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The neural circuits that support human cognition are a topic of enduring interest. Yet, the lack of tools available to map human brain circuits has precluded our ability to trace the human and non-human primate connectome. We harnessed high-resolution connectomic, anatomic, and transcriptomic data to investigate the evolution and development of frontal cortex circuitry. We applied machine learning to RNA sequencing data to find corresponding ages between humans and macaques and to compare the development of circuits across species. We transcriptionally defined neural circuits by testing for associations between gene expression and white matter maturation. We then considered transcriptional and structural growth to test whether frontal cortex circuit maturation is unusually extended in humans relative to other species. We also considered gene expression and high-resolution diffusion MR tractography of adult brains to test for cross-species variation in frontal cortex circuits. We found that frontal cortex circuitry development is extended in primates, and concomitant with an expansion in cortico-cortical pathways compared with mice in adulthood. Importantly, we found that these parameters varied relatively little across humans and studied primates. These data identify a surprising collection of conserved features in frontal cortex circuits across humans and Old World monkeys. Our work demonstrates that integrating transcriptional and connectomic data across temporal dimensions is a robust approach to trace the evolution of brain connectomics in primates.Significance StatementWe lack appropriate tools to visualize the human brain connectome. We develop new approaches to study connections in the human and non-human primate brains. The integration of transcription with structure offers an unprecedented opportunity to study circuitry evolution. Our integrative approach finds corresponding ages across species and transcriptionally defines neural circuits. We used this information to test for variation in circuit maturation across species and found a surprising constellation of similar features in frontal cortex neural circuits across humans and primates. Integrating across scales of biological organization expands the repertoire of tools available to study connections in primates, which opens new avenues to study connections in health and diseases of the human brain.

One major reason for extremely low production of tomato in Ghana is that the length of the growing season last only for a few months due to the high temperature influx during the remaining months. The temperatures recorded during these months are above the optimum for tomato flowering and fruiting and this consequently affects yield. To solve this problem a number management practices may be undertaken such has growing heat tolerant tomato varieties or providing shade to mitigate the devastating effect of high temperatures. Therefore the present study was conducted outside the normal growing season from June to October, which has a mean temperature of 23°C. Heat tolerant tomato cultivars were grown from April to July with a mean temperature of 25°C to evaluate their performance under these conditions and to assess the effect of shading on the production of one of the genotypes. Fruiting percentage was significantly lower in exotic hybrids compared to a local variety. Different genotypes showed no differences in the production of viable pollen. Shading decreased final shoot and root biomass by 67 and 47%, respectively, whiles fruit yield was not affected. Also among cultivars yields were similar. One major reason for extremely low production of tomato in Ghana is that the length of the growing season last only for a few months due to the high temperature influx during the remaining months. The temperatures recorded during these months are above the optimum for tomato flowering and fruiting and this consequently affects yield. To solve this problem a number management practices may be undertaken such has growing heat tolerant tomato varieties or providing shade to mitigate the devastating effect of high temperatures. Therefore the present study was conducted outside the normal growing season from June to October, which has a mean temperature of 23°C. Heat tolerant tomato cultivars were grown from April to July with a mean temperature of 25°C to evaluate their performance under these conditions and to assess the effect of shading on the production of one of the genotypes. Fruiting percentage was significantly lower in exotic hybrids compared to a local variety. Different genotypes showed no differences in the production of viable pollen. Shading decreased final shoot and root biomass by 67 and 47%, respectively, whiles fruit yield was not affected. Also among cultivars yields were similar.

