) higher in the bee corn pollen (EC50 = 7.42 ± 0.12 μg/ml), than the floral corn pollen (EC50 = 212 ± 13.6% μg/ml). After fractionation to homogeneity, the phenolic hydroquinone and the flavone 7-O-R-apigenin were found as the minor and major bioactive compounds, respectively. Bee corn pollen contained a reasonably diverse array of nutritional components, including biotin (56.7 μg/100
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Chantarudee, Atip; Phuwapraisirisan, Preecha; Kimura, Kiyoshi; Okuyama, Masayuki; Mori, Haruhide; Kimura, Atsuo; Chanchao, Chanpen
2012-04-18
Bee pollen is composed of floral pollen mixed with nectar and bee secretion that is collected by foraging honey (Apis sp.) and stingless bees. It is rich in nutrients, such as sugars, proteins, lipids, vitamins and flavonoids, and has been ascribed antiproliferative, anti-allergenic, anti-angiogenic and free radical scavenging activities. This research aimed at a preliminary investigation of the chemical constituents and free radical scavenging activity in A. mellifera bee pollen. Bee pollen was directly collected from A. mellifera colonies in Nan province, Thailand, in June, 2010, whilst floral corn (Zea mays L.) pollen was collected from the nearby corn fields. The pollen was then sequentially extracted with methanol, dichloromethane (DCM) and hexane, and each crude extract was tested for free radical scavenging activity using the DPPH assay, evaluating the percentage scavenging activity and the effective concentration at 50% (EC50). The most active crude fraction from the bee pollen was then further enriched for bioactive components by silica gel 60 quick and adsorption or Sephadex LH-20 size exclusion chromatography. The purity of all fractions in each step was observed by thin layer chromatography and the bioactivity assessed by the DPPH assay. The chemical structures of the most active fractions were analyzed by nuclear magnetic resonance. The crude DCM extract of both the bee corn pollen and floral corn pollen provided the highest active free radical scavenging activity of the three solvent extracts, but it was significantly (over 28-fold) higher in the bee corn pollen (EC(50) = 7.42 ± 0.12 μg/ml), than the floral corn pollen (EC(50) = 212 ± 13.6% μg/ml). After fractionation to homogeneity, the phenolic hydroquinone and the flavone 7-O-R-apigenin were found as the minor and major bioactive compounds, respectively. Bee corn pollen contained a reasonably diverse array of nutritional components, including biotin (56.7 μg/100 g), invert sugar (19.9 g/100 g
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Antioxidant and free radical-scavenging activity of constituents from two Scorzonera species.
Milella, Luigi; Bader, Ammar; De Tommasi, Nunziatina; Russo, Daniela; Braca, Alessandra
2014-10-01
The aim of this study was to investigate the secondary metabolites content of Scorzonera papposa DC., an edible plant eaten in the desert region of Jordan and to assess its antioxidant and free radical-scavenging activity. By using this bioassay-oriented approach nine compounds, including the new natural compounds (6-trans-p-coumaroyl)-3-O-β-D-glucopyranosyl-2-deoxy-D-riburonic acid (1), (6-cis-p-coumaroyl)-3-O-β-D-glucopyranosyl-2-deoxy-D-riburonic acid (2a), (6-trans-p-coumaroyl)-3-O-β-D-glucopyranosyl-2-deoxy-D-riburonic acid methyl ester (3), and (6-trans-p-coumaroyl)-3-O-β-D-glucopyranosyl-(5-acetyl)-2-deoxy-D-riburonic acid (4), having the rare deoxy-D-riburonic acid moiety, were isolated. Their structures were elucidated by UV, MS, (1)H and (13)C NMR and 2D NMR. The antioxidant activity of the S. papposa pure compounds and of related derivatives isolated from another Scorzonera species (S. judaica Eig.) was also tested. The Relative Antioxidant Capacity Index (RACI) was applied as an integrated method to compare the antioxidant activities obtained using different chemical methods. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Tully, Mark A; McBride, Cairmeal; Heron, Leonnie; Hunter, Ruth F
2014-12-23
The new generation of activity monitors allow users to upload their data to the internet and review progress. The aim of this study is to validate the Fitbit Zip as a measure of free-living physical activity. Participants wore a Fitbit Zip, ActiGraph GT3X accelerometer and a Yamax CW700 pedometer for seven days. Participants were asked their opinion on the utility of the Fitbit Zip. Validity was assessed by comparing the output using Spearman's rank correlation coefficients, Wilcoxon signed rank tests and Bland-Altman plots. 59.5% (25/47) of the cohort were female. There was a high correlation in steps/day between the Fitbit Zip and the two reference devices (r = 0.91, p < 0.001). No statistically significant difference between the Fitbit and Yamax steps/day was observed (Median (IQR) 7477 (3597) vs 6774 (3851); p = 0.11). The Fitbit measured significantly more steps/day than the Actigraph (7477 (3597) vs 6774 (3851); p < 0.001). Bland-Altman plots revealed no systematic differences between the devices. Given the high level of correlation and no apparent systematic biases in the Bland Altman plots, the use of Fitbit Zip as a measure of physical activity. However the Fitbit Zip recorded a significantly higher number of steps per day than the Actigraph.
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Parolari, Giovanni; Benedini, Riccardo; Toscani, Tania
2009-08-01
The development of red pigment Zn-protoporphyrin IX (ZPP) in nitrite-free Parma hams was investigated in 5 leg muscles at several stages of processing and the activity of muscle Zn-chelatase was concurrently assayed for its potential role in ZPP formation. A steady increase of the pigment was observed throughout the manufacturing stages at mild temperatures while no development was observed during the prior cold resting phase. The enzyme was partly inactivated according to a muscle-dependent pattern, resulting in similar ZPP contents, hence color, in finished hams. It is concluded that enzyme-dependent synthesis of ZPP in nitrite-free dried hams contributes to color development, enabling muscles in dried hams to become more similar in redness than in green thighs. Therefore, checking raw meat for the enzyme content may be a means to control color formation in nitrite-free dry-cured meat derivatives.
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Giese, Ellen C; Gascon, Jacob; Anzelmo, Gianluca; Barbosa, Aneli M; da Cunha, Mário A Alves; Dekker, Robert F H
2015-01-01
β-D-Glucans are known to present antitumor, anticancer, and anti-inflammatory activities that are influenced by their own antioxidant capacity. The antioxidant activity of botryosphaeran, an exopolysaccharide of the (1 → 3;1 → 6)-β-D-glucan type produced by the Botryosphaeria rhodina MAMB-05 was evaluated and compared to some other β-D-glucans (lasiodiplodan an exocellular (1 → 6)-β-D-glucan from Lasiodiplodia theobromae, laminarin and curdlan), and oligosaccharides, disaccharides, and monosaccharides in a study of scavenging activities of free radicals in-vitro. Botryosphaeran displayed high total antioxidant activity (80%) as well as good scavenging activity against hydroxyl radical (90.6%), superoxide anion (37%), hydrogen peroxide (38%), and nitric oxide radical (90%). No reducing power, metal-chelating capacity or inhibition of lipid peroxidation was observed for these β-D-glucans. The results demonstrated that botryosphaeran exhibited effective antioxidant activity as supported by many different assays, suggesting that this β-D-glucan may serve as a source of a new bioactive compound with effective antioxidant activity. Copyright © 2014 Elsevier B.V. All rights reserved.
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Ngo, Dai-Hung; Ryu, BoMi; Kim, Se-Kwon
2014-01-15
Skin gelatin of skate (Okamejei kenojei) was hydrolyzed using Alcalase, flavourzyme, Neutrase and protamex. It was found that the Alcalase hydrolysate exhibited the highest angiotensin-I converting enzyme (ACE) inhibitory activity. Then, Alcalase hydrolysate was further hydrolyzed with protease and separated by an ultrafiltration membrane system. Finally, two peptides responsible for ACE inhibitory activity were identified to be MVGSAPGVL (829Da) and LGPLGHQ (720Da), with IC50 values of 3.09 and 4.22μM, respectively. Moreover, the free radical-scavenging activity of the purified peptides was determined in human endothelial cells. In addition, the antioxidative mechanism of the purified peptides was evaluated by protein and gene expression levels of antioxidant enzymes. The current study demonstrated that the peptides derived from skate skin gelatin could be used in the food industry as functional ingredients with potent antihypertensive and antioxidant benefits. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Dias, Douglas Fernando; Loch, Mathias Roberto; González, Alberto Durán; de Andrade, Selma Maffei; Mesas, Arthur Eumann
2017-01-01
ABSTRACT OBJECTIVE To evaluate if perceived occupational factors are associated with insufficient free-time physical activity in Brazilian public school teachers. METHODS The relationship between insufficient physical activity (< 150 minutes/week) and variables related to work was analyzed in 978 elementary and high school teachers calculating the prevalence ratio (PR) and 95% confidence interval (95%CI) in Poisson regression models, adjusted for sociodemographic and health variables. RESULTS The prevalence of insufficient physical activity was 71.9%, and this condition was associated independently with the perception of bad or regular balance between personal and professional life (PR = 1.09; 95%CI 1.01–1.18), perception that standing time affects the work (PR = 1.16; 95%CI 1.01–1.34), low or very low perception of current ability for the physical requirements of work (PR = 1.21; 95%CI 1.08–1.35), and temporary employment contract (PR = 1.13; 95%CI 1.03–1.25). The teaching of physical education was associated with lower prevalence of insufficient physical activity (PR = 0.78; 95%CI 0.64–0.95). CONCLUSIONS The perception of adverse working conditions is associated with increased prevalence of insufficient physical activity in teachers and should be considered for the promotion of physical activity in this population. PMID:28746571
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Two subunits of the 55 K porcine zona pellucida glycoprotein family are immunologically distinct
DOE Office of Scientific and Technical Information (OSTI.GOV)
Subramanian, M.G.; Yurewicz, E.C.; Sacco, A.G.
1986-03-01
The 55K glycoprotein family (ZP3) of the porcine zona pellucida is comprised of two subunits of 46 K and 45 K which can be resolved by endo-..beta..-galactosidase digestion of ZP3 followed by reversed phase HPLC on Vydac C4 resin. Gel electrophoresis revealed that the 46 K component (EBDG..cap alpha..) is approx. 95% pure and the 45 K component (EBGD..beta..) is 100% pure. In the present study, these two subunits were evaluated immunologically by RIA. Under similar reaction protocols (chloramine-T iodination procedure) comparable specific activities were obtained for EBGD..cap alpha.. (33.06 +/- 7.5 ..mu..ci/..mu..gm), EBGD..beta.. (30.45 +/- 1.6) and ZP3 (26.3more » +/- 1.3). Antibody (Ab) titration studies revealed that EBGD..cap alpha.. and ..beta.. are potent immunogens and /sup 125/I-EBGD..cap alpha.. showed minimal cross reactivity to EBGD..beta..-Ab (8% bound at 1:500 dilution), whereas, /sup 125/I-EBGD..beta.. showed a greater degree of cross reactivity to EBGD..cap alpha..-Ab (23% bound at 1:500 dilution). Maximum binding for the two labeled antigens against homologous Abs (1:500) was > 60%. Dose response studies revealed that in the /sup 125/I-EBGD..cap alpha.. vs EBGD..cap alpha.. -Ab system, the 50% intercept was 3.25 +/- 0.32 ng for EBGD..cap alpha.. and 472.43 +/- 30.26 ng for EBGD..beta.. (p < 0.01), whereas, in the /sup 125/I-EBGD..beta.. vs EBGD..beta..-Ab system the 50% intercept was 3.51 +/- 0.58 for EBGD..beta.. and 166.77 +/- 49.20 for EBGD..cap alpha.. (p < 0.01). No significant differences were observed in the slopes of the dose response curves. It is concluded that the two subunits of ZP3 possess distinct immunologic characteristics as evaluated by RIA.« less
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MyFreePACS: a free web-based radiology image storage and viewing tool.
de Regt, David; Weinberger, Ed
2004-08-01
We developed an easy-to-use method for central storage and subsequent viewing of radiology images for use on any PC equipped with Internet Explorer. We developed MyFreePACS, a program that uses a DICOM server to receive and store images and transmit them over the Web to the MyFreePACS Web client. The MyFreePACS Web client is a Web page that uses an ActiveX control for viewing and manipulating images. The client contains many of the tools found in modern image viewing stations including 3D localization and multiplanar reformation. The system is built entirely with free components and is freely available for download and installation from the Web at www.myfreepacs.com.
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Evaluation of methods to assess physical activity in free-living conditions.
Leenders, N Y; Sherman, W M; Nagaraja, H N; Kien, C L
2001-07-01
The purpose of this study was to compare different methods of measuring physical activity (PA) in women by the doubly labeled water method (DLW). Thirteen subjects participated in a 7-d protocol during which total daily energy expenditure (TDEE) was measured with DLW. Body composition, basal metabolic rate (BMR), and peak oxygen consumption were also measured. Physical activity-related energy expenditure (PAEE) was then calculated by subtracting measured BMR and the estimated thermic effect of food from TDEE. Simultaneously, over the 7 d, PA was assessed via a 7-d Physical Activity Recall questionnaire (PAR), and subjects wore secured at the waist, a Tritrac-R3D (Madison, WI), a Computer Science Application Inc. activity monitor (CSA; Shalimar, FL), and a Yamax Digi Walker-500 (Tokyo, Japan). Pearson-product moment correlations were calculated to determine the relationships among the different methods for estimating PAEE. Paired t-tests with appropriate adjustments were used to compare the different methods with DLW-PAEE. There was no significant difference between PAEE determined from PAR and DLW. The differences between the two methods ranged from -633 to 280 kcal.d(-1). Compared with DLW, PAEE determined from CSA, Tritrac, and Yamax was significantly underestimated by 59% (-495 kcal.d(-1)), 35% (-320 kcal.d(-1)) and 59% (-497 kcal.d(-1)), respectively. VO2peak explained 43% of the variation in DLW-PAEE. Although the group average for PAR-PAEE agreed with DLW-PAEE, there were differences in the methods among the subjects. PAEE determined by Tritrac, CSA, and Yamax significantly underestimate free-living PAEE in women.
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Bicarbonate-induced activation of H₂O₂ for metal-free oxidative desulfurization.
Bokare, Alok D; Choi, Wonyong
2016-03-05
Efficient oxidative desulfurization (ODS) of model oil containing dibenzothiophene (DBT) and aromatic thiophenic derivatives has been achieved at room temperature using hydrogen peroxide activation by inorganic bicarbonate (HCO3(-)). Using in-situ formation of peroxymonocarbonate as oxidant, the transformation of main model substrate DBT to corresponding DBT-sulfone was easily accomplished in biphasic reaction conditions. In the presence of water-acetonitrile polar phase, increasing the water content upto 50% decreased the extraction capacity more than 3 times, but ∼ 90% DBT oxidation was still achieved. The oxidizing capacity of bicarbonate catalyst was maintained during repeated ODS cycles, but DBT removal efficiency was critically dependent on the extraction capacity of the polar phase. Under heterogeneous reaction conditions, bicarbonate-modified ion-exchange resin achieved similar ODS activity compared to the homogeneous catalytic system. Additionally, the efficient formation of peroxymonocarbonate using gaseous CO2 precursor in alkaline conditions was also utilized for DBT oxidation. The present study proposes the NaHCO3/H2O2 catalytic system as an efficient and cheap metal-free alternative for the oxidative removal of aromatic sulfur compounds from fuel oil. Copyright © 2015 Elsevier B.V. All rights reserved.
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Overview of NASA Lewis Research Center free-piston Stirling engine activities
NASA Technical Reports Server (NTRS)
Slaby, J. G.
1984-01-01
A generic free-piston Stirling technology project is being conducted to develop technologies generic to both space power and terrestrial heat pump applications in a cooperative, cost-shared effort. The generic technology effort includes extensive parametric testing of a 1 kW free-piston Stirling engine (RE-1000), development of a free-piston Stirling performance computer code, design and fabrication under contract of a hydraulic output modification for RE-1000 engine tests, and a 1000-hour endurance test, under contract, of a 3 kWe free-piston Stirling/alternator engine. A newly initiated space power technology feasibility demonstration effort addresses the capability of scaling a free-piston Stirling/alternator system to about 25 kWe; developing thermodynamic cycle efficiency or equal to 70 percent of Carnot at temperature ratios in the order of 1.5 to 2.0; achieving a power conversion unit specific weight of 6 kg/kWe; operating with noncontacting gas bearings; and dynamically balancing the system. Planned engine and component design and test efforts are described.
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Bonin, Hélène; Delbrayelle, Dominique; Demonchaux, Patrice; Gras, Emmanuel
2010-04-21
Boronic esters have long been considered as poor partners in cross-coupling reactions with arene diazoniums. Here is reported an unprecedented application of self-activated boronic esters in a base-free cross-coupling reaction with diazonium salts under mild and user friendly conditions.
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Williams-Bey, Yolanda; Boularan, Cedric; Vural, Ali; Huang, Ning-Na; Hwang, Il-Young; Shan-Shi, Chong; Kehrl, John H.
2014-01-01
The omega-3 (ω3) fatty acid docosahexaenoic acid (DHA) can suppress inflammation, specifically IL-1β production through poorly understood molecular mechanisms. Here, we show that DHA reduces macrophage IL-1β production by limiting inflammasome activation. Exposure to DHA reduced IL-1β production by ligands that stimulate the NLRP3, AIM2, and NAIP5/NLRC4 inflammasomes. The inhibition required Free Fatty Acid Receptor (FFAR) 4 (also known as GPR120), a G-protein coupled receptor (GPR) known to bind DHA. The exposure of cells to DHA recruited the adapter protein β-arrestin1/2 to FFAR4, but not to a related lipid receptor. DHA treatment reduced the initial inflammasome priming step by suppressing the nuclear translocation of NF-κB. DHA also reduced IL-1β levels by enhancing autophagy in the cells. As a consequence macrophages derived from mice lacking the essential autophagy protein ATG7 were partially resistant to suppressive effects of DHA. Thus, DHA suppresses inflammasome activation by two distinct mechanisms, inhibiting the initial priming step and by augmenting autophagy, which limits inflammasome activity. PMID:24911523
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Event-based analysis of free-living behaviour.
Granat, Malcolm H
2012-11-01
The quantification of free-living physical activities is important in understanding how physical activity and sedentary behaviour impact on health and also on how interventions might modify free-living behaviour to enhance health. Quantification, and the terminology used, has in many ways been determined by the choice of measurement technique. The inter-related issues around measurement devices and terminology used are explored. This paper proposes a terminology and a systematic approach for the analysis of free-living activity information using event-based activity data. The event-based approach uses a flexible hierarchical classification of events and, dependent on the research question, analysis can then be undertaken on a selection of these events. The quantification of free-living behaviour is therefore the result of the analysis on the patterns of these chosen events. The application of this approach is illustrated with results from a range of published studies by our group showing how event-based analysis provides a flexible yet robust method of addressing the research question(s) and provides a deeper insight into free-living behaviour. It is proposed that it is through event-based analysis we can more clearly understand how behaviour is related to health and also how we can produce more relevant outcome measures.
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Active bialkali photocathodes on free-standing graphene substrates
Yamaguchi, Hisato; Liu, Fangze; DeFazio, Jeffrey; ...
2017-06-01
Here, the hexagonal structure of graphene gives rise to the property of gas impermeability, motivating its investigation for a new application: protection of semiconductor photocathodes in electron accelerators. These materials are extremely susceptible to degradation in efficiency through multiple mechanisms related to contamination from the local imperfect vacuum environment of the host photoinjector. Few-layer graphene has been predicted to permit a modified photoemission response of protected photocathode surfaces, and recent experiments of single-layer graphene on copper have begun to confirm these predictions for single crystal metallic photocathodes. Unlike metallic photoemitters, the integration of an ultra-thin graphene barrier film with conventionalmore » semiconductor photocathode growth processes is not straightforward. A first step toward addressing this challenge is the growth and characterization of technologically relevant, high quantum efficiency bialkali photocathodes on ultra-thin free-standing graphene substrates. Photocathode growth on free-standing graphene provides the opportunity to integrate these two materials and study their interaction. Specifically, spectral response features and photoemission stability of cathodes grown on graphene substrates are compared to those deposited on established substrates. In addition, we observed an increase of work function for the graphene encapsulated bialkali photocathode surfaces, which is predicted by our calculations. The results provide a unique demonstration of bialkali photocathodes on free-standing substrates, and indicate promise towards our goal of fabricating high-performance graphene encapsulated photocathodes with enhanced lifetime for accelerator applications.« less
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Active bialkali photocathodes on free-standing graphene substrates
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yamaguchi, Hisato; Liu, Fangze; DeFazio, Jeffrey
Here, the hexagonal structure of graphene gives rise to the property of gas impermeability, motivating its investigation for a new application: protection of semiconductor photocathodes in electron accelerators. These materials are extremely susceptible to degradation in efficiency through multiple mechanisms related to contamination from the local imperfect vacuum environment of the host photoinjector. Few-layer graphene has been predicted to permit a modified photoemission response of protected photocathode surfaces, and recent experiments of single-layer graphene on copper have begun to confirm these predictions for single crystal metallic photocathodes. Unlike metallic photoemitters, the integration of an ultra-thin graphene barrier film with conventionalmore » semiconductor photocathode growth processes is not straightforward. A first step toward addressing this challenge is the growth and characterization of technologically relevant, high quantum efficiency bialkali photocathodes on ultra-thin free-standing graphene substrates. Photocathode growth on free-standing graphene provides the opportunity to integrate these two materials and study their interaction. Specifically, spectral response features and photoemission stability of cathodes grown on graphene substrates are compared to those deposited on established substrates. In addition, we observed an increase of work function for the graphene encapsulated bialkali photocathode surfaces, which is predicted by our calculations. The results provide a unique demonstration of bialkali photocathodes on free-standing substrates, and indicate promise towards our goal of fabricating high-performance graphene encapsulated photocathodes with enhanced lifetime for accelerator applications.« less
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Moliner-Urdiales, Diego; Ortega, Francisco B; Vicente-Rodriguez, Germán; Rey-Lopez, Juan P; Gracia-Marco, Luis; Widhalm, Kurt; Sjöström, Michael; Moreno, Luis A; Castillo, Manuel J; Ruiz, Jonatan R
2010-08-01
The objective of this study is to analyse the association of objectively assessed physical activity (PA) with muscular strength and fat-free mass in adolescents, and to determine whether meeting the current PA recommendations is associated with higher levels of muscular strength and fat-free mass. The present cross-sectional study comprised 363 Spanish adolescents (180 females) aged 12.5-17.5 years. PA was assessed by accelerometry and expressed as average PA (counts/min), and min/day of inactive, light, moderate, vigorous and moderate to vigorous PA (MVPA). MVPA was dichotomized into < 60 min/day and > or = 60. Upper body muscular strength was measured with the handgrip strength test, and lower body muscular strength was measured with the standing broad jump, squat jump, counter movement jump and Abalakov tests. Fat-free mass was measured by DXA. We observed positive associations between vigorous PA and all the lower body muscular strength tests except for the counter movement jump in males. PA was not associated with fat-free mass in both males and females. Male adolescents engaged in at least 60 min/day MVPA performed better in the standing broad jump test. In conclusion, the findings of the present study suggest that only vigorous PA is associated with muscular strength, particularly lower-body muscular strength in male adolescents.
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Hacker, Eileen Danaher; Kim, Inah; Park, Chang; Peters, Tara
Fatigue and physical inactivity, critical problems facing cancer survivors, impact overall health and functioning. Our group designed a novel methodology to evaluate the temporal, dynamic patterns in real-world settings. Using real-time technology, the temporal, dynamic relationship between real-time fatigue and free-living is described and compared in cancer survivors who were treated with hematopoietic stem cell transplantation (n = 25) and age- and gender-matched healthy controls (n = 25). Subjects wore wrist actigraphs on their nondominant hand to assess free-living physical activity, measured in 1-minute epochs, over 7 days. Subjects entered real-time fatigue assessments directly into the subjective event marker of the actigraph 5 times per day. Running averages of mean 1-minute activity counts 30, 60, and 120 minutes before and after each real-time fatigue score were correlated with real-time fatigue using generalized estimating equations, RESULTS:: A strong inverse relationship exists between real-time fatigue and subsequent free-living physical activity. This inverse relationship suggests that increasing real-time fatigue limits subsequent physical activity (B range= -0.002 to -0.004; P < .001). No significant differences in the dynamic patterns of real-time fatigue and free-living physical activity were found between groups. To our knowledge, this is the first study to document the temporal and potentially causal relationship between real-time fatigue and free-living physical activity in real-world setting. These findings suggest that fatigue drives the subsequent physical activity and the relationship may not be bidirectional. Understanding the temporal, dynamic relationship may have important health implications for developing interventions to address fatigue in cancer survivors.
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Fang, Guodong; Gao, Juan; Liu, Cun; Dionysiou, Dionysios D; Wang, Yu; Zhou, Dongmei
2014-01-01
We investigated the activation of hydrogen peroxide (H2O2) by biochars (produced from pine needles, wheat, and maize straw) for 2-chlorobiphenyl (2-CB) degradation in the present study. It was found that H2O2 can be effectively activated by biochar, which produces hydroxyl radical ((•)OH) to degrade 2-CB. Furthermore, the activation mechanism was elucidated by electron paramagnetic resonance (EPR) and salicylic acid (SA) trapping techniques. The results showed that biochar contains persistent free radicals (PFRs), typically ∼ 10(18) unpaired spins/gram. Higher trapped [(•)OH] concentrations were observed with larger decreases in PFRs concentration, when H2O2 was added to biochar, indicating that PFRs were the main contributor to the formation of (•)OH. This hypothesis was supported by the linear correlations between PFRs concentration and trapped [(•)OH], as well as kobs of 2-CB degradation. The correlation coefficients (R(2)) were 0.723 and 0.668 for PFRs concentration vs trapped [(•)OH], and PFRs concentration vs kobs, respectively, when all biochars pyrolyzed at different temperatures were included. For the same biochar washed by different organic solvents (methanol, hexane, dichloromethane, and toluene), the correlation coefficients markedly increased to 0.818-0.907. Single-electron transfer from PFRs to H2O2 was a possible mechanism for H2O2 activation by biochars, which was supported by free radical quenching studies. The findings of this study provide a new pathway for biochar implication and insight into the mechanism of H2O2 activation by carbonaceous materials (e.g., activated carbon and graphite).
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Lamola, Stella Makgabo; Dzoyem, Jean Paul; Botha, Francien; van Wyk, Candice
2017-09-01
Bacterial infections of the gastrointestinal tract (GIT) cause vomiting, diarrhoea and even systemic disease. There is a need for the development of natural products into alternative and safer medicines. This study evaluated the anti-microbial activity of extracts prepared from berries, leaves, bark and roots of the edible plant Grewia flava . The anti-bacterial activity was evaluated by the broth microdilution method. Anti-oxidant activity of the most active extracts was performed by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. The cytotoxicity of the extracts was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The acetone extracts of the leaves and roots showed the best activity with MIC values as low as 0.03 mg/mL against Staphylococcus aureus and Salmonella typhimurium and 0.07 mg/mL against Bacillus cereus, Escherichia coli and Staphylococcus aureus . Quantitative analysis of the scavenging ability showed that acetone extracts exhibited good free radical scavenging activity in a dose-dependent manner. The berries extract had the highest LC 50 (lowest toxicity) of 551.68 68 µg/mL. Acetone extract of leaves and roots of Grewia flava contain anti-microbial and anti-oxidant compounds and could therefore be used as a natural product with little toxicity to host cells.
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Cellini, Nicola; McDevitt, Elizabeth A; Mednick, Sara C; Buman, Matthew P
2016-04-01
There is a growing need for free-living monitoring of the full 24 h spectrum of behaviors with a single or integrated set of sensors. The validity of field standard wearable monitors in sleep and physical activity have yet to be assessed for the complementary behavior in the context of 24 h continuous monitoring. We conducted a free-living comparison study of the Actigraph GT3X+ (GT3X+) to assess sleep parameters as compared with the Actiwatch-64 (AW-64) and concurrently, the AW-64 to assess sedentary and physical activity behaviors as compared with the GT3X+. Thirty young adults (15 female, 19.2±0.86 years) wore both monitors for 3 consecutive days and 2 consecutive nights. Agreement of sleep, sedentary, and physical activity metrics were evaluated using analyses of variance, intraclass correlation coefficients, Bland-Altman plots with associated confidence limits, mean absolute percentage of errors and equivalence tests. For sleep, the GT3X+ showed high agreement for total sleep time and sleep efficiency, but underestimated wakefulness after sleep onset and sleep onset latency relative to the AW-64. For sedentary behavior and physical activity, the AW-64 showed a moderate agreement for activity energy expenditure, but not for sedentary, light or moderate-vigorous physical activities relative to the GT3X+. Overall our results showed good agreement of the GT3X+ with AW-64 for assessing sleep but a lack of agreement between AW-64 and GT3X+ for physical activity and sedentary behaviors. These results are likely due to the monitor placement (wrist vs hip), as well as the algorithm employed to score the data. Future validation work of existing and emerging technologies that may hold promise for 24 h continuous monitoring is needed. Copyright © 2016 Elsevier Inc. All rights reserved.
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Effects of porcine zona pellucida immunocontraceptives in zoo felids.
Harrenstien, Lisa A; Munson, Linda; Chassy, Lisa M; Liu, Irwin K M; Kirkpatrick, Jay F
2004-09-01
Methods of contraception are necessary for management of zoo felids; however, the most commonly used contraceptive (melengestrol acetate implant) is associated with serious adverse reactions with long-term use. Porcine zona pellucida (pZP) vaccines are promising as contraceptives, but their safety in zoo felids has not been tested. pZP vaccine was administered to 27 female felids representing 10 species, including African lion (Panthera leo), Asian leopard (P. pardus), jaguar (P. onca), tiger (P. tigris), snow leopard (P. uncia), cougar (Felis concolor), Siberian lynx (F. lynx), Canada lynx (F. canadensis), serval (F. serval), and bobcat (F. rufus), in 15 facilities. Over 6 wk, each animal received three i.m. injections of 65 microg pZP with Freund's complete adjuvant (FCA), Freund's incomplete adjuvant, or carbopol as the adjuvant. Behavioral signs of estrus were seen in 14 of the vaccinated felids. An unacceptably high incidence of adverse reactions was seen including injection site swelling, lameness, limb swelling, or abscessation (or all) in five felids after injection with FCA as the initial adjuvant. Adverse behavioral signs, including increased irritability and aggression, were seen in four felids. Six of the felids were assayed for antibodies against pZP during the 12 mo after vaccination; all showed antibody production. Antibody levels appeared to peak 1-4 mo after vaccination began, although elevated antibody levels persisted in two animals for > 12 mo after the first injection. All vaccinated felids were ovariohysterectomized 3-13 mo after vaccination. Folliculogenesis was present in all treated animals, and there was no histopathologic evidence of inflammatory damage to ovaries. Contraceptive efficacy was not specifically evaluated in this study; however, two of the three felids housed with an intact male became pregnant during the study, one of which gave birth to healthy cubs.
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Liu, Haisheng; Ma, Changbei; Zhou, Meijuan; Chen, Hanchun; He, Hailun; Wang, Kemin
2016-11-01
This work demonstrates a novel method for DNA methyltransferase (MTase) activity detection with a quencher-free molecular beacon (MB) probe based on exonuclease (Exo) III-assisted signal amplification. In the presence of Dam MTase and DpnI endonuclease, the elaborately designed hairpin substrate (MB1) was cleaved into two parts (part A and part B). Exo III can then digest part A and release a single-stranded target of the 2-aminopurine-labeled MB (MB2). Subsequently, the MB2 can hybridize with its target to form a double-stranded structure with a protruding 3'-terminus and then trigger the digestion of MB2 by Exo III. During the digestion of MB2, the 2-aminopurine is separated from the DNA strands and released free in solution, inducing an increase of the fluorescent signal. Owing to the presence of a recessed 3'-terminus in the formed double-stranded DNA, Exo III-assisted recyclable cleavage of MB2 was achieved. Therefore, an amplified fluorescence signal was observed. Under the optimized conditions, Dam MTase can be detected in the range of 0.2-40 units/mL with a limit of detection of 0.2 units/mL and good selectivity. Furthermore, the present assay can be used for screening potential DNA MTase inhibitors. Graphical Abstract A quencher-free fluorescence assay for sensitive detection of DNA methyltransferase activity based on exonuclease III-assisted signal amplification is reported.
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Sumczynski, Daniela; Kotásková, Eva; Družbíková, Helena; Mlček, Jiří
2016-11-15
Black and red rices (Oryza sativa L.) were analysed for total flavonoids and phenolics and the HPLC profile including both free and bound phenolic fractions. Moreover, antioxidant activity and in vitro digestibility was determined. Content of flavonoids and polyphenols as well as antioxidant activity was higher in free phenolic fractions. Bound flavonoids in black rices were not significant contributors to antioxidant activity. The main free phenolics in black rices were ferulic, protocatechuic and trans-p-coumaric acids, while the major free phenolics in red rices were catechin, protocatechuic and caffeic acids. The main bound phenolics in black rices were ferulic and vanillic acids and quercetin, in red rice types, they were ferulic, syringic, trans-p-coumaric acids and quercetin. Newly, the presence of m-coumaric acid in red rices was detected. Steam cooked rices showed very high levels of organic matter digestibility, whereas red rices were significantly more digestible than black rices (p<0.05). Copyright © 2016 Elsevier Ltd. All rights reserved.
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A Flexure-Guided Piezo Drill for Penetrating the Zona Pellucida of Mammalian Oocytes.
