3,455 research outputs found
Coevolution underlies GPCR-G protein selectivity and functionality
Get PDFG protein-coupled receptors (GPCRs) regulate diverse physiological events, which makes them as the major targets for many approved drugs. G proteins are downstream molecules that receive signals from GPCRs and trigger cell responses. The GPCR-G protein selectivity mechanism on how they properly and timely interact is still unclear. Here, we analyzed model GPCRs (i.e. HTR, DAR) and Gα proteins with a coevolutionary tool, statistical coupling analysis. The results suggested that 5-hydroxytryptamine receptors and dopamine receptors have common conserved and coevolved residues. The Gα protein also have conserved and coevolved residues. These coevolved residues were implicated in the molecular functions of the analyzed proteins. We also found specific coevolving pairs related to the selectivity between GPCR and G protein were identified. We propose that these results would contribute to better understandings of not only the functional residues of GPCRs and Gα proteins but also GPCR-G protein selectivity mechanisms. © 2021, The Author(s).1
The etiology of esophageal cancer in high- and low- risk areas of Jiangsu province, China
No full text [Background]Esophageal cancer (EC) remains one of the most common and fatal malignancies worldwide. The geographic variation in EC occurrence is striking, and China is an area with one of the highest incidences of EC. A number of epidemiological studies have been conducted toward EC in the past decades, results suggested that tobacco smoking, alcohol drinking, unhealthy dietary factors and chronic injuries of the esophageal mucosa are important in the development of this disease. Genetic polymorphisms in enzymes involved in metabolism of carcinogens may also influence individual susceptibility. However, the effects of major lifestyle and hereditary risk factors on the development of EC remain poorly understood in China. Moreover, little attention has been paid to the etiological heterogeneity between similar areas with great risk gradient. [Methods]From 2003 to 2007, a large population-based case-control study of EC has been conducted in a selected high-risk area and a selected low-risk area of Jiangsu Province, one of the highest cancer incidence areas in China. In total, 1,520 cases and 3,879 controls were recruited. In this thesis, we evaluated the role of major lifestyle factors such as tobacco smoking, alcohol drinking and dietary factors, as well as inherited determinants including family history of cancer and genetic polymorphisms of alcohol-metabolizing related genes on the risk of EC. In addition, we investigated how much of the risk gradient between two areas could be explained by variation in the distributions of major risk factors. [Results] Tobacco smoking and alcohol drinking moderately increased the risk of EC, while the positive associations were only found among men but not among women. Dietary factors were observed to play important roles in the development of EC. Specific dietary habits i.e., fast eating speed, and hot eating and/or drinking substantially elevated EC risk and could explain more than 20% of EC cases each. High intake of salty foods and fried foods, low consumption of raw garlic were also observed to increase the risk of EC. In addition to environmental and lifestyle factors, we confirmed that a positive family history can significantly increase EC risk, and found the inheritance may modify the effect of some unhealthy lifestyles. Moreover, we further explored the relationship between EC and single nucleotide polymorphismsof ADH1B, ADH1C and ALDH2 genes. Results showed that the slow metabolizing ADH1B G allele, ADH1C G allele and ALDH2 A allele significantly increased EC risk among moderate-to-heavy alcohol drinkers, and a significant interaction was observed between ALDH2 gene and alcohol consumption. Lastly, we found that more than 60% of EC cases could be attributable to major lifestyle risk factors in the study population; furthermore, dissimilar distribution of several lifestyle factors, together with variations of hereditary factors may be largely responsible for the incidence difference between two study areas. [Conclusion]The findings in this thesis confirm that unhealthy lifestyles including smoking, alcohol drinking and some dietary factors are the predominant risk factors of EC in China, and a large proportion of incidence difference between regions at varying risk could be attributed to the different prevalence of lifestyle factors. As most of the identified risk factors are modifiable, these could be translated into risk reduction prevention programs in China, and a substantial proportion of new EC cases are expected to be prevented by eliminating or avoiding these risk factors in the population. </p
