Relevant bibliographies by topics / Environmental pH

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Environmental pH'

Author: Grafiati
Published: 4 June 2021
Last updated: 20 February 2023

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Journal articles on the topic "Environmental pH"

1

KOBAYASHI, Hiroshi. "Bacterial Adaptation to Change in Environmental pH." Nippon Saikingaku Zasshi 51, no. 3 (1996): 745–53. http://dx.doi.org/10.3412/jsb.51.745.

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Gustafsson, T. K., and K. V. Waller. "Myths about pH and pH control." AIChE Journal 32, no. 2 (February 1986): 335–37. http://dx.doi.org/10.1002/aic.690320226.

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Tsai, Huei-Hsuan, and Wolfgang Schmidt. "The enigma of environmental pH sensing in plants." Nature Plants 7, no. 2 (February 2021): 106–15. http://dx.doi.org/10.1038/s41477-020-00831-8.

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Bila, T. A., E. V. Lyashenko, and O. V. Okhrimenko. "POTENTIOMETRIC METHOD OF NATURAL ENVIRONMENTAL WATERS PH DETERMINATION." Water bioresources and aquaculture, no. 1 (2021): 228–34. http://dx.doi.org/10.32851/wba.2021.1.17.

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Romanenko, Sergey, Timofey Radenkov, Egor Newsky, and Artur Kagirov. "Differential Sensor for PH Monitoring of Environmental Objects." MATEC Web of Conferences 79 (2016): 01008. http://dx.doi.org/10.1051/matecconf/20167901008.

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Barzaghi, C., T. W. K. Kok, S. F. Chew, J. M. Wilson, T. J. Lam, D. J. Randall, and Y. K. Ip. "Mudskippers detoxify ammonia externally by manipulating environmental pH." Comparative Biochemistry and Physiology Part B: Biochemistry and Molecular Biology 126 (July 2000): S9. http://dx.doi.org/10.1016/s0305-0491(00)80017-6.

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Arayici, Semiha, Resat Apak, and Vildan Apak. "Equilibrium modeling of ph in environmental treatment processes." Journal of Environmental Science and Health . Part A: Environmental Science and Engineering and Toxicology 31, no. 5 (May 1996): 1127–34. http://dx.doi.org/10.1080/10934529609376412.

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Esquivel-Upshaw, Josephine F., Shu-Min Hsu, Fan Ren, Jenna Stephany, Xinyi Xia, Chan-Wen Chiu, Dan Neal, and John J. Mecholsky. "Fracture of Lithia Disilicate Ceramics under Different Environmental Conditions." Materials 15, no. 15 (July 29, 2022): 5261. http://dx.doi.org/10.3390/ma15155261.

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The objective of this research was to quantify the effect of surface degradation and abrasion separately and in combination on the flexural strength of lithia disilicate ceramics. Lithia disilicate disks were fabricated using the lost wax technique and pressing in vacuum. The eight groups in this pilot experiment were (i) reference, hydrated in distilled water for 24 h prior to fracture; (ii) reference, non-hydrated group; (iii) 28-day pH cycling group; (iv) 125K chewing cycle group; (v) combined pH cycling + 125K chewing cycle; (vi) constant pH 2 solution for 28 days; (vii) constant pH 7 solution for 28 days; and (viii) constant pH 10 solution for 28 days. pH cycling is a method that alternates between pH 2, 7 and 10 over 28 days. A total of 15 disks were used for each group. All the groups were tested using the biaxial piston and a three-ball flexural strength test to obtain their biaxial flexural strength. pH 2 constant immersion demonstrated the highest fracture strength and was significantly greater than all other groups (p < 0.0001). Chewing and pH cycling + chewing groups exhibited the lowest fracture strengths and were significantly lower than all other groups (p < 0.0001). The damage observed from the chewing simulator does not represent apparent clinical fractures.
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Okano, Kunihiro, Kazuya Shimizu, Yukio Kawauchi, Hideaki Maseda, Motoo Utsumi, Zhenya Zhang, Brett A. Neilan, and Norio Sugiura. "Characteristics of a Microcystin-Degrading Bacterium under Alkaline Environmental Conditions." Journal of Toxicology 2009 (2009): 1–8. http://dx.doi.org/10.1155/2009/954291.

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The pH of the water associated with toxic blooms of cyanobacteria is typically in the alkaline range; however, previously only microcystin-degrading bacteria growing in neutral pH conditions have been isolated. Therefore, we sought to isolate and characterize an alkali-tolerant microcystin-degrading bacterium from a water bloom using microcystin-LR. Analysis of the 16S rRNA gene sequence revealed that the isolated bacterium belonged to the genusSphingopyxis, and the strain was named C-1.Sphingopyxissp. C-1 can grow; at pH 11.0; however, the optimum pH for growth was pH 7.0. The microcystin degradation activity of the bacterium was the greatest between pH 6.52 and pH 8.45 but was also detected at pH 10.0. ThemlrAhomolog encoding the microcystin-degrading enzyme in the C-1 strain was conserved. We concluded that alkali-tolerant microcystin-degrading bacterium played a key role in triggering the rapid degradation of microcystin, leading to the disappearance of toxic water blooms in aquatic environments.
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Yang, Wu, Guang Fu Li, Hao Guo, Jian Jiang Zhou, Chun Bo Huang, and Jiasheng Bai. "Effects of Environmental Factors on Stress Corrosion Cracking of Pipeline Steels." Key Engineering Materials 297-300 (November 2005): 939–44. http://dx.doi.org/10.4028/www.scientific.net/kem.297-300.939.

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Effects of some environmental factors on stress corrosion cracking (SCC) of pipeline steel X-70 both in near-neutral pH environments, including NS4 solution and several solutions containing main types of soil in the eastern part of China, and in high pH solution were studied by means of electrochemical measurement and slow strain rate testing (SSRT). The anodic polarization curves showed different features in near-neutral pH and high pH solutions in terms of active-passive transition behavior. In near-neutral pH solutions, the cracking mode was transgranular with the feature of quasi-cleavage, the susceptibility to SCC increased with decreasing potential, pH and temperature as well as increasing CO2, indicating a dominant mechanism of hydrogen induced cracking (HIC). In high pH solutions, the cracking behavior was similar to that in near-neutral pH solutions when the specimens were polarized at cathodic potentials, but quite different at anodic potentials. A comparison of the electrochemical behavior with the SCC potential region indicated a dominant SCC mechanism associated with anodic dissolution (AD) of X70 in high pH solution at anodic potentials. A preliminary experimental potential (E)-pH-SCC diagram has been established for X70 in near-neutral pH environments.
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Dissertations / Theses on the topic "Environmental pH"

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Hall, Rebecca. "Environmental pH adaptation in the nematode Caenorhabditis elegans." Thesis, University of Kent, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.497538.

