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Autumn Months (autumn + month)
Selected AbstractsComparison of the life history strategies of three Dysdercus true bugs (Heteroptera: Pyrrhocoridae), with special reference to their seasonal host plant useENTOMOLOGICAL SCIENCE, Issue 4 2005Katsuyuki KOHNO Abstract The life history strategy and seasonal host plant use of three Dysdercus bugs (D. cingulatus, D. poecilus and D. decussatus) were compared based on 2 years of twice monthly observations on Ishigaki-jima Island (24°N, 124°E) in the southernmost part of Japan. Dysdercus poecilus reproduced almost year round, exclusively on Sida rhombifolia, which bears fruit and/or seeds almost year round. Dysdercus cingulatus reproduced successively on various malvaceous and bombacaceous plant species, according to their seasonal fruiting cycles. Its robust reproduction was observed on Hibiscus makinoi during winter months and on Chorisia speciosa and Bombax ceiba in early summer, whereas small-scale reproduction was observed on various malvaceous plant species during the summer and autumn months. Dysdercus decussatus reproduced on Hibiscus tiliaceus and Thespesia populnea during the summer months, when these host plants bear abundant fruit and/or seeds, and its adults formed conspicuous aggregations without copulation on the underside of the leaves of those plants from November to the subsequent May. Each Dysdercus species showed a species-specific life history strategy according to the differences in the phenology of their host plants. [source] A new morphospecies of Microcystis sp. forming bloom in the Cheffia dam (Algeria): Seasonal variation of microcystin concentrations in raw water and their removal in a full-scale treatment plantENVIRONMENTAL TOXICOLOGY, Issue 4 2007Hichèm Nasri Abstract Toxic cyanobacterial blooms are an increasing problem in Algeria. The production of cyanotoxins (microcystins) and their presence in drinking water represent growing hazards to human health. In this study, seasonal variations in the concentrations of total microcystins and physicochemical parameters (pH, temperature, dissolved oxygen, nitrate, orthophosphate, and chlorophyll- a) were analyzed in the Cheffia dam (Algeria), mainly used to supply drinking water. The removal of cyanobacterial cells and microcystins was also evaluated in full-scale plant associated with the Cheffia reservoir. The levels of microcystins (MCYSTs) in both raw and drinking water were evaluated using the protein phosphatase type 2A (PP2A) inhibition test as MCYST-LR equivalents. Identification of microcystin variants was achieved by LC/MS/MS. During the period of study (March,December 2004), microscopic observation showed the dominance in the autumn months (September,November) of a new morphospecies of Microcystis sp. The MCYST-LR equivalent concentrations in raw water varied between 50.8 and 28,886 ng L,1. The highest level of toxins was observed in October 2004 and was significantly correlated with the chlorophyll- a. Three variants of microcystins assigned as microcystin-YR (MCYST-YR), microcystin-LR (MCYST-LR), and 6Z -Adda stereoisomer of MCYST-LR were observed in the crude extract of the Microcystis sp. bloom sample. During the bloom period, total elimination of Microcystis sp. and toxins were achieved through a classical treatment plant comprised of coagulation and flocculation, powdered activated carbon at 15 mg L,1, slow sand filtration and chlorination before storage. © 2007 Wiley Periodicals, Inc. Environ Toxicol 22: 347,356, 2007. [source] Survival of sea-water-adapted trout, Salmo trutta L. ranched in a Danish fjordFISHERIES MANAGEMENT & ECOLOGY, Issue 4 2000S. S. Pedersen The effect of seawater adaptation on the survival of coastally released post-smolt trout, Salmo trutta L., was investigated by release: (1) directly (with no adaptation); (2) after retention in net pens in the sea for 29,131 days (delayed release); (3) after feeding with a high-salt diet (12,13.5% NaCl) for 4 weeks; and (4) after a combination of (2) and (3). In total, 17 640 trout (age = 1+, 1.5 and 2+ years; mean fork lengths = 18.2,25.6 cm) were released in 14 batches in the summer or autumn months of 1986,1989. All fish were of domesticated origin and Carlin tagged. Survival and instantaneous mortality rates (total and fishing mortality) were estimated from reported recaptures. Mortality rates were estimated for: (1) the post-smolt period; (2) the period until the legal size of capture (40 cm) was attained; and (3) for larger sea-trout. Release with a delay of 4 weeks gave an increased survival rate. A longer adaptation period did not increase survival. On average, survival was increased by 36%. Survival was not increased by high-salt diets. Until attainment of the legal size for capture, survival was 9.6% higher on average, with extremes as low as 1.7% and as high as 38% in individual batches. [source] Patterns of reproduction in two sympatric gerbil species in arid EgyptINTEGRATIVE ZOOLOGY (ELECTRONIC), Issue 2 2009Sohail SOLIMAN Abstract Despite a significant number of studies on the reproductive characteristics of small mammals, very little of this work has been conducted on species in Egpyt. Here, the Egyptian greater gerbil (Gerbillus pyramidum Saint-Hilaire, 1825) and Anderson's lesser Egyptian gerbil (Gerbillus andersoni De Winton, 1902) in northeastern Egypt were surveyed. Breeding behavior in these species was synchronized with rainfall in the winter and spring months. Surprisingly however, the removal of individual gerbils throughout the course of study resulted in an extension of reproductive activity into the dry summer and autumn months in the latter part of the sampling. These results are discussed in the context of density-dependent reproductive behavior in small mammals. [source] Autochthonous hepatitis E in