Polycentric cultural framework for infrastructure procurement in Nigeria

The high failure rate of most infrastructures in sub-Saharan Africa is alarming, particularly in Nigeria, where the dearth and deterioration of infrastructure constantly imposes severe constraints on economic growth and development. Consequently, existing institutions or strategies which are designed to reproduce effective infrastructures in areas that lack them have been mostly unsuccessful. A carefully conducted survey covering the six geopolitical zones in Nigeria identified inadequate maintenance and inconsistent procurement strategies as the major factors responsible for unsustainable infrastructure delivery. In view of the fact that a stable infrastructure is an essential prerequisite for sustainable development, this paper presents a polycentric cultural framework for infrastructure maintenance and procurement in Nigeria, a framework which emphasises the integration of infrastructure users throughout the process, from conceptualization to actual delivery of infrastructure, by taking the recipients’ culture, beliefs and values into account. It also emphasises the use of systemic referendum amongst users and stakeholders via the traditional consultative processes before the actual delivery of infrastructure and services.N/

Infrastructure delays and cost escalation: Causes and effects in Nigeria

One of the major outcomes of the present ailing social and economic conditions in sub-Saharan Africa is the enormous waste of resources due to project delay and cost escalation in the region. This paper critically analyses the causes and effects of project delay and cost escalation in sub-Saharan Africa taking Nigeria as a case study. The major causes of project delay and cost escalation in Nigeria from the experimental survey were acknowledged and ranked. The ranking was carried out using the relative net difference between the mean severity index percentage and the standard error of mean percentage in order to achieve unambiguously the ranking for each variable factor. Empirical analysis revealed the consequences of project delays and cost escalation for some completed projects in Nigeria with these subsequent findings: the minimum average percentage escalation cost of projects in Nigeria was 14%; the minimum average percentage escalation period of projects in Nigeria was found to be 188% with an average percentage completion work of just 96%. To enhance the ability to study this disturbing trend in the future, some mathematical relationships to forecast future project delays and cost escalation effects in Nigeria was developed. It was recommended that efficient manpower and material systems, alternative financial strategies and increased contingency allowance pattern in pre-contract estimates be developed.N/

CO excitation in four IR luminous galaxies

The correlation between the CO and far infrared luminosities of spiral galaxies is well established. The luminosity ration, L sub FIR/L sub CO in IR luminous active galaxies is, however, systematically five to ten times higher than in ordinary spirals and molecular clouds in our Galaxy. Furthermore, the masses of molecular hydrogen in luminous galaxies are large, M (H2) approx. equals 10(exp 10) solar magnitude, which indicates the observed luminosity ratios are due to an excess of infrared output, rather than a deficiency of molecular gas. These large amounts of molecular gas may fuel luminous galaxies through either star formation or nuclear activity. This interpretation rests on applying the M (H2)/L sub CO ratio calibrated in our Galaxy to galaxies with strikingly different luminosity ratios. But are the physical conditions of the molecular gas different in galaxies with different luminosity ratios. And, if so, does the proportionality between CO and H2 also vary among galaxies. To investigate these questions researchers observed CO (2 to 1) and (1 to 0) emission from four luminous galaxies with the Institute for Radio Astronomy in the Millimeter range (IRAM) 30 m telescope. Researchers conclude that most of the CO emission from these Arp 193, Arp 220, and Mrk 231 arises in regions with moderate ambient densities similar to the clouds in the Milky Way molecular ring. The emission is neither from dense hot cloud cores nor from the cold low density gas characteristic of the envelopes of dark clouds

The contribution of the lateral line to \u27hearing\u27 in fish

In the underwater environment, sound propagates both as a pressure wave and as particle displacement, with particle displacement dominating close to the source (the nearfield). At the receptor level, both the fish ear and the neuromast hair cells act as displacement detectors and both are potentially stimulated by the particle motion component of sound sources, especially in the nearfield. A now common way to test ?hearing\u27 in fish involves auditory evoked potentials (AEPs), with recordings made from electrodes implanted near the auditory brainstem. These AEP recordings are typically conducted in enclosed acoustic environments with the fish well within the nearfield, especially for lower frequencies. We tested the contribution of neuromast hair cells to AEP by first testing intact goldfish (Carassius auratus), then ablating their neuromasts with streptomycin sulphate-disabling superficial and canal neuromasts-and retesting the same goldfish. We performed a similar experiment where only the superficial neuromasts were physically ablated. At 100 and 200Hz, there was a 10-15?dB increase in threshold after streptomycin treatment but no significant difference at higher frequencies. There was no difference in threshold in control fish or in fish that only had superficial neuromasts removed, indicating that the differential responses were driven by canal neuromasts. Taken together, these results indicate that AEP results at lower frequencies should be interpreted as multimodal responses, rather than as \u27hearing\u27. The results also suggest that in natural situations both the ear and lateral line likely play an integrative role in detecting and localising many types of \u27acoustic\u27 stimuli. © 2013. Published by The Company of Biologists Ltd

