Molecular doping is a powerful method to fine‐tune the thermoelectric properties of organic semiconductors, in particular to impart the requisite electrical conductivity. The incorporation of ...molecular dopants can, however, perturb the microstructure of semicrystalline organic semiconductors, which complicates the development of a detailed understanding of structure–property relationships. To better understand how the doping pathway and the resulting dopant counterion influence the thermoelectric performance and transport properties, a new dimer dopant, (N‐DMBI)2, is developed. Subsequently, FBDPPV is then n‐doped with dimer dopants (N‐DMBI)2, (RuCp*mes)2, and the hydride‐donor dopant N‐DMBI‐H. By comparing the UV–vis–NIR absorption spectra and morphological characteristics of the doped polymers, it is found that not only the doping mechanism, but also the shape of the counterion strongly influence the thermoelectric properties and transport characteristics. (N‐DMBI)2, which is a direct electron‐donating dopant with a comparatively small, relatively planar counterion, gives the best power factor among the three systems studied here. Additionally, temperature‐dependent conductivity and Seebeck coefficient measurements differ between the three dopants with (N‐DMBI)2 yielding the best thermoelectric properties. The results of this study of dopant effects on thermoelectric properties provide insight into guidelines for future organic thermoelectrics.
A novel dimeric n‐dopant (N‐DMBI)2, is designed and synthesized to understand the effects of molecular dopants on thermoelectric properties. This study shows how the counterion shape, and the doping mechanism affect the thermoelectric performance and the transport pathway of n‐type conducting polymers, and reveals what type of n‐dopant is preferable.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A family of neutral bis-cyclometalated iridium complexes Ir(C∧N)2(LX) has been investigated as ECL labels under immunoassay conditions. Among them, the complex based on phenylphenanthridine (pphent) ...as the C∧N ligand, exhibits outstanding performance and it is a candidate to substitute the commercially available Ru-based label in diagnostics.
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IJS, KILJ, NUK, PNG, UL, UM
The ability to discriminate between different facial expressions is fundamental since the first stages of postnatal life. The aim of this study is to investigate whether 2-days-old newborns are ...capable to discriminate facial expressions of emotions as they naturally take place in everyday interactions, that is in motion. When two dynamic displays depicting a happy and a disgusted facial expression were simultaneously presented (i.e., visual preference paradigm), newborns did not manifest any visual preference (Experiment 1). Nonetheless, after being habituated to a happy or disgusted dynamic emotional expression (i.e., habituation paradigm), newborns successfully discriminated between the two (Experiment 2). These results indicate that at birth newborns are sensitive to dynamic faces expressing emotions.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We report here the long-term clinical and immunological results of four living-donor kidney transplant patients given autologous bone marrow-derived mesenchymal stromal cells (MSCs) as part of a ...phase 1 study focused on the safety and feasibility of this cell therapy. According to study protocols implemented over time, based on initial early safety findings, the patients were given MSC at day 7 posttransplant (
= 2) or at day -1 pretransplant (
= 2) and received induction therapy with basiliximab and low-dose rabbit anti-thymocyte globulin (RATG) or RATG alone, and were maintained on low-dose ciclosporin (CsA)/mycophenolate mofetil (MMF). All MSC-treated patients had stable graft function during the 5- to 7-year follow-up, without increased susceptibility to infections or neoplasm. In three MSC recipients, but not historical control patients, circulating memory CD8
T cell percentages remained lower than basal, coupled with persistent reduction of
donor-specific cytotoxicity. Two patients showed a long-lasting increase in the regulatory T cell/memory CD8
T cell ratio, paralleled by high circulating levels of naïve and transitional B cells. In one of these two patients, CsA was successfully discontinued, and currently the low-dose MMF monotherapy is on the tapering phase. The study shows that MSC therapy is safe in the long term and could promote a pro-tolerogenic environment in selected patients. Extensive immunomonitoring of MSC-treated kidney transplant recipients could help selection of patients for safe withdrawal of maintenance immunosuppressive drugs (NCT00752479 and NCT02012153).
Electrically pumped lasing from hybrid organic–inorganic metal‐halide perovskite semiconductors could lead to nonepitaxial diode lasers that are tunable throughout the visible and near‐infrared ...spectrum; however, a viable laser diode architecture has not been demonstrated to date. Here, an important step toward this goal is achieved by demonstrating two distinct distributed feedback light‐emitting diode architectures that achieve low threshold, optically pumped lasing. Bottom‐ and top‐emitting perovskite light‐emitting diodes are fabricated on glass and Si substrates, respectively, using a polydimethylsiloxane stamp in the latter case to nanoimprint a second‐order distributed feedback grating directly into the methylammonium lead iodide active layer. The devices exhibit room temperature thresholds as low as ≈6 µJ cm−2, a peak external quantum efficiency of ≈0.1%, and a maximum current density of ≈2 A cm−2 that is presently limited by degradation associated with excessive leakage current. In this low current regime, electrical injection does not adversely affect the optical pump threshold, leading to a projected threshold current density of ≈2 kA cm−2. Operation at low temperature can significantly decrease this threshold, but must overcome extrinsic carrier freeze‐out in the doped organic transport layers to maintain a reasonable drive voltage.
