Effect of Monazite Coating on Tensile Properties of Nextel 720 Fibers, Tows and Minicomposites

ABSTRACTThe tensile strengths of Nextel™ 720 fibers as well as tows and minicomposites made of these fibers were measured to study the effects of monazite coating at room temperature (RT) and 1200°C (HT). Tests were conducted on as-received materials (called unsoaked) as well as materials that had been thermally soaked at HT for 100 hours. Weibull analysis of fiber strength data shows close agreement between the Weibull modulus obtained from the statistical fracture distribution and the modulus obtained from a study of the gage length dependence of strength. The monazite coating does not change the RT strength of unsoaked single fibers, but has a beneficial effect in terms of strength retention under HT testing. This beneficial effect of the coating disappears for soaked samples. The results for tows and minicomposites also indicate that for the unsoaked condition, tensile failure appears to be driven by fiber surface flaws and the presence of the monazite coatings clearly improves both RT and HT strength of fibers, tows and minicomposites. However, the beneficial effects of the coating disappear after long term exposure to HT.

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Comparative Labelling and Biokinetic Studies of 99mTc-EDTA(Sn) and 99mTc-DTPA(Sn)

Nuklearmedizin ◽

10.1055/s-0037-1620603 ◽

1977 ◽

Vol 16 (01) ◽

pp. 30-35 ◽

Cited By ~ 1

Author(s):

N. Agha ◽

R. B. R. Persson

Keyword(s):

Complex Formation ◽

Significant Influence ◽

Room Temperature ◽

Ph Value ◽

Maximum Activity ◽

Reduction Step ◽

Labelling Yield ◽

Different Temperatures ◽

Kinetics Of

SummaryGelchromatography column scanning has been used to study the fractions of 99mTc-pertechnetate, 99mTcchelate and reduced hydrolyzed 99mTc in preparations of 99mTc-EDTA(Sn) and 99mTc-DTPA(Sn). The labelling yield of 99mTc-EDTA(Sn) chelate was as high as 90—95% when 100 μmol EDTA · H4 and 0.5 (Amol SnCl2 was incubated with 10 ml 99mTceluate for 30—60 min at room temperature. The study of the influence of the pH-value on the fraction of 99mTc-EDTA shows that pH 2.8—2.9 gave the best labelling yield. In a comparative study of the labelling kinetics of 99mTc-EDTA(Sn) and 99mTc- DTPA(Sn) at different temperatures (7, 22 and 37°C), no significant influence on the reduction step was found. The rate constant for complex formation, however, increased more rapidly with increased temperature for 99mTc-DTPA(Sn). At room temperature only a few minutes was required to achieve a high labelling yield with 99mTc-DTPA(Sn) whereas about 60 min was required for 99mTc-EDTA(Sn). Comparative biokinetic studies in rabbits showed that the maximum activity in kidneys is achieved after 12 min with 99mTc-EDTA(Sn) but already after 6 min with 99mTc-DTPA(Sn). The long-term disappearance of 99mTc-DTPA(Sn) from the kidneys is about five times faster than that for 99mTc-EDTA(Sn).

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Shedding New Light on Mountainous Forest Growth: A Cross-Scale Evaluation of the Effects of Topographic Illumination Correction on 25 Years of Forest Cover Change across Nepal

Remote Sensing ◽

10.3390/rs13112131 ◽

2021 ◽

Vol 13 (11) ◽

pp. 2131

Author(s):

Jamon Van Den Hoek ◽

Alexander C. Smith ◽

Kaspar Hurni ◽

Sumeet Saksena ◽

Jefferson Fox

Keyword(s):

Remote Sensing ◽

Geographic Distribution ◽

Classification Accuracy ◽

Forest Cover ◽

Forest Growth ◽

Forest Cover Change ◽

Scale Evaluation ◽

Beneficial Effects ◽

Affect Detection

Accurate remote sensing of mountainous forest cover change is important for myriad social and ecological reasons, but is challenged by topographic and illumination conditions that can affect detection of forests. Several topographic illumination correction (TIC) approaches have been developed to mitigate these effects, but existing research has focused mostly on whether TIC improves forest cover classification accuracy and has usually found only marginal gains. However, the beneficial effects of TIC may go well beyond accuracy since TIC promises to improve detection of low illuminated forest cover and thereby normalize measurements of the amount, geographic distribution, and rate of forest cover change regardless of illumination. To assess the effects of TIC on the extent and geographic distribution of forest cover change, in addition to classification accuracy, we mapped forest cover across mountainous Nepal using a 25-year (1992–2016) gap-filled Landsat time series in two ways—with and without TIC (i.e., nonTIC)—and classified annual forest cover using a Random Forest classifier. We found that TIC modestly increased classifier accuracy and produced more conservative estimates of net forest cover change across Nepal (−5.2% from 1992–2016) TIC. TIC also resulted in a more even distribution of forest cover gain across Nepal with 3–5% more net gain and 4–6% more regenerated forest in the least illuminated regions. These results show that TIC helped to normalize forest cover change across varying illumination conditions with particular benefits for detecting mountainous forest cover gain. We encourage the use of TIC for satellite remote sensing detection of long-term mountainous forest cover change.

