Adaptive epigenetic memory of ancestral temperature regime in Arabidopsis thalianaThis paper is one of a selection of papers published in a Special Issue from the National Research Council of Canada – Plant Biotechnology Institute.

Botany ◽  
2009 ◽  
Vol 87 (6) ◽  
pp. 650-657 ◽  
Author(s):  
C. A. Whittle ◽  
S. P. Otto ◽  
M. O. Johnston ◽  
J. E. Krochko
Keyword(s):  
Temperature Regime ◽  
National Research Council ◽  
Plant Biotechnology ◽  
Environmental Parameters ◽  
Adaptive Responses ◽  
Temperature Regimes ◽  
Heat Treated ◽  
Epigenetic Phenomenon ◽  
Selection Of ◽  
Classical Genetics

Although certain acquired nongenetic (i.e., epigenetic) traits are known to be heritable in plants, little is known currently about whether environmental parameters can induce adaptive epigenetic responses in plants and whether such effects can persist through generations. We used an experimental design based on classical genetics principles to assess whether plants respond to the environmental conditions of their ancestors in an adaptive epigenetic manner. An extensive examination of genetically identical Arabidopsis thaliana (L.) Heynh lines exposed to mild heat (30 °C) or cold (16 °C) treatments in the parental and F1 generations revealed that the prior elevated temperature regime lead to a greater than fivefold improvement in fitness (seed production per individual) for plants exposed to heat in a later generation (F3). The heat-specific fitness improvements among F3 plants were observed even though the heat-treated parental and F1 generations were followed by a generation grown at a normal temperature (F2) and point towards a temperature-induced adaptive epigenetic phenomenon. No such adaptive responses were detected for cold-treated plants, indicating that there are distinctive biological processes inherent to these two temperature regimes. Overall, the data are consistent with the existence of an environmentally induced epigenetic and heritable adaptive response in plants.

Molecular cloning and characterization of Dbr1, a 2-alkenal reductase from Artemisia annuaThe nucleotide sequence reported in this article has been deposited in the GenBank database under accession No. FJ750460.This paper is one of a selection of papers published in a Special Issue from the National Research Council of Canada – Plant Biotechnology Institute.

Botany ◽  
2009 ◽  
Vol 87 (6) ◽  
pp. 643-649 ◽  
Author(s):  
Yansheng Zhang ◽  
Keat H. Teoh ◽  
Darwin W. Reed ◽  
Patrick S. Covello
Keyword(s):  
Double Bond ◽  
Artemisia Annua ◽  
Sequence Similarity ◽  
National Research Council ◽  
Plant Biotechnology ◽  
In Planta ◽  
Carbon Double Bond ◽  
Expressed Sequence ◽  
Selection Of

The molecular genetics of carbon–carbon double bond reduction in the plant Artemisia annua  L. was studied. Expressed sequence tags from this plant were investigated for sequences with similarity to known double-bond reductases. This resulted in the isolation of a cDNA, corresponding to the gene A. annua Dbr1 (Double bond reductase1), encoding a member of the medium chain dehydrogenase/reductase protein superfamily with sequence similarity to tobacco allyl alcohol dehydrogenase. Recombinant A. annua Dbr1 protein was purified from Escherischia coli and shown to catalyze the reduction of the carbon–carbon double bond of 2-alkenals. This activity included the reduction of the double bond at C11–C13 in the artemisinin precursor artemisinic aldehyde, albeit with unnatural stereochemistry. The substrate specificity, product stereochemistry, and expression pattern of A. annua Dbr1 point to its involvement in planta in the detoxification of 2-alkenals, which may be generated under oxidative stress conditions.

Over-expression of α-galactosidase in pea seeds to reduce raffinose oligosaccharide contentThis paper is one of a selection of papers published in a Special Issue from the National Research Council of Canada – Plant Biotechnology Institute.

Botany ◽  
2009 ◽  
Vol 87 (6) ◽  
pp. 526-532 ◽  
Author(s):  
Patricia L. Polowick ◽  
David S. Baliski ◽  
Cheryl Bock ◽  
Heather Ray ◽  
Fawzy Georges
Keyword(s):  
Intestinal Flora ◽  
National Research Council ◽  
Plant Biotechnology ◽  
Single Copy ◽  
Over Expression ◽  
Transgenic Lines ◽  
Pea Seeds ◽  
Plant Families ◽  
Coffea Arabica L ◽  
Selection Of

