Bibliografie tematiche / Active oxygen

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Letteratura scientifica selezionata sul tema "Active oxygen"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 31 luglio 2024

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Articoli di riviste sul tema "Active oxygen"

Yoshikawa, Toshikazu, Toru Tanigawa e Motoharu Kondo. "Active oxygen species." Ensho 8, n. 6 (1988): 511–16. http://dx.doi.org/10.2492/jsir1981.8.511.

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SANAKA, TSUTOMU. "Active oxygen hypothesis." Journal of Japanese Society for Dialysis Therapy 24, n. 3 (1991): 283–87. http://dx.doi.org/10.4009/jsdt1985.24.283.

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OHNO, Hideki, Shuji OH-ISHI e Takako KIZAKI. "Exercise and Active Oxygen." Kagaku To Seibutsu 33, n. 8 (1995): 520–27. http://dx.doi.org/10.1271/kagakutoseibutsu1962.33.520.

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Pryor, W. A. "Active oxygen in biochemistry". Free Radical Biology and Medicine 21, n. 7 (gennaio 1996): 1011. http://dx.doi.org/10.1016/s0891-5849(96)00287-0.

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KANEGASAKI, Shiro. "Leukocytes and active oxygen." Nippon Saikingaku Zasshi 47, n. 5 (1992): 671–78. http://dx.doi.org/10.3412/jsb.47.671.

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MIYAZAWA, TERUO. "Generation, elimination and effects of active oxygen.1.Active oxygen and lipid." Kagaku To Seibutsu 29, n. 12 (1991): 798–806. http://dx.doi.org/10.1271/kagakutoseibutsu1962.29.798.

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KAWAGISHI, TOSHIAKI. "Generation, erasure and effects of active oxygen.(3).Active oxygen and protein." Kagaku To Seibutsu 30, n. 2 (1992): 122–29. http://dx.doi.org/10.1271/kagakutoseibutsu1962.30.122.

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INOUE, MASAYASU. "Generation, disappearance, and effect of active oxygen.4.Active oxygen and diseases." Kagaku To Seibutsu 30, n. 3 (1992): 184–90. http://dx.doi.org/10.1271/kagakutoseibutsu1962.30.184.

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KASHIMURA, NAOKI. "Generation, elimination and effects of active oxygen.2.Active oxygen and carbohydrate." Kagaku To Seibutsu 30, n. 1 (1992): 40–49. http://dx.doi.org/10.1271/kagakutoseibutsu1962.30.40.

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KUNINORI, Toyo. "Damage of protein by active oxygen. Interaction of food proteins with active oxygen." Journal of the agricultural chemical society of Japan 62, n. 7 (1988): 1120–23. http://dx.doi.org/10.1271/nogeikagaku1924.62.1120.

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Tesi sul tema "Active oxygen"

Gutowski, Mariusz. "Molecular detection and characterisation of biologically relevant free radicals during surgical ischaemia-reperfusion". Thesis, University of South Wales, 2011. https://pure.southwales.ac.uk/en/studentthesis/molecular-detection-and-charcaterisation-of-biologically-relevant-free-radicals-during-surgical-ischaemiareperfusion(016f6447-5d02-45f7-a543-8b880148dc23).html.

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Abstract (sommario):

