Enhancement of the Electrochemical Performance of SWCNT dispersed in a Silica Sol-gel Matrix by Reactive Insertion of a Conducting Polymer

The electroassisted encapsulation of Single-Walled Carbon Nanotubes was performed into silica matrices (SWCNT@SiO2). This material was used as the host for the potentiostatic growth of polyaniline (PANI) to yield a hybrid nanocomposite electrode, which was then characterized by both electrochemical and imaging techniques. The electrochemical properties of the SWCNT@SiO2-PANI composite material were tested against inorganic (Fe3+/Fe2+) and organic (dopamine) redox probes. It was observed that the electron transfer constants for the electrochemical reactions increased significantly when a dispersion of either SWCNT or PANI was carried out inside of the SiO2 matrix. However, the best results were obtained when polyaniline was grown through the pores of the SWCNT@SiO2 material. The enhanced reversibility of the redox reactions was ascribed to the synergy between the two electrocatalytic components (SWCNTs and PANI) of the composite material.

Proximodistal identity during vertebrate limb regeneration is regulated by Meis homeodomain proteins

The mechanisms by which cells obtain instructions to precisely re-create the missing parts of an organ remain an unresolved question in regenerative biology. Urodele limb regeneration is a powerful model in which to study these mechanisms. Following limb amputation, blastema cells interpret the proximal-most positional identity in the stump to reproduce missing parts faithfully. Classical experiments showed the ability of retinoic acid (RA) to proximalize blastema positional values. Meis homeobox genes are involved in RA-dependent specification of proximal cell identity during limb development. To understand the molecular basis for specifying proximal positional identities during regeneration, we isolated the axolotl Meis homeobox family. Axolotl Meis genes are RA-regulated during both regeneration and embryonic limb development. During limb regeneration, Meis overexpression relocates distal blastema cells to more proximal locations, whereas Meis knockdown inhibits RA proximalization of limb blastemas. Meis genes are thus crucial targets of RA proximalizing activity on blastema cells.

A study of matrix analysis methods for inelastic structures. Project no. 1467, Task no. 146701, prepared under Contract no. AF 33 (657)-8717 by Massachusetts Institute of Technology, Aeroelastic and Structures Research Laboratory.

Cover title.

Observations in surgery : being a collection of one hundred and twenty eight different cases : with particular remarks on each, for the improvement of young students : wherein not only the method of practice in difficult labours, but other distempers incident to the female sex are copiuosly enlarged on : among others that of the descent of the womb, clearly proving the reality of such a disease in opposition to Mr. Veduc : to which are added the particular receipts of such remedies as were used by the author in each case /

Mode of access: Internet.

The identity of the old Hartford Convention Federalists with the modern Whig, Harrison Party. Carefully illustrated by living specimens, and dedicated to the young men of the Union.

Note of explanation at end signed by Charles G. Greene and B. F. Hallett, Boston, Aug. 1840.

The history of ancient America, anterior to the time of Columbus; proving the identity of the aborigines with the Tyrians and Israelites; and the introduction of Christianity into the western hemisphere by the apostle St. Thomas.

Added t.p., engr.: An original history of ancient America. Founded upon the ruins of antiquity ...

Debrett's baronetage of England : containing their descent and present state, their collateral branches, births, marriages, and issue, from the institution of the order in 1611... / by John Debrett.

Mode of access: Internet.

Breaking the wilderness; The story of the conquest of the far West, from the wanderings of Cabeza de Vaca, to the first descent of the Colorado by Powell, and the completion of the Union Pacific railway, with particular account of the exploits of trappers and traders, by Frederick S. Dellenbaugh...

Mode of access: Internet.

Homo versus Darwin: a judicial examination of statements recently published by Mr. Darwin regarding "The descent of man" ...

Mode of access: Internet.

Interrogation of Gender Identity: Aesthetic Consumption of Korean Television Dramas by Young Women in China

Given the popularity of Korean television dramas among various age groups in other countries, one would expect to see a similar pattern of consumption across different ages in China. Instead, we see high levels of consumption of Korean dramas by a very specific demographic. Why do young Chinese females consume Korean dramas at such high levels? I argue that young Chinese women’s heavy consumption of Korean dramas that portray a particular aesthetic of self and familial resolution may be explained by a need to redress contemporary psychological issues related to gendered self-identity. I posit that the identity formation processes of this particular demographic has been shaped by changes in family dynamics that stem from social and political restructuring in the 1980s, particularly the one-child policy. Thus, this thesis explores how the consumption of Korean dramas by young females in China may be understood as an implicit interrogation of gendered identity.

Development and transplantation of a mineralized matrix formed by osteoblasts in vitro for bone regeneration

The use of extracellular matrix materials as scaffolds for the repair and regeneration of tissues is receiving increased attention. The current study was undertaken to test whether extracellular matrix formed by osteoblasts in vitro could be used as a scaffold for osteoblast transplantation and induce new bone formation in critical size osseous defects in vivo. Human osteoblasts derived from alveolar bone were cultured in six-well plates until confluent and then in mineralization media for a further period of 3 weeks to form an osteoblast-mineralized matrix complex. Histologically, at this time point a tissue structure with a connective tissue-like morphology was formed. Type I collagen was the major extracellular component present and appeared to determine the matrix macrostructure. Other bone-related proteins such as alkaline phosphatase (ALP), bone morphogenetic protein (BMP)-2 and -4, bone sialoprotein (BSP), osteopontin (OPN), and osteocalcin (OCN) also accumulated in the matrix. The osteoblasts embedded in this matrix expressed mRNAs for these bone-related proteins very strongly. Nodules of calcification were detected in the matrix and there was a correlation between calcification and the distribution of BSP and OPN. When this matrix was transplanted into a critical size bone defect in skulls of inummodeficient mice (SCID), new bone formation occurred. Furthermore, the cells inside the matrix survived and proliferated in the recipient sites, and were traceable by the human-specific Alu gene sequence using in situ hybridization. It was found that bone-forming cells differentiated from both transplanted human osteoblasts and activated endogenous mesenchymal cells. This study indicates that a mineralized matrix, formed by human osteoblasts in vitro, can be used as a scaffold for osteoblast transplantation, which subsequently can induce new bone formation.

Peptide quantification by matrix-assisted laser desorption ionisation time-of-flight mass spectrometry: Investigations of the cyclotide kalata B1 in biological fluids

A rapid method has been developed for the quantification of the prototypic cyclotide kalata B I in water and plasma utilizing matrix-assisted laser desorption ionisation time-of-flight (MALDI-TOF) mass spectrometry. The unusual structure of the cyclotides means that they do not ionise as readily as linear peptides and as a result of their low ionisation efficiency, traditional LC/MS analyses were not able to reach the levels of detection required for the quantification of cyclotides in plasma for pharmacokinetic studies. MALDI-TOF-MS analysis showed linearity (R-2 > 0.99) in the concentration range 0.05-10 mu g/mL with a limit of detection of 0.05 mu g/mL (9 fmol) in plasma. This paper highlights the applicability of MALDI-TOF mass spectrometry for the rapid and sensitive quantification of peptides in biological samples without the need for extensive extraction procedures. (c) 2005 Elsevier B.V. All rights reserved.