| 1. |
- Gerasimov, Jennifer, et al.
(författare)
-
A Biomimetic Evolvable Organic Electrochemical Transistor
- 2021
-
Ingår i: Advanced Electronic Materials. - : Wiley. - 2199-160X. ; 7:11
-
Tidskriftsartikel (refereegranskat)abstract
- Biomimicry at the hardware level is expected to overcome at least some of the challenges, including high power consumption, large footprint, two-dimensionality, and limited functionality, which arise as the field of artificial intelligence matures. One of the main attributes that allow biological systems to thrive is the successful interpretation of and response to environmental signals. Taking inspiration from these systems, the first demonstration of using multiple environmental inputs to trigger the formation and control the growth of an evolvable synaptic transistor is reported here. The resulting transistor exhibits long-term changes in the channel conductance at a fixed gate voltage. Biomimetic logic circuits are investigated based on this evolvable transistor that implement temperature and pressure inputs to achieve higher order processes like self-regulation of synaptic strength and coincidence detection.
|
|
| 2. |
- Gerasimov, Jennifer Yevgenia, 1985-, et al.
(författare)
-
Rational Materials Design for In Operando Electropolymerization of Evolvable Organic Electrochemical Transistors
- 2022
-
Ingår i: Advanced Functional Materials. - : John Wiley and Sons Inc. - 1616-301X .- 1616-3028. ; 32
-
Tidskriftsartikel (refereegranskat)abstract
- Organic electrochemical transistors formed by in operando electropolymerization of the semiconducting channel are increasingly becoming recognized as a simple and effective implementation of synapses in neuromorphic hardware. However, very few studies have reported the requirements that must be met to ensure that the polymer spreads along the substrate to form a functional conducting channel. The nature of the interface between the substrate and various monomer precursors of conducting polymers through molecular dynamics simulations is investigated, showing that monomer adsorption to the substrate produces an increase in the effective monomer concentration at the surface. By evaluating combinatorial couples of monomers baring various sidechains with differently functionalized substrates, it is shown that the interactions between the substrate and the monomer precursor control the lateral growth of a polymer film along an inert substrate. This effect has implications for fabricating synaptic systems on inexpensive, flexible substrates. © 2022 The Authors.
|
|
| 3. |
- Aydemir, Umut, et al.
(författare)
-
In situ assembly of an injectable cardiac stimulator
- 2024
-
Ingår i: Nature Communications. - : NATURE PORTFOLIO. - 2041-1723. ; 15:1
-
Tidskriftsartikel (refereegranskat)abstract
- Without intervention, cardiac arrhythmias pose a risk of fatality. However, timely intervention can be challenging in environments where transporting a large, heavy defibrillator is impractical, or emergency surgery to implant cardiac stimulation devices is not feasible. Here, we introduce an injectable cardiac stimulator, a syringe loaded with a nanoparticle solution comprising a conductive polymer and a monomer that, upon injection, forms a conductive structure around the heart for cardiac stimulation. Following treatment, the electrode is cleared from the body, eliminating the need for surgical extraction. The mixture adheres to the beating heart in vivo without disrupting its normal rhythm. The electrofunctionalized injectable cardiac stimulator demonstrates a tissue-compatible Young's modulus of 21 kPa and a high conductivity of 55 S/cm. The injected electrode facilitates electrocardiogram measurements, regulates heartbeat in vivo, and rectifies arrhythmia. Conductive functionality is maintained for five consecutive days, and no toxicity is observed at the organism, organ, or cellular levels. Heart pacing devices are bulky or rely on surgery. Here, the authors present an injectable cardiac stimulator based on a nanoparticle solution which attaches to the heart and forms a conductive path to the skin for external connection. It can regulate heartbeats and is thereafter cleared from the body.
|
|
| 4. |
- Hedell, Ronny, 1985, et al.