The private versus public infrastructure in Sub-Saharan Africa: An empirical validation

The macroeconomics of the relationship between the private and public infrastructure in sub-Saharan Africa has been very unpredictable due to the region’s ineffective planning and policy formulation for infrastructure and service delivery. This paper examines the relationship between public and private infrastructure in subSaharan Africa. It also demonstrates that sub-Saharan Africa consumes more and invests less when compared to the industrialised world and that the present domestic investments in sub-Saharan Africa are actually more in the hands of the private sector. Lastly, an inference relationship for measuring and comparing economic stability between countries and regions was formulated, with the industrialised countries as a reference value.N/

Infrastructure delays and cost escalations: causes and effects in Nigeria

One of the major outcomes of the present ailing social and economic conditions in sub-Saharan Africa is the enormous waste of resources due to project delay and cost escalation in the region. This paper critically analyses the causes and effects of project delay and cost escalation in sub-Saharan Africa taking Nigeria as a case study. The major causes of project delay and cost escalation in Nigeria from experimental survey were acknowledged and ranked. The ranking was carried out using the relative net difference between the mean severity index percentage and the standard error of mean percentage in order to achieve unambiguously the ranking for each variable factor. Empirical analysis revealed the consequences of project delays and cost escalation for some completed projects in Nigeria with these subsequent findings: the minimum average percentage escalation cost of projects in Nigeria was 14%; the minimum average percentage escalation period of projects in Nigeria was found to be 188% with an average percentage completion work of just 96%. To enhance the ability to study this disturbing trend in the future, some mathematical relationships to forecast future project delays and cost escalation effects in Nigeria was developed. It was recommended that efficient man power and material systems, alternative financial strategies and increased contingency allowance pattern in pre-contract estimates be developed

Pressure and particle motion detection thresholds in fish: A re-examination of salient auditory cues in teleosts

The auditory evoked potential technique has been used for the past 30years to evaluate the hearing ability of fish. The resulting audiograms are typically presented in terms of sound pressure (dB re. 1Pa) with the particle motion (dB re. 1ms–2) component largely ignored until recently. When audiograms have been presented in terms of particle acceleration, one of two approaches has been used for stimulus characterisation: measuring the pressure gradient between two hydrophones or using accelerometers. With rare exceptions these values are presented from experiments using a speaker as the stimulus, thus making it impossible to truly separate the contribution of direct particle motion and pressure detection in the response. Here, we compared the particle acceleration and pressure auditory thresholds of three species of fish with differing hearing specialisations, goldfish (Carassius auratus, weberian ossicles), bigeye (Pempheris adspersus, ligamentous hearing specialisation) and a third species with no swim bladder, the common triplefin (Forstergyian lappillum), using three different methods of determining particle acceleration. In terms of particle acceleration, all three fish species have similar hearing thresholds, but when expressed as pressure thresholds goldfish are the most sensitive, followed by bigeye, with triplefin the least sensitive. It is suggested here that all fish have a similar ability to detect the particle motion component of the sound field and it is their ability to transduce the pressure component of the sound field to the inner ear via ancillary hearing structures that provides the differences in hearing ability. Therefore, care is needed in stimuli presentation and measurement when determining hearing ability of fish and when interpreting comparative hearing abilities between species

Neuropathologic basis of frontotemporal dementia in progressive supranuclear palsy.

