scholarly journals Incidences of anthropogenic pressure on the degradation of the scrub of the western Algerian region (Tlemcen, case of Djebel Felloucene): qualitative and quantitative aspects

2021 ◽  
Vol 12 (3) ◽  
pp. 755-760
Author(s):  
Rachid Dahmani ◽  
Abdessamed Merzouk ◽  
Sid Ahmed Aouadj
2020 ◽  
Vol 7 (2) ◽  
pp. 88-97
Author(s):  
Aouadj Sid Ahmed ◽  
Nasrallah Yahia ◽  
Hasnaoui Okkacha ◽  
Khatir Hadj

AbstractThe forest of Doui Thabet is one of the forests of the Mounts of Saida (Western Algeria) which is experiencing a dynamic regressive. Located in the semi-arid bioclimatic stage, it is located at the edge of two phytogeographic sub-sectors: atlas Tellien Oranais (O3) and high plateau subsector (H1). Among the factors that threaten to curb this fragile and weakened ecosystem, in addition to drought and climate aridity and which has become a structural ecological phenomenon; the overgrazing is also a major limiting factor. This current study provides a qualitative and quantitative assessment of anthropogenic pressure exerted in this area zone. The methodology adopted in this study is that of Le Houerou (1969) and Montoya (1983), which it is based on the calculation of the annual needs of the herd in forage units, the estimate of the feed potential of production, the coefficient of overgrazing and in addition to the anthropogenic pressure index. The result of the forage balance in the forest rangelands of the studied area has a forage deficit (overload) of (96.64%) (a sylvopastoral imbalance), in addition to that, the coefficient of overgrazing is (92.3%) and the anthropogenic pressure index is very high (28). The conservation and the restoration of this area is a major concern in the face of global changes, taking into account their mode of reproduction and their dynamics, for the development of restoration strategies and more effective ways of protection.


Author(s):  
Halyna Humeniuk ◽  
Olena Voloshyn ◽  
Volodymyr Voloshyn

The anthropogenic pressure on aquatic ecosystems leads to a significant transformation of their quantitative and qualitative composition. Many rivers of Ukraine are polluted. The object of research was the surface waters of the rivers Pripyat and Turiya (Volyn region, Ukraine). Analysis of the qualitative and quantitative composition of toxicants (Cd, Pb) showed that the waters of the rivers have high level of pollution. A negative phenomenon in the studied reservoirs is a significant excess of concentrations of heavy metals: lead in 118 times and cadmium in 110 times in August.


2021 ◽  
Vol 71 ◽  
pp. 711-722
Author(s):  
Roberto Leonan M. Novaes ◽  
Don E. Wilson ◽  
Ricardo Moratelli

Abstract The genus Myotis comprises a diverse group of vesper bats with worldwide distribution. Twenty-eight neotropical species are currently recognized. Based on a morphological approach, we describe a new species of Myotis from the Uruguayan Pampas grasslands, an ecoregion under high anthropogenic pressure with a largely unknown bat fauna. Qualitative and quantitative morphological analyses support the recognition of the new species and we present a set of external and cranial diagnostic characters by comparing them with other neotropical Myotis species. The new species reassembles Myotis riparius, but can be distinguished by a set of qualitative and quantitative morphological traits, including its clearly bicolored dorsal fur, tricolored ventral fur, a pelage on the dorsal surface of uropatagium, sagittal crest lower, braincase lower in lateral view and overall smaller size.


Author(s):  
R.L. Price ◽  
T.K. Borg ◽  
L. Terracio ◽  
M. Nakagawa

Little is known about the temporal expression of extracellular matrix components (ECM) and its receptors during development of the heart. Recent reports have shown that ECM components undergo both qualitative and quantitative changes during development, and it is believed that ECM components are important in the regulation of cell migration and cell:cell and cell:ECM recognition and adhesion.Integrins are transmembrane glycoproteins which bind several ECM components on their external face and cytoskeletal elements on the cytoplasmic face. Laminin is a basement membrane component which has been recognized as an important site for cell adhesion. Both the integrins and laminin are expressed early in development and continue to be expressed in the adult heart. With their documented roles in cell recognition, and cell:cell and cell:ECM migration and adhesion these proteins appear to be important components in development of the heart, and their temporal expression may play a pivotal role in morphogenesis and myofibrillogenesis of the heart.


Author(s):  
Jerrold L. Abraham

Inorganic particulate material of diverse types is present in the ambient and occupational environment, and exposure to such materials is a well recognized cause of some lung disease. To investigate the interaction of inhaled inorganic particulates with the lung it is necessary to obtain quantitative information on the particulate burden of lung tissue in a wide variety of situations. The vast majority of diagnostic and experimental tissue samples (biopsies and autopsies) are fixed with formaldehyde solutions, dehydrated with organic solvents and embedded in paraffin wax. Over the past 16 years, I have attempted to obtain maximal analytical use of such tissue with minimal preparative steps. Unique diagnostic and research data result from both qualitative and quantitative analyses of sections. Most of the data has been related to inhaled inorganic particulates in lungs, but the basic methods are applicable to any tissues. The preparations are primarily designed for SEM use, but they are stable for storage and transport to other laboratories and several other instruments (e.g., for SIMS techniques).


VASA ◽  
2012 ◽  
Vol 41 (1) ◽  
pp. 19-26 ◽  
Author(s):  
Hoerth ◽  
Kundi ◽  
Katzenschlager ◽  
Hirschl

Background: Nailfold capillaroscopy (NVC) is a diagnostic tool particularly useful in the differential diagnosis of rheumatic and connective tissue diseases. Although successfully applied since many years, little is known about prevalence and distribution of NVC changes in healthy individuals. Probands and methods: NVC was performed in 120 individuals (57 men and 63 women; age 18 to 70 years) randomly selected according to predefined age and sex strata. Diseases associated with NVC changes were excluded. The nailfolds of eight fingers were assessed according to standardized procedures. A scoring system was developed based on the distribution of the number of morphologically deviating capillaries, microhaemorrhages, and capillary density. Results: Only 18 individuals (15 %) had no deviation in morphology, haemorrhages, or capillary density on any finger. Overall 67 % had morphological changes, 48 % had microhaemorrhages, and 40 % of volunteers below 40 years of age and 18 % above age 40 had less than 8 capillaries/mm. Among morphological changes tortous (43 %), ramified (47 %), and bushy capillaries (27 %) were the most frequently altered capillary types. A semiquantitative scoring system was developed in such a way that a score above 1 indicates an extreme position (above the 90th percentile) in the distribution of scores among healthy individuals. Conclusions: Altered capillaries occur frequently among healthy individuals and should be interpreted as normal unless a suspicious increase in their frequency is determined by reference to the scoring system. Megacapillaries and diffuse loss of capillaries were not found and seem to be of specific diagnostic value.


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