Johnson, Wesley; Dai, Changsheng; Liu, Jun; Wang, Xian; Luu, Devin K; Zhang, Zhuoran; Ru, Changhai; Zhou, Chao; Tan, Min; Pu, Huayan; Xie, Shaorong; Peng, Yan; Luo, Jun; Sun, Yu
2018-03-01
Mammalian oocytes such as mouse oocytes have a highly elastic outer membrane, zona pellucida (ZP) that cannot be penetrated without significantly deforming the oocyte, even with a sharp micropipette. Piezo drill devices leverage lateral and axial vibration of the micropipette to accomplish ZP penetration with greatly reduced oocyte deformation. However, existing piezo drills all rely on a large lateral micropipette vibration amplitude ( 20 ) and a small axial vibration amplitude (0.1 ). The very large lateral vibration amplitude has been deemed to be necessary for ZP penetration although it also induces larger oocyte deformation and more oocyte damage. This paper reports on a new piezo drill device that uses a flexure guidance mechanism and a systematically designed pulse train with an appropriate base frequency. Both simulation and experimental results demonstrate that a small lateral vibration amplitude (e.g., 2 ) and an axial vibration amplitude as large as 1.2 were achieved. Besides achieving 100% effectiveness in the penetration of mouse oocytes (n = 45), the new piezo device during ZP penetration induced a small oocyte deformation of 3.4 versus larger than 10 using existing piezo drill devices.
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Graded activation and free energy landscapes of a muscarinic G-protein-coupled receptor.
Miao, Yinglong; McCammon, J Andrew
2016-10-25
G-protein-coupled receptors (GPCRs) recognize ligands of widely different efficacies, from inverse to partial and full agonists, which transduce cellular signals at differentiated levels. However, the mechanism of such graded activation remains unclear. Using the Gaussian accelerated molecular dynamics (GaMD) method that enables both unconstrained enhanced sampling and free energy calculation, we have performed extensive GaMD simulations (∼19 μs in total) to investigate structural dynamics of the M 2 muscarinic GPCR that is bound by the full agonist iperoxo (IXO), the partial agonist arecoline (ARC), and the inverse agonist 3-quinuclidinyl-benzilate (QNB), in the presence or absence of the G-protein mimetic nanobody. In the receptor-nanobody complex, IXO binding leads to higher fluctuations in the protein-coupling interface than ARC, especially in the receptor transmembrane helix 5 (TM5), TM6, and TM7 intracellular domains that are essential elements for GPCR activation, but less flexibility in the receptor extracellular region due to stronger binding compared with ARC. Two different binding poses are revealed for ARC in the orthosteric pocket. Removal of the nanobody leads to GPCR deactivation that is characterized by inward movement of the TM6 intracellular end. Distinct low-energy intermediate conformational states are identified for the IXO- and ARC-bound M 2 receptor. Both dissociation and binding of an orthosteric ligand are observed in a single all-atom GPCR simulation in the case of partial agonist ARC binding to the M 2 receptor. This study demonstrates the applicability of GaMD for exploring free energy landscapes of large biomolecules and the simulations provide important insights into the GPCR functional mechanism.
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Ghosh, Sougata; Derle, Abhishek; Ahire, Mehul; More, Piyush; Jagtap, Soham; Phadatare, Suvarna D; Patil, Ajay B; Jabgunde, Amit M; Sharma, Geeta K; Shinde, Vaishali S; Pardesi, Karishma; Dhavale, Dilip D; Chopade, Balu A
2013-01-01
Gnidia glauca and Dioscorea bulbifera are traditional medicinal plants that can be considered as sources of natural antioxidants. Herein we report the phytochemical analysis and free radical scavenging activity of their sequential extracts. Phenolic and flavonoid content were determined. Scavenging activity was checked against pulse radiolysis generated ABTS(•+) and OH radical, in addition to DPPH, superoxide and hydroxyl radicals by biochemical methods followed by principal component analysis. G. glauca leaf extracts were rich in phenolic and flavonoid content. Ethyl acetate extract of D. bulbifera bulbs and methanol extract of G. glauca stem exhibited excellent scavenging of pulse radiolysis generated ABTS(•+) radical with a second order rate constant of 2.33 × 10(6) and 1.72 × 10(6), respectively. Similarly, methanol extract of G. glauca flower and ethyl acetate extract of D. bulbifera bulb with second order rate constants of 4.48 × 10(6) and 4.46 × 10(6) were found to be potent scavengers of pulse radiolysis generated OH radical. G. glauca leaf and stem showed excellent reducing activity and free radical scavenging activity. HPTLC fingerprinting, carried out in mobile phase, chloroform: toluene: ethanol (4: 4: 1, v/v) showed presence of florescent compound at 366 nm as well as UV active compound at 254 nm. GC-TOF-MS analysis revealed the predominance of diphenyl sulfone as major compound in G. glauca. Significant levels of n-hexadecanoic acid and octadecanoic acid were also present. Diosgenin (C₂₇H₄₂O₃) and diosgenin (3á,25R) acetate were present as major phytoconstituents in the extracts of D. bulbifera. G. glauca and D. bulbifera contain significant amounts of phytochemicals with antioxidative properties that can be exploited as a potential source for herbal remedy for oxidative stress induced diseases. These results rationalize further investigation in the potential discovery of new natural bioactive principles from these two important
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van der Hoeven-Hangoor, E; Rademaker, C J; Paton, N D; Verstegen, M W A; Hendriks, W H
2014-07-01
Litter moisture contents vary greatly between and within practical poultry barns. The current experiment was designed to measure the effects of 8 different dietary characteristics on litter and excreta moisture content. Additionally, free water content and water activity of the excreta and litter were evaluated as additional quality measures. The dietary treatments consisted of nonstarch polysaccharide content (NSP; corn vs. wheat), particle size of insoluble fiber (coarse vs. finely ground oat hulls), viscosity of a nonfermentable fiber (low- and high-viscosity carboxymethyl cellulose), inclusion of a clay mineral (sepiolite), and inclusion of a laxative electrolyte (MgSO4). The 8 treatments were randomly assigned to cages within blocks, resulting in 12 replicates per treatment with 6 birds per replicate. Limited effects of the dietary treatments were noted on excreta and litter water activity, and indications were observed that this measurement is limited in high-moisture samples. Increasing dietary NSP content by feeding a corn-based diet (low NSP) compared with a wheat-based diet (high NSP) increased water intake, excreta moisture and free water, and litter moisture content. Adding insoluble fibers to the wheat-based diet reduced excreta and litter moisture content, as well as litter water activity. Fine grinding of the oat hulls diminished the effect on litter moisture and water activity. However, excreta moisture and free water content were similar when fed finely or coarsely ground oat hulls. The effects of changing viscosity and adding a clay mineral or laxative deviated from results observed in previous studies. Findings of the current experiment indicate a potential for excreta free water measurement as an additional parameter to assess excreta quality besides total moisture. The exact implication of this parameter warrants further investigation. © 2014 Poultry Science Association Inc.
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Razzaq, Humaira; Saira, Farhat; Yaqub, Azra; Qureshi, Rumana; Mumtaz, Misbah; Saleemi, Samia
2016-08-01
The present study investigates the interaction of citrate stabilized gold nanoparticles (12±1.5nm) (GNPs) with free radicals; 1,1-diphenyl-2-picrylhydrazyl (DPPH) stable and electrochemically generated superoxide, O2(-). Different experiments were designed to understand the interaction between GNPs and DPPH by employing cyclic voltammetry, UV-vis spectroscopy and computational chemistry using 6-311G basis set. The increase in heterogeneous rate constant, ksh, of DPPH upon addition of GNPs pointed towards possible complex formation, DPPH-GNPs which were further explained by a model assuming surface adsorption of DPPH on GNPs. Further, the model was validated by studying interaction of GNPs with a biologically important free radical, O2(-). Exciting result in terms of disappearance of anodic peak after GNPs addition confirmed that gold nanoparticles interacted with stable as well as unstable free radicals. Also, the stoichiometry of the most stable complex GNP-DPPH was determined from UV-vis spectroscopy by applying Job's method. The GNP-DPPH complex was found to be active with 46.0% reduction of the IC50 value of standard antioxidant, ascorbic acid (AA), indicating its role in enhancing antioxidant activity. Hence, this study presents a simple and potential approach to enhance the efficiency of natural antioxidants without modifying their structure, or involving the complex functionalization of GNPs with antioxidants. Copyright © 2016. Published by Elsevier B.V.
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Protective activity of green tea against free radical- and glucose-mediated protein damage.
Nakagawa, Takako; Yokozawa, Takako; Terasawa, Katsutoshi; Shu, Seiji; Juneja, Lekh Raj
2002-04-10
Protein oxidation and glycation are posttranslational modifications that are implicated in the pathological development of many age-related disease processes. This study investigated the effects of green tea extract, and a green tea tannin mixture and its components, on protein damage induced by 2,2'-azobis(2-amidinopropane) dihydrochloride (a free radical generator) and glucose in in vitro assay systems. We found that green tea extract can effectively protect against protein damage, and showed that its action is mainly due to tannin. In addition, it was shown that the chemical structures of tannin components are also involved in this activity, suggesting that the presence of the gallate group at the 3 position plays the most important role in the protective activity against protein oxidation and glycation, and that there is also a contribution by the hydroxyl group at the 5' position in the B ring and the sterical structure. These findings demonstrate the mechanisms of the usefulness of green tea in protein oxidation- and glycation-associated diseases.
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Huang, Yu-Chun; Yang, Chao-Hsun; Li, Ting-Ting; Zouboulis, Christos C; Hsu, Han-Chi
2015-10-15
Propionibacterium acnes has been considered to influence the acne lesions. The present study intended to elucidate the underlying signaling pathways of P. acnes in human sebaceous gland cells relative to the generation of proinflammatory cytokines. Cell-free extracts of P. acnes under stationary growth phase were co-incubated with human immortalized SZ95 sebocytes. Then, cell-free P. acnes extracts-induced cytokine expression was evaluated by measuring mRNA and protein levels using quantitative RT-PCR and ELISA. Changes of phosphorylated cell signaling proteins and transcription factors were measured by Western blots and Milliplex assay. The interactive molecular mechanisms of P. acnes and sebocytes were examined through use of shRNA and the specific inhibitors of signaling pathways. Cell-free extracts of P. acnes significantly stimulated secretion of interleukin (IL)-8 and IL-6 in SZ95 sebocytes. The degradation of IκB-α and increased phosphorylation of IκB-α, p38 mitogen activated protein kinase (MAPK), CREB, and STAT3 were demonstrated. Quantitative RT-PCR measurements revealed that gene expression of IL-8 and Toll-like receptor 2 (TLR2) was enhanced by cell-free extracts of P. acnes. In addition, the NF-κB inhibitor BMS345541, p38 MAPK inhibitor SB203580, or anti-TLR2 neutralizing antibody prevented cell-free P. acnes extracts-induced secretion of IL-8. Knockdown of TLR2 using shRNA exerted similar inhibitory effects on IL-8 expression. Moreover, inhibition of STAT3 activity by STA-21 enhanced P. acnes-mediated secretion of IL-8. Cell-free extracts of P. acnes are capable to activate NF-κB and p38 MAPK pathways and up-regulate secretion of IL-8 through TLR2-dependent signaling in human SZ95 sebocytes. Copyright © 2015 Elsevier Inc. All rights reserved.
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Comparison of wrist-worn and hip-worn activity monitors under free living conditions.
Hargens, Trent A; Deyarmin, Kayla N; Snyder, Kelsey M; Mihalik, Allison G; Sharpe, Lauren E
2017-04-01
Current recommendations state that individuals engage in 150 min of moderate or 75 min of vigorous intensity physical activity (PA) each week. Commercial PA monitors are becoming popular for everyday use. The accuracy of these devices, however, is not well understood. We sought to examine the accuracy of two commercial devices, one wrist and one hip-worn, under free-living conditions. Twenty-two subjects wore two commercially available devices and one ActiGraph (AG) for seven consecutive days under normal activity. Mean steps per day between all three devices differed significantly. No differences were found in moderate-to-vigorous intensity physical activity (MPVA). Daily energy expenditure (EE) also differed significantly between the AG and the commercial devices. Bland-Altman analysis found poor agreement between the AG and the commercial devices with regards to steps and EE, but good agreement in MVPA. Results suggest that the commercial devices are less accurate in estimating steps and EE. These devices did show good agreement with regards to MVPA, suggesting that they may provide useful feedback for individuals seeking to achieve the current PA guidelines for MVPA. Improvements are needed with regards to steps and EE estimation.
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NASA Technical Reports Server (NTRS)
Slaby, Jack G.
1987-01-01
A brief overview is presented of the development and technological activities of the free-piston Stirling engine. The engine started as a small scale fractional horsepower engine which demonstrated basic engine operating principles and the advantages of being hermetically sealed, highly efficient, and simple. It eventually developed into the free piston Stirling engine driven heat pump, and then into the SP-100 Space Reactor Power Program from which came the Space Power Demonstrator Engine (SPDE). The SPDE successfully operated for over 300 hr and delivered 20 kW of PV power to an alternator plunger. The SPDE demonstrated that a dynamic power conversion system can, with proper design, be balanced; and the engine performed well with externally pumped hydrostatic gas bearings.
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Vantipalli, Usha Kiran; Avula, Sai Sankar Jogendra; Enuganti, Sridevi; Bandi, Sujatha; Kakarla, Pranitha; Kuravadi, Raja Vardhan
2017-01-01
Adequate salivary flow is an important requisite in the maintenance of oral health. Salivary flow increases in response to both gustatory (taste) and mechanical (chewing) stimuli. Hence, the aim of the present study was to know the efficacy of commercially available chewing gums (sugar free and sugared) on salivary flow rate (SFR) and pH in caries-active and caries-free children. One hundred school children aged between 10 and 12 years were divided into two groups on the basis of their caries status into caries free and caries active. Unstimulated saliva was collected before start of the study. Both groups were subjected to three commercially available chewing gums (2 sugar free, 1 sugared) on consecutive days, and saliva was collected at intervals of 2 min (T2), 10 min (T10), and 30 min (T30). The pH and flow rate of saliva samples were measured before and specified time intervals after gum chewing. In both the groups, gum chewing increased the SFR, significantly at T2, and gradually declined at T30 which was significantly higher than baseline values. The pH raised significantly at T2 and gradually declined at T30 which was significantly higher than baseline values with sugar-free gums, but with sugared gums, the pH raised slightly at T2 and dropped significantly at T30. However, no statistically significant differences in pH and flow rate were noticed in both the groups. Chewing of sugar-free gums in both caries-active and caries-free children may aid in reducing the incidence of dental caries.
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Rangkadilok, Nuchanart; Sitthimonchai, Somkid; Worasuttayangkurn, Luksamee; Mahidol, Chulabhorn; Ruchirawat, Mathuros; Satayavivad, Jutamaad
2007-02-01
The protective effects of fruits and vegetables against chronic diseases have been attributed to the antioxidant properties of some secondary metabolites present in these foods. Plant polyphenols have been reported to exhibit bioactive properties, and in particular antioxidant activities. Longan seeds are found to contain high levels of some beneficial polyphenolic compounds such as corilagin, gallic acid and ellagic acid. The present study examined the free radical scavenging activity of longan seed extract by using three different assay methods. Longan extracts contained corilagin ranging from zero to 50.64 mg/g DW, gallic acid from 9.18 to 23.04 mg/g DW, and ellagic acid from 8.13 to 12.65 mg/g DW depending on the cultivars. Dried longan seed extracts of cultivar Edor contained high levels of gallic acid and ellagic acid and also exhibited the highest radical scavenging activities when comparing fresh seed and dried pulp extracts. For scavenging activity of DPPH and superoxide radicals, longan seed extract was found to be as effective as Japanese green tea extract while dried longan pulp and mulberry green tea extracts showed the least scavenging activities. In the ORAC assay, both fresh and dried longan seed also had higher activity than dried pulp and whole fruit. However, the results demonstrate that three polyphenolics may not be the major contributors of the high antioxidant activity of longan water extracts but this high activity may be due to other phenolic/flavonoid glycosides and ellagitannins present in longan fruit. In addition, longan seed also showed tyrosinase inhibitory activity with IC(50) values of 2.9-3.2 mg/ml. Therefore, the preliminary observations suggest that longan seed extract could be another potential source of potent natural dietary antioxidants and also in an application as a new natural skin-whitening agent.
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Lotufo, Bruna M; Tenório, Frank; Barradas, Penha C; Guedes, Paulo L; Lima, Sebastião S; Rocha, Michael L M; Duarte-Pinheiro, Vitor Hugo; Rodrigues, Vanessa S T; Lisboa, Patrícia C; Filgueiras, Cláudio C; Abreu-Villaça, Yael; Manhães, Alex C
2018-04-01
It is well established that chronic undernutrition has detrimental impacts on brain development and maturation. However, protein malnutrition during the period specifically encompassing the brain growth spurt has not been widely studied, particularly regarding its effects on adolescent and adult offspring behavior. Here, we assessed the effects of a protein-free diet during the 1st 10 postnatal days on the macronutrient content of the milk produced by lactating Wistar rats, on their maternal behavior, and on the offspring's behavior. Lactating dams were fed either a protein-free or a normoprotein diet from litter parturition to Postnatal Day 10 (P10). All dams received the normoprotein diet after P10. Offspring were tested in the elevated plus-maze (anxiety-like behavior), hole board arena (novelty-seeking and locomotor activity), and radial arm water maze (memory-learning) at either P40 (adolescents) or P90 (adults). The protein-free diet reduced milk protein content at P10 but not at P20. Carbohydrate and lipid contents were unaffected. Serum corticosterone levels in the offspring (at P10, P40, or P90) and dams (at P21) were not affected by the protein-free diet. Maternal behavior was also unchanged. In the offspring, no differences were observed between groups regarding anxiety-like behaviors at both ages. The protein-free diet increased adolescent locomotor activity as well as adult novelty-seeking behavior and memory performance. Our results indicate that the brain growth spurt period is particularly sensitive to protein malnutrition, showing that even a brief nutritional insult during this period can cause specific age-dependent behavioral effects on the offspring. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
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Enhanced contraception of canine zona pellucida 3 DNA vaccine via targeting DEC-205 in mice.
Wang, Ying; Zhang, Beibei; Li, Jinyao; Aipire, Adila; Li, Yijie; Zhang, Fuchun
2018-06-01
Zona pellucida 3 (ZP3) is a potential antigen for the development of contraceptive vaccines to control animal population. In this study, we designed a canine ZP3 (CZP3) DNA vaccine through targeting DEC-205 (named as pcD-scFv-CZP3c) and investigated its contraceptive effect in mice. Female BALB/c mice were intramuscularly immunized 3 times at 2 weeks intervals. After immunization, humoral and cellular immune responses were detected by ELISA and flow cytometry. The results showed that pcD-CZP3 and pcD-scFv-CZP3c induced CZP3-specific antibody (Ab) responses both in serum and vaginal secretions compared to pcDNA3.1. Additionally, compared to pcD-CZP3, pcD-scFv-CZP3c increased the levels of CZP3-specific Abs after a third immunization. Abs induced by these two DNA vaccines could bind with mice and dogs oocytes. Moreover, pcD-scFv-CZP3c enhanced the activation of CD4 + T cells characterized by the increased frequencies of CD4 + CD44 + T cells. Finally, the contraceptive effect was evaluated in the immunized mice. These two DNA vaccines significantly decreased a mean litter size of mice compared to pcDNA3.1, but pcD-scFv-CZP3c group showed the smallest mean litter size. The mean litter size of pcD-scFv-CZP3 were 3.2 ± 0.742 and 4.6 ± 1.118 in two mating tests, which were significantly lower than pcDNA3.1(P < 0.001 and P < 0.05). Our results suggest that the CZP3 DNA vaccine targeted with DEC-205 may be a potential strategy for developing a contraceptive DNA vaccine. Copyright © 2018 Elsevier Inc. All rights reserved.
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Xing, Jiali; Wang, Gang; Zhang, Qiuxiang; Liu, Xiaoming; Gu, Zhennan; Zhang, Hao; Chen, Yong Q.; Chen, Wei
2015-01-01
Antioxidant activity of lactic acid bacteria is associated with multiple health-protective effects. Traditional indexes of chemical antioxidant activities poorly reflect the antioxidant effects of these bacteria in vivo. Cellular antioxidant activity (CAA) assay was used in this study to determine the antioxidant activity of cell-free supernatants (CFSs) of 10 Lactobacillus strains. The performance of the CAA assay was compared with that of four chemical antioxidant activity assays, namely, DPPH radical scavenging, hydroxyl radical scavenging (HRS), reducing power (RP), and inhibition of linoleic acid peroxidation (ILAP). Results of the CAA assay were associated with those of DPPH and ILAP assays, but not with those of RP and HRS assays. The inter- and intra-specific antioxidant activities of CFS were characterized by chemical and CAA assays. L. rhamnosus CCFM 1107 displayed a high antioxidative effect similar to positive control L. rhamnosus GG ATCC 53103 in all of the assays. The CAA assay is a potential method for the detection of antioxidant activities of lactobacilli CFSs. PMID:25789875
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Agatonovic-Kustrin, Snezana; Morton, David W; Yusof, Ahmad P
2016-04-15
The aim of this study was to: (a) develop a simple, high performance thin layer chromatographic (HPTLC) method combined with direct 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay to rapidly assess and compare free radical scavenging activity or anti-oxidant activity for major classes of polyphenolics present in wines; and (b) to investigate relationship between free radical scavenging activity to the total polyphenolic content (TPC) and total antioxidant capacity (TAC) in the wine samples. The most potent free radical scavengers that we tested for in the wine samples were found to be resveratrol (polyphenolic non-flavonoid) and rutin (flavonoid), while polyphenolic acids (caffeic acid and gallic acid) although present in all wine samples were found to be less potent free radical scavengers. Therefore, the total antioxidant capacity was mostly affected by the presence of resveratrol and rutin, while total polyphenolic content was mostly influenced by the presence of the less potent free radical scavengers gallic and caffeic acids. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Anuthakoengkun, Areeya; Itharat, Arunporn
2014-08-01
Thai medicine plants used for Osteoarthritis of knee (OA) treatment consist of twelve plants such as Crinumn asiaticum, Cleome viscosa, Drypetes roxburghii, Piper longum, Piper nigrum, Plumbago indica, Alpinia galanga, Curcuma aromatica, Globba malaccensis, Zingiber montanum, Zingiber officinale andZingiberzerumbet. They showedhighfrequency in OA formula. To investigate inhibitory effect on LPS-induced nitric oxide (NO) release from RAW264. 7 cell and free radical scavenging activity usingDPPH assay of these ethanolic plant extracts. Plant materials were extracted by maceration in 95% ethanol. Anti-inflammatory activity were tested on LPS-induced NO production. Free radical scavenging activity was performed by DPPH assay. All of ethanolic extracts exhibited potent inhibitory effect on NO release. The ethanolic extract of Z. zerumbet exhibited the highest inhibitory effect followed by Z. montanum and G. malaccensis, respectively. Except A. galanga and C. viscosa, all extracts possessed more influential than indomethacin (IC50 = 20.32±3.23 μLg/ml), a positive control. The investigation on antioxidant activity suggested that the ethanolic extracts of D. roxburghii, Z. officinale, Z. montanum, C. aromatic, A. galanga, P indica, G malaccensis, P nigrum exhibited antioxidant activity. By means ofD. roxburghii had the highest electron donating activity,followed by Z. officinale. Moreover both extracts were more effective than BHT apositive control (EC50 = 14.04±1.95 μg/ml). Thai medicinal plants had anti-inflammatory activity and could inhibit destruction of articular cartilage that corresponded to the traditional medicine and supported using these medicinal plants for OA treatment.
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Jones, Michelle A
2017-09-12
Background : Indoor soft play can provide a safe but exciting physical activity opportunity regardless of environmental conditions. Relatively little is known about the quality or quantity of physical activity engaged in by children during indoor free soft play. The aim of this study was to evaluate the contribution indoor free soft play can make in enabling children to meet physical activity guidelines and to evaluate the effects of sex and body mass index category. Methods : Seventy-two boys and girls aged five to 10 years engaged in un-controlled indoor free soft play with a mean duration of 120.7 (27.1) min, during which physical activity was monitored using Actigraph accelerometers. Results : Children spent an average of 61.7 (24.2) min engaging in moderate to vigorous physical activity (MVPA) and 51.4% ( n = 37) achieved the recommended 60 min of MVPA through the single visit to the indoor soft play center. Boys (68.3 (25.7) min) engaged in significantly ( p < 0.05) more MVPA than girls (55.8 (21.4) min). Normal weight (65.7 (23.3) min) children engaged in significantly more MVPA than overweight children (48.0 (18.9) min). Conclusions : Attendance at a soft play indoor center has the potential to support children to engage in sufficient MVPA and overcome environmental factors that can restrict physical activity opportunities.
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Juarez, Juan C; Brown, David M; Young, David W
2014-05-19
Current Strehl ratio models for actively compensated free-space optical communications terminals do not accurately predict system performance under strong turbulence conditions as they are based on weak turbulence theory. For evaluation of compensated systems, we present an approach for simulating the Strehl ratio with both low-order (tip/tilt) and higher-order (adaptive optics) correction. Our simulation results are then compared to the published models and their range of turbulence validity is assessed. Finally, we propose a new Strehl ratio model and antenna gain equation that are valid for general turbulence conditions independent of the degree of compensation.
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Wang, Che; Cai, Zheng-Xu; You, Zhong-Lu; Guo, Hui-Shu; Shang, De-Jing; Wang, Xiao-Ling; Zhang, Liang; Ma, Li-Jie; Tan, Jun; Le, Wei-Dong; Li, Song
2014-09-01
There is increasing evidence that free radicals play an important role in neuronal damages induced by diabetes mellitus or cerebral ischemia insults. Antioxidants with free radical scavenging activities have been shown to be beneficial and neuroprotective for these pathological conditions. Here, we report free radical scavenging activity and neuroprotective potential of D138, one copper(II)/zinc(II) Schiff-base complex derived from N,N'-2(2-hydroxynaphthylmethylidene)-1,3-propanediamine. The data from three in vitro assays, 2,2-diphenyl-1-picrylhydrazyl assay, nitro blue tetrazolium assay and hydroxyl radical scavenging assay, indicated that D138 presented a potent free radical scavenging activity. The neuroprotective and antioxidative effects of D138 were further evaluated in vivo using bilateral common carotid artery occlusion (BCCAO) mouse model and streptozotocin (STZ) diabetic mouse model. Our results indicated that treatment of D138 significantly ameliorated the hippocampal neuronal damage and the oxidative stress levels in these animal models. Moreover, D138 also reversed the behavioral deficiencies induced by BCCAO or STZ, as assessed by Y-maze test and fear conditioning test. In conclusion, all these findings support that D138 exerts free radical scavenging and neuroprotective activities and has the potentials to be a potent therapeutic candidate for brain oxidative damage induced by cerebral ischemia or diabetes mellitus.
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LGR5 Activates Noncanonical Wnt Signaling and Inhibits Aldosterone Production in the Human Adrenal.
Shaikh, Lalarukh Haris; Zhou, Junhua; Teo, Ada E D; Garg, Sumedha; Neogi, Sudeshna Guha; Figg, Nichola; Yeo, Giles S; Yu, Haixiang; Maguire, Janet J; Zhao, Wanfeng; Bennett, Martin R; Azizan, Elena A B; Davenport, Anthony P; McKenzie, Grahame; Brown, Morris J
2015-06-01
Aldosterone synthesis and cellularity in the human adrenal zona glomerulosa (ZG) is sparse and patchy, presumably due to salt excess. The frequency of somatic mutations causing aldosterone-producing adenomas (APAs) may be a consequence of protection from cell loss by constitutive aldosterone production. The objective of the study was to delineate a process in human ZG, which may regulate both aldosterone production and cell turnover. This study included a comparison of 20 pairs of ZG and zona fasciculata transcriptomes from adrenals adjacent to an APA (n = 13) or a pheochromocytoma (n = 7). Interventions included an overexpression of the top ZG gene (LGR5) or stimulation by its ligand (R-spondin-3). A transcriptome profile of ZG and zona fasciculata and aldosterone production, cell kinetic measurements, and Wnt signaling activity of LGR5 transfected or R-spondin-3-stimulated cells were measured. LGR5 was the top gene up-regulated in ZG (25-fold). The gene for its cognate ligand R-spondin-3, RSPO3, was 5-fold up-regulated. In total, 18 genes associated with the Wnt pathway were greater than 2-fold up-regulated. ZG selectivity of LGR5, and its absence in most APAs, were confirmed by quantitative PCR and immunohistochemistry. Both R-spondin-3 stimulation and LGR5 transfection of human adrenal cells suppressed aldosterone production. There was reduced proliferation and increased apoptosis of transfected cells, and the noncanonical activator protein-1/Jun pathway was stimulated more than the canonical Wnt pathway (3-fold vs 1.3-fold). ZG of adrenal sections stained positive for apoptosis markers. LGR5 is the most selectively expressed gene in human ZG and reduces aldosterone production and cell number. Such conditions may favor cells whose somatic mutation reverses aldosterone inhibition and cell loss.
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Verevkin, A N; Popova, T N; Agarkov, A A; Semenikhina, A V
2015-01-01
The effect of melaxen on free radical processes and activity of superoxide dismutase and catalase in rats with type 2 diabetes mellitus (T2DM) has been investigated. It was established that melaxen administration to diabetic rats caused a decrease of the intensity of free radical processes as evidenced a decrease of the lipid peroxidation primary products content and biochemiluminescence parameters. The activity of the antioxidant enzymes changed towards normal values. These effects were probably induced by the correction of the melatonin level at the result of the melaxen action.
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45 CFR 84.33 - Free appropriate public education.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 45 Public Welfare 1 2011-10-01 2011-10-01 false Free appropriate public education. 84.33 Section..., Elementary, and Secondary Education § 84.33 Free appropriate public education. (a) General. A recipient that operates a public elementary or secondary education program or activity shall provide a free appropriate...
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45 CFR 84.33 - Free appropriate public education.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 45 Public Welfare 1 2014-10-01 2014-10-01 false Free appropriate public education. 84.33 Section..., Elementary, and Secondary Education § 84.33 Free appropriate public education. (a) General. A recipient that operates a public elementary or secondary education program or activity shall provide a free appropriate...
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45 CFR 84.33 - Free appropriate public education.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 45 Public Welfare 1 2013-10-01 2013-10-01 false Free appropriate public education. 84.33 Section..., Elementary, and Secondary Education § 84.33 Free appropriate public education. (a) General. A recipient that operates a public elementary or secondary education program or activity shall provide a free appropriate...
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45 CFR 84.33 - Free appropriate public education.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 45 Public Welfare 1 2012-10-01 2012-10-01 false Free appropriate public education. 84.33 Section..., Elementary, and Secondary Education § 84.33 Free appropriate public education. (a) General. A recipient that operates a public elementary or secondary education program or activity shall provide a free appropriate...
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45 CFR 84.33 - Free appropriate public education.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 45 Public Welfare 1 2010-10-01 2010-10-01 false Free appropriate public education. 84.33 Section..., Elementary, and Secondary Education § 84.33 Free appropriate public education. (a) General. A recipient that operates a public elementary or secondary education program or activity shall provide a free appropriate...
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NASA Astrophysics Data System (ADS)
Larasati Tres Ayu Putranti, Monika; Kompiang Wirawan, Sang; Made Bendiyasa, I.
2018-01-01
Adsorption of free fatty acid (FFA) in low-grade cooking oil using active natural zeolite adsorbent was done as an effort to improve the quality of low-grade cooking oil so that it can fulfill the standard of fried oil which has been set on SNI 01-3741-2013. Adsorption was carried out with natural zeolite which activated with HCl and NaOH solution followed by the calcination process. The results showed that the NaOH activated zeolite decreased FFA content in low-grade cooking oil more than the HCl activated natural zeolite, with optimum NaOH concentration was 0.75 M. In the adsorption equilibrium analysis with temperature variation (25 °C, 40 °C, 80 °C ), obtained that adsorption of FFA with NaOH activated natural zeolite follows Adsorption Isotherm Freundlich Model with equilibrium constant value was 20,5873; 0,9629 dan 0,8053.
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Cove, Michael V.; Gardner, Beth; Simons, Theodore R.; Kays, Roland; O'Connell, Allan F.
2017-01-01
Feral and free-ranging domestic cats (Felis catus) can have strong negative effects on small mammals and birds, particularly in island ecosystems. We deployed camera traps to study free-ranging cats in national wildlife refuges and state parks on Big Pine Key and Key Largo in the Florida Keys, USA, and used spatial capture–recapture models to estimate cat abundance, movement, and activities. We also used stable isotope analyses to examine the diet of cats captured on public lands. Top population models separated cats based on differences in movement and detection with three and two latent groups on Big Pine Key and Key Largo, respectively. We hypothesize that these latent groups represent feral, semi-feral, and indoor/outdoor house cats based on the estimated movement parameters of each group. Estimated cat densities and activity varied between the two islands, with relatively high densities (~4 cats/km2) exhibiting crepuscular diel patterns on Big Pine Key and lower densities (~1 cat/km2) exhibiting nocturnal diel patterns on Key Largo. These differences are most likely related to the higher proportion of house cats on Big Pine relative to Key Largo. Carbon and nitrogen isotope ratios from hair samples of free-ranging cats (n = 43) provided estimates of the proportion of wild and anthropogenic foods in cat diets. At the population level, cats on both islands consumed mostly anthropogenic foods (>80% of the diet), but eight individuals were effective predators of wildlife (>50% of the diet). We provide evidence that cat groups within a population move different distances, exhibit different activity patterns, and that individuals consume wildlife at different rates, which all have implications for managing this invasive predator.
