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MTR Asset Management System has been one of the initiatives bringing strategic transformations. The MTR Asset Management System itself has been accredited to PAS55 since 2005. The ALA Scheme specifically aims at confirming the capability of individual assets in the MTR Operating Railway in meeting the operating demands of the required performance and safety standards for the rest of the assets' assured life. More importantly from an asset management perspective, it derives an ALA plan, which specifies the various life assurance strategies and measures for life extension or renewal. In addition, it stipulates the estimates of funding required over the project horizon. The ALA Scheme in MTR was launched in 2008. It proposes a more flexible approach to asset management other than rigidly linking the planned replacement of assets with their specified design life. The Scheme specifies a target life for individual assets, which is driven by an asset's capability to meet performance standards, through identifying the “life limiting factors”, and implementation of life assurance measures. The first programme took about 2 years to complete. Upon completion of the programme, the ALA Scheme was further fine tuned into a formal, structured and permanent asset management policy. The ALA Scheme for the MTR Operating Railway has been proved successful in achieving the objectives in maximising the useful life of an asset and optimising total life cycle costs whilst meeting the stringent technical and customer service performance requirements; essentially bringing real benefits to different stakeholders, be they the passengers, employees, investors, and regulators. ("EMU") running in the MTR Kwun Tong, Tsuen Wan, Island and Tseung Kwan O lines which serve the main urban areas of Hong Kong ("MTR Lines"), will be used as an example to illustrate the study approach on how its life is further extended from 40 to 50 years, and the major tasks and strategies deployed. (5 pages)

Schizophrenia is a severe mental disorder with onset frequently in adolescence and followed by a chronic and disabling course. Although the exact pathophysiology of this devastating disorder has not been clearly elucidated, a large part of it has been attributed to genetic influences. This article seeks to provide an overview on what our group has embarked on--to elucidate genetic risk factors for schizophrenia within the Chinese ethnic group.We plan to conduct an integrated approach to interrogate comprehensively the genome from different angles and in stages. The first stage involves a genome-wide association study of 1000 cases of schizophrenia-control pairs, with a follow-up replication study in another 1000 cases of schizophrenia and in 1000 controls, and combination analyses with groups from other places including China and Hong Kong. Other than the genome-wide association study, gene sequencing for purported candidate genes and copy number variation analysis will be performed. Neurocognitive intermediate phenotypes will be employed to deconstruct the complex schizophrenia phenotype in a bid to improve association findings. Promising leads from longitudinal gene and protein expression in ultra-high-risk subjects who develop psychosis and schizophrenia (in a parallel study) will be followed up as candidate genes and sequenced in the genetic analysis. Functional analysis forms the last stage of this integrated approach.This integrated genetic and genomic approach will hopefully help in further characterizing and deepening our understanding of molecular pathophysiological mechanisms underlying schizophrenia.

Abnormalities of brain white matter have been noted in structural magnetic resonance imaging and diffusion tensor imaging (DTI) studies of bipolar disorder, but there are fewer investigations specifically examining white matter integrity early in the course of illness. In this study, we employed DTI to elucidate white matter changes in adult patients with remitted first-episode mania and hypothesized that first-episode mania was associated with decreased fractional anisotropy in cortical (frontal) and subcortical (thalamus, striatum) white matter as well as white matter tracts (cingulum, corpus callosum).Diffusion tensor images were acquired from 16 patients with remitted first-episode mania and 16 healthy controls matched for age, gender, handedness, and years of education. Fractional anisotropy and radial and axial diffusivities were analyzed using Tract-Based Spatial Statistics.Patients had lower fractional anisotropy and higher radial diffusivity in the left anterior frontal white matter, right posterior thalamic radiation, left cingulum, and bilateral sagittal striatum. In addition, increased radial diffusivity was found in the left corpus callosum.Our findings highlighted that white matter abnormalities were present by the time of remission of first-episode mania. The widespread occurrence of these white matter abnormalities both in first-episode mania and chronic bipolar disorder suggested that disruption of white matter cortical-subcortical networks as well as projection, associative, and commissural tracts is a hallmark of the illness.

