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281.
Air‐stable and soluble tetrabutylammonium fluoride (TBAF) is demonstrated as an efficient n‐type dopant for the conjugated polymer ClBDPPV. Electron transfer from F? anions to the π‐electron‐deficient ClBDPPV through anion–π electronic interactions is strongly corroborated by the combined results of electron spin resonance, UV–vis–NIR, and ultraviolet photoelectron spectroscopy. Doping of ClBDPPV with 25 mol% TBAF boosts electrical conductivity to up to 0.62 S cm?1, among the highest conductivities that have been reported for solution‐processed n‐type conjugated polymers, with a thermoelectric power factor of 0.63 µW m?1 K?2 in air. Importantly, the Seebeck coefficient agrees with recently published correlations to conductivity. Moreover, the F?‐doped ClBDPPV shows significant air stability, maintaining the conductivity of over 0.1 S cm?1 in a thick film after exposure to air for one week, to the best of our knowledge the first report of an air‐stable solution‐processable n‐doped conductive polymer with this level of conductivity. The result shows that using solution‐processable small‐anion salts such as TBAF as an n‐dopant of organic conjugated polymers possessing lower LUMO (lowest unoccupied molecular orbital), less than ?4.2 eV) can open new opportunities toward high‐performance air‐stable solution‐processable n‐type thermoelectric (TE) conjugated polymers.  相似文献   
282.
The scientific community organises its relationships into network patterns, where the nodes are individuals (scientists) and the links are acquaintance and common work, usually presented at workshops and conferences and/or published in books and scientific journals. A references review on Population Studies by Italian scientists is delivered every two years by the Demography Section of the Italian Statistical Society; the review is exhaustive for academic demographers. In this paper, the properties of the demographers' network in 1998-1999 are evaluated, with the aim of identifying factors which may influence collaborative relations among actors. The probability of cooperation between couples (dyads) of demographers is modelled, conditionally on observed characteristics of the dyad (sex, academic position, university affiliation). Main results suggest that “closeness”, defined in a wider sense and not simply as geographical proximity, plays a major role in determining actors' relationships.  相似文献   
283.
IL-12 has been shown to be involved in the pathogenesis of Th1-mediated autoimmune diseases, but its role in antibody-mediated autoimmune pathologies is still unclear. We investigated the effects of exogenous and endogenous IL-12 in experimental autoimmune myasthenia gravis (EAMG). EAMG is an animal model for myasthenia gravis, a T cell-dependent, autoantibody-mediated disorder of neuromuscular transmission caused by antibodies to the muscle nicotinic acetylcholine receptor (AChR). Administration of IL-12 with Torpedo AChR (ToAChR) to C57BL/6 (B6) mice resulted in increased ToAChR-specific IFN-gamma production and increased anti-ToAChR IgG2a serum antibodies compared with B6 mice primed with ToAChR alone. These changes were associated with earlier and greater neurophysiological evidence of EAMG in the IL-12-treated mice, and reduced numbers of AChR. By contrast, when IL-12-deficient mice were immunized with ToAChR, ToAChR-specific Th1 cells and anti-ToAChR IgG2a serum antibodies were reduced compared to ToAChR-primed normal B6 mice, and the IL-12-deficient mice showed almost no neurophysiological evidence of EAMG and less reduction in AChR. These results indicate an important role of IL-12 in the induction of an antibody-mediated autoimmune disease, suggest that Th1-dependent complement-fixing IgG2a anti-AChR antibodies are involved in the pathogenesis of EAMG, and help to account for the lack of correlation between anti-AChR levels and clinical disease seen in many earlier studies.  相似文献   
284.
Aim of this work is the analytical solution of the time-independent Schrödinger equation for the system of two electrons running along two parallel quantum wires. The solution has been obtained by means of a series expansion using the Frobenius method. A final analysis of the results has been carried out and the two-particle electron densities for several values of the distance between the wires and of the system energy are reported.  相似文献   
285.
The temporomandibular joint (TMJ) disc lacks functional replacement after discectomy. We investigated tissue-engineered bilayer polylactide (PLA) discs and autologous adipose stem cells (ASCs) as a potential replacement for the TMJ disc. These ASC discs were pre-cultured either in control or in differentiation medium, including transforming growth factor (TGF)-β1 for one week. Prior to implantation, expression of fibrocartilaginous genes was measured by qRT-PCR. The control and differentiated ASC discs were implanted, respectively, in the right and left TMJs of rabbits for six (n = 5) and 12 months (n = 5). Thereafter, the excised TMJ areas were examined with cone beam computed tomography (CBCT) and histology. No signs of infection, inflammation or foreign body reactions were detected at histology, whereas chronic arthrosis and considerable condylar hypertrophy were observed in all operated joints at CBCT. The left condyle treated with the differentiated ASC discs appeared consistently smoother and more sclerotic than the right condyle. The ASC disc replacement resulted in dislocation and morphological changes in the rabbit TMJ. The ASC discs pre-treated with TGF-β1 enhanced the condylar integrity. While adverse tissue reactions were not shown, the authors suggest that with improved attachment and design, the PLA disc and biomaterial itself would hold potential for TMJ disc replacement.  相似文献   
286.