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Hillitt, K L; Jenkins, R E; Spiller, O B; Beeton, M L
2017-03-01
The susceptibility of the cell wall-free bacterial pathogens Ureaplasma spp. to Manuka honey was examined. The minimum inhibitory concentration (MIC) of Manuka honey for four Ureaplasma urealyticum and four Ureaplasma parvum isolates was determined. Sensitivity to honey was also compared to clinical isolates with resistance to tetracycline, macrolide and fluoroquinolone antibiotics. Finally step-wise resistance training was utilized in an attempt to induce increased tolerance to honey. The MIC was dependent on the initial bacterial load with 7·5 and 18·0% w/v honey required to inhibit U. urealyticum at 1 and 10 6 colour changing units (CCU), respectively, and 4·8 and 15·3% w/v required to inhibit U. parvum at 1 and 10 6 CCU respectively. MIC values were consistently lower for U. parvum compared with U. urealyticum. Antimicrobial activity was seen against tetracycline-resistant, erythromycin-resistant and ciprofloxacin-resistant isolates at 10 5 CCU. No resistance to honey was observed with 50 consecutive challenges at increasing concentrations of honey. This is the first report of the antimicrobial activity of Manuka honey against a cell wall-free bacterial pathogen. The antimicrobial activity was retained against antibiotic-resistant strains and it was not possible to generate resistant mutants. Manuka honey is known to have a broad spectrum of antimicrobial activity, with the bacterial cell wall being suggested as a predominant site of action. This study has demonstrated that Manuka honey has activity against Ureaplasma spp., a genus of cell wall-free bacteria which are intrinsically resistant to many available antibiotics making treatment inherently difficult. This is the first report of the antimicrobial activity of Manuka honey against a bacterial pathogen, in the absence of a cell well and opens scope for the use of components of Manuka honey as a therapeutic among Ureaplasma infections. © 2016 The Society for Applied Microbiology.
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ERIC Educational Resources Information Center
Kaminski, Robert
1991-01-01
Describes two classroom activities that were developed to promote a whole language approach to listening, speaking, reading, and writing. One involved fifth grade students who wrote legends that other students paid to read and evaluate, and the other involved an eighth grade English class who gave free poetry readings in a coffee house setting.…
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ERIC Educational Resources Information Center
Shih, Ching-Hsiang
2011-01-01
This study assessed whether two persons with developmental disabilities would be able to actively perform simple occupational activities by controlling their favorite environmental stimulation using battery-free wireless mice with a newly developed object location detection program (OLDP, i.e., a new software program turning a battery-free…
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Saeterbakken, Atle H; Andersen, Vidar; van den Tillaar, Roland
2016-04-01
The purpose of the study was to compare kinematic muscle activation when performing 6 repetition maximum (6RM) squats using constant (free weights) or variable resistance (free weights + elastic bands). Twenty recreationally trained women were recruited with 4.6 ± 2.1 years of resistance training experience and a relative strength (6RM/body mass) of 1.1. After a familiarization session identifying the 6RM loads, the participants performed 6RM squats using constant and variable resistance in a randomized order. The total resistance in the variable resistance group was similar to the constant resistance in the presticking region (98%), but greater in the sticking region (105%) and the poststicking region (113%). In addition, the presticking barbell velocity was 21.0% greater using variable than constant resistance, but 22.8% lower in the poststicking region. No significant differences in muscle electromyographic activity, time occurrence, and vertical displacement between the squat modalities were observed, except for higher barbell displacement poststicking using variable resistance. It was concluded that, due to differences in total resistance in the different regions performing variable compared with constant resistance, greater barbell velocity was observed in the presticking region and lower resistance was observed in the poststicking region. However, the extra resistance in the sticking and poststicking regions during the variable resistance modality did not cause increased muscle activity. When performing squats with heavy resistance, the authors recommend using variable resistance, but we suggest increasing the percentage resistance from the elastic bands or using chains.
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Calliste, C A; Trouillas, P; Allais, D P; Simon, A; Duroux, J L
2001-07-01
In an effort to discover new antioxidant natural compounds, seven plants that grow in France (most of them in the Limousin countryside) were screened. Among these plants, was the extensively studied Vitis vinifera as reference. For each plant, sequential percolation was realized with five solvents of increasing polarities (hexane, chloroform, ethyl acetate, methanol, and water). Free radical scavenging activities were examined in different systems using electron spin resonance (ESR) spectroscopy. These assays were based on the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH), the hydroxyl radicals generated by a Fenton reaction, and the superoxide radicals generated by the X/XO system. Antiproliferative behavior was studied on B16 melanoma cells. ESR results showed that three plants (Castanea sativa, Filipendula ulmaria, and Betula pendula) possessed, for the most polar fractions (presence of phenolic compounds), high antioxidant activities in comparison with the Vitis vinifera reference. Gentiana lutea was the only one that presented a hydroxyl scavenging activity for the ethyl acetate and chloroform fractions. The antiproliferative test results showed that the same three plants are the most effective, but for the apolar fractions (chloroform and hexane).
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Nash, Anthony; Birch, Helen L; de Leeuw, Nora H
2017-02-01
The zinc-dependent Matrix Metalloproteinases (MMPs) found within the extracellular matrix (ECM) of vertebrates are linked to pathological processes such as arthritis, skin ulceration and cancer. Although a general backbone proteolytic mechanism is understood, crystallographic data continue to suggest an active site that is too narrow to encompass the respective substrate. We present a fully parameterised Molecular Dynamics (MD) study of the structural properties of an MMP-1-collagen crystallographic structure (Protein Data Bank - 4AUO), followed by an exploration of the free energy surface of a collagen polypeptide chain entering the active site, using a combined meta-dynamics and umbrella sampling (MDUS) approach. We conclude that the interactions between MMP-1 and the collagen substrate are in good agreement with a number of experimental studies. As such, our unrestrained MD simulations and our MDUS results, which indicate an energetic barrier for a local uncoiling and insertion event, can inform future investigations of the collagen-peptide non-bonded association steps with the active site prior to proteolytic mechanisms. The elucidation of such free energy barriers provides a better understanding of the role of the enzyme in the ECM and is important in the design of future MMP inhibitors.
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Ben Ammar, Rebai; Miyamoto, Tomofumi; Chekir-Ghedira, Leila; Ghedira, Kamel; Lacaille-Dubois, Marie-Aleth
2018-03-13
From the butanolic and the ethyl acetate extracts of Rhamnus alaternus L root bark and leaves, three new anthraquinone glycosides, alaternosides A-C (1,4,6,8 tetrahydroxy-3 methyl anthraquinone 1-O-ß-D-glucopyranosyl-4,6-di-O-α-L-rhamnopyranoside (1); 1,2,6,8 tetrahydroxy-3 methyl anthraquinone 8-O-ß-D-glucopyranoside (2) and 1, 6 dihydroxy-3 methyl 6 [2'-Me (heptoxy)] anthraquinone (3)) were isolated and elucidated together with the two known anthraquinone glycosides, Physcion-8-O-rutinoside (4) and emodin-6-O-α-L-rhamnoside (5) as well as with the known kaempferol-7-methylether (6), β-sitosterol (7) and β-sitosterol-3-O-glycoside (8). Their chemical structures were elucidated using spectroscopic methods (1D-, 2D-NMR and FAB-MS). Free radical scavenging activity of the isolated compounds was evaluated by their ability to scavenge DPPH . free radicals. Compounds (3), (4) and (6) showed the highest activity with IC 50 values of 9.46, 27.68 and 2.35 μg/mL, respectively.
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Lipert, Anna; Jegier, Anna
2017-07-01
To compare physical activity (PA) measured by 4 methods in adults under free-living conditions in relation to selected demographic and anthropometric variables. Cohort study. Department of Sports Medicine. Clinically healthy men (81) and women (69) aged 45 to 64 years. Physical activity monitoring for 7 consecutive days under free-living conditions by pedometer (P) and accelerometer (A) simultaneously and PA questionnaires: International Physical Activity Questionnaire (IPAQ) and Seven-Day Physical Activity Questionnaire Recall (SDPAR) completed after the 7-day PA. Comparison of PA measured by pedometer, IPAQ, and SDPAR with accelerometer with regard to age, body mass, gender, and obesity type. Total energy expenditure (EE) by IPAQ was higher than A (P < 0.001) in both groups regardless of age, body mass, or obesity type. Mean EE value by P was greater than A (P < 0.001) in central-obesity males and lower than A (P < 0.001) in central-obesity females. There were differences in step counts in women, unnoticed in men. SDPAR overestimated total EE in gynoid-obesity males and in central-obesity females compared with A. Ninety-five percent CI was the largest around IPAQ compared with P and SDPAR, with SDPAR showing the best agreement with A. Body mass and obesity type influenced PA measurements. To monitor PA, it is recommended to use pedometer in normal bodyweight and overweight groups while accelerometer is advisable in obese subjects. A combined approach of objective and subjective PA monitoring tools is preferable.
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Analysis of ZP1 gene reveals differences in zona pellucida composition in carnivores.
Moros-Nicolás, C; Leza, A; Chevret, P; Guillén-Martínez, A; González-Brusi, L; Boué, F; Lopez-Bejar, M; Ballesta, J; Avilés, M; Izquierdo-Rico, M J
2018-01-01
The zona pellucida (ZP) is an extracellular envelope that surrounds mammalian oocytes. This coat participates in the interaction between gametes, induction of the acrosome reaction, block of polyspermy and protection of the oviductal embryo. Previous studies suggested that carnivore ZP was formed by three glycoproteins (ZP2, ZP3 and ZP4), with ZP1 being a pseudogene. However, a recent study in the cat found that all four proteins were expressed. In the present study, in silico and molecular analyses were performed in several carnivores to clarify the ZP composition in this order of mammals. The in silico analysis demonstrated the presence of the ZP1 gene in five carnivores: cheetah, panda, polar bear, tiger and walrus, whereas in the Antarctic fur seal and the Weddell seal there was evidence of pseudogenisation. Molecular analysis showed the presence of four ZP transcripts in ferret ovaries (ZP1, ZP2, ZP3 and ZP4) and three in fox ovaries (ZP2, ZP3 and ZP4). Analysis of the fox ZP1 gene showed the presence of a stop codon. The results strongly suggest that all four ZP genes are expressed in most carnivores, whereas ZP1 pseudogenisation seems to have independently affected three families (Canidae, Otariidae and Phocidae) of the carnivore tree.
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In vitro evaluation of free radical scavenging activity of Codariocalyx motorius root extract.
Chidambaram, Uma; Pachamuthu, Vanitha; Natarajan, Suganya; Elango, Bhakkiyalakshmi; Suriyanarayanan; Ramkumar, Kunga Mohan
2013-03-01
To determine the phenolic content in Codariocalyx motorius root extract and to evaluate its antioxidant properties using various in vitro assay systems. The antioxidant activity was evaluated based on scavenging of 1,1-diphenyl-2-picrylhydrazyl, hydroxyl radicals, superoxide anions, nitric oxide, hydrogen peroxide, peroxynitrite, reducing power and by inhibition of lipid peroxidation which was estimated in terms of thiobarbituric acid reactive substances. The root extract of the Codariocalyx motorius (C. motorius) exhibited potent total antioxidant activity that increased with increasing amount of extract concentration, which was compared with standard drug such as quercetin, butylated hydroxytoluene, tocopherol at different concentrations. The different concentrations of the extracts showed inhibition on lipid peroxidation. In addition, the extracts had effective reducing power, free radical scavenging, super oxide anion scavenging, nitric oxide scavenging, lipid peroxidation, and total phenolic content depending on concentration. High correlation between total phenolic contents and scavenging potential of different reactive oxygen species (r(2)=0.831-0.978) indicated the polyphenols as the main antioxidants. Codariocalyx motorius (C. motorius) root possess the highly active antioxidant substance which can be used for the treatment of oxidative stress-related diseases. Copyright © 2013 Hainan Medical College. Published by Elsevier B.V. All rights reserved.
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Rawat, Vikas S; Bathini, Thulasiram; Govardan, S; Sreedhar, Bojja
2014-09-14
Propargylamines are synthesized via metal-free activation of the C-halogen bond of dihalomethanes and the C-H bond of terminal alkynes in a three-component coupling without catalyst or additional base and under mild reaction conditions. The dihalomethanes are used both as solvents as well as precursors for the methylene fragment (C1) in the final product. The scope of the reaction and the influence of various reaction variables has been investigated. A plausible reaction mechanism is proposed and the involvement of various intermediates that can be generated in situ in the process is discussed. The metal-free conditions also make this protocol environmentally benign and atom economical.
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NASA Astrophysics Data System (ADS)
McCoy, Michael J.; Habermann, Timothy J.; Hanke, Craig J.; Adar, Fran; Campbell, William B.; Nithipatikom, Kasem
1999-04-01
We developed a confocal Raman microspectroscopic technique to study ligand-receptor bindings in single cells using Raman-labeled ligands and surface-enhanced Raman scattering (SERS). The adrenal zona glomerulosa (ZG) cells were used as a model in this study. ZG cells have a high density of angiotensin II (AII) receptors on the cellular membrane. There are two identified subtypes of AII receptors,namely AT1 and AT2 receptors. AII is a peptidic hormone, which upon binding to its receptors, stimulates the release of aldosterone from ZG cells. The cellular localization of these receptors subtypes was detected in single ZG cells by using immunocomplexation of receptors with specific antibodies and confocal Raman microspectroscopy. In the binding study, we used biotin-labeled AII to bind to its receptors in ZG cells. Then, avidin and Raman-labeled AII. The binding was measure directly on the single ZG cells. The results showed that the binding was displaced with unlabeled AII and specific AII antagonists. This is a rapid and sensitive technique for detection of cellular ligand bindings as well as antagonists screening in drug discovery.
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Metabolic Activation of Sulfur Mustard Leads to Oxygen Free Radical Formation
2012-01-01
spin trapping results that demonstrated the enzymatic reduction of sulfur mustard sulfonium ions to carbon-based free radicals using an in vitro system ...BMPO EPR signals were reduced or eliminated when mustard carbon radical production was impeded by systematically removing system components, indicating...referred to as complete incubation mixture. EPR spectrometry Mustard-related carbon or oxygen free radical production was recorded using a Bruker EMX Plus
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Maurer, Manuela; de Beer, Stephanie B A; Oostenbrink, Chris
2016-04-15
The periplasmic oligopeptide binding protein A (OppA) represents a well-known example of water-mediated protein-ligand interactions. Here, we perform free-energy calculations for three different ligands binding to OppA, using a thermodynamic integration approach. The tripeptide ligands share a high structural similarity (all have the sequence KXK), but their experimentally-determined binding free energies differ remarkably. Thermodynamic cycles were constructed for the ligands, and simulations conducted in the bound and (freely solvated) unbound states. In the unbound state, it was observed that the difference in conformational freedom between alanine and glycine leads to a surprisingly slow convergence, despite their chemical similarity. This could be overcome by increasing the softness parameter during alchemical transformations. Discrepancies remained in the bound state however, when comparing independent simulations of the three ligands. These difficulties could be traced to a slow relaxation of the water network within the active site. Fluctuations in the number of water molecules residing in the binding cavity occur mostly on a timescale larger than the simulation time along the alchemical path. After extensive simulations, relative binding free energies that were converged to within thermal noise could be obtained, which agree well with available experimental data.
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Phosphorylation of zona occludens-2 by protein kinase C epsilon regulates its nuclear exportation.
Chamorro, David; Alarcón, Lourdes; Ponce, Arturo; Tapia, Rocio; González-Aguilar, Héctor; Robles-Flores, Martha; Mejía-Castillo, Teresa; Segovia, José; Bandala, Yamir; Juaristi, Eusebio; González-Mariscal, Lorenza
2009-09-01
Here, we have analyzed the subcellular destiny of newly synthesized tight junction protein zona occludens (ZO)-2. After transfection in sparse cells, 74% of cells exhibit ZO-2 at the nucleus, and after 18 h the value decreases to 17%. The mutation S369A located within the nuclear exportation signal 1 of ZO-2 impairs the nuclear export of the protein. Because Ser369 represents a putative protein kinase C (PKC) phosphorylation site, we tested the effect of PKC inhibition and stimulation on the nuclear export of ZO-2. Our results strongly suggest that the departure of ZO-2 from the nucleus is regulated by phosphorylation at Ser369 by novel PKCepsilon. To test the route taken by ZO-2 from synthesis to the plasma membrane, we devised a novel nuclear microinjection assay in which the nucleus served as a reservoir for anti-ZO-2 antibody. Through this assay, we demonstrate that a significant amount of newly synthesized ZO-2 goes into the nucleus and is later relocated to the plasma membrane. These results constitute novel information for understanding the mechanisms that regulate the intracellular fate of ZO-2.
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Aggarwal, Bharat B; Yuan, Wei; Li, Shiyou; Gupta, Subash C
2013-09-01
Turmeric, a dried powder derived from the rhizome of Curcuma longa, has been used for centuries in certain parts of the world and has been linked to numerous biological activities including antioxidant, anti-inflammatory, anticancer, antigrowth, anti-arthritic, anti-atherosclerotic, antidepressant, anti-aging, antidiabetic, antimicrobial, wound healing, and memory-enhancing activities. One component of turmeric is curcumin, which has been extensively studied, as indicated by more than 5600 citations, most of which have appeared within the past decade. Recent research has identified numerous chemical entities from turmeric other than curcumin. It is unclear whether all of the activities ascribed to turmeric are due to curcumin or whether other compounds in turmeric can manifest these activities uniquely, additively, or synergistically with curcumin. However, studies have indicated that turmeric oil, present in turmeric, can enhance the bioavailability of curcumin. Studies over the past decade have indicated that curcumin-free turmeric (CFT) components possess numerous biological activities including anti-inflammatory, anticancer, and antidiabetic activities. Elemene derived from turmeric is approved in China for the treatment of cancer. The current review focuses on the anticancer and anti-inflammatory activities exhibited by CFT and by some individual components of turmeric, including turmerin, turmerone, elemene, furanodiene, curdione, bisacurone, cyclocurcumin, calebin A, and germacrone. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Razak, Lubna Abdul; Yoong, Sze Lin; Wiggers, John; Morgan, Philip J; Jones, Jannah; Finch, Meghan; Sutherland, Rachel; Lecathelnais, Christophe; Gillham, Karen; Clinton-McHarg, Tara; Wolfenden, Luke
2018-04-04
Increasing the frequency of periods of outdoor free-play in childcare may represent an opportunity to increase child physical activity. This study aimed to assess the efficacy of scheduling multiple periods of outdoor free-play in increasing the time children spend in moderate-to-vigorous physical activity (MVPA) while attending childcare. The study employed a cluster randomised controlled trial design involving children aged 3 to 6 years, attending ten childcare services in the Hunter New England region of New South Wales, Australia. Five services were randomised to receive the intervention and five to a control condition. The intervention involved services scheduling three separate periods of outdoor free-play from 9 am to 3 pm per day, each at least 15 min in duration, with the total equivalent to their usual daily duration of outdoor play period. Control services implemented the usual single continuous period of outdoor free-play over this time. The primary outcome, children's moderate-to-vigorous physical activity (MVPA) while in care per day, was measured over 5 days via accelerometers at baseline and at 3 months post baseline. Secondary outcomes included percentage of time spent in MVPA while in care per day, total physical activity while in care per day and documented child injury, a hypothesised potential unintended adverse event. Childcare services and data collectors were not blind to the experimental group allocation. Parents of 439 (71.6%) children attending participating childcare services consented for their child to participate in the trial. Of these, 316 (72.0%) children provided valid accelerometer data at both time points. Relative to children in control services, mean daily minutes of MVPA in care was significantly greater at follow-up among children attending intervention services (adjusted difference between groups 5.21 min, 95% CI 0.59-9.83 p = 0.03). Percentage of time spent in MVPA in care per day was also greater at follow-up among
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Bittner, George D; Denison, Michael S; Yang, Chun Z; Stoner, Matthew A; He, Guochun
2014-12-04
Chemicals that have estrogenic activity (EA) can potentially cause adverse health effects in mammals including humans, sometimes at low doses in fetal through juvenile stages with effects detected in adults. Polycarbonate (PC) thermoplastic resins made from bisphenol A (BPA), a chemical that has EA, are now often avoided in products used by babies. Other BPA-free thermoplastic resins, some hypothesized or advertised to be EA-free, are replacing PC resins used to make reusable hard and clear thermoplastic products such as baby bottles. We used two very sensitive and accurate in vitro assays (MCF-7 and BG1Luc human cell lines) to quantify the EA of chemicals leached into ethanol or water/saline extracts of fourteen unstressed or stressed (autoclaving, microwaving, UV radiation) thermoplastic resins. Estrogen receptor (ER)-dependent agonist responses were confirmed by their inhibition with the ER antagonist ICI 182,780. Our data showed that some (4/14) unstressed and stressed BPA-free thermoplastic resins leached chemicals having significant levels of EA, including one polystyrene (PS), and three Tritan™ resins, the latter reportedly EA-free. Exposure to UV radiation in natural sunlight resulted in an increased release of EA from Tritan™ resins. Triphenyl-phosphate (TPP), an additive used to manufacture some thermoplastic resins such as Tritan™, exhibited EA in both MCF-7 and BG1Luc assays. Ten unstressed or stressed glycol-modified polyethylene terephthalate (PETG), cyclic olefin polymer (COP) or copolymer (COC) thermoplastic resins did not release chemicals with detectable EA under any test condition. This hazard survey study assessed the release of chemicals exhibiting EA as detected by two sensitive, widely used and accepted, human cell line in vitro assays. Four PC replacement resins (Tritan™ and PS) released chemicals having EA. However, ten other PC-replacement resins did not leach chemicals having EA (EA-free-resins). These results indicate that PC
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NASA Technical Reports Server (NTRS)
Barghouty, A. F.; Falconer, D. A.; Adams, J. H., Jr.
2010-01-01
This presentation describes a new forecasting tool developed for and is currently being tested by NASA s Space Radiation Analysis Group (SRAG) at JSC, which is responsible for the monitoring and forecasting of radiation exposure levels of astronauts. The new software tool is designed for the empirical forecasting of M and X-class flares, coronal mass ejections, as well as solar energetic particle events. Its algorithm is based on an empirical relationship between the various types of events rates and a proxy of the active region s free magnetic energy, determined from a data set of approx.40,000 active-region magnetograms from approx.1,300 active regions observed by SOHO/MDI that have known histories of flare, coronal mass ejection, and solar energetic particle event production. The new tool automatically extracts each strong-field magnetic areas from an MDI full-disk magnetogram, identifies each as an NOAA active region, and measures a proxy of the active region s free magnetic energy from the extracted magnetogram. For each active region, the empirical relationship is then used to convert the free magnetic energy proxy into an expected event rate. The expected event rate in turn can be readily converted into the probability that the active region will produce such an event in a given forward time window. Descriptions of the datasets, algorithm, and software in addition to sample applications and a validation test are presented. Further development and transition of the new tool in anticipation of SDO/HMI is briefly discussed.
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2017-01-01
Background: Indoor soft play can provide a safe but exciting physical activity opportunity regardless of environmental conditions. Relatively little is known about the quality or quantity of physical activity engaged in by children during indoor free soft play. The aim of this study was to evaluate the contribution indoor free soft play can make in enabling children to meet physical activity guidelines and to evaluate the effects of sex and body mass index category. Methods: Seventy-two boys and girls aged five to 10 years engaged in un-controlled indoor free soft play with a mean duration of 120.7 (27.1) min, during which physical activity was monitored using Actigraph accelerometers. Results: Children spent an average of 61.7 (24.2) min engaging in moderate to vigorous physical activity (MVPA) and 51.4% (n = 37) achieved the recommended 60 min of MVPA through the single visit to the indoor soft play center. Boys (68.3 (25.7) min) engaged in significantly (p < 0.05) more MVPA than girls (55.8 (21.4) min). Normal weight (65.7 (23.3) min) children engaged in significantly more MVPA than overweight children (48.0 (18.9) min). Conclusions: Attendance at a soft play indoor center has the potential to support children to engage in sufficient MVPA and overcome environmental factors that can restrict physical activity opportunities. PMID:28895904
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NASA Astrophysics Data System (ADS)
Darsih, C.; Apriyana, W.; Nur Hayati, S.; Taufika Rosyida, V.; Hernawan; Dewi Poeloengasih, C.
2017-02-01
Water soluble polysaccharide is one of the important phytochemical in Ganoderma lucidum K. Phytochemicals in the plants, microorganisms, and plants were affected by internal and external factors. The objective of the research was to evaluate the effect of elevation on the water-soluble polysaccharides and its DPPH radical scavenging activity. We found that the water-polysaccharides in mushroom from Godean (elevation <100 mamsl) (35.28 ± 0.31%) higher than Kaliurang (elevation 800 mamsl) (25.17 ± 1.85%). The DPPH free radical scavenging activity of Ganoderma lucidum K from Godean (IC50 11.5 ± 0.29 mg/mL) higher than Kaliurang (IC50 14.4 ± 0.27%).
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Oh, Sang-seok; Kim, Donghyeok; Kim, Dong-Hee; Chang, Hong Hee; Sohn, Kyung-Cheol; Kim, Kyo Hyun; Jung, Sung Hoo; Lee, Byoung Kil; Kim, Joo Heon; Kim, Kwang Dong
2012-10-01
N-myc downstream-regulated gene 2 (NDRG2) has been studied for its inhibitory effects against growth and metastasis of many tumor cell types. In this study, we showed NDRG2 expression was correlated with favorable recurrence-free survival of patients with breast cancer and inhibited metastasis of breast cancer cells (4T1). NDRG2 expression was examined in 189 breast carcinoma tissues and paired normal breast tissues using immunohistochemistry. Histological and clinicopathological data were correlated using Pearson's chi-square test of independence. NDRG2 expression in human breast cancer tissues was inversely associated with lymph node metastasis and pTNM stage. Furthermore, patients with breast cancer with a high level of NDRG2 expression showed favorable recurrence-free survival (P = 0.038). To study the effect of NDRG2 on metastasis in vivo, we established an NDRG2-overexpressing mouse breast cancer cell line (4T1-NDRG2) and measured the metastasis and survival of 4T1-NDRG2 tumor-bearing mice. To test whether transforming growth factor β (TGF-β)- mediated metastasis of 4T1 was inhibited by NDRG2 expression, TGF-Smad-binding element (SBE)-luciferase activity and/or measurement of active TGF-β were performed in cell or tumor tissue level. 4T1-NDRG2 cells grew gradually and showed less metastatic activity in vivo and low invasiveness in vitro. 4T1-NDRG2 cells showed lower SBE-luciferase activity and lower level of active autocrine TGF-β than 4T1-Mock did. Correctly, our data show that NDRG2 significantly suppress tumor metastasis by attenuating active autocrine TGF-β production, and the attenuation might be typically associated with the favorable recurrence-free survival of patients clinically.
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Force-free field modeling of twist and braiding-induced magnetic energy in an active-region corona
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thalmann, J. K.; Tiwari, S. K.; Wiegelmann, T., E-mail: julia.thalmann@uni-graz.at
2014-01-01
The theoretical concept that braided magnetic field lines in the solar corona may dissipate a sufficient amount of energy to account for the brightening observed in the active-region (AR) corona has only recently been substantiated by high-resolution observations. From the analysis of coronal images obtained with the High Resolution Coronal Imager, first observational evidence of the braiding of magnetic field lines was reported by Cirtain et al. (hereafter CG13). We present nonlinear force-free reconstructions of the associated coronal magnetic field based on Solar Dynamics Observatory/Helioseismic and Magnetic Imager vector magnetograms. We deliver estimates of the free magnetic energy associated withmore » a braided coronal structure. Our model results suggest (∼100 times) more free energy at the braiding site than analytically estimated by CG13, strengthening the possibility of the AR corona being heated by field line braiding. We were able to appropriately assess the coronal free energy by using vector field measurements and we attribute the lower energy estimate of CG13 to the underestimated (by a factor of 10) azimuthal field strength. We also quantify the increase in the overall twist of a flare-related flux rope that was noted by CG13. From our models we find that the overall twist of the flux rope increased by about half a turn within 12 minutes. Unlike another method to which we compare our results, we evaluate the winding of the flux rope's constituent field lines around each other purely based on their modeled coronal three-dimensional field line geometry. To our knowledge, this is done for the first time here.« less
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Wu, Yongwei; He, Benzhao; Quan, Changyun; Zheng, Chao; Deng, Haiqin; Hu, Rongrong; Zhao, Zujin; Huang, Fei; Qin, Anjun; Tang, Ben Zhong
2017-09-01
The metal-free click polymerization (MFCP) of activated alkynes and azides or activated azide and alkynes have been developed into powerful techniques for the construction of polytriazoles without the obsession of metallic catalyst residues problem. However, the MFCP of activated azides and alkynes is rarely applied in preparation of functional polytriazoles. In this paper, soluble multifunctional polytriazoles (PIa and PIb) with high weight-average molecular weights (M w up to 32 000) are prepared via the developed metal-free poly-cycloaddition of activated azide and alkynes in high yields (up to 90%). The resultant PIa and PIb are thermally stable, and show aggregation-induced emission characteristics, enabling their aggregates to detect explosives with superamplification effect. Moreover, thanks to their containing aromatic rings and polar moieties, PIa and PIb exhibit high refractive indices. In addition, they can also be cross-linked upon UV irradiation to generate 2D fluorescent patterning due to their remaining azide groups and containing ester groups. Thus, these multifunctional polytriazoles are potentially applicable in the optoelectronic and sensing fields. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Zamani, Mehdi; Moradi Delfani, Ali; Jabbari, Morteza
2018-05-03
The radical scavenging performance and antioxidant activity of γ-alumina nanoparticles towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical were investigated by spectroscopic and computational methods. The radical scavenging ability of γ-alumina nanoparticles in the media with different polarity (i.e. i-propanol and n-hexane) was evaluated by measuring the DPPH absorbance in UV-Vis absorption spectra. The structure and morphology of γ-alumina nanoparticles before and after adsorption of DPPH were studied using XRD, FT-IR and UV-Vis spectroscopic techniques. The adsorption of DPPH free radical on the clean and hydrated γ-alumina (1 1 0) surface was examined by dispersion corrected density functional theory (DFT-D) and natural bond orbital (NBO) calculations. Also, time-dependent density functional theory (TD-DFT) was used to predict the absorption spectra. The adsorption was occurred through the interaction of radical nitrogen N and NO 2 groups of DPPH with the acidic and basic sites of γ-alumina surface. The high potential for the adsorption of DPPH radical on γ-alumina nanoparticles was investigated. Interaction of DPPH with Brønsted and Lewis acidic sites of γ-alumina was more favored than Brønsted basic sites. The following order for the adsorption of DPPH over the different active sites of γ-alumina was predicted: Brønsted base < Lewis acid < Brønsted acid. These results are of great significance for the environmental application of γ-alumina nanoparticles in order to remove free radicals. Copyright © 2018. Published by Elsevier B.V.
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AMCOM Hexavalent Chrome Free Initiatives
2010-12-01
AMCOM Hexavalent Chrome Free Initiatives 1 December 2010 SERDP-ESTCP Symposium Washington DC Mark Feathers AMCOM G-4 Environmental Division... Hexavalent Chrome Free Initiatives 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f...system environmental life cycle sustainability. G-4 is actively engaged in initiatives to reduce the use of hexavalent chrome used in materials and
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Lach, Marcel; Künzle, Matthias; Beck, Tobias
2017-12-11
The construction of defined nanostructured catalysts is challenging. In previous work, we established a strategy to assemble binary nanoparticle superlattices with oppositely charged protein containers as building blocks. Here, we show that these free-standing nanoparticle superlattices are catalytically active. The metal oxide nanoparticles inside the protein scaffold are accessible for a range of substrates and show oxidase-like and peroxidase-like activity. The stable superlattices can be reused for several reaction cycles. In contrast to bulk nanoparticle-based catalysts, which are prone to aggregation and difficult to characterize, nanoparticle superlattices based on engineered protein containers provide an innovative synthetic route to structurally defined heterogeneous catalysts with control over nanoparticle size and composition. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Singh, B; Saxena, A K; Chandan, B K; Gupta, D K; Bhutani, K K; Anand, K K
2001-06-01
The practitioners of the traditional Indian system of medicine regard Withania somnifera Dun. as the 'Indian ginseng'. A new withanolide-free aqueous fraction was isolated from the roots of this plant and was evaluated for putative antistress activity against a battery of tests such as hypoxia time, antifatigue effect, swimming performance time, swimming induced gastric ulceration and hypothermia, immobilization induced gastric ulceration, autoanalgesia and biochemical changes in the adrenal glands. This bioactive fraction exhibited significant antistress activity in a dose-related manner in all the parameters studied. The extract of Withania somnifera root (a commercial preparation available locally) was used to compare the results. A preliminary acute toxicity study in mice showed a good margin of safety. Copyright 2001 John Wiley & Sons, Ltd.