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Microorganisms are constantly adapting to changes within their environment. The soil dwelling nematode Caenorhabditis elegans encounters a multitude of environmental conditions during its lifetime including hypoxia, UV exposure, temperature fluctuations and starvation. However, living in a soil environment C. elegans will also encounter fluctuations in environmental pH, a condition to which the adaptive response has not been characterised. The aim of this study was to analyse the global transcriptional response to both acid and alkaline conditions, to identify how the nematode adapts to these environments. Caenorhabditis elegans were resistant to pH conditions between pH3-10 over a four-hour period and the environmental pH influenced the expression of genes whose products are involved in cell signalling, metabolism, cuticle biosynthesis and ion/nutrient transport. The majority of genes that were differentially regulated in acid and alkaline environments encoded uncharacterised proteins and represented 33 and 39% of the genes. Post-transcriptional gene silencing of targets did not confer pH sensitivity, which was attributed to remaining transcripts. As a result of alternative splicing, the gene RO1E6.3 encodes two alpha carbonic anhydrases named, CAH-4a and CAH-4b. Biochemical analysis confirmed that CAH-4b, which showed up regulation at the transcriptional level in alkaline conditions (5-fold), was also the most active CA isoform. Crystallisation studies are being performed on CAH-4b to aid in the identification of the protein's biological function.
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Romppanen, T. (Tatu). "Valuma-aluetekijöiden vaikutus virtavesien pH- ja lämpötila-arvoihin." Master's thesis, University of Oulu, 2016. http://urn.fi/URN:NBN:fi:oulu-201604081410.

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Pohjoisen vesistöissä happamuus tuottaa usein ongelmia vesien ekologiselle tilalle ja virkistyskäytölle. Kausittaista happamuutta esiintyy yleensä alueilla, joilla sijaitsee turvepitoisia happamia sulfaattimaita. Tässä työssä pyritään löytämään uusien paikkatietoihin perustuvien menetelmien avulla happamuuden lähteitä ja keinoja happamuuspiikkien ennakoimiseksi. Pohjois-pohjanmaalla Oulun lähistöllä sijaitseva Sanginjoki on yksi kausittaisesta happamuudesta kärsivistä vesistöistä. Sanginjoen happamuuden lähteitä ja arvoja on tutkittu Suomen ympäristökeskuksen Kaupunki ja vesi — Sanginjoen virkistyskäyttöarvon parantaminen ja ekologinen kunnostus -hankkeessa, jonka koko valuma-alueen kattavaan ja jatkuvatoimiseen pH-mittausaineistoon tämä työ pohjautuu. Työssä verrataan Sanginjoen valuma-alueelta saatuja veden minimi pH-arvoja kunkin pH-mittauspisteen muodostaman alivaluma-alueen paikkatietoihin/valuma-aluetekijöihin. Sanginjoen alueen valuma-aluetekijätiedot saatiin CSN:n PaITuli ja GTK:n Hakku -paikkatietojen latauspalveluista. Paikkatietojen käsittely ja mittapisteiden alivaluma-alueiden muodostaminen työssä tehtiin ArcGIS:n karttapohja ArcMap:lla. Työn tuloksissa löytyi yhteys happamien sulfaattimaiden, suoalueiden ja eräiden maaperäluokkien happamuutta vahvistavasta vaikutuksesta. Lisäksi eräät maaperäluokat ja laajemmat vesistöalueet työn tulosten perusteella vähentävät happamuutta virtavesissä. Tulosten pohjalta luotiin happamuutta kuvaava usean muuttujan regressiomalli, jonka avulla voidaan ennustaa lähes puolet (42,3 %) veden minimi pH-arvon suuruudesta. Tulokset antavat tukea jo aiemmin tunnetuille toimenpiteille happaman kuormituksen synnyn ehkäisemiseksi. Tietoja tulisi hyödyntää maankäytön suunnittelussa erityisesti Suomen rannikkoseutujen sulfaattimaavyöhykkeellä
Acidification of water courses is a serious problem to the ecological status and the recreational use of lakes and rivers. Seasonal acidity is a common phenomenon in the northern areas which consists of peatlands and sulphate soils. This thesis includes new geographical information system (GIS) based methods to identify the sources of acidity and ways to predict the acidification peaks of streams. River Sanginjoki at Northern Ostrobothnia, Finland is one of the river systems where periodic acidity occurs frequently. The sources and rates of acidity in the River Sanginjoki have been studied in previous projects. This thesis is utilize previous databases and is based on the whole river basin. The relations between the minimum pH-values of each measurement and the properties of their sub-catchments were studied in this thesis. The data of the catchment properties were downloaded from Finnish GIS databases PaITuli and Hakku. The processing of the catchment data and the formation of the sub-catchment areas were performed using the ArcGIS software package. The results showed acidity increasing effects with presence of the sulphate and four other soil types, and peatlands in the catchment area. Also evidence of decreasing acidity with certain soils types and water areas were found. A multiple regression model, which can be used to predict a sample’s minimum pH-value. The regression model can determine almost half (42.3%) of the variation of the minimum pH-value. The results of this thesis support the known methods of preventing the formation of acid loads. Further on they can be suitable for planning the land use, especially in the coastal areas of Finland sulphate soils are common
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Tibbits, Matthew A. Budd Ann F. "The effects of decling environmental pH on coral microstructure and morphology." [Iowa City, Iowa] : University of Iowa, 2009. http://ir.uiowa.edu/etd/445.

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Tibbits, Matthew A. "The effects of decling environmental pH on coral microstructure and morphology." Thesis, University of Iowa, 2009. https://ir.uiowa.edu/etd/445.

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Coral reefs are faced and will be faced with many challenges this century. One danger is the rapid decline of oceanic pH due to anthropogenic sources. The more acidic the environment becomes, the harder reefs and coral (order: scleractinia) in particular will be hit. Experiments to measure the effect on scleractinian coral were performed to glean a better understanding of the processes that will be affected by our acidifying oceans. Additionally, the search for and analysis of coral microstructure and micromorpholgy were carried out in an attempt to understand homology within an environmentally responsive taxa.
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Martin, Christopher S. "Controlled Release of Alkalinity Using pH-Responsive Polymer Carriers." Thesis, Tufts University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10165326.

