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Whole Year (whole + year)
Selected AbstractsAnnual cycle of clupeiform larvae around Gran Canaria Island, Canary IslandsFISHERIES OCEANOGRAPHY, Issue 4 2006P. BÉCOGNÉE Abstract The distribution and abundance of fish larvae was studied along the eastern and southern shelf of Gran Canaria Island (Canary Islands) from July 2000 to June 2001. Oblique bongo hauls were carried out fortnightly during the daytime, coinciding with days of full and new moon. During February, the area was sampled every 2,5 days. About 17.3% of the ichthyoplanktonic community was composed of clupeiform larvae: 92.9% of these larvae were Sardinella aurita, whereas 4.7% and 2.4% were respectively Engraulis encrasicolus and Sardina pilchardus. Sardinella aurita larvae appeared during the whole year with two periods of maximum abundance: June to September and December to February. During the full moon their abundance was on average 38.5% (±6.8%) of their numbers during the new moon, showing a clear lunar periodicity. Engraulis encrasicolus larvae appeared from November to March, also coinciding with the new moon. Sardina pilchardus larvae only appeared during two short periods, both coinciding with filaments shed from the African coastal upwelling which reached the island. This fact confirms the transport of fish larvae from the upwelling area off northwest Africa to the Canary Islands, promoting a genetic flow among both sites. [source] Nitrogen-regulated effects of free-air CO2 enrichment on methane emissions from paddy rice fieldsGLOBAL CHANGE BIOLOGY, Issue 9 2006XUNHUA ZHENG Abstract Using the free-air CO2 enrichment (FACE) techniques, we carried out a 3-year mono-factorial experiment in temperate paddy rice fields of Japan (1998,2000) and a 3-year multifactorial experiment in subtropical paddy rice fields in the Yangtze River delta in China (2001,2003), to investigate the methane (CH4) emissions in response to an elevated atmospheric CO2 concentration (200±40 mmol mol,1 higher than that in the ambient atmosphere). No significant effect of the elevated CO2 upon seasonal accumulative CH4 emissions was observed in the first rice season, but significant stimulatory effects (CH4 increase ranging from 38% to 188%, with a mean of 88%) were observed in the second and third rice seasons in the fields with or without organic matter addition. The stimulatory effects of the elevated CO2 upon seasonal accumulative CH4 emissions were negatively correlated with the addition rates of decomposable organic carbon (P<0.05), but positively with the rates of nitrogen fertilizers applied in either the current rice season (P<0.05) or the whole year (P<0.01). Six mechanisms were proposed to explain collectively the observations. Soil nitrogen availability was identified as an important regulator. The effect of soil nitrogen availability on the observed relation between elevated CO2 and CH4 emission can be explained by (a) modifying the C/N ratio of the plant residues formed in the previous growing season(s); (b) changing the inhibitory effect of high C/N ratio on plant residue decomposition in the current growing season; and (c) altering the stimulatory effects of CO2 enrichment upon plant growth, as well as nitrogen uptake in the current growing season. This study implies that the concurrent enrichment of reactive nitrogen in the global ecosystems may accelerate the increase of atmospheric methane by initiating a stimulatory effect of the ongoing dramatic atmospheric CO2 enrichment upon methane emissions from nitrogen-poor paddy rice ecosystems and further amplifying the existing stimulatory effect in nitrogen-rich paddy rice ecosystems. [source] Circulation dynamics of Mediterranean precipitation variability 1948,98INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 15 2003A. Dünkeloh Abstract Canonical correlation analysis is used to identify main coupled circulation,rainfall patterns and to relate recent variability and trends of Mediterranean precipitation to large-scale circulation dynamics. Analyses are based on geopotential heights (500 and 1000 hPa levels) for the North Atlantic,European area (National Centers for Environmental Prediction,National Center for Atmospheric Research reanalysis) and on highly resolved (0.5° × 0.5° ) monthly rainfall grids (Climatic Research Unit, Norwich) selected for the Mediterranean area during the 1948,98 period. Combining monthly analyses with similar characteristics to seasonal samples yields winter (October,March), spring (April,May) and summer (June,September) types of coupled variability; a particular autumn type for the whole Mediterranean does not occur on the monthly time scale. Coupled patterns specifically linked to one or two seasons include an east Atlantic jet (EA-Jet) related pattern for summer and a Mediterranean meridional circulation (MMC) pattern for winter and spring. The most important pattern recurring with dynamical adjustments throughout the whole year reflects the seasonal