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Period February (period + february)
Selected AbstractsPatterns in the spawning of cod (Gadus morhua L.), sole (Solea solea L.) and plaice (Pleuronectes platessa L.) in the Irish Sea as determined by generalized additive modellingFISHERIES OCEANOGRAPHY, Issue 1 2000Eleven ichthyoplankton cruises were undertaken covering most of the Irish Sea during the period February to June, 1995. To identify spawning localities and investigate temporal trends in egg production, the data on stage 1 A egg distributions of cod (Gadus morhua), plaice (Pleuronectes platessa) and sole (Solea solea) have been modelled using generalized additive models (GAMs). A two-stage approach was adopted where presence/absence was firstly modelled as a binary process and a GAM surface subsequently fitted to egg production (conditional on presence). We demonstrate that this approach can be used to model egg production both in space and in time. The spawning sites for cod, plaice and sole in the Irish Sea were defined in terms of the probability of egg occurrence. For cod, we demonstrate that by integrating under predicted egg production surfaces, a cumulative production curve can be generated and used to define percentiles of production and thus delimit the extent of the spawning season. However, for plaice and sole, the surveys did not fully cover the spawning season and the limitations that this imposes on GAM modelling of these data are discussed. Comparison of the spawning sites in 1995 with historical data suggests that the locations of cod, plaice and sole egg production in the Irish Sea have probably remained relatively constant over the last 30 years. [source] Hourly and daily clearness index and diffuse fraction at a tropical station, Ile-Ife, NigeriaINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 8 2009E. C. Okogbue Abstract Dataset consisting of hourly global and diffuse solar radiation measured over the period February 1992 and December 2002 have been utilized to investigate the diurnal and seasonal variations of hourly and daily clearness index together with the diffuse fraction at a tropical station Ile-Ife (7.5°N, 4.57°E), Nigeria. Statistical analysis (the frequency and cumulative frequency distribution of the hourly and daily clearness index) and subsequent characterization of the sky conditions over the station based on these were also done, and their implications for solar energy utilization in the area discussed. Daytime (11:00,15:00 LST) monthly mean hourly diffuse fraction, M,d (explained in a separate ,List of Symbols' provided, along with other symbols used in this article), have values, which are most of the time less than 0.52, 0.54 and 0.60 respectively for January, February and March in the dry season. However, during the months of July and August (which are typical of the wet season), the values range between 0.61 and 0.85 (being generally greater than 0.65) with the corresponding values of the monthly mean hourly clearness index, M,T, ranging between 0.23 and 0.45. Statistical analysis of hourly and daily clearness index showed that the local sky conditions at the station were almost devoid of clear skies and overcast skies (clear skies and overcast skies occurred for only about 3.5% and 4.8% of the time respectively). The sky conditions were rather predominantly cloudy (cloudy skies occurred for about 88% of the time) all the year round. Copyright © 2009 Royal Meteorological Society [source] Mass balance of a slope glacier on Kilimanjaro and its sensitivity to climateINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 7 2008Thomas Mölg Abstract Meteorological and glaciological measurements obtained at 5873 m a.s.l. on Kersten Glacier, a slope glacier on the southern flanks of Kilimanjaro, are used to run a physically-based mass balance model for the period February 2005 to January 2006. This shows that net shortwave radiation is the most variable energy flux at the glacier-atmosphere interface, governed by surface albedo. The majority of the mass loss (,65%) is due to sublimation (direct conversion of snow/ice to water vapour), with melting of secondary importance. Sensitivity experiments reveal that glacier mass balance is 2,4 times more sensitive to a 20% precipitation change than to a 1 °C air temperature change. These figures also hold when the model is run with input data representative of a longer term (1979,2004) mean period. Results suggest that a regional-scale moisture projection for the 21st century is crucial to a physically-based prediction of glacier retention on Africa's highest mountain. Copyright © 2007 Royal Meteorological Society [source] Ovary development in Greenland halibut Reinhardtius hippoglossoides in west Greenland watersJOURNAL OF FISH BIOLOGY, Issue 5 2005C. S. Simonsen Maturity in adult female Greenland halibut Reinhardtius hippoglossoides was studied in three areas in west Greenland waters: the inshore area in Disko Bay and two offshore areas, Baffin Bay and Davis Strait. The aim was to monitor maturity changes in the inshore fjords of Disko Bay over an extended period from winter to autumn and compare these findings with specimens from Baffin Bay and the presumed spawning area in Davis Strait. A significant difference in maturity level was observed in and between the three areas. In Disko Bay maturity indices