Artículos de revistas: "S-PEG"

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Assem, Yasser, Heba A. Mohamed, Rana Said y Ahmed El-Masry. "Preparation of amphiphilic block copolymers (polyethylene adipate-block-polyethylene glycol) and its application in rotogravure ink formulations". Pigment & Resin Technology 47, n.º 5 (3 de septiembre de 2018): 415–23. http://dx.doi.org/10.1108/prt-02-2017-0020.

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Purpose The purpose of this paper is to prepare amphiphilic block copolymers polyethylene adipate-block-polyethylene glycol (PEA-b-PEG)s and study their performance as plasticizers in rotogravure ink formulations. Design/methodology/approach Series of amphiphilic block copolymers (PEA-b-PEG1), (PEA-b-PEG2), (PEA-b-PEG3), (PEA-b-PEG4) and (PEA-b-PEG5) were prepared by the reaction of adipic acid, ethylene glycol and polyethylene glycol of different molecular weights (300, 1,000, 2,000, 10,000 and 20,000 g/mol), respectively. Full characterization of the prepared copolymers was achieved using Fourier Transfer Infrared Spectroscopy (FTIR), 1H NMR, thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). The performance of the prepared copolymers as plasticizers for neat nitrocellulose resin were studied in different formulations, namely, R1, R2, R3, R4 and R5 containing copolymers (PEA-b-PEG1), (PEA-b-PEG2), (PEA-b-PEG3), (PEA-b-PEG4) and (PEA-b-PEG5), respectively. In addition to formula R0 that contains acetyl tributyl citrate (ATBC) as a commercial plasticizer. The mechanical properties, thermal analysis (DSC, TGA) and optical properties of the prepared formulations films were investigated. Theses amphiphilic block copolymers were then applied as plasticizers in different rotogravure ink formulations (F1, F2, F3, F4 and F5) and compared with commercial rotogravure ink formula (F0). The color measurements and optical properties of all formulations were achieved. Findings It was found that the performance of the prepared copolymers as plasticizers in different formulations based on nitro cellulose resin gives better gloss, adhesion for R1 compared with the other samples and color strength for F1 compared with F0. Finally, all the samples gave excellent plasticizing effect. Research limitations/implications The authors believe that type of these materials open the way for a new class of plasticizers that upon application or even degradation gives small ecofriendly molecules (adipic acid and or ethylene glycol moieties) taking into consideration the simplicity of the rout of the synthesis process. Practical implications The prepared ecofriendly (PEA-b-PEG)s could be successfully used as plasticizers instead of commercial plasticizer ATBC. Originality/value The research provides that the prepared (PEA-b-PEG)s with different molecular weights can act as plasticizers in rotogravure ink formulations, and their performance was acceptable and available.

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Majumdar, Abdullah-Al-Kafi. "The Reve’s Puzzle Revisited". Proceedings of the Pakistan Academy of Sciences: A. Physical and Computational Sciences 58, n.º 2 (24 de diciembre de 2021): 11–18. http://dx.doi.org/10.53560/ppasa(58-2)585.

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The Reve’s puzzle, introduced by the English puzzlist, H.E. Dudeney, is a mathematical puzzle with 10 discs of different sizes and four pegs, designated as S, P1, P2 and D. Initially, the n (  1) discs rest on the source peg, S, in a tower (with the largest disc at the bottom and the smallest disc at the top). The objective is to move the tower from the peg S to the destination peg D, in a minimum number of moves, under the condition that each move can transfer only one disc from one peg to another such that no disc can ever be placed on top of a smaller one. This paper considers the solution of the dynamic programming equation corresponding to the Reve’s puzzle.

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Zhang, Hong, Qian Qian Wang, Heng Xue Xiang y Xiao Lei Wang. "Study on Polyethylene Glycol Acrylate Crosslinked Gels as Phase Change Materials". Advanced Materials Research 299-300 (julio de 2011): 649–53. http://dx.doi.org/10.4028/www.scientific.net/amr.299-300.649.

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The cross-linking degree of polyethylene glycol acrylate (PEGA) gel by free-radical solution polymerization was investigated in which PEGA was prepared by chemical modification. The structural morphology, crystal property, thermal property and thermostability were investigated using scanning electron microscope (SEM), polarization microscope (POM), differential scanning calorimeter (DSC), and thermogravimetric analysis (TG), respectively. The results showed that the chain segment of PEG had good activity in lightly cross-linked PEGA gel, the crystallization enthalpy of PEGA gel achieved to 122 J/g, and the duration of its soaking time was about 490 s. Furthermore, chain segment of PEG were bound in PEGA gel, but the crystallization enthalpy of PEGA gel achieved to 64.60 J/g, its soaking time was continued for about 430 s. PEGA gel had a better thermal stability below 300 °C.

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Majumdar, AAK. "On the Star Puzzle". GANIT: Journal of Bangladesh Mathematical Society 39 (19 de noviembre de 2019): 1–14. http://dx.doi.org/10.3329/ganit.v39i0.44158.

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In the star puzzle, there are four pegs, the usual three pegs, S, P and D, and a fourth one at 0. Starting with a tower of n discs on the peg P, the objective is to transfer it to the peg D, in minimum number of moves, under the conditions of the classical Tower of Hanoi problem and the additional condition that all disc movements are either to or from the fourth peg. Denoting by MS(n) the minimum number of moves required to solve this variant, MS(n) satisfies the recurrence relation . This paper studies rigorously and extensively the above recurrence relation, and gives a solution of it. GANIT J. Bangladesh Math. Soc.Vol. 39 (2019) 1-14

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Xi, Li Peng, Li Dong Hong, Wan Chuan y Chen Ben Shou. "Design, Synthesis, and Biological Activity of Releasable m-THPC-PEGfolate Conjugate Using a Disulfide-containing Linker". Letters in Organic Chemistry 16, n.º 3 (11 de febrero de 2019): 165–69. http://dx.doi.org/10.2174/1570178615666181003124619.

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The present study reported the preparation of a novel mutual prodrug containing meso-tetra (m-hydroxy phenyl) chlorin (m-THPC), PEG and folate. The folate receptor (FR) targeting compound is a water-soluble chemical incorporating a hydrophilic PEG spacer unit and a reducible selfimmolative disulfide-based linker system between the FR-targeting ligand and the chlorin. The m- THPC-s-s-PEG-Folate was proved to release the parent drug and exhibited significant targeting effects on HeLa cells. In addition, the redox-responsive folate targeting photosensitizer m-THPC-s-s-PEG-Folate showed slightly higher phototoxicity than m-THPC-PEG-Folate for HeLa cells.

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Gris, Jean-Christophe, Pierre Toulon, Sophie Brun, Claude Maugard, Christian Sarlat, Jean-François Schved y Jocques Berlan. "The Relationship between Plasma Microparticles, Protein S and Anticardiolipin Antibodies in Patients with Human Immunodeficiency Virus Infection". Thrombosis and Haemostasis 76, n.º 01 (1996): 038–45. http://dx.doi.org/10.1055/s-0038-1650519.

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SummaryThe high prevalence of free protein S deficiency in human immunodeficiency virus (HlV)-infected patients is poorly understood. We studied 38 HIV seropositive patients. Free protein S antigen values assayed using the polyethylene-glycol precipitation technique (PEG-fS) were statistically lower in patients than in controls. These values using a specific monoclonal antibody-based ELISA (MoAb-fS) and the values of protein S activity (S-act) were not statistically different between patients and controls. C4b-binding protein values were not different from control values. In patients, PEG-fS values were lower than MoAb-fS values. Ten patients had a PEG-fS deficiency, 4 patients had a MoAb-fS deficiency and 8 had a S-act deficiency. Protein S activity and MoAb-fS were lower in clinical groups with poor prognosis and in patients with AIDS but PEG-fS was not. A trend for reduced S-act/MoAb-fS ratios was observed in patients. PEG-fS was negatively correlated with anticardiolipin antibody titers whereas MoAb-fS was not. The plasma of PEG-fS deficient HIV-patients contained high amounts of flow cytometry detectable microparticles which were depleted from plasma by PEG precipitation. The microparticles were partly CD42b and CD4 positive but CD8 negative. These microparticles were labelled by an anti free protein S monoclonal antibody. The observed differences between MoAb-fS and PEG-fS values were correlated with the amount of detectable plasma microparticles, just like the differences between MoAb-fS and S-act. Plasma microparticles correlated with anticardiolipin antibody titers.In summary, free protein S antigen in HIV infected patients is underestimated when the PEG precipitation technique is used due to the presence of elevated levels of microparticles that bind protein S. The activity of free protein S is also impaired by high levels of microparticles. The prevalence of free protein S deficiency in HIV positive patients is lower than previously published (4/38, -10%) and is correlated with poor prognosis. By implication, use of a PEG precipitation technique might give artefactually low free protein S antigen values in other patient groups if high numbers of microparticles are present. In HIV patients, high titers of anticardiolipin antibodies are associated with high concentrations of cell-derived plasma microparticles.

