Liquid crystals {(LCs)} are used extensively by the electronics industry as display devices. Advances in the understanding of the liquid crystalline phase and the chemistry therein lead to the development of {LC} exhibiting faster switching speed with greater twist angle. This in turn lead to the emergence of liquid crystal displays, rendering dial-and-needle based displays (such as those used in various meters) and cathode ray tubes obsolete. In this article, we review the history of {LC} and their emergence as an invaluable material for display devices and the more recent discovery of their use as sensing elements in biosensors. This new application of {LC} as tools in the development of fast and simple biosensors is envisaged to gain more importance in the foreseeable future.

The surface modification of iron oxide magnetic nanoparticles {(MNPs)} with gum Arabic {(GA)} via adsorption and covalent coupling was studied. The adsorption of {GA} was assessed during {MNP} chemical synthesis by the co-precipitation method {(MNP\_GA)}, and after {MNP} synthesis on both bare magnetite and {MNP\_GA.} The covalent immobilization of {GA} at the surface of aldehyde-activated {(MNP\_GAAPTES)} or aminated {MNPs} {(MNP\_GAEDC)} was achieved through free terminal amino and carboxylate groups from {GA.} The presence of {GA} at the surface of the {MNPs} was confirmed by {FTIR} and by the quantification of {GA} by the bicinchoninic acid test. Results indicated that the maximum of {GA} coating was obtained for the covalent coupling of {GA} through its free carboxylate groups {(MNP\_GAEDC)}, yielding a maximum of 1.8&\#xa0;g of {GA} bound/g of dried particles. The hydrodynamic diameter of {MNPs} modified with {GA} after synthesis resulted in the lowest values, in opposition to the {MNPs} co-precipitated with {GA} which presented the tendency to form larger aggregates of up to 1&\#xa0;μm. The zeta potentials indicate the existence of negatively charged surfaces before and after {GA} coating. The potential of the {GA} coated {MNPs} for further biomolecule attachment was assessed through anchorage of a model antibody to aldehyde-functionalized {MNP\_GA} and its subsequent detection with an {FITC} labeled anti-antibody.

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Some results presented in the paper ?Modeling fractional stochastic systems as non-random fractional dynamics driven Brownian motions? ?I. Podlubny, Fractional Differential Equations, Academic Press, San Diego, 1999? are discussed in this paper. The slightly modified Grünwald-Letnikov derivative proposed there is used to deduce some interesting results that are in contradiction with those proposed in the referred paper. Keywords: Fractional calculus; Grünwald-Letnikov derivative; Fractional Brownian motion

Wound healing is a complex process involving an integrated response by many different cell types and growth factors in order to achieve rapid restoration of skin architecture and function. The present study evaluated the applicability of a chitosan hydrogel (CH) as a wound dressing. Scanning electron microscopy analysis was used to characterize CH morphology. Fibroblast cells isolated from rat skin were used to assess the cytotoxicity of the hydrogel. CH was able to promote cell adhesion and proliferation. Cell viability studies showed that the hydrogel and its degradation by-products are noncytotoxic. The evaluation of the applicability of CH in the treatment of dermal burns in Wistar rats was performed by induction of full-thickness transcutaneous dermal wounds. Wound healing was monitored through macroscopic and histological analysis. From macroscopic analysis, the wound beds of the animals treated with CH were considerably smaller than those of the controls. Histological analysis revealed lack of a reactive or a granulomatous inflammatory reaction in skin lesions with CH and the absence of pathological abnormalities in the organs obtained by necropsy, which supported the local and systemic histocompatibility of the biomaterial. The present results suggest that this biomaterial may aid the re-establishment of skin architecture.

Electrospun cellulose-based nano and microfibers and a nematic liquid crystal are used to assemble an electro-optical (EO) light-scattering device that shows enhanced characteristics when compared to similar devices. Based on the controlled scattering of light in the composite system, the device can achieve light transmission coefficients tunable from 1% up to around 89%. Simulation of the EO behavior indicates that the roughness of the polymer-liquid crystal interface is crucial for the optical performance of the device.