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Low groundwater pH is frequently cited as inhibiting the performance of in-situ bioremediation of chlorinated solvents at contaminated sites. A common method of pH control is injection of solutions containing alkalinity, but alternatives for prolonged, passive pH control are needed. This work explores pH-responsive hydrogel coatings on MgO nanoparticles as vehicles for controlled release of alkalinity. Chitosan cross-linked with glutaraldehyde was evaluated as a representative hydrogel coating. The effects of coating thickness and cross-linking on the rate of alkalinity release were experimentally evaluated using batch dissolution experiments. Dissolution rates were found to be up to an order of magnitude slower for coated particles than for uncoated particles. A diffusion model was developed for the dissolution rate of coated particles, and the model was able to account for the dissolution rate as a function of coating thickness over a range of pH.

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Rankin, Ashley. "The Effects of Reduced pH on Decorator Crab Morphology, Physiology and Behavior." Thesis, University of California, San Diego, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10634897.

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Crabs in the family Majoidae camouflage by decorating their exoskeletons with organisms and debris from their environment. This form of camouflage, involving both the act of decorating and carrying of these decorations, is thought to be energetically costly, and may present a trade-off under stressful environmental conditions. The energetic cost of decoration behavior has been evinced by reduced organic content due to elevated metabolism. In the context of previous research demonstrating that many marine calcifiers experience metabolic costs under experimental ocean acidification conditions, we hypothesized that decorator crabs exposed to reduced pH will have insufficient energy to support regulatory processes along with decoration behavior. Thus, we predicted that energy will be allocated towards growth and calcification at the expense of decoration behavior. Dwarf teardrop crabs, Pelia tumida, were exposed to ambient (pH = 8.0, pCO2 = 613 µatm) and reduced (pH = 7.75, pCO2 = 894 µatm) pH conditions for five weeks. Half of the animals in each treatment were given two sponge species, Halichondria panacea and Haliclona permollis, to decorate with, whereas the remaining animals were not allowed to decorate. At the end of the experiment, all animals were analyzed for exoskeleton mineral content (Ca and Mg) using EDX and ICP-MS, organic content (a proxy for metabolism) using TGA, and decoration behavior by quantifying sponge mass and percent cover. Overall, decorator crabs showed no signs of energy limitation under reduced pH conditions. Neither growth, exoskeleton mineral content, nor organic content of crabs differed among pH or decoration treatments. In addition, both sponge mass and percent cover remained the same across pH treatments, indicating no effect of reduced pH on decoration behavior, and thus the ability to camouflage. The maintenance of physiological processes without metabolic costs in P. tumida exposed to reduced pH radiates from the emerging trends on the susceptibility of crustaceans to changes in ocean chemistry associated with ocean acidification.

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Len, Alice Chen Liang. "Effect Of Environmental Ph On The Proteome Of The Dental Pathogen Streptococcus Mutans." Thesis, The University of Sydney, 2005. http://hdl.handle.net/2123/4968.

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Gundersen, Jennifer Lisa. "Acid dissociation of chloroguaiacols and pH dependent sorption to estuarine sediments." W&M ScholarWorks, 1995. https://scholarworks.wm.edu/etd/1539616676.

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Chloroguaiacols are common components of bleached kraft pulp mill effluent known to bioaccumulate in aquatic organisms, and sorb onto particulate material and sediments. Ionization properties of the chloroguaiacols must be known in order to explain their sorptive behavior in aquatic systems. to obtain this information, thermodynamic acid dissociation constants (p&K\sb{lcub}\rm a{rcub})& of guaiacol (o-methoxyphenol) and nine chloroguaiacols have been determined by spectrophotometric methods. These experimental p&K\sb{lcub}\rm a{rcub}& values have been compared with literature values, values predicted by the Hammett equation and predictions by quantum chemical calculations using MOPAC 6.0 with AM1 and MNDO Hamiltonian operators. Experimental and predicted acidities were linearly related, and the correlation and regression equations obtained have been used to calculate p&K\sb{lcub}\rm a{rcub}& values for those chloroguaiacols that were unavailable for experimental measurement. Sorption of chloroguaiacols onto sediments may result in reduced bioavailabilty to aquatic species, increased degradation rates or rapid burial. Conversely, it may result in increased exposure to deposit feeding species with subsequent transfer to higher trophic levels. The sorption of four chloroguaiacols (5-chloroguaiacol, 4,6-dichloroguaiacol, 4,5,6-trichloroguaiacol and tetrachloroguaiacol) with p&K\sb{lcub}\rm a{rcub}& values ranging from 9.06 to 6.06 was investigated on four estuarine sediments. The effect on sorption of aqueous phase pH, sediment organic carbon content and degree humification was investigated. Sorption coefficients, &K\sb{lcub}\rm d{rcub}&, were determined at two pH values (6.6 and 7.8). Linear relationships were observed between &K\sb{lcub}\rm d{rcub}& and both % total organic carbon(TOC) and % humic acids at each pH. &K\sb{lcub}\rm oc{rcub}& and &K\sb{lcub}humic{rcub},& sorption coefficients normalized to % TOC and % humic acids, were calculated. In addition to the amount of TOC present, the type of organic matter (ie. humic acids) is an important factor in sorption. Aqueous phase pH governs the ionization of chloroguaiacols. Sorption of the ionized and molecular species are different due, in part, to the different solubilities of the species and was reflected in the different &K\sb{lcub}\rm d{rcub}& values determined at each pH.
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Elzahabi, Malak. "The effect of soil pH on heavy metal transport in the vadose zone /." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36804.

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This research study provides the experimental information necessary for numerical analyses, structured to account for vadose zone transport of heavy metals. Particular attention is payed to the effect of degree of saturation, the presence of carbonate, soil pH and heavy metals concentrations. In addition, attention is directed to an evaluation of the coupled solute-water transport mechanisms. A method that fully describes the coupling effects on the transport coefficient based on experimental evidence provides successful predictions of the rate of transport of the heavy metals through the unsaturated soil in a pH-controlled environment.
In the experimental part of this research, one dimensional solute and moisture flow (leaching) tests, using different heavy metal permeants, were conducted on an unsaturated illitic soil at varying pH values. Experimental results showed that the retention and migration of heavy metals are highly dependent on the soil pH, the presence of carbonates, the degree of saturation, the influent concentration and the time duration. At high soil pH and carbonate content, heavy metals were retained in the soils if the buffering capacity was high enough to resist the acidic input solution, and sorption processes will prevail in the carbonate phase. As the soil pH decreases, the dissolution of carbonates increases and cation exchange capacity becomes the more dominant process in heavy metals retention.
The numerical study developed a model to analyse and predict the transport of the contaminant in unsaturated clayey soils in which some of the species were adsorbed on clay particles surfaces. The proposed mathematical model was based on the postulates of irreversible thermodynamics and is also applicable in a one-dimensional case. In this model, various solute transport mechanisms such as diffusion and sorption were considered. Results indicated that the diffusion coefficient is necessary to provide a good agreement between the experimentally measured and the theoretically predicted values of contaminant transport through the soil. The numerical results of the coupled solute and moisture equations showed that the transport coefficients strongly and accurately depend on solute and volumetric content. (Abstract shortened by UMI.)
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Al, Minshid Alaa Hani Naser. "Surface chemistry of metal oxide nanoparticles in biological and environmental media of varying pH." Diss., University of Iowa, 2018. https://ir.uiowa.edu/etd/6359.