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Signer, Claudio; Ruf, Thomas; Schober, Franz; Fluch, Gerhard; Paumann, Thomas; Arnold, Walter
2012-01-01
Summary 1. Measuring physiological and behavioural parameters in free-ranging animals – and therefore under fully natural conditions – is of general biological concern but difficult to perform. 2. We have developed a minimally invasive telemetry system for ruminants that is capable of measuring heart rate (HR), body temperature (Tb) and locomotor activity (LA). A ruminal transmitter unit was per os placed into the reticulum and therefore located in close proximity to the heart. The unit detected HR by the use of an acceleration sensor and also measured Tb. HR and Tb signals were transmitted via short-distance UHF link to a repeater system located in a collar unit. The collar unit decoded and processed signals received from the ruminal unit, measured LA with two different activity sensors and transmitted pulse interval-modulated VHF signals over distances of up to 10 km. 3. HR data measured with the new device contained noise caused by reticulum contractions and animal movements that triggered the acceleration sensor in the ruminal unit. We have developed a software filter to remove this noise. Hence, the system was only capable of measuring HR in animals that showed little or no activity and in the absence of rumen contractions. Reliability of this ‘stationary HR’ measurement was confirmed with a second independent measurement of HR detected by an electrocardiogram in a domestic sheep (Ovis aries). 4. In addition, we developed an algorithm to correctly classify an animal as ‘active’ or ‘at rest’ during each 3-min interval from the output of the activity sensors. Comparison with direct behavioural observations on free-ranging Alpine ibex (Capra ibex) showed that 87% of intervals were classified correctly. 5. First results from applications of this new technique in free-ranging Alpine ibex underlined its suitability for reliable and long-term monitoring of physiological and behavioural parameters in ruminants under harsh field conditions. With the
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Lee, Seung Ho; Ban, Ju Yeon; Oh, Chung-Hun; Park, Hun-Kuk; Choi, Samjin
2016-06-23
We present the fabrication of an ultra-low cost, disposable, solvent-free air cathode all-paper microbial fuel cell (MFC) that does not utilize any chemical treatments. The anode and cathode were fabricated by depositing graphite particles by drawing them on paper with a pencil (four strokes). Hydrophobic parchment paper was used as a proton exchange membrane (PEM) to allow only H(+) to pass. Air cathode MFC technology, where O2 was used as an electron acceptor, was implemented on the paper platform. The bioelectric current was generated by an electrochemical process involving the redox couple of microbial-activated extracellular electron transferred electrons, PEM-passed H(+), and O2 in the cathode. A fully micro-integrated pencil-traced MFC showed a fast start-time, producing current within 10 s after injection of bacterial cells. A single miniaturized all-paper air cathode MFC generated a maximum potential of 300 mV and a maximum current of 11 μA during 100 min after a single injection of Shewanella oneidensis. The micro-fabricated solvent-free air cathode all-paper MFC generated a power of 2,270 nW (5.68 mW/m(2)). The proposed solvent-free air cathode paper-based MFC device could be used for environmentally-friendly energy storage as well as in single-use medical power supplies that use organic matter.
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Lee, Seung Ho; Ban, Ju Yeon; Oh, Chung-Hun; Park, Hun-Kuk; Choi, Samjin
2016-01-01
We present the fabrication of an ultra-low cost, disposable, solvent-free air cathode all-paper microbial fuel cell (MFC) that does not utilize any chemical treatments. The anode and cathode were fabricated by depositing graphite particles by drawing them on paper with a pencil (four strokes). Hydrophobic parchment paper was used as a proton exchange membrane (PEM) to allow only H+ to pass. Air cathode MFC technology, where O2 was used as an electron acceptor, was implemented on the paper platform. The bioelectric current was generated by an electrochemical process involving the redox couple of microbial-activated extracellular electron transferred electrons, PEM-passed H+, and O2 in the cathode. A fully micro-integrated pencil-traced MFC showed a fast start-time, producing current within 10 s after injection of bacterial cells. A single miniaturized all-paper air cathode MFC generated a maximum potential of 300 mV and a maximum current of 11 μA during 100 min after a single injection of Shewanella oneidensis. The micro-fabricated solvent-free air cathode all-paper MFC generated a power of 2,270 nW (5.68 mW/m2). The proposed solvent-free air cathode paper-based MFC device could be used for environmentally-friendly energy storage as well as in single-use medical power supplies that use organic matter. PMID:27333815
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NASA Astrophysics Data System (ADS)
Lee, Seung Ho; Ban, Ju Yeon; Oh, Chung-Hun; Park, Hun-Kuk; Choi, Samjin
2016-06-01
We present the fabrication of an ultra-low cost, disposable, solvent-free air cathode all-paper microbial fuel cell (MFC) that does not utilize any chemical treatments. The anode and cathode were fabricated by depositing graphite particles by drawing them on paper with a pencil (four strokes). Hydrophobic parchment paper was used as a proton exchange membrane (PEM) to allow only H+ to pass. Air cathode MFC technology, where O2 was used as an electron acceptor, was implemented on the paper platform. The bioelectric current was generated by an electrochemical process involving the redox couple of microbial-activated extracellular electron transferred electrons, PEM-passed H+, and O2 in the cathode. A fully micro-integrated pencil-traced MFC showed a fast start-time, producing current within 10 s after injection of bacterial cells. A single miniaturized all-paper air cathode MFC generated a maximum potential of 300 mV and a maximum current of 11 μA during 100 min after a single injection of Shewanella oneidensis. The micro-fabricated solvent-free air cathode all-paper MFC generated a power of 2,270 nW (5.68 mW/m2). The proposed solvent-free air cathode paper-based MFC device could be used for environmentally-friendly energy storage as well as in single-use medical power supplies that use organic matter.
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NASA Technical Reports Server (NTRS)
Falconer, David; Moore, Ron
2011-01-01
For mature active regions, an active region s magnetic flux content determines the maximum free energy the active region can have. Most Large flares and CMEs occur in active regions that are near their free-energy limit. Active-region flare power radiated in the GOES 1-8 band increases steeply as the free-energy limit is approached. We infer that the free-energy limit is set by the rate of release of an active region s free magnetic energy by flares, CMEs and coronal heating balancing the maximum rate the Sun can put free energy into the active region s magnetic field. This balance of maximum power results in explosive active regions residing in a "mainsequence" in active-region (flux content, free energy content) phase space, which sequence is analogous to the main sequence of hydrogen-burning stars in (mass, luminosity) phase space.
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Suseem, S R; Saral, Mary
2015-07-01
To evaluate the ethyl acetate, methanol and aqueous extracts of dried fruiting bodies of Pleurotus eous for its anti-platelet activity on human volunteer's blood. And also to analyze the free radical scavenging property of the extracts of P.eous by using various in vitro models. Anti-platelet activity of dried fruiting bodies of P.eous was evaluated by in vitro model using blood platelets. Inhibition of platelet aggregation was monitored after pre-incubation of platelets with the crude extracts of mushroom P.eous. Antioxidant activities of extracts of P.eous were evaluated by different in vitro experiments, namely, 1, 1-diphenyl-2-picryl hydrazyl (DPPH), superoxide, hydroxyl radical and lipid peroxide radical models. Crude extracts of mushroom P.eous inhibited platelet aggregation dose-dependently which was induced by adenosine diphosphate (ADP). At a maximum concentration of 10 mg/mL, methanol extract effected 64.02% inhibition of lipid per-oxidation and 50.12% scavenging effect on superoxide anion radical. Aqueous extract of P.eous have shown 69.43% chelating ability on ferrous ions, 24.27% scavenging effect on hydroxyl radical and 49.57% scavenging effect on DPPH radical at 10 mg/mL. Increasing concentrations of the extract were found to cause progressively decreasing of the intensity of absorbance. Anti-platelet effects could be related in part to the polyphenolic compounds present in the extracts. Antioxidant activity results indicated the free radical scavenging property of the extracts of P.eous which might be due to the high content of phenolic compounds and flavonoids.
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NASA Astrophysics Data System (ADS)
Dauthal, Preeti; Mukhopadhyay, Mausumi
2013-01-01
In-vitro free radical scavenging activity of biosynthesized gold (Au-NPs) and silver (Ag-NPs) nanoparticles was investigated in the present study. Natural precursor Prunus armeniaca (apricot) fruit extract was used as a reducing agent for the nanoparticle synthesis. The free radical scavenging activity of the nanoparticles were observed by modified 1,1'-diphynyl-2-picrylhydrazyl, DPPH and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid), ABTS assay. The synthesized nanoparticles were characterized by UV-Visible spectroscopy, dynamic light scattering, transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive spectroscopy, and fourier transform infrared spectroscopy (FTIR). Appearance of optical absorption peak at 537 nm (2.20 keV) and 435 nm (3 keV) within 0.08 and 0.5 h of reaction time was confirmed the presence of metallic Au and Ag nanoclusters, respectively. Nearly spherical nanoparticles with majority of particle below 20 nm (TEM) for both Au-NPs and Ag-NPs were synthesized. XRD pattern confirmed the existence of pure nanocrystalline Au-NPs while few additional peaks in the vicinity of fcc silver-speculated crystallization of metalloproteins of fruit extract on the surface of the Ag-NPs and vice versa. FTIR spectra was supported the role of amino acids of protein/enzymes of fruit extract for synthesis and stabilization of nanoparticles. Dose-dependent scavenging activity was observed for Au-NPs and Ag-NPs in both DPPH and ABTS in-vitro assay. 50 % scavenging activity for DPPH were 11.27 and 16.18 mg and for ABTS 3.40 and 7.12 mg with Au-NPs and Ag-NPs, respectively.
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ERIC Educational Resources Information Center
Varela Mato, Veronica; Yates, Thomas; Stensel, David; Biddle, Stuart; Clemes, Stacy A.
2017-01-01
This study explored the validity of ActiGraph-determined sedentary time (<50 cpm, <100 cpm, <150 cpm, <200 cpm, <250 cpm) compared with the activPAL in a free-living sample of bus drivers. Twenty-eight participants were recruited between November 2013 and February 2014. Participants wore an activPAL3 and ActiGraph GT3X+ concurrently…
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Wei, Fu-Chan; Mardini, Samir
2004-09-15
Free-tissue transfer has become the accepted standard for reconstruction of complex defects. With the growth of this field, anatomic studies and clinical work have added many flaps to the armamentarium of the microvascular surgeon. Further advancements and experience with techniques of perforator flap surgery have allowed for the harvest of flaps in a free-style manner, where a flap is harvested based only on the preoperative knowledge of Doppler signals present in a specific region. Between June of 2002 and September of 2003, 13 free-style free flaps were harvested from the region of the thigh. All patients presented with an oral or pharyngeal cancer and underwent resection and immediate reconstruction of these flaps. All flaps were cutaneous and were harvested in a suprafascial plane. The average size of the flaps was 108 cm2 (range, 36 to 187 cm2), and the average length of the vascular pedicle was 10 cm (range, 9 to 12 cm). All flaps were successful in achieving wound coverage and functional outcomes without any vascular compromise necessitating re-exploration. Free-style free flaps have become a clinical reality. The concepts and techniques used to harvest a free-style free flap will aid in dealing with anatomic variations that are encountered during conventional flap harvest. Future trends in flap selection will focus mainly on choosing tissue with appropriate texture, thickness, and pliability to match requirements at the recipient site while minimizing donor-site morbidity.
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Demi-embryo production from hatching of zona-drilled bovine and rabbit blastocysts.
Skrzyszowska, M; Smorag, Z; Katska, L
1997-09-01
It is known that the pregnancy rate resulting after transfer of bisected embryos is lower than after transfer of whole embryos. The main reason is the reduced cell number in the demi-embryo which is less than 1 2 of that in the intact embryo, since a number of blastomeres is damaged as a result of the procedure used in conventional embryo splitting. The aim of our experiment was to develop a non-invasive procedure which would limit cell losses during microsurgery. The experiment was carried out on bovine IVM-IVF embryos at middle, late and expanded blastocyst stage and rabbit embryos at late blastocyst stage cultured in vitro from in vivo produced zygotes. The zona pellucida of these embryos was drilled on the line between the inner cell mass and the trophoblast using a glass microneedle (
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Ferguson, Ty; Rowlands, Alex V; Olds, Tim; Maher, Carol
2015-03-27
Technological advances have seen a burgeoning industry for accelerometer-based wearable activity monitors targeted at the consumer market. The purpose of this study was to determine the convergent validity of a selection of consumer-level accelerometer-based activity monitors. 21 healthy adults wore seven consumer-level activity monitors (Fitbit One, Fitbit Zip, Jawbone UP, Misfit Shine, Nike Fuelband, Striiv Smart Pedometer and Withings Pulse) and two research-grade accelerometers/multi-sensor devices (BodyMedia SenseWear, and ActiGraph GT3X+) for 48-hours. Participants went about their daily life in free-living conditions during data collection. The validity of the consumer-level activity monitors relative to the research devices for step count, moderate to vigorous physical activity (MVPA), sleep and total daily energy expenditure (TDEE) was quantified using Bland-Altman analysis, median absolute difference and Pearson's correlation. All consumer-level activity monitors correlated strongly (r > 0.8) with research-grade devices for step count and sleep time, but only moderately-to-strongly for TDEE (r = 0.74-0.81) and MVPA (r = 0.52-0.91). Median absolute differences were generally modest for sleep and steps (<10% of research device mean values for the majority of devices) moderate for TDEE (<30% of research device mean values), and large for MVPA (26-298%). Across the constructs examined, the Fitbit One, Fitbit Zip and Withings Pulse performed most strongly. In free-living conditions, the consumer-level activity monitors showed strong validity for the measurement of steps and sleep duration, and moderate valid for measurement of TDEE and MVPA. Validity for each construct ranged widely between devices, with the Fitbit One, Fitbit Zip and Withings Pulse being the strongest performers.
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Benavides Valades, Gabriela; Ganswindt, Andre; Annandale, Henry; Schulman, Martin L; Bertschinger, Henk J
2012-08-25
In southern Africa, various options to manage elephant populations are being considered. Immunocontraception is considered to be the most ethically acceptable and logistically feasible method for control of smaller and confined populations. In this regard, the use of gonadotropin-releasing hormone (GnRH) vaccine has not been investigated in female elephants, although it has been reported to be safe and effective in several domestic and wildlife species. The aims of this study were to monitor the oestrous cycles of free-ranging African elephant cows using faecal progestagen metabolites and to evaluate the efficacy of a GnRH vaccine to induce anoestrus in treated cows. Between May 2009-June 2010, luteal activity of 12 elephant cows was monitored non-invasively using an enzyme immunoassay detecting faecal 5alpha-reduced pregnanes (faecal progestagen metabolites, FPM) on a private game reserve in South Africa. No bulls of breeding age were present on the reserve prior to and for the duration of the study. After a 3-month control period, 8 randomly-selected females were treated twice with 600 micrograms of GnRH vaccine (Improvac®, Pfizer Animal Health, Sandton, South Africa) 5-7 weeks apart. Four of these females had been treated previously with the porcine zona pellucida (pZP) vaccine for four years (2004-2007). All 12 monitored females (8 treated and 4 controls) showed signs of luteal activity as evidenced by FPM concentrations exceeding individual baseline values more than once. A total of 16 oestrous cycles could be identified in 8 cows with four of these within the 13 to 17 weeks range previously reported for captive African elephants. According to the FPM concentrations the GnRH vaccine was unable to induce anoestrus in the treated cows. Overall FPM levels in samples collected during the wet season (mean 4.03 micrograms/gram dry faeces) were significantly higher (P<0.002) than the dry season (mean 2.59 micrograms/gram dry faeces). The GnRH vaccination protocol
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Fajer, Mikolai; Meng, Yilin; Roux, Benoît
2017-04-20
Tyrosine kinases are important cellular signaling allosteric enzymes that regulate cell growth, proliferation, metabolism, differentiation, and migration. Their activity must be tightly controlled, and malfunction can lead to a variety of diseases, particularly cancer. The nonreceptor tyrosine kinase c-Src, a prototypical model system and a representative member of the Src-family, functions as complex multidomain allosteric molecular switches comprising SH2 and SH3 domains modulating the activity of the catalytic domain. The broad picture of self-inhibition of c-Src via the SH2 and SH3 regulatory domains is well characterized from a structural point of view, but a detailed molecular mechanism understanding is nonetheless still lacking. Here, we use advanced computational methods based on all-atom molecular dynamics simulations with explicit solvent to advance our understanding of kinase activation. To elucidate the mechanism of regulation and self-inhibition, we have computed the pathway and the free energy landscapes for the "inactive-to-active" conformational transition of c-Src for different configurations of the SH2 and SH3 domains. Using the isolated c-Src catalytic domain as a baseline for comparison, it is observed that the SH2 and SH3 domains, depending upon their bound orientation, promote either the inactive or active state of the catalytic domain. The regulatory structural information from the SH2-SH3 tandem is allosterically transmitted via the N-terminal linker of the catalytic domain. Analysis of the conformational transition pathways also illustrates the importance of the conserved tryptophan 260 in activating c-Src, and reveals a series of concerted events during the activation process.
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Flexible integration of free-standing nanowires into silicon photonics.
Chen, Bigeng; Wu, Hao; Xin, Chenguang; Dai, Daoxin; Tong, Limin
2017-06-14
Silicon photonics has been developed successfully with a top-down fabrication technique to enable large-scale photonic integrated circuits with high reproducibility, but is limited intrinsically by the material capability for active or nonlinear applications. On the other hand, free-standing nanowires synthesized via a bottom-up growth present great material diversity and structural uniformity, but precisely assembling free-standing nanowires for on-demand photonic functionality remains a great challenge. Here we report hybrid integration of free-standing nanowires into silicon photonics with high flexibility by coupling free-standing nanowires onto target silicon waveguides that are simultaneously used for precise positioning. Coupling efficiency between a free-standing nanowire and a silicon waveguide is up to ~97% in the telecommunication band. A hybrid nonlinear-free-standing nanowires-silicon waveguides Mach-Zehnder interferometer and a racetrack resonator for significantly enhanced optical modulation are experimentally demonstrated, as well as hybrid active-free-standing nanowires-silicon waveguides circuits for light generation. These results suggest an alternative approach to flexible multifunctional on-chip nanophotonic devices.Precisely assembling free-standing nanowires for on-demand photonic functionality remains a challenge. Here, Chen et al. integrate free-standing nanowires into silicon waveguides and show all-optical modulation and light generation on silicon photonic chips.
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Smoke-free legislation and charitable gaming in Kentucky.
Pyles, M K; Hahn, E J
2009-02-01
To determine the effect of municipal smoke-free laws in Kentucky on gross and/or net revenues from charitable gaming activities. Between January 2000 and June 2007, 13 Kentucky communities implemented smoke-free legislation; only three specifically exempted charitable gaming facilities and compliance in several communities was not consistent. Kentucky is a tobacco-growing state that has the highest smoking rate in the United States. A fixed-effects time series design to estimate the impact of municipal smoke-free laws on charitable gaming. 13 Kentucky counties that implemented smoke-free laws during the study period of January 2000 through June 2007. All charitable gaming facilities in 13 counties in which a smoke-free ordinance was enacted during the study period. Gross and net revenues from charitable gaming activities in each county for each quarter of the study period, obtained from the Kentucky Department of Charitable Gaming. When controlling for economic variables, county-specific effects and time trends using a robust statistical framework, there was no significant relation between smoke-free laws and charitable gaming revenues. Municipal smoke-free legislation had no effect on charitable gaming revenues. No significant harm to charitable gaming revenues was associated with the smoke-free legislation during the 7.5-year study period, despite the fact that Kentucky is a tobacco-producing state with higher-than-average smoking rates.
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Terio, Karen A; Marker, Laurie; Munson, Linda
2004-04-01
The cheetah (Acinonyx jubatus) is highly endangered because of loss of habitat in the wild and failure to thrive in captivity. Cheetahs in zoos reproduce poorly and have high prevalences of unusual diseases that cause morbidity and mortality. These diseases are rarely observed in free-ranging cheetahs but have been documented in cheetahs that have been captured and held in captive settings either temporarily or permanently. Because captivity may be stressful for this species and stress is suspected as contributing to poor health and reproduction, this study aimed to measure chronic stress by comparing baseline concentrations of fecal corticoid metabolites and adrenal gland morphology between captive and free-ranging cheetahs. Additionally, concentrations of estradiol and testosterone metabolites were quantified to determine whether concentrations of gonadal steroids correlated with corticoid concentration and to assure that corticosteroids in the free-ranging samples were not altered by environmental conditions. Concetntrations of fecal corticoids, estradiol, and testosterone were quantified by radioimmunoassay in 20 free-ranging and 20 captive cheetahs from samples collected between 1994 and 1999. Concentrations of baseline fecal corticoids were significantly higher (p = 0.005) in captive cheetahs (196.08 +/- 36.20 ng/g dry feces) than free-ranging cheetahs (71.40 +/- 14.35 ng/g dry feces). Testosterone concentrations were lower in captive male cheetahs (9.09 +/- 2.84 ng/g dry feces) than in free-ranging cheetahs (34.52 +/- 12.11 ng/g dry feces), which suggests suppression by elevated corticoids in the captive males. Evidence for similar sulppression of estradiol concentrations in females was not present. Adrenal corticomedullary ratios were determined on midsagittal sections of adrenal glands from 13 free-ranging and 13 captive cheetahs obtained between 1991 and 2002. The degree of vacuolation of cortical cells in the zona fasciculata was graded for each animal
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Löf, Marie; Henriksson, Hanna; Forsum, Elisabet
2013-01-01
Activity energy expenditure (AEE) during free-living conditions can be assessed using devices based on different principles. To make proper comparisons of different devices' capacities to assess AEE, they should be evaluated in the same population. Thus, in the present study we evaluated, in the same group of subjects, the ability of three devices to assess AEE in groups and individuals during free-living conditions. In twenty women, AEE was assessed using RT3 (three-axial accelerometry) (AEERT3), Actiheart (a combination of heart rate and accelerometry) (AEEActi) and IDEEA (a multi-accelerometer system) (AEEIDEEA). Reference AEE (AEEref) was assessed using the doubly labelled water method and indirect calorimetry. Average AEEActi was 5760 kJ per 24 h and not significantly different from AEEref (5020 kJ per 24 h). On average, AEERT3 and AEEIDEEA were 2010 and 1750 kJ per 24 h lower than AEEref, respectively (P < 0·001). The limits of agreement (± 2 sd) were 2940 (Actiheart), 1820 (RT3) and 2650 (IDEEA) kJ per 24 h. The variance for AEERT3 was lower than for AEEActi (P = 0·006). The RT3 classified 60 % of the women in the correct activity category while the corresponding value for IDEEA and Actiheart was 30 %. In conclusion, the Actiheart may be useful for groups and the RT3 for individuals while the IDEEA requires further development. The results are likely to be relevant for a large proportion of Western women of reproductive age and demonstrate that the procedure selected to assess physical activity can greatly influence the possibilities to uncover important aspects regarding interactions between physical activity, diet and health.
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Maurer, Manuela; de Beer, Stephanie B. A.; Oostenbrink, Chris
2018-01-01
The periplasmic oligopeptide binding protein A (OppA) represents a well-known example of water-mediated protein-ligand interactions. Here, we perform free-energy calculations for three different ligands binding to OppA, using a thermodynamic integration approach. The tripeptide ligands share a high structural similarity (all have the sequence KXK), but their experimentally-determined binding free energies differ remarkably. Thermodynamic cycles were constructed for the ligands, and simulations conducted in the bound and (freely solvated) unbound states. In the unbound state, it was observed that the difference in conformational freedom between alanine and glycine leads to a surprisingly slow convergence, despite their chemical similarity. This could be overcome by increasing the softness parameter during alchemical transformations. Discrepancies remained in the bound state however, when comparing independent simulations of the three ligands. These difficulties could be traced to a slow relaxation of the water network within the active site. Fluctuations in the number of water molecules residing in the binding cavity occur mostly on a timescale larger than the simulation time along the alchemical path. After extensive simulations, relative binding free energies that were converged to within thermal noise could be obtained, which agree well with available experimental data. PMID:27092480
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7 CFR 15b.22 - Free appropriate public education.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 1 2011-01-01 2011-01-01 false Free appropriate public education. 15b.22 Section 15b... Extension Education § 15b.22 Free appropriate public education. (a) General. A recipient that operates a public elementary or secondary education program or activity shall provide a free appropriate public...
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7 CFR 15b.22 - Free appropriate public education.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 1 2014-01-01 2014-01-01 false Free appropriate public education. 15b.22 Section 15b... Extension Education § 15b.22 Free appropriate public education. (a) General. A recipient that operates a public elementary or secondary education program or activity shall provide a free appropriate public...
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7 CFR 15b.22 - Free appropriate public education.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 7 Agriculture 1 2012-01-01 2012-01-01 false Free appropriate public education. 15b.22 Section 15b... Extension Education § 15b.22 Free appropriate public education. (a) General. A recipient that operates a public elementary or secondary education program or activity shall provide a free appropriate public...
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7 CFR 15b.22 - Free appropriate public education.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 7 Agriculture 1 2013-01-01 2013-01-01 false Free appropriate public education. 15b.22 Section 15b... Extension Education § 15b.22 Free appropriate public education. (a) General. A recipient that operates a public elementary or secondary education program or activity shall provide a free appropriate public...
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7 CFR 15b.22 - Free appropriate public education.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 1 2010-01-01 2010-01-01 false Free appropriate public education. 15b.22 Section 15b... Extension Education § 15b.22 Free appropriate public education. (a) General. A recipient that operates a public elementary or secondary education program or activity shall provide a free appropriate public...
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Tang, Kit Tzu; Richardson, Alison M; Maxwell, Douglas; Spence, William D; Stansfield, Benedict W
2013-12-01
To explore the use of an activity monitor (AM) to objectively characterize free-living physical activity (F-LPA) in children with mobility impairment resulting from cerebral palsy (CP). First, a validation study compared outcomes from the AM with video evidence. Second, multiday F-LPA was characterized. Relationships between laboratory measures and F-LPA were explored. The evaluation study was conducted in a laboratory environment. F-LPA monitoring was conducted in the participants' free-living environment. Convenience sample of ambulatory children (N=15; 11 boys, 4 girls) aged 5 to 17 years with CP undergoing gait analysis. Not applicable. Accuracy of the AM for sitting/lying time, upright time, stepping time, and strides taken. Daily volumes of F-LPA of children with CP. AM outcomes in comparison with video-based analysis were (mean ± SD) 97.4%±2.7%, 101.1%±1.5%, 99.5%±6.6%, 105.6%±15.8%, and 103.8%±10.1% for sitting/lying time, upright time, standing time, stepping time, and stride count, respectively. Participants' daily F-LPA demonstrated considerable variation: mean standing time ± SD, 2.33±.96h/d; mean stepping time ± SD, 1.68±.86h/d; mean steps per day ± SD, 8477±4528; and mean sit-to-stand transitions per day ± SD, 76±49. Laboratory-measured cadence and mobility level were related to F-LPA, but not directly. The AM demonstrated excellent ability to determine sitting/lying and upright times in children with CP. Stepping time and stride count had lower levels of agreement with video-based analysis but were comparable to findings in previous studies. Crouch gait and toe walking had an adverse effect on outcomes. The F-LPA data provided additional information on children's performance not related to laboratory measures, demonstrating the added value of using this objective measurement technique. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
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Orexin Gene Transfer into Zona Incerta Neurons Suppresses Muscle Paralysis in Narcoleptic Mice
Liu, Meng; Konadhode, RodaRani; Begum, Suraiya; Pelluru, Dheeraj; Gerashchenko, Dmitry; Sakurai, Takeshi; Yanagisawa, Masashi; van den Pol, Anthony N.
2011-01-01
Cataplexy, a sudden unexpected muscle paralysis, is a debilitating symptom of the neurodegenerative sleep disorder, narcolepsy. During these attacks, the person is paralyzed, but fully conscious and aware of their surroundings. To identify potential neurons that might serve as surrogate orexin neurons to suppress such attacks, the gene for orexin (hypocretin), a peptide lost in most human narcoleptics, was delivered into the brains of the orexin-ataxin-3 transgenic mouse model of human narcolepsy. Three weeks after the recombinant adenoassociated virus (rAAV)-mediated orexin gene transfer, sleep–wake behavior was assessed. rAAV-orexin gene delivery into neurons of the zona incerta (ZI), or the lateral hypothalamus (LH) blocked cataplexy. Orexin gene transfer into the striatum or in the melanin-concentrating hormone neurons in the ZI or LH had no such effect, indicating site specificity. In transgenic mice lacking orexin neurons but given rAAV-orexin, detectable levels of orexin-A were evident in the CSF, indicating release of the peptide from the surrogate neurons. Retrograde tracer studies showed that the amygdala innervates the ZI consistent with evidence that strong emotions trigger cataplexy. In turn, the ZI projects to the locus ceruleus, indicating that the ZI is part of a circuit that stabilizes motor tone. Our results indicate that these neurons might also be recruited to block the muscle paralysis in narcolepsy. PMID:21508228
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75 FR 54352 - Agency Information Collection Activities: Free Trade Agreements
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-07
... collection: Chile, Singapore, Australia, Morocco, Bahrain, Jordan, Oman, and Peru. These agreements involve... addition of free trade agreements with Oman and Peru. Type of Review: Extension (with change). Affected...
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Amygdala activity at encoding correlated with long-term, free recall of emotional information.
Cahill, L; Haier, R J; Fallon, J; Alkire, M T; Tang, C; Keator, D; Wu, J; McGaugh, J L
1996-07-23
Positron emission tomography of cerebral glucose metabolism in adult human subjects was used to investigate amygdaloid complex (AC) activity associated with the storage of long-term memory for emotionally arousing events. Subjects viewed two videos (one in each of two separate positron emission tomography sessions, separated by 3-7 days) consisting either of 12 emotionally arousing film clips ("E" film session) or of 12 relatively emotionally neutral film clips ("N" film session), and rated their emotional reaction to each film clip immediately after viewing it. Three weeks after the second session, memory for the videos was assessed in a free recall test. As expected, the subjects' average emotional reaction to the E films was higher than that for the N films. In addition, the subjects recalled significantly more E films than N films. Glucose metabolic rate of the right AC while viewing the E films was highly correlated with the number of E films recalled. AC activity was not significantly correlated with the number of N films recalled. The findings support the view derived from both animal and human investigations that the AC is selectively involved with the formation of enhanced long-term memory associated with emotionally arousing events.
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Piezoelectric Active Humidity Sensors Based on Lead-Free NaNbO₃ Piezoelectric Nanofibers.
Gu, Li; Zhou, Di; Cao, Jun Cheng
2016-06-07
The development of micro-/nano-scaled energy harvesters and the self-powered sensor system has attracted great attention due to the miniaturization and integration of the micro-device. In this work, lead-free NaNbO₃ piezoelectric nanofibers with a monoclinic perovskite structure were synthesized by the far-field electrospinning method. The flexible active humidity sensors were fabricated by transferring the nanofibers from silicon to a soft polymer substrate. The sensors exhibited outstanding piezoelectric energy-harvesting performance with output voltage up to 2 V during the vibration process. The output voltage generated by the NaNbO₃ sensors exhibited a negative correlation with the environmental humidity varying from 5% to 80%, where the peak-to-peak value of the output voltage generated by the sensors decreased from 0.40 to 0.07 V. The sensor also exhibited a short response time, good selectively against ethanol steam, and great temperature stability. The piezoelectric active humidity sensing property could be attributed to the increased leakage current in the NaNbO₃ nanofibers, which was generated due to proton hopping among the H₃O⁺ groups in the absorbed H₂O layers under the driving force of the piezoelectric potential.
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Powell, Joshua; Luh, Jeanne; Coronell, Orlando
2015-10-20
The volume-averaged amide link scission in the aromatic polyamide active layer of a reverse osmosis membrane upon exposure to free chlorine was quantified at a variety of free chlorine exposure times, concentrations, and pH and rinsing conditions. The results showed that (i) hydroxyl ions are needed for scission to occur, (ii) hydroxide-induced amide link scission is a strong function of exposure to hypochlorous acid, (iii) the ratio between amide links broken and chlorine atoms taken up increased with the chlorination pH and reached a maximum of ∼25%, (iv) polyamide disintegration occurs when high free chlorine concentrations, alkaline conditions, and high exposure times are combined, (v) amide link scission promotes further chlorine uptake, and (vi) scission at the membrane surface is unrepresentative of volume-averaged scission in the active layer. Our observations are consistent with previously proposed mechanisms describing amide link scission as a result of the hydrolysis of the N-chlorinated amidic N-C bond due to nucleophilic attack by hydroxyl ions. This study increases the understanding of the physicochemical changes that could occur for membranes in treatment plants using chlorine as an upstream disinfectant and the extent and rate at which those changes would occur.
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Dodt, Johannes; Pasternack, Ralf; Seitz, Rainer; Volkers, Peter
2016-02-01
In a factor XIIIa (FXIIIa) generation assay with recombinant FXIII-A2 (rFXIII-A2 ) free FXIII activation peptide (fAP-FXII) prolonged the time to peak (TTP) but did not affect the area under the curve (AUC) or concentration at peak (CP). Addition of recombinant factorXIII-B2 (rFXIII-B2 ) restored the characteristics of the FXIIIa generation parameters (AUC, TTP and CP) to those observed for plasma FXIII (FXIII-A2 B2 ). FXIII-A2 B2 reconstituted from rFXIII-A2 and rFXIII-B2 showed a similar effect on AUC, TTP and CP in the presence of fAP-FXII as observed for plasma FXIII-A2 B2 , indicating a role for FXIII-B in this observation. An effect of fAP-FXIII on thrombin, the proteolytic activator of FXIII, was excluded by thrombin generation assays and clotting experiments. In a purified system, fAP-FXIII did not interfere with the FXIIIa activity development of thrombin-cleaved rFXIII-A2 (rFXIII-A2 ') also excluding direct inhibition of FXIIIa. However, FXIIIa activity development of FXIII-A2 'B2 was inhibited in a concentration-dependent manner by fAP-FXIII, indicating that an interaction between AP-FXIII and FXIII-B2 contributes to the overall stability of FXIII-A2 'B2 . In addition to its well-known role, FXIII-B also contributes to FXIII-A2 B2 stability or dissociation depending on fAP-FXIII and calcium concentrations. © 2015 John Wiley & Sons Ltd.