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Li, Xiaodong, Meishuai Zou, Lisha Lei y Longhao Xi. "Non-Isothermal Crystallization Kinetics of Poly(ethylene glycol) and Poly(ethylene glycol)-B-Poly(ε-caprolactone) by Flash DSC Analysis". Polymers 13, n.º 21 (27 de octubre de 2021): 3713. http://dx.doi.org/10.3390/polym13213713.

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The non-isothermal crystallization behaviors of poly (ethylene glycol) (PEG) and poly (ethylene glycol)-b-poly(ε-caprolactone) (PEG-PCL) were investigated through a commercially available chip-calorimeter Flash DSC2+. The non-isothermal crystallization data under different cooling rates were analyzed by the Ozawa model, modified Avrami model, and Mo model. The results of the non-isothermal crystallization showed that the PCL block crystallized first, followed by the crystallization of the PEG block when the cooling rate was 50–200 K/s. However, only the PEG block can crystallize when the cooling rate is 300–600 K/s. The crystallization of PEG-PCL is completely inhibited when the cooling rate is 1000 K/s. The modified Avrami and Ozawa models were found to describe the non-isothermal crystallization processes well. The growth methods of PEG and PEG-PCL are both three-dimensional spherulitic growth. The Mo model shows that the crystallization rate of PEG is greater than that of PEG-PCL.

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Huang, Shuman, Pengpeng Ding, Sha Liu, Chang Li, Yaqian Zhang, Dong Dong y Yulin Zhao. "ISMN-loaded PLGA-PEG nanoparticles conjugated with anti-Staphylococcus aureus α-toxin inhibit Staphylococcus aureus biofilms in chronic rhinosinusitis". Future Medicinal Chemistry 13, n.º 23 (diciembre de 2021): 2033–46. http://dx.doi.org/10.4155/fmc-2021-0126.

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Background: Staphylococcus aureus biofilms were linked to negative postsurgical outcomes of chronic rhinosinusitis (CRS). This study aims to develop a targeted nanoparticle and characterize its bactericidal effects. Methods: The authors prepared ISMN-loaded poly-lactide-co-glycolide acid (PLGA) and polyethylene glycol (PEG) nanoparticles conjugated with anti- S. aureus α-toxin (AA; ISMN-PLGA-PEG-AA), and determined its bactericidal and toxic effects. The antibiofilm propriety of ISMN-PLGA-PEG-AA was further investigated in a sheep CRS model. Results: ISMN-PLGA-PEG-AA had no toxic effect, while ISMN, ISMN-PLGA-PEG and ISMN-PLGA-PEG-AA had significantly anti- S. aureus effects. The blood concentrations and mRNA levels in sinus tissues of IL-4, IL-8 and IFN-γ in the sheep CRS model were significantly low. Conclusion: ISMN-PLGA-PEG-AA can effectively inhibit S. aureus biofilm, and is a promising drug for CRS treatment.

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Zhu, Chunyan, Yunchang Fan y Xiujun Bai. "A Green and Effective Polyethylene Glycols-Based Microwave-Assisted Extraction of Carnosic and Rosmarinic Acids from Rosmarinus officinalis Leaves". Foods 12, n.º 9 (24 de abril de 2023): 1761. http://dx.doi.org/10.3390/foods12091761.

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Rosmarinus officinalis leaves (ROLs) are widely used as a popular culinary spice for flavoring food, in which carnosic acid (CA) and rosmarinic acid (RA) are the main active components. The extraction of CA and RA is limited by lowextraction efficiency and extraction rate. In this work, a microwave-assisted extraction (MAE) method using biodegradable, low-toxic and nonflammable solvents polyethylene glycols (PEGs) as extraction solvents was developed for theextraction of CA and RA from ROLs. Experimental results suggest that PEG-400 was a better choice compared with PEG-200, and the optimal extraction conditions were as follows: 45% of PEG-400, 4.3% of phosphoric acid, 20 s of microwave irradiation time at 280 W of microwave irradiation power, and a 10 mg mL−1 solid–liquid ratio, respectively. The tissue structures of ROLs could be effectively disrupted by PEG-based MAE, leading to high CA and RA extraction efficiencies. The PEG-400 extract exhibited stronger 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability compared with butylated hydroxytoluene (BHT). Finally, compared with heating reflux extraction, ultrasound-assisted extraction, maceration, and MAE using ionic liquid and ethanol as extraction solvents, the developed PEG-400 based MAE exhibited the highest extraction ability and fastest extraction rate for CA and RA. These findings suggest that MAE using PEGs as extraction solvents is a promising method for the separation of bioactive compounds from natural plants.

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Shimotoyodome, Akira, Takashi Koudate, Hisataka Kobayashi, Junji Nakamura, Ichiro Tokimitsu, Tadashi Hase, Takashi Inoue, Takashi Matsukubo y Yoshinori Takaesu. "Reduction of Streptococcus mutans Adherence and Dental Biofilm Formation by Surface Treatment with Phosphorylated Polyethylene Glycol". Antimicrobial Agents and Chemotherapy 51, n.º 10 (23 de julio de 2007): 3634–41. http://dx.doi.org/10.1128/aac.00380-07.

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ABSTRACT Initial attachment of the cariogenic Streptococcus mutans onto dental enamel is largely promoted by the adsorption of specific salivary proteins on enamel surface. Some phosphorylated salivary proteins were found to reduce S. mutans adhesion by competitively inhibiting the adsorption of S. mutans-binding salivary glycoproteins to hydroxyapatite (HA). The aim of this study was to develop antiadherence compounds for preventing dental biofilm development. We synthesized phosphorylated polyethylene glycol (PEG) derivatives and examined the possibility of surface pretreatment with them for preventing S. mutans adhesion in vitro and dental biofilm formation in vivo. Pretreatment of the HA surface with methacryloyloxydecyl phosphate (MDP)-PEG prior to saliva incubation hydrophilized the surface and thereby reduced salivary protein adsorption and saliva-promoted bacterial attachment to HA. However, when MDP-PEG was added to the saliva-pretreated HA (S-HA) surface, its inhibitory effect on bacterial binding was completely diminished. S. mutans adhesion onto S-HA was successfully reduced by treatment of the surface with pyrophosphate (PP), which desorbs salivary components from S-HA. Treatment of S-HA surfaces with MDP-PEG plus PP completely inhibited saliva-promoted S. mutans adhesion even when followed by additional saliva treatment. Finally, mouthwash with MDP-PEG plus PP prevented de novo biofilm development after thorough teeth cleaning in humans compared to either water or PP alone. We conclude that MDP-PEG plus PP has the potential for use as an antiadherence agent that prevents dental biofilm development.

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Pritchard, DA, PR Martin y PK O'Rourke. "The role of condensed tannins in the nutritional value of mulga (Acacia aneura) for sheep". Australian Journal of Agricultural Research 43, n.º 8 (1992): 1739. http://dx.doi.org/10.1071/ar9921739.

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Sheep were fed mulga (Acacia aneura) ad libitum and supplemented with 0, 12 or 24 g/day of polyethylene glycol molecular weight 4000 (PEG), with or without an additional supplement of 1.5 g/day of each of nitrogen (N), phosphorus (P) and sulfur (S) (NPS). Supplementation with either 12 g/day PEG or 24 g/day PEG increased dry matter intake by 56 and 78% respectively and clean wool growth per unit surface area by 166 and 178% respectively. Supplementation with 24 g/day PEG increased wool fibre diameter, linear growth rate and volumetric growth rate by 32, 29 and 143% respectively. Sheep receiving 24 g/day PEG retained more N (1.80 g/day) and S (254 mg/day) and digested more N (218 g/kg) and S (229 g/kg) when compared with non-supplemented animals. These parameters were further enhanced when NPS was supplemented in conjunction with 24 g/day PEG. Maximum precipitation (77%) of mulga condensed tannins (CT) occurred at a PEG to CT ratio of 0.7:l.

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Wang, Guanchao, Yanqing Lai, Zhian Zhang, Jie Li y Zhiyong Zhang. "Enhanced rate capability and cycle stability of lithium–sulfur batteries with a bifunctional MCNT@PEG-modified separator". Journal of Materials Chemistry A 3, n.º 13 (2015): 7139–44. http://dx.doi.org/10.1039/c4ta07133f.

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Baimark, Yodthong, Wuttipong Rungseesantivanon y Natcha Prakymoramas. "The Effect of Mold Conditions on Heat Resistance of Injection-Molded Stereocomplex Polylactide-b-polyethylene Glycol-b-Polylactide Bioplastic". Materiale Plastice 58, n.º 3 (5 de octubre de 2021): 11–22. http://dx.doi.org/10.37358/mp.21.3.5499.