Oxygen is one of the most important molecules in human beings. Our research is focused on how the human body can respond and adapt to the physiological challenge posed by a lack of oxygen. Ascorbic acid (Vitamin C) is one of the most important and considered the most effective water-soluble, chain-breaking antioxidant in human plasma, with the capacity to prevents damage by free radicals. This thesis presents four studies investigating the phenomenon of Reactive Oxygen Species (ROS) generation in the many different surgical conditions in the animal and in the human. Study one investigated the geometry and thermodynamic properties of vitamin C. Calculations were carried out at the restricted and unrestricted B3LYP/6-31+G(d,p), B3LYP/6-311++G(d,p) and B3LYP/EPR-II levels for two conformers (1 and 2) of L-ascorbic acid and their respective oxidation products to monodehydroascorbates of ab-initio methods by Gaussian O3W package. Conformer 1, free radical properties are compared with previously published calculations in the gaseous and aqueous solution states and with experimental EPR values. Calculated molecular structures, EPR (electron paramagnetic resonance spectroscopy), the vibration spectral and energetic properties and all are reported including some proposed changes to previous EPR assignments. Conformer 2 of L-ascorbic acid is predicted to have lower energy than Conformer 1, under the method and basis sets used, by between 11 and 26 kJ mol-1 and is stabilised by internal hydrogen bonding. Relaxed potential energy surface (PES) scans were carried out for two proton transfer processes and relative energies of stable minima and barriers between them determined. Hydrogen transfer is predicted in two systems with favourable spatial arrangements of O–H and O groups for which relaxed potential energy surface scans are reported. Calculated vibrational wavenumber values are provided for selected C=C, C=O, C–H and O–H modes assigned to particular groups and significant calculated EPR hyperfine coupling constants (HCC) values for splitting by H(1) and C(13) for radical species are also reported. These calculations contribute to a better understanding of the complex role of L-ascorbic acid and its various oxidised, neutral, ionic and radical forms in biochemistry and medicine. Study two examined if vitamin C could ameliorate the damaging effects of I-R on myocardium and we postulated that the mechanism of vitamin C protection against iii I-R-induced cell death involved quenching of ROS. In the vitamin C group after 5 min of reperfusion a significant, sudden increase of diastolic pressure in the heart was noted and reached a maximum of 77 mmHg after 12 min of reperfusion and then gradually decreased to 51 mmHg after 60 min of reperfusion period but was quicker than in Control group reaching 37 mmHg by the end of the reperfusion period. The level of A·− (ascorbate free radicals) sudden and massive increased at the time of reperfusion in the Vitamin C group. This increase was associated with poor mechanical function in hearts as indicated by the significantly depressed recovery process. After 30 min of global, now-flow ischaemia and 60min of reperfusion infarct size averaged 33% ± 1 in Control group and 30 % ± 1 in Vitamin C group, respectively, (P<0.05). There is strong evidence that oxygen centered radicals contribute to postischaemic dysfunction after global ischaemia. Our data unquestionably suggest that the large production of A·− was associated with a greater depression in myocardial contractile function, therefore could represent a marker of oxidative stress during I-R and could be related to the functional impairment during reperfusion. In summary, we have used the animal models of isolated heart perfusion to provide evidence that vitamin C did not reduce the infarct size, however “tendency” towards a decrease (↓) in infarct size with ascorbate and it protects from oxidative damage during global I-R as manifested by decreased concentrations of A·− and enhance recovery of mechanical function such as diastolic pressure and LVDP in postischaemic working rat hearts. Study three was designed to test the hypothesis that the physiological trauma associated with venous cannulation may artefactually stimulate systemic free radical formation in the acute phase that if not accounted for may under-estimate the oxidative stress response to exercise. The relationship between the time of venepuncture and the level of free radical generation during normoxic conditions was further investigated. The venous cannulation in Phase I, increased plasma A·− by 347 ± 173 AU/√G, P <0.05 after 2min of venepuncture with further increases observed after 5min and 10min of venous cannulation, respectively (403 ± 178 AU/√G; 462 ± 93 AU/√G, P < 0.05) vs baseline point time. After this time the level of A·− slightly blunted as to achieve a similar level to baseline point control after 30 minutes. In phase II the exerciseinduced increase in A·− was subsequently shown to be 48% greater (30min as opposed to the 2min post-cannulation resting baseline)(1754 ± 361 vs. 1979 ± 375 AU, P <0.05). Our findings demonstrate and confirm that venous cannulation per se stimulates iv the systemic formation of free radicals as an acute phase response which peaks at 10min and require approximately 15min to normalise. This has important interpretive implications for future studies that employ catheterisation. The final Study examined if the combination of exercise and inspiratory hypoxia would further compound regional tissue de-oxygenation that is frequently encountered during the ischaemic phase of surgery and thus, by consequence increase oxidative stress. The aim of the study was to further understand a potential relationship between oxidative stress and alterations in muscle oxygenation. Clear significant increases in the plasma concentration of A·− were detected in the peripheral blood of patients (normoxia(baseline) vs 6 data points of reperfusion after 5min of global ischaemic condition, P<0.05),(baseline vs immediate after ischaemia; 2337±525 vs 2633±508, AU, respectively). During global ischaemia the regional muscle oxygenation significantly decreased (↓∆O2Hb-oxyhaemoglobin), ↑∆HHb- deoxyhaemoglobin ), although increased regional blood volume (↑∆tHb- total haemoglobin). From the end of global ischaemia to 10 min after the regional muscle oxygenation progressively back to the start data point (↓∆HHb, ↑∆O2Hb). This study demonstrates for the first time that the I-R has got a big influence on the muscle oxygenation to increased ROS and the return of values towards baseline period in reperfusion stage appears to coincide with increased oxidative stress. Moreover, the present study has also demonstrated increased A·− level as early as the ischaemic phase of experiment independent of perioperative changes in the partial pressure of oxygen (pO2), elucidate a potentially important role for oxidative stress in provoking an appropriate vasodilation (NO-bioavailability) during the I-R period. This work demonstrates that; - Ascorbate is an antioxidant that can scavenge tissue and blood borne free radical, is essential in controlled amounts and is capable of initiating protective adaptation in the face of oxidative stress for the maintenance of physiological homeostasis. - Reperfusion is always associated with a sudden and massive release of ascorbate free radicals, with a maximal liberation within the first minutes of reperfusion. Vitamin C tended to reduce infarct size and protects from oxidative damage during global ischaemia and reperfusion. - The venous cannulation alone is enough per se stimulates the systemic formation of free radicals as a acute phase response. If this baseline artefact is not taken into account, the true magnitude of the exercise-induced oxidative stress response will be under-estimated.
The I-R has got a major influence on the muscle oxygenation to increased ROS and the return of values towards baseline period in reperfusion stage appears to coincide with increased oxidative stress. Using the state-of-the-art molecular techniques that include Electron Paramagnetic Spectroscopy (EPR) for the direct detection of free radicals and Near Infrared Spectroscopy (NIRS) for the direct detection of muscle oxygenation these studies have attempted to translate the basic mechanisms associated with free radical formation during I-R and have provided unique insight into the basic mechanisms responsible for the oxidative stress with the ultimate objective of developing novel antioxidant interventions that can provide effective prophylaxis.

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Sun, Zhenning. "Studies on fluorescent probes for the specific detection of reactive oxygen species and reactive nitrogen species in living cells". View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36845395.

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Gabe, Atsushi. "Understanding of Carbon Active Sites for Oxygen Reduction Reaction". Doctoral thesis, Universidad de Alicante, 2018. http://hdl.handle.net/10045/87127.

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Este trabajo de Tesis Doctoral se ha centrado en comprender el comportamiento de electrocatalizadores basados en materiales carbonosos para la reacción de reducción de oxígeno. Con el fin de profundizar en el conocimiento de la naturaleza de los sitios activos de catalizadores basados en materiales carbonosos para esta reacción, se han seleccionado o preparado muestras con diferentes composiciones, texturas porosas y estructuras. De estos resultados se han conseguido importantes avances en el conocimiento del papel que los sitios activos de catalizadores basados en materiales carbonosos desempeñan en dicha reacción. Estos conocimientos y los materiales derivados pueden utilizarse en el desarrollo de cátodos para pilas de combustible en medio alcalino.
Heiwa Nakajima Foundation

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Johansson, Kristin. "Oxygen-reducing enzymes in coatings and films for active packaging". Doctoral thesis, Karlstads universitet, Institutionen för ingenjörs- och kemivetenskaper, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-28749.

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Oxygen scavengers are used in active packages to protect the food against deteriorative oxidation processes. The aim of this work was to investigate the possibilities to produce oxygen-scavenging packaging materials based on oxygen-reducing enzymes. The enzymes were incorporated into a dispersion coating formulation applied onto a food-packaging board using conventional laboratory coating techniques. Various enzymes were used: a glucose oxidase, an oxalate oxidase and three laccases originating from different organisms. All of the enzymes were successfully incorporated into a coating layer and could be reactivated after drying. For at least two of the enzymes, re-activation was possible not only by using liquid water but also by using water vapour. Re-activation of the glucose oxidase and a laccase required relative humidities of greater than 75% and greater than 92%, respectively. Catalytic reduction of oxygen gas by glucose oxidase was promoted by creating an open structure through addition of clay to the coating at a level above the critical pigment volume concentration. Migration of the enzyme and the substrate was reduced by adding an extrusion-coated liner of polypropylene on top of the coating. For the laccase-catalysed reduction of oxygen it was possible to use lignin derivatives as substrates for the enzymatic reaction. The laccase-catalysed reaction created a polymeric network by cross-linking of lignin-based entities, which resulted in increased stiffness and increased water-resistance of biopolymer films. The laccases were also investigated with regard to their potential to function as oxygen scavengers at low temperatures. At 7°C all three laccases retained more than 20% of the activity they had at room temperature (25°C), which suggests that the system is also useful for packaging of refrigerated food.