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Sun, Liping; Zhang, Huilin; Zhuang, Yongliang
2012-02-01
The soluble phenolic compounds of rambutan peels (RP) were extracted by microwave-assisted extraction (MAE) and the operating parameters were optimized. The optimal conditions obtained were ethanol concentration of 80.85%, extraction time of 58.39 s, and the ratio of liquid to solid of 24.51:1. The soluble phenolic content by MAE was 213.76 mg GAE/g DW. The free, soluble conjugate, and insoluble-boaund phenolic compounds were prepared by alkaline hydrolysis, and the contents of 3 fractions were 185.12, 27.98 and 9.37 mg GAE/g DW, respectively. The contents of syringic acid and p-coumaric acid were high in the free fraction, showing 16.86 and 19.44 mg/g DW, and the soluble conjugate and insoluble-bound phenolics were mainly composed of gallic acid and caffeic acid. Furthermore, the antioxidant activities of 3 fractions were evaluated in 5 model systems. Results indicated that the free fraction had high antioxidant activities, compared with the soluble conjugate and insoluble-bound fractions. © 2012 Institute of Food Technologists®
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Hamed, Said Fatouh; Sadek, Zainab; Edris, Amr
2012-01-01
Clove bud essential oil (CEO) and its major individual phenolic constituent eugenol were formulated as nanoparticles in water-based microemulsion systems. The oil titration method was used to incorporate different amounts of the oil and eugenol in the micellar solution of Tween-20. The Antioxidant and antimicrobial activities were evaluated using the DPPH* free radical scavenging assay and the agar disc dilution method, respectively. Results showed that microemulsion improved the evaluated activities of CEO and eugenol compared with the crude counterparts. Individual eugenol microemulsion was more effective than CEO microemulsion which contained only 61.7% eugenol among its constituents. The results of this study could have potential applications in water-based disinfectants, preservation and flavoring of food and in personal hygiene products. It may also have promising applications in the nutraceutical and functional beverage field.
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Zhang, Jinfeng; Chen, Wencheng; Chen, Rui; Liu, Xiao-Ke; Xiong, Yuan; Kershaw, Stephen V; Rogach, Andrey L; Adachi, Chihaya; Zhang, Xiaohong; Lee, Chun-Sing
2016-09-27
We applied organic nanostructures based on thermally activated delayed fluorescent (TADF) emitters for singlet oxygen generation. Due to the extremely small energy gaps between the excited singlet states (S 1 ) and triplet states (T 1 ) of these heavy-metal-free organic nanostructures, intersystem conversion between S 1 and T 1 can occur easily. This strategy also works well for exciplex-type TADF emitters prepared by mixing suitable donors and acceptors which have no TADF characteristics themselves.
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75 FR 68808 - Agency Information Collection Activities: Free Trade Agreements
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-09
... information collection: Chile, Singapore, Australia, Morocco, Bahrain, Jordan, Oman, and Peru. These... hours based on the addition of free trade agreements with Oman and Peru. Type of Review: Extension (with...
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Cryopreservation for bovine embryos in serum-free freezing medium containing silk protein sericin.
Isobe, Tomohiro; Ikebata, Yoshihisa; Onitsuka, Takeshi; Do, Lanh Thi Kim; Sato, Yoko; Taniguchi, Masayasu; Otoi, Takeshige
2013-10-01
Because the use of serum in the embryo cryopreservation increases the probability of animal health problems such as bovine spongiform encephalopathy (BSE) and viral infections, this study was conducted to examine the effects of sericin supplementation for serum-free freezing medium on the survival and development of bovine embryos after freezing-thawing and direct transfer to recipients. When in vitro-produced bovine embryos were frozen conventionally in the freezing medium supplemented with various concentrations (0.1%, 0.5%, and 1.0%) of sericin, the percentages of damaged zona pellucida, survival, and development of frozen-thawed embryos were similar to those of embryos frozen in freezing medium supplemented with 0.4% bovine serum albumin (BSA) and 20% fetal bovine serum (FBS) (0.4BSA/20F; control). When in vivo-derived embryos were frozen with 0.4BSA/20F (control), 0.5% sericin +20% FBS (0.5S/20F) or 0.5% sericin (0.5S) and were subsequently transferred directly to recipients, the percentages of recipients with pregnancy and normal calving in the 0.5S/20F group were higher than those in the control group (47.3% vs. 40.1% and 94.6% vs. 87.3%, respectively). Moreover, the percentages of recipients with pregnancy and normal calving (42.2% and 92.4%, respectively) in the 0.5S group were similar with those of other groups. In conclusion, these results indicate that serum-free freezing medium supplemented with sericin is available for the cryopreservation of bovine embryos and that it is beneficial for the elimination of a potential source of biological contamination by serum or BSA. Copyright © 2013. Published by Elsevier Inc.
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Zhang, Ying; Wu, Xiao-qing; Yu, Zuo-yu
2002-04-01
To investigate the differences of total flavonoid (TF) content and antifree radical activity between the-leaves of bamboo and Gingo biloba, as well as their seasonal changes. Spectrophotometery and Chemiluminescence methods were adopted to determine TF and half inhibiting concentration (IC50) on active oxygen free radicals of the leaves of bamboo, phyllostachys nigra (Lodd. ex. Lindl.) Munro, and Ginkgo biloba. Two kinds of leaves were picked in the same plot at the same time monthly. The TF of bamboo leaf varied in the range of 0.67%-1.71% (in dry basis of leaf, below as same) throughout a year, the minimum apparing in June and the maximum in July, then going down obviously, and remaining at a much high lever during November to next April. However, the TF of Ginkgo bilabo leaf varied in 1.48%-2.49% during whole growing period, early April to late November. It ascended with the growth of leaf, reaching the top during June and July, the going down slowly, and finally another peak appeared before defoliation. The average IC50 values on O2-. and .OH of bamboo leaf were at 11.0 micrograms.mL-1 and 5.3 mg.mL-1, and Ginkgo biloba at 19.0 micrograms.mL-1 and 3.6 mg.mL-1, respectively. The TF content and anti-free radical activity the bamboo leaf are comparable with the leaf of ginkgo biloba, which is a kind of potential resources for natural antioxidant and free radical scavenger.
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Diestel, Uschi; Resch, Marcus; Meinhardt, Kathrin; Weiler, Sigrid; Hellmann, Tina V.; Mueller, Thomas D.; Nickel, Joachim; Eichler, Jutta; Muller, Yves A.
2013-01-01
The zona pellucida (ZP) domain is present in extracellular proteins such as the zona pellucida proteins and tectorins and participates in the formation of polymeric protein networks. However, the ZP domain also occurs in the cytokine signaling co-receptor transforming growth factor β (TGF-β) receptor type 3 (TGFR-3, also known as betaglycan) where it contributes to cytokine ligand recognition. Currently it is unclear how the ZP domain architecture enables this dual functionality. Here, we identify a novel major TGF-β-binding site in the FG loop of the C-terminal subdomain of the murine TGFR-3 ZP domain (ZP-C) using protein crystallography, limited proteolysis experiments, surface plasmon resonance measurements and synthetic peptides. In the murine 2.7 Å crystal structure that we are presenting here, the FG-loop is disordered, however, well-ordered in a recently reported homologous rat ZP-C structure. Surprisingly, the adjacent external hydrophobic patch (EHP) segment is registered differently in the rat and murine structures suggesting that this segment only loosely associates with the remaining ZP-C fold. Such a flexible and temporarily-modulated association of the EHP segment with the ZP domain has been proposed to control the polymerization of ZP domain-containing proteins. Our findings suggest that this flexibility also extends to the ZP domain of TGFR-3 and might facilitate co-receptor ligand interaction and presentation via the adjacent FG-loop. This hints that a similar C-terminal region of the ZP domain architecture possibly regulates both the polymerization of extracellular matrix proteins and cytokine ligand recognition of TGFR-3. PMID:23826237
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Chilling response of plants: importance of galactolipase, free fatty acids and free radicals.
Kaniuga, Z
2008-03-01
The chilling response of plants is complex and based on the interplay of two important metabolic processes--lipolytic degradation of membrane lipids and a set of oxidative reactions leading to lipid peroxidation and membrane damage evoked in chilling-sensitive (CS) plants subjected to low temperature and light. The effects of chilling of detached leaves and intact plants differ and are often neglected during experiments. In closely-related species, the activity of several constitutive enzymes (i.e. superoxide dismutase, ascorbate peroxidase and glutathione reductase) appears to be higher in chilling-tolerant (CT) than in CS species; while in several native, closely-related CS species, lipid acyl hydrolase (galactolipase) activity is higher than in CT species. Moreover, in chilling-insensitive (CI) plants, galactolipase activity is very low and is neither activated by detachment of leaves nor under stress conditions in growing plants. Dark and low-temperature treatments of detached leaves of CS species and post-chilling recovery of growing plants in the light activate galactolipase, which is responsible for the release of free fatty acids (FFA), the main substrates of peroxidation by lipoxygenase and free radicals. In several CS species, increased galactolipase activity is an important factor contributing to chilling susceptibility. Thus, it seems likely that enhancement of chilling tolerance may be achieved by genetically suppressing galactolipase in order to reduce both the degradation of chloroplast lipids and the level of released FFA, and thereby avoiding the deleterious action of their peroxidation products on plant tissues.
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Norden, Justin; Smuck, Matthew; Sinha, Aman; Hu, Richard; Tomkins-Lane, Christy
2017-01-01
Research suggests that people with lumbar spinal stenosis (LSS) would benefit from increased physical activity. Yet, to date, we do not have disease-specific activity guidelines for LSS, and the nature of free-living physical activity (performance) in LSS remains unknown. LSS care providers could endorse the 2008 United States Physical Activity Guidelines; however, we do not know if this is realistic. The goal of the present study was to determine the proportion of individuals with LSS meeting the 2008 Guidelines. A secondary goal was to better understand the nature of physical performance in this population. Retrospective study. People from the Lumbar Spinal Stenosis Accelerometry Database, all of whom have both radiographic and clinical LSS and are seeking various treatments for their symptoms. Seven-day accelerometry (functional outcome) and demographics (self-reported). For the present study, we analyzed only baseline data that were obtained before any new treatments. Patients with at least 4 valid days of baseline accelerometry data were included. We determined the proportion of individuals with LSS meeting the 2008 US Physical Activity Guidelines of at least 150 minutes of moderate-vigorous (MV) physical activity per week in bouts of 10 minutes or more. We also used the novel Physical Performance analysis designed by our group to determine time spent in varying intensities of activity. There are no conflicts of interest to disclose. We analyzed data from 75 individuals with a mean age of 68 (SD 9), 37% of whom were male. Three people (4%) were considered Meeting Guidelines (at least 150 MV minutes/week), and 56 (75%) were considered Inactive with not even 1 MV minute/week. With the 10-minute bout requirement removed, 10 of 75 (13%) achieved the 150-minute threshold. The average time spent in sedentary activity was 82%, and of time spent in nonsedentary activity, 99.6% was in the light activity range. In conclusion, the present study confirms that people with
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Prior Flaring as a Complement to Free Magnetic Energy for Forecasting Solar Eruptions
NASA Technical Reports Server (NTRS)
Falconer, David A.; Moore, Ronald L.; Barghouty, Abdulnasser F.; Khazanov, Igor
2012-01-01
From a large database of (1) 40,000 SOHO/MDI line-of-sight magnetograms covering the passage of 1,300 sunspot active regions across the 30 deg radius central disk of the Sun, (2) a proxy of each active region's free magnetic energy measured from each of the active region's central-disk-passage magnetograms, and (3) each active region's full-disk-passage history of production of major flares and fast coronal mass ejections (CMEs), we find new statistical evidence that (1) there are aspects of an active region's magnetic field other than the free energy that are strong determinants of the active region's productivity of major flares and fast CMEs in the coming few days, (2) an active region's recent productivity of major flares, in addition to reflecting the amount of free energy in the active region, also reflects these other determinants of coming productivity of major eruptions, and (3) consequently, the knowledge of whether an active region has recently had a major flare, used in combination with the active region's free-energy proxy measured from a magnetogram, can greatly alter the forecast chance that the active region will have a major eruption in the next few days after the time of the magnetogram. The active-region magnetic conditions that, in addition to the free energy, are reflected by recent major flaring are presumably the complexity and evolution of the field.
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Lee, Joey A; Williams, Skip M; Brown, Dale D; Laurson, Kelly R
2015-01-01
Activity monitors are frequently used to assess activity in many settings. But as technology advances, so do the mechanisms used to estimate activity causing a continuous need to validate newly developed monitors. The purpose of this study was to examine the step count validity of the Yamax Digiwalker SW-701 pedometer (YX), Omron HJ-720 T pedometer (OP), Polar Active accelerometer (PAC) and Actigraph gt3x+ accelerometer (AG) under controlled and free-living conditions. Participants completed five stages of treadmill walking (n = 43) and a subset of these completed a 3-day free-living wear period (n = 37). Manually counted (MC) steps provided a criterion measure for treadmill walking, whereas the comparative measure during free-living was the YX. During treadmill walking, the OP was the most accurate monitor across all speeds (±1.1% of MC steps), while the PAC underestimated steps by 6.7-16.0% per stage. During free-living, the OP and AG counted 97.5% and 98.5% of YX steps, respectively. The PAC overestimated steps by 44.0%, or 5,265 steps per day. The Omron pedometer seems to provide the most reliable and valid estimate of steps taken, as it was the best performer under lab-based conditions and provided comparable results to the YX in free-living. Future studies should consider these monitors in additional populations and settings.
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Pan, Albert C; Cuello, Luis G; Perozo, Eduardo; Roux, Benoît
2011-12-01
The amount of ionic current flowing through K(+) channels is determined by the interplay between two separate time-dependent processes: activation and inactivation gating. Activation is concerned with the stimulus-dependent opening of the main intracellular gate, whereas inactivation is a spontaneous conformational transition of the selectivity filter toward a nonconductive state occurring on a variety of timescales. A recent analysis of multiple x-ray structures of open and partially open KcsA channels revealed the mechanism by which movements of the inner activation gate, formed by the inner helices from the four subunits of the pore domain, bias the conformational changes at the selectivity filter toward a nonconductive inactivated state. This analysis highlighted the important role of Phe103, a residue located along the inner helix, near the hinge position associated with the opening of the intracellular gate. In the present study, we use free energy perturbation molecular dynamics simulations (FEP/MD) to quantitatively elucidate the thermodynamic basis for the coupling between the intracellular gate and the selectivity filter. The results of the FEP/MD calculations are in good agreement with experiments, and further analysis of the repulsive, van der Waals dispersive, and electrostatic free energy contributions reveals that the energetic basis underlying the absence of inactivation in the F103A mutation in KcsA is the absence of the unfavorable steric interaction occurring with the large Ile100 side chain in a neighboring subunit when the intracellular gate is open and the selectivity filter is in a conductive conformation. Macroscopic current analysis shows that the I100A mutant indeed relieves inactivation in KcsA, but to a lesser extent than the F103A mutant.
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Banerjee, Kinshuk; Das, Biswajit; Gangopadhyay, Gautam
2013-04-28
In this paper, we have explored generic criteria of cooperative behavior in ion channel kinetics treating it on the same footing with multistate receptor-ligand binding in a compact theoretical framework. We have shown that the characterization of cooperativity of ion channels in terms of the Hill coefficient violates the standard Hill criteria defined for allosteric cooperativity of ligand binding. To resolve the issue, an alternative measure of cooperativity is proposed here in terms of the cooperativity index that sets a unified criteria for both the systems. More importantly, for ion channel this index can be very useful to describe the cooperative kinetics as it can be readily determined from the experimentally measured ionic current combined with theoretical modelling. We have analyzed the correlation between the voltage value and slope of the voltage-activation curve at the half-activation point and consequently determined the standard free energy of activation of the ion channel using two well-established mechanisms of cooperativity, namely, Koshland-Nemethy-Filmer (KNF) and Monod-Wyman-Changeux (MWC) models. Comparison of the theoretical results for both the models with appropriate experimental data of mutational perturbation of Shaker K(+) channel supports the experimental fact that the KNF model is more suitable to describe the cooperative behavior of this class of ion channels, whereas the performance of the MWC model is unsatisfactory. We have also estimated the mechanistic performance through standard free energy of channel activation for both the models and proposed a possible functional disadvantage in the MWC scheme.
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Takao, Koichi; Toda, Kazuhiro; Saito, Takayuki; Sugita, Yoshiaki
2017-01-01
A series of cinnamic acid derivatives, amides (1-12) and esters (13-22), were synthesized, and structure-activity relationships for antioxidant activity, and monoamine oxidases (MAO) A and B, acetylcholinesterase, and butyrylcholinesterase (BChE) inhibitory activities were analyzed. Among the synthesized compounds, compounds 1-10, 12-18, and rosmarinic acid (23), which contained catechol, o-methoxyphenol or 5-hydroxyindole moieties, showed potent 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity. Compounds 9-11, 15, 17-22 showed potent and selective MAO-B inhibitory activity. Compound 20 was the most potent inhibitor of MAO-B. Compounds 18 and 21 showed moderate BChE inhibitory activity. In addition, compound 18 showed potent antioxidant activity and MAO-B inhibitory activity. In a comparison of the cinnamic acid amides and esters, the amides exhibited more potent DPPH free radical scavenging activity, while the esters showed stronger inhibitory activities against MAO-B and BChE. These results suggested that cinnamic acid derivatives such as compound 18, p-coumaric acid 3,4-dihydroxyphenethyl ester, and compound 20, p-coumaric acid phenethyl ester, may serve as lead compounds for the development of novel MAO-B inhibitors and candidate lead compounds for the prevention or treatment of Alzheimer's disease.
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Free radical-scavenging delta-lactones from Boletus calopus.
Kim, Jin-Woo; Yoo, Ick-Dong; Kim, Won-Gon
2006-12-01
The methanol extracts from the fruiting body of the mushroom Boletus calopus showed free radical-scavenging activity. Bioactivity-guided fractionation of the methanol extracts led to a new hydroxylated calopin named calopin B, along with the known delta-lactones calopin and cyclocalopin A. The structure of the new calopin analogue was elucidated by spectroscopic methods. All compounds showed potent free radical-scavenging activity against superoxide, DPPH, and ABTS radicals with IC (50) values of 1.2 - 5.4 microg/mL.
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Biological Relevance of Free Radicals and Nitroxides.
Prescott, Christopher; Bottle, Steven E
2017-06-01
Nitroxides are stable, kinetically-persistent free radicals which have been successfully used in the study and intervention of oxidative stress, a critical issue pertaining to cellular health which results from an imbalance in the levels of damaging free radicals and redox-active species in the cellular environment. This review gives an overview of some of the biological processes that produce radicals and other reactive oxygen species with relevance to oxidative stress, and then discusses interactions of nitroxides with these species in terms of the use of nitroxides as redox-sensitive probes and redox-active therapeutic agents.
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Hetem, Robyn S; Strauss, W Maartin; Fick, Linda G; Maloney, Shane K; Meyer, Leith C R; Shobrak, Mohammed; Fuller, Andrea; Mitchell, Duncan
2012-12-01
Predicting whether behaviour could buffer the effects of climate change on long-lived mammals requires a better understanding of the long-term behavioural responses of mammals to environmental stress. Using biologging, we measured locomotor activity and microclimate selection, over eight months, in five Arabian oryx (Oryx leucoryx) living free in a Saudi Arabian desert. The oryx displayed seasonal flexibility in activity patterns, shifting from a continuous 24-h activity pattern with crepuscular peaks in cooler months to a predominantly nocturnal activity pattern during the hottest months, without reducing the total 24-h activity level. The proportion of total 24-h activity that occurred during daylight hours was just 29±8% during the hottest months, versus 53±8% (mean±SD, n=5 oryx) in the other months. The attenuation in diurnal activity levels during the hot months was accompanied by the selection of cooler microclimates, presumably via shade seeking, during the heat of the day. Analysis of miniature black globe (miniglobe) temperature from a remote sensor on the collar of two female animals revealed that oryx selected microclimates cooler than the microclimates in direct sun at higher environmental heat loads across all periods, but with enhanced efficiency during the dry periods. We have quantified activity re-assignment and microclimate selection as responses to hot arid conditions in a free-living artiodactyl. Such flexible behavioural processes may act to buffer the adverse effects of the progressively hotter and drier conditions predicted to occur with climate change. Copyright © 2012 Elsevier GmbH. All rights reserved.
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Moses, Vivian; Brookes, Graham
2013-01-01
The rapid global development of agricultural production systems using seeds derived from genetic modification (GM) has been paralleled by the growth of attempts to keep at least a part of the world's agriculture and food as free from GM-crops and their products as possible. The ideal for some proponents of such "GM-free" activity would be a total absence, usually styled "zero content"; others, perhaps more realistically, opt for a definition usually not precisely defined that allows for minimal trace levels of GM material. The reasons for wanting "GM-free" agriculture and its products are varied; they include philosophical and religious beliefs, concern for human (and animal) health--and for "the environment"-as well as commercial and political interests. With such a variety of motivations, and in the absence of legal rulings, the definitions of "GM-free" vary according to inclination and circumstances. Whatever the precise meaning, the maintenance of a "GM-free" product stream in a world where GM crop production is widespread requires the establishment of identity preservation and segregation systems in which traceability and testing are cornerstones. Inevitably these have cost implications for the supply chain and/or the ultimate consumer. In a number of countries different forms of "GM-free" labels exist for some products; the style of such labels is variable with schemes and labels typically voluntary or privately organized. In more recent years, some governments have begun to regularize the definition and meaning of "GM-free." We conclude our analysis by exploring consumer reactions both to "GM-free" and to "GM-free" labels, and ask who ultimately benefits from preserving a product stream substantially or entirely devoid of GM-content.
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Zinnuroglu, Murat; Dincel, Aylin Sepici; Kosova, Funda; Sepici, Vesile; Karatas, Gulcin Kaymak
2012-04-01
In addition to the well-described implications of estrogen deficiency in postmenopausal osteoporosis (PMO), free radicals are also effective on bone metabolism. The antioxidant vitamins C and E play an important role in the production of collagen, mesenchymal cell differentiation into osteoblasts, and bone mineralization. Therefore, the incidence of osteoporosis and the risk of fractures were decreased with vitamin C and E. It was proposed that free oxygen radicals are responsible for biological aging, atherosclerosis, carcinogenesis, and osteoclastic activity via their negative effects on the cell and DNA. In this study, we aimed to investigate and compare the levels of free radicals and serum antioxidant activity in patients with PMO and healthy subjects before and after six-month treatment with risedronate, which is an inhibitor of bone resorption. Twenty-three postmenopausal patients aged between 52-83 (mean [± standard deviation] 67.6 ± 8.17) with T scores below -2.5 in femur neck or L1-L4, and 23 postmenopausal healthy subjects were enrolled into the study. Patients who had received any medications within the last 6 months that could alter bone metabolism were excluded. Serum malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GPx) levels were analyzed in both groups. The patients with PMO were commenced on 5 mg of risedronate, 1,200 mg of calcium, and 800 IU of vitamin D daily. The patients were reevaluated at the end of the sixth month. MDA and SOD levels were similar in patients with PMO when compared to the healthy group before the treatment, while the GPx levels were lower in patients with PMO (P = 0.014). GPx (P = 0.028) and MDA (P = 0.04) levels were increased in patients with PMO after the treatment. In contrast, SOD levels were decreased when compared to the initial levels (P = 0.006). There may be an insufficiency in different steps of the enzymatic antioxidant systems in patients with PMO without treatment. We observed
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Anouar, El Hassane
2014-01-01
Phenolic Schiff bases are known as powerful antioxidants. To select the electronic, 2D and 3D descriptors responsible for the free radical scavenging ability of a series of 30 phenolic Schiff bases, a set of molecular descriptors were calculated by using B3P86 (Becke’s three parameter hybrid functional with Perdew 86 correlation functional) combined with 6-31 + G(d,p) basis set (i.e., at the B3P86/6-31 + G(d,p) level of theory). The chemometric methods, simple and multiple linear regressions (SLR and MLR), principal component analysis (PCA) and hierarchical cluster analysis (HCA) were employed to reduce the dimensionality and to investigate the relationship between the calculated descriptors and the antioxidant activity. The results showed that the antioxidant activity mainly depends on the first and second bond dissociation enthalpies of phenolic hydroxyl groups, the dipole moment and the hydrophobicity descriptors. The antioxidant activity is inversely proportional to the main descriptors. The selected descriptors discriminate the Schiff bases into active and inactive antioxidants. PMID:26784873
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Free Enterprise in the Office Occupations Education Curriculum.
ERIC Educational Resources Information Center
South Carolina State Dept. of Education, Columbia. Office of Vocational Education.
This booklet presents in eight sections competencies, content areas, learning activities, and resources intended to serve as examples of strategies for incorporating free enterprise education in the office occupations education curriculum. Section 1 includes the rationale for studying free enterprise and describes the format and procedures of this…
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Gomersall, Sjaan R; Ng, Norman; Burton, Nicola W; Pavey, Toby G; Gilson, Nicholas D; Brown, Wendy J
2016-09-07
Activity trackers are increasingly popular with both consumers and researchers for monitoring activity and for promoting positive behavior change. However, there is a lack of research investigating the performance of these devices in free-living contexts, for which findings are likely to vary from studies conducted in well-controlled laboratory settings. The aim was to compare Fitbit One and Jawbone UP estimates of steps, moderate-to-vigorous physical activity (MVPA), and sedentary behavior with data from the ActiGraph GT3X+ accelerometer in a free-living context. Thirty-two participants were recruited using convenience sampling; 29 provided valid data for this study (female: 90%, 26/29; age: mean 39.6, SD 11.0 years). On two occasions for 7 days each, participants wore an ActiGraph GT3X+ accelerometer on their right hip and either a hip-worn Fitbit One (n=14) or wrist-worn Jawbone UP (n=15) activity tracker. Daily estimates of steps and very active minutes were derived from the Fitbit One (n=135 days) and steps, active time, and longest idle time from the Jawbone UP (n=154 days). Daily estimates of steps, MVPA, and longest sedentary bout were derived from the corresponding days of ActiGraph data. Correlation coefficients and Bland-Altman plots with examination of systematic bias were used to assess convergent validity and agreement between the devices and the ActiGraph. Cohen's kappa was used to assess the agreement between each device and the ActiGraph for classification of active versus inactive (≥10,000 steps per day and ≥30 min/day of MVPA) comparable with public health guidelines. Correlations with ActiGraph estimates of steps and MVPA ranged between .72 and .90 for Fitbit One and .56 and .75 for Jawbone UP. Compared with ActiGraph estimates, both devices overestimated daily steps by 8% (Fitbit One) and 14% (Jawbone UP). However, mean differences were larger for daily MVPA (Fitbit One: underestimated by 46%; Jawbone UP: overestimated by 50%). There was
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Zhukova, A G; Alekhina, D A; Sazontova, T G; Prokop'ev, Yu A; Gorokhova, L G; Stryapko, N V; Mikhailova, N N
2013-12-01
The mechanisms of intracellular defense and activity of free radical oxidation in the myocardium were studied in the dynamics of chronic fluorine intoxication. At the early stages of fluorine intoxication (day 3-week 3), the concentrations of defense proteins HIF-1α, HSC73, and HOx-2 and activity of the main metabolic enzymes increased, which promoted maintenance of cardiomyocyte structure and function at the normal physiological level. At late stages of fluorine intoxication (weeks 6 and 9), metabolic changes in the myocardium attest to high strain of the adaptive mechanisms.
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Phytochemical screening and free radical scavenging activity of Citrullus colocynthis seeds extracts
Benariba, Nabila; Djaziri, Rabeh; Bellakhdar, Wafaa; Belkacem, Nacera; Kadiata, Marcel; Malaisse, Willy J.; Sener, Abdullah
2013-01-01
Objective To study the phytochemical screening of different extracts from Citrullus colocynthis (C. colocynthis ) seeds extracts and to assess their antioxidant activity on the DPPH free radical scavenging. Methods Phytochemical screening, total content of polyphenols and flavonoids of C. colocynthis seeds extracts, including a crude aqueous extract (E1), a defatted aqueous extract (E2), a hydromethanolic extract (HM), an ethyl acetate extract (EA) and a n-butanol extract (n-B) was carried out according to the standard methods and to assess their corresponding effect on the antioxidant activity of this plant. Results None of these extracts contained detectable amount of alkaloid, quinone, antraquinone, or reducing sugar. Catechic tannins and flavonoids were abundant in E1, HM and EA, whilst terpenoids were abundantly present in E1 and n-B but only weekly in HM. Coumarins were found in E2, EA and n-B. Polyphenols, expressed as gallic acid equivalent, amounted, per 100 g plant matter, to 329, 1002 and 150 mg in EA, HM an E1 respectively. Flavonoids, expressed as catechin equivalent, amounted, per 100 g plant matter to 620, 241 and 94 mg in EA, HM and E1 respectively. Comparable values were found in n-B and E1, with lower values in E2. Quercetin, myricetin and gallic acid were found in the EA and HM extracts by thin layer chromatography, The antioxidative effect of these extracts yielded, when tested at a concentration of 2 000 µg/mL in a 1,1-diphenyl-2-picrylhydrazyl assay, a reducing percentage of 88.8% with EA, 74.5% with HM and 66.2% with E1, and corresponding IC50 of 350, 580 and 500 µg/mL as compared to 1.1 µg/mL for ascorbic acid. Conclusions These qualitative and quantitative analytical data document the presence in C. colocynthis extracts of such chemical compounds as flavonoids responsible for the antioxidant activity, as well as other biological activities of this plant. PMID:23570014
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Drug-Free Platelets Can Act as Seeds for Aggregate Formation During Antiplatelet Therapy
Hoefer, Thomas; Armstrong, Paul C.; Finsterbusch, Michaela; Chan, Melissa V.; Kirkby, Nicholas S.
2015-01-01
Objective— Reduced antiplatelet drug efficacy occurs in conditions of increased platelet turnover, associated with increased proportions of drug-free, that is, uninhibited, platelets. Here, we detail mechanisms by which drug-free platelets promote platelet aggregation in the face of standard antiplatelet therapy. Approach and Results— To model standard antiplatelet therapy, platelets were treated in vitro with aspirin, the P2Y12 receptor blocker prasugrel active metabolite, or aspirin plus prasugrel active metabolite. Different proportions of uninhibited platelets were then introduced. Light transmission aggregometry analysis demonstrated clear positive associations between proportions of drug-free platelets and percentage platelet aggregation in response to a range of platelet agonists. Using differential platelet labeling coupled with advanced flow cytometry and confocal imaging we found aggregates formed in mixtures of aspirin-inhibited platelets together with drug-free platelets were characterized by intermingled platelet populations. This distribution is in accordance with the ability of drug-free platelets to generate thromboxane A2 and so drive secondary platelet activation. Conversely, aggregates formed in mixtures of prasugrel active metabolite–inhibited or aspirin plus prasugrel active metabolite–inhibited platelets together with drug-free platelets were characterized by distinct cores of drug-free platelets. This distribution is consistent with the ability of drug-free platelets to respond to the secondary activator ADP. Conclusions— These experiments are the first to image the interactions of inhibited and uninhibited platelets in the formation of platelet aggregates. They demonstrate that a general population of platelets can contain subpopulations that respond strikingly differently to overall stimulation of the population and so act as the seed for platelet aggregation. PMID:26272940
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Novo, Sergi; Penon, Oriol; Barrios, Leonardo; Nogués, Carme; Santaló, Josep; Durán, Sara; Gómez-Matínez, Rodrigo; Samitier, Josep; Plaza, José Antonio; Pérez-García, Luisa; Ibáñez, Elena
2013-06-01
Is the attachment of biofunctionalized polysilicon barcodes to the outer surface of the zona pellucida an effective approach for the direct tagging and identification of cultured embryos? The results achieved provide a proof of concept for a direct embryo tagging system using biofunctionalized polysilicon barcodes, which could help to minimize the risk of mismatching errors (mix-ups) in human assisted reproduction technologies. Even though the occurrence of mix-ups is rare, several cases have been reported in fertility clinics around the world. Measures to prevent the risk of mix-ups in human assisted reproduction technologies are therefore required. Mouse embryos were tagged with 10 barcodes and the effectiveness of the tagging system was tested during fresh in vitro culture (n=140) and after embryo cryopreservation (n = 84). Finally, the full-term development of tagged embryos was evaluated (n =105). Mouse pronuclear embryos were individually rolled over wheat germ agglutinin-biofunctionalized polysilicon barcodes to distribute them uniformly around the ZONA PELLUCIDA surface. Embryo viability and retention of barcodes were determined during 96 h of culture. The identification of tagged embryos was performed every 24 h in an inverted microscope and without embryo manipulation to simulate an automatic reading procedure. Full-term development of the tagged embryos was assessed after their transfer to pseudo-pregnant females. To test the validity of the embryo tagging system after a cryopreservation process, tagged embryos were frozen at the 2-cell stage using a slow freezing protocol, and followed in culture for 72 h after thawing. Neither the in vitro or in vivo development of tagged embryos was adversely affected. The tagging system also proved effective during an embryo cryopreservation process. Global identification rates higher than 96 and 92% in fresh and frozen-thawed tagged embryos, respectively, were obtained when simulating an automatic barcode reading
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NASA Astrophysics Data System (ADS)
Liu, Kong; Lu, Shudi; Yue, Shizhong; Ren, Kuankuan; Azam, Muhammad; Tan, Furui; Wang, Zhijie; Qu, Shengchun; Wang, Zhanguo
2016-11-01
To enable organic solar cells with a competent charge transport efficiency, reducing the thickness of active layer without sacrificing light absorption efficiency turns out to be of high feasibility. Herein, organic solar cells on wrinkled metal surface are designed. The purposely wrinkled Al/Au film with a smooth surface provides a unique scaffold for constructing thin organic photovoltaic devices by avoiding pinholes and defects around sharp edges in conventional nanostructures. The corresponding surface light trapping effect enables the thin active layer (PTB7-Th:PC71BM) with a high absorption efficiency. With the innovative MoO3/Ag/ZnS film as the top transparent electrode, the resulting Indium Tin Oxide-free wrinkled devices show a power conversion efficiency as 7.57% (50 nm active layer), higher than the planner counterparts. Thus, this paper provides a new methodology to improve the performance of organic solar cells by balancing the mutual restraint factors to a high level.