The raffinose family of oligosaccharides (RFO) is a series of complex carbohydrates stored in seeds of many plant families, especially in legumes. The digestive system of nonruminant animals, including that of humans, cannot break down all of the chemical bonds in these carbohydrates; therefore, catabolism is achieved anaerobically by intestinal flora. The resulting digestive problems reduce acceptance and limit the widespread consumption of these otherwise nutritious seeds. To demonstrate a solution to this problem, transgenic lines of pea ( Pisum sativum  L.) expressing the α-galactosidase gene from coffee ( Coffea arabica L.) were developed. Plants with a single copy of the inserted gene were selected, and two of these lines showed significant reductions of up to 40% in oligosaccharide content (raffinose, stachyose). Quantitative RT-PCR confirmed the presence of the α-galactosidase RNA in both leaves and cotyledons. Sugars were analyzed using whole seeds or only a portion of a seed; in the latter case, germination rates for each of the seeds analyzed were determined. The reduced raffinose contents did not affect germination rates, which remained very high (96%). The relative oligosaccharide contents of tissues within a seed also were determined; these were highest in the embryo axis, lower in the cotyledon and lowest in the seed coat.

Down-regulation of galactinol synthesis in oilseed Brassica napus leads to significant reduction of antinutritional oligosaccharidesThis paper is one of a selection of papers published in a Special Issue from the National Research Council of Canada – Plant Biotechnology Institute.

Botany ◽  
2009 ◽  
Vol 87 (6) ◽  
pp. 597-603 ◽  
Author(s):  
Cheryl Bock ◽  
Heather Ray ◽  
Fawzy Georges
Keyword(s):  
Brassica Napus ◽  
National Research Council ◽  
Plant Biotechnology ◽  
Antinutritional Factors ◽  
Mrna Levels ◽  
Brassica Napus L ◽  
Gene Encoding ◽  
Galactinol Synthase ◽  
Important Intermediate ◽  
Selection Of

The utility of defatted seed meal from many crops such as canola ( Brassica napus  L.) is limited by the presence of antinutritional factors, including sucrose galactosides, raffinose, and stachyose. Anaerobic breakdown of these sugars in the digestive tract of livestock is a major source of production of farm gases. In this report, the gene encoding galactinol synthase was isolated from B. napus and reintroduced into the same species in an antisense orientation to limit the production of galactinol, an important intermediate in the biosynthesis of raffinose and stachyose. This approach substantially reduced the accumulation of galactinol and stachyose in mature transgenic canola seed. Substantial changes in the mRNA levels of galactinol synthase and several sugar-related genes were also observed.

scholarly journals Properties of Extruded Snacks Prepared from Corn and Carrot Powder with Ascorbic Acid Addition

Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1367
Author(s):  
Valentina Obradović ◽  
Jurislav Babić ◽  
Verica Dragović-Uzelac ◽  
Antun Jozinović ◽  
Đurđica Ačkar ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Temperature Regime ◽  
External Source ◽  
Single Screw Extruder ◽  
Functional Value ◽  
Temperature Regimes ◽  
Starting Point ◽  
Extruded Snacks ◽  
New Type ◽  
Corn Snacks

The objective of this research was to investigate the potentiality of carrot powder (CP) utilization at levels 4, 6, or 8% as ingredient of corn snacks and evaluation of the extrusion influence on functionally important ingredients such as carotenoids (color), polyphenols, fiber, fat, and antioxidant activity. The influence of ascorbic acid (AA) as an external source at levels 0.5 and 1% on this particular extrusion was also investigated. A single-screw extruder at two temperature regimes (135/170/170 °C (E1) and 100/150/150 °C (E2)) carried out extrusion. The E1 temperature regime acted favorably on total polyphenol content and crude fiber, but fat preferred the E2 regime. Extrusion, especially the E1 temperature regime, increased the extractability of carotenoids. Ascorbic acid degraded during extrusion, but it still provided protection to carotenoids and color attributes of extrudates. Snacks with increased nutritional and functional value due to carrot powder addition were successfully produced, which is a starting point for production of a new type of extruded snacks.

scholarly journals Fungal and Bacterial Diversity Patterns of Two Diversity Levels Retrieved From a Late Decaying Fagus sylvatica Under Two Temperature Regimes

2021 ◽  
Vol 11 ◽  
Author(s):  
Sarah Muszynski ◽  
Florian Maurer ◽  
Sina Henjes ◽  
Marcus A. Horn ◽  
Matthias Noll
Keyword(s):  
Species Richness ◽  
Bacterial Community ◽  
Mass Loss ◽  
Community Composition ◽  
Fagus Sylvatica ◽  
Temperature Regime ◽  
Community Diversity ◽  
Interaction Patterns ◽  
Temperature Regimes ◽  
Natural Diversity