An Archaeologist Celebrates his Jubilee: Yu. A. Zeleneev is 60
No full textThe article is devoted to the 60th birth anniversary of Yuri Anatolyevich Zeleneyev, Candidate of Historical Sciences, and Associate Professor of Mari State University. The principal spheres of his scientific interests and research activities include the archaeology of the Golden Horde period and medieval history of the peoples inhabiting the Volga region. Yu. A. Zeleneyev has coordinated research on many medieval sites, and his role in the study of the Golden Horde capital cities in the Lower Volga area should be particularly noted. Being among its founders, he headed the Center for archeological and ethnological research with Mari State University and organized rescue and salvage excavations in the Mari El Republic and adjacent territories. Yu. A. Zeleneyev is the author and coauthor of over 160 scientific and methodical works, editor of 9 collections of research papers, and deputy editor of the “Povolzhskaya Arkheologia” ("The Volga Region Archaeology") journal
The Author of the Hor-chos-ẖbyuṅ
No full textG. Huth, when translating the Hor-chos-ẖhbyuṅ (Geschichte des Buddhismus in der Mongolei, i, Strassburg, 1892), attributed this chronicle to ẖJigs-med nam-mkhaẖ, a high incarnate bLa-ma of the great bLa-bran bKra-śis-ẖkhyil monastery in the Amdo Province of North-Eastern Tibet. For over fifty years this attribution remained unchallenged, notwithstanding the fact that it is based on a wrong translation of the Tibetan text of the closing paragraphs of the chronicle. An attentive perusal of the Tibetan text shows that ẖJigs-med nam-mkhaẖ, whose short biography is given on p. 225 of the Tibetan text of the Hor-chos-ẖbyuṅ (ed. G. Huth), and on p. 356 of Huth's translation (Geschichte des Buddhismus in der Mongolei, ii, 1896), was not the author of the chronicle, but the inspirer of the work which was carried out at ẖJigs-med nam-mkhaẖ's command by Gu-śri (kuo-shih or State Preceptor) dKaẖ-bcu Su-dhī (Śuddhi) Ā-yu-warta (Āyurvarta), also known by the name of dbYaṅs-can sGeg-pahi blo-gros ẖJigsmed Rig-paẖi rdo-rje. The author of the chronicle met with ẖJigsmed nam-mkhaẖ during the latter's visit to the Barūn Türned principality in Eastern Mongolia (see Hor-chos-ẖbyuṅ, pp. 227–8). This ẖJigs-med nam-mkhah, better known by his title of Zam-tsha sku-zabs rin-po-che, was one of the “Four Golden Pillars” of bLa-bran in Amdo.1 Soon after A.D. 1803 (chu-phag lo, Water- Hog year) ẖJigs-med nam-mkhah was appointed to the abbot's chair (chos-khri) of the Yung Ho Kung () monastery in Peking. Later he was nominated tamaya lama (tha-ma-ka bla-ma) of Dolōn-nūr (mTsho-bdun) in Chakhar (E. Mongolia).</jats:p
Simulation models for the minimum velocity for foam generation and propagation
No full textFoam injection is a promising means of reducing the relative mobility of gas, and hence improving the sweep efficiency of gas, in CO2 and H2 storage, soil-contaminant removal in aquifer remediation, enhanced oil recovery, and matrix-acid well stimulation. Theory (Rossen and Gauglitz, 1990; Ashoori et al., 2012) and experiments (Gauglitz et al., 2002; Yu et al., 2019, 2020) indicate that both foam generation and propagation in steady flow in porous media require the attainment of a sufficiently large superficial velocity or pressure gradient ∇P. Here we examine several foam-simulation models for their ability to represent a minimum velocity, or trigger, for foam generation. We define criteria for representation of such a trigger. For simplicity, we assume a homogeneous porous medium and absence of an oleic phase. We examine the Population-Balance (PB) models of Kam and Rossen (2003) and one of its variants (Kam, 2008), and the PB model of Chen et al. (2010); and the implicit-texture (IT) models in CMG-STARS (Computer Modeling Group, 2017) and of Lotfollahi et al. (2017). Our result show that the PB models of Kam and Rossen and its variant, and the IT models of CMG-STARS and of Lotfollahi et al. do represent a minimum velocity for foam