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Investigate the interaction of nanomaterials with biological systems, known as nano-bio interaction is of great interest for the assessment of the concern arising from nanomaterials progressive use. Such interaction determines nanomaterials potential effect on human and environment becomes more and more important to understand how they interact with living organisms and the environment. The novel physicochemical characteristics of nanomaterials, such as their small size, large surface area to volume ratio and surface energy, may initiate new toxicological effects due to nanomaterials ability to enter into the biological systems through adsorption and dissolution and modify the structure of various macromolecules An example of these interactions is the adsorption of proteins on nanoparticles surface forming what is known as the 'protein corona'. Therefore, being able to understand how these molecules and other biologically important species are adsorbed and interact, should help us to reduce any adverse impacts of nanoparticles on human health and the environment. Due to the importance of surface composition and surface functionality in nanotoxicology, analytical tools that can probe the change in the structure and composition of the nanoparticles in aqueous media are crucial but remain limited. Therefore in this work, in situ characterization of the liquid–solid interface to probe surface adsorption of environmentally and biologically relevant media on nanoparticle surfaces has been conducted. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy provides the molecular information that allows for the determination of the adsorption mode such as conformational and structural changes of the coordinating ligand. Surface adsorption of titanium dioxide (TiO2) nanoparticles have been investigated in different biological media typically used for toxicity studies and show that the surface composition of TiO2 nanoparticles depends to a large extent on the composition of the medium due to surface adsorption. Moreover, hydrodynamic diameter and surface charge of TiO2 NPs were evaluated using dynamic light scattering DLS. The results indicated that TiO2 NPs undergo different trends in aggregation upon the adsorption of biological media on its surface and zeta potential measurements showed surface charge alterations which are consistent with the aggregation study. In order to understand the dynamic transformations of nanomaterials in biological environments, the effect of dissolution has been predicted. Copper oxide CuO and zinc oxide ZnO nanoparticles were used to study dissolution due to their instability in biological media. Once these particles exposed to solutions they release their ions and tend to aggregate. Therefore, the dissolution of these materials was conducted at size ca. 24 nm and nanoparticles coated with proteins and humic acid employing simulated lung fluids as models to develop a better understanding of how these properties effect the solubility and stability in biological systems. From this study, it was found that both copper oxide and zinc oxide NPs showed different trends in dissolution. Cu and Zn ions once coated with proteins and HA highly dissolved in ALF at low pH 4.5 compared with other fluids (Gamble’s solution and water) at extracellular pH which shows only slightly enhanced in the basal condition. The acidity of ALF may explain the higher solubility of metals that are phagocytized versus those that remain extracellular. Some general conclusions can be drawn from these investigations. It seems that analytical tools to characterize the interfacial region between nanopaerticles and these complex systems provide a reasonably good qualitative and quantitative description of the interactions.
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Books on the topic "Environmental pH"

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Moore, Ralph L. Environmental protection by the neutralization of wastewater using pH control. Research Triangle Park, N.C., U.S.A: Instrument Society of America, 1995.

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Price, Cynthia B. Transformation of RDX and HMX under controlled Eh/pH conditions. Vicksburg, Miss: U.S. Army Engineer Waterways Experiment Station, 1998.

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Paur, Richard J. Development and evaluation of a real-time pH and conductivity rain monitor. Research Triangle Park, NC: U.S. Environmental Protection Agency, Environmental Monitoring Systems Laboratory, 1987.

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Lytle, Darren A. Stagnation time, composition, pH, and orthophosphate effects on metal leaching from brass. Cincinnati, Ohio: National Risk Management Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, 1996.

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Swanson, Trevor. Walla Walla River Basin fecal coliform bacteria and pH total maximum daily load study, data summary report. Olympia, WA: Washington State Dept. of Ecology, 2005.

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Swanson, Trevor. Walla Walla River Basin fecal coliform bacteria and pH total maximum daily load study, data summary report. Olympia, WA: Washington State Dept. of Ecology, 2005.

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Fisher, Lawrence H. Effect of water-column pH on sediment-phosphorus release rates in Upper Klamath Lake, Oregon, 2001. Portland, Or: U.S. Dept. of the Interior, U.S. Geological Survey, 2004.

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Fisher, Lawrence H. Effect of water-column pH on sediment-phosphorus release rates in Upper Klamath Lake, Oregon, 2001. Portland, Or: U.S. Dept. of the Interior, U.S. Geological Survey, 2004.

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Fiske, Steven. Macroinvertebrate survey of 25 soft water-pH sensitive lakes in Vermont. [Waterbury, Vt.?]: Special Studies & Surveillance Unit, Dept. of Environmental Conservation, 1987.

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Schroder, L. J. Precision of the measurement of pH and specific conductance at National Atmospheric Deposition Program monitoring sites, October 1981 - November 1983. Lakewood, Colo: U.S. Dept. of the Interior, Geological Survey ; Denver, CO, 1985.

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Book chapters on the topic "Environmental pH"

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Willey, Neil. "Soil pH." In Environmental Plant Physiology, 227–52. New York, NY : Garland Science, 2016.: Garland Science, 2018. http://dx.doi.org/10.1201/9781317206231-10.

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Patnaik, Pradyot. "pH and Eh." In Handbook of Environmental Analysis, 273–76. Third edition. | Boca Raton : Taylor & Francis, CRC Press, 2017.: CRC Press, 2017. http://dx.doi.org/10.1201/9781315151946-48.

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Latif, Usman, and Franz L. Dickert. "pH Measurements." In Environmental Analysis by Electrochemical Sensors and Biosensors, 751–77. New York, NY: Springer New York, 2014. http://dx.doi.org/10.1007/978-1-4939-1301-5_4.

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Gray, James R. "pH Analyzers and Their Application." In Environmental Instrumentation and Analysis Handbook, 459–90. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2005. http://dx.doi.org/10.1002/0471473332.ch22.

