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Summary The ever-increasing interest in nanostructured materials and shrinking dimensions of state-of-the-art devices pose new challenges both in synthesis and metrology. Although an extensive range of nanotubular materials of different compositions and for various applications are reported in the literature, often detailed structural characterisation of these materials is limited. This is due to the fact that techniques and characterisation protocols for structural analysis of 'buried' nano-scale features, defects or inhomogenities that are difficult to obtain by conventional imaging methods, are still not fully developed. In the case of 1D nanoporous structures, the continuity of the nano-tubular channels, their uniformity and orientation is of particular interest. Herein, we employ a serial sectioning technique on a dual beam FIB followed by 3D volume reconstruction for comprehensive analysis of tubular metal nanostructures encapsulated within porous anodic alumina. Using this technique, we demonstrate a nano-tomography characterisation protocol that can be used for analysis of nanoporous structures with emphasis on their channel uniformity and orientation. We demonstrate that high-resolution nano-tomography can be performed to visualise pores as small as 60 nm in diameter, with conical or globular shapes, and to quantitatively estimate their localisation and distribution along one-dimensional metal structures. We specifically chose to examine Cu-nanotubes, deposited electrochemically within anodic alumina template, because there is a great deal of debate regarding the deposition process. Hence, the comprehensive analysis shown here is not only demonstrating the applicability of the developed characterisation methodology but it is also, in conjunction with other advanced electron microscopy methods such as elemental nano-scale STEM/EDX mapping, providing conclusive evidence of the key factors at play during the deposition process. [ABSTRACT FROM AUTHOR]

Strychnine-sensitive glycine receptors mediate inhibitory neurotransmission occurring in the brain stem and spinal cord. Alcohols, volatile anesthetics and inhaled drugs of abuse are positive allosteric modulators of glycine receptor function, normally enhancing function only in the presence of glycine. A complication in studying allosteric actions on ligand-gated ion channels is in the dissection of their effects on neurotransmitter binding from their effects on channel opening. Mutation of an aspartate residue at position 97 to arginine in the glycine receptor α1 subunit simulated the effects of glycine binding, producing receptors that exhibited tonic channel opening in the absence of neurotransmitter; i.e. these receptors demonstrated a dissociation of channel opening from neurotransmitter binding. In these receptors, ethanol, enflurane, chloroform, halothane, 1,1,1-trichloroethane and toluene elicited inward currents in the absence of glycine. We previously identified mutations on ligand-gated ion channels that eliminate ethanol, anesthetic and inhalant actions (such as S2671 on α1 glycine receptors). The double mutant (D97R and S2671) receptors were both constitutively active and resistant to the enhancing effects of ethanol and enflurane. These data demonstrate that ethanol and volatile anesthetics can affect glycine receptor channel opening independently of their effects on enhancing neurotransmitter binding. [ABSTRACT FROM AUTHOR]

The dynamic characteristics of a discrete mode laser diode fabricated in the InGaAs/InP multiple quantum well material system and emitting single mode at λ ≃ 2.0 μm are reported. Results are presented on the electro‐optical bandwidth, direct modulation and gain switched performance. [ABSTRACT FROM AUTHOR]

The article presents a study on the use of Kuder Preference Record or Vocational Form C-H to forecast turnover in industrial plant and to test the effectiveness of the "interest test approach" to labor turnover issue. It states that persons applying for a hourly paid jobs at metal parts factory had been given the Kuder Preference Record before the study. It adds that an alternate technique would be method development for tenure prediction from Kuder sub-scores. Results show that sub-scores were correlated with tenure of the Kuder scales which gave evidence of a significant relationship with tenure.

An edge-coupled high-speed photodiode based on strained InGaAs quantum wells for detection at 2000nm is demonstrated. The fabricated device shows a leakage current as low as 120nA at -3V bias voltage and a responsivity of around 0.3A/W at 2000nm. The high-speed butterfly packaging of the device is presented which shows a 3dB bandwidth of more than 10GHz. The device shows similar highspeed performance at 1550nm. [ABSTRACT FROM AUTHOR]