cycle of the Mediterranean oscillation (MO), which is linked (with seasonal dependence) to the Northern Hemisphere teleconnection modes of the Arctic oscillation (AO) and North Atlantic oscillation (NAO). Winter rainfall trends of the recent decades marked by widespread decreases in the Mediterranean area and by opposite conditions in the southeastern part are linked to particular changes over time in several of the associated circulation patterns. Thus, different regional rainfall changes are integrated into an overall interrelation between Mediterranean rainfall patterns and large-scale atmospheric circulation dynamics. Copyright © 2003 Royal Meteorological Society [source] Short-scale diversity in a dynamic rain fade environmentINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 2 2005Cristina Enjamio Abstract This article is concerned with using time-varying uniformly spaced rainfall data to investigate the concept and values of instantaneous diversity gain. This has been obtained on a minute-by-minute basis in order to illustrate the behaviour of a VSAT communication system which switches to the most reliable link every minute. The simulations have been carried out using a whole year of rain data obtained from the recordings of a dense rain gauge network located in Barcelona. After illustrating the concept of instantaneous diversity gain, this paper shows the results obtained for various site separations and 20 GHz. These results have been plotted together with the values given by some long-term-based models. The comparison shows that such models are not appropriate for dynamic site diversity. This was found to increase the reliability of a VSAT system, especially under severe rain conditions in which the rainfall rates are spatially arranged in rain cells and the attenuation experienced by the two sites is strongly decorrelated. The correlation coefficient between the attenuation series calculated for several separation distances has also been obtained to illustrate this concept. Finally, the paper gives the attenuation distributions calculated for a VSAT system with and without site diversity and for several site separations. Copyright © 2005 John Wiley & Sons, Ltd. [source] Body mass change strategies in blackbirds Turdus merula: the starvation,predation risk trade-offJOURNAL OF ANIMAL ECOLOGY, Issue 2 2005R. MACLEOD Summary 1It is theoretically well established that body mass in birds is the consequence of a trade-off between starvation risk and predation risk. There are, however, no studies of mass variation from sufficiently large wild populations to model in detail the range of diurnal and seasonal mass change patterns in natural populations and how these are linked to the complex environmental and biological variables that may affect the trade-off. 2This study used data on 17 000 individual blackbirds Turdus merula to model how mass changes diurnally and seasonally over the whole year and over a wide geographical area. Mass change was modelled in respect of temperature, rainfall, day length, geographical location, time of day and time of year and the results show how these mass changes vary with individual size, age and sex. 3The hypothesis that seasonal mass is optimized over the year and changes in line with predictors of foraging uncertainty was tested. As theory predicts, reduced day length and reduced temperature result in increased mass and the expected seasonal peak of mass in midwinter. 4The hypothesis that diurnal mass gain is optimized in terms of starvation,predation risk trade-off theory was also tested. The results provide the first empirical evidence for intraspecies seasonal changes in diurnal mass gain patterns. These changes are consistent with shifts in the relative importance of starvation risk and predation risk and with the theory of mass-dependent predation risk. 5In winter most mass was gained in the morning, consistent with reducing starvation risk. In contrast, during the August,November non-breeding period a bimodal pattern of mass gain, with increases just after dawn and before dusk, was adopted and the majority of mass gain occurred at the end of the day consistent with reducing mass-dependent predation risk. The bimodal diurnal mass gain pattern described here is the first evidence that bird species in the wild gain mass in this theoretically predicted pattern. [source] Environmental niche of the smut lizard population on a sandy coastal ecosystem of Southeastern Tenerife (Canary Islands)MARINE ECOLOGY, Issue 2008Antonio De Los Santos Abstract Relationships among environmental patterns and population size of the smut lizard Gallotia galloti galloti Oudart, 1839 (Sauria Lacertidae) were examined in the context of longer time-scale variability on a sandy beach and adjacent environments of Southeastern Tenerife. Seasonal and yearly patterns in the population size were likewise analyzed in relation to climatic and anthropic variables. Six sampling plots (coastal, sweet tabaiba, tuff, lava, sandy lava and