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ZIF-8 derived nitrogen-doped porous carbon as metal-free catalyst of peroxymonosulfate activation.
Ma, Wenjie; Du, Yunchen; Wang, Na; Miao, Peng
2017-07-01
Nitrogen-doped porous carbon (NPC) is synthesized through a direct pyrolysis of zeolitic imidazolate framework (ZIF)-8 under N 2 flow followed by acid washing process. It is found that NPC-800 pyrolyzed at 800 °C can inherit the perfect rhombic dodecahedron morphology of ZIF-8 crystals and achieve the considerable nitrogen-doping content of 15.20%. When NPC-800 is applied as the heterogeneous catalyst in peroxymonosulfate (PMS) activation for the degradation of Rhodamine B (RhB) and phenol, NPC-800 will exhibit its better performance than some conventional transition metal-based oxides and common carbon materials. The active sites can be primarily ascribed to nitrogen modification and sp 2 -hybridized carbon frameworks. Besides, the influence of several parameters such as the dosage of catalyst, the concentration of oxidant, and reaction temperature is conducted systematically. More importantly, NPC-800 can maintain its considerable degradation in the presence of some anions and natural organic matters, even under some actual water background conditions. Although NPC-800 displays mild deactivation in repeated experiments, its catalytic performance can be easily recovered through heat treatment at 350 °C in air. Radical quenching tests reveal that both sulfate and hydroxyl radicals are responsible for the removal of organic pollutants. This research may provide a new way for the application of novel metal-free carbocatalysts in terms of PMS activation.
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Krauss, Ulrich; Jäger, Vera D; Diener, Martin; Pohl, Martina; Jaeger, Karl-Erich
2017-09-20
Bacterial inclusion bodies (IBs) consist of unfolded protein aggregates and represent inactive waste products often accumulating during heterologous overexpression of recombinant genes in Escherichia coli. This general misconception has been challenged in recent years by the discovery that IBs, apart from misfolded polypeptides, can also contain substantial amounts of active and thus correctly or native-like folded protein. The corresponding catalytically-active inclusion bodies (CatIBs) can be regarded as a biologically-active sub-micrometer sized biomaterial or naturally-produced carrier-free protein immobilizate. Fusion of polypeptide (protein) tags can induce CatIB formation paving the way towards the wider application of CatIBs in synthetic chemistry, biocatalysis and biomedicine. In the present review we summarize the history of CatIBs, present the molecular-biological tools that are available to induce CatIB formation, and highlight potential lines of application. In the second part findings regarding the formation, architecture, and structure of (Cat)IBs are summarized. Finally, an overview is presented about the available bioinformatic tools that potentially allow for the prediction of aggregation and thus (Cat)IB formation. This review aims at demonstrating the potential of CatIBs for biotechnology and hopefully contributes to a wider acceptance of this promising, yet not widely utilized, protein preparation. Copyright © 2017 Elsevier B.V. All rights reserved.
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Yamanaka, Atsushi; Pitaksajjakul, Pannamthip; Ramasoota, Pongrama; Konishi, Eiji
2015-11-09
Most candidate dengue vaccines currently under development induce neutralizing antibodies, which are considered important for immunoprotection. However, the concomitant induction of infection-enhancing antibodies is an unavoidable concern. In contrast, a neutralizing antibody developed for passive immunotherapy has been engineered to eliminate its enhancing activity. Therefore, a strategy for the long-term expression of enhancing-activity-free neutralizing antibodies may resolve this concern. A mouse monoclonal antibody, 7F4, of the IgG3 subclass and with no detectable enhancing activity, was selected as the model neutralizing antibody to evaluate the potential of this strategy. Equal amounts of commercial vector (pFUSE)-based plasmids containing 7F4 heavy (H)- or light (L)-chain variable region genes were mixed and used for the cotransfection of 293T cells and co-delivery into ICR and BALB/c mice. The recombinant plasmids were designed to express IgG2b or IgG3 subclass antibodies (p7F4G2b or p7F4G3, respectively). 293T cells transfected with 2 μg of p7F4G2b or p7F4G3 produced approximately 15,000 or 800 ng/ml IgG in the culture fluids, respectively. The dose is expressed as the total amount of H- and L-chain plasmids. Neutralizing antibody was detected dose-dependently in ICR mice inoculated with 50-200 μg of p7F4G2b. A 1:2 dilution of sera from ICR and BALB/c mice inoculated with 100 μg of p7F4G3 showed average plaque reduction levels of >70% on day 3 and >90% on days 5-9. BALB/c mice maintained detectable neutralizing antibody for at least 3 months. The neutralizing antibody expressed by p7F4G3 in mice showed no enhancing activity. Although the expression of neutralizing antibodies from immunoglobulin genes is a type of passive immunization, its durability can be utilized as a dengue vaccine strategy. This "proof-of-concept" study using a mouse model demonstrates that the enhancing-activity-free characteristic of this strategy augurs well for dengue vaccine
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[From free radicals to science of nutrition].
Blázovics, Anna
2009-01-11
During the decades of free radical research, we came ever closer to the knowledge that the free radical-antioxidant balance of the organs is modified fundamentally by the genetic background and surroundings. Janus-face oxygen free radicals are the secondary messengers of signal transduction routes and simultaneously they are cytotoxic agents of cells. The activation of signal transduction proteins by moderate oxidation effects and metal ions is not fairly known yet. The molecular mechanism between activators and inhibitors of signal transduction is controlled in a fine way. The balance of antioxidant-prooxidant levels of the cells can go back to the concentration relation of sulfhydril groups and disulfid bridges. Essential and toxic metal ions and selenium can play an important role in the redox homeostasis. Healthy tissues have many antioxidants, hereby they ensure the protection of the organs against free radicals. Alimentary antioxidants such as vitamin A, C and E, polyphenols, anthocyanins, flavonoids, isothiocyanates and other bioactive molecules in their natural molecular structure and derivates are able to influence the redox reactions. In our days more and more molecules from foods, or their metabolites are verified to act on genes based on the results of molecular biological research.
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Ti, Huihui; Li, Qing; Zhang, Ruifen; Zhang, Mingwei; Deng, Yuanyuan; Wei, Zhencheng; Chi, Jianwei; Zhang, Yan
2014-09-15
This study quantified free and bound phytochemicals and their antioxidant activity in the endosperm and bran/embryo of different indica rice varieties. Phytochemicals mainly existed as free form in the bran/embryo and as both free and bound forms in the endosperm. The average values of total phenolic content, flavonoid content, FRAP, ABTS and ORAC values in the bran/embryo were 3.1, 10.4, 8.2, 11.2 and 11.4 times higher than those in the endosperm, respectively. In whole brown rice, the bran contributed 59.2%, 53.7%, 47.7%, 55.5% and 56.9% of total phenolics, flavonoids, FRAP, ABTS and ORAC values, respectively. Seven individual phenolics (gallic, protocatechuic, chlorogenic, caffeic, syringic, coumaric and ferulic acids) were detected with most coumaric and ferulic acids in the bran. All measurements exhibited varietal differences. These findings provide important information for improving human health by encouraging the consumption of whole brown rice and its use in food product development. Copyright © 2014 Elsevier Ltd. All rights reserved.
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James-Kracke, M R; Sexe, R B; Shukla, S D
1994-11-01
The purpose of this study was to investigate signal transduction mechanisms activated by low and high concentrations of platelet-activating factor (PAF) in rabbit platelets and to contrast the responses to those induced by thrombin. We measured changes in intracellular free calcium ([Ca++]i) with fura2, while monitoring light scatter simultaneously as a measure of shape change and aggregation in a dual-excitation dual-emission spectrofluorometer. An abrupt 20% fall in light scatter, coincident with the peak of the [Ca++]i, indicated shape change in Ca-containing or Ca-free medium and was blocked by BAPTA loading and 10 microM cytochalasin B. A secondary decline in light scatter, indicating aggregation, occurred only in Ca-containing medium and only under conditions favoring protein kinase C (PKC) activation. PAF at 10(-12) M did not increase 1,4,5-inositol triphosphate content, which suggested PKC would not be activated. However, PAF at 10(-12) rapidly increased [Ca++]i to 900 nM in 7 sec seemingly by Ca influx through receptor-operated channels inducing shape change. PAF at 10(-9) and 10(-8) M increased [Ca++]i to 2 microM in 12 sec and induced both shape change and aggregation. However, in platelets pretreated with 100 nM staurosporine to inhibit protein kinases, 10(-9) M PAF did not cause aggregation even though [Ca++]i still rose to 2 microM, which indicated that PKC plays a role in aggregation but not in Ca++ mobilization.(ABSTRACT TRUNCATED AT 250 WORDS)
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Laverty, Anthony; Mindell, Jenny; Millett, Chris
2016-01-01
Objectives. We investigated associations between having a bus pass, enabling free local bus travel across the United Kingdom for state pension–aged people, and physical activity, gait speed, and adiposity. Methods. We used data on 4650 bus pass–eligible people (aged ≥ 62 years) at wave 6 (2012–2013) of the English Longitudinal Study of Ageing in regression analyses. Results. Bus pass holders were more likely to be female (odds ratio [OR] = 1.67; 95% confidence interval [CI] = 1.38, 2.02; P < .001), retired (OR = 2.65; 95% CI = 2.10, 3.35; P < .001), without access to a car (OR = 2.78; 95% CI = 1.83, 4.21; P < .001), to use public transportation (OR = 10.26; 95% CI = 8.33, 12.64; P < .001), and to be physically active (OR = 1.43; 95% CI = 1.12, 1.84; P = .004). Female pass holders had faster gait speed (b = 0.06 meters per second; 95% CI = 0.02, 0.09; P = .001), a body mass index 1 kilogram per meter squared lower (b = –1.20; 95% CI = –1.93, –0.46; P = .001), and waist circumference 3 centimeters smaller (b = –3.32; 95% CI = –5.02, –1.62; P < .001) than women without a pass. Conclusions. Free bus travel for older people helps make transportation universally accessible, including for those at risk for social isolation. Those with a bus pass are more physically active. Among women in particular, the bus pass is associated with healthier aging. PMID:26562118
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Serum biochemistry of captive and free-ranging gray wolves (Canis lupus)
Constable, Peter; Hinchcliff, Ken; Demma, Nick; Callahan, Margaret; Dale, B.W.; Fox, Kevin; Adams, Layne G.; Wack, Ray; Kramer, Lynn
1998-01-01
Normal serum biochemistry values are frequently obtained from studies of captive sedentary (zoo) or free-ranging (wild) animals. It is frequently assumed that values from these two populations are directly referable to each other. We tested this assumption using 20 captive gray wolves (Canis lupus) in Minnesota, USA, and 11 free-ranging gray wolves in Alaska, USA. Free-ranging wolves had significantly (P<0.05) lower sodium, chloride, and creatine concentrations and significantly higher potassium and blood urea nitrogen (BUN) concentrations; BUN to creatine ratios; and alanine aminotransferase, aspartate aminotransferase, and creatine kinase activities relative to captive wolves. Corticosteroid-induced alkaline phosphatase activity (a marker of stress in domestic dogs) was detected in 3 of 11 free-ranging wolves and in 0 of 20 captive wolves (P = 0.037). This study provides clear evidence that serum biochemical differences can exist between captive and free-ranging populations of one species. Accordingly, evaluation of the health status of an animal should incorporate an understanding of the potential confounding effect that nutrition, activity level, and environmental stress could have on the factor(s) being measured.
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NASA Astrophysics Data System (ADS)
Liu, Junliang; Zhang, Tingfa; Li, Yongfu; Ding, Lei; Tao, Junchao; Wang, Ying; Wang, Qingpu; Fang, Jiaxiong
2017-07-01
A free-running single-photon detector for 1.06 μm wavelength based on an InGaAsP/InP single-photon avalanche diode is presented. The detector incorporates an ultra-fast active-quenching technique to greatly lessen the afterpulsing effects. An improved method for avalanche characterization using electroluminescence is proposed, and the performance of the detector is evaluated. The number of avalanche carriers is as low as 1.68 ×106 , resulting in a low total afterpulse probability of 4% at 233 K, 10% detection efficiency, and 1 μs hold-off time.
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Mäki, Netta; Martikainen, Pekka; Eikemo, Terje; Menvielle, Gwenn; Lundberg, Olle; Ostergren, Olof; Jasilionis, Domantas; Mackenbach, Johan P
2013-10-01
Healthy life expectancy is a composite measure of length and quality of life and an important indicator of health in aging populations. There are few cross-country comparisons of socioeconomic differences in healthy life expectancy. Most of the existing comparisons focus on Western Europe and the United States, often relying on older data. To address these deficiencies, we estimated educational differences in disability-free life expectancy for eight countries from all parts of Europe in the early 2000s. Long-standing severe disability was measured as a Global Activity Limitation Indicator (GALI) derived from the European Union Statistics on Income and Living Conditions (EU-SILC) survey. Census-linked mortality data were collected by a recent project comparing health inequalities between European countries (the EURO-GBD-SE project). We calculated sex-specific educational differences in disability-free life expectancy between the ages of 30 and 79 years using the Sullivan method. The lowest disability-free life expectancy was found among Lithuanian men and women (33.1 and 39.1 years, respectively) and the highest among Italian men and women (42.8 and 44.4 years, respectively). Life expectancy and disability-free life expectancy were directly related to the level of education, but the educational differences were much greater in the latter in all countries. The difference in the disability-free life expectancy between those with a primary or lower secondary education and those with a tertiary education was over 10 years for males in Lithuania and approximately 7 years for males in Austria, Finland and France, as well as for females in Lithuania. The difference was smallest in Italy (4 and 2 years among men and women, respectively). Highly educated Europeans can expect to live longer and spend more years in better health than those with lower education. The size of the educational difference in disability-free life expectancy varies significantly between countries
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Radon free storage container and method
Langner, Jr., G. Harold; Rangel, Mark J.
1991-01-01
A radon free containment environment for either short or long term storage of radon gas detectors can be provided as active, passive, or combined active and passive embodiments. A passive embodiment includes a resealable vessel containing a basket capable of holding and storing detectors and an activated charcoal adsorbing liner between the basket and the containment vessel wall. An active embodiment includes the resealable vessel of the passive embodiment, and also includes an external activated charcoal filter that circulates the gas inside the vessel through the activated charcoal filter. An embodiment combining the active and passive embodiments is also provided.
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Yang, Yan; Geng, Chao; Li, Feng; Huang, Guan; Li, Xinyang
2017-10-30
Multi-aperture receiver with optical combining architecture is an effective approach to overcome the turbulent atmosphere effect on the performance of the free-space optical (FSO) communications, in which how to combine the multiple laser beams received by the sub-apertures efficiently is one of the key technologies. In this paper, we focus on the combining module based on fiber couplers, and propose the all-fiber coherent beam combining (CBC) with two architectures by using active phase locking. To validate the feasibility of the proposed combining module, corresponding experiments and simulations on the CBC of four laser beams are carried out. The experimental results show that the phase differences among the input beams can be compensated and the combining efficiency can be stably promoted by active phase locking in CBC with both of the two architectures. The simulation results show that the combining efficiency fluctuates when turbulent atmosphere is considered, and the effectiveness of the combining module decreases as the turbulence increases. We believe that the combining module proposed in this paper has great potential, and the results can provide significant advices for researchers when building such a multi-aperture receiver with optical combining architecture for FSO commutation systems.
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Lim, Shaun W.; Lance, Shea T.; Stedman, Kenneth M.; Abate, Adam R.
2017-01-01
Characterizing virus-host relationships is critical for understanding the impact of a virus on an ecosystem, but is challenging with existing techniques, particularly for uncultivable species. We present a general, cultivation-free approach for identifying phage-associated bacterial cells. Using PCR-activated cell sorting, we interrogate millions of individual bacteria for the presence of specific phage nucleic acids. If the nucleic acids are present, the bacteria are recovered via sorting and their genomes analyzed. This allows targeted recovery of all possible host species in a diverse population associated with a specific phage, and can be easily targeted to identify the hosts of different phages by modifying the PCR primers used for detection. Moreover, this technique allows quantification of free phage particles, as benchmarked against the “gold standard” of virus enumeration, the plaque assay. PMID:28042018
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Lim, Shaun W; Lance, Shea T; Stedman, Kenneth M; Abate, Adam R
2017-04-01
Characterizing virus-host relationships is critical for understanding the impact of a virus on an ecosystem, but is challenging with existing techniques, particularly for uncultivable species. We present a general, cultivation-free approach for identifying phage-associated bacterial cells. Using PCR-activated cell sorting, we interrogate millions of individual bacteria for the presence of specific phage nucleic acids. If the nucleic acids are present, the bacteria are recovered via sorting and their genomes analyzed. This allows targeted recovery of all possible host species in a diverse population associated with a specific phage, and can be easily targeted to identify the hosts of different phages by modifying the PCR primers used for detection. Moreover, this technique allows quantification of free phage particles, as benchmarked against the "gold standard" of virus enumeration, the plaque assay. Copyright © 2017 Elsevier B.V. All rights reserved.
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Physiologic data associated with different strains of common laboratory rat strains.This dataset is associated with the following publication:Gordon , C., P. Phillips , and A. Johnstone. Impact of Genetic Strain on Body Fat Loss, Food Consumption, Metabolism, Ventilation, and Motor Activity in Free Running Female Rats. PHYSIOLOGY AND BEHAVIOR. Elsevier Science Ltd, New York, NY, USA, 153: 56-63, (2016).
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Ni, Liang; Shi, Wei-Yong
2014-01-01
In this study, we measured the composition and free radical scavenging activity of several species of nuts, namely, Torreya grandis, Carya cathayensis, and Myrica rubra. The nut kernels of the aforementioned species are rich in fatty acids, particularly in unsaturated fatty acids, and have 51% oil content. T. grandis and C. cathayensis are mostly produced in ZheJiang province. The trace elements in the kernels of T. grandis and C. cathayensis were generally higher than those in M. rubra, except for Fe with a value of 64.41 mg/Kg. T. grandis is rich in selenium (52.91−68.71 mg/Kg). All three kernel oils have a certain free radical scavenging capacity, with the highest value in M. rubra. In the DPPH assay, the IC50 of M. rubra kernel oil was 60 μg/mL, and OH was 100 μg/mL. The results of this study provide basic data for the future development of the edible nut resources in ZheJiang province. PMID:24734074
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Tadić, Vanja M; Dobrić, Silva; Marković, Goran M; Dordević, Sofija M; Arsić, Ivana A; Menković, Nebojsa R; Stević, Tanja
2008-09-10
Hawthorn [Crataegus monogyna Jacq. and Crataegus oxyacantha L.; sin. Crataegus laevigata (Poiret) DC., Rosaceae] leaves, flowers, and berries are used in traditional medicine in the treatment of chronic heart failure, high blood pressure, arrhythmia, and various digestive ailments, as well as geriatric and antiarteriosclerosis remedies. According to European Pharmacopoeia 6.0, hawthorn berries consist of the dried false fruits of these two species or their mixture. The present study was carried out to test free-radical-scavenging, anti-inflammatory, gastroprotective, and antimicrobial activities of hawthorn berries ethanol extract. Phenolic compounds represented 3.54%, expressed as gallic acid equivalents. Determination of total flavonoid aglycones content yielded 0.18%. The percentage of hyperoside, as the main flavonol component, was 0.14%. With respect to procyanidins content, the obtained value was 0.44%. DPPH radical-scavenging capacity of the extract was concentration-dependent, with EC50 value of 52.04 microg/mL (calculation based on the total phenolic compounds content in the extract). Oral administration of investigated extract caused dose-dependent anti-inflammatory effect in a model of carrageenan-induced rat paw edema. The obtained anti-inflammatory effect was 20.8, 23.0, and 36.3% for the extract doses of 50, 100, and 200 mg/kg, respectively. In comparison to indomethacin, given in a dose producing 50% reduction of rat paw edema, the extract given in the highest tested dose (200 mg/kg) showed 72.4% of its activity. Gastroprotective activity of the extract was investigated using an ethanol-induced acute stress ulcer in rats with ranitidine as a reference drug. Hawthorn extract produced dose-dependent gastroprotective activity (3.8 +/- 2.1, 1.9 +/- 1.7, and 0.7 +/- 0.5 for doses of 50, 100, and 200 mg/kg, respectively), with the efficacy comparable to that of the reference drug. Antimicrobial testing of the extract revealed its moderate bactericidal
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Tang, Yujiao; Debnath, Trishna; Choi, Eun-Ju; Kim, Young Wook; Ryu, Jung Pyo; Jang, Sejin; Chung, Sang Uk; Choi, Young-Jin; Kim, Eun-Kyung
2018-01-01
Tenebrio molitor (T. molitor) larvae provide food at low environmental cost and contribute positively to livelihoods. In this research, we compared the amino acids compositions and antioxidant activities of various extracts of T. molitor to enhance their quality as food. For the comparison, distilled water extracts, enzymatic hydrolysates, and condensed enzymatic hydrolysates of T. molitor larvae were prepared. Their amino acids (AAs) profiles and antioxidant activities, including ferric-reducing antioxidant power, oxygen radical absorption capacity, and DPPH, hydroxyl radical, and hydrogen peroxide radical scavenging properties assay were analyzed. DW extracts had the lowest AAs contents and antioxidant activity compared with enzymatic extracts. Condensed hydrolysates with a combination of alcalase and flavourzyme (C-A+F) exhibited the highest levels of total free AAs (11.1759 g/100 g). C-A+F produced higher total hydrolyzed AAs (32.5292 g/100 g) compared with the other groups. The C-A+F possessed the strongest antioxidant activity. Notably, the antioxidant activities of the hydrolysates and the total hydrolyzed AAs amount were correlated. Taken together, our findings showed that C-A+F was a promising technique for obtaining extracts of T. molitor larvae with antioxidant activity as potential nutritious functional food.
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Mapping the potential beverage quality of coffee produced in the Zona da Mata, Minas Gerais, Brazil.
Silva, Samuel de Assis; de Queiroz, Daniel Marçal; Ferreira, Williams Pinto Marques; Corrêa, Paulo Cesar; Rufino, José Luis Dos Santos
2016-07-01
Detailed knowledge of coffee production systems enables optimization of crop management, harvesting and post-harvest techniques. In this study, coffee quality is mapped as a function of coffee variety, altitude and terrain aspect attributes. The work was performed in the Zona da Mata, Minas Gerais, Brazil. A large range of coffee quality grades was observed for the Red Catuai variety. For the Yellow Catuai variety, no quality grades lower than 70 were observed. Regarding the terrain aspect, samples from the southeast-facing slope (SEFS) and the northwest-facing slope (NWFS) exhibited distinct behaviors. The SEFS samples had a greater range of quality grades than did the NWFS samples. The highest grade was obtained from an NWFS point. The lowest quality values and the largest range of grades were observed at lower altitudes. The extracts from the highest-altitude samples did not produce any low-quality coffee. The production site's position and altitude are the primary variables that influenced the coffee quality. The study area has micro-regions with grades ranging from 80 to 94. These areas have the potential for producing specialty coffees. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.
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Powell, Joshua; Luh, Jeanne; Coronell, Orlando
2014-01-01
We studied the volume-averaged chlorine (Cl) uptake into the bulk region of the aromatic polyamide active layer of a reverse osmosis membrane upon exposure to free chlorine. Volume-averaged measurements were obtained using Rutherford backscattering spectrometry with samples prepared at a range of free chlorine concentrations, exposure times, and mixing, rinsing, and pH conditions. Our volume-averaged measurements complement previous studies that have quantified Cl uptake at the active layer surface (top ≈ 7 nm) and advance the mechanistic understanding of Cl uptake by aromatic polyamide active layers. Our results show that surface Cl uptake is representative of and underestimates volume-averaged Cl uptake under acidic conditions and alkaline conditions, respectively. Our results also support that (i) under acidic conditions, N-chlorination followed by Orton rearrangement is the dominant Cl uptake mechanism with N-chlorination as the rate-limiting step; (ii) under alkaline conditions, N-chlorination and dechlorination of N-chlorinated amide links by hydroxyl ion are the two dominant processes; and (iii) under neutral pH conditions, the rates of N-chlorination and Orton rearrangement are comparable. We propose a kinetic model that satisfactorily describes Cl uptake under acidic and alkaline conditions, with the largest discrepancies between model and experiment occurring under alkaline conditions at relatively high chlorine exposures.
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Yin, Dongguang; Liu, Yumin; Zhao, Feifei; Zhang, Xinyu; Zhang, Tingting; Wu, Chenglong; Chang, Na; Chen, Zhiwen
2018-05-01
It has been reported that coupling TiO2 with rare earth upconversion nanocrystals (UCNCs) is an efficient strategy to significantly improve photocatalytic activity of TiO2. However, the rare earth materials are scarcity and cost, and the synthesis process of UCNCs using the rare earth materials is complicated. In the present study, we have designed a new approach using a rare earth-free upconversion nanocrystal (REF-UCNCs) as upconversion luminescent material to replace the rare earth UCNCs. A novel nanocomposite photocatalyst of REF-UCNCs@P25: Mo/GN was developed for the first time. Based on the designed structure, the REF-UCNCs, Mo-doping, and GN (graphene) have a synergistic effect that can improve catalytic activity of P25 significantly. The results of photocatalytic experiments using RhB as a model pollutant under simulated solar light irradiation show that the photocatalytic efficiency of the as-prepared catalyst is 3-folds higher than that of benchmark substance P25. This work provides a new strategy for efficiently improving catalytic activity of semiconductor photocatalysts by coupling with REF-UCNCs. This approach is facile and low-cost which can be widely applied for modification of semiconductor photocatalysts and facilitates their applications in environmental protection issues using solar light.
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Microfluidic sieve using intertwined, free-standing carbon nanotube mesh as active medium
Bakajin, Olgica; Noy, Aleksandr
2007-11-06
A microfluidic sieve having a substrate with a microfluidic channel, and a carbon nanotube mesh. The carbon nanotube mesh is formed from a plurality of intertwined free-standing carbon nanotubes which are fixedly attached within the channel for separating, concentrating, and/or filtering molecules flowed through the channel. In one embodiment, the microfluidic sieve is fabricated by providing a substrate having a microfluidic channel, and growing the intertwined free-standing carbon nanotubes from within the channel to produce the carbon nanotube mesh attached within the channel.
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Chen, C-Y Oliver; Blumberg, Jeffrey B
2008-06-25
Observational studies and clinical trials suggest nut intake, including almonds, is associated with an enhancement in antioxidant defense and a reduction in the risk of cancer and cardiovascular disease. Almond skins are rich in polyphenols (ASP) that may contribute to these putative benefits. To assess their potential mechanisms of action, we tested the in vitro effect of ASP extracted with methanol (M) or a gastrointestinal juice mimic (GI) alone or in combination with vitamins C (VC) or E (VE) (1-10 micromol/L) on scavenging free radicals and inducing quinone reductase (QR). Flavonoid profiles from ASP-M and -GI extracts were different from one another. ASP-GI was more potent in scavenging HOCl and ONOO (-) radicals than ASP-M. In contrast, ASP-M increased and ASP-GI decreased QR activity in Hepa1c1c7 cells. Adding VC or VE to ASP produced a combination- and dose-dependent action on radical scavenging and QR induction. In comparison to their independent actions, ASP-M plus VC were less potent in scavenging DPPH, HOCl, ONOO (-), and O 2 (-) (*). However, the interaction between ASP-GI plus VC promoted their radical scavenging activity. Combining ASP-M plus VC resulted in a synergistic interaction, inducing QR activity, but ASP-GI plus VC had an antagonistic effect. On the basis of their total phenolic content, the measures of total antioxidant activity of ASP-M and -GI were comparable. Thus, in vitro, ASP act as antioxidants and induce QR activity, but these actions are dependent upon their dose, method of extraction, and interaction with antioxidant vitamins.
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Wang, Ying; Zhu, Yingjing; Binyam, Atsebeha; Liu, Misha; Wu, Yinan; Li, Fengting
2016-12-15
A label-free sensing strategy based on the enzyme-mimicking activity of MOF was demonstrated for colorimetric detection of biomolecules. Firstly obvious blue color was observed due to the high efficiency of peroxidase-like catalytic activity of Fe-MIL-88A (an ion-based MOF material) toward 3,3',5,5'-tetramethylbenzidine (TMB). Then in the presence of target biomolecule and corresponding aptamer, the mimetic activity of Fe-MIL-88A can be strongly inhibited and used directly to realize the colorimetric detection. On the basis of the interesting findings, we designed a straightforward, label-free and sensitive colorimetric method for biomolecule detection by using the enzyme mimetic property of MOF coupling with molecular recognition element. Compared with the existed publications, our work breaks the routine way by setting up an inorganic-organic MOF-aptamer hybrid platform for colorimetric determination of biomolecules, expanding the targets scope from H2O2 or glucose to biomolecules. As a proof of concept, thrombin and thrombin aptamer was used as a model analyte. The limit of detection of 10nM can be achieved with naked eyes and ultrahigh selectivity of thrombin toward numerous interfering substances with 10-fold concentration was demonstrated significantly. Of note, the method was further applied for the detection of thrombin in human serum samples, showing the results in agreement with those values obtained in an immobilization buffer by the colorimetric method. This inorganic-organic MOF-aptamer sensing strategy may in principle be universally applicable for the detection of a range of environmental or biomedical molecules of interests. Copyright © 2016 Elsevier B.V. All rights reserved.
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Wang, Xixian; Ren, Lihui; Su, Yetian; Ji, Yuetong; Liu, Yaoping; Li, Chunyu; Li, Xunrong; Zhang, Yi; Wang, Wei; Hu, Qiang; Han, Danxiang; Xu, Jian; Ma, Bo
2017-11-21
Raman-activated cell sorting (RACS) has attracted increasing interest, yet throughput remains one major factor limiting its broader application. Here we present an integrated Raman-activated droplet sorting (RADS) microfluidic system for functional screening of live cells in a label-free and high-throughput manner, by employing AXT-synthetic industrial microalga Haematococcus pluvialis (H. pluvialis) as a model. Raman microspectroscopy analysis of individual cells is carried out prior to their microdroplet encapsulation, which is then directly coupled to DEP-based droplet sorting. To validate the system, H. pluvialis cells containing different levels of AXT were mixed and underwent RADS. Those AXT-hyperproducing cells were sorted with an accuracy of 98.3%, an enrichment ratio of eight folds, and a throughput of ∼260 cells/min. Of the RADS-sorted cells, 92.7% remained alive and able to proliferate, which is equivalent to the unsorted cells. Thus, the RADS achieves a much higher throughput than existing RACS systems, preserves the vitality of cells, and facilitates seamless coupling with downstream manipulations such as single-cell sequencing and cultivation.
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Dialogue between E. coli free radical pathways and the mitochondria of C. elegans.
Govindan, J Amaranath; Jayamani, Elamparithi; Zhang, Xinrui; Mylonakis, Eleftherios; Ruvkun, Gary
2015-10-06
The microbial world presents a complex palette of opportunities and dangers to animals, which have developed surveillance and response strategies to hints of microbial intent. We show here that the mitochondrial homeostatic response pathway of the nematode Caenorhabditis elegans responds to Escherichia coli mutations that activate free radical detoxification pathways. Activation of C. elegans mitochondrial responses could be suppressed by additional mutations in E. coli, suggesting that C. elegans responds to products of E. coli to anticipate challenges to its mitochondrion. Out of 50 C. elegans gene inactivations known to mediate mitochondrial defense, we found that 7 genes were required for C. elegans response to a free radical producing E. coli mutant, including the bZip transcription factor atfs-1 (activating transcription factor associated with stress). An atfs-1 loss-of-function mutant was partially resistant to the effects of free radical-producing E. coli mutant, but a constitutively active atfs-1 mutant growing on wild-type E. coli inappropriately activated the pattern of mitochondrial responses normally induced by an E. coli free radical pathway mutant. Carbonylated proteins from free radical-producing E. coli mutant may directly activate the ATFS-1/bZIP transcription factor to induce mitochondrial stress response: feeding C. elegans with H2O2-treated E. coli induces the mitochondrial unfolded protein response, and inhibition of a gut peptide transporter partially suppressed C. elegans response to free radical damaged E. coli.
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Electromagnetic pulse reduces free radical generation in rat liver mitochondria in vitro.
Wang, C; Zhou, H; Peng, R; Wang, L; Su, Z; Chen, P; Wang, S; Wang, S; Liu, Y; Cong, J; Wu, K; Hu, X; Fan, E
2013-04-01
Non-ionizing radiation electromagnetic pulse (EMP) is generally recorded to induce the generation of free radicals in vivo. Though mitochondria are the primary site to produce free radicals, a rare report is designed to directly investigate the EMP effects on free radical generation at mitochondrial level. Thus the present work was designed to study how EMP induces free radical generation in rat liver mitochondria in vitro using electron paramagnetic resonance technique. Surprisingly, our data suggest that EMP prevents free radical generation by activating antioxidant enzyme activity and reducing oxygen consumption and therefore free radical generation. Electron spin resonance measurements clearly demonstrate that disordering of mitochondrial lipid fluidity and membrane proteins mobility are the underlying contributors to this decreased oxygen consumption. Therefore, our results suggest that EMP might hold the potentiality to be developed as a non-invasive means to benefit certain diseases.
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NASA Astrophysics Data System (ADS)
Sathiyamoorthi, K.; Mala, V.; Sakthinathan, S. P.; Kamalakkannan, D.; Suresh, R.; Vanangamudi, G.; Thirunarayanan, G.