southwest EnglandJOURNAL OF VIRAL HEPATITIS, Issue 5 2007H. R. Dalton Summary., Although autochthonous hepatitis E has been reported in developed countries, its extent and nature in the United Kingdom are unclear. The aim of the present study was to report the natural history, lifestyle risk factors and molecular epidemiology of autochthonous hepatitis E infection in southwest England. Three hundred and thirty-three patients with unexplained hepatitis were tested for markers of hepatitis E virus (HEV) infection over a 7-year period. HEV RNA isolated from the cases was amplified and characterized. Of the 333 patients, 21 had autochthonous hepatitis E. Patients were middle-aged or elderly and males were more commonly affected. Clinical manifestations ranged from asymptomatic infection to severe hepatitis. Of the 21 patients, 20 recovered within 6 weeks. None of the cases had travelled to an area endemic for HEV. None of the patients were vegetarian and all ate pork. Of the 21 cases, 20 occurred in the spring, summer and autumn months. All polymerase-chain-reaction-confirmed cases carried HEV genotype 3, which bore close sequence homology to HEV circulating in UK pigs. In the United Kingdom, autochthonous hepatitis E may be more common than previously recognized. Although the mode of transmission remains to be determined, it may be a zoonosis with pigs as a reservoir. Hepatitis E should be considered a public health issue in the United Kingdom. [source] Reproductive seasonality in the Tete veld rat (Aethomys ineptus) (Rodentia: Muridae) from southern AfricaJOURNAL OF ZOOLOGY, Issue 2 2006S. P. Muteka Abstract Very little is known about the reproductive biology of the recently recognized Tete veld rat Aethomys ineptus. In the present study, we investigated the seasonality of reproduction in this newly recognized rodent using a number of histological and endocrinological parameters. Body mass, reproductive tract morphometrics, gonadal histology, and plasma testosterone concentrations in males and plasma oestradiol-17, and progesterone concentrations in females were assessed from a population in the north-central part of South Africa over a 12-month period in order to ascertain the pattern of reproduction in the species. Seminiferous tubule diameters in 59 males were significantly larger between September and February relative to between March and August. Although spermatogenesis was prevalent in the southern hemisphere winter (June,August), the number of spermatozoa in the epididymides decreased in the southern hemisphere spring (September,November), summer (December,February) and autumn (March,May). Testicular mass relative to body mass and testicular volume regressed between May and September but exhibited recrudescence between September and April, whereas plasma testosterone concentrations increased significantly between September and February relative to between March and August. Ovarian histology of 67 females showed corpora lutea to be present throughout the year, but decreased in number during winter, whereas mean plasma progesterone concentration increased significantly between August and November and again between February and April. This bimodal pattern of progesterone concentration suggests that up to two litters per breeding season may be raised by the Tete veld rat. Gravid females were found between October and April, whereas gravid or lactating females were conspicuously absent between May and September. Collation of all these data suggests that the Tete veld rat is a seasonal breeder with reproduction confined predominantly to summer and autumn months of the southern hemisphere. However, the presence of follicular development in females and the presence of corpora lutea outside the breeding season imply that the Tete veld rat may undergo spontaneous ovulation. [source] COST, DEMOGRAPHICS AND INJURY PROFILE OF ADULT PEDESTRIAN TRAUMA IN INNER SYDNEYANZ JOURNAL OF SURGERY, Issue 1-2 2006Timothy J. Small Background: Pedestrian accidents are associated with substantial morbidity, mortality and cost; however, there has been very little published work on this topic in Australasia over recent years. The objective of this study was to examine the demographics, injury profile, outcomes and cost of pedestrian versus motor vehicle accidents in a central city hospital in Sydney. Methods: Consecutive pedestrians injured by motor vehicles and admitted as inpatients during the years 2002,2004 were identified from our prospective trauma registry. A retrospective review included patient profiles (age, sex, time of injury and blood alcohol), injury pattern, cost, morbidity and mortality. Results: A total of 180 patients (64% men and 36% women) with a mean age of 46 and mean injury severity score of 14.1 were identified. Two peak injury periods were observed: one between 17.00 and 18.00 hours (P < 0.01) and the other between 20.00 and 22.00 hours (P < 0.01). Significantly more injuries occurred on Friday (P < 0.01) and during autumn months (P < 0.05). Musculoskeletal (34.3%), head (31.8%) and external (20.2%) injuries predominated. Forty-nine per cent of patients tested positive for consuming alcohol, with an average blood alcohol concentration (BAC) of 0.22%. Alcohol consumption was associated with a worse outcome in terms of hospital and intensive care unit stay, morbidity and mortality. The average length of stay was 13.4 days costing $A16320 per admission. Sixteen patients died (mortality rate of 8.9%), with the highest rate in the elderly group (22.7%) (P < 0.001). Conclusions: Pedestrian accidents in inner Sydney are common with injuries predominating in intoxicated adult males. Mortality was higher in the elderly group. Injuries to the head and lower extremities predominate. Hospital stays are lengthy, resulting in a high cost for each admission. [source] | ||||||||||||||||