| 1. |
- Steneberg, Pär, et al.
(författare)
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PAN-AMPK activator O304 improves glucose homeostasis and microvascular perfusion in mice and type 2 diabetes patients
- 2018
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Ingår i: JCI INSIGHT. - : American Society for Clinical Investigation. - 2379-3708. ; 3:12
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Tidskriftsartikel (refereegranskat)abstract
- AMPK activated protein kinase (AMPK), a master regulator of energy homeostasis, is activated in response to an energy shortage imposed by physical activity and caloric restriction. We here report on the identification of PAN-AMPK activator O304, which - in diet-induced obese mice - increased glucose uptake in skeletal muscle, reduced beta cell stress, and promoted beta cell rest. Accordingly, O304 reduced fasting plasma glucose levels and homeostasis model assessment of insulin resistance (HOMA-IR) in a proof-of-concept phase IIa clinical trial in type 2 diabetes (T2D) patients on Metformin. T2D is associated with devastating micro-and macrovascular complications, and O304 improved peripheral microvascular perfusion and reduced blood pressure both in animals and T2D patients. Moreover, like exercise, O304 activated AMPK in the heart, increased cardiac glucose uptake, reduced cardiac glycogen levels, and improved left ventricular stroke volume in mice, but it did not increase heart weight in mice or rats. Thus, O304 exhibits a great potential as a novel drug to treat T2D and associated cardiovascular complications.
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| 2. |
- Andersson, Lars Gustaf, et al.
(författare)
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Liemannen och filmens magi
- 1995
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Ingår i: Den magiska lyktan: Magi - teknik. Filmen 100 år. - 9185446165 ; , s. 18-20
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Bokkapitel (populärvet., debatt m.m.)
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| 3. |
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Barnstugan
- 2015
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- Boken är en del av projektet Barnstugan. Boken redogör för en konstnärlig undersökning av två arkitektoniska projekt från slutet av 60-talet. Husen är ett typdaghemsprojekt för Stockholm stad samt Ingmar Bergmans bostad på Fårö. Husen sammanlänkas av det kontor (Abramsons arkitektkontor) som under samma tid projekterade husen. Genom att se på liknelser och skillnader, fysiska och innehållsliga, vill undersöks relationen mellan kollektiv och individ. Till boken har ett antal personer bjudits in att reflektera kring de tematiker projektet tangerar.
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| 4. |
- Janson, Martin, et al.
(författare)
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Analysis of patient selection and external validity in the Swedish contribution to the COLOR trial.
- 2009
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Ingår i: Surgical endoscopy. - : Springer Science and Business Media LLC. - 1432-2218 .- 0930-2794. ; 23:8, s. 1764-9
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: The colon cancer laparoscopic or open resection (COLOR) trial is an international, randomised controlled trial comparing outcomes of open and laparoscopic surgery for colon cancer. The main purpose of this study was to determine representability by comparing included and nonincluded patients in the participating Swedish centres. DESIGN: At eight centres, which included 391 of the 422 Swedish patients, a local database search was performed to identify retrospectively all patients (n = 2,384) who underwent surgery for colon cancer during the inclusion period, and data was retrieved from medical records. RESULTS: Four hundred fifty-six patients were randomised, 65 of whom were excluded post randomisation (group 2), leaving 391 patients in the study (group 1). For 1,566 patients, valid exclusion criteria were found (group 3). Thus, 362 patients were eligible but not included (group 4). Relative to group 1, patients in group 4 had a significantly higher American Society of Anaesthesiologists (ASA) score, more advanced tumour stage and difference regarding the resections performed. Results showed that 1470 patients (62%) could be calculated as feasible for laparoscopic colon resection (LCR) in a clinical, nontrial situation. CONCLUSIONS: The study population in the Swedish part of the COLOR trial was representative of the eligible population with the exception of comorbidity, where those actually included had less severe comorbidity than the nonincluded but eligible patients. In Sweden, 50-60% of colon cancer patients can be operated on by laparoscopy.