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Long-Term Caloric Restriction Attenuates β-Amyloid Neuropathology and Is Accompanied by Autophagy in APPswe/PS1delta9 Mice

Nutrients ◽

10.3390/nu13030985 ◽

2021 ◽

Vol 13 (3) ◽

pp. 985

Author(s):

Luisa Müller ◽

Nicole Power Guerra ◽

Jan Stenzel ◽

Claire Rühlmann ◽

Tobias Lindner ◽

...

Keyword(s):

Caloric Restriction ◽

Neuroprotective Effect ◽

Resonance Spectroscopy ◽

Neuroprotective Effects ◽

Beneficial Effects ◽

Positron Emission ◽

Pet Ct ◽

Amyloid Aβ ◽

Β Amyloid

Caloric restriction (CR) slows the aging process, extends lifespan, and exerts neuroprotective effects. It is widely accepted that CR attenuates β-amyloid (Aβ) neuropathology in models of Alzheimer’s disease (AD) by so-far unknown mechanisms. One promising process induced by CR is autophagy, which is known to degrade aggregated proteins such as amyloids. In addition, autophagy positively regulates glucose uptake and may improve cerebral hypometabolism—a hallmark of AD—and, consequently, neural activity. To evaluate this hypothesis, APPswe/PS1delta9 (tg) mice and their littermates (wild-type, wt) underwent CR for either 16 or 68 weeks. Whereas short-term CR for 16 weeks revealed no noteworthy changes of AD phenotype in tg mice, long-term CR for 68 weeks showed beneficial effects. Thus, cerebral glucose metabolism and neuronal integrity were markedly increased upon 68 weeks CR in tg mice, indicated by an elevated hippocampal fluorodeoxyglucose [18F] ([18F]FDG) uptake and increased N-acetylaspartate-to-creatine ratio using positron emission tomography/computer tomography (PET/CT) imaging and magnet resonance spectroscopy (MRS). Improved neuronal activity and integrity resulted in a better cognitive performance within the Morris Water Maze. Moreover, CR for 68 weeks caused a significant increase of LC3BII and p62 protein expression, showing enhanced autophagy. Additionally, a significant decrease of Aβ plaques in tg mice in the hippocampus was observed, accompanied by reduced microgliosis as indicated by significantly decreased numbers of iba1-positive cells. In summary, long-term CR revealed an overall neuroprotective effect in tg mice. Further, this study shows, for the first time, that CR-induced autophagy in tg mice accompanies the observed attenuation of Aβ pathology.

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Yields and nitrogen uptake of grain sorghum in various rotations, including lucerne, annual legume and long fallow

Australian Journal of Agricultural Research ◽

10.1071/ar9890255 ◽

1989 ◽

Vol 40 (2) ◽

pp. 255 ◽

Cited By ~ 1

Author(s):

ICR Holford

Keyword(s):

Nitrogen Uptake ◽

Grain Sorghum ◽

Grazing Management ◽

First Year ◽

Red Clay ◽

Beneficial Effects ◽

South Wales ◽

Establishment Method ◽

Soil Evidence

Long-term yields, nitrogen uptake and responsiveness of grain sorghum following three lucerne rotations, an annual legume rotation, long fallowing, and continuous wheat growing were measured on a black earth and red clay in northern New South Wales. The three lucerne rotations compared two methods of lucerne establishment (with or without a cover crop) and two methods of grazing management (short or extended grazing).There were large beneficial effects of lucerne leys on the first grain sorghum crop, whether they were measured as grain yield, nitrogen content of the foliage and grain, or nitrogen uptake. The effect was much smaller in the second year but it increased in the third and fourth years, in direct relation to the rainfall during the sorghum flowering period. The effect was larger on the black earth than on the red clay, reflecting the much higher lucerne yields on the former soil. Evidence indicated that the nitrogen contribution from lucerne after the first year was no greater than the nitrogen accumulated by long fallowing, and this was attributed to very low rainfall and lucerne yields during the four year ley period.The annual legume rotation suffered from drought and insect damage in most years, and following sorghum yields tended to be lower than those achieved by long fallowing.Differences in the effects of establishment method and grazing management on total lucerne yields were reflected in the differences in subsequent grain sorghum yields. Largest differences were on the black earth where extended grazing lowered the total yields of lucerne and subsequent grain sorghum. Sowing lucerne under wheat had little effect on total yields of lucerne or sorghum.