generation. They achieve this by modeling an abrupt decrease in gas mobility with increasing pressure gradient over some range of ∇P. The model of Chen et al. (2010) is based on the model of Kovscek and Radke (1996), which was not intended to represent a trigger for foam generation (Kovscek and Radke, 1993). We cannot say categorically whether it could predict a trigger for any set of model parameter values. Instead, we derive criteria that must be satisfied by the choice of parameters to represent a trigger for foam generation. In simulations of radial foam propagation the STARS foam model predicts that foam propagation fails at the radius at which local ∇P cannot maintain strong foam, not at a greater velocity and ∇P as seen in experiments (Yu et al., 2020). In addition, we identify a fundamental challenge in representing foam generation at the large ∇P at the wellbore in a numerical simulation: conventional simulators do not represent ∇P at the wellbore. Foam generation at the very high superficial velocity at the well radius is not represented in the absence of truly exceptional grid refinement.Reservoir Engineerin
Efficiency and durability of g-C<sub>3</sub>N<sub>4</sub>-based coatings applied on mortar under peeling and washing trials
No full textDurability of photocatalytic coatings is a major concern in engineering practice. Here, two types of novel visible light-responsive coatings, both consisting of vinyl chloride/vinyl ester/ethylene copolymer (as a binder) and graphitic carbon nitride (g-C3N4) but different in fabrication, are proposed and applied on the mortar surface. The first type is mono-layer coating (MC), where the g-C3N4 suspension containing the binder is directly sprayed on the mortar. The second type is double-layer coating (DC), where the binder layer is applied on mortar surface before spraying the g-C3N4 layer. Results show that the binder addition leads to a good anchorage of the coatings on both MC and DC mortar substrates, along with desirable resistance to peeling and washing, compared to the g-C3N4 coated mortar without the binder. The well-distributed binder in g-C3N4-based coating inevitably decreases the photocatalytic efficiency of the MC mortar due to masking effect of the binder on the coating surface. The DC mortar, on the contrary, takes full advantage of the binder adhesion by inserting a binder layer and therefore holds strong resistance to peeling and washing without compromising its photocatalytic efficiency. The proposed DC technique provides a promising strategy to fabricate highly cost-effective and durable photocatalytic coatings applied on cementitious materials.Accepted Author ManuscriptMaterials and Environmen
Letters from S. S. Bogatyrev to Yu. S. Meitus from Evacuation (1941–1942)
No full textСтатья поступила в редакцию 17.02.2015 г.В статье публикуются пять писем музыковеда, композитора и педагога С. С. Богатырева к своему ученику и коллеге композитору Ю. С . Мейтусу. Во время Великой Отечественной войны автор находился в эвакуации в Щучинске, Красноярске и Свердловске, где продолжал свою профессиональную деятельность. Тексты содержат сведения о творческой, профессиональной, лично-бытовой жизни музыкантов.The article publishes five letters of music expert, composer and teacher S. S. Bogatyrev to his student and colleague composer Yu. S. Meitus. During the Great Patriotic War, the author was evacuated to Shchuchinsk, Krasnoyarsk and Sverdlovsk where he continued his work. The texts provide information on the artistic, professional and personal life of the musicians
Appropriations of Irish drama by modern Korean nationalist theatre : a focus on the influence of Sean O’Casey in a colonial context
Get PDFMy thesis explores how a translated author on the periphery of the host culture’s
translated repertoire can be at once subversive and innovative on the colonial scene,
using as an example the case of Sean O’Casey in colonial Korea. It explores the
importation of Irish drama in modern Korean theatre during the colonial period and
examines the appropriations of O’Casey’s plays by a central Korean playwright, Yu
Chi-jin, in creating his own plays. Under Japanese colonial rule in the early twentieth
century, intellectuals perceived the supreme task for the Korean people to be the
recovery of national sovereignty and independence. The modern Korean theatre
movement which rose among Korean intellectuals and dramatists during the colonial
