Spring Seasons (spring + season)

Distribution by Scientific Domains

Selected Abstracts

Estimating monthly surface winds for Scania, southern Sweden, using geostrophic wind (1899,1997)

Marie Ekström
Wind direction conditions during the 20th century in Scania, southern Sweden, are investigated using an estimated series of monthly wind vector components (east,west u component and north,south v component). The series is developed from a regression relationship between pairwise (1973 to 1997) monthly averages of 10,m surface wind from Scania and a monthly geostrophic wind, based on mean sea level (MSL) pressure data from the National Center of Atmospheric Research (NCAR). The wind conditions during the 20th century are dominated by winds from southwesterly and westerly directions, particularly during summer and autumn. From the 1980s onwards, increased frequencies of westerly winds are evident in spring and summer; however, similarly large frequencies of westerly winds are also found during the early part of the 20th century. Analysis of the estimated wind series indicates large variation in wind direction during the investigated time period, particularly during 1930 to 1960 when large increases of easterly winds are evident in spring. Increased frequencies of easterly winds were also found in other months during this period but not to the same extent as during the spring season. Thus, the presence of periods with quite different wind characteristics suggests that the overall atmospheric circulation has experienced some shifts in this region during the 20th century. [source]

Effects of Varying Dietary Protein Levels and Feeding Frequencies on Condition and Reproductive Performance of Channel Catfish to Produce Hybrid Catfish

Herbert E. Quintero
The interspecific hybridization of channel catfish, Ictalurus punctatus, females with blue catfish, I. furcatus, males has been identified as a method to further improve production; however, lack of spawning success has affected its commercial application. To facilitate our understanding of the interaction of brood stock nutrition and reproductive performance, we evaluated the interaction of feed quality and feeding frequency. Channel catfish females were classified into two genetic groups, namely, high and low spawning. The treatments were offered during the spring season 70,90 d prior to the start of the spawning season. Induced reproduction was performed using luteinizing hormone releasing hormone analog. Condition of the fish as well as reproductive performance using spawning success, egg production, egg size, and fertilization at 48 h were determined. Changing protein level of the diet from 32 to 42% did not influence spawning, fecundity, or fertilization, but affected egg size and biochemical composition of the eggs. Increasing the feeding frequency from three to six times per week negatively affected spawning in one of the two genetics groups, did not affect egg production and egg fertilization, but had a significant effect on egg size. Older fish performed better than younger fish in terms of spawning success and egg production. [source]

Acute lower respiratory tract infections by human metapneumovirus in children in Southwest China: A 2-year study

Xin Chen MD
Abstract Human metapneumovirus (hMPV) has been reported to cause both upper and lower respiratory tract diseases in susceptible populations, particularly in children and the elderly. In this study, we describe a hospital-based epidemiological study of hMPV in patients presenting to a children's hospital and show the demographic and clinical characteristics associated with hMPV infection in China, retrospectively. Specimens were collected over a 2-year period from children hospitalized with acute lower respiratory tract infections (ALRTI) and analyzed for the presence of hMPV using real-time RT-PCR assays. The presence of hMPV was detected in 227 (25.9%) of the 878 children studied and may circulate year-round in the area, peaking during the winter,spring season. Younger children (aged less than 6 months) had the highest positive rate. Infections by hMPV showed similar epidemiology and clinical manifestations as for respiratory syncytial virus (RSV) and were found in high co-infections with RSV. Subgroup A2 hMPV was the most predominant genotype identified during the study period. This study indicates that hMPV is one of the major respiratory pathogens found in children in southwest China and vaccine development should be under consideration. Pediatr. Pulmonol. 2010; 45:824,831. © 2010 Wiley-Liss, Inc. [source]

Nocturnally retained zeaxanthin does not remain engaged in a state primed for energy dissipation during the summer in two Yucca species growing in the Mojave Desert

