Flore et végétation actuelles de l’Afrique du nord, leur signification en fonction de l’origine, de Involution et des migrations des flores et structures de végétation passées

Bothalia ◽  
1983 ◽  
Vol 14 (3/4) ◽  
pp. 411-416 ◽  
Author(s):  
P. Quézel

PRESENT VEGETATION AND FLORA OF NORTHERN AFRICA, THEIR MEANING IN RELATION TO THEIR ORIGIN, EVOLUTION AND MIGRATIONS OF FLORAS AND THE STRUCTURES OF PAST VEGETATION In the light of recent works and biogeographic synthesis, the Mediterranean flora appears more and more as a heterogeneous entity, reflecting, to a great extent, the palaeogeographic and palaeoclimatic history of the region. In particular, the co-existence of elements of southern stock and of northerly elements, presently points to the possibilities of exchange which occurred very early in the Tertiary between the Gondwanian type of floras or the less  tropical types and the Laurasian floras.The tropical elements are numerous and can be linked to various entities according to their age; a pantropical entity comprising in particular, Tetraclinis and Warionia, but also various families, is common to all the tropical regions and, without any doubt, contemporary with the dismemberment of Gondwana; a north-tropical entity peculiarly common to California and the Mediterranean region; a palaeotropical entity strongly heterogeneous and complex. One finds there: —  thermophilous sclerophyll types often linked to the African rainforest species, — old xerophilous types, distributed in South Africa and north of the Equator (randflora), — endemic taxa of high African mountains, showing affinities with Ethiopian species or of the high African mountains, —  taxa more recently arrived or even common sahelian species settled during the last pluvial. The elements of extratropical stock are composed of autochthonal or Mediterraneo-Tertiary elements, and of northern elements. The Mediterraneo-Tertiary elements are the remnants of differentiated floras generally in situ on the banks of the Tethys and on the micro-plates which occur there. The role of the Iberian micro-plate is particularly important in the western Magreb. It is advisable to associate them with various species belonging to the Irano-touranian and Saharo-Arab stocks, whose settlement is often recent. An oro-Mesogean entity is particularly important and brings together the endemo-vicariant taxa generally occurring from the Atlas to the western Himalayas. The northern elements bring together a mesothermal entity, a remnant o f the pre-glacial Lauresian floras, poorly represented in north Africa, a microthermal northern entity generally comprising species recently established and a north-alpine entity contemporary with the last glaciations, extremely localized on the high Atlas mountains. Finally, the origin of the main characteristic formations of the Mediterranean stages is examined and discussed.

2020 ◽  
Vol 54 (2) ◽  
pp. 309-313
Author(s):  
Harun Rasiah

AbstractTeaching the history of the modern Middle East and North Africa at a small liberal arts university offered an opportunity to address student demands to “decolonize the curriculum.” As the survey course comes under increasing scrutiny, we asked where exactly is the Middle East located in our political imagination today? This essay focuses on the role of maps in rethinking geographic frameworks by using a seaborne perspective, that of the Mediterranean, Arabian and Red Seas (MARS) in contrast to the familiar Middle East and North Africa (MENA).


Author(s):  
P.L. Cottrell

This section of the journal is comprised of essays exploring the local maritime history of Liverpool and Merseyside. P.L. Cottrell studies Merseyside trade with the Mediterranean; Frank Neal considers the organisation of Liverpudlian ship carpenters and their impact on shipbuilding; Adrian Jarvis examines the role of Alfred Jones in Liverpool's maritime history; and Michael Stammers discusses Professor Davies' extensive study of Liverpool's nautical archaeology.


2019 ◽  
Vol 12 (5) ◽  
pp. 582-585
Author(s):  
Leslie Hakim-Dowek

As in Marianne Hirsch’s (2008) notion of ‘devoir de memoire’, this poem-piece, from a new series, uses the role of creation and imagination to strive to ‘re-activate and re-embody’ distant family/historical transcultural spaces and memories within the perspective of a dispersed history of a Middle-Eastern minority, the Sephardi/Jewish community. There is little awareness that Sephardi/Jewish communities were an integral part of the Middle East and North Africa for many centuries before they were driven out of their homes in the second half of the twentieth century. Using a multi-modal approach combining photography and poetry, this photo-poem series has for focus my female lineage. This piece evokes in particular the memory of my grandmother, encapsulating many points in history where persecution and displacement occurred across many social, political and linguistic borders.


Author(s):  
Samir Casseb ◽  
Karla de Melo

Dengue is an acute febrile disease caused by a virus of the genus Flavivirus, family Flaviviridae, endemic in tropical regions of the globe. The agent is a virus with single-stranded RNA, classified into four distinct dengue virus (DENV) serotypes: DENV-1, DENV-2, DENV-3, and DENV-4. The host’s innate and adaptive immune responses play an essential role in determining the natural history of viral infections, especially in dengue. In this context, it has observed in recent years that the presence of RNA interference (RNAi) in viral infection processes is increasing, as well as immune defense. The context microRNAs (miRNAs) go for stood out, as their presence during viral infection, both in the replication of the virus and in the defense against these infections, becomes increasingly noticeable, therefore, making it increasingly necessary to better understand the role of these small RNAs within viral infection by DENV and what their consequences are in aggravating the consequences of patients affected by this disease.