(författare)
-
Enhanced low-template DNA analysis conditions and investigation of allele dropout patterns
- 2015
-
Ingår i: Forensic Science International: Genetics. - : Elsevier BV. - 1878-0326 .- 1872-4973. ; 14, s. 61-75
-
Tidskriftsartikel (refereegranskat)abstract
- Forensic DNA analysis applying PCR enables profiling of minute biological samples. Enhanced analysis conditions can be applied to further push the limit of detection, coming with the risk of visualising artefacts and allele imbalances. We have evaluated the consecutive increase of PCR cycles from 30 to 35 to investigate the limitations of low-template (LT) DNA analysis, applying the short tandem repeat (STR) analysis kit PowerPlex ESX 16. Mock crime scene DNA extracts of four different quantities (from around 8-84 pg) were tested. All PCR products were analysed using 5, 10 and 20 capillary electrophoresis (CE) injection seconds. Bayesian models describing allele dropout patterns, allele peak heights and heterozygote balance were developed to assess the overall improvements in EPG quality with altered PCR/CE settings. The models were also used to evaluate the impact of amplicon length, STR marker and fluorescent label on the risk for allele dropout. The allele dropout probability decreased for each PCR cycle increment from 30 to 33 PCR cycles. Irrespective of DNA amount, the dropout probability was not affected by further increasing the number of PCR cycles. For the 42 and 84 pg samples, mainly complete DNA profiles were generated applying 32 PCR cycles. For the 8 and 17 pg samples, the allele dropouts decreased from 100% using 30 cycles to about 75% and 20%, respectively. The results for 33, 34 and 35 PCR cycles indicated that heterozygote balance and stutter ratio were mainly affected by DNA amount, and not directly by PCR cycle number and CE injection settings. We found 32 and 33 PCR cycles with 10 CE injection seconds to be optimal, as 34 and 35 PCR cycles did not improve allele detection and also included CE saturation problems. We find allele dropout probability differences between several STR markers. Markers labelled with the fluorescent dyes CXR-ET (red in electropherogram) and TMR-ET (shown as black) generally have higher dropout risks compared with those labelled with JOE (green) and fluorescein (blue). Overall, the marker D10S1248 has the lowest allele dropout probability and D8S1179 the highest. The marker effect is mainly pronounced for 30-32 PCR cycles. Such effects would not be expected if the amplification efficiencies were identical for all markers. Understanding allele dropout risks and the variability in peak heights and balances is important for correct interpretation of forensic DNA profiles.
|
|
| 5. |
- Movérare-Skrtic, Sofia, et al.
(författare)
-
Osteoblast-derived WNT16 represses osteoclastogenesis and prevents cortical bone fragility fractures.
- 2014
-
Ingår i: Nature Medicine. - : Springer Science and Business Media LLC. - 1078-8956 .- 1546-170X. ; 20:11, s. 1279-88
-
Tidskriftsartikel (refereegranskat)abstract
- The WNT16 locus is a major determinant of cortical bone thickness and nonvertebral fracture risk in humans. The disability, mortality and costs caused by osteoporosis-induced nonvertebral fractures are enormous. We demonstrate here that Wnt16-deficient mice develop spontaneous fractures as a result of low cortical thickness and high cortical porosity. In contrast, trabecular bone volume is not altered in these mice. Mechanistic studies revealed that WNT16 is osteoblast derived and inhibits human and mouse osteoclastogenesis both directly by acting on osteoclast progenitors and indirectly by increasing expression of osteoprotegerin (Opg) in osteoblasts. The signaling pathway activated by WNT16 in osteoclast progenitors is noncanonical, whereas the pathway activated in osteoblasts is both canonical and noncanonical. Conditional Wnt16 inactivation revealed that osteoblast-lineage cells are the principal source of WNT16, and its targeted deletion in osteoblasts increases fracture susceptibility. Thus, osteoblast-derived WNT16 is a previously unreported key regulator of osteoclastogenesis and fracture susceptibility. These findings open new avenues for the specific prevention or treatment of nonvertebral fractures, a substantial unmet medical need.
|
|
| 6. |
- Pettersson, Håkan, et al.
(författare)
-
Intersubband photoconductivity of self-assembled InAs quantum dots embedded in InP
- 2004
-
Ingår i: Journal of Applied Physics. - : American Institute of Physics (AIP). - 0021-8979 .- 1089-7550. ; 95:4, s. 1829-1831
-
Tidskriftsartikel (refereegranskat)abstract
- The results from photoconductivity (PC) measurements on InAs dots embedded in InP are presented. The PC technique is recently applied to the study of InAs dots embedded in matrices of GaAs and Al0.3Ga0.7As matrix, respectively. It is demonstrated that this technique reveals important new physical insight into the electronic structure of the InAs/InP dots, information that cannot easily be obtained by other techniques.
|
|
| 7. |
- Priyadarshini, Diana, et al.
(författare)
-
Enzymatically Polymerized Organic Conductors on Model Lipid Membranes
- 2023
-
Ingår i: Langmuir. - : AMER CHEMICAL SOC. - 0743-7463 .- 1520-5827. ; 39:23, s. 8196-8204
-
Tidskriftsartikel (refereegranskat)abstract
- Seamless integration between biological systems and electricalcomponents is essential for enabling a twinned biochemical-electricalrecording and therapy approach to understand and combat neurologicaldisorders. Employing bioelectronic systems made up of conjugated polymers,which have an innate ability to transport both electronic and ioniccharges, provides the possibility of such integration. In particular,translating enzymatically polymerized conductive wires, recently demonstratedin plants and simple organism systems, into mammalian models, is ofparticular interest for the development of next-generation devicesthat can monitor and modulate neural signals. As a first step towardachieving this goal, enzyme-mediated polymerization of two thiophene-basedmonomers is demonstrated on a synthetic lipid bilayer supported ona Au surface. Microgravimetric studies of conducting films polymerizedin situ provide insights into their interactions with a lipid bilayermodel that mimics the cell membrane. Moreover, the resulting electricaland viscoelastic properties of these self-organizing conducting polymerssuggest their potential as materials to form the basis for novel approachesto in vivo neural therapeutics.
|
|
| 8. |
- Risveden, Klas, et al.
