Urban planning law in Liberia: the case for a transformational approach

This article discusses the need for a fundamental rethinking of urban planning in Liberia with special reference to Monrovia, the capital. Liberia is a post-conflict country and is facing a multitude of problems. One is the very rapid urbanisation of the country. Well over 50% of the population live in urban areas, and over one million people—one third of the population—live in Monrovia, for the most part in informal ‘illegal’ settlements with few facilities. Despite land issues being acknowledged as in need of being tackled as a matter of urgency, little has been done by the Johnson-Sirleaf government since it came to power in 2006. What is needed and what this article argues for is a plan for the development of Monrovia based on the Right to the City with residents given clear rights to land and to participate in the governance of their city. The approach is denominated as a transformational one, taking its inspiration from van der Walt’s approach set out in his Property in the Margins. The need for and the outline of an Urban Transformation Act are set out in the article which concludes with a warning that it cannot be supposed that the residents of Monrovia will continue indefinitely to put up with their very poor living conditions

Periodic methanol masers: from a colliding wind binary (CWB) perspective

Since the discovery of periodic class II methanol masers at 6.7 and 12.2 GHz associated with high-mass star formation regions (HMSFRs), a number of possible driving mechanisms have been proposed to explain this phenomenon. Here, we apply a more realistic treatment of the original colliding wind binary (CWB) model explanation to investigate to what extent it can describe the flare profiles of the periodic methanol masers. It was found that the CWB hypothesis is feasible from an energetics standpoint, because the emission from the shocked gas does cause an outward shift of the position of the ionization front (IF). This confirms that the energy budget available from the shocked gas is enough to be the driving force behind the CWB model. The CWB model describes the light curve of the 1.25 km s−1 12.2 GHz velocity feature of G9.62 + 0.20E very well over 4000 d. The quiescent state flux density of the 1.25 km s−1 velocity feature can also be described very well by the time-dependent change in electron density (ne). The CWB model also describes the other periodic methanol masers, G22.357 + 0.066, G37.55 + 0.20, and G45.473 + 0.134, which have similar light curves, very well. This strongly suggests that these periodic methanol masers can be described by the time-dependent change in the free–free emission from some part of the background H II region against which the masers are projected

An Association Analysis between Mitochondrial DNA A10398G Polymorphism and Temperament in Japanese Young Adults

The mitochondrial (mt) DNA C5178A and A10398G polymorphisms have been reported to be associated with mental disorders such as bipolar disorder. However, the effects of these polymorphisms on temperament in healthy people are poorly understood. Evaluating healthy subjects can have the advantage of providing new strategies for maintaining psychological health and preventing mental illness. We examined the association between mtDNA polymorphisms and temperament in Japanese students. There was no significant difference in examined temperament when analysed by genotypes, 5178–10398 haplotypes, or sex. The subgroup analysis based on sex indicated that there was an interactive effect of the mtDNA A10398G polymorphism and sex on anxiety and obsession. This finding is preliminary and cannot exclude the possibility of false-positive due to small sample size (144 subjects) and multiple statistical testing. Further studies involving a larger sample size or other ethnic groups are necessary to confirm that mtDNA A10398G polymorphism can be a genetic factor for temperament

N-acetyltransferase 2 (NAT2) gene polymorphisms in Parkinson's disease

BACKGROUND: Parkinson's disease (PD) is a movement disorder caused by the degeneration of dopaminergic neurons in the substantia nigra of the midbrain. The molecular basis of this neural death is unknown, but genetic predisposition and environmental factors may cause the disease. Sequence variations in N-acetyltransferase 2 (NAT2) gene leading to slow acetylation process have been associated with PD, but results are contradictory. METHODS: We analyzed three NAT2 genetic variations, c.481C>T, c.590G>A (p.R197Q) and c.857G>A (p.G286E), which are known to result in a slow acetylator phenotype. Using validated PCR-RFLP assays, we genotyped 243 healthy unrelated Caucasian control subjects and 124 PD patients for these genetic variations. Further, we have undertaken a systematic review of NAT2 studies on PD and we incorporated our results in a meta-analysis consisting of 10 studies, 1,206 PD patients and 1,619 control subjects. RESULTS: Overall, we did not find significant differences in polymorphic acetylation genotypes in PD and control subjects. In the meta-analysis of slow acetylators from 10 studies and representing 604/1206 PD vs. 732/1619 control subjects, a marginally significant odds ratio (OR) of 1.32 (95% CI 1.12–1.54, p < 0.05) was obtained. Re-analysis of the data to exclude the only two studies showing positive association of slow acetylators to PD, resulted in a non-significant OR (1.07, 95% CI 0.9–1.28). Furthermore, meta-analysis of studies for c.590G>A, where both allele and genotype frequencies in PD vs. control subjects were analyzed, did not give significant summary odds ratios as well. CONCLUSION: We found little evidence for differences in polymorphic acetylation genotypes in PD and control subjects. Results of the meta-analyses did not also provide conclusive evidence for an overall association of NAT2 slow acetylator genotypes to PD

Ashkenazi Jewish Centenarians Do Not Demonstrate Enrichment in Mitochondrial Haplogroup J

