INFLUENCE DE L’ENRICHISSEMENT CARBONÉ ET DE SON MODE DE DISTRIBUTION SUR L’ÉVOLUTION DES ÉCHANGES GAZEUX DE LA TOMATE DE SERRE

1990 ◽  
Vol 70 (1) ◽  
pp. 345-356 ◽  
Author(s):  
A. DUGAL ◽  
S. YELLE ◽  
A. GOSSELIN
Keyword(s):  
Stomatal Conductance ◽  
Lycopersicon Esculentum ◽  
Net Photosynthesis ◽  
Long Term Effects ◽  
Gas Exchanges ◽  
Tomato Seedlings ◽  
Lycopersicon Esculentum Mill ◽  
Échanges Gazeux ◽  
Very High

Net photosynthesis, stomatal conductance, internal CO2 concentration and transpiration were measured on the fifth well-developed and excised leaf of tomato seedlings (Lycopersicon esculentum Mill. ’Vedettos’) 48–83 d old. These measurements were taken in order to monitor the evolution of the gas exchanges of seedlings exposed to concentrations of 330 or 1000 ppm, continuously, to 1000 ppm from 06: 00 h to 10: 00 h or to 1000 and 330 ppm alternately every 2 h. CO2 enrichment substantially increased the net photosynthesis rate of the seedlings, particularly at the beginning of the experiment. The long-term effects of CO2 enrichment subsided after a few weeks of treatment. Intermittent CO2 enrichment is partially helpful in remedying the loss of effectiveness of the CO2 after a long period of enrichment. High CO2 concentrations reduced the opening of the stomata. Our work shows that maintaining a high internal CO2 content in the leaves would indirectly reduce the stomatal conductance of the seedlings. However, our results show that the long-term loss of photosynthetic efficiency in the enriched seedlings cannot be attributed solely to an increase in the resistance of the stomata, since the internal CO2 concentration of the leaves remains very high regardless of which method of CO2 enrichment is used. Continuous CO2 enrichment improved the water uptake efficiency of the seedlings.Key words: Carbon dioxide, intermittent enrichment, gas exchanges, tomato, greenhouse, Lycopersicon esculentum Mill.

The effects of ultraviolet-B radiation and carbon dioxide on growth and photosynthesis of tomato

1997 ◽  
Vol 75 (2) ◽  
pp. 213-219 ◽  
Author(s):  
Xiuming Hao ◽  
Beverley A. Hale ◽  
Douglas P. Ormrod
Keyword(s):  
Lycopersicon Esculentum ◽  
Leaf Area ◽  
Plant Height ◽  
Net Photosynthesis ◽  
Dry Weight ◽  
Ultraviolet B ◽  
Radiation Level ◽  
Ultraviolet B Radiation ◽  
Lycopersicon Esculentum Mill ◽  
Uv Absorbing Compounds

Tomato (Lycopersicon esculentum Mill.) plants were exposed, in controlled environments with 2.7 kJ/(m2 ∙ day) background ultraviolet-B (UV-B) radiation from fluorescent and incandescent lamps, to ambient (380 μL ∙ L−1) or elevated (600 μL−1) CO2 combined with a total of 7.2 or 13.1 kJ/(m2 ∙ day) UV-B radiation to determine effects on growth and photosynthesis. Ten consecutive days of exposure to the higher level of UV-B significantly reduced total and stem dry weight, leaf area, and plant height compared with the lower level. Only leaf area and plant height were significantly reduced after 19 consecutive days of exposure. To investigate whether plants recover from UV-B damage, the UV-B exposures were halted for 3 days after 19 days of UV-B exposure and then restarted for a further 2 days. The largest reduction in plant growth was found after 3 days with no UV-B followed by 2 days of the higher level of UV-B. Plants did not recover from UV-B damage during the 3 days with background UV-B. Significant CO2xUV-B interactions were detected on stem dry weight after 10 consecutive days of the higher level of UV-B and on total dry weight, leaf dry weight, stem dry weight, and plant height after 3 days with no UV-B followed by 2 days of the higher level of UV-B. The higher dose of enhanced UV-B resulted in more severe damage at 600 μL ∙ L−1 CO2, than at ambient CO2. The higher level of UV-B did not affect the leaf net photosynthesis rate on a leaf area basis, although this UV-B level may have inhibited tomato growth through reducing the photosynthetic area. UV-absorbing compounds in leaves in the highest UV-B radiation level for 19 days were greater than for leaves with the lower dose. These UV-absorbing compounds in the higher UV-B dose diminished more than in the lower dose plants during the 3 days without UV-B. The UV-absorbing compounds maintained by plants exposed to the highest level of UV-B radiation may have protected plants from UV-B damage, particularly between 10 and 19 consecutive days of exposure. Key words: CO2, growth, Lycopersicon esculentum Mill., photosynthesis, tomato, ultraviolet-B radiation (UV-B), UV-absorbing compounds.