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Water repellent room temperature vulcanized silicone for enhancing the long-term stability of perovskite solar cells

Solar Energy ◽

10.1016/j.solener.2021.02.035 ◽

2021 ◽

Vol 218 ◽

pp. 28-34

Author(s):

Mahmoud Samadpour ◽

Mahsa Heydari ◽

Mahdi Mohammadi ◽

Parisa Parand ◽

Nima Taghavinia

Keyword(s):

Solar Cells ◽

Room Temperature ◽

Perovskite Solar Cells ◽

Water Repellent ◽

Term Stability ◽

Long Term Stability

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The beneficial effects of Lactobacillus fermented black barley on high fat diet-induced fatty liver in rats

Food & Function ◽

10.1039/d1fo00290b ◽

2021 ◽

Author(s):

Qi Guan ◽

Xinwen Ding ◽

Lingyue Zhong ◽

Chuang Zhu ◽

Pan Nie ◽

...

Keyword(s):

Fatty Liver ◽

High Fat Diet ◽

Metabolic Disorders ◽

High Fat ◽

Beneficial Effects ◽

Phytochemical Composition

Long term high-fat diet (HF) can cause metabolic disorders, which might induce fatty liver. Fermented whole cereal food exhibit healthy potential due to their unique phytochemical composition and probiotics. In...

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Hallucinogenic/psychedelic 5HT2A receptor agonists as rapid antidepressant therapeutics: Evidence and mechanisms of action

Journal of Psychopharmacology ◽

10.1177/0269881120986422 ◽

2021 ◽

pp. 026988112098642

Author(s):

Rafael Guimarães dos Santos ◽

Jaime EC Hallak ◽

Glen Baker ◽

Serdar Dursun

Keyword(s):

Health Care Systems ◽

Treatment Compliance ◽

Therapeutic Effects ◽

Beneficial Effects ◽

Antidepressant Effects ◽

Care Systems ◽

Drug Treatments ◽

Fast Acting

Major depressive disorder (MDD) is among the most prevalent mental health disorders worldwide, and it is associated with a reduced quality of life and enormous costs to health care systems. Available drug treatments show low-to-moderate response in most patients, with almost a third of patients being non-responders (treatment-resistant). Furthermore, most currently available medications need several weeks to achieve therapeutic effects, and the long-term use of these drugs is often associated with significant unwanted side effects and resultant reductions in treatment compliance. Therefore, more effective, safer, and faster-acting antidepressants with enduring effects are needed. Together with ketamine, psychedelics (or classic or serotoninergic hallucinogens) such as lysergic acid diethylamide (LSD), psilocybin, and ayahuasca are among the few compounds with recent human evidence of fast-acting antidepressant effects. Several studies in the 1950s to 1970s reported antidepressive and anxiolytic effects of these drugs, which are being confirmed by modern trials (LSD, one trial; psilocybin, five trials; ayahuasca, two trials). The effects of these drugs appear to be produced primarily by their agonism at serotonin (5-hydroxytryptamine, 5-HT) receptors, especially the 5-HT2A receptor. Considering the overall burden of MDD and the necessity of new therapeutic options, the promising (but currently limited) evidence of safety and efficacy of psychedelics has encouraged the scientific community to explore more fully their beneficial effects in MDD.

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Verbal threat learning does not spare loved ones

Scientific Reports ◽

10.1038/s41598-021-84921-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Cristina Morato ◽

Pedro Guerra ◽

Florian Bublatzky

Keyword(s):

Fear Learning ◽

Pain Experience ◽

Trauma Research ◽

Learning History ◽

Beneficial Effects ◽

Electric Shocks ◽

History Of ◽

Threat Cues ◽

Verbal Threat

AbstractSignificant others provide individuals with a sense of safety and security. However, the mechanisms that underlie attachment-induced safety are hardly understood. Recent research has shown beneficial effects when viewing pictures of the romantic partner, leading to reduced pain experience and defensive responding. Building upon this, we examined the inhibitory capacity of loved face pictures on fear learning in an instructed threat paradigm. Pictures of loved familiar or unknown individuals served as signals for either threat of electric shocks or safety, while a broad set of psychophysiological measures was recorded. We assumed that a long-term learning history of beneficial relations interferes with social threat learning. Nevertheless, results yielded a typical pattern of physiological defense activation towards threat cues, regardless of whether threat was signaled by an unknown or a loved face. These findings call into question the notion that pictures of loved individuals are shielded against becoming threat cues, with implications for attachment and trauma research.

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