Optically pumped lasing is demonstrated in distributed feedback hybrid perovskite light emitting diodes fabricated on both glass and Si substrates. Thresholds as low as ≈6 µJ cm−2 at room temperature are achieved and retained under ≈2 A cm−2 of pulsed electrical excitation.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Chemical doping is a key process for controlling the electronic properties of molecular semiconductors, including their conductivity and work function. A common limitation of n-doped polymers is ...their instability under ambient conditions, which has imposed restrictions on the characterisation and device application of n-doped polymers. In this study, sequential n-doping with organometallic dopants was performed on thin films of polymeric semiconductors with naphthalene diimide and perylene diimide-based backbones. Moderate ambient stability was achieved with (RuCp*Mes)
2
, {Cp* = pentamethylcyclopentadienyl; Mes = 1,3,5-trimethylbenzene}, which is in striking contrast to the unstable, n-doped state obtained with cobaltocene, a simple one-electron reductant. The highly cathodic, effective redox potential of (RuCp*Mes)
2
,
ca.
−2.0 V
vs.
ferrocene, suppresses the back electron transfer reaction and the subsequent dopant loss in air, which gives rise to the observed air stability. It also allows a perylene diimide-based polymer to be reduced to a state in which the repeat units are largely dianionic. Photoelectron measurements show that the ionization potential of the heavily doped polymer is
ca.
3.9 eV. Our findings show that chemical doping with (RuCp*Mes)
2
is an effective method to produce highly stable, n-doped conjugated polymers.
Air stability of n-doped polymers is improved by using a strongly reducing, dimeric dopant instead of cobaltocene.
Here we report the case of successful immune tolerance induction in a living‐donor kidney transplant recipient remotely treated with autologous bone marrow‐derived mesenchymal stromal cells (MSC). ...This case report, which to the best of our knowledge is the first in the world in this setting, provides evidence that the modulation of the host immune system with MSC can enable the safe withdrawal of maintenance immunosuppressive drugs while preserving optimal long‐term kidney allograft function.
This report provides the evidence that autologous BM‐MSC infusion induces a pro‐tolerogenic immune environment, thus allowing complete discontinuation of antirejection drugs in kidney transplantation
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract Control of electrical doping is indispensable in any semiconductor device, and both efficient hole and electron doping are required for many devices. In organic semiconductors, however, ...electron doping has been essentially more problematic compared to hole doping because in general organic semiconductors have low electron affinities and require dopants with low ionization potentials that are often air-sensitive. Here, we adapt an efficient molecular doping method, so-called ion-exchange doping, to dope electrons in a polymeric semiconductor. We initially reduce the polymeric semiconductor using one electron transfer from molecular dopants, and then the ionized dopants in the resulting air-unstable films are replaced with secondary ions via cation exchange. Improved ambient stability and crystallinity of the doped polymeric semiconductors are achieved when a specific bulky molecular cation was chosen as the secondary ion, compared to conventional methods. The presented strategy can overcome the trade-off relationship between reducing capability and ambient stability in molecular dopants, and a wider selection of dopant ions will help to realize ambient-stable electron conductors.
Seeing Touches Early in Life Addabbo, Margaret; Longhi, Elena; Bolognini, Nadia ...
PloS one,
09/2015, Volume:
10, Issue:
9
Journal Article
Peer reviewed
Open access
The sense of touch provides fundamental information about the surrounding world, and feedback about our own actions. Although touch is very important during the earliest stages of life, to date no ...study has investigated infants' abilities to process visual stimuli implying touch. This study explores the developmental origins of the ability to visually recognize touching gestures involving others. Looking times and orienting responses were measured in a visual preference task, in which participants were simultaneously presented with two videos depicting a touching and a no-touching gesture involving human body parts (face, hand) and/or an object (spoon). In Experiment 1, 2-day-old newborns and 3-month-old infants viewed two videos: in one video a moving hand touched a static face, in the other the moving hand stopped before touching it. Results showed that only 3-month-olds, but not newborns, differentiated the touching from the no-touching gesture, displaying a preference for the former over the latter. To test whether newborns could manifest a preferential visual response when the touched body part is different from the face, in Experiment 2 newborns were presented with touching/no-touching gestures in which a hand or an inanimate object-i.e., a spoon- moved towards a static hand. Newborns were able to discriminate a hand-to-hand touching gesture, but they did not manifest any preference for the object-to-hand touch. The present findings speak in favour of an early ability to visually recognize touching gestures involving the interaction between human body parts.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In primates and adult humans direct understanding of others' action is provided by mirror mechanisms matching action observation and action execution (e.g. Casile, Caggiano & Ferrari, 2011). Despite ...the growing body of evidence detailing the existence of these mechanisms in the adult human brain, their origins and early development are largely unknown. In this study, for the first time, electromyographic (EMG) measures were used to shed light on the emergence of mirror motor mechanisms in infancy. EMG activity was recorded while 6‐ and 3‐month‐old infants watched two videos displaying an agent reaching for, grasping and bringing an object either to the mouth or to the head. Results indicate that the motor system of 6‐month‐olds, but not 3‐month‐olds, was recruited and selectively modulated during observation of the goal‐directed actions, favoring the idea that mirror mechanisms driving action understanding gradually emerge during early development.
In primates and adult humans direct understanding of others' action is provided by mirror mechanisms matching action observation and action execution (e.g. Casile et al., 2011). Despite the growing body of evidence detailing the existence of these mechanisms in the adult human brain, their origins and early development are largely unknown. In this study, for the first time, electromyographic (EMG) measures were used to shed light on the emergence of mirror motor mechanisms in infancy.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
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