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Ibanez, Jorge G., Margarita Hernandez-Esparza, Carmen Doria-Serrano, Arturo Fregoso-Infante, and Mono Mohan Singh. "Experimental Transitions in E vs pH (or Pourbaix) Diagrams." In Environmental Chemistry, 79–88. New York, NY: Springer New York, 2008. http://dx.doi.org/10.1007/978-0-387-49493-7_6.

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Lang, Mark. "Use of Instrumentation for pH Control." In Environmental Instrumentation and Analysis Handbook, 731–39. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2005. http://dx.doi.org/10.1002/0471473332.ch33.

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Loconto, Paul R. "An Introduction to pH Measurement." In Laboratory Experiments in Trace Environmental Quantitative Analysis, 9–16. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003260707-2.

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Noble, Taryn L., Bernd Lottermoser, and Anita Parbhakar-Fox. "pH Testing Methods for Sulfidic Mine Wastes." In Environmental Indicators in Metal Mining, 199–210. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-42731-7_11.

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Behera, Anindita, and Santwana Padhi. "pH-Sensitive Polymeric Nanoparticles for Cancer Treatment." In Environmental Chemistry for a Sustainable World, 401–25. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-14848-4_15.

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Noble, Taryn L., and Bernd Lottermoser. "Modified Abrasion pH and NAGpH Testing of Minerals." In Environmental Indicators in Metal Mining, 211–20. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-42731-7_12.

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Conference papers on the topic "Environmental pH"

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Stoyanov, Plamen G., Michael F. Shaw, Craig A. Grimes, Stephen A. Doherty, and W. R. Seitz. "A Remotely Queried Magnetism-Based pH Sensor." In International Conference On Environmental Systems. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1998. http://dx.doi.org/10.4271/981763.

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Ilavský, Ján, Danka Barloková, and Ondrej Kapusta. "Removal of Humic Substances in Water by Granular Activated Carbon." In Environmental Engineering. VGTU Technika, 2017. http://dx.doi.org/10.3846/enviro.2017.078.

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The basic characteristics of humic substances and their negative influence on water quality and its treatment are described. The paper presents the results of removing humic substances from water from the Hriňová (Slovakia) water reservoir with the addition of humic substances using granular activated carbon (GAC) from two producers (Chemviron, Cabot) at three different pH levels of water. The results of static experiments involving the removal efficiency of humic substances using TOC parameters and the instantaneous water adsorption capacity, which uses materials at the contact time of the water with GAC material, was calculated. The results show that the pH of the water had no significant effect on the change in the efficiency of removing humic substances from water. A high level of efficiency (50%) and the lowest value of TOC are obtained at a pH of 6.5. The GAC adsorption capacity of humic substances, depending on the contact time with the water, ranged from 0.17 mg/g for one hour to 0.56 mg/g for eight hours of contact time. The most effective material was Filtrasorb F400.
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Plaschke, Markus, Michael Geyer, Johannes Reichert, and Hans-Joachim Ache. "Submicron fiber optic sensors for calcium ions and pH with internal calibration." In Environmental Sensing III, edited by Robert A. Lieberman. SPIE, 1997. http://dx.doi.org/10.1117/12.276178.

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Liu, Huqun, William R. Seitz, Craig A. Grimes, Keat Ghee Ong, and P. G. Stoyanov. "Remotely queried magnetoacoustic sensors for monitoring starch concentrations, pH, and polymer curing." In Environmental and Industrial Sensing, edited by Tuan Vo-Dinh and Stephanus Buettgenbach. SPIE, 2001. http://dx.doi.org/10.1117/12.417444.

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Ormsbee, Lindell. "A Methodology for pH TMDLs: Application to Kentucky Watersheds." In World Water and Environmental Resources Congress 2001. Reston, VA: American Society of Civil Engineers, 2001. http://dx.doi.org/10.1061/40569(2001)189.

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Whitaker, Dawn R., Kevin L. Staton, James E. Alleman, and John W. Lane. "Loading Balance and Influent pH in a Solids Thermophilic Aerobic Reactor." In International Conference On Environmental Systems. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2005. http://dx.doi.org/10.4271/2005-01-2982.

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Butler, Thomas M., Brian D. MacCraith, and Colette M. McDonagh. "Development of an extended-range fiber optic pH sensor using evanescent wave absorption of sol-gel-entrapped pH indicators." In European Symposium on Optics for Environmental and Public Safety, edited by Annamaria V. Scheggi. SPIE, 1995. http://dx.doi.org/10.1117/12.221730.

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Khancheuski, M. А., V. N. Lesik, and E. I. Kvasyuk. "SYNTHESIS OF 8-BROMOADENOSINE AT DIFFERENT PH VALUES." In SAKHAROV READINGS 2021: ENVIRONMENTAL PROBLEMS OF THE XXI CENTURY. International Sakharov Environmental Institute of Belarusian State University, 2021. http://dx.doi.org/10.46646/sakh-2021-2-132-135.

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This article shows methods for the preparation of 8-bromoadenosine which is an important intermediate in the syntheses of analogs of purines nucleosides and nucleotides with a broad spectrum of biological activity. The influence of the pH values of the medium on the yield of 8-bromoadenosine was studied. It was showed that pH 4.3 is optimal for the preparation of 8-bromoadenosine by reaction of adenosine with a solution of bromine in water.
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Singovszka, Eva, and Magdalena Balintova. "FTIR Spectra Analysis of Sediment Influenced by Acid Mine Drainage." In Environmental Engineering. VGTU Technika, 2017. http://dx.doi.org/10.3846/enviro.2017.003.

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The contamination of aquatic and terrestrial ecosystems with heavy metals and other mining chemicals have been major environmental problems in many mining areas of the world. Industrial wastes, geochemical structure and metals mining form a potential source of metal contaminants in the aquatic environment especially in sediment. In Slovak Republic there are some localities with existing acid mine drainage (AMD) generation conditions. The most critical values were observed in the abandoned deposit Smolnik. Waters from the earth surface penetrated the mine and they are enriched with metals and their pH values decreased. Increasing of pH after their mixing with surface water has negative influence on accumulation of pollutants in sediment. The aim of this paper is to investigate the use of Fourier transform infrared (FTIR) transmittance spectroscopy for identification of changes of functions group in the sediment composition influenced by acid mine drainage. Chemical parameters of sediment quality were studied also by X-ray fluorescence spectrometry (XRF).
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Xiao, Ming, Ashleigh D. Love, and Zheng Teng. "pH Variation and Its Effect on Metal Concentration during Electrokinetics." In World Environmental and Water Resources Congress 2009. Reston, VA: American Society of Civil Engineers, 2009. http://dx.doi.org/10.1061/41036(342)262.