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The effect of mold conditions was investigated in terms of mold temperature (30oC and 90oC) and cooling time (30 s and 60 s) on the heat resistance of injection-molded bars for stereocomplex polylactide-b-polyethylene glycol-b-polylactide (scPLA-PEG-PLA). Comparative study was performed for poly(L-lactide) (PLLA) and PLLA-b-PEG-b-PLLA (PLLA-PEG-PLLA). scPLA-PEG-PLA was 90/10 (w/w) PLLA-PEG-PLLA/poly(D-lactide) blend. scPLA-PEG-PLA exhibited the easiest crystallization upon cooling scan as shown by differential scanning calorimetry (DSC). Higher mold-temperature and longer cooling-time induced higher degree of crystallinity as assessed by X-ray diffractometry (XRD) except for PLLA bars. The heat resistance of both PLLA-PEG-PLLA and scPLA-PEG-PLA bars was improved with increased mold-temperature and cooling-time as shown by dynamic mechanical analysis (DMA), vicat softening temperature (VST) and heat distortion-resistance tests except for PLLA bars. In conclusion, the heat resistance of injection-molded bars prepared at 90˚C mold temperature was in the order scPLA-PEG-PLA ] PLLA-PEG-PLLA ] PLLA. The results suggested that flexible PLLA-PEG-PLLA and scPLA-PEG-PLA with high degrees of crystallinity were successfully obtained by injection molding for use as good heat-resistant bioplastic products.

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Baimark, Yodthong, Wuttipong Rungseesantivanon y Natcha Prakymoramas. "The Effect of Mold Conditions on Heat Resistance of Injection-Molded Stereocomplex Polylactide-b-polyethylene Glycol-b-Polylactide Bioplastic". Materiale Plastice 58, n.º 3 (5 de octubre de 2021): 11–22. http://dx.doi.org/10.37358/mp.21.3.5499.

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The effect of mold conditions was investigated in terms of mold temperature (30oC and 90oC) and cooling time (30 s and 60 s) on the heat resistance of injection-molded bars for stereocomplex polylactide-b-polyethylene glycol-b-polylactide (scPLA-PEG-PLA). Comparative study was performed for poly(L-lactide) (PLLA) and PLLA-b-PEG-b-PLLA (PLLA-PEG-PLLA). scPLA-PEG-PLA was 90/10 (w/w) PLLA-PEG-PLLA/poly(D-lactide) blend. scPLA-PEG-PLA exhibited the easiest crystallization upon cooling scan as shown by differential scanning calorimetry (DSC). Higher mold-temperature and longer cooling-time induced higher degree of crystallinity as assessed by X-ray diffractometry (XRD) except for PLLA bars. The heat resistance of both PLLA-PEG-PLLA and scPLA-PEG-PLA bars was improved with increased mold-temperature and cooling-time as shown by dynamic mechanical analysis (DMA), vicat softening temperature (VST) and heat distortion-resistance tests except for PLLA bars. In conclusion, the heat resistance of injection-molded bars prepared at 90˚C mold temperature was in the order scPLA-PEG-PLA ] PLLA-PEG-PLLA ] PLLA. The results suggested that flexible PLLA-PEG-PLLA and scPLA-PEG-PLA with high degrees of crystallinity were successfully obtained by injection molding for use as good heat-resistant bioplastic products.

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Mhessn, R. Jameel, L. Abd-Alredha, R. Al-Rubaie y A. Fuad Khudair Aziz. "Preparation of Tannin Based Hydrogel for Biological Application". E-Journal of Chemistry 8, n.º 4 (2011): 1638–43. http://dx.doi.org/10.1155/2011/763295.

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Polymeric blends as potential wound dressing were prepared. Natural polymer (Tannin) and synthetic polymers (PVA and PEG) were used to prepare heterogeneous blends. The product was identified by spectrophotometry. A diaphragm cell was used to measure the diffusion coefficient (D). The result shown the PEG-PVA disk was very faster permeability for all solution. The D of PVA/ PEG-Tannin blend was 0.184x10-3cm2/s higher than Tannin-PEG blend was 0.038x10-3cm2/s. The natural phenolic compounds that can be used artificial membrane to inhibit growth or kill microorganism such as bacteria or fungi.

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Scalon, Silvana de Paula Quintão, Tathiana Elisa Masetto, Daiany Sampaio Carnaúba de Matos y Leandro Motta. "Condicionamento fisiológico e níveis de sombreamento em sementes de barbatimão (Stryphnodendron polyphyllum (Mart.) e S. adstringens (Mart.) Coville)". Revista Árvore 38, n.º 1 (febrero de 2014): 145–53. http://dx.doi.org/10.1590/s0100-67622014000100014.

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A dificuldade técnica devida à ocorrência de dormência das sementes é um entrave para a produção de mudas de espécies nativas em programas de recomposição de áreas degradadas do Cerrado. Objetivou-se com este trabalho avaliar o efeito do condicionamento fisiológico e do sombreamento na qualidade de sementes de duas espécies de barbatimão (Stryphnodendron polyphyllum e S. adstringens). Foram utilizados os seguintes tratamentos pré-germinativos: 1) PEG -1,0 MPa; 2) PEG -1,0 MPa+ KNO3 -1,0 MPa; 3) PEG -0,5 MPa; 4) PEG -0,5 MPa + KNO3 -0,5 MPa; 5) KNO3 -1,0 MPa; 6) Água deionizada; e 7) sementes que não receberam nenhum tratamento pré-germinativo (testemunha). Durante os tratamentos pré-germinativos, as sementes permaneceram incubadas em B.O.D. regulada na alternância de 20/30 ºC, durante 24 h, e em seguida semeadas em bandejas de células com Plantmax® mantidas em quatro níveis de sombreamento (pleno sol, 30%, 50% e 70%) com quatro repetições de 20 sementes. O condicionamento fisiológico com água de sementes de S. polyphyllum e S. adstringens e posterior semeadura em ambiente sombreado de 50 a 70% são eficientes para obter emergência rápida e elevada, maior altura e massa seca das plântulas. As sementes de S. polyphyllum podem ser osmocondicionadas com PEG 1,0 e PEG -0,5 MPA se a semeadura for realizada sob 30% de sombra. Entretanto, a semeadura de S. polyphyllum e S. adstringens não deve ser realizada a pleno sol.

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Zhang, Cheng, Yue Lin, Yuewu Zhu, Zhi Zhang y Jin Liu. "Improved lithium-ion and electrically conductive sulfur cathode for all-solid-state lithium–sulfur batteries". RSC Advances 7, n.º 31 (2017): 19231–36. http://dx.doi.org/10.1039/c7ra02174g.

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Walsh, Scott, Anjali Shah y James Mond. "Improved Pharmacokinetics and Reduced Antibody Reactivity of Lysostaphin Conjugated to Polyethylene Glycol". Antimicrobial Agents and Chemotherapy 47, n.º 2 (febrero de 2003): 554–58. http://dx.doi.org/10.1128/aac.47.2.554-558.2003.

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ABSTRACT Lysostaphin is a 27-kDa endopeptidase that enzymatically disrupts the cell wall of Staphylococcus aureus and is a promising candidate for treating S. aureus blood-borne infections. It would be extremely useful to define conditions that would both increase lysostaphin's in vivo half-life to allow for more effective tissue distribution and reduce its immunogenicity. Conjugation of polyethylene glycol (PEG) to lysostaphin (PEGylation) was investigated as a means to accomplish these goals. Rather than using linear forms of PEG, branched PEGs were chosen as the initial candidates because their large spatial volumes prevent entry of the polymer into the enzyme's active sites, which could potentially reduce enzymatic function. Enzymatic activity for most PEGylated lysostaphins was reduced, but these compounds were still considerably active compared to unconjugated lysostaphin, with conjugates that had lower degrees of PEG modification having greater activity than those with higher degrees. PEGylated lysostaphin injected intravenously had a serum drug half-life of up to 24 h and resulted in much higher plasma drug concentrations than an equal dose of unconjugated lysostaphin, which had a half-life of less than 1 h. Finally, reduced binding affinity was shown for PEGylated lysostaphin in an antilysostaphin capture enzyme-linked immunosorbent assay, with some PEG-lysostaphin conjugates having binding affinities that were reduced more than 10-fold compared to unconjugated lysostaphin. These findings demonstrate that PEGylation of lysostaphin, while diminishing its S. aureus killing activity, results in prolonged serum drug persistence and reduced antibody binding. These features should significantly enhance lysostaphin's therapeutic value as an intravenous “antibiotic” against S. aureus.

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Prlja, Andrej. "Zatična artrodeza interfalangealnih sklepov prstov na stopalih". Slovenian Medical Journal 88, n.º 7-8 (5 de octubre de 2019): 317–26. http://dx.doi.org/10.6016/zdravvestn.2815.