D. H. Barker
Abstract Differently oriented leaves of Yucca schidigera and Yucca brevifolia were characterized in the Mojave Desert with respect to photosystem II and xanthophyll cycle activity during three different seasons, including the hot and dry summer, the relatively cold winter, and the mild spring season. Photosynthetic utilization of a high percentage of the light absorbed in PSII was observed in all leaves only during the spring, whereas very high levels of photoprotective, thermal energy dissipation were employed both in the summer and the winter season in all exposed leaves of both species. Both during the summer and the winter season, when energy dissipation levels were high diurnally, xanthophyll cycle pools (relative to either Chl or other carotenoids) were higher relative to the spring, and a nocturnal retention of high levels of zeaxanthin and antheraxanthin (Z + A) occurred in all exposed leaves of both species. Although this nocturnal retention of Z + A was associated with nocturnal maintenance of a low PSII efficiency (Fv/Fm) on a cold winter night, pre-dawn Fv/Fm was high in (Z + A)-retaining leaves following a warm summer night. This indicates nocturnal engagement of Z + A in a state primed for energy dissipation throughout the cold winter night , while high levels of retained Z + A were not engaged for energy dissipation prior to sunrise on a warm summer morning. Possible mechanisms for a lack of sustained engagement of retained Z + A for energy dissipation at elevated temperatures are discussed. [source]

Diarrheal illness in a cohort of children 0,2 years of age in rural Bangladesh: I. Incidence and risk factors

Preeti Pathela
Abstract Aim: To describe clinical characteristics and age- and season-specific incidences of diarrheal episodes, and to evaluate risk factors associated with the occurrence of diarrheal disease. Methods: A total of 252 infants from rural Bangladesh were followed through household surveillance for 2 y from birth during the years 1993,1996. Demographic and household determinants were linked to the probability of illness using logistic regression models. Results: The overall incidence of diarrhea was 4.25 episodes per child per year. Peak rates of overall, acute, and persistent diarrhea occurred in the 6,11-mo and 12,17-mo age groups. Diarrheal rates peaked during the spring and summer. Among host-related characteristics, having a sibling in the household and having had prior diarrhea were significant risk factors for diarrhea. Among environmental characteristics, spring season remained a highly statistically significant risk factor for diarrhea. Conclusion: Diarrheal disease continues to be a substantial burden in young children in rural Bangladesh. Most diarrheal episodes are of short duration, and should primarily be treated with oral rehydration therapy to prevent diarrhea-related mortality. Improved knowledge of oral rehydration therapy, feeding during episodes to prevent further malnutrition, prolonged breastfeeding, and the keeping of livestock in corralled areas of the home are advocated. [source]

Cold tolerance and cold hardening strategy of the Japanese pine sawyer Monochamus alternatus (Coleoptera: Cerambycidae)

INSECT SCIENCE, Issue 4 2008
Jing Tian
Abstract The Japanese pine sawyer, Monochamus alternatus, is an important pine forest pest and vector transmitting the pine wilt nematode that causes pine wilt disease. Low temperatures in autumn, winter and spring often differentially affect mortality of M. alternatus larvae. In this paper, we mainly compared the differences of mortality and cold hardening of larvae from different seasons, based on supercooling point (SCP) and cumulative probability of individuals freezing (CPIF). The cold hardening of the larvae from autumn, winter and spring seasons were largely different. Correlations between mortality and CPIF of autumn and spring larvae were highest on day 1/4, and gradually decreased with prolonged exposure duration. This beetle's death mainly resulted from freezing in short exposure duration. However, the correlation between mortality and CPIF of winter larvae increased gradually with the prolonged exposure duration. Death did not mainly result from freezing in long exposure duration. Autumn larvae are more susceptible and adaptable than winter and spring larvae. Winter larvae have a slight freeze-tolerance trend. Our research showed that M. alternatus came into complex cold-hardening strategies under natural selection. Freeze avoidance is the primary strategy; with prolonged exposure duration to above SCP or < 0 °C, chill tolerance is more important; this is followed by freeze tolerance during harsh winters. [source]

Effects of differences in diet and seasonal changes on the fatty acid composition in fillets from farmed and wild sea bream (Sparus aurata L.) and sea bass (Dicentrarchus labrax L.)