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BACKGROUND:
The unique responsiveness of Vgamma9Vdelta2 T-cells, the major gammadelta subset of human peripheral blood, to non-peptidic prenyl pyrophosphate antigens constitutes the basis of current gammadelta T-cell-based cancer immunotherapy strategies. However, the molecular mechanisms responsible for phosphoantigen-mediated activation of human gammadelta T-cells remain unclear. In particular, previous reports have described a very slow kinetics of activation of T-cell receptor (TCR)-associated signal transduction pathways by isopentenyl pyrophosphate and bromohydrin pyrophosphate, seemingly incompatible with direct binding of these antigens to the Vgamma9Vdelta2 TCR. Here we have studied the most potent natural phosphoantigen yet identified, (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMB-PP), produced by Eubacteria and Protozoa, and examined its gammadelta T-cell activation and anti-tumor properties.
METHODOLOGY/PRINCIPAL FINDINGS:
We have performed a comparative study between HMB-PP and the anti-CD3epsilon monoclonal antibody OKT3, used as a reference inducer of bona fide TCR signaling, and followed multiple cellular and molecular gammadelta T-cell activation events. We show that HMB-PP activates MEK/Erk and PI-3K/Akt pathways as rapidly as OKT3, and induces an almost identical transcriptional profile in Vgamma9(+) T-cells. Moreover, MEK/Erk and PI-3K/Akt activities are indispensable for the cellular effects of HMB-PP, including gammadelta T-cell activation, proliferation and anti-tumor cytotoxicity, which are also abolished upon antibody blockade of the Vgamma9(+) TCR Surprisingly, HMB-PP treatment does not induce down-modulation of surface TCR levels, and thereby sustains gammadelta T-cell activation upon re-stimulation. This ultimately translates in potent human gammadelta T-cell anti-tumor function both in vitro and in vivo upon transplantation of human leukemia cells into lymphopenic mice,
CONCLUSIONS/SIGNIFICANCE:
The development of efficient cancer immunotherapy strategies critically depends on our capacity to maximize anti-tumor effector T-cell responses. By characterizing the intracellular mechanisms of HMB-PP-mediated activation of the highly cytotoxic Vgamma9(+) T-cell subset, our data strongly support the usage of this microbial antigen in novel cancer clinical trials.

Drug Discovery in modern times straddles three main periods. The first notable period can be traced to the nineteenth century where the basis of drug discovery relied on the serendipity of the medicinal chemists. The second period commenced around the early twentieth century when new drug structures were found, which contributed for a new era of antibiotics discovery. Based on these known structures, and with the development of powerful new techniques such as molecular modelling, combinatorial chemistry, and automated high-throughput screening, rapid advances occurred in drug discovery towards the end of the century. The period also was revolutionized by the emergence of recombinant DNA technology, where it became possible to develop potential drugs target candidates. With all the expansion of new technologies and the onset of the "Omics" revolution in the twenty-first century, the third period has kick-started with an increase in biopharmaceutical drugs approved by FDA/EMEA for therapeutic use.

BACKGROUND:
Plasmodium sporozoites migrate to the liver where they traverse several hepatocytes before invading the one inside which they will develop and multiply into thousands of merozoites. Although this constitutes an essential step of malaria infection, the requirements of Plasmodium parasites in liver cells and how they use the host cell for their own survival and development are poorly understood.
RESULTS:
To gain new insights into the molecular host-parasite interactions that take place during malaria liver infection, we have used high-throughput microarray technology to determine the transcriptional profile of P. berghei-infected hepatoma cells. The data analysis shows differential expression patterns for 1064 host genes starting at 6 h and up to 24 h post infection, with the largest proportion correlating specifically with the early stages of the infection process. A considerable proportion of those genes were also found to be modulated in liver cells collected from P. yoelii-infected mice 24 and 40 h after infection, strengthening the data obtained with the in vitro model and highlighting genes and pathways involved in the host response to rodent Plasmodium parasites.
CONCLUSION:
Our data reveal that host cell infection by Plasmodium sporozoites leads to a coordinated and sequential set of biological events, ranging from the initial stage of stress response up to the engagement of host metabolic processes and the maintenance of cell viability throughout infection.