(författare)
-
The region ion sensitive field effect transistor, a novel bioelectronic nanosensor
- 2007
-
Ingår i: Biosensors & Bioelectronics. - : Elsevier BV. - 0956-5663 .- 1873-4235. ; 22:12, s. 3105-3112
-
Tidskriftsartikel (refereegranskat)abstract
- A novel type of bioelectronic region ion sensitive field effect transistor (RISFET) nanosensor was constructed and demonstrated on two different sensor chips that could measure glucose with good linearity in the range of 0-0.6 mM and 0-0.3 mM with a limit of detection of 0.1 and 0.04 mM, respectively. The sensor is based on the principle of focusing charged reaction products with an electrical field in a region between the sensing electrodes. For glucose measurements, negatively charged gluconate ions were gathered between the sensing electrodes. The signal current response was measured using a low-noise pico ammeter (pA). Two different sizes of the RISFET sensor chips were constructed using conventional electron beam lithography. The measurements are done in partial volumes mainly restricted by the working distance between the sensing electrodes (790 and 2500 nm, respectively) and the influence of electrical fields that are concentrating the ions. The sensitivity was 28 pA/mM (2500 nm) and 830 pA/mM (790 nm), respectively. That is an increase in field strength by five times between the sensing electrodes increased the sensitivity by 30 times. The volumes expressed in this way are in low or sub femtoliter range. Preliminary studies revealed that with suitable modification and control of parameters such as the electric control signals and the chip electrode dimensions this sensor could also be used as a nanobiosensor by applying single enzyme molecule trapping. Hypotheses are given for impedance factors of the RISFET conducting channel. (c) 2007 Elsevier B.V. All rights reserved.
|
|
| 9. |
- Tommasini, Giuseppina, et al.
(författare)
-
Seamless integration of bioelectronic interface in an animal model via in vivo polymerization of conjugated oligomers
- 2022
-
Ingår i: Bioactive Materials. - : Elsevier BV. - 2452-199X. ; 10, s. 107-116
-
Tidskriftsartikel (refereegranskat)abstract
- Leveraging the biocatalytic machinery of living organisms for fabricating functional bioelectronic interfaces, in vivo, defines a new class of micro-biohybrids enabling the seamless integration of technology with living biological systems. Previously, we have demonstrated the in vivo polymerization of conjugated oligomers forming conductors within the structures of plants. Here, we expand this concept by reporting that Hydra, an invertebrate animal, polymerizes the conjugated oligomer ETE-S both within cells that expresses peroxidase activity and within the adhesive material that is secreted to promote underwater surface adhesion. The resulting conjugated polymer forms electronically conducting and electrochemically active μm-sized domains, which are inter-connected resulting in percolative conduction pathways extending beyond 100 μm, that are fully integrated within the Hydra tissue and the secreted mucus. Furthermore, the introduction and in vivo polymerization of ETE-S can be used as a biochemical marker to follow the dynamics of Hydra budding (reproduction) and regeneration. This work paves the way for well-defined self-organized electronics in animal tissue to modulate biological functions and in vivo biofabrication of hybrid functional materials and devices.
|
|
| 10. |
- Berndes, Göran, 1966, et al.
(författare)
-
Multifunctional biomass production systems - an overview with presentation of specific applications in India and Sweden
- 2008
-
Ingår i: Biofuels, Bioproducts and Biorefining. - : Wiley. - 1932-104X .- 1932-1031. ; 2:1, s. 16-25
-
Tidskriftsartikel (refereegranskat)abstract
- This perspective discusses multi-functional biomass production systems, which are located, designed, integrated and managed so as to provide specific environmental services, in addition to biomass supply. Besides discussing the general concept and outlining a range of different possible applications, we present in somewhat more detail specific applications of such systems for the cases of Sweden and India. The overall conclusion is that the environmental benefits from a large-scale establishment of multi-functional biomass production systems could be substantial. Given that suitable mechanisms to put a premium on the provided environmental services can be identified and implemented, additional revenues can be linked to biomass production systems and this could enhance the socioeconomic attractiveness and significantly improve the competitiveness of the produced biomass on the market. The provision of additional environmental services also contributes to local sustainable development, which is in many cases a prerequisite for local support for the production systems.
|
|