Mustafa Yildiz
Summary The effects of dietary fatty acids and seasonal variation on the fatty acid profiles of farmed and wild sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax) were determined by analysis of their fillets. Farmed sea bream and sea bass were fed on the same commercial feeds all year. Fatty acid profiles in the fillets reflected the fatty acid profiles of the commercial feeds. The predominant fatty acids in the trial feeds, fillets of farmed and wild sea bream and sea bass were 16:0, 18:1n -9, 18:2n -6, 20:5n -3 and 22:6n -3. The fatty acid profiles in the fillets of farmed sea bream and sea bass did not differ (P > 0.05) except in the winter season compared with those of their wild counterparts. However, the content of eicosapentaenoic acid (20:5n -3), docosahexaenoic acid (22:6n -3) in the fillets of the farmed and wild sea bass were significantly (P < 0.05) higher than the farmed and wild sea bream. The wild sea bream had significantly (P < 0.05) higher total saturated fatty acid and monounsaturated fatty acid (MUFA) levels, and lower total n -6 and n -3 polyunsaturated fatty acid (PUFA) levels in winter than in the summer and spring seasons. Similarly, in the fillets of wild sea bass, total n -3 PUFA levels were significantly (P < 0.05) lower, and the MUFA levels were higher in winter than in the other seasons. These results indicate that the farmed fish fillets were good sources of n -3 PUFA in each of the three seasons. However, wild fish were good sources of n -3 PUFA in the spring and summer. [source]


ABSTRACT In this study, we evaluated chemical characteristics, fatty acid composition and conjugated linoleic acid (CLA) content of cow and goat cheeses from Northwest Argentina. Similar chemical and fatty acid composition were determined in milk and cheese of both species. Palmitic, oleic and myristic acids were the most abundant fatty acids in dairy products. CLA level averaged 0.85 and 0.96 in milk and 0.76 and 1.04 g/100 g of fatty acids in cheese of cow and goat, respectively. Cis -9,trans -11 was the major isomer present in both species. Significant differences in CLA desaturase activity were observed, showing a value of 0.068 and 0.064 in milk, and 0.077 and 0.071 in cheese of cow and goats, respectively. Good nutritional properties were determined for cheeses of both species, which are fed on natural pasture during spring and summer seasons. Goat's cheese represents a higher source of CLA for human consumers than cow's cheese, offering from 156.6 to 222.6 mg/ 100 g of sample. PRACTICAL APPLICATIONS The present work shows the fatty acid composition and chemical characteristics of two fresh cheeses manufactured with cow and goat milk. Animals were fed on natural pasture during summer and spring seasons. It is known that pasture increases conjugated linoleic acid (CLA) concentration in milk fat, and the content in cheese is directly related to it. The CLA content of dairy products for the human consumers was analyzed, showing goat cheese with high polyunsaturated fatty acid content, including CLA. Cow and goat fresh cheese offer CLA as many ripening products of different countries, as cheddar or hard cheeses. Lipid composition of food is related to many illnesses, but some compounds are beneficial to human health. The main sources of CLA are milk and cheeses, and in Northwest of Argentina, no data are reported about it, where artisanal cheeses are consumed by the population. Therefore, the atherogenicity index was determined as well. [source]

Impact of human metapneumovirus and human cytomegalovirus versus other respiratory viruses on the lower respiratory tract infections of lung transplant recipients