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Wu, Wan Man. "Reactive oxygen species and murine malaria". Thesis, The University of Sydney, 1992. https://hdl.handle.net/2123/26446.

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The aim of this study was to investigate the role of ROS in the protective and pathological immune response during malarial infection. For this purpose, four isolates of Plasmodium parasites (P. berghei ANKA, P. vinckei, P. berghei K152 and P. chabaudi) and two different inbred strains of mice (CBA and DBA) were used. The patterns of mortality varied between the different mouseparasite strain combinatio ns. The mortality of CBA mice infected with P. vinckei and P. berghei K152, and DBA mice infected with P. berghei ANKA, related to the levels of parasitaemia. However early mortality of CBA mice infected with P. berghei ANKA did not relate to the parasitaem ia level but to the onset of neurologica l symptoms. Over 90% of P. chabaudi—infected CBA mice recovered from the infection. The morphologi cal examinatio n of brain tissues obtained from P. berghei ANKA-infec ted CBA mice on day 7 post-inocul ation showed haemorrag e, oedema and the infiltration of mononucle ar cells. Measurement of the permeability of the blood-brain barrier by injection of Evans blue showed the dye leaking into the brain parenchyma, suggesting a dysfunction of the barrier in this mouse model. The hypothesis that ROS play a role in the anti—malaria response was supported by previous studies demonstrati ng that malaria parasites are killed by ROS in vivo and in vitro (reviewed in Hunt & Stocker. 1990). To further test the hypothesis. the oxidative burst ability of splenic macrophage s and peripheral monocytes taken from different mouse-para site strain combinations was examined. There was a significant increase of superoxide production by splenic macrophag es at the early stage of all the infections and the spleen weight gradually increased during all the infections. Furthermore, the oxidative burst ability of monocytes was significantly increased in the late stage of all the infections, which was accompanied by increased peripheral WBC numbers, especially in the numbers of monocytes and PMNs in all the infections except the P. berghei ANKA infection in CBA mice. Of the four strains of parasites infecting CBA mice, the self-resol ving P. Chabaudi infection induced the greatest PMA-stimulable response superoxide anion production on certain days after parasite in inoculation in both splenic macrophages and monocytes . Conversely, the P. vinckei infection induced the lowest response, which may partly explain why the parasites generated faster in these mice than in the other three strains. Malaria parasites are able to induce immunosup pression at the early stage of infection as shown by the decline in the total number of WBC and the decrease of superoxide production by monocytes. This immunosuppresion may help explain why the parasites can survive even when their numbers are. small. TNF and IFN—y are known as major mediatory factors involved in the development of cerebral malaria. This was supported by the cytokine gene expression studies which showed that both TNF and IFN-y mRNAs were expressed in the brains of mice with cerebral malaria. These cytokines may stimulate mononuclear phagocytes to produce other soluble factors to cause cerebral damage. ROS release d from mononuclear phagocytes are thought to be crucial factors involved in the development of cerebral malaria (Hunt et al., 1991). However , the oxidative burst ability of splenic macrophages and monocytes in the P. berghei—ANKA infected CBA mice, which suffered cerebral malaria and died early in the infection, was lower than that in the same infection in DBA mice which recovered from the cerebral lesion but died at a later stage of infection with a high level of parasitaemia. Further more, lipid peroxidation studies showed that there was no significant difference in brain MDA formation between control mice and the mice with cerebral malaria . These results fail to provide evidence for a role of ROS in the development of cerebral malaria . Further studies to investigate lipid peroxidation and redox. status of the brain in cerebral malaria using HPLC are required.

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Sun, Zhenning, e 孫振宁. "Studies on fluorescent probes for the specific detection of reactive oxygen species and reactive nitrogen species in living cells". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B38677490.

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Peng, Tao, e 彭濤. "Rhodol fluorophores and fluorescent probes for the detection and imaging of reactive oxygen species". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B41757920.

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Peng, Tao. "Rhodol fluorophores and fluorescent probes for the detection and imaging of reactive oxygen species". Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B41757920.

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Mahajan, Kamal. "Synthesis and Characterization of New Active Barrier Polymers". University of Toledo / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1271339021.

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Rentel, Maike Christina. "Signal transduction in response to active oxygen species in Arabidopsis thaliana". Thesis, University of Oxford, 2002. http://ora.ox.ac.uk/objects/uuid:5dc0b7f5-5aa9-4633-a8dd-89ca2dcb3982.

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Many environmental stresses result in increased generation of active oxygen species (AOS) in plant cells, leading to the induction of protective mechanisms. In this study, signalling components linking AOS perception to downstream responses were examined, with particular emphasis on H₂O₂ signalling. All AOS investigated had an early [Ca²⁺]_cyt peak in common, but differed in other aspects of their Ca²⁺ signatures, indicating that the plant is able to discriminate between different types of AOS. An early event in AOS signal transduction may involve changes in the cellular redox balance as reduction of glutathione levels prior to stress application increased the height of the first [Ca²⁺]_cyt peak. Inhibiting or enhancing the height of the H₂O₂-triggered Ca²⁺ signature lead to inhibition or enhancement of GST1 and APX1 induction, respectively, demonstrating that the Ca²⁺ signature is required for induction of genes encoding antioxidant enzymes. OX1, encoding a putative ser/thr kinase, was shown to be involved in signal transduction in response to H₂O₂-generating stresses. Transcript levels of OX1 were increased upon treatment with H₂O₂ and a range of abiotic and biotic stresses as well as ABA, all of which have been shown to result in H₂O₂ accumulation. Inhibition of stress-induced [Ca²⁺]_cyt elevations inhibited OX1 induction, placing the OX1 kinase downstream of Ca²⁺ in the signalling chain. OX1 is required for full activation of AtMPKS and AtMPK6 in response to ozone fumigation, indicating that OX1 functions upstream of these MAP kinases. An ox1 null-mutant displayed enhanced susceptibility to infection with a virulent Peronospora parasitica isolate as well as reduced induction of several defence genes. In addition, the ox1 mutant exhibited shorter root hairs and an early flowering phenotype. AOS treatment induced several genes encoding AtERF transcription factors, but did not have an effect on other members of this family. Induction occurred in an ethylene-independent but Ca²⁺-dependent manner.