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Izhodišče: Deformacije prstov nog, zlasti pri bolnicah, niso redka težava. Operiramo jih lahko v sklopu obsežnejših korekcij stopala ali kot samostojni poseg. Poznamo vrsto tehnik za zatrditev interfalangealnih sklepov. V prispevku opisujemo zatično (angl. peg-in-socket) tehniko in svoje izkušnje z njo.Metode: Primerjali smo zaplete med skupino 20 bolnikov (26 prstov), operiranih s tehniko zatrditve s Kirschnerjevo iglo (skupina KI), s skupino 50 bolnikov (61 prstov), operiranih s tehniko zatiča (skupina PEG). Razlike v pogostosti zapletov med skupinama KI in PEG smo primerjali s testom deleža (hi-kvadrat).Znotraj same skupine PEG smo izboljšave glede bolečine in omejitev aktivnosti ocenili s testom razlike dveh aritmetičnih sredin (Z-test). Opisali smo tudi težave z obutvijo, uspešnost zatrditve, morebitne ponovitve bolečih otiščancev na operiranih prstih ter obliko in položaj prstov pred in po posegu.Rezultati: Zgodnji zapleti so bili pogostejši v skupini KI kot v skupini PEG (p < 0,05).V sami skupini PEG se je bolečina po posegu izboljšala s 15,6 na 31,2 (p < 0,01), omejitve aktivnosti s 3,7 na 5,9, (p < 0,01). Tudi po zdravljenju so vsi bolniki še naprej uporabljali udobno ali ortopedsko obutev. Pri 5 od 50 bolnikov smo zatrditve ocenili kot neuspešne: 1 psevdoartroza, 2 rentgenski nezraščanji (angl. non union), 2 nepravilni zraščanji (angl. malunion). Pred operacijo so imeli vsi bolniki deformirane prste z bolečimi otiščanci. Po posegu je bilo 9 bolnikov brez otiščancev in bolečin, ostali pa so še navajali občasne manjše bolečine. Položaj in obliko prstov po posegu smo 9-krat ocenili kot odlične, 50-krat kot dobre in 2-krat kot slabe.Zaključek: Zatična zatrditev malih sklepov prstov stopal je nekoliko zahtevnejša tehnika, ki pa omogoča predvidljive in ponovljive rezultate z uporabo bolnikovih tkiv in brez tujkov. Izvaja se lahko ambulantno in ni draga.

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Li, Jamma, Christopher Weir, Richard Fulton y Suran L. Fernando. "Skin Testing and Basophil Activation Testing Is Useful for Assessing Immediate Reactions to Polyethylene Glycol-Containing Vaccines". Vaccines 11, n.º 2 (23 de enero de 2023): 252. http://dx.doi.org/10.3390/vaccines11020252.

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Background: The mechanism of immediate reactions to drugs or vaccines containing polyethylene glycol (PEG) and PEG derivatives is not fully elucidated. It is considered in many instances to be IgE-mediated. Diagnosis and management of PEG allergy is topical, as BNT162b and mRNA-1273 contain PEG (2[PEG-2000]-N), and ChAdOx1-S and NVX-CoV2373 contain polysorbate 80. mRNA vaccines contain PEG 2000, which encapsulates the mRNA to impair its degradation. This PEG MW is specific to mRNA vaccines and is not used in other drugs and vaccines. PEG 2000 allergy is not well studied, as higher PEG molecular weights are implicated in most of the PEG allergy published in the literature. Methods: We performed a literature review on PEG allergy and sought to evaluate the safety and effectiveness of our protocol for assessment of PEG 2000 and polysorbate 80 reactions in an outpatient clinic setting. All patients referred to our drug allergy service between 1 July 2021 and 31 December 2021 with suspected immediate allergy to PEG or its derivatives were eligible for the study. Skin testing (ST) and basophil activation testing (BAT) were performed for all patients to multiple PEG molecular weights (MWs). Results: We reviewed twenty patients during the study period. Five patients were allergic. Fifteen patients had a masquerade of allergy and were enrolled as control patients. PEG 2000, polysorbate 80, BNT162b, and ChAdOx1-S had excellent performance characteristics on skin testing. BAT showed high specificity for all vaccines and PEG MWs. Discussion: In our small study, we found ST and BAT to add useful information, particularly for PEG 2000 allergy. Further study of our protocol in larger patient cohorts will provide more information on its performance characteristics and usefulness.

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Swar, Sumita, Veronika Máková y Ivan Stibor. "The Covalent Tethering of Poly(ethylene glycol) to Nylon 6 Surface via N,N′-Disuccinimidyl Carbonate Conjugation: A New Approach in the Fight against Pathogenic Bacteria". Polymers 12, n.º 10 (24 de septiembre de 2020): 2181. http://dx.doi.org/10.3390/polym12102181.

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Different forms of unmodified and modified Poly(ethylene glycols) (PEGs) are widely used as antifouling and antibacterial agents for biomedical industries and Nylon 6 is one of the polymers used for biomedical textiles. Our recent study focused on an efficient approach to PEG immobilization on a reduced Nylon 6 surface via N,N′–disuccinimidyl carbonate (DSC) conjugation. The conversion of amide functional groups to secondary amines on the Nylon 6 polymer surface was achieved by the reducing agent borane-tetrahydrofuran (BH3–THF) complex, before binding the PEG. Various techniques, including water contact angle and free surface energy measurements, atomic force microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, and Fourier-transform infrared spectroscopy, were used to confirm the desired surface immobilization. Our findings indicated that PEG may be efficiently tethered to the Nylon 6 surface via DSC, having an enormous future potential for antifouling biomedical materials. The bacterial adhesion performances against S. aureus and P. aeruginosa were examined. In vitro cytocompatibility was successfully tested on pure, reduced, and PEG immobilized samples.

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22

Takahashi, Akihiro, Yuta Ozaki, Akinori Kuzuya y Yuichi Ohya. "Impact of Core-Forming Segment Structure on Drug Loading in Biodegradable Polymeric Micelles Using PEG-b-Poly(lactide-co-depsipeptide) Block Copolymers". BioMed Research International 2014 (2014): 1–10. http://dx.doi.org/10.1155/2014/579212.

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We synthesized series of amphiphilic AB-type block copolymers having systematic variation in the core-forming segments using poly(lactide-co-depsipeptide)s as a hydrophobic segment and prepared polymeric micelles using the block copolymers, PEG-b-poly(lactide-co-depsipeptide). We then discussed the relationship between the core-forming segment structure and drug loading efficiency for the polymeric micelles. PEG-b-poly(lactide-co-depsipeptide)s, PEG-b-PLGL containingl-leucine (Leu), and PEG-b-PLGF containingl-phenylalanine (Phe), with similar molecular weights and various mole fractions of depsipeptide units, were synthesized. Polymeric micelles entrapping model drug (fluorescein, FL) were prepared using these copolymers. As a result, PEG-b-poly(lactide-co-depsipeptide) micelles showed higher drug loading compared with PEG-b-PLLA and PEG-b-PDLLA as controls. The drug loading increased with increase in the mole fraction of depsipeptide unit in the hydrophobic segments. The introduction of aliphatic and aromatic depsipeptide units was effective to achieve higher FL loading into the micelles. PEG-b-PLGL micelle showed higher drug loading than PEG-b-PLGF micelle when the amount of FL in feed was high. These results obtained in this study should be useful for strategic design of polymeric micelle-type drug delivery carrier with high drug loading efficiency.

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23

Pompéia, L. "Chemical Abundances of the S Star GZ Peg". Publications of the Astronomical Society of Australia 26, n.º 3 (2009): 354–58. http://dx.doi.org/10.1071/as08041.

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AbstractThe chemical compositions of stars from the Asymptotic Giant Branch are still poorly known due to the low temperatures of their atmospheres and therefore the presence of many molecular transitions hampering the analysis of atomic lines. One way to overcome this difficulty is by the study of lines in regions free from molecular contamination. We have chosen some of those regions to study the chemical abundance of the S-type star GZ Peg. Stellar parameters are derived from spectroscopic analysis and a metallicity of –0.77 dex is found. Chemical abundances of 9 elements are reported and an enhancement of s-process elements is inferred, typical to that of an S-type star.

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24

Costanza, Frankie, Shruti Padhee, Haifan Wu, Yan Wang, Jesse Revenis, Chuanhai Cao, Qi Li y Jianfeng Cai. "Investigation of antimicrobial PEG-poly(amino acid)s". RSC Adv. 4, n.º 4 (2014): 2089–95. http://dx.doi.org/10.1039/c3ra44324h.

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25

Aso, Ayaka, Hinako Nabetani, Yoshifumi Matsuura, Yuichiro Kadonaga, Yoshifumi Shirakami, Tadashi Watabe, Taku Yoshiya et al. "Evaluation of Astatine-211-Labeled Fibroblast Activation Protein Inhibitor (FAPI): Comparison of Different Linkers with Polyethylene Glycol and Piperazine". International Journal of Molecular Sciences 24, n.º 10 (12 de mayo de 2023): 8701. http://dx.doi.org/10.3390/ijms24108701.

