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Samples of highly enriched semiconducting SWCNTs with average diameters of 1.35 nm have been prepared by combining PODOF polymer wrapping with size-exclusion chromatography. The purity of the material was determined to be >99.7% from the transfer characteristics of short-channel transistors comprising densely aligned sc-SWCNTs. The transistors have a hole mobility of up to 297 cm(2)V(-1) s(-1) and an On/Off ratio as high as 2 × 10(8).

High affinity DNA aptamers against C-reactive protein (CRP) were obtained using a microfluidic chip. The aptamers were then used for the construction of an Au nanoparticle enhanced surface plasmon resonance biosensor, which was introduced for the detection of CRP at concentrations ranging from 10 pM to 100 nM in diluted human serum.

An idea drug carrier, with good binding affinity, selectivity, drug payload capacity, and cellular internalized capability, will greatly improve the efficiency of target delivery. Herein a self-assembled and multivalent DNA nanostructure was developed as drug carrier for efficient and targeted delivery. The DNA structure was similar to that of a centipede, composed of trunk and legs: The trunk was a self-assembled DNA scaffold via hybridization chain reaction (HCR) from two biotinylated hairpin monomers created upon initiation by a trigger DNA, and the legs were biotinylated aptamers conjugated to the trunk via streptavidin-biotin affinity interaction. The long trunk of the "DNA nanocentipede" was loaded with doxorubicin (Dox), and the legs were SMMC-7721 cell-binding aptamers (Zy1) which functioned as targeting moieties to firmly and selectively grasp target cells. The results of agarose gel electrophoresis and fluorescence anisotropy confirmed that Zy1-based DNA nanocentipedes (Zy1-Nces) were successfully constructed. Flow cytometric analyses demonstrated that Zy1-Nces were more effective than free Zy1 in binding affinity and selectivity due to a multivalent effect. Confocal microscopy studies demonstrated that the internalization was highly dependent on the higher valences of DNA nanocentipedes without the loss of selectivity. Meanwhile, Zy1-Nces exhibited high drug-loading capacity and selective drug transport. The results of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed enhanced cellular cytotoxicity of the Dox-loaded Zy1-Nces (Zy1-Nces-Dox) to the target SMMC-7721 cells but not negative control L02 cells. This approach is applicable to prepare drug carriers for other targets by construction of the nanocentipedes with relevant nucleic acid fragments.

BackgroundTraumatic brain injury (TBI) survivors often report difficulties with understanding and producing paralinguistic cues, as well as understanding and producing basic communication tasks. However, a large range of communicative deficits in this population cannot be adequately explained by linguistic impairment. The review examines prosodic processing performance post-TBI, its relationship with injury severity, brain injury localization, recovery and co-occurring psychiatric or mental health issues post-TBIMethodsA systematic review using several databases including MEDLINE, EMBASE, Cochrane, LLBA (Linguistics and Language Behaviour Abstract) and Web of Science (January 1980 to May 2015), as well as a manual search of the cited references of the selected articles and the search cited features of PubMed was performed. The search was limited to comparative analyses between individuals who had a TBI and non-injured individuals (control). The review included studies assessing prosodic processing outcomes after TBI has been formally diagnosed. Articles that measured communication disorders, prosodic impairments, aphasia, and recognition of various aspects of prosody were included. Methods of summary included study characteristics, sample characteristics, demographics, auditory processing task, age at injury, brain localization of the injury, time elapsed since TBI, reports between TBI and mental health, socialization and employment difficulties. There were no limitations to the population size, age or gender. Results were reported according to the PRISMA guidelines. Two raters evaluated the quality of the articles in the search, extracted data using data abstraction forms and assessed the external and internal validity of the studies included using STROBE criteria. Agreement between the two raters was very high (Cohen’s kappa = .89, P < 0.001). Results are reported according to the PRISMA guidelines.ResultsA systematic review of 5212 records between 1980 and 2015 revealed 206 potentially eligible studies and 8 case-control studies (3 perspective and 5 retrospective) met inclusion and exclusion criteria for content and quality. Performance on prosodic processing tasks was found to be impaired among all participants with a history of TBI (ages ranged from 8 to 70 years old), compared to those with no history of TBI, in all eight studies examined. Compared with controls, individuals with a history of TBI had statistically significantly slower reaction time in identifying emotions from prosody and impaired processing of prosodic information that is muffled, non-sense, competing, or in conflict (prosody versus semantics). Heterogeneous findings on correlations between specific brain locations and prosodic processing impairment were reported. Psychiatric issues, employment status or social integration post-TBI were scarcely reported but, when reported, they co-occurred with a history of TBI and prosodic impairments.ConclusionsThe current review confirms the relationship between impaired prosodic processing and history...