period was to play a major part in this task. The ultimate goal of this movement was
to establish a modern national theatre promoting Korean culture and educating the
people, thereby recovering national independence. As their modernised dramatic
polysystem was still "young", Korean intellectuals and dramatists who were
involved in the theatre movement had to borrow dramatic models from other
countries. One of the models they chose was Irish playwrights, especially those who
were involved in the Irish dramatic movement. They published or staged the works
of W.B. Yeats, Lord Dunsany [Edward John Moreton Drax Plunkett], Augusta
Gregory, J.M. Synge, St. J. Ervine, T.C. Murray and Sean O'Casey. Although
O'Casey was considered an important dramatist in the Irish dramatic movement, he
was a playwright on the periphery in the list of translated Irish dramatists in Korea
due to the colonisers’ censorship. However, he remained as a subversive and
innovative playwright on the colonial scene by virtue of being appropriated by Yu
Chi-jin who used O’Casey’s plays as models when creating his own works. In
discussing the subject matter of my thesis, I use Even Zohar’s polysystems theory as
a starting point in looking at ideological issues surrounding translation and extend
the discussion to offer a postcolonial perspective. While most translation in a
colonial context was considered as "an expression of the cultural power of the
colonisers," my thesis shifts the focus to translation as an expression of the cultural
power of the colonised. I explore how the colonised uses another colonised culture to
subvert the colonisers’ power
[[alternative]]Effects of G-CSF on neuropathic pain of rats with chronic constriction
No full text[[abstract]]Neuropathic pain is due to long-term dysfunction of the nervous system and is difficult to managements and treatments. Under inflammatory conditions, leukocytes secrete opioid peptides, which bind to opioid receptors on peripheral sensory neurons and mediate antinociception. The majority of opioid-containing leukocytes are PMN during early inflammation. Granulocyte-colony stimulating factor (G-CSF) is a particular growth factor that works by encouraging the bone marrow to produce more stem cells which then differentiate into white blood cells, especially the PMN. Therefore, G-CSF has a potential to become an anti-nociceptive agent. In the study we use chronic constriction injury model to produce neuropathic pain in rats with nerve injury. Thereafter, we performed behavior tests including thermal and mechanical responses. Our results indicated the experimental group with i.v. G-CSF showed less severe neuropathic pain than control with normal saline within 2 days post-operation. In flow cytometry and immuno-histochemical studies the numbers of PMN cells around sciatic nerve in the group with G-CSF treatment showed much more than the control group. The results demonstrated the effects of G-CSF on neuropathic pain are probably through the opioid compounds secreted by PMN cells. Besides, we find that G-CSF maybe inhabit the expression of several proinflammatory cytokine, like IL-1β and IL-6 by SQ-RT-PCR. So the mechanism of G-CSF to save pain may not only due to the opioid compound secreted by PMN cells but inhabit the expression of IL-1βand IL-6 to suppress the inflammatory and neuropathic pain.
Ammonium removal and recovery from wastewater with porous geopolymers
Get PDFAbstract
Porous geopolymer granules are emerging as a promising material for high-value applications such as adsorption and ammonium (NH₄⁺) recovery from wastewater. This thesis presents a comprehensive investigation into the fabrication, characterization, and application of porous metakaolin-based geopolymer granules produced via direct foaming, one-part alkali activation, and high-shear granulation. Porosity was introduced using either hydrogen peroxide (H₂O₂) or municipal solid waste incineration fly ash containing metallic aluminum (Al0) as blowing agents. Increased porosity, particularly in the micro- and nanoscale range, significantly enhanced the specific surface area and NH₄⁺ adsorption capacity—up to 126% higher compared to nonporous granules, with optimal performance observed using 10% H₂O₂ solution. The granules demonstrated sufficient mechanical strength (≥2 MPa) and were evaluated for environmental safety and ion-exchange behavior. While fly ash improved porosity, it introduced leaching concerns for elements like antimony and vanadium, limiting its optimal content to 0.3 wt.