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| 5. |
- Jansson, Zheng, 1985-
(författare)
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Characterization of Spruce Xylan and Its Potential for Strength Improvement
- 2013
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Xylan dissolved during kraft cooking and later redeposited on fibre surfaces has been shown to give higher pulp yield and better strength properties. This is economically interesting from an industrial point of view. Many studies have been done to investigate xylan behaviour during kraft cooking, to discover the xylan-cellulose attachment mechanism, to find the optimal xylan retention or adsorption process, and to discover relations between xylan structure and strength enhancement. Most of them have concentrated on hardwood xylan. However, softwoods are the major raw materials for the pulp industries in the northern hemisphere. Earlier studies have shown that the xylan characteristics, rather than simply the amount of xylan, influence the strength-enhancing effect of xylan. To obtain optimal utilization of spruce xylan as a strength enhancer, it is essential to know what the beneficial xylan characteristics are and how cooking conditions affect the characteristics.In this study, kraft cooking of spruce chips was performed under varied cooking conditions and the xylan in the black liquor was precipitated and characterized. It was found that dissolved spruce xylan had a much higher amount of bound lignin compared to previous studies on xylan dissolved from hardwoods. Increased cooking temperature increased the dissolution rate of xylan. The lower alkali charge and higher ionic strength of the cooking liquor resulted in a lower amount of dissolved xylan. Apart from the effect of the amount, cooking conditions also affected substitution of dissolved xylan. Higher temperature and higher ionic strength led to a lower amount of MeGlcA, while the MeGlcA amount of dissolved xylan was preserved during lower alkali cooking.By distinguishing how different cooking conditions affect the characteristics of the xylan dissolved in the black liquor, xylans with different structures were designed to study their effects on pulp strength, that is, the addition of black liquors with certain known xylan characteristics in the kraft cooking process. It was found that the best effect of xylan on tensile strength occurred when the xylan penetrated some distance into the subsurface of the fibre wall. Both low molecular weight and high degree of substitution lowered the tendency of xylan to aggregate, which enabled the dissolved xylan to penetrate some distance into the exposed fibre surface. Upon beating, this xylan was exposed, thus facilitating improvement of fibre-fibre joint formation, which led to increased tensile strength.
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| 6. |
- Kärnebro, Katarina, 1975-
(författare)
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Plugga stenhårt eller vara rolig? : Normer om språk, kön och skolarbete i identitetsskapande språkpraktiker på fordonsprogrammet
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The purpose of this study is to explore the relationship between language, identity construction and learning in the context of the Vehicle programme, a vocational program in Swedish upper secondary schools. The study focuses on language practices and the norms of language, gender and school work that are negotiated in conversations between pupils and between pupils and teachers. The language practices are considered as talk-in-interaction, and identity construction and learning are understood as processes in socially situated activities. The Vehicle programme has its basis in mechanics with links to the vehicle and transport trades, and can be identified as a male-coded program in several respects. The pupils participating in this study were both boys and girls attending a school situated in the North of Sweden. The study was conducted through an ethnographic approach, employing plural methods including observation, field notes, audio-recordings of conversations, and interviews with pupils in focus groups and individually. Recorded conversations were analysed using tools from conversation analysis. The analysis is based on Judith Butler’s theory of gender as performance, Raewyn Connell’s theory of hegemonic masculinity, and Penelope Eckert’s theory of the heterosexual market. A socio-cultural theory of learning describing communities of practice, by Lave and Wenger, which has also been applied to linguistics by Eckert and McConnell-Ginet, forms the basis of the theoretical framework.The analyses of conversations show that the language practices were confrontational, direct and humorous; characteristics that have strong connections to notions of a masculine conversational style. The pupils were not as aware of interactional patterns as they were of the words they used. Thereby the norms in the community of practice, which were based on notions of masculinity and heterosexuality, were not noticed, and worked as undercurrents in the interaction. The girls participated in the language practices in the same ways as the boys, but contrary to the boys, the girls interpreted the language practices as effects of other things than gender, for example as signs of being independent or daring. They also experienced that adjusting to the expectations of normative middle-class femininity was more oppressive than adjusting to the norms that were negotiated within the community of practice. The conversation analyses also show some of the complexity in teachers’ work and their role as mediators of norms and values. Peer reactions to individual pupil turns in the classroom conversations were of more importance for the development of the conversations than teacher responses. Thus there was usually a homogenization of the expressed perspectives. Norms of heterosexuality were constantly reconstructed in interaction within the community of practice and they controlled the pupils’ understanding of what was perceived as normal or deviant behaviour. Thereby the pupils constrained each other’s school performances in the core subjects and reconstructed a difference between being theoretical and practical, a process that was partly supported by the school as an institution. Generally, the pupils in the community of practice had to balance their identity constructions in relation to the peer group, teacher expectations, and their own ambitions, for which reason learning turned out to be more than just a process of acquiring knowledge.
