Efficient fault diagnosis of helicopter gearboxes

Application of a diagnostic system to a helicopter gearbox is presented. The diagnostic system is a nonparametric pattern classifier that uses a multi-valued influence matrix (MVIM) as its diagnostic model and benefits from a fast learning algorithm that enables it to estimate its diagnostic model from a small number of measurement-fault data. To test this diagnostic system, vibration measurements were collected from a helicopter gearbox test stand during accelerated fatigue tests and at various fault instances. The diagnostic results indicate that the MVIM system can accurately detect and diagnose various gearbox faults so long as they are included in training

Women Fighting Poverty in Cameroon: A Legal Perspective!

Poverty in Sub Saharan Africa has many causes, which range from the impact of the Structural Adjustment Programs, the huge foreign debt and policies that encourage mismanagement of state resources. This growing poverty and underdevelopment has attracted the attention of the international community to pursue programs aimed at attaining the UN Millennium Development Goals, foreign debt relief and increased development aid. During the introduction of policies that brought about economic hardship, African women were not consulted and their voices were not heard. Yet it is these women who feel most of the impact of these policies. During the period of the economic crisis, women did not remain silent in the face of the growing poverty. As a response, they organized themselves into groups for financial and self-help purposes. These organized women’s groups if legally and financially empowered will contribute a great deal in the fight against poverty in Cameroon. Micro financing is an important tool common in these groups, but it must be supported by the provision of basic resources and infrastructure. Women make up more than75% of subsistence farmers and are mostly found in the informal sector, their contribution helps to sustain the economy greatly, but it is still insufficient to make any significant improvement in their living standards. The inhibition stems from traditional and cultures practices that hinder women from claiming equal ownership and equal representation in decision-making settings. Hence, a good economic regulatory framework by any government fighting poverty should incorporate the economic and legal empowerment of women and target mostly rural women and their basic needs

Prosthetic glenoid fixation: lateralisation of the centre of rotation of a fixed-fulcrum total shoulder replacement is not associated with suboptimal glenoid bone formation during a functionally-relevant loading protocol

Prosthetic glenoid fixation: lateralisation of the centre of rotation of a fixed-fulcrum total shoulder replacement is not associated with suboptimal glenoid bone formation during a functionally-relevant loading protocol

A new broken U(1)-symmetry in extreme type-II superconductors

A phase transition within the molten phase of the Abrikosov vortex system without disorder in extreme type-II superconductors is found via large-scale Monte-Carlo simulations. It involves breaking a U(1)-symmetry, and has a zero-field counterpart, unlike vortex lattice melting. Its hallmark is the loss of number-conservation of connected vortex paths threading the entire system {\it in any direction}, driving the vortex line tension to zero. This tension plays the role of a generalized ``stiffness'' of the vortex liquid, and serves as a probe of the loss of order at the transition, where a weak specific heat anomaly is found.Comment: 5 pages, 3 figure

Isolation and characterization of cDNA clones for α- and β-subunits of ovine luteinizing hormone

A cDNA library of ovine pituitary DNA in plasmid pBR322 has been constructed by conventional methods with certain modifications. The library was screened using partial cDNAs for rat α-subunit and LHβ. We have isolated cDNA clones for ovineα -subunit and LHβ. The identification of these clones was confirmed by partial sequencing. The clones bear about 80% sequence homology with the respective rat cDNAs in the sequenced regions and hybridize with the rat clones in 5 X SSC at 55°C. The ovine LHβ clone has an insert of about 650 bp and selects an RNA of about 750 bases in a northern blot. The α-subunit cDNA clone has an insert of about 550 bp; it has two internal Pst I sites and thus shows restriction-based differences from rat α-subunit cDNA, which does not have anyPst I site

Quantum dynamics in photonic crystals

Employing a recently developed method that is numerically accurate within a model space simulating the real-time dynamics of few-body systems interacting with macroscopic environmental quantum fields, we analyze the full dynamics of an atomic system coupled to a continuum light-field with a gapped spectral density. This is a situation encountered, for example, in the radiation field in a photonic crystal, whose analysis has been so far been confined to limiting cases due to the lack of suitable numerical techniques. We show that both atomic population and coherence dynamics can drastically deviate from the results predicted when using the rotating wave approximation, particularly in the strong coupling regime. Experimental conditions required to observe these corrections are also discussed.Comment: 5 pages, 2 figures Updated with published versio

Saccharomyces cerevisiae kinetochore protein (rDsn1p) induced apoptosis in Chinese hamster ovary cells

Dsn1p is a member of the MIND complex that forms part of the yeast kinetochore, which is essential for the proper chromosomal segregation during cell division. Its functionality is gene dosage dependent and it has characteristics of haploinsufficiency. Bioinformatics alignments predicted the existence of nuclear homologues in higher eukaryotic organisms. Literature on the possibility of Dsn1p being a functional homologue of these organisms is scarce. In this study we employed recombinant DNA expression technology to explore whether Dsn1p can function in a mammalian cell line, Chinese Hamster Ovary (CHO). Expression of rDsn1p in CHO cells induced cytopathic effects including changes in cellular morphology and cell size. Inhibition of cell growth was observed at the beginning the fourth post-transfection week. The recombinant CHO cell culture showed cytotoxic effects following the accumulation of the Dsn1p, resulting in apoptotic cell death; as evidenced by the presence of nuclear fragmentation and surface blebbing in the dying cells. This suggests that rDsn1p may interact with the counterpart/ligand of the nuclear homologue of this protein in CHO cells, resulting in nuclear anomalies and inhibition of cell growth, as observed in our previous study using yeast cells

Pure Gas of Optically Trapped Molecules Created from Fermionic Atoms

We report on the production of a pure sample of up to 3x10^5 optically trapped molecules from a Fermi gas of 6Li atoms. The dimers are formed by three-body recombination near a Feshbach resonance. For purification a Stern-Gerlach selection technique is used that efficiently removes all trapped atoms from the atom-molecule mixture. The behavior of the purified molecular sample shows a striking dependence on the applied magnetic field. For very weakly bound molecules near the Feshbach resonance, the gas exhibits a remarkable stability with respect to collisional decay.Comment: 4 pages, 5 figure