crater) were selected following a perpendicular transect to the sandy fringe that extends from the beach toward the volcanic interior. Pitfall trapping was conducted from 1984 to 2005, and capture,mark,recapture technique and the Jolly,Seber method were used to estimate population sizes. The highest population size estimates were shown on the sandy lava plot and the neighboring lava plot, reaching values of about 3500 individuals ha,1 during the spring. The population was active almost the whole year, with seasonal patterns of activity from March to October. Seasonal temperature and population size patterns were correlated but the ,calima' episodes produced some disturbance. Gallotia galloti galloti was one of the most abundant lizards of all the species studied and its population size has not remained stable over the study period, probably because of the absence of predation and competition, and because of human interference and environmental instability. [source] Synoptic features associated with critical water level rises in the Río de la PlataMETEOROLOGICAL APPLICATIONS, Issue 2 2005A. P. Alessandro This study aims to describe the synoptic features that caused the water level in the Río de la Plata estuary to rise above critical levels between December 1989 and December 1998. Floods in the estuary can seriously affect the land beside the river from Punta Indio (35.22°S,57.17°W) to the Paraná delta, including the lowlands of Buenos Aires City. Surface pressure patterns associated with floods in the Río de la Plata estuary were obtained by using Quartimax rotated T-mode Principal Component Analysis (PCA) of 1000 hPa geopotential heights. The PCA patterns and 1000 hPa composite and anomaly fields show two main causes for overflows in the Río de la Plata estuary. First, the presence of a surface anticyclone, located south of Buenos Aires province and over northern Patagonia; and, second, cyclogenesis over northeastern Argentina or over Uruguay. The two synoptic features are often present simultaneously. Two representative points were selected in the area under study: one over the continent at the Aeroparque meteorological station (34.34°S,58.25°W) and another over the ocean between 36°S,56°W and 36°S,50°W. Predominant 1000 hPa wind directions associated with overflows were SE at the former location and SSW at the latter. Based on the analysis of the obtained fields, the relationship between the estuary overflow and blocking situations and/or positive pressure anomalies over southern South America and adjacent seas was studied. The zonal circulation index (I), used to detect blocking actions, was found to be useful for identifying synoptic situations related to the estuary swelling. The probability of water level rises in the Río de la Plata with a blocking or I > 0 at 70°W is 0.48, 0.72, 0.78 and 0.73, for summer, autumn, winter and spring, respectively. When I > 0 is observed over the Atlantic at 40°W the probability of flooding is 0.16 for the whole year, but it decreases to 0.028 in autumn, winter and spring. These results and weather charts from different numerical prediction models show that alerts of possible Río de la Plata estuary overflow can be released five days in advance. Copyright © 2005 Royal Meteorological Society [source] Spinal Cord Stimulation for Chronic Visceral Abdominal PainPAIN MEDICINE, Issue 3 2010Leonardo Kapural MD Abstract Background., Spinal cord stimulation (SCS) may reduce pain scores and improve function in patients with chronic visceral abdominal pain. We thus present our large clinical experience in SCS for visceral abdominal pain. Methods., We trialed spinal cord stimulation in 35 patients, each of whom was shown by retrograde differential epidural block to have either visceral pain (n = 32) or mixed visceral and central pain (n = 3). SCS trials lasted 4 to 14 days (median 9 days). SCS lead tips were mostly positioned at T5 (n = 11) or T6 (n = 10). Results., Thirty patients (86%) reported at least 50% pain relief upon completion of the trial. Among these, pretrial visual analog scale (VAS) pain scores averaged 8.2 ± 1.6 (SD) and opioid use averaged 110 ± 119 mg morphine sulfate equivalents. During the trial, VAS pain scores decreased to 3.1 ± 1.6 cm (P < 0.001, Mann,Whitney Rank Sum Test) and opioid use decreased to 70 ± 68 mg morphine equivalent a day (P = 0.212). Five patients failed the trial, one was lost to follow-up, and 19 were followed for the whole year. Seven patients were either followed for less than a year (n = 3) or the SCS system was removed due to infection or lead migration (n = 4). One patient despite the successful trial felt no improvements at 6 months after the implant and requested an explant of the SCS device. Among the 28 patients who received permanent implant, 19 were followed at least a year. Their VAS pain scores remained low (3.8 ± 1.9 cm; P < 0.001) at 1 year, as did opioid use (38 ± 48 mg morphine equivalents; P = 0.089). Conclusions., Spinal cord stimulation may be a useful