			Home About us Contact

Dominant Family (dominant + family)

Distribution by Scientific Domains

Life Sciences	66%

Selected Abstracts

Does designation of protected areas ensure conservation of tree diversity in the Sudanian dry forest of Burkina Faso?

AFRICAN JOURNAL OF ECOLOGY, Issue 2 2010
Souleymane Paré
Abstract The importance of conservation status of the forest (protected versus unprotected) at two sites with differing human population density (high versus low) on the tree diversity of a Sudanian dry forest in Burkina Faso was studied. All woody species were recorded in 127 circular plots (area = 456.16 m2), and density, dominance, frequency, importance value indices and a variety of diversity measures were calculated to assess the species composition, structure and heterogeneity. A total of 69 species, representing 26 families and 52 genera, were found. Combretaceae, Leguminosae subfamily Caesalpinioideae and Rubiaceae were the dominant families. Neither human pressure nor forest conservation status significantly influenced the tree species richness. Stem density and basal area were significantly higher at the site with high population density than otherwise. Fisher's diversity index revealed the unprotected forest at the site with low population density as the most diverse. We identified species with high conservation importance that should be enriched to maintain a viable population size. In conclusion, the current designation of protected areas seems inefficient at ensuring the conservation of tree diversity in the forest reserve. Thus, participatory conservation programme should be initiated. Résumé À deux endroits où la densité de population humaine est différente (forte versus faible), nous avons étudié l'importance du statut de conservation de la forêt (protégée ou non) pour la diversité d'une forêt soudanienne sèche du Burkina Faso. On a enregistré toutes les espèces ligneuses sur 127 parcelles circulaires (superficie = 456,16 m²), et on a calculé la densité, la dominance, les indices de valeurs d'importance value et une variété de mesures de diversité pour évaluer la composition, la structure et l'hétérogénéité des espèces. On a découvert un total de 69 espèces, représentant 26 familles et 52 genres. Les familles dominantes étaient Combretaceae, Leguminosae de la sous-famille Caesalpinioideae, et Rubiaceae. Ni la pression humaine, ni le statut de conservation des forêts n'influençaient significativement la richesse en espèces d'arbres. La densité des troncs et la surface terrière à la base étaient significativement plus élevées sur le site à forte densité de population. L'indice de diversité de Fisher a permis de révéler que la forêt non protégée du site à faible densité de population était la plus diversifiée. Nous avons identifié des espèces de haute valeur de conservation qui devraient être enrichies pour préserver une taille de population viable. En conclusion, la désignation actuelle d'aires protégées semble inefficace pour assurer la conservation de la diversité des arbres dans la réserve forestière. Donc, il faudrait initier un programme de conservation participative. [source]

Bilateral striopallidodentate calcinosis: Clinical characteristics of patients seen in a registry

MOVEMENT DISORDERS, Issue 2 2001
Bala V. Manyam MD
Abstract Clinical features in bilateral striopallidodentate calcinosis (BSPDC), popularly referred to as Fahr's disease (five autosomal dominant families and eight sporadic cases, n = 38), recruited through a registry, are reported. Applying uniform criteria, cases reported in the literature (n = 61) were combined for detailed analysis. The mean (± S.D.) age of Registry patients was 43 ± 21 and that of literature was 38 ± 17. In combined data set (n = 99), 67 were symptomatic and 32 were asymptomatic. Of the symptomatic, the incidence among men was higher compared with women (45:22). Movement disorders accounted for 55% of the total symptomatic patients. Of the movement disorders, parkinsonism accounted for 57%, chorea 19%, tremor 8%, dystonia 8%, athetosis 5%, and orofacial dyskinesia 3%. Overlap of signs referable to different areas of central nervous system (CNS) was common. Other neurologic manifestations included: cognitive impairment, cerebellar signs, speech disorder, pyramidal signs, psychiatric features, gait disorders, sensory changes, and pain. We measured the total volume of calcification using an Electronic Planimeter and Coordinate Digitizer. Results suggest a significantly greater amount of calcification in symptomatic patients compared to asymptomatic patients. This study suggests that movement disorders are the most common manifestations of BSPDC, and among movement disorders, parkinsonism outnumber others. © 2001 Movement Disorder Society. [source]

Faunal makeup of wild bees and their flower utilization in a semi-urbanized area in central Japan