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Fibroblast activation proteins (FAP) are overexpressed in the tumor stroma and have received attention as target molecules for radionuclide therapy. The FAP inhibitor (FAPI) is used as a probe to deliver nuclides to cancer tissues. In this study, we designed and synthesized four novel 211At-FAPI(s) possessing polyethylene glycol (PEG) linkers between the FAP-targeting and 211At-attaching moieties. 211At-FAPI(s) and piperazine (PIP) linker FAPI exhibited distinct FAP selectivity and uptake in FAPII-overexpressing HEK293 cells and the lung cancer cell line A549. The complexity of the PEG linker did not significantly affect selectivity. The efficiencies of both linkers were almost the same. Comparing the two nuclides, 211At was superior to 131I in tumor accumulation. In the mouse model, the antitumor effects of the PEG and PIP linkers were almost the same. Most of the currently synthesized FAPI(s) contain PIP linkers; however, in our study, we found that PEG linkers exhibit equivalent performance. If the PIP linker is inconvenient, a PEG linker is expected to be an alternative.

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26

Sari Rahayu, Murni, Nurhayati ., Radite Tistama y Yenni Asbur. "PEG Based Alternative Stimulants and the Effect on Latex Production and Physiology of 6 Years Old of Clone PB 260". International Journal of Engineering & Technology 7, n.º 4.15 (7 de octubre de 2018): 465. http://dx.doi.org/10.14419/ijet.v7i4.15.25257.

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The objectives of this study is to study formulation of PEG based alternative stimulant to increase latex production and physiologically safe for clones PB 260. This research was conducted at Sungei Putih Research Center, Rubber Research Center, Deli Serdang Regency, Province of North Sumatera and PTPD Paya Pinang, Tebing Tinggi, North Sumatera. The study uses 6 year-old of rubber clone PB 260 to determine differences in some parameter such as production (g/p/s), inorganic phosphate, sucrose and thiol levels. The results showed that stimulants have significant effect on production (g/p/s) and inorganic phosphate. PEG applications can encourage increased production (g/p/s) and inorganic phosphate. The combination of stimulant and PEG has very significant effect on production (g/p/s) and inorganic phosphate.

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27

Zhou, Guohang, Jiexiang Zeng, Song Tang, Zijian Bai, Jianyu Jiang, Hong Zhang y Yan Wang. "One-Step Bulk-Suspension Polymerization of Polyethylene Glycol-Based Copolymer Microspheres for Phase Change Textiles". Polymers 15, n.º 9 (27 de abril de 2023): 2090. http://dx.doi.org/10.3390/polym15092090.

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The paper presents a feasible strategy through one-step bulk-suspension polymerization, grafting PEG onto an in situ synthesized copolymer. In more detail, PEG was grafted onto a homemade polystyrene/maleic anhydride copolymer (SMA) via bulk-suspension polymerization with poly(vinyl alcohol) as a suspending agent. According to the optimal reaction conditions, the grafting rate of PEG was 56.2% through chemical titration experiments. At the same time, the quantitative relationship between the grafting rate and enthalpy was demonstrated for the first time in a PEG-based solid–solid phase change material (S-SPCM). Morphology observation revealed that the obtained S-SPCM is made up of white microspheres of approximately 100–150 μm. The powdery product polystyrene/maleic anhydride grafted polyethylene glycol (SMA-g-PEG) obtained through bulk-suspension polymerization endowed that the whole product could be used directly as a phase change material without postprocessing. The melting enthalpy and crystallization enthalpy of SMA-g-PEG were 79.3 J/g and 76.9 J/g, respectively. Based on the effective fixed load of PEG, the macrostructure of SMA-g-PEG was almost unchanged at 70 °C compared with the macrostructures at 20 °C, and the latent heat of SMA-g-PEG was decreased slightly after 1000 thermal cycles. Overall, the obtained SMA-g-PEG can be used as a filler in insulation materials and composited with fibers to obtain phase change thermoregulated smart textiles.

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Huang, Jian-Yuan, Min-Hua Chen y Feng-Huei Lin. "The Synthesis and Characterization of PEG-SH-Modified Gold Nanoparticle in One-Pot Synthesis by Stenotrophomonas maltophilia". Journal of Nanoscience and Nanotechnology 19, n.º 11 (1 de noviembre de 2019): 7278–84. http://dx.doi.org/10.1166/jnn.2019.16625.

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Colloidal gold nanoparticles have been researched and utilized in many technical applications. However, the conventionalmethods to produce polyethyleneglycol (PEG) immobilized gold nanoparticles have to take several steps, including residual solvent removing. In the study, we propose an idea green route to synthesize gold nanoparticles by using Stenotrophomonas maltophilia in a one-pot reaction. The relationship between Au precursor and S. maltophilia was evaluated systematically. After PEG-SH addition, the bacterial cell wall was broken down and the synthetic nanoparticles could be released into culture medium. Furthermore, we identified that the crystal structure of synthetic gold nanoparticle was face-center cubic and PEG-SH was immobilized on synthetic gold nanoparticle ideally. The size of Au-PEG-SH was smaller than 30 nm. These findings suggest that gold nanoparticle with PEG-SH modification could be prepared in an eco-friendly one-pot reaction through the metabolic activity of S. maltophilia.

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Zheng, Yong Jie, Dan Hui Wang y Jing Zhi Tian. "Preparation and Application of Multiwalled Carbon Nanotubes Microspheres/Poly(ethylene glycol) Coated Fiber for SPME". Advanced Materials Research 512-515 (mayo de 2012): 2084–87. http://dx.doi.org/10.4028/www.scientific.net/amr.512-515.2084.

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In this context,the sol-gel approach to the preparation of solid-phase microextraction fibers is applied for extracting of benzene and mathanol from enviromental water samples.Therefore,two different substances such as PEG and MWCNTs is added to the coating.PEG/MWCNTs fibers are prepared using sol-gel technology as a process.MWCNTs is immobilized as microspheres in the pores of PEG coating using Scanning Electron Microscope(SEM).At last, the results show that PEG/MWCNTs fibers are higher extraction efficiency than PEG fibers. Several factors also are considered and optimized,such as extraction temperature, extraction time,inoic strength,stirring speed,desorption temperature and desorption time.LOD(S/N=5) and LOQ(S/N=10) for sol-gel PEG/MWCNTs fibers for extraction of benzene and methanol is 1µg/L and 2µg/L, linear range is 2-2800µg/mL and 2-3000µg/L, linear correlation coefficient is 0.9937 and 0.9940, the RSDs (RSD, n = 7) is 5.1%. and 6.7%, respectively.

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30

Abdulsada, Farah M., Nehia N. Hussein, Ghassan M. Sulaiman, Amer Al Ali y Muhanad Alhujaily. "Evaluation of the Antibacterial Properties of Iron Oxide, Polyethylene Glycol, and Gentamicin Conjugated Nanoparticles against Some Multidrug-Resistant Bacteria". Journal of Functional Biomaterials 13, n.º 3 (2 de septiembre de 2022): 138. http://dx.doi.org/10.3390/jfb13030138.

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Antibacterial resistance is observed as a public health issue around the world. Every day, new resistance mechanisms appear and spread over the world. For that reason, it is imperative to improve the treatment schemes that have been developed to treat infections caused by wound infections, for instance, Staphylococcus epidermidis (S. epidermidis), Proteus mirabilis (P. mirabilis), and Acinetobacter baumannii (A. baumannii). In this case, we proposed a method that involves mixing the Gentamicin (Gen) with iron oxide nanoparticles (Fe3O4 NPs) and a polymer (polyethylene glycol (PEG)) with Fe3O4 NPs. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), energy dispersive X-ray (EDX), scanning electron microscope (SEM), and transmission electron microscope (TEM) were used to characterize Fe3O4 NPs. Zeta potential and dynamic light scattering (DLS) were also assessed. The antibacterial activity of Fe3O4 NPs, Fe3O4 NPs+PEG, Fe3O4 NPs+Gen, and Fe3O4 NPs+PEG+Gen composites was investigated. The results showed a significant improvement in the antibacterial activity of nanoparticles against bacterial isolates, especially for the Fe3O4 NPs+PEG+Gen as the diameter of the inhibition zone reached 26.33 ± 0.57 mm for A. baumannii, 25.66 ± 0.57 mm for P. mirabilis, and 23.66 ± 0.57 mm for S. epidermidis. The Fe3O4 NPs, Fe3O4 NPs+PEG, Fe3O4+Gen, and Fe3O4+PEG+Gen also showed effectiveness against the biofilm produced by these isolated bacteria. The minimum inhibitory concentration (MIC) of Fe3O4 NPs for S. epidermidis was 25 µg mL−1 and for P. mirabilis and A. baumannii was 50 µg mL−1. The findings suggest that the prepared nanoparticles could be potential therapeutic options for treating wound infections caused by S. epidermidis, P. mirabilis, and A. baumannii.