2013-08-01
Totally 38 aryl E 2-propen-1-ones including nine substituted styryl 4-iodophenyl ketones have been synthesised using solvent-free SiO2-H3PO4 catalyzed Aldol condensation between respective methyl ketones and substituted benzaldehydes under microwave irradiation. The yields of the ketones are more than 80%. The synthesised chalcones were characterized by their analytical, physical and spectroscopic data. The spectral frequencies of synthesised substituted styryl 4-iodophenyl ketones have been correlated with Hammett substituent constants, F and R parameters using single and multi-linear regression analysis. The antimicrobial activities of 4-iodophenyl chalcones have been studied using Bauer-Kirby method.
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The existence of a sticking region in free weight squats.
van den Tillaar, Roland; Andersen, Vidar; Saeterbakken, Atle Hole
2014-09-29
The aim of this study was to investigate the existence of the sticking region in two legged free weight squats. Fifteen resistance-training males (age 24 ± 4 years, body mass 82 ± 11 kg, body height 179 ± 6 cm) with 6 ± 3 years of resistance-training experience performed 6-RM in free weight squats. The last repetition was analyzed for the existence of a sticking region. Only in 10 out of 15 participants a sticking region was observed. The observed sticking region was much shorter than in the bench press. Furthermore, rectus femoris decreased the EMG activity in contrast to increased EMG activity in biceps femoris around the sticking and surrounding region. No significant change in EMG activity was found for the lateral and medial vastus muscles. It is suggested that a combination of these muscle activity changes could be one of the causes of the existence of the sticking region in free weight squats.
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The Existence of a Sticking Region in Free Weight Squats
van den Tillaar, Roland; Andersen, Vidar; Saeterbakken, Atle Hole
2014-01-01
The aim of this study was to investigate the existence of the sticking region in two legged free weight squats. Fifteen resistance-training males (age 24 ± 4 years, body mass 82 ± 11 kg, body height 179 ± 6 cm) with 6 ± 3 years of resistance-training experience performed 6-RM in free weight squats. The last repetition was analyzed for the existence of a sticking region. Only in 10 out of 15 participants a sticking region was observed. The observed sticking region was much shorter than in the bench press. Furthermore, rectus femoris decreased the EMG activity in contrast to increased EMG activity in biceps femoris around the sticking and surrounding region. No significant change in EMG activity was found for the lateral and medial vastus muscles. It is suggested that a combination of these muscle activity changes could be one of the causes of the existence of the sticking region in free weight squats. PMID:25414740
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Palaniraja, Jeyakannu; Mohana Roopan, Selvaraj; Mokesh Rayalu, G; Abdullah Al-Dhabi, Naif; Valan Arasu, Mariadhas
2016-11-18
This study deals with a new and efficient metal-free regioselective synthesis of pyrimido-fused indazoles with nitrogen ring junction motifs. We have developed a metal-free domino type reaction between 3-aminoindazole, aryl aldehydes and aceotophenones in the presence of KOH/DMF that leads to pyrimido[1,2- b ]indazole analogues. Response Surface Methodology (RSM) coupled with a Box-Behnken design (BBD) were utilized for exploring the effect of base used (A), temperature of reaction (B) and (C), reaction time. This approach can allow access to a variety of pyrimidoindazole fluorophores and related compounds. The compound N,N -dimethyl-4-(2-phenylpyrimido[1,2- b ]indazol-4-yl)aniline ( 4e ) displays the maximum fluorescence intensity at 518 nm and shows a fluorescence quantum yield of 0.068. The synthesized pyramido-fused indazoles have been evaluated for their free radical scavenging activity and compound 4f showed good antioxidant activity.
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ERIC Educational Resources Information Center
Wilson, Carrie; Garner, Barbara
1986-01-01
The Free Money Game is a group activity designed to: (1) familiarize refugee students with the purpose of public assistance, which is to maintain recipients at a survival level for a limited time; and (2) make students aware of the lack of options open to welfare recipients, the depersonalization associated with the bureaucracy, and the insecurity…
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ERIC Educational Resources Information Center
LeCrone, Nancy
2010-01-01
In high school students get tied up in extracurricular activities and have little time for pleasure reading. It is true that with rigorous academic schedules they have little time for pleasure reading. Thus began a conversation with a sophomore English teacher at the author's high school. As they were discussing the plight of free reading he was…
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Lipid metabolites with free-radical scavenging activity from Euphorbia helioscopia L.
Cateni, F; Zilic, J; Altieri, T; Zacchigna, M; Procida, G; Gaggeri, R; Rossi, D; Collina, S
2014-07-01
The methanolic extract of the plant Euphorbia helioscopia L. exhibited an interesting free-radical scavenging activity. From the aerial parts of Euphorbia helioscopia L. (Euphorbiaceae), a complex mixture of seven cerebrosides together with glucoclionasterol, a digalactosyldiacylglycerol and a diacylmonogalactosylglycerol were identified. The structures of the cerebrosides were characterized as 1-O-β-D-glucosides of phytosphingosines, which comprised (2S, 3S, 4E, 8E)-2-amino-4(E),8(E)-octadecadiene-1,3-diol, (2S, 3S, 4E, 8Z)-2-amino-4(E),8(Z)-octadecadiene-1,3-diol, (2S, 3S, 4R, 8Z)-2-amino-8(Z)-octadecene-1,3,4-triol as long chain bases with seven 2-hydroxy fatty acids of varying chain lengths (C16, C24:1, C26:1, C24, C26, C28:1) linked to the amino group. The glycosylglycerides were characterized as (2S)-2,3-O-di-(9,12,15-octadecatrienoyl)-glyceryl-6-O-(α-D-galactopyranosyl)-β-D-galactopyranoside and (2S)-2,3-O-di-(9,12,15-octadecatrienoyl)-glyceryl-1-O-β-D-galactopyranoside. The structures were established on the basis of spectroscopic data and chemical reactions. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
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Nguyen, Van Thi Ai; Le, Truong Dang; Phan, Hoa Ngoc; Tran, Lam Bich
2017-01-01
Free fatty acids (FFAs) were obtained from hydrolyzed virgin coconut oil (VCO) by Candida rugosa lipase (CRL). Four factors' influence on hydrolysis degree (HD) was examined. The best hydrolysis conditions in order to get the highest HD value were determined at VCO to buffer ratio 1 : 5 (w/w), CRL concentration 1.5% (w/w oil), pH 7, and temperature 40°C. After 16 hours' reaction, the HD value achieved 79.64%. FFAs and residual hydrolyzed virgin coconut oil (HVCO) were isolated from the hydrolysis products. They were tested for their antibacterial activity against Gram-negative and Gram-positive bacteria, which can be found in contaminated food and cause food poisoning. FFAs showed their inhibition against Bacillus subtilis (ATCC 11774), Escherichia coli (ATCC 25922), Salmonella enteritidis (ATCC 13076), and Staphylococcus aureus (ATCC 25923) at minimum inhibitory concentration (MIC) of 50%, 60%, 20%, and 40%, respectively. However, VCO and HVCO did not show their antibacterial activity against these tested bacteria.
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Phan, Hoa Ngoc; Tran, Lam Bich
2017-01-01
Free fatty acids (FFAs) were obtained from hydrolyzed virgin coconut oil (VCO) by Candida rugosa lipase (CRL). Four factors' influence on hydrolysis degree (HD) was examined. The best hydrolysis conditions in order to get the highest HD value were determined at VCO to buffer ratio 1 : 5 (w/w), CRL concentration 1.5% (w/w oil), pH 7, and temperature 40°C. After 16 hours' reaction, the HD value achieved 79.64%. FFAs and residual hydrolyzed virgin coconut oil (HVCO) were isolated from the hydrolysis products. They were tested for their antibacterial activity against Gram-negative and Gram-positive bacteria, which can be found in contaminated food and cause food poisoning. FFAs showed their inhibition against Bacillus subtilis (ATCC 11774), Escherichia coli (ATCC 25922), Salmonella enteritidis (ATCC 13076), and Staphylococcus aureus (ATCC 25923) at minimum inhibitory concentration (MIC) of 50%, 60%, 20%, and 40%, respectively. However, VCO and HVCO did not show their antibacterial activity against these tested bacteria. PMID:29259829
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A robust active control system for shimmy damping in the presence of free play and uncertainties
NASA Astrophysics Data System (ADS)
Orlando, Calogero; Alaimo, Andrea
2017-02-01
Shimmy vibration is the oscillatory motion of the fork-wheel assembly about the steering axis. It represents one of the major problem of aircraft landing gear because it can lead to excessive wear, discomfort as well as safety concerns. Based on the nonlinear model of the mechanics of a single wheel nose landing gear (NLG), electromechanical actuator and tire elasticity, a robust active controller capable of damping shimmy vibration is designed and investigated in this study. A novel Decline Population Swarm Optimization (PDSO) procedure is introduced and used to select the optimal parameters for the controller. The PDSO procedure is based on a decline demographic model and shows high global search capability with reduced computational costs. The open and closed loop system behavior is analyzed under different case studies of aeronautical interest and the effects of torsional free play on the nose landing gear response are also studied. Plant parameters probabilistic uncertainties are then taken into account to assess the active controller robustness using a stochastic approach.
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Failure of policy regarding smoke-free bars in the Netherlands.
Gonzalez, Mariaelena; Glantz, Stanton A
2013-02-01
Tobacco companies consistently work to prevent and undermine smoke-free laws. The tobacco industry and its allies have funded hospitality associations and other third parties to oppose smoke-free laws, argue that smoke-free laws will economically damage hospitality venues, promote ventilation and voluntary smoker 'accommodation' as an alternative to smoke-free laws, and to challenge smoke-free laws in court. In 2008, the Netherlands extended its smoke-free law to hospitality venues. We triangulated news articles, government documents, scientific papers, statistical reports and interviews to construct this case study. Despite widespread public support for smoke-free hospitality venues, opponents successfully represented these laws as unpopular and damaging to small bars. These challenges and related smokers' rights activities resulted in non-compliance among all bars and reinstating an exemption for small, owner-run venues. This policy reversal was the result of a weak implementing media campaign (which failed to present the law as protecting nonsmokers), smoking room exemptions and reactive (vs. proactive) measures by the Ministry of Health and civil society. The policy failure in the Netherlands is the result of poor implementation efforts and the failure to anticipate and deal with opposition to the law. When implementing smoke-free laws it is important to anticipate opposition, used the media to target non-smokers to reinforce public support, and actively enforce the law.
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Failure of policy regarding smoke-free bars in the Netherlands*
Gonzalez, Mariaelena
2013-01-01
Background: Tobacco companies consistently work to prevent and undermine smoke-free laws. The tobacco industry and its allies have funded hospitality associations and other third parties to oppose smoke-free laws, argue that smoke-free laws will economically damage hospitality venues, promote ventilation and voluntary smoker ‘accommodation’ as an alternative to smoke-free laws, and to challenge smoke-free laws in court. In 2008, the Netherlands extended its smoke-free law to hospitality venues. Methods: We triangulated news articles, government documents, scientific papers, statistical reports and interviews to construct this case study. Results: Despite widespread public support for smoke-free hospitality venues, opponents successfully represented these laws as unpopular and damaging to small bars. These challenges and related smokers’ rights activities resulted in non-compliance among all bars and reinstating an exemption for small, owner-run venues. This policy reversal was the result of a weak implementing media campaign (which failed to present the law as protecting nonsmokers), smoking room exemptions and reactive (vs. proactive) measures by the Ministry of Health and civil society. Conclusion: The policy failure in the Netherlands is the result of poor implementation efforts and the failure to anticipate and deal with opposition to the law. When implementing smoke-free laws it is important to anticipate opposition, used the media to target non-smokers to reinforce public support, and actively enforce the law. PMID:22143826
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Farahani, H.; Hasan, M.
1992-02-01
The biochemical response to controlled inhalation of nitrogen dioxide (NO2) was studied in 18 male guinea pigs. Animals were exposed to 2.5, 5.0, and 10 ppm NO2 for 2h daily for 35 consecutive days, and the results compared with six control animals exposed to filtered air for 2h daily for same period. Five biochemical parameters, including triglyceride, free fatty acids, esterified fatty acid, ganglioside and lipase activity were measured immediately after the last day of exposure. At 2.5 ppm NO2 inhalation no significant changes occurred in any region of the central nervous system (CNS). While as the dose concentration wasmore » increased to 5 and 10 ppm nitrogen dioxide, significant dose-related alteration were observed in the levels of triglyceride, free fatty acid, esterified fatty acid, ganglioside and lipase activity in the different regions of the guinea pig CNS.« less
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Jia, Zhenzhen; Feng, Zeyang; Wang, Lining; Li, Hao; Wang, Hongyu; Xu, Dingqi; Zhao, Xin; Feng, Daofu; Feng, Xizeng
2018-05-23
Reproductive dysfunction associated with obesity is increasing among women of reproductive age, including infertility and increasing risk of miscarriage. In females, reproductive disorders are linked to declining quality of oocytes. Using a model of diet-induced obesity, we have investigated the possible effects of obesity on oocyte quality, including metabolism, lipid accumulation, ROS levels, meiosis and changes in spindle structure in Metaphase II. Our study showed that obesity induced by a high fat diet can impair oocyte meiosis, destroy spindle assembly, and promote oxidative stress and abnormal mitochondrial distribution. With the addition of resveratrol, the negative impact of diet-induced obesity on the quality of oocytes was alleviated to some extent. In addition, we found that obesity causes mouse oocytes to soften, and resveratrol can restore the zona pellucida of oocytes to the same state as the control group. In conclusion, resveratrol can reverse the adverse effects of obesity on oocytes, which is beneficial for subsequent embryonic development.
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Friebe, Andrea; Evans, Alina L; Arnemo, Jon M; Blanc, Stéphane; Brunberg, Sven; Fleissner, Günther; Swenson, Jon E; Zedrosser, Andreas
2014-01-01
Knowledge of factors influencing the timing of reproduction is important for animal conservation and management. Brown bears (Ursus arctos) are able to vary the birth date of their cubs in response to their fat stores, but little information is available about the timing of implantation and parturition in free-ranging brown bears. Body temperature and activity of pregnant brown bears is higher during the gestation period than during the rest of hibernation and drops at parturition. We compared mean daily body temperature and activity levels of pregnant and nonpregnant females during preimplantation, gestation, and lactation. Additionally we tested whether age, litter size, primiparity, environmental conditions, and the start of hibernation influence the timing of parturition. The mean date of implantation was 1 December (SD = 12), the mean date of parturition was 26 January (SD = 12), and the mean duration of the gestation period was 56 days (SD = 2). The body temperature of pregnant females was higher during the gestation and lactation periods than that of nonpregnant bears. The body temperature of pregnant females decreased during the gestation period. Activity recordings were also used to determine the date of parturition. The parturition dates calculated with activity and body temperature data did not differ significantly and were the same in 50% of the females. Older females started hibernation earlier. The start of hibernation was earlier during years with favorable environmental conditions. Dates of parturition were later during years with good environmental conditions which was unexpected. We suggest that free-ranging pregnant brown bears in areas with high levels of human activities at the beginning of the denning period, as in our study area, might prioritize investing energy in early denning than in early parturition during years with favorable environmental conditions, as a strategy to prevent disturbances caused by human.
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Friebe, Andrea; Evans, Alina L.; Arnemo, Jon M.; Blanc, Stéphane; Brunberg, Sven; Fleissner, Günther; Swenson, Jon E.; Zedrosser, Andreas
2014-01-01
Knowledge of factors influencing the timing of reproduction is important for animal conservation and management. Brown bears (Ursus arctos) are able to vary the birth date of their cubs in response to their fat stores, but little information is available about the timing of implantation and parturition in free-ranging brown bears. Body temperature and activity of pregnant brown bears is higher during the gestation period than during the rest of hibernation and drops at parturition. We compared mean daily body temperature and activity levels of pregnant and nonpregnant females during preimplantation, gestation, and lactation. Additionally we tested whether age, litter size, primiparity, environmental conditions, and the start of hibernation influence the timing of parturition. The mean date of implantation was 1 December (SD = 12), the mean date of parturition was 26 January (SD = 12), and the mean duration of the gestation period was 56 days (SD = 2). The body temperature of pregnant females was higher during the gestation and lactation periods than that of nonpregnant bears. The body temperature of pregnant females decreased during the gestation period. Activity recordings were also used to determine the date of parturition. The parturition dates calculated with activity and body temperature data did not differ significantly and were the same in 50% of the females. Older females started hibernation earlier. The start of hibernation was earlier during years with favorable environmental conditions. Dates of parturition were later during years with good environmental conditions which was unexpected. We suggest that free-ranging pregnant brown bears in areas with high levels of human activities at the beginning of the denning period, as in our study area, might prioritize investing energy in early denning than in early parturition during years with favorable environmental conditions, as a strategy to prevent disturbances caused by human. PMID:24988486
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García-Altés, Anna; Pinilla, Jaime; Marí-Dell'Olmo, Marc; Fernández, Esteve; López, Maria José
2015-11-01
The potential of smoke-free bans to negatively impact the hospitality business has been an argument of the hospitality and tobacco industry against such legislation. A partial smoke-free legislation was introduced in Spain in 2006 allowing smoking in most bars and restaurants due to the pressure of the hospitality sector. However, this partial ban was later amended in 2011 to include all the hospitality premises without exceptions. The stepped Spanish process permits to evaluate whether the entry into force of the smoke-free legislation had any effect on the economic activity of the hospitality sector. We employed a pooled time series cross-sectional design, with national data over 6 years (2006-2011). The dependent variable used was the total number of bars and restaurants per 100,000 inhabitants. The explanatory variables used were the average amount of spending per household in bars and restaurants, and the total unemployment rate in Spain by regions. For every 1% increase in the unemployment rate there was a 0.05% decrease in the number of bars and restaurants. In 2007, the number of bars and restaurants was significantly reduced by 13.06% (all others factors being held constant), 4.87% in 2008, and 10.42% in 2009. No statistically significant effect of the smoke-free legislation emerged from 2010 (6.76%) to 2011 (7.69%). The new Spanish smoke-free legislation had no effect on the number of bars and restaurants. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
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Serendipitous findings while researching oxygen free radicals.
Floyd, Robert A
2009-04-15
This review is based on the honor of receiving the Discovery Award from the Society of Free Radical Biology and Medicine. The review is reflective and presents our thinking that led to experiments that yielded novel observations. Critical questioning of our understanding of oxygen free radicals in biomedical problems led us to use and develop more direct and extremely sensitive methods. This included nitrone free radical spin trapping and HPLC-electrochemical detection. This technology led to the pioneering use of salicylate to trap hydroxyl free radicals and show increased flux in ischemia/reperfused brain regions and also to first sensitively detect 8-hydroxyl-2-deoxyguanosine in oxidatively damaged DNA and help assess its role in cancer development. We demonstrated that methylene blue (MB) photoinduces formation of 8-hydroxyguanine in DNA and RNA and discovered that MB sensitively photoinactivates RNA viruses, including HIV and the West Nile virus. Studies in experimental stroke led us serendipitously to discover that alpha-phenyl-tert-butylnitrone (PBN) was neuroprotective if given after the stroke. This led to extensive commercial development of NXY-059, a PBN derivative, for the treatment of stroke. More recently we discovered that PBN nitrones have potent anti-cancer activity and are active in preventing hearing loss caused by acute acoustical trauma.
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Quast, Robert B.; Sonnabend, Andrei; Stech, Marlitt; Wüstenhagen, Doreen A.; Kubick, Stefan
2016-01-01
Cell-free protein synthesis systems derived from eukaryotic sources often provide comparatively low amounts of several μg per ml of de novo synthesized membrane protein. In order to overcome this, we herein demonstrate the high-yield cell-free synthesis of the human EGFR in a microsome-containing system derived from cultured Sf21 cells. Yields were increased more than 100-fold to more than 285 μg/ml by combination of IRES-mediated protein translation with a continuous exchange cell-free reaction format that allowed for prolonged reaction lifetimes exceeding 24 hours. In addition, an orthogonal cell-free translation system is presented that enabled the site-directed incorporation of p-Azido-L-phenylalanine by amber suppression. Functionality of cell-free synthesized receptor molecules is demonstrated by investigation of autophosphorylation activity in the absence of ligand and interaction with the cell-free synthesized adapter molecule Grb2. PMID:27456041
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Compound cuing in free recall.
Lohnas, Lynn J; Kahana, Michael J
2014-01-01
According to the retrieved context theory of episodic memory, the cue for recall of an item is a weighted sum of recently activated cognitive states, including previously recalled and studied items as well as their associations. We show that this theory predicts there should be compound cuing in free recall. Specifically, the temporal contiguity effect should be greater when the 2 most recently recalled items were studied in contiguous list positions. A meta-analysis of published free recall experiments demonstrates evidence for compound cuing in both conditional response probabilities and interresponse times. To help rule out a rehearsal-based account of these compound cuing effects, we conducted an experiment with immediate, delayed, and continual-distractor free recall conditions. Consistent with retrieved context theory but not with a rehearsal-based account, compound cuing was present in all conditions, and was not significantly influenced by the presence of interitem distractors.
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Compound cueing in free recall
Lohnas, Lynn J.; Kahana, Michael J.
2013-01-01
According to the retrieved context theory of episodic memory, the cue for recall of an item is a weighted sum of recently activated cognitive states, including previously recalled and studied items as well as their associations. We show that this theory predicts there should be compound cueing in free recall. Specifically, the temporal contiguity effect should be greater when the two most recently recalled items were studied in contiguous list positions. A meta-analysis of published free recall experiments demonstrates evidence for compound cueing in both conditional response probabilities and inter-response times. To help rule out a rehearsal-based account of these compound cueing effects, we conducted an experiment with immediate, delayed and continual-distractor free recall conditions. Consistent with retrieved context theory but not with a rehearsal-based account, compound cueing was present in all conditions, and was not significantly influenced by the presence of interitem distractors. PMID:23957364
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Watch Out for the "Living Dead": Cell-Free Enzymes and Their Fate.
Baltar, Federico
2017-01-01
Microbes are the engines driving biogeochemical cycles. Microbial extracellular enzymatic activities (EEAs) are the "gatekeepers" of the carbon cycle. The total EEA is the sum of cell-bound (i.e., cell-attached), and dissolved (i.e., cell-free) enzyme activities. Cell-free enzymes make up a substantial proportion (up to 100%) of the total marine EEA. Although we are learning more about how microbial diversity and function (including total EEA) will be affected by environmental changes, little is known about what factors control the importance of the abundant cell-free enzymes. Since cell-attached EEAs are linked to the cell, their fate will likely be linked to the factors controlling the cell's fate. In contrast, cell-free enzymes belong to a kind of "living dead" realm because they are not attached to a living cell but still are able to perform their function away from the cell; and as such, the factors controlling their activity and fate might differ from those affecting cell-attached enzymes. This article aims to place cell-free EEA into the wider context of hydrolysis of organic matter, deal with recent studies assessing what controls the production, activity and lifetime of cell-free EEA, and what their fate might be in response to environmental stressors. This perspective article advocates the need to go "beyond the living things," studying the response of cells/organisms to different stressors, but also to study cell-free enzymes, in order to fully constrain the future and evolution of marine biogeochemical cycles.
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Sarkar, Debjani; Kundu, Sunanda; De, Soumita; Hariharan, Chellaram; Saha, Piu; Manna, Alak; Chattopadhyay, Subrata; Chatterjee, Mitali
2013-03-01
Allylpyrocatechol (APC) is responsible for the antiinflammatory activity exhibited by the methanolic extract of leaves of Piper betle. As antiinflammatory compounds may display antioxidant properties and vice versa, we investigated the antioxidant effect of APC. APC effectively reduced phorbol-myristate-acetate-induced generation of reactive oxygen species and superoxide in murine peritoneal macrophages as well as inhibited Escherichia-coli-induced phagocytic activity of macrophages. Furthermore, pBluescript SK(+) plasmid DNA damage induced by addition of sodium ascorbate was attenuated by APC as it inhibited transformation of the supercoiled form to a relaxed form. In addition, APC increased the enzymatic (catalase) and nonenzymatic (GSH) antioxidant components of murine macrophages. Taken together, APC exhibited an antioxidant activity which was mediated both via decreased generation of free radicals along with increase in cellular antioxidants. Copyright © 2012 John Wiley & Sons, Ltd.
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Konovalova, G G; Lankin, V Z; Tikhaze, A K; Nezhdanova, I B; Lisina, M O; Kukharchuk, V V
2003-08-01
We studied the effect of a complex containing antioxidant vitamins C and E, provitamin A, and antioxidant element selenium on the contents of primary (lipid peroxides) and secondary products (malonic dialdehyde) of free radical lipid oxidation in low-density lipoproteins isolated from the plasma of patients with coronary heart disease and hypercholesterolemia by means of preparative ultracentrifugation. Activity of key antioxidant enzymes in the blood was measured during treatment with the antioxidant preparation. Combination treatment with antioxidant vitamins and antioxidant element selenium sharply decreased the contents of primary and secondary free radical oxidation products in circulating low-density lipoproteins and increased activity of antioxidant enzymes in erythrocytes. Activities of superoxide dismutase and selenium-containing glutathione peroxidase increased 1 and 2 months after the start of therapy, respectively.
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Calasso, Maria; Mancini, Leonardo; Di Cagno, Raffaella; Cardinali, Gianluigi; Gobbetti, Marco
2015-09-01
Freeze-dried cell-free extracts (CFE) from Lactobacillus casei LC01, Weissella cibaria 1XF5, Hafnia alvei Moller ATCC 51815, and Debaryomyces hansenii LCF-558 were used as sources of enzyme activities for conditioning the ripening of ewe milk cheese. Compared with control cheese (CC), CFE did not affect the gross composition and the growth of the main microbial groups of the cheeses. As shown through urea-PAGE electrophoresis of the pH 4.6-soluble nitrogen fraction and the analysis of free AA, the secondary proteolysis of the cheeses with CFE added was markedly differed from that of the CC. Compared with CC, several enzyme activities were higher in the water-soluble extracts from cheeses made with CFE. In agreement, the levels of 49 volatile compounds significantly differentiated CC from the cheeses made with CFE. The level of some alcohols, ketones, sulfur compounds, and furans were the lowest in the CC, whereas most aldehydes were the highest. Each CFE seemed to affect a specific class of chemical compounds (e.g., the CFE from H. alvei ATCC 51815 mainly influenced the synthesis of sulfur compounds). Apart from the microbial source used, the cheeses with the addition of CFE showed higher score for acceptability than the control cheese. Cheese ripening was accelerated or conditioned using CFE as sources of tailored enzyme activities. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
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Valletta, John Joseph; Chipperfield, Andrew J; Byrne, Christopher D
2009-01-01
Good blood glucose control is important to people with type 1 diabetes to prevent diabetes-related complications. Too much blood glucose (hyperglycaemia) causes long-term micro-vascular complications, while a severe drop in blood glucose (hypoglycaemia) can cause life-threatening coma. Finding the right balance between quantity and type of food intake, physical activity levels and insulin dosage, is a daily challenge. Increased physical activity levels often cause changes in blood glucose due to increased glucose uptake into tissues such as muscle. To date we have limited knowledge about the minute by minute effects of exercise on blood glucose levels, in part due to the difficulty in measuring glucose and physical activity levels continuously, in a free-living environment. By using a light and user-friendly armband we can record physical activity energy expenditure on a minute-by-minute basis. Simultaneously, by using a continuous glucose monitoring system we can record glucose concentrations. In this paper, Gaussian Processes are used to model the glucose excursions in response to physical activity data, to study its effect on glycaemic control.
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Cortical Entropy, Mutual Information and Scale-Free Dynamics in Waking Mice.
Fagerholm, Erik D; Scott, Gregory; Shew, Woodrow L; Song, Chenchen; Leech, Robert; Knöpfel, Thomas; Sharp, David J
2016-10-01
Some neural circuits operate with simple dynamics characterized by one or a few well-defined spatiotemporal scales (e.g. central pattern generators). In contrast, cortical neuronal networks often exhibit richer activity patterns in which all spatiotemporal scales are represented. Such "scale-free" cortical dynamics manifest as cascades of activity with cascade sizes that are distributed according to a power-law. Theory and in vitro experiments suggest that information transmission among cortical circuits is optimized by scale-free dynamics. In vivo tests of this hypothesis have been limited by experimental techniques with insufficient spatial coverage and resolution, i.e., restricted access to a wide range of scales. We overcame these limitations by using genetically encoded voltage imaging to track neural activity in layer 2/3 pyramidal cells across the cortex in mice. As mice recovered from anesthesia, we observed three changes: (a) cortical information capacity increased, (b) information transmission among cortical regions increased and (c) neural activity became scale-free. Our results demonstrate that both information capacity and information transmission are maximized in the awake state in cortical regions with scale-free network dynamics. © The Author 2016. Published by Oxford University Press.
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Hong, Qingshui; Lu, Huimin
2017-06-13
Carbon fiber papers supported Ag catalysts (Ag/CFP) with different coverage of electro-active site are prepared by electrochemical deposition and used as binder free cathodes in primary aluminum-air (Al-air) battery. Scanning Electron Microscopy and X-ray Diffraction studies are carried out to characterize the as-prepared Ag/CFP air cathodes. Oxygen reduction reaction (ORR) activities on these air cathodes in alkaline solutions are systematic studied. A newly designed aluminum-air cell is used to further determine the cathodes performance under real operation condition and during the test, the Ag/CFP electrodes show outstanding catalytic activity for ORR in concentrated alkaline electrolyte, and no obvious activity degradation is observed after long-time discharge. The electrochemical test results display the dependence of coverage of the electro-active Ag on the catalytic performance of the air cathodes. The resulting primary Al-air battery made from the best-performing cathode shows an impressive discharge peak power density, outperforming that of using commercial nano-manganese catalyst air electrodes.
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Sonboli, Ali; Mojarrad, Mehran; Nejad Ebrahimi, Samad; Enayat, Shabnam
2010-01-01
This study was designed to examine the in vitro antioxidant activities and total phenolic contents of the methanolic extracts from male inflorescence of Salix aegyptiaca L. grown in Iran. The methanolic extract (ME) and its three fractions including water (WF), butanol (BF) and chloroform (CF) were prepared and then their antioxidant activities, as well as total phenolic contents, were evaluated by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and the Folin–Ciocalteu method, respectively. Among the different fractions of methanol extract, BF indicated the most antioxidant activity with an IC50 value of 27.7 μg/mL and total phenols of 313.8 ppm, which is comparable with the synthetic antioxidant BHT (IC50 = 26.5μg/mL). The antioxidant activities of the other fractions decreased in the order of ME >WF > CF. The potent antioxidant activity of S. aegyptiaca supported its possible use as a natural antioxidant in food industries and other pharmaceutical preparations. PMID:24363740
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Control of free-flying space robot manipulator systems
NASA Technical Reports Server (NTRS)
Cannon, Robert H., Jr.
1990-01-01
New control techniques for self contained, autonomous free flying space robots were developed and tested experimentally. Free flying robots are envisioned as a key element of any successful long term presence in space. These robots must be capable of performing the assembly, maintenance, and inspection, and repair tasks that currently require human extravehicular activity (EVA). A set of research projects were developed and carried out using lab models of satellite robots and a flexible manipulator. The second generation space robot models use air cushion vehicle (ACV) technology to simulate in 2-D the drag free, zero g conditions of space. The current work is divided into 5 major projects: Global Navigation and Control of a Free Floating Robot, Cooperative Manipulation from a Free Flying Robot, Multiple Robot Cooperation, Thrusterless Robotic Locomotion, and Dynamic Payload Manipulation. These projects are examined in detail.
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[Study of scavenging activity of sorghum pigment to hydroxyl free radicals by fluorimetry].
Zhang, Hai-rong; Wang, Wen-yan
2007-03-01
A natural product, sorghum pigment, consists of a number of important flavonoid derivatives, occurrs on the seed capsules or in the stems of many sorghums, and is widely applied in different fields of food, cosmetic and dyeing industries, It is important for scavenging hydroxyl free radicals and protection of human healthiness. Scavenging capacities of hydroxyl free radicals with sodium nitrite, quercetin and sorghum pigment were comparatively researched by fluorimetry, and the model of hydroxyl free radicals produced is based on the reaction of Cu2+ -catalyzed oxidation of ascorbic acid in the presence of hydrogen peroxide. The hydroxyl radicals react with benzoic acid, forming a fluorescent product, and the fluorescence intensity was determined by the concentration of hydroxybenzoic acid. The experimental results show that the sodium nitrite, quercetin and sorghum pigment have a quantity-effect relationship for scavenging hydroxyl free radicals, and sodium nitrite and quercetin in comparison with sorghum pigment have high antioxidant capacity. Finally, the quenching mechanisms were explored with sodium nitrite, sorghum pigment, and quercetin respectively. The sorghum pigment and sodium nitrite feature a dynamic quenching processes, while quercetin shows a static quenching processes. A reference method was provided for reasonable exploitation and utilization of sorghum pigment.
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Preliminary studies on the activities of spin traps as scavengers of free radicals
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ogunbiyi, P.O.; Washington, I.
