Wavelength tuning in GaAsAlGaAs quantum wells by InAs submonolayer insertion

Wavelength tuning of exciton emissions has been achieved simply by inserting an InAs submonolayer at the centre of GaAs quantum wells during molecular beam epitaxy growth. Photoluminescence measurements show that the emission energy can be effectively tuned from the quantum-well-determined energy down to less than the band gap of GaAs, depending on the well width as well as the InAs layer thickness. Using the effective-mass approximation, the tuning effect can be well predicted theoretically The results reported here may provide an alternative way to tune the wavelength in optoelectronic devices.

SYNTHESIS AND CRYSTAL-STRUCTURES OF THE BIMETALLIC RARE-EARTH COMPLEXES AND STUDIES ON INSERTION MECHANISM OF DIENES POLYMERIZATION

The deepening of the studies on essentials of rare earth coordination catalyst brings about more and more reports on model compounds as active centre of the catalyst. Among them the most significant researches are those with identification of the crystal structures of compounds.

Surface Reconstruction from Multiple Views using Rational B-Splines and Knot Insertion

A method for reconstruction of 3D rational B-spline surfaces from multiple views is proposed. Given corresponding features in multiple views, though not necessarily visible in all views, the surface is reconstructed. First 2D B-spline patches are fitted to each view. The 3D B-splines and projection matricies can then be extracted from the 2D B-splines using factorization methods. The surface fit is then further refined via an iterative procedure. Finally, a hierarchal fitting scheme is proposed to allow modeling of complex surfaces by means of knot insertion. Experiments with real imagery demonstrate the efficacy of the approach.

Insertion of metal oxides into block copolymer nanopatterns as robust etch masks for nanolithography

Directed self-assembly (DSA) of block copolymers (BCPs) is a prime candidate to further extend dimensional scaling of silicon integrated circuit features for the nanoelectronic industry. Top-down optical techniques employed for photoresist patterning are predicted to reach an endpoint due to diffraction limits. Additionally, the prohibitive costs for “fabs” and high volume manufacturing tools are issues that have led the search for alternative complementary patterning processes. This thesis reports the fabrication of semiconductor features from nanoscale on-chip etch masks using “high χ” BCP materials. Fabrication of silicon and germanium nanofins via metal-oxide enhanced BCP on-chip etch masks that might be of importance for future Fin-field effect transistor (FinFETs) application are detailed.

Interstitial insertion of varying amounts of ABL-containing genetic material into chromosome 22 in Ph-negative CML.

We studied the cells from three selected patients with Ph-chromosome-negative chronic myeloid leukemia (CML) by Southern blotting, polymerase chain reaction, and in situ hybridization of informative probes to metaphase chromosomes. All three patients had rearrangement of M-BCR sequences in the BCR gene and expression of one or other of the mRNA species characteristic of Ph-positive CML. Leukemic metaphases studied after trypsin-Giemsa banding were indistinguishable from normal. The ABL probe localized both to chromosome 9 and 22 in each case. A probe containing 3' M-BCR sequences localized only to chromosome 22, and not to chromosome 9 as would be expected in Ph-positive CML. Two new probes that recognize different polymorphic regions distal to the ABL gene on chromosome 9 in normal subjects localized exclusively to chromosome 9 in two patients and to both chromosomes 9 and 22 in one patient. These results show that Ph-negative CML with BCR rearrangement is associated with insertion of a variable quantity of chromosome 9 derived material into chromosome 22q11; there is no evidence for reciprocal translocation of material from chromosome 22 to chromosome 9.

Performance analysis of a register insertion ring with a variable size buffer

There has been a recent revival of interest in the register insertion (RI) protocol because of its high throughput and low delay characteristics. Several variants of the protocol have been investigated with a view to integrating voice and data applications on a single local area network (LAN). In this paper the performance of an RI ring with a variable size buffer is studied by modelling and simulation. The chief advantage of the proposed scheme is that an efficient but simple bandwidth allocation scheme is easily incorporated. Approximate formulas are derived for queue lengths, queueing times, and total end-to-end transfer delays. The results are compared with previous analyses and with simulation estimates. The effectiveness of the proposed protocol in ensuring fairness of access under conditions of heavy and unequal loading is investigated.

Performance evaluation of the register insertion protocol for voice-data integration

The performance of the register insertion protocol for mixed voice-data traffic is investigated by simulation. The simulation model incorporates a common insertion buffer for station and ring packets. Bandwidth allocation is achieved by imposing a queue limit at each node. A simple priority scheme is introduced by allowing the queue limit to vary from node to node. This enables voice traffic to be given priority over data. The effect on performance of various operational and design parameters such as ratio of voice to data traffic, queue limit and voice packet size is investigated. Comparisons are made where possible with related work on other protocols proposed for voice-data integration. The main conclusions are: (a) there is a general degradation of performance as the ratio of voice traffic to data traffic increases, (b) substantial improvement in performance can be achieved by restricting the queue length at data nodes and (c) for a given ring utilisation, smaller voice packets result in lower delays for both voice and data traffic.

Genome- and transcriptome-assisted development of nuclear insertion/deletion markers for Calanus species (Copepoda: Calanoida) identification

Copepods of the genus Calanus are key zooplankton species in temperate to arctic marine ecosystems. Despite their ecological importance, species identification remains challenging. Furthermore, the recent report of hybrids among Calanus species highlights the need for diagnostic nuclear markers to efficiently identify parental species and hybrids. Using next-generation sequencing analysis of both the genome and transcriptome from two sibling species, Calanus finmarchicus and Calanus glacialis, we developed a panel of 12 nuclear insertion/deletion markers. All the markers showed species-specific amplicon length. Furthermore, most of the markers were successfully amplified in other Calanus species, allowing the molecular identification of Calanus helgolandicus, Calanus hyperboreus and Calanus marshallae.