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31

Molla, Aniruddha, Meenakshi Sahu, Yogendra Kumar y Sahid Hussain. "Soft template mediated synthesis of Bi–In–Zn–S and its efficient visible-light-driven decomposition of methylene blue". RSC Advances 5, n.º 52 (2015): 41941–48. http://dx.doi.org/10.1039/c5ra07248d.

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Bi–In–Zn–S nanostructures were successfully synthesized in PEG-PPG-PEG at various temperatures and are used as recyclable photocatalysts for the degradation of methylene blue under visible light (sunlight and 200 W tungsten lamp).

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32

Kim, Jae Hoon, Jun Sik Son, Kwi Deok Park, Jong Man Kim, Jae Jin Kim, Kwang Duk Ahn y Dong Keun Han. "Blood Compatibility of Novel Zwitterionic PEG-Grafted Nitinol Alloy for Peripheral Arterial Stents". Key Engineering Materials 342-343 (julio de 2007): 805–8. http://dx.doi.org/10.4028/www.scientific.net/kem.342-343.805.

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In this study, newly synthesized zwitterionic PEG was grafted on Nitinol alloy using oxidation treatment. The surface property and blood compatibility of surface-modified Nitinols were examined. The results of surface analysis showed that the contact angle and the ratio of oxygen to carbon significantly decreased with Nitinol alloys. The total amount of fibrinogen (0.095 μg/cm2) adsorbed onto TiNi-PEG2K-N+-S- was lower than that of TiNi control (0.12 μg/cm2). The platelet adhesion decreased in the order of TiNi control > TiNi-MPEG2K > TiNi-PEG2K-N+-S. Particularly, zwitterionic PEG with PEG2K was proven better than any others. The results indicated that zwitterionic PEG surface could significantly suppress platelet adhesion and protein adsorption as compared to other samples. The present study suggested that grafted zwitterionic PEG structure may possess improved blood compatibility.

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Fabry, Mary E., Seetharama A. Acharya, Fantao Meng, Sandra M. Suzuka y Dhananjay K. Kaul. "The Supra Perfusion Agent PEGylated Albumin and Its Tempol Derivative Improve Blood Oxygenation and Ameliorate Inflammatory Response in Sickle Transgenic Mice". Blood 118, n.º 21 (18 de noviembre de 2011): 2117. http://dx.doi.org/10.1182/blood.v118.21.2117.2117.

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Abstract Abstract 2117 Sickle cell disease (SCD) is characterized by episodes of vaso-occlusive crisis and chronic inflammation. At present, there is no FDA-approved plasma expander with antioxidant properties for the management of acute vaso-occlusive episodes in SCD. We propose a strategy involving a supra perfusion fluid or a combination of a supra perfusion fluid incorporating an antioxidant that will alleviate oxidative stress and vaso-occlusive complications in SCD. HexaPEGylated albumin (P5K6-Alb or PEG-Alb) was generated by extension arm facilitated (EAF) PEGylation using PEG-5K maleimide. PEG-Alb-T12 was prepared using EAF chemistry with 12 Tempol molecules. Sickle (S+S-Antilles) mice were top-loaded with either 4% PEG-Alb or PEG-Alb-T12 at 10% of mouse blood volume. We used sickle mice and BOLD (Blood Oxygen Level Dependent) MRI imaging of the brain to visualize changes in blood oxygenation. In another series of experiments sickle mice were subjected to 16 hr of hypoxia (8% O2, 0.5% CO2, balance N2) followed by 4 hr of re-oxygenation at ambient air; these mice were top-loaded at 10% of mouse blood volume with either 4% PEG-Alb or PEG-Alb-T12 at the onset of re-oxygenation. Both of these compounds are low viscosity fluids following administration of 4% compound at 10% blood volume. Hemodynamic properties were monitored by videomicroscopy of the cremaster. C57BL mice were used as controls. We found that S+S-Antilles mice had elevated levels of deoxyhemoglobin (deoxyHb) in brain as previously reported. Although we hypothesized that anti-oxidant Tempol groups would increase the efficacy of PEG-albumin, we found that either PEG-Alb-T12 or PEG-Alb without Tempol reduced deoxyHb levels to those found in normal C57BL mice. In a separate set of experiments, hypoxia-reoxygenation in sickle mice caused a marked 5-fold increase in leukocyte adhesion and 7.2-fold increase in transendothelial leukocyte emigration (each P<0.0001) that was accompanied by a significant decline in red cell velocity, wall shear rate and volumetric flow (P<0.05–0.023) in the venules of the cremaster muscle microcirculation. We found that top-loading either PEG-Alb-T12 or PEG-Alb without Tempol at the onset of reoxygenation ameliorated leukocyte adhesion and emigration, and markedly improved hemodynamic parameters almost to the control values. In conclusion, in SCD, the presence of deoxyHb increases polymer formation and the risk of vaso-occlusion; both PEG-Alb-T12 and PEG-Alb markedly reduced deoxyHb levels. We have previously demonstrated an inverse correlation between perfusion and deoxyHb levels in these mice (Kennan et al. Mag Res in Med, 2004). These results are consistent on a macroscopic scale with the intravital studies that show increased flow following amelioration of the inflammatory effects of reoxygenation by either PEG-Alb-T12 or PEG-Alb. The observed amelioration of inflammation and increased blood oxygenation may, at least partly, be attributed to the reported tonic release of nitric oxide via increased wall shear stress and mechanotransduction (Tsai et al. 2011), and to oxidant scavenging. Taken together, these studies demonstrate the marked efficacy of both of these agents in reducing inflammation and increasing blood oxygenation and flow, all of which characterize SCD and contribute to its pathology. Disclosures: No relevant conflicts of interest to declare.

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Khoerunnisa, Fitri, Chintia Kulsum, Fitri Dara, Mita Nurhayati, Nisa Nashrah, Siti Fatimah, Amelinda Pratiwi et al. "Toughened chitosan-based composite membranes with antibiofouling and antibacterial properties via incorporation of benzalkonium chloride". RSC Advances 11, n.º 27 (2021): 16814–22. http://dx.doi.org/10.1039/d1ra01830b.

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Chitosan/PEG/MWCNT/BKC membranes exhibit enhanced antibiofouling properties against S. aureus and E. coli. MWCNT/BKC are located as dispersed nano-clusters with π–π stacking interactions in the chitosan matrix, and are coved by PEG chains.

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Wang, Feng, Yan-Hua Liu, Yong Ma, Zheng-Gang Cui y Lin-Lin Shao. "Application of TMA-PEG to promote C-phycocyanin extraction from S. platensis in the PEG ATPS". Process Biochemistry 52 (enero de 2017): 283–94. http://dx.doi.org/10.1016/j.procbio.2016.11.006.

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36

Marito, Shinta, Sunita Keshari y Chun-Ming Huang. "PEG-8 Laurate Fermentation of Staphylococcus epidermidis Reduces the Required Dose of Clindamycin Against Cutibacterium acnes". International Journal of Molecular Sciences 21, n.º 14 (19 de julio de 2020): 5103. http://dx.doi.org/10.3390/ijms21145103.

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The probiotic activity of skin Staphylococcus epidermidis (S. epidermidis) bacteria can elicit diverse biological functions via the fermentation of various carbon sources. Here, we found that polyethylene glycol (PEG)-8 Laurate, a carbon-rich molecule, can selectively induce the fermentation of S. epidermidis, not Cutibacterium acnes (C. acnes), a bacterium associated with acne vulgaris. The PEG-8 Laurate fermentation of S. epidermidis remarkably diminished the growth of C. acnes and the C. acnes-induced production of pro-inflammatory macrophage-inflammatory protein 2 (MIP-2) cytokines in mice. Fermentation media enhanced the anti-C. acnes activity of a low dose (0.1%) clindamycin, a prescription antibiotic commonly used to treat acne vulgaris, in terms of the suppression of C. acnes colonization and MIP-2 production. Furthermore, PEG-8 Laurate fermentation of S. epidermidis boosted the activity of 0.1% clindamycin to reduce the sizes of C. acnes colonies. Our results demonstrated, for the first time, that the PEG-8 Laurate fermentation of S. epidermidis displayed the adjuvant effect on promoting the efficacy of low-dose clindamycin against C. acnes. Targeting C. acnes by lowering the required doses of antibiotics may avoid the risk of creating drug-resistant C. acnes and maintain the bacterial homeostasis in the skin microbiome, leading to a novel modality for the antibiotic treatment of acne vulgaris.