1991-03-15
The spin trapping agents, N-t-Butyl-a-phenyl-nitrone (PBN) and 5,5-Dimethyl-1-pyroline-N-oxide (DMPO) have been used to investigate the primary free radicals involved in various tissue injuries. Also, PBN and DMPO can provide some protection against free radical-induced lung injuries. However, their therapeutic potentials as free radical scavengers remained unexamined. In this study, the effects of PBN and DMPO on guinea pig lung microsomal lipid peroxidation were investigated using thiobarbituric acid-reactive substance assay. Superoxide anions (O{sup 2}{minus}) were generated in an enzymatic and a non-enzymatic system. PBN and DMPO each, significantly inhibited NADPH-stimulated lipid peroxidation irrespective of the presence of Fe{sup 3+}. Cytochrome cmore » reduction by the enzymatic and nitro blue tetrazolium reduction by the non-enzymatic O{sup 2}{minus} generating systems were both inhibited by PBN and DMPO as well as superoxide dismutase and dimethyl sulfoxide when compared with the controls. The spin traps exhibited lower potencies in these systems than the reference compounds, SOD and DMSO, which are well established as O{sup 2}{minus} and hydroxyl radical scavengers respectively. Results demonstrate the free radical scavenging properties of PBN and DMPO. This is an indication of their possible usefulness as antioxidants.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Lau, Aik Jiang; Chang, Thomas K.H., E-mail: thomas.chang@ubc.ca
The naturally occurring SV23 splice variant of human constitutive androstane receptor (hCAR-SV23) is activated by di-(2-ethylhexyl)phthalate (DEHP), which is detected as a contaminant in fetal bovine serum (FBS). In our initial experiment, we compared the effect of dialyzed FBS, charcoal-stripped, dextran-treated FBS (CS-FBS), and regular FBS on the basal activity and ligand-activation of hCAR-SV23 in a cell-based reporter gene assay. In transfected HepG2 cells cultured in medium supplemented with 10% FBS, basal hCAR-SV23 activity varied with the type of FBS (regular > dialyzed > CS). DEHP increased hCAR-SV23 activity when 10% CS-FBS, but not regular FBS or dialyzed FBS, wasmore » used. With increasing concentrations (1–10%) of regular FBS or CS-FBS, hCAR-SV23 basal activity increased, whereas in DEHP-treated cells, hCAR-SV23 activity remained similar (regular FBS) or slightly increased (CS-FBS). Subsequent experiments identified a serum-free culture condition to detect DEHP activation of hCAR-SV23. Under this condition, artemisinin, artemether, and arteether increased hCAR-SV23 activity, whereas they decreased it in cells cultured in medium supplemented with 10% regular FBS. By comparison, FBS increased the basal activity of the wild-type isoform of hCAR (hCAR-WT), whereas it did not affect the basal activity of the SV24 splice variant (hCAR-SV24) or ligand activation of hCAR-SV24 and hCAR-WT by 6-(4-chlorophenyl)imidazo[2,1-b][1,3]thiazole-5-carbaldehyde O-(3,4-dichlorobenzyl)oxime (CITCO). The use of serum-free culture condition was suitable for detecting CITCO activation of hCAR-WT and hCAR-SV24. In conclusion, FBS leads to erroneous classification of pharmacological ligands of hCAR-SV23 in cell-based assays, but investigations on functional ligands of hCAR isoforms can be conducted in serum-free culture condition. - Highlights: • FBS leads to erroneous pharmacological classification of hCAR-SV23 ligands. • Artemisinin, artemether, and arteether
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NASA Astrophysics Data System (ADS)
Hamid, Noor Huda Abd; Latip, Jalifah; Markom, Masturah
2018-04-01
Marantodes pumila is one of the important herbs used in traditional medicine. However, there is no report on the optimum method for the preparation of M. pumila extract enriched with bioactive compounds. Therefore, this study aim to establish the suitable method in the preparation of M. pumila extracts enriched with antioxidative compounds. Different conventional extraction methods such as maceration, reflux and Soxhlet in solvents of different polarities i.e. ethanol, 50 % aqueous ethanol and water were employed to prepare extracts. Constituents of each extract were profiled using RP-HPLC followed by the free radical scavenging assay using 2,2 diphenyl-1-picrylhydrazyl (DPPH) to determine the antioxidant activity. Among all extraction methods, maceration in 50 % aqueous ethanol gave the highest total percentage yield (22.41 %) while all extraction methods were able to extract the marker compounds, gallic acid (GA) and methyl gallate (MGA). The free radical scavenging activity of extracts varied from IC50 11.93 µg/mL (50 % aqueous ethanol via reflux) to 64.15 µg/mL (water via maceration). All extracts showed better scavenging activity as compared to synthetic antioxidant, BHT. The variation in the IC50 values is expected due to the presence of different types and/or concentration of bioactive compounds in each extract. This study may provide a preliminary insight for the preparation of standardized extracts of M. pumila enriched with bioactive compounds.
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Solution structural ensembles of substrate-free cytochrome P450(cam).
Asciutto, Eliana K; Young, Matthew J; Madura, Jeffry; Pochapsky, Susan Sondej; Pochapsky, Thomas C
2012-04-24
Removal of substrate (+)-camphor from the active site of cytochrome P450(cam) (CYP101A1) results in nuclear magnetic resonance-detected perturbations in multiple regions of the enzyme. The (1)H-(15)N correlation map of substrate-free diamagnetic Fe(II) CO-bound CYP101A permits these perturbations to be mapped onto the solution structure of the enzyme. Residual dipolar couplings (RDCs) were measured for (15)N-(1)H amide pairs in two independent alignment media for the substrate-free enzyme and used as restraints in solvated molecular dynamics (MD) simulations to generate an ensemble of best-fit structures of the substrate-free enzyme in solution. Nuclear magnetic resonance-detected chemical shift perturbations reflect changes in the electronic environment of the NH pairs, such as hydrogen bonding and ring current shifts, and are observed for residues in the active site as well as in hinge regions between secondary structural features. RDCs provide information about relative orientations of secondary structures, and RDC-restrained MD simulations indicate that portions of a β-rich region adjacent to the active site shift so as to partially occupy the vacancy left by removal of the substrate. The accessible volume of the active site is reduced in the substrate-free enzyme relative to the substrate-bound structure calculated using the same methods. Both symmetric and asymmetric broadening of multiple resonances observed upon substrate removal as well as localized increased errors in RDC fits suggest that an ensemble of enzyme conformations are present in the substrate-free form.
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Studies on residue-free decontaminants for chemical warfare agents.
Wagner, George W
2015-03-17
Residue-free decontaminants based on hydrogen peroxide, which decomposes to water and oxygen in the environment, are examined as decontaminants for chemical warfare agents (CWA). For the apparent special case of CWA on concrete, H2O2 alone, without any additives, effectively decontaminates S-2-(diisopropylamino)ethyl O-ethyl methylphosphonothioate (VX), pinacolyl methylphosphorofluoridate (GD), and bis(2-choroethyl) sulfide (HD) in a process thought to involve H2O2 activation by surface-bound carbonates/bicarbonates (known H2O2 activators for CWA decontamination). A plethora of products are formed during the H2O2 decontamination of HD on concrete, and these are characterized by comparison to synthesized authentic compounds. As a potential residue-free decontaminant for surfaces other than concrete (or those lacking adsorbed carbonate/bicarbonate) H2O2 activation for CWA decontamination is feasible using residue-free NH3 and CO2 as demonstrated by reaction studies for VX, GD, and HD in homogeneous solution. Although H2O2/NH3/CO2 ("HPAC") decontaminants are active for CWA decontamination in solution, they require testing on actual surfaces of interest to assess their true efficacy for surface decontamination.
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Santos, R R M; Cavallari, M M; Pimenta, M A S; Abreu, A G; Costa, M R; Guedes, M L
2015-06-11
Attalea vitrivir Zona (synonym Orbignya oleifera) is one of the six species of Arecaceae known as "babassu". This species is used to make cosmetics, food, and detergents due to the high concentration of oil in the seeds. It is found only in fragmented areas of southern Bahia State and northern Minas Gerais State, southeast Brazil, and this fragmentation has affected both its ecological and genetic characteristics. We evaluated the genetic diversity and population genetic structure of A. vitrivir in six areas of two different regions at the extremes of its geographical range, in order to gain a better understanding of the factors that affect the distribution and partitioning of its diversity. Nine inter simple sequence repeat (ISSR) markers amplified 74 polymorphic bands, resulting in large diversity values (Shannon diversity index, 0.37-0.47; intrapopulation genetic diversity, 0.25-0.34). Analysis of molecular variance (AMOVA) revealed considerable differentiation between sampling sites (30.03%) and regions (12.08%), although most of the diversity was observed within sampling sites (69%). Further differentiation between sampling sites was noted more in the northern region than in the southern region, highlighting the genetic connectivity between the sampling sites within Rio Pandeiros Environmental Protection Area (southern region). The identification of two distinct genetic clusters (K = 2) corresponded to the northern and southern regions, and corroborated the AMOVA results. We suggest that the northern area, outside Rio Pandeiros Environmental Protection Area, must be included in future management plans for this species.
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Foaling rates in feral horses treated with the immunocontraceptive porcine zona pellucida
Ransom, J.I.; Roelle, J.E.; Cade, B.S.; Coates-Markle, L.; Kane, A.J.
2011-01-01
Locally abundant feral horses (Equus caballus) can rapidly deplete available resources. Fertility control agents present promising nonlethal tools for reducing their population growth rates. We tested the effect of 2 forms of the immunocontraceptive porcine zona pellucida (PZP) on foaling rates in 3 populations of feral horses in the western United States. A liquid form requiring annual boosters was administered at Little Book Cliffs Wild Horse Range, Mesa County (CO), and Pryor Mountain Wild Horse Range, Bighorn County (WY) and Carbon County (MT), and a time-release pellet form designed to produce 2 yr of infertility was administered at McCullough Peaks Herd Management Area, Park County (WY). Average foaling rates (foals born/mare-yr) from direct observation of untreated and treated female horses (mares), 2004-2008, were 60.1% (n = 153 mare-yr) versus 6.6% (n = 91 mare-yr) at Little Book Cliffs, and 62.8% (n = 129 mare-yr) versus 17.7% (n = 79 mare-yr) at Pryor Mountain, respectively. At McCullough Peaks, mean annual foaling rates from 2006 to 2008 were 75.0% (n = 48 mare-yr) for untreated mares and 31.7% (n = 101 mare-yr) for treated mares. Controlling for age of mares and pretreatment differences in fertility, PZP reduced foaling rates in all 3 herds. The pellets used at McCullough Peaks (produced by cold evaporation) were less effective than pellets used in a previous trial and produced by heat extrusion. Immunocontraception with PZP may be a useful tool in reducing fertility rates in some western United States feral horse herds, but population growth reduction will depend on timely access to mares for inoculation and the proportion of mares that can be successfully treated. ?? 2011 The Wildlife Society.
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Vahidy, Wajiha H; Ong, Wei-Yi; Farooqui, Akhlaq A; Yeo, Jin-Fei
2006-10-01
The present study was carried out to determine the effects of central nervous free fatty acids, lysophospholipids, or platelet activating factor (PAF), in a mouse facial carrageenan injection model of orofacial pain. Mice that received intracerebroventricular (I.C.V.) injection of arachidonic acid or oleic acid showed significantly reduced allodynia and behavioral responses to von Frey hair stimulation of a carrageenan-injected area of the face, at 8 h post-injection, compared to controls that received I.C.V. injection of vehicle. In contrast to free fatty acids, increased responses were observed in mice at 72 h after I.C.V. lysophosphatidic acid or lysophosphatidylcholine injection, and at 8 and 24 h after PAF injection, compared vehicle injected controls. Information regarding pro-nociceptive effect of specific brain lipids may be a useful basis for further studies to explore mechanism.
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Generation and maturation of bone marrow-derived DCs under serum-free conditions.
Kim, Sung Jung; Diamond, Betty
2007-06-30
Standard protocols for the generation of murine dendritic cells (DCs) employ medium supplemented with heat-inactivated fetal calf serum (FCS). Recently, several attempts have been made to avoid serum exposure during DC culture. The impetus for these efforts has been a desire to generate DCs for clinical use, as preclinical data have demonstrated their efficacy in immune activation and in immune suppression both in vitro and in vivo. However, these protocols have resulted in contradictory outcomes with respect to DC survival in culture and activation status. In this report, we compared several serum-free culture conditions with respect to survival, differentiation, activation, and cytokine profile of murine DC progenitors. DC progenitors can survive only in some serum-free conditions. Surprisingly, DCs grown in serum-free medium display a higher expression of activation markers upon stimulation. They produce increased IL-12 and decreased IL-6 following stimulation. Furthermore, DCs derived under serum-free conditions may express unusual surface markers, B220 and Ly6C/G, implying an increased differentiation to plasmacytoid DCs (pDCs).
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Scale-Free Neural and Physiological Dynamics in Naturalistic Stimuli Processing
Lin, Amy
2016-01-01
Abstract Neural activity recorded at multiple spatiotemporal scales is dominated by arrhythmic fluctuations without a characteristic temporal periodicity. Such activity often exhibits a 1/f-type power spectrum, in which power falls off with increasing frequency following a power-law function: P(f)∝1/fβ, which is indicative of scale-free dynamics. Two extensively studied forms of scale-free neural dynamics in the human brain are slow cortical potentials (SCPs)—the low-frequency (<5 Hz) component of brain field potentials—and the amplitude fluctuations of α oscillations, both of which have been shown to carry important functional roles. In addition, scale-free dynamics characterize normal human physiology such as heartbeat dynamics. However, the exact relationships among these scale-free neural and physiological dynamics remain unclear. We recorded simultaneous magnetoencephalography and electrocardiography in healthy subjects in the resting state and while performing a discrimination task on scale-free dynamical auditory stimuli that followed different scale-free statistics. We observed that long-range temporal correlation (captured by the power-law exponent β) in SCPs positively correlated with that of heartbeat dynamics across time within an individual and negatively correlated with that of α-amplitude fluctuations across individuals. In addition, across individuals, long-range temporal correlation of both SCP and α-oscillation amplitude predicted subjects’ discrimination performance in the auditory task, albeit through antagonistic relationships. These findings reveal interrelations among different scale-free neural and physiological dynamics and initial evidence for the involvement of scale-free neural dynamics in the processing of natural stimuli, which often exhibit scale-free dynamics. PMID:27822495
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Sawaraba, Ian; Rao, B K Rajashekhar
2015-01-01
Cyanide (CN) pollution was reported in the downstream areas of Watut and Markham Rivers due to effluent discharges from gold mining and processing activities of Hidden Valley mines in Morobe province of Papua New Guinea. We monitored free cyanide levels in Watut and Markham River waters randomly three times in years for 2 years (2012 and 2013). Besides, a short-term static laboratory study was conducted to evaluate the potential of river sediment to attenuate externally added cyanide, with and without the presence of biochar material. Results indicated that the free cyanide content ranged between 0.17 and 1.32 μg L(-1) in the river waters. The free cyanide content were found to be significantly (p < 0.05) greater in June (0.87 μg L(-1)) and May (0.77 μg L(-1)) months of 2012 and 2013, respectively, than the rest of the months. However, free cyanide levels in all four monitoring sites across three sampling intervals were lower than 0.20 mg L(-1) which is the maximum contaminant level (MCL) permitted according to US Environmental Protection Agency. Under laboratory conditions, the biochar-impregnated sediment showed ∼3 times more attenuation capacity for cyanide than non-amended sediment, thus indicating possibility of using biochar to cleanse cyanide from spills or other sources of pollution.
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Tareque, Md Ismail; Hoque, Nazrul; Islam, Towfiqua Mahfuza; Kawahara, Kazuo; Sugawa, Makiko
2013-12-01
Life expectancy has increased considerably throughout the world. In Bangladesh, life expectancy has increased from about 53 years in 1975 to 69 years in 2010. However, it is unknown whether the increase in life expectancy is simultaneously accompanied by an increase in disability-free life expectancy (DFLE). The purpose of the study described in this article was to explore the relationship between life expectancy and DFLE in the Rajshahi District of Bangladesh by examining the relationships between the Active Aging Index (AAI) and DFLE. The study fi ndings suggest that urban, more-educated, elderly males are more active in all aspects of life and have longer DFLE. Females are found to outlive males but are more likely to live a greater part of their remaining life with disability. Positive correlations between the AAI and DFLE suggest that older adults could enjoy more DFLE by involving themselves in active aging activities.
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Buffone, Mariano G; Zhuang, Tiangang; Ord, Teri S; Hui, Ling; Moss, Stuart B; Gerton, George L
2008-05-02
Many candidates have been proposed as zona pellucida-binding proteins. Without precluding a role for any of those candidates, we focused on mouse sperm protein ZP3R/sp56, which is localized in the acrosomal matrix. The objective of this study was to analyze the role of ZP3R/sp56 in mouse fertilization. We expressed recombinant ZP3R/sp56 as a secreted protein in HEK293 cells and purified it from serum-free, conditioned medium. In the presence of reducing agents, the recombinant ZP3R/sp56 exhibited a molecular weight similar to that observed for the native ZP3R/sp56. Reminiscent of the native protein, recombinant ZP3R/sp56 formed a high molecular weight, disulfide cross-linked oligomer consisting of six or more monomers under non-reducing conditions. Recombinant ZP3R/sp56 bound to the zona pellucida of unfertilized eggs but not to 2-cell embryos, indicating that the changes that take place in the zona pellucida at fertilization affected the interaction of this protein with the zona pellucida. The extent of in vitro fertilization was reduced in a dose-dependent manner when unfertilized eggs were preincubated with recombinant ZP3R/sp56 (74% drop at the maximum concentrations assayed). Eggs incubated with the recombinant protein showed an absence of or very few sperm in the perivitelline space, suggesting that the reduction in the fertilization rate is caused by the inhibition of sperm binding and/or penetration through the zona pellucida. These results indicate that sperm ZP3R/sp56 is important for sperm-zona interactions during fertilization and support the concept that the acrosomal matrix plays an essential role in mediating the binding of sperm to the zona pellucida.
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A comparison of free weight squat to Smith machine squat using electromyography.
Schwanbeck, Shane; Chilibeck, Philip D; Binsted, Gordon
2009-12-01
The purpose of this experiment was to determine whether free weight or Smith machine squats were optimal for activating the prime movers of the legs and the stabilizers of the legs and the trunk. Six healthy participants performed 1 set of 8 repetitions (using a weight they could lift 8 times, i.e., 8RM, or 8 repetition maximum) for each of the free weight squat and Smith machine squat in a randomized order with a minimum of 3 days between sessions, while electromyographic (EMG) activity of the tibialis anterior, gastrocnemius, vastus medialis, vastus lateralis, biceps femoris, lumbar erector spinae, and rectus abdominus were simultaneously measured. Electromyographic activity was significantly higher by 34, 26, and 49 in the gastrocnemius, biceps femoris, and vastus medialis, respectively, during the free weight squat compared to the Smith machine squat (p < 0.05). There were no significant differences between free weight and Smith machine squat for any of the other muscles; however, the EMG averaged over all muscles during the free weight squat was 43% higher when compared to the Smith machine squat (p < 0.05). The free weight squat may be more beneficial than the Smith machine squat for individuals who are looking to strengthen plantar flexors, knee flexors, and knee extensors.
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Brefeldin A Inhibits Cell-Free, De Novo Synthesis of Poliovirus
Cuconati, Andrea; Molla, Akhteruzzaman; Wimmer, Eckard
1998-01-01
Brefeldin A (BFA), an inhibitor of intracellular vesicle-dependent secretory transport, is a potent inhibitor of poliovirus RNA replication in infected cells. We have determined that the unknown mechanism of BFA inhibition of replication is reproduced in the cell-free poliovirus translation, replication, and encapsidation system. Furthermore, we provide evidence suggesting that the cellular mechanism targeted by BFA, the GTP-dependent synthesis of secretory transport vesicles, may be involved in viral RNA replication in the system via a soluble cellular GTP-binding and -hydrolyzing activity. This activity is related to the ARF (ADP-ribosylation factor) family of GTP-binding proteins. ARFs are required for the formation of several classes of secretory vesicles, and some family members are indirectly inactivated by BFA. Peptides that function as competitive inhibitors of ARF activity in cell-free transport systems also inhibit poliovirus RNA replication, and this inhibitory effect can be countered by the addition of exogenous ARF. We suggest that BFA inhibition of replication is diagnostic of a requirement for ARF activity in the cell-free system. PMID:9658088
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Khalilian, Morteza; Navidbakhsh, Mahdi; Valojerdi, Mojtaba Rezazadeh; Chizari, Mahmoud; Yazdi, Poopak Eftekhari
2010-01-01
The zona pellucida (ZP) is the spherical layer that surrounds the mammalian oocyte. The physical hardness of this layer plays a crucial role in fertilization and is largely unknown because of the lack of appropriate measuring and modelling methods. The aim of this study is to measure the biomechanical properties of the ZP of human/mouse ovum and to test the hypothesis that Young's modulus of the ZP varies with fertilization. Young's moduli of ZP are determined before and after fertilization by using the micropipette aspiration technique, coupled with theoretical models of the oocyte as an elastic incompressible half-space (half-space model), an elastic compressible bilayer (layered model) or an elastic compressible shell (shell model). Comparison of the models shows that incorporation of the layered geometry of the ovum and the compressibility of the ZP in the layered and shell models may provide a means of more accurately characterizing ZP elasticity. Evaluation of results shows that although the results of the models are different, all confirm that the hardening of ZP will increase following fertilization. As can be seen, different choices of models and experimental parameters can affect the interpretation of experimental data and lead to differing mechanical properties. PMID:19828504
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Serendipitous Findings While Researching Oxygen Free Radicals
Floyd, Robert A.
2009-01-01
This review is based on the honor of receiving the Discovery Award from the Society of Free Radical Biology and Medicine. The review is reflective and presents our thinking which led to experiments that yielded novel observations. Critical questioning of our understanding of oxygen free radicals in biomedical problems led us to use and develop more direct and extremely sensitive methods. This included nitrone free radical spin-trapping and HPLC-electrochemical detection. This technology led to the pioneering use of salicylate to trap hydroxyl free radicals and show increased flux in ischemia/reperfused brain regions and to also first sensitively detect 8-hydroxy-droxyguanosine (8-OHdG) in oxidative-damaged DNA and help assess its role in cancer development. We demonstrated that Methylene Blue (MB) photo-induced formation of 8-hydroxy-guanine in DNA and RNA and discovered that MB sensitively photo-inactivated RNA viruses including HIV and the West Nile Virus. Studies in experimental stroke led us to serendipitously discover that α-phenyl-tert-butylnitrone (PBN) was neuroprotective if given after the stroke. This led to extensive commercial development of NXY-059, a PBN derivative, for the treatment of stroke. More recently we discovered that PBN-nitrones have potent anti-cancer activity and are active in preventing hearing loss caused by acute acoustical trauma. PMID:19439210
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2014-01-01
Background To validate physical activity estimates by the Sensewear Pro3 activity monitor compared with indirect calorimetry during simulated free living in patients diagnosed with osteoarthritis of the hip pre or post total hip arthroplasty. Methods Twenty patients diagnosed with hip osteoarthritis (10 pre- and 10 post total hip arthroplasty; 40% female; age: 63.3 ± 9.0; BMI: 23.7 ± 3.7). All patients completed a 2 hour protocol of simulated free living with 8 different typical physical activity types. Energy consumption (kcal/min) was estimated by the Sense Wear pro3 Armband activity monitor and validated against indirect calorimetry (criterion method) by means of a portable unit (Cosmed K4b2). Bias and variance was analyzed using functional ANOVA. Results Mean bias during all activities was 1.5 Kcal/min 95%CI [1.3; 1.8] corresponding to 72% (overestimation). Normal gait speed showed an overestimation of 2.8 Kcal/min, 95%CI [2.3; 3.3] (93%) while an underestimation of -1.1 Kcal/min, 95%CI [-1.8; -0.3] (-25%) was recorded during stair climb. Activities dominated by upper body movements showed large overestimation with 4.37 Kcal/min, 95%CI [3.8; 5.1] (170%) being recorded during gardening. Both bias and variance appeared to be dependent on activity type. Conclusion The activity monitor generally overestimated the energy consumption during common activities of low to medium intensity in the patient group. The size and direction of the bias was highly dependent on the activity type which indicates the activity monitor is of limited value in patients with hip osteoarthritis and that the results do not express the real energy expenditure. PMID:24552503
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Association of eye color and sex with basketball free throws by elementary school children.
Patee, T; Frewen, M; Beer, J
1991-12-01
Dark-eyed individuals perform reactive activities better while light-eyed individuals generally perform self-paced activities better. There were 68 (21 dark- and 47 light-eyed) elementary school children who shot 5 practice and then 15 free throws from the free-throw line in a high school gym. There were no differences in performance between light- and dark-eyed children, but boys scored more free throws than girls.
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NASA Technical Reports Server (NTRS)
Smith, D. L.; Krikorian, A. D.
1990-01-01
Wounded zygotic embryos of cultivated carrot produce somatic proembryos on hormone-free nutrient medium containing 1 mM NH4+ as the sole nitrogen source. Continued maintenance of proembryos on this medium leads to a "pure" culture of preglobular stage proembryos (PGSPs). Ethylene had no effect on this process. Also, somatic embryo production was not affected by growing cultures on activated charcoal-impregnated filter papers. However, somatic proembyros initiated on activated charcoal papers were not maintainable as PGSPs and developed into later embryo stages. Normally, medium pH dropped from 5.7 to 4 during each subculture period, but when using activated charcoal papers the pH endpoint was around 6 - 7 due to a leachable substance(s) within the filter papers. When powdered, activated charcoal was used in the medium as an adsorbent of products potentially released after wounding, pH dropped at the normal rate and to the expected levels; proembryos did not mature into later embryo stages and were maintainable exclusively as PGSPs. Low pH (approximately 4) is detrimental to proembyro production, but is essential to maintaining PGSPs on hormone-free nutrient medium, whereas a sustained pH > or = 5.7 allows continued development of PGSPs into later embryo stages.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Wynn, R. Max; Kato, Masato; Chuang, Jacinta L.
2008-10-21
Human pyruvate dehydrogenase complex (PDC) is down-regulated by pyruvate dehydrogenase kinase (PDK) isoforms 1-4. PDK4 is overexpressed in skeletal muscle in type 2 diabetes, resulting in impaired glucose utilization. Here we show that human PDK4 has robust core-free basal activity, which is considerably higher than activity levels of other PDK isoforms stimulated by the PDC core. PDK4 binds the L3 lipoyl domain, but its activity is not significantly stimulated by any individual lipoyl domains or the core of PDC. The 2.0-{angstrom} crystal structures of the PDK4 dimer with bound ADP reveal an open conformation with a wider active-site cleft, comparedmore » with that in the closed conformation epitomized by the PDK2-ADP structure. The open conformation in PDK4 shows partially ordered C-terminal cross-tails, in which the conserved DW (Asp{sup 394}-Trp{sup 395}) motif from one subunit anchors to the N-terminal domain of the other subunit. The open conformation fosters a reduced binding affinity for ADP, facilitating the efficient removal of product inhibition by this nucleotide. Alteration or deletion of the DW-motif disrupts the C-terminal cross-tail anchor, resulting in the closed conformation and the nearly complete inactivation of PDK4. Fluorescence quenching and enzyme activity data suggest that compounds AZD7545 and dichloroacetate lock PDK4 in the open and the closed conformational states, respectively. We propose that PDK4 with bound ADP exists in equilibrium between the open and the closed conformations. The favored metastable open conformation is responsible for the robust basal activity of PDK4 in the absence of the PDC core.« less
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Wynn, R Max; Kato, Masato; Chuang, Jacinta L; Tso, Shih-Chia; Li, Jun; Chuang, David T
2008-09-12
Human pyruvate dehydrogenase complex (PDC) is down-regulated by pyruvate dehydrogenase kinase (PDK) isoforms 1-4. PDK4 is overexpressed in skeletal muscle in type 2 diabetes, resulting in impaired glucose utilization. Here we show that human PDK4 has robust core-free basal activity, which is considerably higher than activity levels of other PDK isoforms stimulated by the PDC core. PDK4 binds the L3 lipoyl domain, but its activity is not significantly stimulated by any individual lipoyl domains or the core of PDC. The 2.0-A crystal structures of the PDK4 dimer with bound ADP reveal an open conformation with a wider active-site cleft, compared with that in the closed conformation epitomized by the PDK2-ADP structure. The open conformation in PDK4 shows partially ordered C-terminal cross-tails, in which the conserved DW (Asp(394)-Trp(395)) motif from one subunit anchors to the N-terminal domain of the other subunit. The open conformation fosters a reduced binding affinity for ADP, facilitating the efficient removal of product inhibition by this nucleotide. Alteration or deletion of the DW-motif disrupts the C-terminal cross-tail anchor, resulting in the closed conformation and the nearly complete inactivation of PDK4. Fluorescence quenching and enzyme activity data suggest that compounds AZD7545 and dichloroacetate lock PDK4 in the open and the closed conformational states, respectively. We propose that PDK4 with bound ADP exists in equilibrium between the open and the closed conformations. The favored metastable open conformation is responsible for the robust basal activity of PDK4 in the absence of the PDC core.
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The Markov blankets of life: autonomy, active inference and the free energy principle
Palacios, Ensor; Friston, Karl; Kiverstein, Julian
2018-01-01
This work addresses the autonomous organization of biological systems. It does so by considering the boundaries of biological systems, from individual cells to Home sapiens, in terms of the presence of Markov blankets under the active inference scheme—a corollary of the free energy principle. A Markov blanket defines the boundaries of a system in a statistical sense. Here we consider how a collective of Markov blankets can self-assemble into a global system that itself has a Markov blanket; thereby providing an illustration of how autonomous systems can be understood as having layers of nested and self-sustaining boundaries. This allows us to show that: (i) any living system is a Markov blanketed system and (ii) the boundaries of such systems need not be co-extensive with the biophysical boundaries of a living organism. In other words, autonomous systems are hierarchically composed of Markov blankets of Markov blankets—all the way down to individual cells, all the way up to you and me, and all the way out to include elements of the local environment. PMID:29343629
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Beagle, Brandon; Mi, Kaihong; Johnson, Gail V W
2009-11-01
The canonical Wnt/beta-catenin signaling pathway plays a critical role in numerous physiological and pathological processes. LRP6 is an essential co-receptor for Wnt/beta-catenin signaling; as transduction of the Wnt signal is strongly dependent upon GSK3beta-mediated phosphorylation of multiple PPP(S/T)P motifs within the membrane-anchored LRP6 intracellular domain. Previously, we showed that the free LRP6 intracellular domain (LRP6-ICD) can activate the Wnt/beta-catenin pathway in a beta-catenin and TCF/LEF-1 dependent manner, as well as interact with and attenuate GSK3beta activity. However, it is unknown if the ability of LRP6-ICD to attenuate GSK3beta activity and modulate activation of the Wnt/beta-catenin pathway requires phosphorylation of the LRP6-ICD PPP(S/T)P motifs, in a manner similar to the membrane-anchored LRP6 intracellular domain. Here we provide evidence that the LRP6-ICD does not have to be phosphorylated at its PPP(S/T)P motif by GSK3beta to stabilize endogenous cytosolic beta-catenin resulting in activation of TCF/LEF-1 and the Wnt/beta-catenin pathway. LRP6-ICD and a mutant in which all 5 PPP(S/T)P motifs were changed to PPP(A)P motifs equivalently interacted with and attenuated GSK3beta activity in vitro, and both constructs inhibited the in situ GSK3beta-mediated phosphorylation of beta-catenin and tau to the same extent. These data indicate that the LRP6-ICD attenuates GSK3beta activity similar to other GSK3beta binding proteins, and is not a result of it being a GSK3beta substrate. Our findings suggest the functional and regulatory mechanisms governing the free LRP6-ICD may be distinct from membrane-anchored LRP6, and that release of the LRP6-ICD may provide a complimentary signaling cascade capable of modulating Wnt-dependent gene expression. (c) 2009 Wiley-Liss, Inc.
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Cheng, Rui; Tao, Mangjuan; Shi, Zhilu; Zhang, Xiafei; Jin, Yan; Li, Baoxin
2015-11-15
Several fluorescence signal amplification strategies have been developed for sensitive detection of T4 polynucleotide kinase (T4 PNK) activity, but they need fluorescence dye labeled DNA probe. We have addressed the limitation and report here a label-free strategy for sensitive detection of PNK activity by coupling DNA strand displacement reaction with enzymatic-aided amplification. A hairpin oligonucleotide (hpDNA) with blunt ends was used as the substrate for T4 PNK phosphorylation. In the presence of T4 PNK, the stem of hpDNA was phosphorylated and further degraded by lambda exonuclease (λ exo) from 5' to 3' direction to release a single-stranded DNA as a trigger of DNA strand displacement reaction (SDR). The trigger DNA can continuously displace DNA P2 from P1/P2 hybrid with the help of specific cleavage of nicking endonuclease (Nt.BbvCI). Then, DNA P2 can form G-quadruplex in the presence of potassium ions and quadruplex-selective fluorphore, N-methyl mesoporphyrin IX (NMM), resulting in a significant increase in fluorescence intensity of NMM. Thus, the accumulative release of DNA P2 led to fluorescence signal amplification for determining T4 PNK activity with a detection limit of 6.6×10(-4) U/mL, which is superior or comparative with established approaches. By ingeniously utilizing T4 PNK-triggered DNA SDR, T4 PNK activity can be specifically and facilely studied in homogeneous solution containing complex matrix without any external fluorescence labeling. Moreover, the influence of different inhibitors on the T4 PNK activity revealed that it also can be explored to screen T4 PNK inhibitors. Therefore, this label-free amplification strategy presents a facile and cost-effective approach for nucleic acid phosphorylation related research. Copyright © 2015 Elsevier B.V. All rights reserved.
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NASA Elementary Aerospace Activities Free to Members
ERIC Educational Resources Information Center
Journal of Aerospace Education, 1978
1978-01-01
Describes the contents of Elementary School Aerospace Activities: A Resource for Teachers. Activities examine a variety of topics in aerospace education and are intended to be used with children ages 5-11. The book is available from the Government Printing Office (GPO) for $3.00. (CP)