Giuseppe Gerna
Abstract Viral respiratory tract infections in lung transplant recipients may be severe. During three consecutive winter-spring seasons, 49 symptomatic lung transplant recipients with suspected respiratory viral infection, and 26 asymptomatic patients were investigated for presence of respiratory viruses either in 56 nasopharyngeal aspirate or 72 bronchoalveolar lavage samples taken at different times after transplantation. On the whole, 1 asymptomatic (3.4%) and 28 symptomatic (57.1%) patients were positive for human metapneumovirus (hMPV, 4 patients), influenza virus A (3 patients), and B (2 patients), respiratory syncytial virus (2 patients), human coronavirus (2 patients), human parainfluenza virus (2 patients), rhinovirus (5 patients), while 4 patients were coinfected by 2 respiratory viruses, and 5 were infected sequentially by 2 or more respiratory viruses. In bronchoalveolar lavage samples, hMPV predominated by far over the other viruses, being responsible for 60% of positive specimens, whereas other viruses were present in nasopharyngeal aspirates at a comparable rate. RT-PCR (detecting 43 positive samples/128 examined) was largely superior to monoclonal antibodies (detecting 17 positive samples only). In addition, HCMV was detected in association with a respiratory virus in 4/18 HCMV-positive patients, and was found at a high concentration (>105 DNA copies/ml) in 3/16 (18.7%) patients with HCMV-positive bronchoalveolar lavage samples and pneumonia. Coinfections and sequential infections by HCMV and respiratory viruses were significantly more frequent in patients with acute rejection and steroid treatment. In conclusion: (i) about 50% of respiratory tract infections of lung transplant recipients were associated with one or more respiratory viruses; (ii) hMPV largely predominates in bronchoalveolar lavage of symptomatic lung transplant recipients, thus suggesting a causative role in lower respiratory tract infections; (iii) RT-PCR appears to be the method of choice for detection of respiratory viruses in lung transplant recipients, (iv) a high HCMV load in bronchoalveolar lavage is a risk factor for viral pneumonia, suggesting some measure of intervention for the control of viral infection. J. Med. Virol. 78:408,416, 2006. © 2006 Wiley-Liss, Inc. [source]

Rotavirus hospitalisation in New Zealand children under 3 years of age

Keith Grimwood
Objective: To describe the epidemiology of severe rotavirus gastroenteritis and to estimate the hospitalisation rates of this illness in New Zealand children under 3 years of age. Methods: Children under 3 years of age with acute diarrhoea admitted to 1 of 8 study hospitals between 1 May 1998 and 30 April 2000 were surveyed. Their socio-demographic, treatment and length-of-stay data were recorded and stool samples tested by a rotavirus-specific enzyme-linked immunoassay. National hospital discharge data for infectious diarrhoea (International Classification of Diseases, ninth revision, 003,009) were reviewed, allowing population-based estimates for rotavirus-related hospitalisation in New Zealand. Results: Of 2019 enrolled children, 1138 (56.4%) provided stools for testing, and of these 485 (42.6%) tested rotavirus positive. Rotavirus detection varied significantly by age (26.8% for 0 to 5 months, 42.5% for 6 to 11 months and 52.1% for children aged 12 to 35 months; P < 0.001), and by season (51.2% in winter/spring vs. 24.5% in summer/autumn; P < 0.001). While those infected with rotavirus were more likely to be dehydrated (50.6% vs. 37.4%; P < 0.001), their median hospital stay was similar (1.0 vs. 2.0 days; P = 0.09) to other children with acute gastroenteritis. The estimated national hospitalisation rate for rotavirus diarrhoea in children under 3 years, standardised for age and season, was 634 (95% CI 597, 672) per 100 000. In New Zealand, rotaviruses result in 1 in 52 children being hospitalised by 3 years of age. Conclusions: Rotavirus diarrhoea is an important, potentially vaccine-preventable cause of hospitalisation in New Zealand children, especially during winter and spring seasons. [source]


Valerie D. Moulton
Abstract This study investigates how densities of ringed seals were affected by construction and oil production activities at Northstar, an artificial island built in the nearshore Alaskan Beaufort Sea. Intensive and replicated aerial surveys of seals on landfast ice were conducted during six spring seasons: for three seasons before island construction began (1997,1999); after a winter of intensive island construction (2000); and after more limited construction plus drilling (2001) and drilling plus oil production (2002). A Poisson regression model was used to examine seal densities relative to distance from Northstar after allowance for environmental covariates. Post hoc power analysis indicated that the study design and Poisson regression approach had high power to detect small-scale changes in seal densities near Northstar if such changes had occurred. However, seal densities during spring were not significantly affected by proximity to Northstar in 2000,2002. Habitat, temporal, and weather factors did have significant effects on seal densities. This study shows that effects of the Northstar oil development on local distribution of basking ringed seals are no more than slight, and are small relative to the effects of natural environmental factors. An understanding of environmental effects is essential when assessing potential impacts of industrial activity on ringed seals. [source]