ENTOMOLOGICAL SCIENCE, Issue 2 2006
Masaki HISAMATSU
Abstract The species composition of wild bees and their flower utilization patterns were surveyed from April to November in 1996 in a semi-urbanized area adjacent to Sugao Marsh, Ibaraki, central Japan. A total of 750 individuals belonging to 43 species in six families were collected. The most dominant family was Halictidae, for which 13 species and 251 individuals were collected. The most dominant species was Colletes patellatus (120 individuals) of the Colletidae. The results at Sugao were compared with those obtained from three other areas of Ibaraki Prefecture, which have similar climatic conditions, yet have different environmental characteristics in terms of human impact. The four sites in Ibaraki can be classified into two groups: the first comprising Sugao and Mito in cultivated and/or human-dwelling areas, and the second comprising Yamizo and Gozen'yama, in forest areas with more natural elements. The number of species at Sugao was the smallest among the four study sites. On the other hand, the values for species evenness at Sugao were the second-highest of the four study sites. These findings show that the different characteristics of different bee communities reflect their local environmental conditions, including their floral compositions. The bees visited 36 flower species in 20 families, and 70.7% of all individuals studied visited Compositae flowers. The heavy utilization of composite flowers is possibly because of the existence of a simplified flora consisting of a few dominant composite plant species. Among these plants, Solidago altissima and Lactuca indica made large contributions to supporting autumn bees, especially Colletes patellatus and Colletes perforator, which are solitary and oligolectic on Compositae. [source]

Corporate Governance in India

JOURNAL OF APPLIED CORPORATE FINANCE, Issue 1 2008
Rajesh Chakrabarti
The Indian corporate governance system has both supported and held back India's ascent to the top ranks of the world's economies. While on paper the country's legal system provides some of the best investor protection in the world, enforcement is a major problem, with overburdened courts and significant corruption. Ownership remains concentrated and family business groups continue to be the dominant business model, with significant pyramiding and evidence of tunneling activity that transfers cash flow and value from minority to controlling shareholders. But for all its shortcomings, Indian corporate governance has taken major steps toward becoming a system capable of inspiring confidence among institutional and, increasingly, foreign investors. The Securities and Exchanges Board of India (SEBI), which was established as part of the comprehensive economic reforms launched in 1991, has made considerable progress in becoming a rigorous regulatory regime that helps ensure transparency and fair practice. And the National Stock Exchange of India, also established as part of the reforms, now functions with enough efficiency and transparency to be generating the third-largest number of trades in the world, just behind the NASDAQ and NYSE. Among more recent changes, the enactment of Sarbanes,Oxley type measures in 2004,which includes protections for minority shareholders in family- or "promoter"-led businesses,has contributed to recent increases in institutional and foreign stock ownership. And while family- and government-controlled business groups continue to be the rule, India has also seen the rise of successful companies like Infosys that are free of the influence of a dominant family or group and have made the individual shareholder their central governance focus. [source]

Floristic inventory and diversity assessment of a lowland African Montane Rainforest at Korup, Cameroon and implications for conservation