BACKGROUND: Association of mitochondrial haplogroup J with longevity has been reported in several population subgroups. While studies from northern Italy and Finland, have described a higher frequency of haplogroup J among centenarians in comparison to non-centenarian, several other studies could not replicate these results and suggested various explanations for the discrepancy. METHODOLOGY/PRINCIPAL FINDINGS: We have evaluated haplogroup frequencies among Ashkenazi Jewish centenarians using two different sets of matched controls. No difference was observed in the haplogroup J frequencies between the centenarians or either matched control group, despite adequate statistical power to detect such a difference. Furthermore, the lack of association was robust to population substructure in the Ashkenazi Jewish population. Given this discrepancy with the previous reported associations in the northern Italian and the Finnish populations, we conducted re-analysis of these previously published data, which supported one of several possible explanations: i) inadequate matching of cases and controls; ii) inadequate adjustment for multiple comparison testing; iii) cryptic population stratification. CONCLUSIONS/SIGNIFICANCE: There does not exist a universal association of mitochondrial haplogroup J with longevity across all population groups. Reported associations in specialized populations may reflect genetic or other interactions specific to those populations or else cryptic confounding influences, such as inadequate matching attributable to population substructure, which are of general relevance to all studies of the possible association of mitochondrial DNA haplogroups with common complex phenotypes

Lack of evidence for a genetic association between FGF20 and Parkinson's disease in Finnish and Greek patients

BACKGROUND: Fibroblast growth factor 20 (FGF20) is a neurotrophic factor preferentially expressed in the substantia nigra of rat brain and could be involved in dopaminergic neurons survival. Recently, a strong genetic association has been found between FGF20 gene and the risk of suffering from Parkinson's disease (PD). Our aim was to replicate this association in two independent populations. METHODS: Allelic, genotypic, and haplotype frequencies of four biallelic polymorphisms were assessed in 151 sporadic PD cases and 186 controls from Greece, and 144 sporadic PD patients and 135 controls from Finland. RESULTS: No association was found in any of the populations studied. CONCLUSION: Taken together, these findings suggest that common genetic variants in FGF20 are not a risk factor for PD in, at least, some European populations

Parental diabetes status reveals association of mitochondrial DNA haplogroup J1 with type 2 diabetes

<p>Abstract</p> <p>Background</p> <p>Although mitochondrial dysfunction is consistently manifested in patients with Type 2 Diabetes mellitus (T2DM), the association of mitochondrial DNA (mtDNA) sequence variants with T2DM varies among populations. These differences might stem from differing environmental influences among populations. However, other potentially important considerations emanate from the very nature of mitochondrial genetics, namely the notable high degree of partitioning in the distribution of human mtDNA variants among populations, as well as the interaction of mtDNA and nuclear DNA-encoded factors working in concert to govern mitochondrial function. We hypothesized that association of mtDNA genetic variants with T2DM could be revealed while controlling for the effect of additional inherited factors, reflected in family history information.</p> <p>Methods</p> <p>To test this hypothesis we set out to investigate whether mtDNA genetic variants will be differentially associated with T2DM depending on the diabetes status of the parents. To this end, association of mtDNA genetic backgrounds (haplogroups) with T2DM was assessed in 1055 Jewish patients with and without T2DM parents ('DP' and 'HP', respectively).</p> <p>Results</p> <p>Haplogroup J1 was found to be 2.4 fold under-represented in the 'HP' patients (p = 0.0035). These results are consistent with a previous observation made in Finnish T2DM patients. Moreover, assessing the haplogroup distribution in 'DP' versus 'HP' patients having diabetic siblings revealed that haplogroup J1 was virtually absent in the 'HP' group.</p> <p>Conclusion</p> <p>These results imply the involvement of inherited factors, which modulate the susceptibility of haplogroup J1 to T2DM.</p

Genome Digging: Insight into the Mitochondrial Genome of Homo

A fraction of the Neanderthal mitochondrial genome sequence has a similarity with a 5,839-bp nuclear DNA sequence of mitochondrial origin (numt) on the human chromosome 1. This fact has never been interpreted. Although this phenomenon may be attributed to contamination and mosaic assembly of Neanderthal mtDNA from short sequencing reads, we explain the mysterious similarity by integration of this numt (mtAncestor-1) into the nuclear genome of the common ancestor of Neanderthals and modern humans not long before their reproductive split.Exploiting bioinformatics, we uncovered an additional numt (mtAncestor-2) with a high similarity to the Neanderthal mtDNA and indicated that both numts represent almost identical replicas of the mtDNA sequences ancestral to the mitochondrial genomes of Neanderthals and modern humans. In the proteins, encoded by mtDNA, the majority of amino acids distinguishing chimpanzees from humans and Neanderthals were acquired by the ancestral hominins. The overall rate of nonsynonymous evolution in Neanderthal mitochondrial protein-coding genes is not higher than in other lineages. The model incorporating the ancestral hominin mtDNA sequences estimates the average divergence age of the mtDNAs of Neanderthals and modern humans to be 450,000-485,000 years. The mtAncestor-1 and mtAncestor-2 sequences were incorporated into the nuclear genome approximately 620,000 years and 2,885,000 years ago, respectively.This study provides the first insight into the evolution of the mitochondrial DNA in hominins ancestral to Neanderthals and humans. We hypothesize that mtAncestor-1 and mtAncestor-2 are likely to be molecular fossils of the mtDNAs of Homo heidelbergensis and a stem Homo lineage. The d(N)/d(S) dynamics suggests that the effective population size of extinct hominins was low. However, the hominin lineage ancestral to humans, Neanderthals and H. heidelbergensis, had a larger effective population size and possessed genetic diversity comparable with those of chimpanzee and gorilla