Vegetative survival, akinete and zoosporangium formation and germination in some selected algae as affected by nutrients, pH, metals, and pesticides

2002 ◽  
Vol 47 (5) ◽  
pp. 527-534 ◽  
Author(s):  
S. C. Agrawal ◽  
U. Misra
Keyword(s):  
Vegetative Survival

Ultrastructure of Melosira resting cell rejuvenation

1984 ◽  
Vol 42 ◽  
pp. 734-735
Author(s):  
C. E. M. Bourne ◽  
L. Sicko-Goad
Keyword(s):  
Electron Microscopy ◽  
Lake Michigan ◽  
Light And Electron Microscopy ◽  
Resting Cells ◽  
Planktonic Diatoms ◽  
Resting Cell ◽  
Vegetative Survival ◽  
Cytological Changes ◽  
Recent Attention ◽  
Freshwater Diatom

Much recent attention has been focused on vegetative survival forms of planktonic diatoms and other algae. There are several reports of extended vegetative survival of the freshwater diatom Melosira in lake sediments. In contrast to those diatoms which form a morphologically distinct resistant spore, Melosira is known to produce physiological resting cells that are indistinguishable in outward morphology from actively growing cells.We used both light and electron microscopy to document and elucidate the sequence of cytological changes during the transition from resting cells to actively growing cells in a population of Melosira granulata from Douglas Lake, Michigan sediments collected in mid-July of 1983.

scholarly journals Vegetative survival

Anaesthesia ◽  
1989 ◽  
Vol 44 (7) ◽  
pp. 608-609
Author(s):  
S.Q.M. Tighe ◽  
C.R.G. Reid
Keyword(s):  
Vegetative Survival

Reproductive Behaviour of Natural Populations of Meadow Salsify (Tragopogon pratensis)

Weed Science ◽  
1996 ◽  
Vol 44 (1) ◽  
pp. 68-73 ◽  
Author(s):  
Meiqin QI ◽  
Mahesh K. Upadhyaya ◽  
Roy Turkington
Keyword(s):  
Seed Production ◽  
Natural Populations ◽  
Reproductive Behaviour ◽  
Plant Size ◽  
Bud Bank ◽  
Potential Fecundity ◽  
Juvenile Mortality ◽  
Crown Diameter ◽  
Vegetative Survival ◽  
Monocarpic Perennial

The reproductive characteristics of natural populations of meadow salsify were monitored between May 1990 and October 1991. Plants in even-aged populations did not produce seeds prior to the second winter and plants in uneven-aged populations died after seed production suggesting that meadow salsify at this site is a monocarpic perennial and not a true biennial. Delayed seed production may enhance abundance of this species by increasing the size of its bud bank. Plants of uneven-aged populations flowered over a range of root crown diameters; the percentage of plants bearing flowers increased with increasing root crown diameters. The minimum root crown diameter at which plants flowered in 1990 and 1991 was 0.2 and 0.6 cm respectively demonstrating that factor(s) other than plant size regulate flowering in this species. Seed production ranged between 100 to 850 seeds per plant. Total number of flower heads per plant and florets per plant were positively correlated with each other and with the root crown diameter. Root crown diameter is, therefore, a good indicator of potential fecundity in meadow salsify. Greater seed production by larger plants may compensate, at least in part, for the high juvenile mortality and longer generation time in this species. The results suggest that prolific seed production and long vegetative survival are important strategies in the maintenance of meadow salsify populations.

scholarly journals Treatment and Prognosis of Postoperative Acute Cerebral Venous Infarctions

2021 ◽  
Author(s):  
Qing Cai ◽  
Shoujie Wang ◽  
Jiahua Zhou ◽  
Huaizhou Qin ◽  
Dayun Feng
Keyword(s):  
Hemifacial Spasm ◽  
Lateral Ventricle ◽  
Surgical Intervention ◽  
Parietal Lobe ◽  
Neurological Dysfunction ◽  
Cerebral Vein ◽  
Cortical Vein ◽  
Vegetative Survival ◽  
Intracranial Lesions ◽  
Ct And Mri

Abstract IntroductionThe incidence of cerebral venous infarctions is not high, but this condition can cause serious complications. This paper summarizes the cases of serious complications after cerebral venous infarctions and proposes corresponding treatment strategies.MethodsA retrospective analysis was performed on 5 patients that had severe complications secondary to injury or sacrifice of related veins during the resection of different intracranial lesions (cerebellopontine angle, lateral ventricle, frontal lobe, falx parietal lobe, frontal parietal lobe). There were 2 males and 3 females, aged 34-58 years. Routine CT and MRI/MRV examinations were performed before the operation, and the diagnoses were a hemifacial spasm, a meningioma of the lateral ventricle, a hemangioma, a falx meningioma and a glioma. Postoperative CT examinations were performed to understand the intracranial conditions of the patients.ResultsFive cases had injuries to associated veins, which included the cerebellar cortical vein, internal cerebral vein, middle frontal vein, straight sinus, and postfrontal vein, during the operations. There were 2 cases of venous infarctions, 3 cases of hemorrhagic infarctions, 2 cases who had conservative treatment, 3 cases who had surgical treatment, 1 case who died (the hemifacial spasm), 1 case who had a vegetative survival (the lateral ventricular meningioma), and 3 cases with good recoveries (the hemangioma, falx meningioma, and glioma).ConclusionsSurgeons should pay more attention to intracranial vein injuries during procedures. Acute neurological dysfunction or even death may occur after these injuries. Surgeons should closely monitor the condition of the patient and proceed with surgical intervention if necessary. The prognosis is usually good for these surgery cases, but the prognosis can be poor if important veins are injured. The key to avoiding cerebral venous infarctions is to preserve the integrity of the veins to the greatest extent during the operation.

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