Plasmon-enhanced two-photon-induced isomerization for highly-localized light-based actuation of inorganic/organic interfaces

Two-photon initiated photo-isomerization of an azobenzene moiety adsorbed on silver nanoparticles (Ag NPs) is demonstrated. The azobenzene is linked to a materials-binding peptide that brings it into intimate contact with the Ag NP surface, producing a dramatic enhancement of its two-photon absorbance. An integrated modeling approach, combining advanced conformational sampling with Quantum Mechanics/Capacitance Molecular Mechanics and response theory, shows that charge transfer and image charges in the Ag NP generate local fields that enhance two-photon absorption of the cis isomer, but not the trans isomer, of adsorbed molecules. Moreover, dramatic local field enhancement is expected near the localized surface plasmon resonance (LSPR) wavelength, and the LSPR band of the Ag NPs overlaps the azobenzene absorbance that triggers cis to trans switching. As a result, the Ag NPs enable two-photon initiated cis to trans isomerization, but not trans to cis isomerization. Confocal anti-Stokes fluorescence imaging shows that this effect is not due to local heating, while the quadratic dependence of switching rate on laser intensity is consistent with a two-photon process. Highly localized two-photon initiated switching could allow local manipulation near the focal point of a laser within a 3D nanoparticle assembly, which cannot be achieved using linear optical processes.

Two-photon endomicroscopy for 3D imaging of cancer cells labelled with gold nanorods

Biofunctional nanorods are developed to specifically target cancer cells. The cervical cancer cells, HeLa cells, are labeled by these biofunctional gold nanorods. Those cancer cells can be detected by a multi-photon-excited photoluminescence endomicroscope, which proves that the cancers can be in vivo diagnosed by using biofunctional gold nanorods with nonlinear endomicroscopy.

Two-photon imaging and photothermal therapy of cancer cells using biofunctional gold nanorods

Transferrin-conjugated gold nanorods were used for targeting, two-photon imaging and photothermal therapy of cancer cells. The presence of nanorods significantly reduced the laser power effective for therapy.

Graphene oxide nanoparticles as a nonbleaching optical probe for two-photon luminescence imaging and cell therapy

Lasting glow: Under femtosecond laser irradiation, graphene oxide nanoparticles (GONs) give strong two-photon luminescence (TPL; see picture). The presence of GONs also induces microbubbling, which causes cell death at an order of magnitude lower laser power than when cells are not labeled. The results show that GONs can be used for TPL-based imaging and photothermal cancer therapy.

Child maltreatment, family characteristics and adult adjustment: mediating and moderating processes

Two alternate processes that may explain the relationship between child maltreatment, childhood family characteristics and adult adjustment (mediation and moderation) were tested using retrospective data from a community sample (N = 175). The levels of five different types of child maltreatment did not mediate the relationship between childhood family variables and adult adjustment. In contrast, family background played a mediating role in the relationship between maltreatment and adjustment. Evidence of moderation was found in the interactions between different maltreatment types in predicting adjustment. Partial support was found for the moderating influence of family factors on the relationship of maltreatment to adjustment.

A two-stage dynamic group decision making method for processing ordinal information

In group decision making (GDM) problems, ordinal data provide a convenient way of articulating preferences from decision makers (DMs). A number of GDM models have been proposed to aggregate such kind of preferences in the literature. However, most of the GDM models that handle ordinal preferences suffer from two drawbacks: (1) it is difficult for the GDM models to manage conflicting opinions, especially with a large number of DMs; and (2) the relationships between the preferences provided by the DMs are neglected, and all DMs are assumed to be of equal importance, therefore causing the aggregated collective preference not an ideal representative of the group's decision. In order to overcome these problems, a two-stage dynamic group decision making method for aggregating ordinal preferences is proposed in this paper. The method consists of two main processes: (i) a data cleansing process, which aims to reduce the influence of conflicting opinions pertaining to the collective decision prior to the aggregation process; as such an effective solution for undertaking large-scale GDM problems is formulated; and (ii) a support degree oriented consensus-reaching process, where the collective preference is aggregated by using the Power Average (PA) operator; as such, the relationships of the arguments being aggregated are taken into consideration (i.e., allowing the values being aggregated to support each other). A new support function for the PA operator to deal with ordinal information is defined based on the dominance-based rough set approach. The proposed GDM model is compared with the models presented by Herrera-Viedma et al. An application related to controlling the degradation of the hydrographic basin of a river in Brazil is evaluated. The results demonstrate the usefulness of the proposed method in handling GDM problems with ordinal information.

Manufacturing influence on the delamination fracture behavior of the T800H/3900-2 carbon fiber reinforced polymer composites

'Torayca' T800H/3900-2 is the first material qualified on Boeing Material Specification (BMS 8-276) which utilizes the thermoplastic-particulate interlayer toughening technology. Two manufacturing processes, the autoclave process and the fast heating rated Quickstep™ process, were employed to cure this material. The Quickstep process is a unique composite production technology which utilizes the fast heat transfer rate of fluid to heat and cure polymer composite components. The manufacturing influence on the mode I delamination fracture toughness of laminates was investigated by performing double cantilever beam tests. The composite specimens fabricated by two processes exhibited dissimilar delamination resistance curves (R-curves) under mode I loading. The initial value of fracture toughness GIC-INIT was 564 J/m2 for the autoclave specimens and 527 J/m2 for the Quickstep specimens. However, the average propagation fracture toughness GIC-PROP was 783 J/m2 for the Quickstep specimens, which was 2.6 times of that for the autoclave specimens. The mechanism of fracture occurred during delamination was studied under scanning electron microscope (SEM). Three types of fracture were observed: the interlayer fracture, the interface fracture, and the intralaminar fracture. These three types of fracture played different roles in affecting the delamination resistance curves during the crack growth. More fiber bridging was found in the process of delamination for the Quickstep specimens. Better fiber/matrix adhesion was found in the Quickstep specimens by conducting indentation-debond tests.