We show that suspended nano and microfibres electrospun from liquid crystalline cellulosic solutions will curl into spirals if they are supported at just one end, or, if they are supported at both ends, will twist into a helix of one handedness over half of its length and of the opposite handedness over the other half, the two halves being connected by a short straight section. This latter phenomenon, known as perversion, is a consequence of the intrinsic curvature of the fibres and of a topological conservation law. Furthermore, agreement between theory and experiment can only be achieved if account is taken of the intrinsic torsion of the fibres. Precisely the same behaviour is known to be exhibited by the tendrils of climbing plants such as Passiflora edulis, albeit on a lengthscale of millimetres, i.e., three to four orders of magnitude larger than in our fibres. This suggests that the same basic, coarse-grained physical model is applicable across a range of lengthscales.

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The successful development of autonomous mobile robot assistants depends significantly on the well-balanced reconcilements of the technically possible and the socially desirable. Based on empirical research 2 substantiated conclusions can be established for the suitability of "scenario-based design" (Rosson/Carroll 2003) for the successful development of mobile robot assistants and automated guided vehicles to be applied for service functions in stationary care facilities for seniors.

No abstract included.

Lactoperoxidase (LPO) is a structurally complex and stable mammalian redox enzyme. Here we aim at evaluating the influence of ionic interactions and how these intertwine with the structural dynamics, stability and activity of LPO. In this respect, we have compared LPO guanidinium hydrochloride (GdmCl) and urea denaturation pathways and performed a detailed investigation on the effects of pH on the LPO conformational dynamics and stability. Our experimental findings using far-UV CD, Trp fluorescence emission and ESR spectroscopies clearly indicate that LPO charged-denaturation with GdmCl induced a sharp two-step process versus a three-step unfolding mechanism induced by urea. This differential effect between GdmCl and urea suggests that ionic interactions must play a rather prominent role in the stabilization of LPO. With both denaturants, the protein core was shown to retain activity up to near the respective Cm values. Moreover, a pH titration of LPO evidenced no significant conformational alterations or perturbation of heme activity within the 4 to 11 pH interval. In contrast, alterations of ionic interactions by poising LPO at pH 3, 2 and 12 resulted in a loss of secondary structure, loosening of tertiary contacts and loss of activity, which appear to be associated with the perturbation of the hydrophobic core, as evidenced by ANS binding, as well as disruption of the heme pocket demonstrated by optical and EPR spectroscopies. Overall, LPO is characterised by a high degree of peripheral structural plasticity without perturbation of the core heme moiety. The possible physiological meaning of such features is discussed.

The project started in 2009 with the support of DAAD in Germany and CRUP in Portugal under the “Collaborative German-Portuguese University Actions” programme. One central goal is the further development of a theory of technology assessment applied to robotics and autonomous systems in general that reflects in its methodology the changing conditions of knowledge production in modern societies and the emergence of new robotic technologies and of associated disruptive changes. Relevant topics here are handling broadened future horizons and new clusters of science and technology (medicine, engineering, interfaces, industrial automation, micro-devices, security and safety), as well as new governance structures in policy decision making concerning research and development (R&D).

The project started in 2009 with the support of DAAD in Germany and CRUP in Portugal under the “Collaborative German-Portuguese University Actions” programme. One central goal is the further development of a theory of technology assessment applied to robotics and autonomous systems in general that reflects in its methodology the changing conditions of knowledge production in modern societies and the emergence of new robotic technologies and of associated disruptive changes. Relevant topics here are handling broadened future horizons and new clusters of science and technology (medicine, engineering, interfaces, industrial automation, micro-devices, security and safety), as well as new governance structures in policy decision making concerning research and development (R&D).