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Più fonti

Libri sul tema "Active oxygen"

Valentine, Joan Selverstone, Christopher S. Foote, Arthur Greenberg e Joel F. Liebman, a cura di. Active Oxygen in Biochemistry. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0609-2.

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Valentine, Joan Selverstone, Christopher S. Foote, Arthur Greenberg e Joel F. Liebman, a cura di. Active Oxygen in Biochemistry. Boston, MA: Springer US, 1995. http://dx.doi.org/10.1007/978-1-4613-9783-0.

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Foote, Christopher S., Joan Selverstone Valentine, Arthur Greenberg e Joel F. Liebman, a cura di. Active Oxygen in Chemistry. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-007-0874-7.

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S, Foote Christopher, a cura di. Active oxygen in chemistry. London: Blackie Academic & Professional, 1995.

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1946-, Bachmanova G. I., a cura di. Cytochrome P-450 and active oxygen. London: Taylor & Francis, 1990.

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Atanu, Barik, e Bhabha Atomic Research Centre, a cura di. Singlet oxygen.: Photosensitized generation, detection, and reaction with organic molecules. Mumbai: Bhabha Atomic Research Centre, 2006.

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Kunio, Yagi, a cura di. Oxygen radicals. Amsterdam: Excerpta Medica, 1992.

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W, Allen Henry, e Culbert Michael L. 1937-, a cura di. Oxidology: The study of reactive oxygen toxic species (ROTS) and their metabolism in health and disease : the ROTS theory of degenerative disease and the HLB blood test. Los Altos, Calif: R.W. Bradford Foundation, 1985.

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L, Gilbert Daniel, e Colton Carol A, a cura di. Reactive oxygen species in biological systems: An interdisciplinary approach. New York: Kluwer Academic/Plenum Publishers, 1999.

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International, Conference on Oxygen and Life (3rd 2000 Kyoto Japan). Oxygen and life: Oxygenases, oxidases, and lipid mediators : proceedings of the 3rd International Conference on Oxygen and Life which was held in Kyoto, between 26 and 29 November 2000. Amsterdam: Elsevier, 2002.

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Capitoli di libri sul tema "Active oxygen"

Iversen, Patrick L. "Active Oxygen Defenses". In Molecular Basis of Resilience, 195–222. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-98164-2_9.

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Aust, Steven D., Craig E. Thomas, Lee A. Morehouse, Morio Saito e John R. Bucher. "Active Oxygen and Toxicity". In Biological Reactive Intermediates III, 513–26. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4684-5134-4_49.

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Cerutti, Peter A. "Active Oxygen and Promotion". In Arachidonic Acid Metabolism and Tumor Promotion, 131–68. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2605-2_7.

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Ho, Raymond Y. N., Joel F. Liebman e Joan Selverstone Valentine. "Overview of the Energetics and Reactivity of Oxygen". In Active Oxygen in Chemistry, 1–23. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-007-0874-7_1.

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Walling, Cheves. "Autoxidation". In Active Oxygen in Chemistry, 24–65. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-007-0874-7_2.

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Bielski, Benon H. J., e Diane E. Cabelli. "Superoxide and Hydroxyl Radical Chemistry in Aqueous Solution". In Active Oxygen in Chemistry, 66–104. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-007-0874-7_3.

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Foote, Christopher S., e Edward L. Clennan. "Properties and Reactions of Singlet Dioxygen". In Active Oxygen in Chemistry, 105–40. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-007-0874-7_4.

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Dussault, Pat. "Reactions of Hydroperoxides and Peroxides". In Active Oxygen in Chemistry, 141–203. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-007-0874-7_5.

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Ebner, Jerry, e Dennis Riley. "Catalytic Oxidations with Oxygen: An Industrial Perspective". In Active Oxygen in Chemistry, 204–48. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-007-0874-7_6.

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Atkinson, Roger. "Reactions of Oxygen Species in the Atmosphere". In Active Oxygen in Chemistry, 249–79. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-007-0874-7_7.

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Atti di convegni sul tema "Active oxygen"

Matsumoto, Hiroyuki, Mikihiko Matsuoka e Kazutoshi Noda. "Active oxygen detection using Quartz Crystal Microbalance method under inductively coupled oxygen plasma". In 2008 International Conference on Control, Automation and Systems (ICCAS). IEEE, 2008. http://dx.doi.org/10.1109/iccas.2008.4694461.

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Rawlins, Wilson T., Seonkyung Lee e Steven J. Davis. "Production of metastable singlet oxygen in the reaction of nitric oxide with active oxygen". In Lasers and Applications in Science and Engineering, a cura di Steven J. Davis, Michael C. Heaven e J. Thomas Schriempf. SPIE, 2008. http://dx.doi.org/10.1117/12.773783.

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Kulagin, Yuri A., e Victoria N. Yarygina. "Analysis of rate constants for oxygen-iodine active media". In Fourth International Workshop on Iodine Lasers and Applications, a cura di Karel Rohlena, Jarmila Kodymova e Bozena Kralikova. SPIE, 1996. http://dx.doi.org/10.1117/12.232188.

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Ono, Yumie, Mikie Nakabayashi e Masashi Ichinose. "Diffuse Optics for Probing Oxygen Metabolism of Active Muscles". In 2021 IEEE Photonics Conference (IPC). IEEE, 2021. http://dx.doi.org/10.1109/ipc48725.2021.9592861.

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Xu, Zi-Qiang, Simon Ang, Marzia Zaman, Shaowei He, Si Huang e Hong Xia. "Structure design and process improvement of planar oxygen sensor". In 2016 13th International Computer Conference on Wavelet Active Media Technology and Information Processing (ICCWAMTIP). IEEE, 2016. http://dx.doi.org/10.1109/iccwamtip.2016.8079884.

