Appraisal of Ferry Terminals Design Compliance to Guidelines for Universal Accessibility in Lagos State Nigeria

Accessibility of public buildings has been an issue of global interest and importance in the society in recent times. It has been promoted by the need to ensure universal equality and end discrimination of persons either based on size, ability and mobility disorder. Given the important role of water transportation in aiding mobility, movement of goods and services in coastal cities such as Lagos, this study reviewed the compliance of design, construction and operation of Ferry Terminals towards accessibility of users. The research adopts the case study approach and interviews in appraising the three existing Ferry Terminals in Lagos State, Nigeria for accessibility compliance. The case study involved observation and evaluation of the facilities, and the interviews focused on 18 of the ‘facilities operators and passengers’ about their experiences of associated facilities. Findings from the study revealed poor compliance to accessibility in both the external and internal environments. As such, there is a high degree of limitation in use of the facilities for all facets of water travel; from building approach; waiting, boarding and disembarking areas. Existing facilities have inadequate accessibility and are below standards to ensure use by all and without discrimination or segregation of users. It is therefore imperative for Ferry terminal buildings and amenities to be accessible in effectively enabling all users achieve true mobility in barrier-free environments that foster user-comfort through the adoption and application of universal design principle

Palynology and micropalaeontology of the Pliocene - Pleistocene transition in outcrop from the western Caspian Sea, Azerbaijan : potential links with the Mediterranean, Black Sea and the Arctic Ocean?

New palynological, ostracod and foraminiferal data are presented from a long outcrop section in the Jeirankechmez river valley, Azerbaijan, near the western coast of the Caspian Sea. The interval studied includes the upper part of the Psliocene Productive Series and overlying Plio-Pleistocene Akchagylian (Akchagyl) and Apsheronian (Apsheron) regional stages. Productive Series sediments were deposited in a closed fluvio-lacustrine basin, isolated from any marine influence. The onset of Akchagyl deposition is marked by a lithological change associated with a significant flooding event that, at its maximum extent, reached the Sea of Azov and into present-day Iran, Kazakhstan, Turkmenistan and Russia. At the Jeirankechmez locality, the lowermost beds of the Akchagyl contain predominantly freshwater assemblages with very minimal marine or brackish content showing that the onset of Akchagyl deposition was not a marine induced event. Reworked Mesozoic palynomorphs occur frequently in this lowermost interval, including the reworked pollen taxa Aquilapollenites-Triprojectus that were eroded from the north or north-east. Significant marine influence is evident ca. 30 m above the base of the Akchagyl in the studied outcrop, marked by the ‘Cassidulina Beds’ which contain a distinct but low diversity assemblage of foraminifera that occurs widely and can be correlated in many parts of the greater Caspian region. Dinoflagellate cysts (dinocysts) in the marine interval include frequent specimens very similar to Algidasphaeridium capillatum (Matsuoka and Bujak), a species only previously recorded from the northern Bering Sea. The combined evidence from these dinocysts and foraminifera suggests that a marine (i.e. seaway) connection existed briefly between the Arctic Ocean and the Caspian Sea at the very end of the Pliocene. Re-examination of core material from the Adriatic Sea shows that Cassidulina reniforme (Nørvang) was present in the Mediterranean during and shortly after the Last Glacial Maximum. The possibility that the end Pliocene marine incursion came from the Mediterranean via the Black Sea region to the Caspian Sea cannot be entirely ruled out but is considered unlikely. Biometric analyses are applied to obtain a better understanding of the palaeoenvironmental significance of the assemblages dominated by cassidulinids. An interval > 300 m thick is assigned to the Apsheron regional stage on the basis of predominantly brackish ostracod and dinocyst associations. The dinocysts are of ‘Peri-Paratethyan’ affinity and closely resemble species first described from Miocene and Pliocene sediments in the Pannonian and Dacic basins of Eastern Europe. Many similarities exist in the microplankton records (dinocysts and acritarchs) between the Caspian Sea, the Black Sea and Central Paratethys.PostprintPeer reviewe