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Ultrahigh purity semiconducting single-walled carbon nanotubes (S-SWCNTs) are required for high-performance transistors. Aqueous two-phase (ATP) separation is an attractive method to obtain such SWCNTs due to its simplicity and scalability. This work targeted two questions; namely what is the upper limit of S-SWCNT purity that can be achieved by multiple cycles of ATP separation from the most commonly used polyethylene glycol and dextran system and how accurately can commonly used methods characterize the improvement in purity? SWCNT purity in nanotube dispersions obtained by multi-cycle ATP separation (2, 4, 6 and 8 cycles) was evaluated by three methods, including UV-vis-NIR absorption spectroscopy analysis, performance of thin-film field effect transistors (FETs) prepared by drop casting and short-channel FET devices prepared by dielectrophoresis deposition. Absorption spectroscopic analysis and the performance of the thin-film FET devices can hardly differentiate metallic SWCNT residues in the dispersions obtained after 4 cycles with the purity above 99.5%, and the short channel FET devices prepared by dielectrophoresis deposition are more sensitive towards tiny metallic SWCNT residues. A new method was also demonstrated to visualize the minor metallic content in the nanotube suspension using voltage contrast imaging in a scanning electron microscope, which enables rapid screening of many devices and the accurate obtainment of metallic content without performing a large number of individual transconductance measurements.

The Khondalite Belt within the Inner Mongolia Suture Zone (IMSZ) in the North China Craton is a classic example for Paleoproterozoic ultrahigh-temperature (UHT) metamorphism. Here we report new spinel-bearing metapelitic granulites from a new locality at Xumayao within the southern domain of the IMSZ. Petrological studies and thermodynamic modeling of the spinel þ quartz-bearing assemblage shows that these rocks experienced extreme metamorphism at UHT conditions. Spinel occurs in two textural settings: 1) high X Zn (Zn/(Mg þ Fe II þ Zn) Z 0.071e0.232) spinel with perthitic K-feldspar, sillimanite and quartz in the rock matrix; and 2) low X Zn (0.045e0.070) spinel as inclusions within garnet porphyroblasts in association with quartz and sillimanite.Our phase equilibria modeling indicates two main stages during the metamorphic evolution of these rocks: 1) near-isobaric cooling from 975 C to 875 C around 8 kbar, represented by the formation of * Corresponding author. Tel.: þ86 15120092441 (mobile). GEOSCIENCE FRONTIERSjournal homepage: www.elsevier.com/locate/gsf GEOSCIENCE FRONTIERS 3(5) (2012) 603e611 garnet porphyroblasts from spinel and quartz; and 2) cooling and decompression from 850 C, 8 kbar to below 750 C, 6.5 kbar, represented by the break-down of garnet. The spinel þ quartz assemblage is considered to have been stable at peak metamorphism, formed through the break-down of cordierite, indicating a near isothermal compression process. Our study confirms the regional extent of UHT metamorphism within the IMSZ associated with the Paleoproterozoic subduction-collision process. ª 2012, China University of Geosciences (Beijing) and Peking University. Production and hosting by Elsevier B.V. All rights reserved.