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Kolobyanin, Yuriy, Yuriy Adamenkov, Boris Vyskubenko, Leonid Goryachev, Sergey Ilyin, Anatoliy Kalashnik, Tatiana Rakhimova e Georgiy Rogozhnikov. "Active medium gain study of electric-discharge oxygen-iodine laser". In XVI International Symposium on Gas Flow, Chemical Lasers, and High-Power Lasers. SPIE, 2006. http://dx.doi.org/10.1117/12.739082.

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Kääriäinen, Teemu, e Jeremias Seppä. "Active 3D camera based on laser absorption of molecular oxygen". In 3D Image Acquisition and Display: Technology, Perception and Applications. Washington, D.C.: Optica Publishing Group, 2023. http://dx.doi.org/10.1364/3d.2023.jth1a.4.

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We present a novel method for 3D imaging, based on laser light absorption by atmospheric oxygen. The camera uses a current tunable distributed feedback laser for illumination and a silicon-based CMOS camera for imaging.

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Kryachkova, N. V., A. A. Polyakova, M. M. Biryukov, E. V. Milakhina, D. E. Zakrevsky, I. V. Schweigert e O. A. Koval. "CYTOSTATIC EFFECT OF COLD PLASMA JET ON HUMAN TUMOR CELLS". In X Международная конференция молодых ученых: биоинформатиков, биотехнологов, биофизиков, вирусологов и молекулярных биологов — 2023. Novosibirsk State University, 2023. http://dx.doi.org/10.25205/978-5-4437-1526-1-339.

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Cold plasma activates various processes when acting on biomolecules, including tumors. Сold plasma jet (CPJ) generates active forms of oxygen and nitrogen, and such species cause oxidative stress. This study shows an increase in active forms of nitrogen in irradiated A549 tumor cells compared to healthy Wi-38 cells. The action of CPJ on tumor cells causes cell cycle arrest, and suppresses their proliferation.

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Tolstov, Georgy, Marsel Zagidullin, Nikolay Khvatov, Yakov Medvedkov e Paul Mikheyev. "O2(bΣ1+g) relaxation in active medium of oxygen-iodine laser". In Saratov Fall Meeting 2017: Fifth International Symposium on Optics and Biophotonics: Laser Physics and Photonics XIX; Computational Biophysics and Analysis of Biomedical Data IV, a cura di Vladimir L. Derbov e Dmitry E. Postnov. SPIE, 2018. http://dx.doi.org/10.1117/12.2315801.

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Kaminski, Pawel, Roman Kozlowski e Andrzej Misiuk. "Electrically active defects in Ni-contaminated Cz-Si with oxygen precipitates". In Metal/Nonmetal Microsystems: Physics, Technology, and Applications, a cura di Benedykt W. Licznerski e Andrzej Dziedzic. SPIE, 1996. http://dx.doi.org/10.1117/12.238141.

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Rapporti di organizzazioni sul tema "Active oxygen"

Nikolla, Eranda. Final Report: Nanostructured, Targeted Layered Metal Oxides as Active and Selective Heterogeneous Electrocatalysts for Oxygen Electrocatalysis. Office of Scientific and Technical Information (OSTI), gennaio 2021. http://dx.doi.org/10.2172/1763600.

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Lashier, M. An investigation of active and selective oxygen in vanadium phosphorus oxide catalysts for n-butane conversion to maleic anhydride. Office of Scientific and Technical Information (OSTI), gennaio 1990. http://dx.doi.org/10.2172/6944921.

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Elmann, Anat, Orly Lazarov, Joel Kashman e Rivka Ofir. therapeutic potential of a desert plant and its active compounds for Alzheimer's Disease. United States Department of Agriculture, marzo 2015. http://dx.doi.org/10.32747/2015.7597913.bard.

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We chose to focus our investigations on the effect of the active forms, TTF and AcA, rather than the whole (crude) extract. 1. To establish cultivation program designed to develop lead cultivar/s (which will be selected from the different Af accessions) with the highest yield of the active compounds TTF and/or achillolide A (AcA). These cultivar/s will be the source for the purification of large amounts of the active compounds when needed in the future for functional foods/drug development. This task was completed. 2. To determine the effect of the Af extract, TTF and AcA on neuronal vulnerability to oxidative stress in cultured neurons expressing FAD-linked mutants.Compounds were tested in N2a neuroblastoma cell line. In addition, we have tested the effects of TTF and AcA on signaling events promoted by H₂O₂ in astrocytes and by β-amyloid in neuronal N2a cells. 3. To determine the effect of the Af extract, TTF and AcA on neuropathology (amyloidosis and tau phosphorylation) in cultured neurons expressing FAD-linked mutants. 4. To determine the effect of A¦ extract, AcA and TTF on FAD-linked neuropathology (amyloidosis, tau phosphorylation and inflammation) in transgenic mice. 5. To examine whether A¦ extract, TTF and AcA can reverse behavioral deficits in APPswe/PS1DE9 mice, and affect learning and memory and cognitive performance in these FAD-linked transgenic mice. Background to the topic.Neuroinflammation, oxidative stress, glutamate toxicity and amyloid beta (Ab) toxicity are involved in the pathogenesis of Alzheimer's diseases. We have previously purified from Achilleafragrantissimatwo active compounds: a protective flavonoid named 3,5,4’-trihydroxy-6,7,3’-trimethoxyflavone (TTF, Fl-72/2) and an anti-inflammatory sesquiterpenelactone named achillolide A (AcA). Major conclusions, solutions, achievements. In this study we could show that TTF and AcA protected cultured astrocytes from H₂O₂ –induced cell death via interference with cell signaling events. TTF inhibited SAPK/JNK, ERK1/2, MEK1 and CREBphosphorylation, while AcA inhibited only ERK1/2 and MEK1 phosphorylation. In addition to its protective activities, TTF had also anti-inflammatory activities, and inhibited the LPS-elicited secretion of the proinflammatorycytokinesInterleukin 6 (IL-6) and IL-1b from cultured microglial cells. Moreover, TTF and AcA protected neuronal cells from glutamate and Abcytotoxicity by reducing the glutamate and amyloid beta induced levels of intracellular reactive oxygen species (ROS) and via interference with cell signaling events induced by Ab. These compounds also reduced amyloid precursor protein net processing in vitro and in vivo in a mouse model for Alzheimer’s disease and improvedperformance in the novel object recognition learning and memory task. Conclusion: TTF and AcA are potential candidates to be developed as drugs or food additives to prevent, postpone or ameliorate Alzheimer’s disease. Implications, both scientific and agricultural.The synthesis ofAcA and TTF is very complicated. Thus, the plant itself will be the source for the isolation of these compounds or their precursors for synthesis. Therefore, Achilleafragrantissima could be developed into a new crop with industrial potential for the Arava-Negev area in Israel, and will generate more working places in this region.

