Environmental constraints to photosynthesis in ex vitro plants

1994 ◽  
pp. 1-18 ◽  
Author(s):  
M. M. Chaves
Keyword(s):  
Environmental Constraints ◽  
Ex Vitro

Preliminary Report of a Comparative Study of Seminiferous Tubular Epithelium from Rats Flown on Cosmos 1887 and SL3

1988 ◽  
Vol 46 ◽  
pp. 276-277
Author(s):  
Walter J. Sapp ◽  
D.E. Philpott ◽  
C.S. Williams ◽  
K. Kato ◽  
J. Stevenson ◽  
...  
Keyword(s):  
Space Flight ◽  
Physiological Response ◽  
Preliminary Report ◽  
Complete Recovery ◽  
Environmental Constraints ◽  
Tubular Epithelium ◽  
Testicular Weight ◽  
Testicular Morphology ◽  
Normal Offspring ◽  
Rats And Mice

Space flight, with its unique environmental constraints such as immobilization, decreased and increased pressures, and radiation, is known to affect testicular morphology and spermatogenesis. Selye, summarized the manifestations of physiological response to nonspecific stress and he pointed out that atrophy of the gonads always occurred. Reports of data collected from two dogs flown in space for 22 days (Cosmos 110) indicate that there was an increase of 30 to 70% atypical spermatozoa when compared to ground based controls. Seventy-five days after the flight the abnormalities had decreased to the high normal value of 30% and mating of these dogs after this period produced normal offspring, suggesting complete recovery. Effects of immobilization and increased gravity were investigated by spinning rats and mice at 2x g for 8-9 weeks. A decrease in testicular weight was noted in spun animals when compared to controls. Immobilization has been show to cause arrest of spermatogenesis in Macaca meminstrins.

Ecological Limits and the Meaning of Freedom: A Defense of Liberty as Non-Domination

2017 ◽  
Vol 3 (3) ◽  
pp. 33-49 ◽  
Author(s):  
Augustin Fragnière
Keyword(s):  
Conceptual Analysis ◽  
Environmental Policies ◽  
Environmental Constraints ◽  
Political Arena ◽  
Individual Liberty ◽  
Philosophical Debate ◽  
Political Issues ◽  
Global Environmental Problems ◽  
Global Environmental ◽  
Two Alternatives

It is now widely acknowledged that global environmental problems raise pressing social and political issues, but relatively little philosophical attention has been paid to their bearing on the concept of liberty. This must surprise us, because the question of whether environmental policies are at odds with individual liberty is bound to be controversial in the political arena. First, this article explains why a thorough philosophical debate about the relation between liberty and environmental constraints is needed. Second, based on Philip Pettit’s typology of liberty, it assesses how different conceptions of liberty fare in a context of stringent ecological limits. Indeed, a simple conceptual analysis shows that some conceptions of liberty are more compatible than others with such limits, and with the policies necessary to avoid overshooting them. The article concludes that Pettit’s conception of liberty as non-domination is more compatible with the existence of stringent ecological limits than the two alternatives considered.

Mitigating Environmental Constraints at Airports through Long Term Planning: A Decision Support Approach

2004 ◽  
Vol 12 (2) ◽  
pp. 107-124 ◽  
Author(s):  
Paul Upham ◽  
Yingjie Yang ◽  
David Raper ◽  
Callum Thomas ◽  
David Gillingwater ◽  
...  
Keyword(s):  
Decision Support ◽  
Environmental Constraints

DESIGN-BUILD: AN EFFECTIVE APPROACH FOR ARCHITECTURE STUDIO EDUCATION

2018 ◽  
Vol 12 (2) ◽  
pp. 146 ◽  
Author(s):  
Nabil Mohareb ◽  
Sara Maassarani
Keyword(s):  
Material Selection ◽  
Environmental Constraints ◽  
Design Project ◽  
Construction Methods ◽  
Physical Scale ◽  
Design Build ◽  
Simulation Results ◽  
Education Process ◽  
Real Target

Current architecture studios are missing an important phase in the education process, which is constructing the students’ conceptual ideas on a real physical scale. The design-build approach enables the students to test their ideas, theories, material selection, construction methods, environmental constraints, simulation results, level of space functionality and other important aspects when used by real target clients in an existing context. This paper aims to highlight the importance of using the design-build method through discussing a design project case study carried out by the Masters of Architecture design programme students at Beirut Arab University, who have built prototype units for refugees on a 1:1 scale.