This preliminary study was performed to test the reliability and validity of the Brief Assessment of Cognition in Schizophrenia (BACS) as an assessment tool in a Japanese-language version (BACS-J). The subjects for the present study were 30 outpatients with chronic schizophrenia. Each subject gave written informed consent to participate in the research. Cronbach's alpha for the BACS-J was 0.77. The BACS-J composite score was significantly correlated with all primary measures of BACS-J (verbal memory, working memory, motor speed, verbal fluency, attention, and executive function). All BACS-J primary measures and the composite score were significantly correlated between two assessments. The mean score of the Digit Sequencing Task and composite score on the second assessment were significantly larger than those on the first assessment. All BACS-J primary measures except the Symbol Coding Task were significantly correlated with relevant standard neurocognitive tests. Also, the BACS-J composite score was significantly correlated with all standard neurocognitive tests except the Continuous Performance Test. A principal components analysis with varimax rotation resulted in a three-factor solution (executive function and memory; motor speed and general cognitive functions; and working memory). This preliminary study indicates that the BACS-J is a reliable and practical scale to evaluate cognitive function.

The fine structural features of a retinal: melanophage, observed in degenerating retinae of Notophthalmus viridescens is described. The melanophage, believed to originate from the vascular supply, serves for the stepwise degradation of extruded single melanin granules from cellular elements of the pigment epithelium which are forming the regenerated retina.

The process of retinal regeneration in adult Triturus cristatus carnifex was analyzed autoradiographically following tritiated thymidine administration at closely spaced postoperative intervals. In unoperated control animals given five daily doses of labeled thymidine, a continuous input of two types of cells was observed from the ora serrata into the ganglion cell and inner nuclear layers. One cell type appeared to represent retinal neurons with dispersed nuclear chromatin while the second cell type, containing a nucleus with dense heterochromatic rim, was displaced into all retinal layers with time, ultimately appearing within the layer of photoreceptor outer segments approximating the pigment epithelium. In operated animals, both control and operated (enucleated) eyes showed a loss of proliferative capacity from the ora serrata by two days postoperative. Retinal degeneration and regeneration in this species differed from that observed earlier for Notophthalmus viridescens in that: (1) invading pigment epithelia dissected the degenerating retina sequestering the outer nuclear layer between two epithelial sheets for phagocytosis by day 8; (2) degenerating inner retinal cells demonstrated labeling with thymidine and mitotic division before degeneration; (3) the process of removal of retinal and lens debris was assisted by vascularly derived phagocytes. The restoration of the retina involves both cellular addition from the anterior pars ciliaris retina and ora serrata, forming the anterior half of the new retina, and the posterior pigment epithelium, forming the posterior half of the retina from the innermost lamina. Sites of regional cellular proliferation at the vortex veins do not develop in this species. The basal pigment epithelium, upon Bruch's membrane, does not contribute to the retinal regenerate. The species differences presented in the process of retinal regeneration and the implications for the understanding of the generation of retinotectal specificity are discussed. It is concluded that the specificity engendered during both development and regeneration in this system must: (1) be derived from the ganglion cells; (2) be responsible for not only tectal connections but intra-retinal position and connectivity; and, (3) not be temporally related.