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| 7. |
- Margolin, Sara, et al.
(författare)
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A randomised feasibility/phase II study (SBG 2004-1) with dose-dense/tailored epirubicin, cyclophoshamide (EC) followed by docetaxel (T) or fixed dosed dose-dense EC/T versus T, doxorubicin and C (TAC) in node-positive breast cancer.
- 2011
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Ingår i: Acta Oncologica. - : Informa Healthcare. - 0284-186X .- 1651-226X. ; 50:1, s. 35-41
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the study was to evaluate the feasibility of tailored and dose-dense epirubicin and cyclophosphamide followed by docetaxel as adjuvant breast cancer therapy. Material and methods. Patients with node-positive breast cancer received either four cycles of biweekly and tailored EC (epirubicin 38-60-75-90-105-120 mg/m(2), cyclophosphamide 450-600-900-1200 mg/m(2)) followed by four cycles of docetaxel (60-75-85-100 mg/m(2)) (arm A) or the same regimen with fixed doses (E(90)C(600) + 4 → T(75) + 4) (arm B) or docetaxel, doxorubicin and cyclophosphamide (T(75)A(50)C(500)) every three weeks for six cycles (arm C). All patients received G-CSF support and prophylactic ciprofloxacin. Results. One-hundred and twenty-four patients were randomised in the study. In the A, B and C arm, 17% 19% and 3% of the patients had one or more cycles delayed due to side-effects whereas 24%, 5% and 15% experienced a grade 3 infection or febrile neutropenia. After the introduction of an extra week between the EC and T parts in the A and B arms, grade 3 hand-foot-skin reactions were reduced from 5 to 0.2%. Twenty-nine percent (A and B) and 20% (C) of the patients were hospitalised due to side-effects. Discussion. Dose-dense and tailored EC/T can be given with manageable toxicity and is after adjustment presently studied in the phase III Panther trial.
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| 8. |
- Matikas, Alexios, et al.
(författare)
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Long-term safety and survival outcomes from the Scandinavian Breast Group 2004-1 randomized phase II trial of tailored dose-dense adjuvant chemotherapy for early breast cancer
- 2018
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Ingår i: Breast Cancer Research and Treatment. - : SPRINGER. - 0167-6806 .- 1573-7217. ; 168:2, s. 349-355
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Tidskriftsartikel (refereegranskat)abstract
- Although adjuvant polychemotherapy improves outcomes for early breast cancer, the significant variability in terms of pharmacokinetics results in differences in efficacy and both short and long-term toxicities. Retrospective studies support the use of dose tailoring according to the hematologic nadirs. The SBG 2004-1 trial was a randomized feasibility phase II study which assessed tailored dose-dense epirubicin and cyclophosphamide (EC) followed by docetaxel (T) (group A), the same regimen with fixed doses (group B) and the TAC regimen (group C). Women aged 18-65 years, ECOG PS 0-1 with at least one positive axillary lymph node were randomized 1:1:1. The primary endpoint of the study was the safety and feasibility of the treatment. Toxicity was graded according to CTC-AE version 3.0. The design and short-term toxicity have been previously published. Here, we report safety and efficacy data after 10 years of follow-up. A total of 124 patients were included in the study. After a median follow-up of 10.3 years, the probability for 10-year survival was 78.5, 75.1, and 63.4% and for relapse free survival 64.1, 71.0, and 59.5% for groups A, B, and C, respectively. There were no cases of clinically diagnosed cardiotoxicity or hematologic malignancies. No patient was lost to follow-up. In this randomized phase II trial, tailored dose adjuvant chemotherapy was feasible, without an increased risk for long-term adverse events after a median follow-up of 10 years.
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| 9. |
- Pazooki, David, 1958, et al.
(författare)
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Continent cutaneous urinary diversion in patients with spinal cord injury.