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Reports on the topic "Environmental pH"

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Prusky, Dov, and Jeffrey Rollins. Modulation of pathogenicity of postharvest pathogens by environmental pH. United States Department of Agriculture, December 2006. http://dx.doi.org/10.32747/2006.7587237.bard.

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Until recently, environmental pH was not considered a factor in determining pathogen compatibility. Our hypothesis was that the environmental pH at the infection site, which is dynamically controlled by activities of both the host and the pathogen, regulates the expression of genes necessary for disease development in Colletotrichum gloeosporioides and Sclerotinia sclerotiorum. This form of regulation ensures that genes are expressed at optimal conditions for their encoded activities.Pectate lyase encoded by pelB, has been demonstrated to play a key role in virulence of C. gloeosporioides in avocado fruit. Polyglacturonase synergism with oxalic acid production is considered to be an essential pathogenicity determinant in the interactions of S. sclerotiorum with its numerous hosts. A common regulatory feature of these virulence and pathogenicity factors is their dependence upon environmental pH conditions within the host niche to create optimal conditions for expression and secretion. In this proposal we have examined, 1) the mechanisms employed by these fungi to establish a suitable pH environment, 2) the molecular levels at which genes and gene products are regulated in response to environmental pH, and 3) the molecular basis and functional importance of pH-responsive gene regulation during pathogenicity. The specific objectives of the proposal were: 1. Characterize the mechanism of local pH modulation and the effect of ambient pH on the expression and secretion of virulence factors. 2. Provide evidence that a conserved molecular pathway for pH-responsive gene expression exists in C. gloeosporioides by cloning a pacC gene homologue. 3. Determine the role of pacC in pathogenicity by gene disruption and activating mutations. Major conclusions 1. We determined the importance of nitrogen source and external pH in the secretion of the virulence factor pectate lyase with respect to the ambient pH transcriptional regulator pacC. It was concluded that nitrogen source availability and ambient pH are two independent signals for the transcriptional regulation of genes required for the disease process of C. gloeosporioides and possibly of other pathogens. 2. We also determined that availability of ammonia regulate independently the alkalinization process and pelB expression, pecate lyase secretion and virulence of C. gloeosporioides. 3. Gene disruption of pacC reduced virulence of C. gloeosporioides however did not reduced fully pelB expression. It was concluded that pelB expression is regulated by several factors including pH, nitrogen and carbon sources. 4. Gene disruption of pacC reduced virulence of S. slcerotiourum Creation of a dominant activating
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Janardhanam, Vijay, and Scott Carlton James. Sandia National Laboratories environmental fluid dynamics code : pH effects user manual. Office of Scientific and Technical Information (OSTI), February 2012. http://dx.doi.org/10.2172/1039008.

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Ji, Yi, Bob McCullouch, and Zhi Zhou. Evaluation of Anti-Icing/De-Icing Products Under Controlled Environmental Conditions. Purdue University, 2020. http://dx.doi.org/10.5703/1288284317253.

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Snow and ice removal are important tasks during the winter season and large amounts of anti-icing and de-icing chemicals are used and there is a critical need to review and synthesize information from the literature to compare and contrast anti-icing and de-icing chemicals to understand their environmental impact and support decision making. The effectiveness, costs, and environmental impact of commonly used and alternative anti-icing and de-icing chemicals were reviewed in this study. Application of anti-icing and de-icing chemicals may increase ion concentrations in soils and change nitrogen cycle, soil pH, and trace metal concentrations, affect surface water and groundwater, and increase public health risks. Life cycle assessment was conducted to quantitively evaluate environmental impact of selected anti-icing and de-icing chemicals. A decision support tool on environmental impact was developed to evaluate environmental impact of anti-icing and de-icing chemicals in ten different environmental impact categories. The results showed the environmental life cycle assessment tool developed in this study can be used to compare multiple environment impacts to support decision making for winter operation chemicals.
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Livingston, R. R., L. Baylor, and G. G. Wicks. Development of novel Sol-Gel Indicators (SGI's) for in-situ environmental measurements: Part 1, Program and a new pH Sol-Gel Indicator. Office of Scientific and Technical Information (OSTI), November 1992. http://dx.doi.org/10.2172/6636793.

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Livingston, R. R., L. Baylor, and G. G. Wicks. Development of novel Sol-Gel Indicators (SGI`s) for in-situ environmental measurements: Part 1, Program and a new pH Sol-Gel Indicator. Office of Scientific and Technical Information (OSTI), November 1992. http://dx.doi.org/10.2172/10143056.

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Moores, Lee, Stacy Jones, Garrett George, David Henderson, and Timothy Schutt. Photo degradation kinetics of insensitive munitions constituents nitroguanidine, nitrotriazolone, and dinitroanisole in natural waters. Engineer Research and Development Center (U.S.), September 2021. http://dx.doi.org/10.21079/11681/41900.

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Herein the matrix effects on the kinetics of aqueous photolysis for the individual munitions constituents of IMX-101: nitroguanidine (NQ), dinitroanisole (DNAN), and nitrotriazolone (NTO) are reported along with the environmentally relevant kinetics and quantum yields. Photolysis potentially represents a major degradation pathway for these munitions in the environment and further understanding the complex matrices effects on photolytic kinetics was needed. Aqueous systems are of particular interest due to the high solubility of NQ (3,800 ppm) and NTO (16,642 ppm) compared to the traditional munitions trinitrotoluene (TNT, 100.5 ppm) and 1,3,5-trinitro-1,3,5-triazine (RDX, 59.9 ppm). Environmental half-lives (and quantum yields) were found to be 0.44 days, 0.83 days, and 4.4 days for NQ, DNAN, and NTO, respectively, under natural sunlight. In laboratory experiments using nominally 300 nm bulbs in a merry-go-round style reactor in DI water the relative rate of photolysis for the three munitions constituents followed the same order NQ > DNAN > NTO, where DNAN and NTO reacted 57 and 115 times more slowly, respectively, than NQ. In the various environmentally relevant matrices tested in the laboratory experiments NQ was not significantly affected, DNAN showed a faster degradation with increasing ionic strength, and NTO showed a modest salinity and pH dependence on its rate of photolysis.
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Ron, Eliora, and Eugene Eugene Nester. Global functional genomics of plant cell transformation by agrobacterium. United States Department of Agriculture, March 2009. http://dx.doi.org/10.32747/2009.7695860.bard.