The Seventh Data Release of the Sloan Digital Sky Survey

This paper describes the Seventh Data Release of the Sloan Digital Sky Survey (SDSS), marking the completion of the original goals of the SDSS and the end of the phase known as SDSS-II. It includes 11663 deg^2 of imaging data, with most of the roughly 2000 deg^2 increment over the previous data release lying in regions of low Galactic latitude. The catalog contains five-band photometry for 357 million distinct objects. The survey also includes repeat photometry over 250 deg^2 along the Celestial Equator in the Southern Galactic Cap. A coaddition of these data goes roughly two magnitudes fainter than the main survey. The spectroscopy is now complete over a contiguous area of 7500 deg^2 in the Northern Galactic Cap, closing the gap that was present in previous data releases. There are over 1.6 million spectra in total, including 930,000 galaxies, 120,000 quasars, and 460,000 stars. The data release includes improved stellar photometry at low Galactic latitude. The astrometry has all been recalibrated with the second version of the USNO CCD Astrograph Catalog (UCAC-2), reducing the rms statistical errors at the bright end to 45 milli-arcseconds per coordinate. A systematic error in bright galaxy photometr is less severe than previously reported for the majority of galaxies. Finally, we describe a series of improvements to the spectroscopic reductions, including better flat-fielding and improved wavelength calibration at the blue end, better processing of objects with extremely strong narrow emission lines, and an improved determination of stellar metallicities. (Abridged)Comment: 20 pages, 10 embedded figures. Accepted to ApJS after minor correction

Intrinsically determined cell death of developing cortical interneurons

Cortical inhibitory circuits are formed by GABAergic interneurons, a cell population that originates far from the cerebral cortex in the embryonic ventral forebrain. Given their distant developmental origins, it is intriguing how the number of cortical interneurons is ultimately determined. One possibility, suggested by the neurotrophic hypothesis1-5, is that cortical interneurons are overproduced, and then following their migration into cortex, excess interneurons are eliminated through a competition for extrinsically derived trophic signals. Here we have characterized the developmental cell death of mouse cortical interneurons in vivo, in vitro, and following transplantation. We found that 40% of developing cortical interneurons were eliminated through Bax- (Bcl-2 associated X-) dependent apoptosis during postnatal life. When cultured in vitro or transplanted into the cortex, interneuron precursors died at a cellular age similar to that at which endogenous interneurons died during normal development. Remarkably, over transplant sizes that varied 200-fold, a constant fraction of the transplanted population underwent cell death. The death of transplanted neurons was not affected by the cell-autonomous disruption of TrkB (tropomyosin kinase receptor B), the main neurotrophin receptor expressed by central nervous system (CNS) neurons6-8. Transplantation expanded the cortical interneuron population by up to 35%, but the frequency of inhibitory synaptic events did not scale with the number of transplanted interneurons. Together, our findings indicate that interneuron cell death is intrinsically determined, either cell-autonomously, or through a population-autonomous competition for survival signals derived from other interneurons

Retinoic Acid Functions as a Key GABAergic Differentiation Signal in the Basal Ganglia

Retinoic acid (RA) is essential for the generation of GABAergic inhibitory neurons in the mouse forebrain, and RA treatment of embryonic stem cells induces the production of GABAergic neurons

The Level of the Transcription Factor Pax6 Is Essential for Controlling the Balance between Neural Stem Cell Self-Renewal and Neurogenesis

Neural stem cell self-renewal, neurogenesis, and cell fate determination are processes that control the generation of specific classes of neurons at the correct place and time. The transcription factor Pax6 is essential for neural stem cell proliferation, multipotency, and neurogenesis in many regions of the central nervous system, including the cerebral cortex. We used Pax6 as an entry point to define the cellular networks controlling neural stem cell self-renewal and neurogenesis in stem cells of the developing mouse cerebral cortex. We identified the genomic binding locations of Pax6 in neocortical stem cells during normal development and ascertained the functional significance of genes that we found to be regulated by Pax6, finding that Pax6 positively and directly regulates cohorts of genes that promote neural stem cell self-renewal, basal progenitor cell genesis, and neurogenesis. Notably, we defined a core network regulating neocortical stem cell decision-making in which Pax6 interacts with three other regulators of neurogenesis, Neurog2, Ascl1, and Hes1. Analyses of the biological function of Pax6 in neural stem cells through phenotypic analyses of Pax6 gain- and loss-of-function mutant cortices demonstrated that the Pax6-regulated networks operating in neural stem cells are highly dosage sensitive. Increasing Pax6 levels drives the system towards neurogenesis and basal progenitor cell genesis by increasing expression of a cohort of basal progenitor cell determinants, including the key transcription factor Eomes/Tbr2, and thus towards neurogenesis at the expense of self-renewal. Removing Pax6 reduces cortical stem cell self-renewal by decreasing expression of key cell cycle regulators, resulting in excess early neurogenesis. We find that the relative levels of Pax6, Hes1, and Neurog2 are key determinants of a dynamic network that controls whether neural stem cells self-renew, generate cortical neurons, or generate basal progenitor cells, a mechanism that has marked parallels with the transcriptional control of embryonic stem cell self-renewal