therapeutic option for patients with severe visceral pain. [source] Farm work exposure of older male farmers in Saskatchewan,AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 7 2010Donald C. Voaklander PhD Abstract Background The average age of farmers in North America is increasing each year. Research has determined that age and health status are both related to increased risk of injury. The purpose of this research was to determine the association of health and medication factors with exposure to farm work in older male farmers. Methods As part of a cohort study to study determinants of injury on Saskatchewan farms, 5,502 farm people associated with 2,386 Saskatchewan farms were surveyed by mail questionnaire during the winter of 2007. The primary dependent variable was average hours per week of farm work. Independent variables included illnesses, age, and medication use. Results The mean number of hours worked per week by farmers aged 55 years and older was 48. There was a significant relationship between age and hours worked with each year of age accounting for about 0.85,hr less work per week. Medication use was related to a reduction in weekly work hours during the busy fall season but was not related to work exposure averaged over the whole year. In multivariable linear regression analysis, the main contributing variables to farm work exposure were: retired status (,), working off farm (,), and age (,). Conclusion The amount of hours older farmers work on the farm is considerable compared to any other occupational category. While there is a declining trend in the amount of work, a 75-year-old farmer still works, on average, about 34,hr per week. Some farmers do appear to self-limit during busy times of the year if they are taking medication. Am. J. Ind. Med. 53:706,715, 2010. © 2010 Wiley-Liss, Inc. [source] Investigation to estimate the short circuit current by applying the solar spectrumPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 3 2008Jun Tsutsui Abstract The influence of the solar spectrum is investigated to estimate the outdoor short circuit current (Isc) of various photovoltaic (PV) modules. It is well known that the solar spectrum always changes. Hence, it is rare to fit the standard solar spectrum AM1·5G defined in standard IEC 60904-3. In addition, the spectral response (SR) of PV module is different depending on the material. For example, crystal silicon (c-Si) has broad sensitivity that the wavelength range is between 350 and 1150,nm; meanwhile, amorphous silicon (a-Si) has relatively narrow sensitivity comparing to c-Si. Since Isc of the PV module decides by multiplying the solar spectrum and SR together, it is necessary to investigate the solar spectrum to estimate the outdoor Isc in addition to the solar irradiance and module temperature. In this study, the spectral mismatch is calculated and the outdoor Isc is estimated in the whole year. Copyright © 2007 John Wiley & Sons, Ltd. [source] Experimental solar spectral irradiance until 2500,nm: results and influence on the PV conversion of different materialsPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 4 2007J. J. Pérez-López Abstract In this work, results are presented concerning solar spectral irradiance measurements performed in Madrid in the wavelength range 250,2500,nm, that is, extending the spectral range far away from the wavelengths where PV semiconductors are active. These data were obtained considering a horizontal receiver surface during selected clear days covering the four seasons of the year. PV materials having different spectral responses (m-Si, a-Si, CIGS, CdTe) have been considered to calculate spectral factors (SF) taking as reference the standard solar spectrum AM1.5 defined in standard IEC 60904-3. From these SFs, the influence of natural solar spectral variations in PV conversion has been established. It is shown, for example, that PV technologies based on a-Si are highly favored, from the spectral point of view, in spring,summer compared to other technologies having broader spectral responses, which are more favored in autumn,winter. From the experimental measured solar spectra, we have calculated Weighed Solar Spectra (WSS) corresponding to the four seasons of the year and also to the whole year. The WSS represents, for a certain period of time, the solar spectrum weighed over the irradiance level. SFs have been calculated for different WSSs showing spectral gains for the four PV materials during almost the full year. Otherwise, it is also shown in this work how the near-IR part of the solar spectrum affects the evaluation of the solar resource as a whole when reference solar cells made of different PV materials are used. For typical m-Si, a-Si, CIGS, and CdTe solar cells, the ratio of Isc over global irradiance is not constant along a given day showing variations that depend on the season and on the PV material considered. © 2006 John Wiley & Sons, Ltd. [source] What Really Happened to Child Poverty in the UK under Labour's First Term?