2020 ◽  
Author(s):  
Glenda Garelli ◽  
Martina Tazzioli

Abstract This article engages with the centrality that the push–pull theory regained in the context of border deaths in the Mediterranean Sea and particularly as part of the debate against the criminalization of nongovernment organizations (NGOs’) rescue missions at sea. The article opens by illustrating the context in which the push–pull theory re-emerged—after having been part of migration studies’ history books for over a decade—as part of an effort to defend non-state actors engaged in rescue missions in the Mediterranean Sea against an aggressive campaign of illegalilzation conducted by European states. We then take a step back to trace the history of the push–pull theory and its role as a foil for critical migration studies in the past 20 years. Building on this history, the article then turns to interrogating the epistemic and political outcomes that result from bringing evidence against the NGOs’ role as pull factors for migrants. The article closes by advocating for a transformative, rather than evidencing, role of critical knowledge in the current political context where migrants and actors who fight against border deaths are increasingly criminalized.


2012 ◽  
Vol 46 (1) ◽  
pp. 47-53
Author(s):  
Edmund Burke

There is something seriously flawed about models of social change that posit the dominant role of in-built civilizational motors. While “the rise of the West” makes great ideology, it is poor history. Like Jared Diamond, I believe that we need to situate the fate of nations in a long-term ecohistorical context. Unlike Diamond, I believe that the ways (and the sequences) in which things happened mattered deeply to what came next. The Mediterranean is a particularly useful case in this light. No longer a center of progress after the sixteenth century, the decline of the Mediterranean is usually ascribed to its inherent cultural deficiencies. While the specific cultural infirmity varies with the historian (amoral familism, patron/clientalism, and religion are some of the favorites) its civilizationalist presuppositions are clear. In this respect the search for “what went wrong” typifies national histories across the region and prefigures the fate of the Third World.


Author(s):  
Terje Tvedt

To understand the role of the modern Nile in African history, it is first necessary to have familiarity with the premodern “natural” Nile, including both its hydrology and societal importance. It is well known that no river basin in the world has a longer, more complex, and more eventful history. The Nile water issue in modern times is a history of how economic and political developments in East and North Africa have been fundamentally shaped by the interconnectedness of the Nile’s particular physical and hydrological character; the efforts of adapting to, controlling, using, and sharing the waters of the river; and the different ideas and ambitions that political leaders have had for the Nile.


2019 ◽  
Vol 93 (5) ◽  
pp. 945-965 ◽  
Author(s):  
Abouchouaib Belahmira ◽  
Joerg W. Schneider ◽  
Frank Scholze ◽  
Hafid Saber

AbstractThe Late Pennsylvanian (Kasimovian, early Stephanian) sub- to perimontaneous Souss basin, situated in the present-day southwestern High Atlas mountains of Morocco, contains the hitherto only known late Paleozoic entomofauna from North Africa, which is simultaneously also the southernmost Euramerican entomofauna. The present study provides descriptions, identifications, and revisions of several species belonging to the genera Phyloblatta and Anthracoblattina (family Phyloblattidae) and of the genus Compsoblatta (family Compsoblattidae). A relatively large number of well-preserved Phyloblatta forewings, compared with congeneric species from several insect localities in Europe and North America, permits insights into the individual, intraspecific, and interspecific variability of the venation pattern as indispensable base for the description of the new specimens and the revision of several older species. The Souss insect beds cover a wide range of potential habitats. They are situated in different paleogeographical positions within the Souss basin and scattered across a 900 m thick succession of sediments. The single insect beds represent different sedimentary and biotic subenvironments from swamps and mires to shallow and deep lakes within a fluvial-dominated megaenvironment.


1986 ◽  
Vol 95 (6) ◽  
pp. 603-607 ◽  
Author(s):  
Haskins Kashima ◽  
Francis Kuhajda ◽  
Phoebe Mounts ◽  
Mark Loury

We have undertaken a retrospective study to investigate the role of human papillomavirus (HPV) in the development of laryngeal carcinoma in situ (CIS). Sixty paraffin-embedded tissue specimens, collected from 20 patients with a history of laryngeal CIS, were examined for the presence of HPV capsid antigen. All but four individuals were men, with an average age at diagnosis of 64 years. An immunoperoxidase technique showed that 20 specimens from 14 patients contained detectable HPV capsid antigen. An independent evaluation for histopathologic features characteristic of HPV infection identified viral changes in the 14 patients as well as an additional two. No correlation was found between clinical course, as determined by histologic severity of vocal cord lesions, and presence of HPV. These results suggest that HPV should be considered an etiologic agent in the development of laryngeal CIS.


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