Origins of Cortical GABAergic Neurons in the Cynomolgus Monkey

In human most cortical γ-aminobutyric acidergic (GABAergic) neurons are produced in the proliferative zones of the dorsal telencephalon in contrast to rodents. We report that in cynomolgus monkey fetuses cortical GABAergic neurons are generated in the proliferative zones of the dorsal telencephalon, in addition to the proliferative region of the ventral telencephalon, the ganglionic eminence (GE), however, with a temporal delay. GABAergic neuron progenitors labeled for Mash1 and GAD65 were present mainly in the GE at embryonic days (E) 47–55, and in the entire dorsal telencephalon at E64–75. These progenitors within the dorsal telencephalon are generated locally rather than in the GE. The ventral and dorsal lineages of cortical GABAergic neurons display different laminar distribution. Early generated GABAergic neurons from the GE mostly populate the marginal zone and subplate, whereas cortical plate GABAergic neurons originate from both ventral and dorsal telencephalon. A differential regulation of the two GABA synthesizing enzymes (GAD65 and GAD67) parallels GABAergic neuron differentiation. GAD65 is preferentially expressed in GABAergic progenitors and migrating neurons, GAD67 in morphologically differentiated neurons. Therefore, the dorsal telencephalic origin of cortical GABAergic neurons is not human-specific but appears as a former event in the ascent of evolution that could provide GABAergic neurons to an expending neocortex

Optimization of interneuron function by direct coupling of cell migration and axonal targeting

Neural circuit assembly relies on the precise synchronization of developmental processes, such as cell migration and axon targeting, but the cell-autonomous mechanisms coordinating these events remain largely unknown. Here we found that different classes of interneurons use distinct routes of migration to reach the embryonic cerebral cortex. Somatostatin-expressing interneurons that migrate through the marginal zone develop into Martinotti cells, one of the most distinctive classes of cortical interneurons. For these cells, migration through the marginal zone is linked to the development of their characteristic layer 1 axonal arborization. Altering the normal migratory route of Martinotti cells by conditional deletion of Mafb—a gene that is preferentially expressed by these cells—cell-autonomously disrupts axonal development and impairs the function of these cells in vivo. Our results suggest that migration and axon targeting programs are coupled to optimize the assembly of inhibitory circuits in the cerebral cortex

Novel animal models for studying complex brain disorders: BAC-driven miRNA-mediated in vivo silencing of gene expression

In schizophrenia, glutamic acid decarboxylase 1 (GAD1) disturbances are robust, consistently observed, cell-type specific and represent a core feature of the disease. In addition, neuropeptide Y (NPY), which is a phenotypic marker of a sub-population of GAD1-containing interneurons, has shown reduced expression in the prefrontal cortex in subjects with schizophrenia, suggesting that dysfunction of the NPY+ cortical interneuronal sub-population might be a core feature of this devastating disorder. However, modeling gene expression disturbances in schizophrenia in a cell type-specific manner has been extremely challenging. To more closely mimic these molecular and cellular human post-mortem findings, we generated a transgenic mouse in which we downregulated GAD1 mRNA expression specifically in NPY+ neurons. This novel, cell type-specific in vivo system for reducing gene expression uses a bacterial artificial chromosome (BAC) containing the NPY promoter-enhancer elements, the reporter molecule (eGFP) and a modified intron containing a synthetic microRNA (miRNA) targeted to GAD1. The animals of isogenic strains are generated rapidly, providing a new tool for better understanding the molecular disturbances in the GABAergic system observed in complex neuropsychiatric disorders such as schizophrenia. In the future, because of the small size of the silencing miRNAs combined with our BAC strategy, this method may be modified to allow generation of mice with simultaneous silencing of multiple genes in the same cells with a single construct, and production of splice-variant-specific knockdown animals