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Jobbágy, Ákos, Anikó Rita Marik y Gábor Fazekas. "Quantification of the Upper Extremity Motor Functions of Stroke Patients Using a Smart Nine-Hole Peg Tester". Journal of Healthcare Engineering 2018 (2018): 1–9. http://dx.doi.org/10.1155/2018/7425858.

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This paper introduces a smart nine-hole peg tester (s-9HPT), which comprises a standard nine-hole peg test pegboard, but with light-emitting diodes (LEDs) next to each hole. The s-9HPT still supports the traditional nine-hole peg test operating mode, in which the order of the peg placement and removal can be freely chosen. Considering this, the s-9HPT was used in lab research to analyze the traditional procedure and possible new procedures. As this analysis required subjects with similar levels of dexterity, measurement data from 16 healthy subjects (seven females, nine males, 25–80 years old) were used. We consequently found that illuminating the LEDs in various patterns facilitated guided tests of diverse complexity levels. Next, to demonstrate the clinical application of the s-9HPT, the improvement in the hand dexterity of 12 hospitalized stroke patients (45–80 years old, six females and six males) was monitored during their rehabilitation. Here, we used traditional and guided tests validated by healthy subjects. Consequently, improvements were found to be patient specific. At the beginning of rehabilitation, traditional tests suitably indicate improvements, while guided tests are beneficial following improvements in motor functions. Further, the guided tests motivated certain patients, meaning the rehabilitation was more effective for these individuals.

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Zara, Nena. "POLYETHYLENE GLYCOL 8000 (PEG 8000): POTENTIAL DUST SUPPRESSANT TO SANDY LOAM PRESENT IN CONSTRUCTION AND MININGSITES". BIMP-EAGA Journal for Sustainable Tourism Development 4, n.º 1 (6 de junio de 2015): 119–30. http://dx.doi.org/10.51200/bimpeagajtsd.v4i1.3122.

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Constant exposure to dusts generated from construction and mining sites as well as from farming activities poses danger to one‟s health. A possible treatment to sandy loam to address this concern is the Polyethylene Glycol (PEG) 8000 which has been utilized as an adhesive for industrial purposes. This study therefore attempts to uncover PEG‟s potential as a dust suppressant to sandy loam soil to minimize dusts‟ negative effects. The soil‟s cohesion disclosed from the direct shear test served as a basis in selecting the best combination whereby 5%, 12.5% and 20% concentrations of PEG 8000 solution were added to soil at 15% by weight of sandy loam. The water as binding material to sandy loam served as the control to check the effectiveness of treatment. The dust control test applied the cohesion revealed in the direct shear test, which was at 12.5% without compromising the shear strength. The loss in dry mass of sandy loam after exposure to air action was compared to control. The results showed 2.90% and 0.15% loss in dry mass for control and PEG 8000 respectively, indicate that the treatment utilized is effective.

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Wang, Bochu, Yang Cao, Shaoping Chi y Deshuai Lou. "A PEGylation Technology of L-Asparaginase with Monomethoxy Polyethylene Glycol-Propionaldehyde". Zeitschrift für Naturforschung C 67, n.º 5-6 (1 de junio de 2012): 312–18. http://dx.doi.org/10.1515/znc-2012-5-611.

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Polyethylene glycol (PEG) conjugation technology has been successfully applied to improve the performance of protein drugs. In this study, L-asparaginase was N-terminal sitespecifically modified by alkylating PEG with monomethoxy polyethylene glycol-propionaldehyde (mPEG-ALD20000). The optimum reaction parameters were determined as pH 5.0, a molar ratio of mPEG-ALD20000 to L-asparaginase of 10:1, a reaction time of 16 h and temperature of 25 °C. PEG-L-asparaginase (PEG-L-ASNase) was isolated and purified with consecutive anion-exchange (XK, 16 × 20 cm, Q Sepharose FF) and gel-filtration (Tricorn, 10 × 600 cm, Sephacryl S-300 HR) chromatography, respectively. PEG-L-ASNase retained 43.5% of its activity and the N-terminal amino groups were modified to an extent of 3.67%

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40

Solanki, Shailendra Singh, Love Kumar Soni y Rajesh Kumar Maheshwari. "Study on Mixed Solvency Concept in Formulation Development of Aqueous Injection of Poorly Water Soluble Drug". Journal of Pharmaceutics 2013 (28 de marzo de 2013): 1–8. http://dx.doi.org/10.1155/2013/678132.

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In the present investigation, mixed-solvency approach has been applied for the enhancement of aqueous solubility of a poorly water- soluble drug, zaltoprofen (selected as a model drug), by making blends (keeping total concentrations 40% w/v, constant) of selected water-soluble substances from among the hydrotropes (urea, sodium benzoate, sodium citrate, nicotinamide); water-soluble solids (PEG-4000, PEG-6000); and co-solvents (propylene glycol, glycerine, PEG-200, PEG-400, PEG-600). Aqueous solubility of drug in case of selected blends (12 blends) ranged from 9.091 ± 0.011 mg/ml–43.055 ± 0.14 mg/ml (as compared to the solubility in distilled water 0.072 ± 0.012 mg/ml). The enhancement in the solubility of drug in a mixed solvent containing 10% sodium citrate, 5% sodium benzoate and 25 % S cosolvent (25% S cosolvent contains PEG200, PEG 400, PEG600, Glycerine and Propylene glycol) was more than 600 fold. This proved a synergistic enhancement in solubility of a poorly water-soluble drug due to mixed cosolvent effect. Each solubilized product was characterized by ultraviolet and infrared techniques. Various properties of solution such as pH, viscosity, specific gravity and surface tension were studied. The developed formulation was studied for physical and chemical stability. This mixed solvency shall prove definitely a boon for pharmaceutical industries for the development of dosage form of poorly water soluble drugs.

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Shao, Mei Ling, Qing Yang y Lu Chen. "Compatibility and Crystallinity of Electrospun Aligned PHBV/PEG Ultrafine Fibers Scaffolds". Advanced Materials Research 668 (marzo de 2013): 85–90. http://dx.doi.org/10.4028/www.scientific.net/amr.668.85.

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Aligned PHBV/PEG ultrafine fibers are fabricated for potential applications in tissue repair. In this paper we find that the optimum spinning parameters to prepare aligned PHBV/PEG fibers is as follows: the concentration of 8wt%, voltage at 10kv, receiving distance at 18cm, the boost speed at 0.8ml/h and the best linear velocity of the rotating drum at 9.5m/s. The content of PEG is less than 50%. In addition, we investigate the interaction between PHBV and PEG in its entirety; we also discuss the surface morphology of the blends, compatibility, thermal decomposition and crystallization behavior by the help of different test methods.

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Somyoonsap, Peechapack, Akio Tani, Jittima Charoenpanich, Toshiyuki Minami, Kazuhide Kimbara y Fusako Kawai. "Involvement of PEG-carboxylate dehydrogenase and glutathione S-transferase in PEG metabolism by Sphingopyxis macrogoltabida strain 103". Applied Microbiology and Biotechnology 81, n.º 3 (diciembre de 2008): 473–84. http://dx.doi.org/10.1007/s00253-008-1635-7.

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43

Kurowska, Monika, Vania Widyaya, Ali Al-Ahmad y Karen Lienkamp. "Surface-Attached Poly(oxanorbornene) Hydrogels with Antimicrobial and Protein-Repellent Moieties: The Quest for Simultaneous Dual Activity". Materials 11, n.º 8 (11 de agosto de 2018): 1411. http://dx.doi.org/10.3390/ma11081411.

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By copolymerizing an amphiphilic oxanorbornene monomer bearing N- tert-butyloxycarbonyl (Boc) protected cationic groups with an oxanorbornene-functionalized poly(ethylene glycol) (PEG) macromonomer, bifunctional comb copolymers were obtained. Varying the comonomer ratios led to copolymers with PEG contents between 5–25 mol %. These polymers were simultaneously surface-immobilized on benzophenone-bearing substrates and cross-linked with pentaerythritoltetrakis(3-mercaptopropionate). They were then immersed into HCl to remove the Boc groups. The thus obtained surface-attached polymer hydrogels (called SMAMP*-co-PEG) were simultaneously antimicrobial and protein-repellent. Physical characterization data showed that the substrates used were homogeneously covered with the SMAMP*-co-PEG polymer, and that the PEG moieties tended to segregate to the polymer–air interface. Thus, with increasing PEG content, the interface became increasingly hydrophilic and protein-repellent, as demonstrated by a protein adhesion assay. With 25 mol % PEG, near-quantitative protein-adhesion was observed. The antimicrobial activity of the SMAMP*-co-PEG polymers originates from the electrostatic interaction of the cationic groups with the negatively charged cell envelope of the bacteria. However, the SMAMP*-co-PEG surfaces were only fully active against E. coli, while their activity against S. aureus was already compromised by as little as 5 mol % (18.8 mass %) PEG. The long PEG chains seem to prevent the close interaction of bacteria with the surface, and also might reduce the surface charge density.

