scholarly journals Biological and Ecological Traits of Terrestrial Arthropods in North-West Morocco

2022 ◽  
Vol 23 (1) ◽  
pp. 252-263
Author(s):  
Elharche Hanae ◽  
Chavanon Guy ◽  
Dahmani Jamila ◽  
Bedoui Imane ◽  
Kaioua Samiha ◽  
...  
Author(s):  
Bailack Kevin Mbuh ◽  
Mbanga Lawrence Akei

The lucid engagements of stakeholders in land management is an essential strategy in circumventing the stakes of land utilisation. This is symptomatic in ecumenes of intricate ecological traits with diverse stakeholders’ management interests. Bui Division of the North West Region of Cameroon, a citadel of stakeholders enmeshed and is manning their respective lands with signatures of rare plausible interaction options in a decentralisation framework. As such, the study sought to assess the stakeholders’ interaction options for land management in Bui Division. A historical and comparative research designs were used to obtain primary and secondary data from 1971-2021. This was through questionnaires, formal and informal interviews from 16.9% of population in 505 households and direct observations with consultation of published and unpublished documents. Data was analysed using inferential statistics with the Anova Test at 0.05 at a critical level and a df of 7 to determine the significant differences in stakeholders’ interaction options for land management. The results reveal the calculated values of 0.9, 8, 3.9, 3.6 and 8.3 higher than the tabulated ratios of 0.65, 0.000, 0.001, 0.002 and 0.000 respectively. This indicates that there were significant differences in stakeholders’ interaction options in land management based on stakeholders’ activities and interests. Multiple stakeholders’ collaborative and participatory interaction options were positively apt in diverse sectors of land management. The study posits that participatory interaction through multi-stakeholders’ involvements and collaborations are the best options to minimise the deprived perceptions of under representation of some stakeholders in land management platforms in Bui Division.


2017 ◽  
Vol 122 (2) ◽  
pp. 286-300 ◽  
Author(s):  
Teresa L Silva ◽  
Cândida G Vale ◽  
Raquel Godinho ◽  
Amina Fellous ◽  
Yves Hingrat ◽  
...  

Abstract Conservation planning of threatened taxa relies upon accurate data on systematics, ecological traits and suitable habitats. The genus Gazella includes taxa with distinct morphologies and ecological traits, but close phylogenetic relationships. The North African Gazella cuvieri and Gazella leptoceros loderi share morphological and physiological characters but the former is darker and found in mountain areas, while the latter is lighter and associated with sand dunes. Here we aim to assess the genetic distinctiveness of these taxa, to characterize their ecological niches and to identify potential occurrence areas, by analysing 327 samples across North-West Africa. Phylogenetic analyses based on mitochondrial (CYTB) and five nuclear gene fragments (KCAS, LAC, SPTBN1, PRKCI and THYR) show that both taxa comprise a single monophyletic group. However, ecological niche-based modelling suggests that populations of these taxa occupy distinct geographic areas and specific environments. Predicted areas of sympatry were restricted, as a consequence of local sharp transitions in climatic traits. The lack of genetic differentiation between these taxa suggests they should be lumped into G. cuvieri, while ecological and morphological differences indicate they correspond to distinct ecotypes. Conservation planning of G. cuvieri should consider the preservation of both mountain and lowland ecotypes to maintain the overall adaptive potential of the species. This integrative approach provides valuable insights in identifying evolutionary units and should be extended to other gazelles.


Author(s):  
S. Shirahama ◽  
G. C. Engle ◽  
R. M. Dutcher

A transplantable carcinoma was established in North West Sprague Dawley (NWSD) rats by use of X-irradiation by Engle and Spencer. The tumor was passaged through 63 generations over a period of 32 months. The original tumor, an adenocarcinoma, changed into an undifferentiated carcinoma following the 19th transplant. The tumor grew well in NWSD rats of either sex at various ages. It was invariably fatal, causing death of the host within 15 to 35 days following transplantation.Tumor, thymus, spleen, and plasma from 7 rats receiving transplants of tumor at 3 to 9 weeks of age were examined with an electron microscope at intervals of 8, 15, 22 and 30 days after transplantation. Four normal control rats of the same age were also examined. The tissues were fixed in glutaraldehyde, postfixed in osmium tetroxide and embedded in Epon. The plasma was separated from heparanized blood and processed as previously described for the tissue specimens. Sections were stained with uranyl acetate followed by lead citrate and examined with an RCA EMU-3G electron microscope.


Author(s):  
Daryl A. Cornish ◽  
George L. Smit

Oreochromis mossambicus is currently receiving much attention as a candidater species for aquaculture programs within Southern Africa. This has stimulated interest in its breeding cycle as well as the morphological characteristics of the gonads. Limited information is available on SEM and TEM observations of the male gonads. It is known that the testis of O. mossambicus is a paired, intra-abdominal structure of the lobular type, although further details of its characteristics are not known. Current investigations have shown that spermatids reach full maturity some two months after the female becomes gravid. Throughout the year, the testes contain spermatids at various stages of development although spermiogenesis appears to be maximal during November when spawning occurs. This paper describes the morphological and ultrastructural characteristics of the testes and spermatids.Specimens of this fish were collected at Syferkuil Dam, 8 km north- west of the University of the North over a twelve month period, sacrificed and the testes excised.


1996 ◽  
Vol 26 (12) ◽  
pp. 1364-1370 ◽  
Author(s):  
R. S. H. Pumphrey ◽  
S. J. Stanworth
Keyword(s):  

2014 ◽  
Author(s):  
Roald Amundsen ◽  
Godfred Hansen
Keyword(s):  

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