% Al0. Adsorption-desorption studies showed that porous geopolymer granules achieved an average NH₄⁺ uptake capacity of up to 9.0 mg/g, and NH₄⁺ recovery of 51–98% over the 30 adsorption and desorption cycles using KNO₃ as a regenerant, though performance declined after 20 cycles. Application in municipal wastewater highlighted the need for pretreatment to mitigate pore blocking and surface fouling. Overall, these findings establish porous geopolymer granules as a feasible, regenerable, and effective material for NH₄⁺ recovery, contributing to circular nitrogen economy and sustainable wastewater treatment strategies. Original papers Yu, Y., Perumal, P., Corfe, I. J., Paul, T., Illikainen, M., & Luukkonen, T. (2023). Combined granulation–alkali activation–direct foaming process: A novel route to porous geopolymer granules with enhanced adsorption properties. Materials & Design, 227, 111781. https://doi.org/10.1016/j.matdes.2023.111781 https://doi.org/10.1016/j.matdes.2023.111781 Self-archived version Luukkonen, T., Yu, Y., Adhikary, S. K., Kauppinen, S., Finnilä, M., & Perumal, P. (2024). Metallic aluminium in municipal solid waste incineration fly ash as a blowing agent for porous alkali-activated granules. Royal Society Open Science, 11(8), 240598. https://doi.org/10.1098/rsos.240598 https://doi.org/10.1098/rsos.240598 Self-archived version Yu, Y., Perumal, P., Sithole, T., & Luukkonen, T. (2025). Recovery of ammonium and nitrate from wastewater using adsorption-based techniques: A review. Journal of Cleaner Production, 519, 145976. https://doi.org/10.1016/j.jclepro.2025.145976 https://doi.org/10.1016/j.jclepro.2025.145976 Self-archived version Yu, Y., Bhuyan, M., Perumal, P., Luukkonen, T. (2025). Ammonium removal and recovery from municipal wastewater by ion exchange using porous metakaolin geopolymer granules. Manuscript submitted for publication. Tiivistelmä
Huokoiset geopolymeerirakeet ovat nousemassa lupaavaksi materiaaliksi korkean lisäarvon sovelluksiin, kuten adsorptioon ja ammoniumin (NH₄⁺) talteenottoon jätevedestä. Tämä väitöskirja esittelee kattavan tutkimuksen metakaoliinipohjaisten huokoisten geopolymeerirakeiden valmistuksesta, karakterisoinnista ja käytöstä hyödyntäen vaahdotusta, alkaliaktivointia sekä granulointia. Huokoisuutta lisättiin käyttämällä vaahdotusaineina joko vetyperoksidia (H₂O₂) tai yhdyskuntajätteenpolton lentotuhkaa, joka sisälsi metallista alumiinia (Al0). Huokoisuuden lisääntyminen, erityisesti mikro- ja nanokokoluokissa, paransi merkittävästi rakeiden ominaispinta-alaa ja NH₄⁺-adsorptiokapasiteettia – jopa 126 % verrattuna ei-huokoisiin rakeisiin. Paras suorituskyky saavutettiin 10 % H₂O₂-liuoksella. Rakeet osoittivat riittävää mekaanista lujuutta (≥2 MPa), ja niitä arvioitiin myös ioninvaihtokyvyn osalta. Vaikka lentotuhka lisäsi huokoisuutta, se aiheutti haitallisten aineiden, kuten antimonin ja vanadiinin, liukenemista, minkä vuoksi optimaalinen tuhkapitoisuus rajoitettiin 0.3 paino-% Al0:aan. Adsorptio-desorptiotutkimukset osoittivat, että huokoiset geopolymeerirakeet saavuttivat keskimääräisen NH₄⁺-ottokapasiteetin jopa 9.0 mg/g ja NH₄⁺-saannon 51–98 % 30 adsorptio- ja desorptiosyklin aikana, kun KNO3 20:a regeneroivana aineena käytettiin, vaikka suorituskyky heikkeni syklin jälkeen. Pitkän aikavälin käytössä suorituskyky kuitenkin heikkeni. Kunnallisen jäteveden käsittelyssä havaittiin huokosten tukkeutumista ja pintaan kertyvää kiintoainesta, mikä korostaa esikäsittelyn merkitystä. Yhteenvetona voidaan todeta, että huokoiset geopolymeerirakeet ovat käyttökelpoinen, uudelleenkäytettävä ja tehokas materiaali NH₄⁺:n talteenottoon, edistäen typen kiertotaloutta ja kestävää jäteveden käsittelyä. Osajulkaisut Yu, Y., Perumal, P., Corfe, I. J., Paul, T., Illikainen, M., & Luukkonen, T. (2023). Combined granulation–alkali activation–direct foaming process: A novel route to porous geopolymer granules with enhanced adsorption properties. Materials & Design, 227, 111781. https://doi.org/10.1016/j.matdes.2023.111781 https://doi.org/10.1016/j.matdes.2023.111781 Rinnakkaistallennettu versio Luukkonen, T., Yu, Y., Adhikary, S. K., Kauppinen, S., Finnilä, M., & Perumal, P. (2024). Metallic aluminium in municipal solid waste incineration fly ash as a blowing agent for porous alkali-activated granules. Royal Society Open Science, 11(8), 240598. https://doi.org/10.1098/rsos.240598 