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44

Şenel, Mehmet, Metin Tülü y Ayhan Bozkurt. "Synthesis and proton conductivity of anhydrous dendritic electrolytes". Open Chemistry 5, n.º 2 (1 de junio de 2007): 546–56. http://dx.doi.org/10.2478/s11532-007-0016-x.

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AbstractWater soluble PEG cored dendritic hexa-acid which comprises peripheral carboxylic acidic groups were prepared via nucleophilic substitution reactions. Novel anhydrous proton conducting electrolytes were prepared by incorporation of the heterocyclic protogenic solvent imidazole (Im) into PEG cored dendritic hexa acid, (PEG-HA), at several molar ratios of Im to-COOH units of PEG-HA. The complexation of PEG-HA and Im was illustrated by infrared spectroscopy (FT-IR). The materials are thermally stable up to 150 °C as evidenced by thermogravimetry analysis (TGA). Differential scanning calorimetry (DSC) results verified that the organic electrolytes are homogeneous and amorphous. The proton conductivities were characterized by means of AC impedance spectroscopy and a maximum conductivity of 1 × 10−3 S/cm was measured at 120 °C in the anhydrous state.

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45

Qiao, H., B. S. Dalay y J. A. G. Knight. "Robotic Assembly Operation Strategy Investigation Without Force Sensors Through the Research on Contact Point Location and Range of Peg Movement". Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 210, n.º 5 (octubre de 1996): 471–85. http://dx.doi.org/10.1243/pime_proc_1996_210_144_02.

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The assembly operation plays an important role in manufacturing industry. The robotic peg-hole insertion operation, the most widely used assembly model, has been heavily studied due to its widespread application. The purpose of the research in this area is to design techniques that enable the robot to perform assembly operations with high speed, high accuracy and low cost. The key problems of strategy investigation research include: (a) designing a series of sub-goals through which the peg-hole system can achieve the insertion operation from any point in the initial area, (b) calculating the allowable range for the initial area, (c) determining the values and duration of the control inputs and (d) analysing the robustness of the strategy. There are many strategies given to perform the assembly operation with the assistance of specially designed force sensors or flexible wrists. In this paper: 1. The map from the position of the peg in the coordinate frame attached to the hole and the location of the contact point in the frame attached to the peg was analysed. This provided the basis for the identification of the position relationship between the peg and the hole using a force sensor signal. 2. The range of peg movement was analysed and found to be useful in the selection of the sub-goals for the insertion operation. 3. A deficient and yet precise hardware strategy, characterized by not requiring force sensors or flexible wrists, was analysed. 4. The validity of the deficient hardware strategy was demonstrated through experiments with the UMI-RTX robot. The results were further confirmed through simulation. The allowed initial area, the control input design and the robustness of the strategy were analysed in detail. A constant cycle time of 2.5 s was achieved during the ten trials in which the diameters of the pegs were selected from a choice of 29.99, 31.98 or 31.99 mm with a clearance between the hole remaining at 0.02 mm and a common peg legnth of 41 mm.

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46

Goyal, Kritika, Arpita Konar, B. S. Hemanth Kumar y Veena Koul. "Lactoferrin-conjugated pH and redox-sensitive polymersomes based on PEG-S-S-PLA-PCL-OH boost delivery of bacosides to the brain". Nanoscale 10, n.º 37 (2018): 17781–98. http://dx.doi.org/10.1039/c8nr03828g.

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In the present study, engineered lactoferrin (Lf)-conjugated pH and redox-sensitive polymersomes derived from the triblock copolymer polyethylene glycol-S-S-polylactic acid-polycaprolactone (PEG-S-S-PLA-PCL-OH) have been used to deliver bacosides to the brain.

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47

Silva, Mário R. P. da, Robert S. Matos, Michael D. S. Monteiro, Samuel B. Santos, Henrique D. F. Filho, George R. S. Andrade, Marco Salerno y Luís E. Almeida. "Exploiting the Physicochemical and Antimicrobial Properties of PHB/PEG and PHB/PEG/ALG-e Blends Loaded with Ag Nanoparticles". Materials 15, n.º 21 (27 de octubre de 2022): 7544. http://dx.doi.org/10.3390/ma15217544.

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Poly(3-hydroxybutyrate) (PHB)-based films containing Poly(ethylene glycol) (PEG), esterified sodium alginate (ALG-e) and polymeric additives loaded with Ag nanoparticles (AgNPs) were obtained by a conventional casting method. AgNPs were produced in aqueous suspension and added to polymeric gels using a phase exchange technique. Composite formation was confirmed by finding the Ag peak in the XRD pattern of PHB. The morphological analysis showed that the inclusion of PEG polymer caused the occurrence of pores over the film surface, which were overshadowed by the addition of ALG-e polymer. The PHB functional groups were dominating the FTIR spectrum, whose bands associated with the crystalline and amorphous regions increased after the addition of PEG and ALG-e polymers. Thermal analysis of the films revealed a decrease in the degradation temperature of PHB containing PEG/AgNPs and PEG/ALG-e/AgNPs, suggesting a catalytic effect. The PHB/PEG/ALG-e/AgNPs film combined the best properties of water vapor permeability and hydrophilicity of the different polymers used. All samples showed good antimicrobial activity in vitro, with the greater inhibitory halo observed for the PEG/PEG/AgNPs against Gram positive S. aureus microorganisms. Thus, the PHB/PEG/ALG-e/AgNPs composite demonstrated here is a promising candidate for skin wound healing treatment.

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Fatima .S. Jalli1, Noora Jassim Mohmmed y Tariq J. Alwan. "تحضير ودراسة خصائص اغشية PEG/Zn(ext)2 الرقيقة المحضرة بطريقة الطلاء البرمي". journal of the college of basic education 28, n.º 114 (7 de abril de 2022): 454–62. http://dx.doi.org/10.35950/cbej.v28i114.5434.

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تم تحضير اغشية PEG/Zn(ext)2 عند ( (x=0, 0.02, 0.04, 0.06) بطريقة الطلاء البرمي تم استقصاء تاثير التطعيم بمعقد الزنك على اغشية PEG/Zn(ext)2الرقيقة باستخدام جهاز حيود الاشعة السينية (XRD) ,مجهر القوى الذري (AFM) والتوصيلية الكهربائية المستمرة . فحوصات الـ FT-IR كانت ضروري للتعرف على المجاميع الفعالة في العينات المحضرة ، وكذلك للكشف عن التشويب الذي اجري على هذه العينات . بينت دراسة التوصيلة الكهربائية المستمرة ان قيم التوصيلية للاغشية زادت (1.33x10-7 S/cm) الى ( 3.42x10-9 S/cm ) بزيادة تركيز .Zn (ext)2

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WHITTEMBURY, GUILLERMO, ANGELA C. BIONDI, AZAEL PAZ-ALIAGA, HENRY LINARES, VALENTÍN PARTHE y NANCY LINARES. "Transcellular and Paracellular Flow of Water During Secretion in the Upper Segment of the Malpighian Tubule of Rhodnius Prolixus: Solvent Drag of Molecules of Graded Size". Journal of Experimental Biology 123, n.º 1 (1 de julio de 1986): 71–92. http://dx.doi.org/10.1242/jeb.123.1.71.

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The following molecules graded in size were added to the fluid bathing the blind end of the upper segment of the Malpighian tubules of Rhodnius: urea (U), erythritol (E), mannitol (M), L-glucose (G), sucrose (S), polyethyleneglycol 800 (PEG), raffinose (R), inulin (I) and dextran 15000–18000 (D). U, E, M and G distribute themselves within the cell and the extracellular space, while S, PEG, R, I and D are exclusively extracellular. In addition, the net secretory flow (Jnm8) of these probes was studied as a function of the net secretory volume flow (Jv). Jn8, is made up of a diffusive component (Jd8), mainly due to unstirred layer effects, and of a convective component (Jc8), due to the drag (entrainment) of the probes by the water flow. The relative contribution of Jd8 and of Jc8 for each probe was studied as a function of Jv. It was found that Jc8 >> Jd8 for U, E, M, G, S and PEG. Therefore these probes are dragged by water. On the other hand Jd8 = Jn8 for R, I and D, which are not entrained. It is concluded that water flows via extracellular pathways since S and PEG, which are true extracellular probes, are entrained by solvent. In addition to extracellular pathways, it is suggested that the transcellular structures described by Wessing (1965) and Bergeron et al. (1985) could also be the sites of solute-solvent coupling

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Yu, Chun y Joachim Kohn. "Tyrosine–PEG-derived poly(ether carbonate)s as new biomaterials". Biomaterials 20, n.º 3 (febrero de 1999): 253–64. http://dx.doi.org/10.1016/s0142-9612(98)00169-0.

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