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The aim of this study was to carry out a global functional genomics analysis of plant cell transformation by Agrobacterium in order to define and characterize the physiology of Agrobacterium in the acidic environment of a wounded plant. We planed to study the proteome and transcriptome of Agrobacterium in response to a change in pH, from 7.2 to 5.5 and identify genes and circuits directly involved in this change. Bacteria-plant interactions involve a large number of global regulatory systems, which are essential for protection against new stressful conditions. The interaction of bacteria with their hosts has been previously studied by genetic-physiological methods. We wanted to make use of the new capabilities to study these interactions on a global scale, using transcription analysis (transcriptomics, microarrays) and proteomics (2D gel electrophoresis and mass spectrometry). The results provided extensive data on the functional genomics under conditions that partially mimic plant infection and – in addition - revealed some surprising and significant data. Thus, we identified the genes whose expression is modulated when Agrobacterium is grown under the acidic conditions found in the rhizosphere (pH 5.5), an essential environmental factor in Agrobacterium – plant interactions essential for induction of the virulence program by plant signal molecules. Among the 45 genes whose expression was significantly elevated, of special interest is the two-component chromosomally encoded system, ChvG/I which is involved in regulating acid inducible genes. A second exciting system under acid and ChvG/Icontrol is a secretion system for proteins, T6SS, encoded by 14 genes which appears to be important for Rhizobium leguminosarum nodule formation and nitrogen fixation and for virulence of Agrobacterium. The proteome analysis revealed that gamma aminobutyric acid (GABA), a metabolite secreted by wounded plants, induces the synthesis of an Agrobacterium lactonase which degrades the quorum sensing signal, N-acyl homoserine lactone (AHL), resulting in attenuation of virulence. In addition, through a transcriptomic analysis of Agrobacterium growing at the pH of the rhizosphere (pH=5.5), we demonstrated that salicylic acid (SA) a well-studied plant signal molecule important in plant defense, attenuates Agrobacterium virulence in two distinct ways - by down regulating the synthesis of the virulence (vir) genes required for the processing and transfer of the T-DNA and by inducing the same lactonase, which in turn degrades the AHL. Thus, GABA and SA with different molecular structures, induce the expression of these same genes. The identification of genes whose expression is modulated by conditions that mimic plant infection, as well as the identification of regulatory molecules that help control the early stages of infection, advance our understanding of this complex bacterial-plant interaction and has immediate potential applications to modify it. We expect that the data generated by our research will be used to develop novel strategies for the control of crown gall disease. Moreover, these results will also provide the basis for future biotechnological approaches that will use genetic manipulations to improve bacterial-plant interactions, leading to more efficient DNA transfer to recalcitrant plants and robust symbiosis. These advances will, in turn, contribute to plant protection by introducing genes for resistance against other bacteria, pests and environmental stress.
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Prusky, Dov, Nancy P. Keller, and Amir Sherman. global regulation of mycotoxin accumulation during pathogenicity of Penicillium expansum in postharvest fruits. United States Department of Agriculture, January 2014. http://dx.doi.org/10.32747/2014.7600012.bard.

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Background to the topic- Penicilliumas a postharvest pathogen and producer of the mycotoxin PAT. Penicilliumspp. are destructive phytopathogens, capable of causing decay in many deciduous fruits, during postharvest handling and storage; and the resulting losses can amount to 10% of the stored produce and the accumulation of large amounts of the mycotoxinpatulin. The overall goal of this proposal is to identify critical host and pathogen factors that modulate P. expansummycotoxin genes and pathways which are required for PAT production and virulence. Our preliminary results indicated that gluconic acid are strongly affecting patulin accumulation during colonization. P. expansumacidifies apple fruit tissue during colonization in part through secretion of gluconic acid (GLA). Several publications suggested that GLA accumulation is an essential factor in P. expansumpathogenicity. Furthermore, down regulation of GOX2 significantly reduced PAT accumulation and pathogenicity. PAT is a polyketide and its biosynthesis pathway includes a 15-gene cluster. LaeA is a global regulator of mycotoxin synthesis. It is now known that patulin synthesis might be subjected to LaeA and sometimes by environmental sensing global regulatory factors including the carbon catabolite repressor CreA as well as the pH regulator factor PacC and nitrogen regulator AreA. The mechanisms by which LaeA regulates patulin synthesis was not fully known and was part of our work. Furthermore, the regulatory system that controls gene expression in accordance with ambient pH was also included in our work. PacC protein is in an inactive conformation and is unable to bind to the promoter sites of the target genes; however, under alkaline growth conditions activated PacC acts as both an activator of alkaline-expressed genes and a repressor of acid-expressed genes. The aims of the project- This project aims to provide new insights on the roles of LaeA and PacC and their signaling pathways that lead to GLA and PAT biosynthesis and pathogenicity on the host. Specifically, our specific aims were: i) To elucidate the mechanism of pH-controlled regulation of GLA and PAT, and their contribution to pathogenesis of P. expansum. We are interested to understanding how pH and/or GLA impact/s under PacC regulation affect PAT production and pathogenesis. ii) To characterize the role of LaeA, the global regulator of mycotoxin production, and its effect on PAT and PacC activity. iii) To identify the signaling pathways leading to GLA and PAT synthesis. Using state- of-the-art RNAseq technologies, we will interrogate the transcriptomes of laeAand pacCmutants, to identify the common signaling pathways regulating synthesis of both GLA and PAT. Major conclusions, solutions, achievements- In our first Aim our results demonstrated that ammonia secreted at the leading edge of the fungal colony induced transcript activation of the global pH modulator PacC and PAT accumulation in the presence of GLA. We assessed these parameters by: (i) direct exogenous treatment of P. expansumgrowing on solid medium; (ii) direct exogenous treatment on colonized apple tissue; (iii) growth under self-ammonia production conditions with limited carbon; and (iv) analysis of the transcriptional response to ammonia of the PAT biosynthesis cluster. Ammonia induced PAT accumulation concurrently with the transcript activation of pacCand PAT biosynthesis cluster genes, indicating the regulatory effect of ammonia on pacCtranscript expression under acidic conditions. Transcriptomic analysis of pH regulated processes showed that important genes and BARD Report - Project 4773 Page 2 of 10 functionalities of P. expansumwere controlled by environmental pH. The differential expression patterns of genes belonging to the same gene family suggest that genes were selectively activated according to their optimal environmental conditions to enable the fungus to cope with varying conditions and to make optimal use of available enzymes. Concerning the second and third Aims, we demonstrated that LaeA regulates several secondary metabolite genes, including the PAT gene cluster and concomitant PAT synthesis invitro. Virulence studies of ΔlaeAmutants of two geographically distant P. expansumisolates (Pe-21 from Israel and Pe-T01 from China) showed differential reduction in disease severity in freshly harvested fruit ranging from no reduction for Ch-Pe-T01 strains in immature fruit to 15–25% reduction for both strains in mature fruit, with the ΔlaeAstrains of Is-Pe-21 always showing a greater loss in virulence. Results suggest the importance of LaeA regulation of PAT and other secondary metabolites on pathogenicity. Our work also characterized for the first time the role of sucrose, a key nutritional factor present in apple fruit, as a negative regulator of laeAexpression and consequent PAT production in vitro. This is the first report of sugar regulation of laeAexpression, suggesting that its expression may be subject to catabolite repression by CreA. Some, but not all of the 54 secondary metabolite backbone genes in the P. expansumgenome, including the PAT polyketide backbone gene, were found to be regulated by LaeA. Together, these findings enable for the first time a straight analysis of a host factor that potentially activates laeAand subsequent PAT synthesis.
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Borch, Thomas, Yitzhak Hadar, and Tamara Polubesova. Environmental fate of antiepileptic drugs and their metabolites: Biodegradation, complexation, and photodegradation. United States Department of Agriculture, January 2012. http://dx.doi.org/10.32747/2012.7597927.bard.