Environmental fluctuations are a common occurrence in an ecosystem, which have an impact on organismic diversity and associated ecosystem services. The aim of this study was to investigate how a natural and a species richness-reduced wood decaying community diversity were capable of decomposing Fagus sylvatica dead wood under a constant and a fluctuating temperature regime. Therefore, microcosms with both diversity levels (natural and species richness-reduced) were prepared and incubated for 8 weeks under both temperature regimes. Relative wood mass loss, wood pH, carbon dioxide, and methane emissions, as well as fungal and bacterial community compositions in terms of Simpson‘s diversity, richness and evenness were investigated. Community interaction patterns and co-occurrence networks were calculated. Community composition was affected by temperature regime and natural diversity caused significantly higher mass loss than richness-reduced diversity. In contrast, richness-reduced diversity increased wood pH. The bacterial community composition was less affected by richness reduction and temperature regimes than the fungal community composition. Microbial interaction patterns showed more mutual exclusions in richness-reduced compared to natural diversity as the reduction mainly reduced abundant fungal species and disintegrated previous interaction patterns. Microbial communities reassembled in richness-reduced diversity with a focus on nitrate reducing and dinitrogen-fixing bacteria as connectors in the network, indicating their high relevance to reestablish ecosystem functions. Therefore, a stochastic richness reduction was followed by functional trait based reassembly to recover previous ecosystem productivity.

scholarly journals Selection of the chemical composition of steels and their thermal hardening mode using a computer program

2021 ◽  
pp. 59-65
Author(s):  
D. M. Berdiev ◽  
M. A. Uмаrоvа ◽  
A. A. Yusupov
Keyword(s):  
Wear Resistance ◽  
Chemical Composition ◽  
Computer Program ◽  
Sliding Friction ◽  
Thermal Hardening ◽  
Abrasive Particles ◽  
Density Of Dislocations ◽  
Heat Treated ◽  
Final Tempering ◽  
Selection Of

The relationships between the parameters of the structure of heat‑treated steels and their abrasive wear resistance are established. At all temperatures of the final tempering of hardened steel, there is a direct relationship between its structure parameters (the number of elements in a solid solution, the density of dislocations, the size of cementite particles and the intercementite distance) and wear resistance when sliding friction against loose abrasive particles. A computer program has been developed to select the chemical composition of the steel grade and methods of thermal hardening in order to ensure the required wear resistance.

scholarly journals Thermal stability analysis of particles incorporated in cirrus crystals and of non-activated particles in between the cirrus crystals: Comparing clean and polluted air masses

2003 ◽  
Vol 3 (4) ◽  
pp. 3659-3679 ◽  
Author(s):  
M. Seifert ◽  
J. Ström ◽  
R. Krejci ◽  
A. Minikin ◽  
A. Petzold ◽  
...  
Keyword(s):  
Temperature Regime ◽  
Water Soluble ◽  
Cloud Formation ◽  
Residual Fraction ◽  
Volatile Fraction ◽  
Air Masses ◽  
Temperature Regimes ◽  
Soluble Sulfate ◽  
Indirect Information ◽  
Cold Case

Abstract. A thermal volatility technique is used to provide indirect information about the chemical composition of the aerosol involved in cirrus cloud formation. The fraction of particles that disappears after being heated to 125°C is termed volatile and the fraction that disappears between 125 and 250°C is termed semi-volatile. Particles that still remain after being heated to 250°C make up the non-volatile fraction. The thermal composition of residual particles remaining from evaporated cirrus crystals is presented and compared to interstitial aerosol particles (non-activated particles in between the cirrus crystals) for two temperature regimes (cold: T<235 K, warm: 235<T<250 K), based on in-situ observations. The observations were conducted in cirrus clouds in the Southern Hemisphere (SH) and Northern Hemisphere (NH) midlatitudes during the INCA project. In the cold temperature regime, the non-volatile fraction of the residual particles was typically in the range 10 to 30% in the NH and 30 to 40% in the SH. In the warm temperature regime, the non-volatile residual fraction was typically 10 to 30% (NH) and 20 to 40% (SH). At high crystal number densities the non-volatile fraction in both temperature regimes was even higher: in the range of 30 to 40% (NH) and 40 to 50% (SH). The semi-volatile fraction was typically less than 10% in both hemispheres, causing the volatile fraction to essentially be a complement to the non-volatile fraction. In terms of the fractioning into the three types of particles, the SH cold case is clearly different compared to the other three cases (the two warm cases and the cold NH case), which share many features. In the NH data the distribution of different particle types does not seem to be temperature dependent. In all the cases, the non-volatile fraction is enriched in the residual particles compared to the fractions observed for the interstitial particles. This enrichment corresponds to about 15 (NH) and 30 (SH) percent units in the two cold cases and to 15–25 (NH) and 25–35 (SH) percent units in the two warm cases. In the NH cold case, there is a clear relation between the fractions observed in the interstitial particles and what is observed in the residual particles. The observed large fractions of non-volatile particles show that particles forming ice crystals are not entirely made up of water-soluble sulfate particles.