- 2006
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Ingår i: Spinal cord : the official journal of the International Medical Society of Paraplegia. - : Springer Science and Business Media LLC. - 1362-4393. ; 44:1, s. 19-23
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Tidskriftsartikel (refereegranskat)abstract
- STUDY DESIGN: Retrospective study. OBJECTIVE: To examine the functional results and effect on quality of life of continent cutaneous urinary diversion in spinal cord injured patients. SETTING: Department of Urology, Sahlgrenska University Hospital, Göteborg, Sweden. SUBJECTS: A total of 10 patients with spinal cord injury (SCI). METHOD: The patients were operated on with an ileal reservoir (Kock reservoir or T-pouch), Cr-EDTA clearance was determined preoperatively and at follow-up. The patients answered a questionnaire concerning reservoir function, various activities and quality of life. The patient charts were reviewed. RESULTS: One patient died of pulmonary embolism 3 years after surgery. Two patients were reoperated on for reservoir perforation. All patients were satisfied/very satisfied with their reservoirs. Half of them reported improved ability to perform various activities. Eight out of nine patients reported improved quality of life. CONCLUSION: For a selected group of patients with SCI, continent cutaneous urinary diversion provides successful outcome with improved quality of life.
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| 10. |
- Pazooki, David, 1958, et al.
(författare)
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Continent cutaneous urinary diversion is still a valid alternative after cystectomy for bladder carcinoma.
- 2005
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Ingår i: Scand J Urol Nephrol. - : Informa UK Limited. ; 39:6, s. 468-473
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Tidskriftsartikel (refereegranskat)abstract
- Objective. We compared patient opinions concerning reservoir/bladder function as well as quality of life (QOL) after cystectomy for bladder carcinoma and continent cutaneous urinary diversion or orthotopic bladder reconstruction. Material and methods. Fifteen patients with Kock reservoirs (11 females, 4 males) and 11 men with orthotopic bladders answered the European Organization for Research and Treatment of Cancer quality-of-life questionnaire-C30 as well as specially constructed questions concerning reservoir/bladder function. The glomerular filtration rate (GFR) was determined using Cr-EDTA or iohexol clearance. Results. Functioning and global health/QOL scales did not differ between the two groups of operated patients or between diverted patients and gender- and age-matched groups from the general population. The majority of the patients were satisfied/very satisfied with their diversion but more patients were troubled by leakage in the orthotopic bladder group than in the Kock reservoir group. The GFR was similar in the two groups. Conclusion. Continent cutaneous urinary diversion is associated with fewer leakage problems than orthotopic bladder reconstruction after cystectomy for bladder carcinoma.
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| 11. |
- Renklint, Elisabet, et al.
(författare)
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Conversational gaze in light and darkness
- 2012
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Ingår i: Proceedings from FONETIK 2012. - Göteborg : Göteborgs universitet. - 9789163709852 ; , s. 57-60
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The way we use our gaze in face-to-face interaction is an important part of our social behavior. This exploratory study investigates the relationship between mutual gaze and joint silences and overlaps, where speaker changes and backchannels often occur. Seven dyadic conversations between two persons were recorded in a studio. Gaze patterns were annotated in ELAN to find instances of mutual gaze. Part of the study was conducted in total darkness as a way to observe what happens to our gaze-patterns when we cannot see our interlocutor, although the physical face-to-face condition is upheld. The results show a difference in the frequency of mutual gaze in conversation in light and darkness.
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| 12. |
- Svärd, Antonia
(författare)
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Biopolymers and materials from rapeseed straw biorefining
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Rapeseed straw was fractionated through a hydrothermal process into its hemicellulose, lignin and cellulose components. In the first step, hemicellulose-rich fractions were extracted. Xylan-rich fractions with high molecular weight, 30,000 – 50,000 g/mol, were obtained at 110 °C and 1.5 M NaOH. Neutral and acidic conditions yielded extract rich in glucomannan with co-extracted xylan and lignin.After hemicellulose extraction, the straw was subjected to a soda cooking step where the straw was delignified and lignin solubilized. Two cooking times were evaluated in this step. A longer cooking time resulted in a lignin-rich precipitate and a cellulose pulp with a lower content of lignin compared with the shorter cooking time. Analysis showed rapeseed straw lignin consists of syringyl and guaiacyl aromatic structures. Peroxide bleaching of the pulp decreased the lignin content in the cellulose pulp further. Cellulose nanoparticles (CNF and CNC) were isolated from the bleached pulp. The CNF fraction was heterogenous in size while the CNC fraction was more homogenous in size with rod like aspects. Both were highly crystalline, with good thermal stability and high aspect ratio.Thin free-standing films of xylan were cast from water solution with mechanical integrity and very high strain-at-break > 80% even without added plasticizer.A surface modification process was developed where xylan was first pre-activated in alkali. This was followed by an etherification coupling reaction with glycidyl methacrylate and subsequently grafted by interfacial free radical graft polymerization with octadecyl acrylate chains. The resulting grafted xylan became hydrophobic and gained a thermoplastic behavior. It was blended with PCL matrix via melt-extrusion. The grafted xylan was homogeneously distributed within the biocomposite and the PCL matrix was reinforced while at the same time preserving the ability to elongate to tensile strains > 500%. Analogous biocomposites with unmodified xylan in a PCL matrix resulted in heterogenous mixtures and brittle tensile properties.