AFRICAN JOURNAL OF ECOLOGY, Issue 3 2010
Innocent Ndoh Mbue
Abstract Twenty modified-Whittaker plots were stratified at different sampling locations from February to May of 2008 in the central zone of Korup National Park, Cameroon. Our interest was to assess floristic diversity and investigate their relationship with environmental variables. Diversity profiles and rank abundance,curves were used for diversity analysis while canonical correspondence analysis and species,response curves were used to investigate the relationships between the response and explanatory variables. Of the 66 families identified, the Rubiaceae (999 species) were the most abundant. The Sterculiaceae (basal area = 10.482 m2 ha,1) were the dominant family, while the co-dominant families included the Ebenaceae (basal area = 9.092 m2 ha,1) and the Euphorbiaceae (basal area = 8.168 m2 ha,1). Soil variables explained 54.3% of total variation in family distribution. Canonical axes were related to different environmental gradients: axis1 was related to increasing canopy cover (r = 0.6951); axis 2, increasing Magnesium (r = 0.8465) and effective cation exchange capacity (r = 0.5899); axis 3, increasing effective cation exchange capacity (r = 0.5536); while axis 4, increasing Phosphorus concentration (r = 0.5232). Our results demonstrate the advantage which diversity profiles have over single or combination of indices, and the importance of using a combination of methodologies in diversity analysis. Résumé De février à mai 2008, vingt parcelles de Whittaker modifié ont été stratifiées à différents sites d'échantillonnage dans la zone centrale du Parc National de Korup, au Cameroun. Nous voulions évaluer la diversité floristique et étudier son lien avec diverses variables environnementales. Nous avons employé des profils de diversité et des courbes de rangs d'abondance pour l'analyse de la diversité, tandis que nous utilisions une analyse canonique des correspondances et des courbes de réponse des espèces pour étudier les relations entre les réponses et les variables explicatives. Sur les 66 familles identifiées, les Rubiacées (999 espèces) étaient les plus abondantes. Les Sterculiacées (surface basale = 10,482 m2 ha,1) étaient la famille dominante et, parmi les familles co-dominantes, il y avait les Ebénacées (surface basale = 9,092 m2 ha,1) et les Euphorbiacées (surface basale = 8,168 m2 ha,1). Des variables du sol expliquaient 54,3% de la variation totale de la distribution des familles. Les axes canoniques ont été liés aux différents gradients environnementaux; l'axe 1 était liéà une couverture croissante de la canopée (r = 0,6951); l'axe 2 à une augmentation du magnésium (r = 0,8465) et à la capacité réelle d'échange de cations (r = 0,5899); l'axe 3 à une capacité réelle croissante d'échanges de cations (r = 0,5536); et l'axe 4 à une concentration croissante en phosphore (r = 0,5532). Nos résultats montrent l'avantage que les profils de diversité ont sur des indices uniques ou combinés et l'importance d'utiliser une combinaison de méthodologies dans une analyse de diversité. [source]

Composition and distribution of vascular epiphytes in a tropical semideciduous forest, Ghana

AFRICAN JOURNAL OF ECOLOGY, Issue 4 2009
Patrick Addo-Fordjour
Abstract The composition and distribution of vascular epiphytes were studied in two 1-ha plots in the KNUST Botanic garden, Ghana. One-hectare plot each was randomly set up in secondary and cultivated forests for the identification and enumeration of trees and shrubs (,10 cm dbh), and epiphytes. Each tree was carefully examined, noting the presence, positions and life-forms of all epiphytes. Twenty-nine epiphyte (29) species belonging to fourteen genera and eleven families were identified in the study. These were hosted by 48 tree species and occurred in three life-forms: hemi-epiphytes (45%), casual epiphytes (45%) and true epiphytes (10%). The vascular epiphyte species made up 25.7% of all the identified plant species (excluding herbs and climbers) encountered. Host species (P < 0.001), habitat (P = 0.001) and their interaction (P < 0.001) had strong effects on epiphyte composition in the forests. Moraceae was the most dominant family (44.8%), while Nephrolepis undulata J. Sm. and N. biserrata (Sw.) Scott. were the commonest species of epiphytes. In terms of vertical distribution, most epiphytes were located on the trunk, while a few occurred in the canopy. Résumé On a étudié la composition et la distribution d'épiphytes vasculaires dans deux parcelles d'un hectare, dans le Jardin botanique de la KNUST, au Ghana. Chaque parcelle d'un hectare fut créée au hasard dans des forêts secondaire et cultivée pour y identifier et faire la liste des arbres et des arbustes (,10 cm dbh). Chaque arbre fut soigneusement examiné, et l'on a noté la présence, l'emplacement et les formes vivantes de tous les épiphytes. Vingt-neuf (29) espèces d'épiphytes appartenant à 14 genres et à 11 familles ont été identifiées au cours de cette étude. Elles croissaient sur 48 espèces d'arbres et se présentaient sous trois formes vivantes, hémi-épiphytes (45%), épiphytes opportunistes (45%) et épiphytes vrais (10%). Les espèces vasculaires d'épiphytes représentaient 25,7% de toutes les espèces végétales identifiées (à l'exclusion des herbacées et des plantes grimpantes). Les espèces hôtes (P < 0,001), l'habitat (P = 0,001) et leur interaction (P < 0,001) avaient un effet très net sur la composition des épiphytes dans les forêts. Les Moraceae étaient la famille dominante (44,8%) et Nephrolepis undulata J. Sm. et N. biserrata (Sw.) Scott étaient les espèces d'épiphytes les plus communes. En termes de distribution verticale, la plupart des épiphytes se situaient sur les troncs et quelques-uns croissaient dans la canopée. [source]