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Barker, Amanda, Taylor Sullivan, W. Baxter, Robyn Barbato, Shawn Gallaher, Grace Patton, Joseph Smith e Thomas Douglas. Iron oxidation–reduction processes in warming permafrost soils and surface waters expose a seasonally rusting Arctic watershed. Engineer Research and Development Center (U.S.), giugno 2024. http://dx.doi.org/10.21079/11681/48714.

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Landscape-scale changes from climate change in the Arctic affect the soil thermal regime and impact the depth to permafrost in vulnerable tundra watersheds. When top-down thaw of permafrost occurs, oxygen and porewaters infiltrate deeper in the soil column exposing fresh, previously frozen material and altering redox conditions. A gap remains in understanding how redox stratifications in thawing permafrost impact the geochemistry of watersheds in response to climate change and how investigations into redox may be scaled by coupling extensive geophysical mapping techniques. In this study, we collected soils and soil porewaters from three soil pits and surface water samples from an Arctic watershed on the North Slope of Alaska and analyzed for trace metals iron (Fe) and manganese (Mn) and Fe oxidation state using bulk and microscale techniques. We also used geophysical mapping and soil thermistors to measure active layer depths across the watershed to relate accelerating permafrost thaw to watershed geochemistry. Overall, evidence showed that Fe and Mn could be useful as geochemical indicators of permafrost thaw and release of Fe(II) from thawing permafrost and further oxidation to Fe(III) could translate to a higher degree of seasonal rusting coinciding with the warming and thawing of near surface-permafrost.

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Morris, Andrew M., Peter Juni, Ayodele Odutayo, Pavlos Bobos, Nisha Andany, Kali Barrett, Martin Betts et al. Remdesivir for Hospitalized Patients with COVID-19. Ontario COVID-19 Science Advisory Table, maggio 2021. http://dx.doi.org/10.47326/ocsat.2021.02.27.1.0.

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Remdesivir, a direct-acting antiviral agent, may reduce mortality and progression to mechanical ventilation in moderately ill patients hospitalized with COVID-19 on supplemental low-flow oxygen. The benefits of remdesivir for critically ill patients requiring supplemental oxygen via high-flow nasal cannula or mask, or non-invasive mechanical ventilation, is uncertain. Remdesivir does not benefit and may harm critically ill patients already receiving mechanical ventilation or requiring extra-corporeal membrane oxygenation (ECMO), and it does not provide substantial benefit for hospitalized patients who do not require supplemental oxygen. Remdesivir appears to have comparable effects when used for 5 days or 10 days, and does not appear to be associated with significant adverse effects. Remdesivir is recommended in moderately ill hospitalized patients with COVID-19 requiring supplemental oxygen (Figure 1). Remdesivir may be considered for patients requiring oxygen supplementation via high-flow nasal cannula or mask, or non-invasive mechanical ventilation. It should not be used in critically ill patients on mechanical ventilation or those receiving ECMO. Remdesivir should not be used in patients who do not require supplemental oxygen.

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Rossi, Ruggero, David Jones, Jaewook Myung, Emily Zikmund, Wulin Yang, Yolanda Alvarez Gallego, Deepak Pant et al. Evaluating a multi-panel air cathode through electrochemical and biotic tests. Engineer Research and Development Center (U.S.), dicembre 2022. http://dx.doi.org/10.21079/11681/46320.

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To scale up microbial fuel cells (MFCs), larger cathodes need to be developed that can use air directly, rather than dissolved oxygen, and have good electrochemical performance. A new type of cathode design was examined here that uses a “window-pane” approach with fifteen smaller cathodes welded to a single conductive metal sheet to maintain good electrical conductivity across the cathode with an increase in total area. Abiotic electrochemical tests were conducted to evaluate the impact of the cathode size (exposed areas of 7 cm², 33 cm², and 6200 cm²) on performance for all cathodes having the same active catalyst material. Increasing the size of the exposed area of the electrodes to the electrolyte from 7 cm² to 33 cm² (a single cathode panel) decreased the cathode potential by 5%, and a further increase in size to 6200 cm² using the multi-panel cathode reduced the electrode potential by 55% (at 0.6 A m⁻²), in a 50 mM phosphate buffer solution (PBS). In 85 L MFC tests with the largest cathode using wastewater as a fuel, the maximum power density based on polarization data was 0.083 ± 0.006Wm⁻² using 22 brush anodes to fully cover the cathode, and 0.061 ± 0.003Wm⁻² with 8 brush anodes (40% of cathode projected area) compared to 0.304 ± 0.009Wm⁻² obtained in the 28 mL MFC. Recovering power from large MFCs will therefore be challenging, but several approaches identified in this study can be pursued to maintain performance when increasing the size of the electrodes.

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Siegel, David A., Ivona Cetinic, Andrew F. Thompson, Norman B. Nelson, Michaela Sten, Melissa Omand, Shawnee Traylor et al. EXport Processes in the Ocean from RemoTe Sensing (EXPORTS) North Atlantic sensor calibration and intercalibration documents. NASA STI Program and Woods Hole Oceanographic Institution, ottobre 2023. http://dx.doi.org/10.1575/1912/66998.