BackgroundProgressive supranuclear palsy (PSP) is a neurodegenerative disorder characterized by neuronal loss in the extrapyramidal system with pathologic accumulation of tau in neurons and glia. The most common clinical presentation of PSP, referred to as Richardson syndrome, is that of atypical parkinsonism with vertical gaze palsy, axial rigidity, and frequent falls. Although cognitive deficits in PSP are often ascribed to subcortical dysfunction, a subset of patients has dementia with behavioral features similar to the behavioral variant of frontotemporal dementia. In this study we aimed to identify the clinical and pathological characteristics of PSP presenting with frontotemporal dementia.MethodsIn this study, we compared clinical and pathologic characteristics of 31 patients with PSP with Richardson syndrome with 15 patients with PSP with frontotemporal dementia. For pathological analysis, we used semiquantitative methods to assess neuronal and glial lesions with tau immunohistochemistry, as well image analysis of tau burden using digital microscopic methods.ResultsWe found greater frontal and temporal neocortical neuronal tau pathology in PSP with frontotemporal dementia compared with PSP with Richardson syndrome. White matter tau pathology was also greater in PSP with frontotemporal dementia than PSP with Richardson syndrome. Genetic and demographic factors were not associated with atypical distribution of tau pathology in PSP with frontotemporal dementia.ConclusionsThe results confirm the subset of cognitive-predominant PSP mimicking frontotemporal dementia in PSP. PSP with frontotemporal dementia has distinct clinical features that differ from PSP with Richardson syndrome, as well as differences in distribution and density of tau pathology. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society

Modelling in ranking procedures: A case study of infrastructure failures in Nigeria

The lack of a scientific approach as to which factors are considered or chosen in a decision-making process can seriously influence the effectiveness of that process. Using the example of infrastructure failures in Nigeria, this paper presents a severity index in matrix order (SIMO) model that unambiguously ranks factors and also defines a threshold that demarcates between major variable factors that should not be compromised in policy and less important ones. Infrastructures failures in Nigeria have hindered economic processes which were meant to alleviate poverty. Constraints responsible for this situation are identified from a carefully conducted survey in Nigeria. Severity of these constraints is empirically ranked using a developed severity index in matrix order (SIMO) model. However, the investigation reveals that corruption, misallocation of investments, inadequate maintenance, lack of transparency and accountability, insufficient funding for infrastructure, lack of supportive institutions, inconsistent political, social and economic policies and the lack of suitable technical and managerial skill are the major variable factors responsible for infrastructure failures in Nigeria.N/

Cerebellar c9RAN proteins associate with clinical and neuropathological characteristics of C9ORF72 repeat expansion carriers.

Clinical and neuropathological characteristics associated with G4C2 repeat expansions in chromosome 9 open reading frame 72 (C9ORF72), the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia, are highly variable. To gain insight on the molecular basis for the heterogeneity among C9ORF72 mutation carriers, we evaluated associations between features of disease and levels of two abundantly expressed "c9RAN proteins" produced by repeat-associated non-ATG (RAN) translation of the expanded repeat. For these studies, we took a departure from traditional immunohistochemical approaches and instead employed immunoassays to quantitatively measure poly(GP) and poly(GA) levels in cerebellum, frontal cortex, motor cortex, and/or hippocampus from 55 C9ORF72 mutation carriers [12 patients with ALS, 24 with frontotemporal lobar degeneration (FTLD) and 19 with FTLD with motor neuron disease (FTLD-MND)]. We additionally investigated associations between levels of poly(GP) or poly(GA) and cognitive impairment in 15 C9ORF72 ALS patients for whom neuropsychological data were available. Among the neuroanatomical regions investigated, poly(GP) levels were highest in the cerebellum. In this same region, associations between poly(GP) and both neuropathological and clinical features were detected. Specifically, cerebellar poly(GP) levels were significantly lower in patients with ALS compared to patients with FTLD or FTLD-MND. Furthermore, cerebellar poly(GP) associated with cognitive score in our cohort of 15 patients. In the cerebellum, poly(GA) levels similarly trended lower in the ALS subgroup compared to FTLD or FTLD-MND subgroups, but no association between cerebellar poly(GA) and cognitive score was detected. Both cerebellar poly(GP) and poly(GA) associated with C9ORF72 variant 3 mRNA expression, but not variant 1 expression, repeat size, disease onset, or survival after onset. Overall, these data indicate that cerebellar abnormalities, as evidenced by poly(GP) accumulation, associate with neuropathological and clinical phenotypes, in particular cognitive impairment, of C9ORF72 mutation carriers