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| 13. |
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| 14. |
- Svärd, Antonia, 1988-
(författare)
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Extraction of polymeric rapeseed straw hemicelluloses for renewable films
- 2016
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Polymeric hemicelluloses with high molecular weight were extracted from rapeseed straw with a straight forward hydrothermal extraction method, evaluated and refined by statistical factorial screening design and ‘severity factor’ analysis. The influence of the extraction conditions, time, temperature and pH of the extraction liquid, on the composition, molecular weight, yield and properties was unveiled. The initial statistical screening design provided critical knowledge in how the extraction parameters affect yield, lignin and sugar composition as well as molecular weight of the extracts. A more elaborate extraction study which encompassed a greater temperature range and variation of the pH in the hydrothermal liquid combined with ‘severity factor’ modeling on the molecular weight of the extracts provided deeper insights of the effect of the extraction conditions. Water and acid extraction resulted in glucomannan rich extracts. Glucomannan isolated with acid was more degraded than the glucomannan isolated with water. From an environmentally perspective water extraction is preferred to obtain glucomannan due to the corrosive nature of acid. The molecular weight of the dissolved glucomannan during water extraction increased with temperature. Xylan was co-extracted at the higher extraction temperature. Alkaline extraction yielded an extract rich in xylan, where the total amount and the molecular weight of xylan increased with alkali charge. The xylan was more degraded at the highest temperature, 140 °C, and the highest alkali charge. All different extractions yielded co-extracted lignin, especially during high charge of alkali, but the straw was never fully delignified or the cellulose fibres liberated. Some extracts, selected from the statistical screening study, were utilized as raw materials for renewable plastic films. The glucomannan films were very fragile, while the xylan films had remarkable strain-at-break of 60 – 80 % without any added plasticizer.
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| 15. |
- Svärd, Antonia, 1988-, et al.
(författare)
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Modified and thermoplastic rapeseed straw xylan : A renewable additive in PCL biocomposites
- 2018
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Ingår i: Industrial crops and products (Print). - : Elsevier. - 0926-6690 .- 1872-633X. ; 119, s. 73-82
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Tidskriftsartikel (refereegranskat)abstract
- Xylan extracted from rapeseed straw was chemically modified to gain hydrophobic and thermoplastic properties via macroinitiator formation followed by a free radical grafting-from polymerization with octadecyl acrylate. Biocomposites were then prepared by incorporation of 5 or 20% (w/w) rapeseed straw xylan into a poly(epsilon-caprolactone) (PCL) matrix by melt extrusion. The grafted xylan was homogeneously distributed within the biocomposite and reinforced the PCL matrix while at the same time preserving the ability to elongate to tensile strains > 500%. Analogous biocomposites made from unmodified xylan in a PCL matrix resulted in heterogeneous mixtures and brittle tensile properties.
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| 16. |
- Svärd, Antonia, et al.
(författare)
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Rapeseed straw as a renewable source of hemicelluloses : Extraction, characterization and film formation
- 2015
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Ingår i: Carbohydrate Polymers. - : Elsevier BV. - 0144-8617 .- 1879-1344. ; 133, s. 179-186
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Tidskriftsartikel (refereegranskat)abstract
- Polymeric hemicelluloses were extracted by autohydrolysis and alkali from a biomass feed consisting of the stems of rapeseed straw according to a full statistical factorial screening design. Water extraction yielded fractions rich in galactoglucomannan, while alkaline extraction yielded primarily xylan. The extracted galactoglucomannan and xylans had similar molecular weights, while the yield of xylan was higher than the yield of galactoglucomannan. The extracted hemicellulose fractions also contained some lignin (7-15%) and traces of Ca, K, Na, and Si. Free-standing films were prepared from the hemicellulose fractions with different xylan:galactoglucomannan ratios. The rapeseed xylan films showed strain-to-break values >60% without any added plasticizers.
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| 17. |
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| 18. |
- Svärd, Antonia, 1988-, et al.
