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191.
The water quality of the Siluko River, Edo State, Nigeria was investigated from March to August 2015 to determine its suitability for drinking and usage for domestic purposes. Water samples collected from three stations were tested for thirteen physico-chemical parameters using standard analytical procedures. Temperature, phosphate and chloride were significantly different across the three stations. All other parameters, with the exception of turbidity, dissolved oxygen and phosphate, were within the permissible limits recommended by the Nigerian Standard for Drinking Water Quality (NSDWQ) and World Health Organization (WHO). Water Quality Index (WQI) values ranged from 11.24 to 16.15, indicating excellent water quality. While the quality of the water from the Siluko River is suitable for drinking and domestic usage, to prevent future deterioration of the water, it is recommended that the regulating authorities monitor effluents discharged into the river from human activities. 相似文献
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193.
Numbers of total, metabolically active, dormant or dead axillarybuds, and growth characteristics were determined before andafter controlled burnings in Stipa tenuis Phil., a native foragegrass of the Caldén District in central Argentina. One-hectareplots were burned on 25 Mar. (Burn 1) or 4 Apr. 1991 (Burn 2),or remained unburned (control). Bud metabolic activity was examinedusing the tetrazolium test and the vital stain Evans' blue. Before fire, more than 83% of the axillary buds on previous-seasonstems of S. tenuis were metabolically active in all treatments.After fire, previous-season stems that produced tiller in thecontrol and Burn 2 plots had more than 75% of the axillary budsalive, but those that did not produce them had more than 82%of their axillary buds dead in the burned areas. This high budmortality was associated with direct fire effects on the fateof buds; most dead buds showed visible signs of dehydration.Since more than 97% of the plant stem bases did not producetillers after fire, tiller number per plant was reduced (P <0·05) in the burned plots to fewer than 22% of valuesof controls. Plant mortality was 50% higher at the Burn 1 thanat the Burn 2 site probably because the first site had a 43%lower soil moisture content (P < 0·05). At the endof the growing season, however, a different set of S. tenuisplants at both burned sites had a similar tiller number anddry weight to controls. These plants were probably in areasof lighter fuel loads and exposed to a less intense fire.Copyright1993, 1999 Academic Press Stipa tenuis Phil., thin needlegrass, controlled burning, bud viability, axillary meristems, regrowth 相似文献
194.
Florencia Chiapero Ricardo H. Ferrari Agustín Guglielmetti María C. García Capocasa Juan M. Busso 《Zoo biology》2021,40(1):33-43
There is a growing ethical concern in modern society about animals' quality of life. We hypothesize that zoo visitors' perception of zoo animal welfare, particularly in the case of lesser anteaters, changes positively after listening to scientific information. Visitors observing active lesser anteaters in their enclosures at Córdoba Zoo (Argentina) were asked to respond to a questionnaire about animal welfare. The treatment group (T) answered the questionnaire after listening to a brief informative talk based on local scientific studies on lesser anteaters. The control group (C) answered the questionnaire without hearing the informative talk. Visitors (87.2%) considered biological, sanitary, and sociocultural aspects to be necessary conditions for optimum wild zoo‐housed animal welfare. The majority of visitors considered that natural surroundings provide the highest level of welfare for wild animals. Visitors in the T group ranked the zoo as providing a higher level of animal welfare than those in group C. In reference to management measurements, the T group agreed on the positive effect of the application of environmental enrichment (Likert Medians: C = 4 and T = 5; p = .0443). On the basis of their perception, most visitors in both groups stated that the lesser anteaters at Córdoba Zoo appeared to be in a good state of welfare. We interpret this as meaning that, what these Córdoba zoo visitors personally perceived while observing the lesser anteaters carried greater weight than what they learned from the informative talk, though the talk did slightly affect their opinion. 相似文献
195.
MS Nandhu Jes Paul Korah P Kuruvilla Anitha Malat Chinthu Romeo CS Paulose 《Journal of biomedical science》2011,18(1):5
Parkinson's disease is characterized by progressive cell death in the substantia nigra pars compacta, which leads to dopamine
depletion in the striatum and indirectly to cortical dysfunction. Increased glutamatergic transmission in the basal ganglia
is implicated in the pathophysiology of Parkinson's disease and glutamate receptor mediated excitotoxicity has been suggested
to be one of the possible causes of the neuronal degeneration. In the present study, the effects of serotonin, gamma-aminobutyric
acid and bone marrow cells infused intranigrally to substantia nigra individually and in combination on unilateral 6-hydroxydopamine
induced Parkinson's rat model was analyzed. Scatchard analysis of total glutamate and NMDA receptor binding parameters showed
a significant increase in Bmax (P < 0.001) in the cerebral cortex of 6-hydroxydopamine infused rat compared to control. Real Time PCR amplification of NMDA2B,
mGluR5, bax, and ubiquitin carboxy-terminal hydrolase were up regulated in cerebral cortex of 6-hydroxydopamine infused rats
compared to control. Gene expression studies of GLAST, ά-Synuclien and Cyclic AMP response element-binding protein showed
a significant (P < 0.001) down regulation in 6-OHDA infused rats compared to control. Behavioural studies were carried out
to confirm the biochemical and molecular studies. Serotonin and GABA along with bone marrow cells in combination showed reversal
of glutamate receptors and behaviour abnormality shown in the Parkinson's rat model. The therapeutic significance in Parkinson's
disease is of prominence. 相似文献
196.