scholarly journals Comparison of Radiographic and Surface Topography Measurements in Adolescents with Idiopathic Scoliosis

2012 ◽  
Vol 6 (1) ◽  
pp. 261-265 ◽  
Author(s):  
Jason M Frerich ◽  
Kristen Hertzler ◽  
Patrick Knott ◽  
Steven Mardjetko
Keyword(s):  
Idiopathic Scoliosis ◽  
Surface Topography ◽  
Gold Standard ◽  
Comparison Analysis ◽  
Long Term Effects ◽  
Radiographic Measurements ◽  
Curve Magnitude ◽  
Standard Radiographs ◽  
Very High

Purpose: In patients with adolescent idiopathic scoliosis (AIS), radiographic surveillance is the gold standard of assessing spinal deformity, but has negative long-term effects. The Formetric 4D surface topography system was compared to standard radiography as a safer option for evaluating patients with AIS. Methods: Fourteen volunteers with typical AIS patient stature had 30 repeated Formetric 4D measurements taken, and reproducibility was assessed. Sixty-four patients with AIS were then enrolled during routine clinic visits. Evaluation included standard radiographs and surface topography measurements. A comparison analysis was performed. Results: When assessing same-day repeated scans, a standard deviation of +/- 3.4 degrees for scoliosis curve measurements was determined, and the Reliability Coefficient (Cronbach) was very high (0.996). Cobb angles measured with the Formetric 4D differed from radiographic measurements by an average of 9.42 (lumbar) and 6.98 (thoracic) degrees, while the correlation between the two measurements was strong (95% confidence interval [CI]), 0.758 (lumbar) and 0.872 (thoracic) respectively. Conclusions: The Formetric 4D is comparable to radiography in terms of its test-retest reproducibility. Although this device does not predict curve magnitude exactly, the predictions correlate strongly with the Cobb angles determined from radiographs. It can be reliably used in the surveillance of patients with AIS.

EDIBLE PINK-FRUITED TOMATO (LYCOPERSICON ESCULENTUM MILL. CONVAR. ESCULENTUM VAR. ROSEUM KHRAP.): SOURCE MATERIAL FOR BREEDING

2020 ◽  
Author(s):  
I.A. KHRAPALOVA ◽  
Keyword(s):  
Lycopersicon Esculentum ◽  
Growth Habit ◽  
Agronomic Traits ◽  
Fruit Shape ◽  
Stem Growth ◽  
Local Varieties ◽  
Lycopersicon Esculentum Mill ◽  
Inflorescence Morphology ◽  
Botanical Classification

This catalogue contains a description of morphological, biological and useful agronomic traits in 153 accessions of cultivated edible tomato (Lycopersicon esculentum Mill.) with pink fruits from the VIR collection. The data were obtained in the course of many years in winter rack glasshouses and plastic greenhouses at Pushkin and Pavlovsk Laboratories of VIR (St. Petersburg). The catalogue has been intended to help breeders, researchers, experts and farmers in gaining knowledge about pink-fruited tomato genetic resources that have been accumulated in the VIR collection for almost a hundred years. Cultivars developed through scientific breeding and local varieties are quite diverse in their earliness, fruit shape and size, stem growth habit and pattern, leaf and inflorescence morphology, etc. Their diversity described in the catalogue has been systemized in accordance with the botanical classification developed by the author of the catalogue on the basis of long-term research into the collection.

Condition assessment of in situ elastomeric bearings

2021 ◽  
Author(s):  
Edoardo Rossi ◽  
Michele D’Amato ◽  
Rosario Gigliotti ◽  
Marco Sebastiani
Keyword(s):  
Modal Analysis ◽  
Extreme Events ◽  
Seismic Isolation ◽  
Operational Modal Analysis ◽  
Structural Components ◽  
Long Term Effects ◽  
Elastomeric Bearings ◽  
Very High

<p>Elastomeric bearings used as seismic isolation devices are key elements in the protection of constructions against earthquakes. They enable structures to exhibit very high performances when subject to extreme events, preventing damage both to structural and non-structural components. Their characteristics, however, are prone to change with time due to long term effects such as aging. Regular inspection and monitoring of their state are thus fundamental activities needed to ensure the required performances. The present work reviews the most common strategies adopted for such purpose, including visual inspections, Operational Modal Analysis (OMA), and quick release tests. An innovative characterisation method is also presented. Such method, with the use of a nanoindenter, enables testing of a small rubber sample (3 mm in diameter) cored from a device. Its suitability is confirmed through a comparison of the same device tested in a traditional setup.</p>

scholarly journals Twenty-Five and Thirty-Five Year Follow up of First Admissions to Mental Hospital