A retrospective study was conducted to examine aripiprazole's effectiveness and safety in a naturalistic treatment setting in both inpatients and outpatients affected by schizophrenia and other psychotic disorders. All patients with schizophrenia, schizoaffective and delusional disorders, and schizoid and schizotypal personality disorders treated with aripiprazole from March 1, 2005, to March 1, 2006, in the authors' community mental health service were divided into outpatient (n=26) and inpatient (n=17) groups; the average treatment periods were 204 days and 25 days, respectively. Effectiveness was evaluated by improvement of symptoms (a 25% reduction of Brief Psychiatric Rating Scale [BPRS] score from baseline) and functioning level (a 50% increase of Global Assessment of Functioning [GAF] scale score from baseline), as well as dropout rate. Adverse effects and their impact on treatment course were also evaluated. The final scores of the 2 scales showed a statistically significant difference from baseline (BPRS: p  相似文献   
287.
The impact of acoustic and optical phonon scattering on the performance of CNT-FETs is investigated using a full-quantum transport model within the NEGF formalism. Different gate lengths, dielectric materials and chiralities are considered. It is shown that the use of a high-κ dielectric lowers the off-current dominated by phonon-assisted band-to-band tunneling. The device scalability is demonstrated: with the oxide thickness fixed to 1.5 nm, good performance is obtained with 15 nm and 10 nm gate lengths with SiO2 and HfO2 gate dielectrics, respectively. The role of phonon scattering in CNT-FETs of different chiralities is investigated for the HfO2 devices. A similar analysis has also been carried out for source/drain underlap geometries. The results confirm that the calculation of the off-currents and delay times is strongly influenced by phonon scattering.  相似文献   
288.
A review of current processing practices in preparation of recombinant single chain antibody fragments is presented. Single chain antibody fragments which are superior to their Fab and IgG counterparts due to their higher affinity for target antigens while imposing minimal antigenicity in recipient hosts, have sparked breakthroughs in immunology and the medical field at large. The rapidly increasing market demand for pure single chain antibodies for research and therapeutic applications, necessitates viable manufacture routes that can produce large amounts of these antibodies efficiently and as cheaply as possible. Medium- to high-producing expression systems reported for recombinant single chain antibody production are reviewed, and their reported or potential success for efficient commercial-viable preparation of pure antibodies discussed. The effects of expression host system choice on product molecular constraints, ease of processing, and flowsheet design and scale-up are compared. It is concluded that there is no unique host system that can consistently yield high expression levels for a wide range of single chain antibodies; instead, product sequence and end application often dictate the optimum choice of expression host. Irrespective of host systems, adequate a priori design and engineering of the molecular construct supported by good biophysical understanding of the single chain fragment molecules, is a crucial pre-requisite for improved product stability and downstream recovery, which will favourably impact final product yield and functionality.  相似文献   
289.
290.
Demand for plant-based meat alternatives has increased in recent years due to concerns about health, ethics, the environment, and animal welfare. Nevertheless, the market share of plant-based meat alternatives must increase significantly if they are to support sustainable food production and consumption. Flavor is an important limiting factor of the acceptability and marketability of plant-based meat alternatives. Undesirable chemosensory perceptions, such as a beany flavor, bitter taste, and astringency, are often associated with plant proteins and products that use them. This study reviewed 276 articles to answer the following five research questions: (1) What are the volatile and nonvolatile compounds responsible for off-flavors? (2) What are the mechanisms by which these flavor compounds are generated? (3) What is the influence of thermal extrusion cooking (the primary structuring technique to transform plant proteins into fibrous products that resemble meat in texture) on the flavor characteristics of plant proteins? (4) What techniques are used in measuring the flavor properties of plant-based proteins and products? (5) What strategies can be used to reduce off-flavors and improve the sensory appeal of plant-based meat alternatives? This article comprehensively discusses, for the first time, the flavor issues of plant-based meat alternatives and the technologies available to improve flavor and, ultimately, acceptability.  相似文献   
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