increased significantly in August and September both with respect to the gonado-somatic index (IG) and the size in the leading oocyte cohort. In the period February to May no significant changes were observed. Mature ovaries were only observed among fish >80 cm total length and only among a fraction of these large fish. Offshore areas of Baffin Bay, even though poorly sampled, showed similar signs in the maturity indices as in Disko Bay. Relative to Disko Bay and Baffin Bay, female fish in Davis Strait had more progressed maturity indices. Furthermore, almost all fish in Davis Strait showed signs of progressed maturity contrary to Disko and Baffin Bay. A large proportion of the Greenland halibut in Disko and Baffin Bay apparently did not begin the maturation cycle until very late in their life history or were repeat spawners with a multi-year maturation cycle. These observations could thus support the hypothesis that Greenland halibut have a prolonged adolescent phase. Atresia was highest in the early phases of maturation in Greenland halibut but relatively high levels of atresia were also observed in fish in more advanced maturity phase. The first was ascribed to fecundity regulation while the latter could be linked to the fish's fitness condition but it was not possible to show this with the available condition index. [source] Quality of farmed Atlantic cod: effects of season and storageAQUACULTURE RESEARCH, Issue 8 2010Hilde Herland Abstract Farming of Atlantic cod makes it possible to supply cod throughout the year. The aim of this study was to investigate the effects of season and postmortem ice storage on the quality parameters of farmed cod. Farmed Atlantic cod were sampled from the same pen in the period February 2006,March 2007. Cod whole body and somatic weight, condition factors and hepatosomatic index were all affected by season, all decreasing during maturation and spawning in the winter. Muscle pH and water were influenced by season, increasing during maturation and spawning and then decreasing after spawning. Season also affected the colour of the fillet. There was a significant increase in whiteness post-spawning and a decrease during the second maturation. Water-holding capacity (WHC), levels of trimethylamine oxide and trimethylamine, as well as microbiological data, did not vary due to season. Muscle pH, water content, WHC and microbial counts increased during storage for all samplings. [source] Factors associated with return-to-work and health outcomes among survivors of road crashes in VictoriaAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 2 2010Michael Fitzharris Abstract Objective: To explore the relationships between injury, disability, work role and return-to-work outcomes following admission to hospital as a consequence of injury sustained in a road crash. Design and setting: Prospective cohort study of patients admitted to an adult trauma centre and two metropolitan teaching hospitals in Victoria, Australia. Participants were interviewed in hospital, 2.5 and eight months post-discharge. Participants: Participants were 60 employed and healthy adults aged 18 to 59 years admitted to hospital in the period February 2004 to March 2005. Results: Despite differences in health between the lower extremity fracture and non-fracture groups eight months post-crash the proportions having returned to work was approximately 90%. Of those returning to work, 44% did so in a different role. After adjustment for baseline parameters, lower extremity injuries were associated with a slower rate of return to work (HR: 0.31; 95%CI: 0.16,0.58) as was holding a manual occupation (HR: 0.16; 95%CI: 0.09,0.57). There were marked differences in physical health between and within the injury groups at both follow-up periods. Conclusions: These results demonstrate that both injury type and severity and the nature of ones occupation have a considerable influence on the rate and pattern of return to work following injury. Further, persisting disability has a direct influence on the likelihood of returning to work. The implications of these findings and the types of data required to measure outcome post-injury are discussed. [source] The influence of the full moon on the number of accessions to an animal emergency centreAUSTRALIAN VETERINARY JOURNAL, Issue 10 2007TJ McALEES Objective To test the hypothesis that the number of animal emergency centre accessions is associated with the time of the full moon. Design and procedure Retrospective study. A comparison was made of the number of accessions to the University of Melbourne Animal Emergency Centre in the period February 2003 to January 2006 on full moon and non,full moon days, adjusted for day of the week and public holiday. A three day period with the day of the full moon as the middle day was taken to be a full moon period. Results A total of 12,102 animals were presented to the Centre in this time. An adjusted count ratio of 1.048 (95% CI 0.97 to 1.14; P = 0.26) for accessions on full moon days compared with those on non,full moon days indicated that there was no significant association between the full moon and the number of accessions per day. Conclusion There was no significant difference between the number of animals presented to the University of Melbourne Animal Emergency Centre on full moon days and non,full moon days. [source] | |||||||||||||