We report on a study to determine the decomposition and nutrient release patterns of Pueraria phaseoloides and Flemingia macrophylla leaf residues under two rainfall regimes in southern Cameroon. Fresh leaf material of the two legume species were put in litter bags and placed on the soil surface for 120 days at Ngoumou (high rainfall) and Nkometou (low rainfall). Mass loss of the leaf residue was faster in P. phaseoloides than F. macrophylla such that half-lives ranged from 9.0 - 9.5 weeks for P. phaseoloides and 14.6 - 20.2 weeks for F. macrophylla. Per cent leaf mass remaining was greater (p < 0.05) at Ngoumou than at Nkometou with mean half-lives being 14.6 and 12.1 weeks, respectively. The release of nutrients (N, P, K, Ca and Mg) was faster and in greater quantities in P. phaseoloides than F. macrophylla. More than half of the constituent N in P. phaseoloides was released in 9 weeks. Generally, half of K released from either legume species was within the first 5 weeks. The rate of release of each constituent nutrient was faster at Ngoumou than at Nkometou. The study concluded that P. phaseoloides had the largest amounts and rates of nutrient releases and therefore could ensure greater nutrient availability to associated crops. Banful, B., Hauser, S., Kumaga, F., Ofori, K. & Ndango, R. Les Modèles de la Décomposition et le Transfert des Nutriments dans le Cas de Pueraria Phaseoloides et Flemingia Macrophylla sous deux Régimes Pluvieux. Nous faisons notre réportage sur une étude pour déterminer les modèles de la décomposition et le transfert des nutriments dans le cas de Pueraria Phaseoloides et flemingia macrophylla sous deux régimes pluvieux au sud du Caméroon. Frais matériau de feuille des espèces légumineuses étaient mis dans des boîtes litières et placés sur la superficie du sol pour 120 jours à Ngoumou (pluie intenses) et Nkometou (pluies non intenses). La perte en masse des feuilles était plus rapide en P. phaseoloides que F. macrophylla tel que “démi vies” ont rangé entre 9.0 et 9.5 semaines dans le cas de P. phageoloides et 14.6 et 12.1 semaines dans le cas de F. macrophylla. Le pourcentage de feuille qui reste était plus grand à Nkometou avec un moyen “démi-vies” de 14.6 et 12.1 semaines respectivement. Le transfert des nutriments (N,P,K, Ca et Mg) était plus rapide et en grande qualité dans le cas de p. phaseoloides que F. macrophylla. Plus de la moitié des composants N dans P. phaseoloides étaient transférés en 9 semaines. Généralement, la moitié de K transféré de chaque espèce légumineuses était dans la première 5 semaines. Parmi les villages, le niveau de transfert de chaque composant nutrif était plus rapide à Ngoumou qu\' à Nkometou. L\'étude a conclu que pueraria phaseoloides possèdait un niveau plus élevé de transfert des nutriments et donc capable d\'assurer la disponibilité des nutriments aux cultures associeées en grande quantité. Keywords: Rainfall, mass loss, nutrient loss, planted fallows. Agricultural and Food Science Journal of Ghana Vol. 6 2007 pp. 485-500

Forty-five cowpea accessions randomly selected from cowpea germplasm from four major cowpea-producing regions of Ghana, namely Upper East, Upper West, Northern and Eastern regions, were evaluated to study variability in some quantitative characters. Variability within regions was not significant, but there were significant differences among the regions for all the characters studied. The accessions from Northern Region were the first to flower and mature, while those from Upper East Region were the last to flower and mature. The number of pods per plant and seed yield per plant had rather large and similar ranges. A large proportion of the observed variability in pod and seed character was due to genetic differences, especially for 100-seed weight. However, the lowest variability among accessions, except for the 100-seed weight, was recorded for the Eastern Region. Accessions from Upper East Region had the largest variability for most of the characters. This identifies the Upper East Region as a potential source of material for cowpea improvement. Variabilité en quelques caractères quantitatifs des variétés des dolique (Vigna unguiculata (L.) Walp) au Ghana Résumé Quarante-cinq accessions de dolique sélectionnées au hasard de germeplasme de dolique de quatre principales régions productrices de dolique au Ghana, à savoir, les regions d'Upper East, Upper West, Northern et Eastern étaient évaluées pour étudier la variabilité en quelques caractères quantitatifs. La variabilité à l'intérieur des régions n'était pas considérable, mais il y avait des différences considérables parmi les régions pour tous les caractères étudiés. Les accesions de Northern Region étaient les premières à fleurir et mûrir, alors que celles d'Upper East Region étaient les dernières à fleurir et mûrir. Le nombre de cosse par plante et le rendement de graine par plante avaient plutôt des variations grandes et semblables. Une grande partie de la variabilité observée dans les caractères de cosse et de graine était provoquée par des différences génétiques surtout pour le poids de 100-graine. Toutefois, la plus basse variabilité parmi les accessions, à l'exception du poids de 100-graine, était enregistrée pour Eastern Region. Les accessions d'Upper East Region avaient la plus grande variabilité pour la plupart des caractères. Ceci identifie Upper East Region comme une source potentielle de matiriel pour l'amélioration de dolique. Ghana Jnl agric. Sci. Vol.33(2) 2004: 165-170