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Many pharmaceutical compounds are active at very low doses, and a portion of them regularly enters municipal sewage systems and wastewater-treatment plants following use, where they often do not fully degrade. Two such compounds, CBZ and LTG, have been detected in wastewater effluents, surface waters, drinking water, and irrigation water, where they pose a risk to the environment and the food supply. These compounds are expected to interact with organic matter in the environment, but little is known about the effect of such interactions on their environmental fate and transport. The original objectives of our research, as defined in the approved proposal, were to: Determine the rates, mechanisms and products of photodegradation of LTG, CBZ and selected metabolites in waters exposed to near UV light, and the influence of DOM type and binding processes on photodegradation. Determine the potential and pathways for biodegradation of LTG, CBZ and selected metabolites using a white rot fungus (Pleurotusostreatus) and ADP, and reveal the effect of DOM complexation on these processes. Reveal the major mechanisms of binding of LTG, CBZ and selected metabolites to DOM and soil in the presence of DOM, and evaluate the effect of this binding on their photodegradation and/or biodegradation. We determined that LTG undergoes relatively slow photodegradation when exposed to UV light, and that pH affects each of LTG’s ability to absorb UV light, the efficiency of the resulting reaction, and the identities of LTG’sphotoproducts (t½ = 230 to 500 h during summer at latitude 40 °N). We observed that LTG’sphotodegradation is enhanced in the presence of DOM, and hypothesized that LTG undergoes direct reactions with DOM components through nucleophilic substitution reactions. In combination, these data suggest that LTG’s fate and transport in surface waters are controlled by environmental conditions that vary with time and location, potentially affecting the environment and irrigation waters. We determined that P. ostreatusgrows faster in a rich liquid medium (glucose peptone) than on a natural lignocellulosic substrate (cotton stalks) under SSF conditions, but that the overall CBZ removal rate was similar in both media. Different and more varied transformation products formed in the solid state culture, and we hypothesized that CBZ degradation would proceed further when P. ostreatusand the ᵉⁿᶻʸᵐᵃᵗⁱᶜ ᵖʳᵒᶠⁱˡᵉ ʷᵉʳᵉ ᵗᵘⁿᵉᵈ ᵗᵒ ˡⁱᵍⁿⁱⁿ ᵈᵉᵍʳᵃᵈᵃᵗⁱᵒⁿ. ᵂᵉ ᵒᵇˢᵉʳᵛᵉᵈ ¹⁴C⁻Cᴼ2 ʳᵉˡᵉᵃˢᵉ ʷʰᵉⁿ ¹⁴C⁻ᶜᵃʳᵇᵒⁿʸˡ⁻ labeled CBZ was used as the substrate in the solid state culture (17.4% of the initial radioactivity after 63 days of incubation), but could not conclude that mineralization had occurred. In comparison, we determined that LTG does not degrade in agricultural soils irrigated with treated wastewater, but that P. ostreatusremoves up to 70% of LTG in a glucose peptone medium. We detected various metabolites, including N-oxides and glycosides, but are still working to determine the degradation pathway. In combination, these data suggest that P. ostreatuscould be an innovative and effective tool for CBZ and LTG remediation in the environment and in wastewater used for irrigation. In batch experiments, we determined that the sorption of LTG, CBZ and selected metabolites to agricultural soils was governed mainly by SOM levels. In lysimeter experiments, we also observed LTG and CBZ accumulation in top soil layers enriched with organic matter. However, we detected CBZ and one of its metabolites in rain-fed wheat previously irrigated with treated wastewater, suggesting that their sorption was reversible, and indicating the potential for plant uptake and leaching. Finally, we used macroscale analyses (including adsorption/desorption trials and resin-based separations) with molecular- level characterization by FT-ICR MS to demonstrate the adsorptive fractionation of DOM from composted biosolids by mineral soil. This suggests that changes in soil and organic matter types will influence the extent of LTG and CBZ sorption to agricultural soils, as well as the potential for plant uptake and leaching.
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Becher, Julie, Samuel Beal, Susan Taylor, Katerina Dontsova, and Dean Wilcox. Photo-transformation of aqueous nitroguanidine and 3-nitro-1,2,4-triazol-5-one : emerging munitions compounds. Engineer Research and Development Center (U.S.), August 2021. http://dx.doi.org/10.21079/11681/41743.

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Two major components of insensitive munition formulations, nitroguanidine (NQ) and 3-nitro-1,2,4-triazol-5-one (NTO), are highly water soluble and therefore likely to photo-transform while in solution in the environment. The ecotoxicities of NQ and NTO solutions are known to increase with UV exposure, but a detailed accounting of aqueous degradation rates, products, and pathways under different exposure wavelengths is currently lacking. We irradiated aqueous solutions of NQ and NTO over a 32-h period at three ultraviolet wavelengths and analyzed their degradation rates and transformation products. NQ was completely degraded by 30 min at 254 nm and by 4 h at 300 nm, but it was only 10% degraded after 32 h at 350 nm. Mass recoveries of NQ and its transformation products were >80% for all three wavelengths. NTO degradation was greatest at 300 nm with 3% remaining after 32 h, followed by 254 nm (7% remaining) and 350 nm (20% remaining). Mass recoveries of NTO and its transformation products were high for the first 8 h but decreased to 22–48% by 32 h. Environmental half-lives of NQ and NTO in pure water were estimated as 4 and 6 days, respectively. We propose photo-degradation pathways for NQ and NTO supported by observed and quantified degradation products and changes in solution pH.
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