Selection of Environmental Parameters for Offshore Jacket Platform Design in Malaysia

2011 ◽  
Author(s):  
B. Idrus ◽  
N. S. Potty ◽  
M. F. A. Hamid ◽  
Z. Nizamani ◽  
N. J. Cossa
Keyword(s):  
Environmental Parameters ◽  
Jacket Platform ◽  
Platform Design ◽  
Offshore Jacket Platform ◽  
Selection Of

scholarly journals Assessing the role of two populations of Aedes japonicus japonicus for Zika virus transmission under a constant and a fluctuating temperature regime

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Uros Glavinic ◽  
Jasmin Varga ◽  
Anca Ioana Paslaru ◽  
Jeannine Hauri ◽  
Paul Torgerson ◽  
...  
Keyword(s):  
Constant Temperature ◽  
Temperature Regime ◽  
Zika Virus ◽  
Incubation Temperature ◽  
Transmission Rate ◽  
Control Measures ◽  
Fluctuating Temperature ◽  
Laboratory Conditions ◽  
Temperature Regimes ◽  
Two Populations

Abstract Background Since the huge epidemic of Zika virus (ZIKV) in Brazil in 2015, questions were raised to understand which mosquito species could transmit the virus. Aedes aegypti has been described as the main vector. However, other Aedes species (e.g. Ae. albopictus and Ae. japonicus) proven to be competent for other flaviviruses (e.g. West Nile, dengue and yellow fever), have been described as potential vectors for ZIKV under laboratory conditions. One of these, the Asian bush mosquito, Ae. japonicus, is widely distributed with high abundances in central-western Europe. In the present study, infection, dissemination and transmission rates of ZIKV (Dak84 strain) in two populations of Ae. japonicus from Switzerland (Zürich) and France (Steinbach, Haut-Rhin) were investigated under constant (27 °C) and fluctuating (14–27 °C, mean 23 °C) temperature regimes. Results The two populations were each able to transmit ZIKV under both temperature regimes. Infectious virus particles were detected in the saliva of females from both populations, regardless of the incubation temperature regime, from 7 days post-exposure to infectious rabbit blood. The highest amount of plaque forming units (PFU) (400/ml) were recorded 14 days post-oral infection in the Swiss population incubated at a constant temperature. No difference in terms of infection, dissemination and transmission rate were found between mosquito populations. Temperature had no effect on infection rate but the fluctuating temperature regime resulted in higher dissemination rates compared to constant temperature, regardless of the population. Finally, transmission efficiency ranged between 7–23% and 7–10% for the constant temperature and 0–10% and 3–27% under fluctuating temperatures for the Swiss and the French populations, respectively. Conclusions To the best of our knowledge, this is the first study confirming vector competence for ZIKV of Ae. japonicus originating from Switzerland and France at realistic summer temperatures under laboratory conditions. Considering the continuous spread of this species in the northern part of Europe and its adaptation at cooler temperatures, preventative control measures should be adopted to prevent possible ZIKV epidemics.

Environmental Control of Flowering of Boronia megastigma (Rutaceae) and Hypocalymma angustifolium (Myrtaceae)

1994 ◽  
Vol 42 (2) ◽  
pp. 219 ◽  
Author(s):  
JS Day ◽  
BR Loveys ◽  
D Aspinall
Keyword(s):  
Temperature Regime ◽  
Flower Development ◽  
Vegetative Growth ◽  
Environmental Control ◽  
Night Temperature ◽  
Root Temperature ◽  
Aerial Parts ◽  
Temperature Regimes ◽  
Controlled Flowering

The flowering responses of Boronia megastigma Nees (Rutacae) and Hypocalymma angustifolium Endl. (Myrtaceae) to different photoperiod and temperature regimes were similar despite the fact that these species are from different families. No flowers reached anthesis in a temperature regime of 25°C day/17°C night but flowering of both species occurred in a cool temperatures (17°C day/9°C night). Photoperiod had no effect on flowering at the temperatures tested. Ten weeks of cool temperatures (17°C day/9°C night) were required for a maximum number of flowers to reach anthesis on H. angustifolium plants whereas B. megastigma plants required 15 weeks. Flower development in both species was inhibited by a large difference between day and night temperature (21°C day/5°C night) and promoted if the day/night difference was reversed (9°C day/17°C night). The temperature of the aerial parts of the plant controlled flowering, whereas vegetative growth was controlled by root temperature. Therefore, while a reduction in vegetative growth naturally coincides with the production of flowers, these events are not necessarily linked.

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