Emanuele Ricca, Vincenza Calabrò, Stefano Curcio, Alessandra Basso, Lucia Gardossi and Gabriele Iorio
Article: Fructose Production by Inulinase Covalently Immobilized on Sepabeads in Batch and Fluidized Bed Bioreactor
Int. J. Mol. Sci. 2010, 11(3), 1180-1189; doi:10.3390/ijms11031180 - published online 19 March 2010
Show/Hide AbstractAbstract: The present work is an experimental study of the performance of a recently designed immobilized enzyme: inulinase from Aspergillus sp. covalently immobilized on Sepabeads. The aim of the work is to test the new biocatalyst in conditions of industrial interest and to assess the feasibility of the process in a fluidized bed bioreactor (FBBR). The catalyst was first tested in a batch reactor at standard conditions and in various sets of conditions of interest for the process. Once the response of the catalyst to different operating conditions was tested and the operational stability assessed, one of the sets of conditions tested in batch was chosen for tests in FBBR. Prior to reaction tests, preliminary fluidization tests were realized in order to define an operating range of admissible flow rates. As a result, the FBR was run at different feed flow rates in a closed cycle configuration and its performance was compared to that of the batch system. The FBBR proved to be performing and suitable for scale up to large fructose production.

Oktay Yildirim, Tian Gang, Sachin Kinge, David N. Reinhoudt, Dave H. Blank, Wilfred G. van der Wiel, Guus Rijnders and Jurriaan Huskens
Article: Monolayer-directed Assembly and Magnetic Properties of FePt Nanoparticles on Patterned Aluminum Oxide
Int. J. Mol. Sci. 2010, 11(3), 1162-1179; doi:10.3390/iijms11031162 - published online 19 March 2010
Show/Hide AbstractAbstract: FePt nanoparticles (NPs) were assembled on aluminum oxide substrates, and their ferromagnetic properties were studied before and after thermal annealing. For the first time, phosph(on)ates were used as an adsorbate to form self-assembled monolayers (SAMs) on alumina to direct the assembly of NPs onto the surface. The Al₂O₃ substrates were functionalized with aminobutylphosphonic acid (ABP) or phosphonoundecanoic acid (PNDA) SAMs or with poly(ethyleneimine) (PEI) as a reference. FePt NPs assembled on all of these monolayers, but much less on unmodified Al₂O₃, which shows that ligand exchange at the NPs is the most likely mechanism of attachment. Proper modification of the Al₂O₃ surface and controlling the immersion time of the modified Al₂O₃ substrates into the FePt NP solution resulted in FePt NPs assembly with controlled NP density. Alumina substrates were patterned by microcontact printing using aminobutylphosphonic acid as the ink, allowing local NP assembly. Thermal annealing under reducing conditions (96%N₂/4%H₂) led to a phase change of the FePt NPs from the disordered FCC phase to the ordered FCT phase. This resulted in ferromagnetic behavior at room temperature. Such a process can potentially be applied in the fabrication of spintronic devices.

Hai Jiang, Mao-Jun Zhang, Rui-Chun Liu, Xin-Ying Tian, Yi-Xin Gu and Jian-Zhong Zhang
Article: Characteristics of Lipo-Oligosaccharide Loci of Campylobacter jejuni Isolates Associated with Guillain-Barré Syndrome from Hebei, China
Int. J. Mol. Sci. 2010, 11(3), 1155-1161; doi:10.3390/ijms11031155 - published online 19 March 2010
Show/Hide AbstractAbstract: Ganglioside mimicry by C. jejuni lipo-oligosaccharides (LOS) could induce the production of autoantibodies against gangliosides and the development of Guillain-Barré syndrome (GBS). The LOS biosynthesis region exhibits significant variation with different strains. Using PCR amplifications of genes from published LOS loci and sequencing the LOS biosynthesis loci, the eight GBS-associated C. jejuni strains from HeBei could be classified into four classes. The expression of sialylated LOS structures (class A) or non-sialylated LOS structures(class F, H and P) in the C. jejuni LOS is considered to be two different factors for the induction of GBS.

Zu-Guo Yu, Xiao-Wen Zhan, Guo-Sheng Han, Roger W. Wang, Vo Anh and Ka Hou Chu
Article: Proper Distance Metrics for Phylogenetic Analysis Using Complete Genomes without Sequence Alignment
Int. J. Mol. Sci. 2010, 11(3), 1141-1154; doi:10.3390/ijms11031141 - published online 18 March 2010
Show/Hide AbstractAbstract: A shortcoming of most correlation distance methods based on the composition vectors without alignment developed for phylogenetic analysis using complete genomes is that the “distances” are not proper distance metrics in the strict mathematical sense. In this paper we propose two new correlation-related distance metrics to replace the old one in our dynamical language approach. Four genome datasets are employed to evaluate the effects of this replacement from a biological point of view. We find that the two proper distance metrics yield trees with the same or similar topologies as/to those using the old “distance” and agree with the tree of life based on 16S rRNA in a majority of the basic branches. Hence the two proper correlation-related distance metrics proposed here improve our dynamical language approach for phylogenetic analysis.

Anton du Plessis, Christien Strydom and Lourens Botha
Article: Comparative Study of the Dissociative Ionization of 1,1,1 Trichloroethane Using Nanosecond and Femtosecond Laser Pulses
Int. J. Mol. Sci. 2010, 11(3), 1114-1140; doi:10.3390/ijms11031114 - published online 17 March 2010
Show/Hide AbstractAbstract: Changes in the laser induced molecular dissociation of 1,1,1-trichloroethane (TCE) were studied using a range of intensities and standard laser wavelengths with nanosecond and femtosecond pulse durations. TCE contains C-H, C-C and C-Cl bonds and selective bond breakage of one or more of these bonds is of scientific interest. Using laser ionization time of flight mass spectrometry, it was found that considerable variation of fragment ion peak heights as well as changes in relative peak ratios is possible by varying the laser intensity (by attenuation), wavelength and pulse duration using standard laser sources. The nanosecond laser dissociation seems to occur via C-Cl bond breakage, with significant fragmentation and only a few large mass ion peaks observed. In contrast, femtosecond laser dissociative ionization results in many large mass ion peaks. Evidence is found for various competing dissociation and ionization pathways. Variation of the nanosecond laser intensity does not change the fragmentation pattern, while at high femtosecond intensities large changes are observed in relative ion peak sizes. The total ionization yield and fragmentation ratios are presented for a range of wavelengths and intensities, and compared to the changes observed due to a linear chirp variation.

Di Wei
Review: Dye Sensitized Solar Cells
Int. J. Mol. Sci. 2010, 11(3), 1103-1113; doi:10.3390/ijms11031103 - published online 16 March 2010
Show/Hide AbstractAbstract: Dye sensitized solar cell (DSSC) is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO₂, ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.