Patrones de crecimiento de Cinchona officinalis in vitro y ex vitro; respuestas de plántulas micropropagadas y de semillas.

2017 ◽  
Vol 35 (1-2) ◽  
pp. 73-82
Author(s):  
Carlos Iván Espinosa ◽  
Gabriel Ríos
Keyword(s):  
Ex Vitro

El uso de herramientas biotecnológicas como la micropropagación se constituye en una alternativa de reproducción de especies amenazadas y con tamaños poblacionales reducidos. Sin embargo, uno de los problemas críticos en el uso de la micropropagación como herramienta de reproducción es la calidad de las plántulas resultantes en cuanto a su crecimiento y vigor. En el presente trabajo se evalua los efectos de la micropropagación sobre los patrones de crecimiento y sobrevivencia de plán­tulas in vitro de Cinchona officinalis L., una especie que ha sido fuertemente impactada por procesos de tala dentro de bosques naturales durante la época de la colonia. Se realizó un monitoreo de un total de 120 plántulas in vitro y 1988 plántulas ex vitro por 8 meses a partir del último repique. Adi­cionalmente, en cada plántula se contabilizó la cantidad de brotes axilares. Los resultados obtenidos mostraron un efecto remanente de los procesos de micropropagación, los cuales inicialmente inciden en la cantidad de brotes de las plántulas y en el crecimiento; sin embargo, este efecto no influye de forma negativa en la sobrevivencia de las plántulas durante la fase ex vitro

The Economic Cost of Hydropower Environmental Constraints Under Decreasing Price Volatility

2020 ◽  
Author(s):  
Hannu Huuki ◽  
Santtu Karhinen ◽  
Faisal Ashraf ◽  
Ali Torabi Haghighi ◽  
Hannu Marttila
Keyword(s):  
Price Volatility ◽  
Economic Cost ◽  
Environmental Constraints

Long-term in vitro Storage Technique of Valuable Birch Genotypes and Plant Production on its Basis

2019 ◽  
pp. 57-67
Author(s):  
T.M. Tabatskaya ◽  
N.I. Vnukova
Keyword(s):  
Plant Production ◽  
High Survival ◽  
Ex Vitro ◽  
Regenerative Capacity ◽  
In Vitro Storage ◽  
Interspecific Differences ◽  
Regenerated Plants ◽  
Growing Conditions

A technique for the long-term (up to 27 years) in vitro storage of valuable birch genotypes under normal (25 °C, 2.0 klx, 16-h day and 8-h night) and low temperature (4 °C, 0.5 klx, 6-h day and 18-h night) growing conditions on hormone-free media has been described. The study explored for the first time the influence of different strategies to store the clones of Betula pubescens and B. pendula var. сarelica (6 genotypes) on the regenerative capacity of collection samples, adaptive potential of regenerated plants and plant production by the in vitro and ex vitro techniques. It was established that both storage strategies provided a persistently high survival rate (82-100%) and regenerative capacity of in vitro shoots (the multiplication coefficient of 4.2-6.3 and rhizogenic activity of 90-100%). The clones retained their characteristics of height growth under the in vitro and ex vitro conditions, and demonstrated intraclonal homogeneity and lack of signs of somaclonal variability. The plants showed substantial interspecific differences at the stage of multiplication and transfer to the greenhouse. The highest percentage of acclimated plants (75-98% depending on the clone genotype) was obtained after planting of micro plants straight in the greenhouse, which simplified the technology and made plant production less costly. long-term in vitro storage, birch, species, genotype, micropropagation, ex vitro adaptation, plant material

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