The struggle for the body, mind and soul of AFL footballers

"The book discusses the profound, often troubling, always complex struggles for the body, mind and soul of elite performers in contemporary sports entertainment environments. This struggle is shaped by two powerful processes. On the one hand we witness the translation and application of a range of rationalities and knowledges from fields such as psychology, sport science and medicine, dietetics, education and management. All of which have the consequence of subjecting elite performers to often intrusive regimes of measurement, testing, medical intervention, surveillance, education and regulation in the pursuit of performance and success. At the same time we can identify ways in which the commodification of sports/games, the drive to develop and grow as a sports entertainment business and the pursuit and maintenance of a media presence and profile on which brand relationships can be established and grown has the consequence of transforming elite performers into highly paid sports celebrities whose image, persona and brand is positioned in a crowded, highly competitive marketplace to be scrutinised, judged and consumed.
[The] struggle that takes on new dimensions in the evolution of sports/games into global sports entertainment industries and businesses....The book reveals new insights into the tensions that emerge between different levels of the AFL sports entertainment industry about what it means to be a professional footballer at the start of the 21st century. The book analyses aspects of this struggle for the body, mind and soul at different stages in a playing career."--Media release.

Building social capital in groups : facilitating skill development for natural resource management

Analysis of the experiences of four farmer groups set up to learn how to jointly manage local natural resource issues shows that the groups are going though two simultaneous processes. One builds technical competency in natural resource management and the other is the underpinning social process that allows the groups to make decisions and work collectively, which builds social capital. Natural resource management practitioners and farmers are practical people. They are likely to be more comfortable with a process that develops monitoring tools and benchmarks for natural resource management than a process of group development and social capital formation. Yet the two are intrinsically linked. This paper reflects on and analyses the experience of establishing and working with farmer groups as they go through a process of identifying environmental issues, setting and monitoring environmental benchmarks and identifying and implementing sustainable farming practices to meet the benchmarks.

Two questions emerged from the analysis. First, how do the four groups compare to other measures of effective natural resource management groups? Second, what are the characteristics of the groups that make them more or less effective and what has occurred in the groups (either before or during this project) to make them more or less effective? Social capital emerges as a key determinant of group effectiveness. Social capital is most effective when it comprises a balance of bonding and bridging networks, and includes shared values in relation to the purpose of the group.

Policy makers and extension workers need to understand the link between the two simultaneous processes occurring as people come together in groups to define and implement best practice at a local level, and how to use knowledge of social processes when designing the more concrete process of developing and implementing best practice monitoring and benchmarking with groups. An understanding of how people build social capital as they work in groups will assist with designing and facilitating group projects in a range of contexts, not only natural resource management.

One-dimensional growth of TiO2 nanorods from ilmenite sands

Growth mechanisms of TiO₂ nanorods synthesized from mineral ilmenite using ball milling and annealing method have been systematically investigated. Two annealing processes are needed to grow the nanorods. The heating rate and gaseous environment in the first annealing step are critical to the formation of intermediate phases; these and the annealing atmosphere in the second heating play very important roles in nanorod growth. One-dimensional growth of the nanorods induced by low-temperature annealing in nitrogen plus hydrogen is possibly driven by atom vacancy diffusion in addition to surface diffusion.

Cancer-cell microsurgery using nonlinear optical endomicroscopy

Near-infrared laser-based microsurgery is promising for noninvasive cancer treatment. To make it a safe technique, a therapeutic process should be controllable and energy efficient, which requires the cancer cells to be identifiable and observable. In this work, for the first time we use a miniaturized nonlinear optical endomicroscope to achieve microtreatment of cancer cells labeled with gold nanorods. Due to the high two-photon-excited photoluminescence of gold nanorods, HeLa cells inside a tissue phantom up to 250 μm deep can be imaged by the nonlinear optical endomicroscope. This facilitates microsurgery of selected cancer cells by inducing instant damage through the necrosis process, or by stopping cell proliferation through the apoptosis process. The results indicate that a combination of nonlinear endomicroscopy with gold nanoparticles is potentially viable for minimally invasive cancer treatment.

Comparison of different extrusion methods for compaction of powders

Densification of metallic powders by means of extrusion is regarded as a very attractive processing technique that allows obtaining a high level of relative density of the compact. However, the uniformity of the relative density depends on that of strain distribution and on the processing parameters. Several variants of extrusion can be used for compaction of metal particulates, including the conventional extrusion (CE) and equal channel angular pressing (ECAP), often referred to as equal-channel angular extrusion. Each of these processes has certain advantages and drawbacks with respect to compaction. A comparative study of these two extrusion processes influencing the relative density of compacts has been conducted by numerical simulation using commercial finite element software DEFORM2D. The results have been validated by experiments with titanium and magnesium powders and chips.