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The following documents collect information regarding the calibration and intercalibration of various sensors that were deployed during the North Atlantic field component of the NASA EXPORTS project (EXPORTS NA), which took place between May 4 and June 1, 2021 (Johnson et al., 2023). The EXPORTS NA campaign was designed to to provide a contrasting end member to the earlier North Pacific field campaign, and focused on carbon export associated with the North Atlantic spring bloom in which gravitational sinking of organic particles, the physical advection and mixing, and active transport by vertically migrating zooplankton are all expected to provide significant flux pathways. During EXPORTS NA data sets were collected from a variety of shipbased, autonomously-piloted, and Lagrangian platforms. Intercalibration activities were tasked to different groups within the EXPORTS project team. Team leads and contact information are listed below. The overarching goal of these activities was to identify a trusted sensor, carry out a careful calibration of this sensor, then base any intercalibraiton needs off of this sensor, occasionally propagating information across platforms. Full details of the intercalibration approach, assumptions, and summary are provided in the attached documents. All calibration and intercalibration activities were completed before data set were uplaoded to the NASA SeaBASS data repository. Data related to this cruise can be publicly accessed at: https://seabass.gsfc.nasa.gov/cruise/EXPORTSNA Updates to calibration and intercalibration documents required to reflect revised data sets will also be provided through SeaBASS. Questions concerning referencing these documents or accessing data sets should be directed to Inia Soto Ramos. NASA EXPORTS Science Lead: David Siegel, davesiegel@ucsb.edu NASA EXPORTS Project Scientist: Ivona Cetini´c, ivona.cetinic@nasa.gov NASA EXPORTS Data Manager: Inia Soto Ramos, inia.m.sotoramos@nasa.gov Calibration and intercalibration leads Temperature and salinity sensors: Andy Thompson, andrewt@caltech.edu Chlorophyll fluorescence sensors: Melissa Omand & Kaley Sten, momand@uri.edu Oxygen sensors: Shawnee Traylor & Roo Nicholson, shawnee@mit.edu Optical backscatter sensors: Xiaodong Zhang, Xiaodong.Zhang@usm.edu Lagrangian float sensors: Eric D’Asaro, dasaro@apl.washington.edu Underway sensors: Leah Johnson, leahjohn@uw.edu Underwater Vision Profiler (UVP)-Particle Size Distribution (PSD): David Siegel, davesiegel@ucsb.edu

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Weissinger, Rebecca. Status and trends of springs at Hovenweep National Monument, 1999–2021. A cura di Alice Wondrak Biel. National Park Service, agosto 2023. http://dx.doi.org/10.36967/2294373.

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Water is a scarce, but vital, resource at Hovenweep National Monument (NM). The National Park Service has prioritized long-term monitoring of water resources at the monument through a variety of programs and indicators since 1999. The purpose of this report is to evaluate water-quantity and water-quality data collected at long-term monitoring sites in Hovenweep NM from 1999 to 2021 for trends over time, and to summarize site-characterization data for currently monitored locations. Data are available for three active monitoring stations—Square Tower Spring, Hackberry Pool, and Goodman Point Spring—and three discontinued monitoring stations—Cajon Pool, Upper Hackberry Spring (Spring #4), and Horseshoe Spring. Water resources at Hovenweep NM have exhibited many trends over the past two decades. Pool levels at both Square Tower Spring and Hackberry Pool went up, with a step increase shown in 2016 (after no sampling in 2014–2015). In contrast, flow decreased by more than half at Goodman Point Spring and ceased at Upper Hackberry Spring (Spring #4). Flow at Horseshoe Spring also decreased, although the period of record at this site was very short. Both Upper Hackberry Spring (Spring #4) and Horseshoe Spring were removed from the monitoring rotation because flows were increasingly absent or too low to measure. Pool-level dynamics and water chemistry at Cajon Pool are characteristic of precipitation-derived water rather than groundwater; this site was removed from the monitoring rotation because it was not a good indicator of groundwater conditions. The water chemistry in both Square Tower Spring and Hackberry Pool changed significantly, but in opposite directions. Square Tower Spring had increasing total dissolved solids (TDS) and specific conductance, with all major ions showing increases over time. Hackberry Pool had decreases in TDS and most major ions through 2010, when water-chemistry lab analyses were suspended due to logistical constraints. Specific conductance continued to decrease at Hackberry Pool through 2021. The reasons for these changes are unknown. Increases in major ions at Square Tower Spring are unlikely to be related to oil and gas development in the region. Decreases in major ions at Hackberry Pool may reflect an increase in the amount of water that is entering the pool from rain and snowmelt rather than groundwater at this site. Water-quality parameters at Goodman Point Spring have remained stable. While the causes of trends in water chemistry at these sites are likely natural, the small quantities of water and harsh water-quality conditions make these sites poor habitat for aquatic life. Groundwater is naturally low in dissolved oxygen—but the dissolved-oxygen concentrations in the two pools are persistently low, sometimes falling to near zero in the summer. Water temperatures also warm in conjunction with air temperatures, with temperatures as warm as 18°C in the pools and 19°C in Goodman Point Spring. Traditionally, Puebloan cultures would have managed these small water resources to promote infiltration and retention of precipitation and to remove sediment and debris. Decreases in flow and increasing vegetation stress are likely tied to increasing air temperatures and long-term drought conditions across the region. The namesake hackberry trees at Hackberry Pool and nearby sites have shown increasing drought stress. Regionally, the underlying Dakota aquifer that feeds springs at the monument was relatively stable from 2008 to 2017, with decreasing levels from 2018 to 2021. Overall, the most concerning trends observed at springs in Hovenweep NM are likely due to climate change. Increasing air temperature threatens springflow and spring-associated vegetation through increased evapotranspiration. While pool levels have increased, recent decreases in the regional Dakota aquifer raise concerns about the stability of pools in the future. Managers could consider the potential benefits and risks of: Prioritizing protections and actions at Square Tower Spring, which has been the most resilient site at the monument in persistence of surface water and vegetation health during extreme drought. Implementing potential climate-adaptation actions that could improve groundwater infiltration upgradient of spring sites. This could include rehabilitating traditional structures to slow the flow of surface water. Implementing traditional management techniques that could increase dissolved-oxygen concentrations in the spring pools. Increasing invasive-plant removal efforts at Goodman Point Spring, which had the greatest number and cover of invasive-plant species of the three currently monitored locations. Developing interpretive stories about water-management techniques and the role of climate change in creating drought stress on iconic hackberry trees.

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Pesis, Edna, Elizabeth J. Mitcham, Susan E. Ebeler e Amnon Lers. Application of Pre-storage Short Anaerobiosis to Alleviate Superficial Scald and Bitter Pit in Granny Smith Apples. United States Department of Agriculture, gennaio 2013. http://dx.doi.org/10.32747/2013.7593394.bard.