https://doi.org/10.1098/rsos.240598 Rinnakkaistallennettu versio Yu, Y., Perumal, P., Sithole, T., & Luukkonen, T. (2025). Recovery of ammonium and nitrate from wastewater using adsorption-based techniques: A review. Journal of Cleaner Production, 519, 145976. https://doi.org/10.1016/j.jclepro.2025.145976 https://doi.org/10.1016/j.jclepro.2025.145976 Rinnakkaistallennettu versio Yu, Y., Bhuyan, M., Perumal, P., Luukkonen, T. (2025). Ammonium removal and recovery from municipal wastewater by ion exchange using porous metakaolin geopolymer granules. Manuscript submitted for publication. Academic dissertation to be presented with the assent of the Doctoral Programme Committee of Technology and Natural Sciences of the University of Oulu for public defence in the Oulun Puhelin auditorium (L5), Linnanmaa, on 10 October 2025, at 12 noonAbstract
Porous geopolymer granules are emerging as a promising material for high-value applications such as adsorption and ammonium (NH₄⁺) recovery from wastewater. This thesis presents a comprehensive investigation into the fabrication, characterization, and application of porous metakaolin-based geopolymer granules produced via direct foaming, one-part alkali activation, and high-shear granulation. Porosity was introduced using either hydrogen peroxide (H₂O₂) or municipal solid waste incineration fly ash containing metallic aluminum (Al0) as blowing agents. Increased porosity, particularly in the micro- and nanoscale range, significantly enhanced the specific surface area and NH₄⁺ adsorption capacity—up to 126% higher compared to nonporous granules, with optimal performance observed using 10% H₂O₂ solution. The granules demonstrated sufficient mechanical strength (≥2 MPa) and were evaluated for environmental safety and ion-exchange behavior. While fly ash improved porosity, it introduced leaching concerns for elements like antimony and vanadium, limiting its optimal content to 0.3 wt.% Al0. Adsorption-desorption studies showed that porous geopolymer granules achieved an average NH₄⁺ uptake capacity of up to 9.0 mg/g, and NH₄⁺ recovery of 51–98% over the 30 adsorption and desorption cycles using KNO₃ as a regenerant, though performance declined after 20 cycles. Application in municipal wastewater highlighted the need for pretreatment to mitigate pore blocking and surface fouling. Overall, these findings establish porous geopolymer granules as a feasible, regenerable, and effective material for NH₄⁺ recovery, contributing to circular nitrogen economy and sustainable wastewater treatment strategies.Tiivistelmä
Huokoiset geopolymeerirakeet ovat nousemassa lupaavaksi materiaaliksi korkean lisäarvon sovelluksiin, kuten adsorptioon ja ammoniumin (NH₄⁺) talteenottoon jätevedestä. Tämä väitöskirja esittelee kattavan tutkimuksen metakaoliinipohjaisten huokoisten geopolymeerirakeiden valmistuksesta, karakterisoinnista ja käytöstä hyödyntäen vaahdotusta, alkaliaktivointia sekä granulointia. Huokoisuutta lisättiin käyttämällä vaahdotusaineina joko vetyperoksidia (H₂O₂) tai yhdyskuntajätteenpolton lentotuhkaa, joka sisälsi metallista alumiinia (Al0). Huokoisuuden lisääntyminen, erityisesti mikro- ja nanokokoluokissa, paransi merkittävästi rakeiden ominaispinta-alaa ja NH₄⁺-adsorptiokapasiteettia – jopa 126 % verrattuna ei-huokoisiin rakeisiin. Paras suorituskyky saavutettiin 10 % H₂O₂-liuoksella. Rakeet osoittivat riittävää mekaanista lujuutta (≥2 MPa), ja niitä arvioitiin myös ioninvaihtokyvyn osalta. Vaikka lentotuhka lisäsi huokoisuutta, se aiheutti haitallisten aineiden, kuten antimonin ja vanadiinin, liukenemista, minkä vuoksi optimaalinen tuhkapitoisuus rajoitettiin 0.3 paino-% Al0:aan. Adsorptio-desorptiotutkimukset osoittivat, että huokoiset geopolymeerirakeet saavuttivat keskimääräisen NH₄⁺-ottokapasiteetin jopa 9.0 mg/g ja NH₄⁺-saannon 51–98 % 30 adsorptio- ja desorptiosyklin aikana, kun KNO3 20:a regeneroivana aineena käytettiin, vaikka suorituskyky heikkeni syklin jälkeen. Pitkän aikavälin käytössä suorituskyky kuitenkin heikkeni. Kunnallisen jäteveden käsittelyssä havaittiin huokosten tukkeutumista ja pintaan kertyvää kiintoainesta, mikä korostaa esikäsittelyn merkitystä. Yhteenvetona voidaan todeta, että huokoiset geopolymeerirakeet ovat käyttökelpoinen, uudelleenkäytettävä ja tehokas materiaali NH₄⁺:n talteenottoon, edistäen typen kiertotaloutta ja kestävää jäteveden käsittelyä
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