(författare)
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Rapeseed Straw Biorefinery Process
- 2019
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Ingår i: ACS Sustainable Chemistry and Engineering. - : American Chemical Society (ACS). - 2168-0485. ; 7:1, s. 790-801
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Tidskriftsartikel (refereegranskat)abstract
- A rapeseed straw biorefinery process was demonstrated with more than 50% of the straw recovered as products. Xylan with a weight-average molecular weight of 56 760 g/mol was extracted in an alkaline step. The straw residue was subjected to soda pulping, resulting in cellulose-rich fibers and a lignin-rich liquid fraction. The lignin contained syringyl and guaiacyl aromatic structural units in a 1/0.75 ratio. The cellulose pulp was bleached, resulting in a cellulose fraction of 85% purity and a crystallinity index (CI) of 83%. Two grades of nanocellulose, CNF and CNC, were isolated from the bleached pulp. The CNF was very heterogeneous in size with an average diameter of 4 nm and an average length of 1177 nm. The CNC had an average diameter of 6 nm and an average particle length of 193 nm. CNF and CNC had good thermal stability and an aspect ratio of 294 and 32, respectively.
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| 19. |
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| 20. |
- Svärd, Antonia, et al.
(författare)
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Rapeseed straw polymeric hemicelluloses obtained by extraction methods based on severity factor
- 2017
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Ingår i: INDUSTRIAL CROPS AND PRODUCTS. - : Elsevier. - 0926-6690. ; 95, s. 305-315
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Tidskriftsartikel (refereegranskat)abstract
- Rapeseed straw consists of a hard epidermis that is rich in hemicellulose and lignin and a sponge-like interior that consists mainly of cellulose. The stems were subjected to water, alkali or acid as extraction medium. The effects of the extraction conditions were quantified using severity factors and by comparing the effects of different extraction pHs, temperatures and times. Extraction with alkali resulted in a higher yield, 47 g/100 g straw in, compared to water, 6 g/100 g straw in, or an acidic, 5 g/100 g straw in, extraction process. An increase in temperature improved the extraction yield; in particular, more xylan was extracted at an elevated temperature and higher alkalinity. However, at high alkalinity, increased extraction temperatures led to a reduction in the recovery of glucomannan. The highest molecular weights (similar to 35,000 g/mol) of the extracted hemicelluloses were obtained using extraction procedures with 1.5 M NaOH at 110 degrees C and autohydrolysis at 150 degrees C. While these two parameter settings had very similar severity factors, extraction under basic conditions afforded an extract rich in xylan and low in lignin content, whereas autohydrolysis generated a glucomannan-rich extract.
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| 21. |
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| 22. |
- Zhao, Weifeng, 1987-
(författare)
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Chemical Pathways to Electrically Conductive Hemicellulose Hydrogels
- 2014
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Hydrogels have been extensively explored and are widely used in diverse biomedical applications, such as scaffolds for tissue engineering and vehicles for drug delivery. As one type of important natural polymer-based hydrogel, hemicellulose hydrogels have interesting attributes, including being renewable, non-toxic, biocompatible, biodegradable, and abundantly available. A prominent way to extend their potential is by combining them with desirable properties from other materials. The focus of this thesis is to develop a new family of electrically conductive hemicellulose-based hydrogels (ECHHs) using O-acetyl-galactoglucomannan (AcGGM) and aniline oligomers through different chemical pathways.A first approach to synthesize the ECHHs includes two steps: first, carboxylated AcGGM (C-AcGGM) is dissolved with glycidyl methacrylate, followed by polymerization initiated by ammonium persulfate; second, the resulting hydrogels are covalently coupled to varying amounts of aniline tetramer (AT), which is homogeneously distributed throughout the network. The swelling ratios of C-AcGGM hydrogels decrease as the degree of substitution of maleic anhydride increases. The swelling ratios and conductivities of ECHHs are tuned by the AT content.To develop a simpler and greener approach to synthesize ECHHs under ambient conditions, AcGGM is in-situ cross-linked in the presence of aniline pentamer (AP) in basic water. Hydrogel equilibrium swelling ratios (ESRs) vary from 12.7 to 10.4, regulated by cross-linker concentration. The ESRs are also tuned from 9.6 to 6.0 by changing the AP contents from 10 % (w/w) to 40 % (w/w) while simultaneously altering conductivities from 9.05×10-9 to 1.58×10-6 S/cm.ECHHs with controllable conductivity, tunable swelling behavior and acceptable mechanical properties extend the applications of hemicellulose to include e.g. biosensors and electronic devices.
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