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There is increased demand for high quality fruit produced and marketed with reduced chemical inputs to minimize toxic effects on human health and the environment. Granny Smith (GS) apple quality is reduced by two major physiological disorders, superficial scald and bitter pit (BP). These disorders cause great loss to apple growers worldwide. Superficial scald is commonly controlled by chemical treatments, mainly the antioxidant diphenylamine (DPA) and/or the ethylene action inhibitor, 1-methylcyclopropene (1–MCP). Both chemicals are ineffective in controlling bitter pit incidence. We proposed to investigate the beneficial use of non-chemical, abiotic stress with low O2 (LO2) applied for 10d at 20°C on GS apple fruit. During the project we expanded the treatment to more apple cultivars, Golden Delicious (GD) and Starking Delicious (SD) and another pome fruit, the pear. Apple and pear have similar physiological disorders that develop during cold storage and we examined if the LO2 treatment would also be effective on pear. Application of 0.5% LO2 atmosphere for 10d at 20°C or 500ppb 1-MCP at 20°C prior to cold storage at 0°C, was effective in reducing superficial scald in GS apple. Moreover, LO2 pretreatment was also effective in reducing bitter pit (BP) development in California GS and Israeli GD and SD apples The BP symptoms in GS from California were much more prominent, so the effect of LO2 was more dramatic than the effect on the Israeli cvs. GD and SD, nevertheless the LO2 treatment showed the same trend in all cultivars in reducing BP. The LO2 and 1-MCP -treated fruit exhibited lower levels of ethylene, - farnesene and its oxidation product, 6-methyl-5-hepten-2-one (MHO), as determined by SPME/GC-MS analysis. In addition, LO2 pretreatment applied to California Bartlett or Israeli Spadona pears was effective in reducing superficial scald, senescent scald and internal breakdown after 4 m of cold storage at 0°C. For GS apple, low-temperature storage resulted in oxidative stress and chilling injury, caused by increased production of superoxide anions which in turn led to the generation of other dangerous reactive oxygen species (ROS). Using confocal laser-scanning microscopy and H2O2 measurements of apple peel, we observed ROS accumulation in control fruit, while negligible amounts were found in LO2 and 1-MCP treated fruit. Gene-expression levels of ROS-scavenging enzymes were induced by the various pretreatments: catalase was induced by LO2 treatment, whereas Mn superoxide dismutase was induced by 1-MCP treatment. We assume that LO2 and 1-MCP pretreated fruit remained healthier due to reduced production of ethylene and reactive oxygen substances, such as MHO, during cold storage. The LO2-treated apple exhibited greener peel and firmer fruit after 6 m of cold storage, and the fruit had high crispiness leading to high taste preference. In both pear cultivars, the LO2 treatment led to a reduction in internal breakdown and browning around the seed cavity. We tested the LO2 pre-storage treatment on a semi-commercial scale that would be applicable to a small organic grower by sealing the fruit within the plastic field bins. The treatment was most effective with a continuous flow of nitrogen through the bins; however, a single 6 hour flush of nitrogen was also fairly effective. In addition, we determined that it was very important to have the oxygen levels below 0.5% for approximately 10 days to achieve good scald control, not counting the time required to reduce the oxygen concentration. Our LO2 technology has been proven in this project to be effective in reducing several physiological disorders developed in pome fruit during cold storage. We hope that our non-chemical treatment which is friendly to the environment will be used in the near future for the organic apple and pear industry. The next step should be an analysis of the cost-benefits and commercial feasibility.

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Azzi, Elias S., Cecilia Sundberg, Helena Söderqvist, Tom Källgren, Harald Cederlund e Haichao Li. Guidelines for estimation of biochar durability : Background report. Department of Energy and Technology, Swedish University of Agricultural Sciences, 2023. http://dx.doi.org/10.54612/a.lkbuavb9qc.

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Biochar is produced by heating biomass in the total or partial absence of oxygen. This report addresses the long-term persistence of biochar in soil and how this can be managed in climate calculations and reporting. The report consists of this summary and four chapters, which can be read independently. Different terms have been used to describe the durability of biochar carbon storage, but also the physical presence of biochar in soils, e.g. persistence, permanence, recalcitrance, residence times, stability. Today, the term “durability of carbon storage” is preferred in policy contexts, but various academic disciplines such as soil science have other established terms like “persistence”. Here, both durability and persistence are used, rather interchangeably. It is important to be aware of differences in meaning that exist between disciplines. The purpose of this report is to present the state of knowledge regarding the proportion of carbon in biochar that remains in the soil over time and provide recommendations for calculating this. There is a need to calculate the persistence of biochar in soil for national climate reporting, corporate climate reporting, carbon credit trading, and life cycle assessments for various purposes. On the persistence of biochar The amount of biochar remaining after a certain time depends on the properties of the biochar and the environment in which it is located. Nearly all research on biochar persistence has focused on its application in agricultural soils. The main reason for the high durability of biochar carbon storage is the formation of fused aromatic stable structures during biomass pyrolysis. A high degree of fused aromatic structures makes biochar much less prone to microbial decomposition than fresh biomass. Different biochars have different properties, and this influences how long they persist in the soil. To achieve biochar with properties that provide higher persistence, it should be produced at higher temperatures for a sufficient duration. Measuring and calculating biochar persistence Established quantification methods of 100-year biochar persistence (e.g. referenced in IPCC inventory guidelines and used in voluntary carbon markets, to date) extrapolate short-term soil decomposition processes, and do not fully consider the processes that may explain millennial persistence. Calculations regarding biochar persistence have traditionally used a time span of 100 years to describe the amount of remaining carbon after a certain time. The use of specifically 100 years lacks a well founded scientific reason, but has been regarded as “far enough” into the future from a climate perspective and close enough for modelling to be meaningful. An active area of research relevant for the understanding biochar carbon storage durability is the development of advanced analytical characterisation methods of biochar that will enable measurement of the physicochemical heterogeneity in carbon structures present in biochar. Another area of continued research is biochar incubation, with a focus on field conditions, to elucidate both differences from laboratory conditions, and how transport processes affect biochar in the field. Recommendation and conclusion In the project, available research data has been aggregated into a functional model that calculates how much of the carbon in biochar remains after a given number of years. The model is based on the H/C ratio of the biochar placed in the soil and the annual average temperature at the location. The model is made freely accessible to provide biochar market actors with the best available knowledge for estimating the durability of biochar carbon. Existing research results provide a sufficient foundation for estimation of the amount of biochar expected to remain over time. Future research results are expected to lead to increased knowledge regarding the decomposition properties of biochar, in particular biochars with a very low H/C ratio. Therefore, this recommendation will be revised by the end of the project in 2025.

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