*THE ECONOMIC JOURNAL, Issue 488 2003Mike Brewer Child poverty in Britain fell in Labour's first term, though by much less than micro-simulation exercises suggested. Nonetheless, the decline is statistically significant, and is greater if measured just in the last 6 months of 2000/1, rather than the whole year. The decline also proves robust to the choice of poverty line, although that which the Government has emphasised (60% of contemporary income) shows a somewhat bigger drop than any other than any other poverty line that is a fraction of median income. Among those who remain poor, the average shortfall in measured income below the poverty line has increased since 1996/7. Looking ahead, the methodology currently used in official poverty statistics may limit the potential to reduce child poverty significantly further. [source] Solving the controversy about the astronomical significance of the rock formation "Teufelstein" in StyriaASTRONOMISCHE NACHRICHTEN, Issue 6 2009S. Rothwangl Abstract As two very controversial surveys of the rock formation "Teufelstein" exist in literature (H. Haupt versus H.M. Maitzen as well as W. Schlosser), a photographic documentation of solar and lunar rising and setting points throughout a whole year as well as a remeasurement with a solar compass was carried out on the spot. The result is that the formation is not an accurate solar marker but could only have served as a warning peg for the summer solstice setting point (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Edge Effects and Seedling Bank Depletion: The Role Played by the Early Successional Palm Attalea oleifera (Arecaceae) in the Atlantic ForestBIOTROPICA, Issue 2 2010Antônio Venceslau Aguiar ABSTRACT In this study, we examined the impacts of Attalea oleifera on the structure of seedling bank and discuss potential mechanisms of palm influence. Seed rain, seedling bank, and palm leaf fall were assessed beneath the canopy and in the vicinity of 16 adult palms across the edges of a large fragment (3500 ha) of the Atlantic forest. Moreover, we examined A. oleifera impacts on seed germination and seedling mortality by experimentally submitting seeds and seedlings to prolonged palm-leaf covering. As expected, seedling bank beneath the adults exhibited reduced abundance and species richness at local and habitat scale. Small to large seeds (3.1,30 mm) were underrepresented in the seed rain below adults palms, while experimental leaf covering drastically reduced both seed germination and seedling survivorship. A. oleifera leaf fall occurred over the whole year (3.6±2.7 leaves/individual/yr), which resulted in deep leaf litter mounds (10.7±9.2 cm). Finally, adult palm density (21.6±11.9 individuals/ha) correlated negatively with seedling density across Attalea clusters. Our results suggest that A. oleifera exerts negative effects on the seedling bank by reducing seedling abundance and richness as a consequence of two complementary mechanisms: impoverished and size-biased seed rain plus reduced seed germination and increased seedling mortality due to prolonged covering by fallen leaves. Abstract in Portuguese is available at http://www.blackwell-synergy.com/loi/btp [source] Ultraviolet radiation exposure pattern in winter compared with summer based on time-stamped personal dosimeter readingsBRITISH JOURNAL OF DERMATOLOGY, Issue 1 2006E. Thieden Summary Background, Personal annual ultraviolet (UV) radiation data based on daily records are needed to develop protective strategies. Objectives, To compare UV radiation exposure patterns in the winter half-year (October,March) and the summer half-year (April,September) for Danish indoor workers. Methods, Nineteen indoor workers (age range 17,56 years) wore personal UV dosimeters, measuring time-stamped UV doses continuously during a year. The corresponding sun exposure behaviour was recorded in diaries. Similar data were collected for 28 volunteers during sun holidays in the winter half-year. The relationship between UV dose and sun exposure behaviour was analysed. Results, The ambient UV dose during the winter in Denmark (at 56°N) was 394 standard erythema doses (SED) or 10·5% of the annual ambient UV dose. In winter compared with summer the subjects had: (i) a lower percentage of ambient UV radiation, 0·82% vs. 3·4%; (ii) a lower solar UV dose in Denmark, 3·1 SED (range 0·2,52) vs. 133 SED (range 69,363); (iii) less time outdoors per day with positive dosimeter measurements, 10 min vs. 2 h; and (iv) no exposure (0 SED) per day on 77% vs. 19% of the days. Sun holidays outside Denmark in winter gave a median 4·3 SED per day (range 0·6,7·6) and 26 SED (range 3,71) per trip. Conclusions, In the winter half-year indoor workers received a negligible UV dose from solar exposure in Denmark and needed no UV precautions. No UV precautions are needed from November to February during holidays to latitudes above 45 °N, while precautions are needed the whole year around at lower latitudes. [source] | |||||||||||||||||||