The process of retinal degeneration and regeneration in retinectomized or enucleated and reimplanted eyes of adult Notophthalmus viridescens has been studied following staged administrations of tritiated thymidine or colchicine. In control left eyes, no labeled cells were observed in either the retina, pigment epithelium, or ora serrata. In retinectomized or enucleated eyes, retinal degeneration proceeded from the posterior central pole circumferentially to the ora serrata, with complete retinal degeneration being consistently observed. Retinal replacement originated from two cellular sources: the posterior pigment epithelium and the anterior complex, consisting of cells in the ora serrata and pars ciliaris retina. The posterior pigment epithelium gave rise to an initial central retinal portion which differentiated in an annular pattern which extended from the optic nerve to the vortex veins. Cellular addition from the pigment epithelium became restricted to these two regions by day 25. The anterior retinal mass was regenerated from the anterior elements (ora serrata/pars ciliaris retina) with a minor contribution from the underlying anterior pigment epithelium. Data concerning the relative numbers of cellular types involved in the regenerative sequence and the times of their function are presented. Peak labeling occurred in the posterior pigment epithelium at day 20, the pars ciliaris retina at days 18 and 40, and the new retina at days 28 and 41. By 30 days regional sites of cellular proliferation became established that coincided with the pattern of ocular blood vessels. Retinal differentiation followed the pattern commonly observed during retinal development. The significance of these observations with respect to earlier work demonstrating a different sequence for retinal restoration is discussed.

The current status of gravitational biology is summarized, future areas of required basic research in earth-based and spaceflight projects are presented, and potential applications of gravitational biology on a space station are demonstrated. Topics covered include vertebrate reproduction, prenatal/postnatal development, a review of plant space experiments, the facilities needed for growing plants, gravimorphogenesis, thigmomorphogenesis, centrifuges, maintaining a vivarium, tissue culture, and artificial human organ generation. It is proposed that space stations carrying out these types of long-term research be called the National Space Research Facility.

Since the foveal photoreceptors in the duplex retina of adult human and other diurnal primates are closely associated with high visual acuity and spectral sensitivity, observations were made on the pre- and postnatal morphologic development of the macula and fovea in the retina of the diurnal rhesus monkey. Histologic findings on the level of development of the retina at birth revealed a macula with the characteristic foveal depression. Observations on the ultrastructural development of the foveal photoreceptors revealed that their outer and inner segments were relatively well differentiated even at birth. An examination of the prenatal morphogenesis of the photoreceptors in the eye of the fetus indicated that the initial differentiation of the receptors may take place as early as 100 to 125 days after conception. However, the receptors in the specialized fovea continued to develop for 1 to 2 months after birth, whereas the photoreceptors outside the central region of the retina had completed their fine structural development at birth. By the end of the second month after birth, the macular and foveal areas essential for high visual acuity and spectral sensitivity appeared structurally well completed. In general, major maturational changes observable after birth were apparent predominantly in the pigment epithelium of the retina.

The normal adult retina of the North American Urodele, Triturus viridescens, has been studied with the electron microscope. Three basic types of photoreceptors are observed: rods, possibly distinguishable as either red or green rods, single cones, and double cones. The photoreceptors differ from those reported in other amphibia in that: (1) none of photoreceptors contain an oil droplet; (2) all photoreceptors possess an enlarged paraboloid, and, (3) the double cones consist of two complete photoreceptors, a principal cone member and an accessory cone member. The two members are closely related to one another along the length of the inner segment through a clasping of the principal member within cytoplasmic expansions of the accessory member. The principal member inner segment bears strong resemblance to the single cone while the accessory member inner segment is rod-like in nature. The sustentacular elements of this avascular retina display a diversity of scleral processes. The presence of specific collar-like glial ensheathments of the photoreceptors at the external limiting membrane contrasts with the extensive interreceptor contacts between all photoreceptor elements throughout the outer nuclear layer. The synaptic bases are characterized by the presence of three types of specific contact sites: (1) interreceptor contacts among all receptor bases; (2) clusters of fine horizontal cell dendrites penetrate the receptor base and terminate in a superficial spray of typical axodendritic synapses; (3) prominent bipolar dendrites enter within the horizontal cell processes terminating in the typical retinal ribbon synapse. The significance of these observations are discussed with respect to the origin of the amphibian double cone, the metabolic support of the retinal, and the potential integration among the receptor cells.