1968 ◽  
Vol 13 (3) ◽  
pp. 219-229 ◽  
Author(s):  
M. N. Beck
Keyword(s):  
Prince Edward Island ◽  
Mental Hospital ◽  
Long Term Effects ◽  
Nineteen Thirties ◽  
Needed Information ◽  
Nineteen Forties ◽  
Long Term Follow Up ◽  
Very High

This has been a report of a study designed to assess the feasibility of long-term follow-up studies on Prince Edward Island. Cohorts of patients first admitted to the Island's only mental hospital during the early nineteen-thirties and early nineteen-forties were followed in retrospect in order to determine, a) the course and outcome of the major disorders over periods ranging up to thirty-five years and, b) the long-term effects of these disorders upon the families of the patients. Needed information was gathered through a review of hospital records, a search for death records and community interviews. The results of the study suggest that lifetime prognosis in the absence of modern treatment methods may be even worse than believed by most professionals working in the field. As might be expected the outlook was found to be particularly grave for schizophrenia. Success in following up a very high proportion of the cases over several decades supports the belief that Prince Edward Island offers unusual opportunities for studies of this kind.

Florida Oil Spill Impact on the Buzzards Bay Benthic Fauna: West Falmouth

1978 ◽  
Vol 35 (5) ◽  
pp. 717-730 ◽  
Author(s):  
Howard L. Sanders
Keyword(s):  
Species Composition ◽  
Oil Spill ◽  
Benthic Fauna ◽  
Sampling Period ◽  
Subtidal Zone ◽  
Long Term Effects ◽  
Homogeneous Pattern ◽  
Very High ◽  
Hierarchical Pattern

No matter what criterion is used to measure the effects of the Florida oil spill, the densities and species composition and the array of statistical methods demonstrate that the same hierarchical pattern emerges. Densities and species composition remain stable over time at the minimally oiled and unoiled stations, but display considerable fluctuations and marked changes at the more heavily oiled stations. With simple presence or absence data, highest fidelity is present at the marginally oiled stations, lower fidelity at the intermediately oiled stations, and lowest fidelity at the severely oiled stations. The discrepancy index measures mean yearly differences in faunal composition at each of the stations. Very large and large differences are documented for the severely and intermediately oiled stations but only small differences are found for the marginally oiled stations. The coefficient of variation is a measure of faunal variability throughout the entire sampling period for each of the stations. Faunal variation remains very high at the severely and intermediately oiled stations but low at the marginally oiled sites. Cluster analysis reveals profound temporal changes in the fauna from samples collected at the severely and intermediately oiled stations but demonstrates a much more homogeneous pattern with only small seasonal changes from samples obtained at the marginally oiled stations. Key words: benthos, hydrocarbon, intertidal zone, long-term effects, petroleum, pollution, statistics, subtidal zone

scholarly journals Effects of different floor housing systems on the welfare of fast-growing broilers with an extended fattening period

2018 ◽  
Vol 61 (1) ◽  
pp. 9-16 ◽  
Author(s):  
Enver Çavuşoğlu ◽  
Metin Petek ◽  
İbrahima Mahamane Abdourhamane ◽  
Ahmet Akkoc ◽  
Ersin Topal
Keyword(s):  
Housing System ◽  
Long Term Effects ◽  
Hybrid Male ◽  
Fast Growing ◽  
Housing Systems ◽  
Slaughter Age ◽  
The Relationship ◽  
Very High ◽  
Slat Floor

Abstract. This study was made to investigate the long-term effects of different floor housing systems on the welfare of fast-growing broilers. The experiment was performed on 210-day-old fast-growing hybrid male chickens with identical conditions until 47 days of age. Animal-based welfare parameters were measured to investigate the welfare level in the group housed on deep litter, a litter and slat system, and a slatted floor, with five replicates for each group. Results showed that the main welfare indicators in live birds, such breast dirtiness, plumage score, footpad lesion, and hock burn lesion, were negatively affected in broilers kept on conventional deep-litter floor housing. But hemorrhage or lesion scores of the breast and shoulder of broilers in slat floor housing were found to be significantly greater than in conventional deep litter as a result of a heavy body weight at a greater slaughter age (p<0.05). Pathologically, the prevalence of footpad and hock joint dermatitis was very high in the deep-litter housing system. Femoral head necrosis was not observed in any floor housing group. The results indicated that keeping broilers on a slat flooring system is preferable for younger slaughter ages and for a lighter slaughter weight. When considering the relationship between animal welfare and production economy, moving from one floor house system to another floor housing system should be carefully weighted in future decisions. Moreover, further investigations are needed in order to examine the incidence of joint and bone problems with muscle inflammation in heavier broilers in commercial conditions.

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