scholarly journals Optimum temperature for floral terpene emissions tracks the mean temperature of the flowering season

2015 ◽  
Vol 42 (9) ◽  
pp. 851 ◽  
Author(s):  
Gerard Farré-Armengol ◽  
Iolanda Filella ◽  
Joan Llusià ◽  
Ülo Niinemets ◽  
Josep Peñuelas
Keyword(s):  
Optimum Temperature ◽  
Dynamic Headspace ◽  
Flowering Season ◽  
Physiological Adaptations ◽  
Dynamic Headspace Sampling ◽  
Different Seasons ◽  
Floral Volatile ◽  
The Mean ◽  
Mediterranean Plant ◽  
Temperature Responses

Emissions of volatiles from leaves exhibit temperature dependence on maximums, but the optimum temperatures for the release of floral volatiles and the mechanism(s) of optimising these emissions have not been determined. We hypothesised that flowers have an optimum temperature for the emission of volatiles and, because the period of flowering varies highly among species, that this optimum is adapted to the temperatures prevailing during flowering. To test these hypotheses, we characterised the temperature responses of floral terpene emissions of diverse widespread Mediterranean plant species flowering in different seasons by using dynamic headspace sampling and analysis with GC-MS. The floral emissions of terpenes across species exhibited maximums at the temperatures corresponding to the season of flowering, with the lowest optimal temperatures observed in winter-flowering and the highest in summer-flowering species. These trends were valid for emissions of both total terpenes and the various terpene compounds. The results show that the optimum temperature of floral volatile emissions scales with temperature at flowering, and suggest that this scaling is the outcome of physiological adaptations of the biosynthetic or emission mechanisms of flowers.

scholarly journals Developing a Method for the Collection and Analysis of Burnt Remains for the Detection and Identification of Ignitable Liquid Residues Using Body Bags, Dynamic Headspace Sampling, and TD-GC×GC-TOFMS

Separations ◽  
2018 ◽  
Vol 5 (3) ◽  
pp. 46 ◽  
Author(s):  
Katie Nizio ◽  
Shari Forbes
Keyword(s):  
Forensic Analysis ◽  
Headspace Sampling ◽  
Dynamic Headspace ◽  
Flight Mass Spectrometry ◽  
Detection And Identification ◽  
Dynamic Headspace Sampling ◽  
Fire Debris ◽  
Primary Focus ◽  
Ignitable Liquid ◽  
And Storage

In cases of suspected arson, a body may be intentionally burnt to cause loss of life, dispose of remains, or conceal identification. A primary focus of a fire investigation, particularly involving human remains, is to establish the cause of the fire; this often includes the forensic analysis of fire debris for the detection of ignitable liquid residues (ILRs). Commercial containers for the collection of fire debris evidence include metal cans, glass jars, and polymer/nylon bags of limited size. This presents a complication in cases where the fire debris consists of an intact, or partially intact, human cadaver. This study proposed the use of a body bag as an alternative sampling container. A method was developed and tested for the collection and analysis of ILRs from burnt porcine remains contained within a body bag using dynamic headspace sampling (using an Easy-VOC™ hand-held manually operated grab-sampler and stainless steel sorbent tubes containing Tenax TA) followed by thermal desorption comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (TD-GC×GC-TOFMS). The results demonstrated that a body bag containing remains burnt with gasoline tested positive for the presence of gasoline, while blank body bag controls and a body bag containing remains burnt without gasoline tested negative. The proposed method permits the collection of headspace samples from burnt remains before the remains are removed from the crime scene, limiting the potential for contamination and the loss of volatiles during transit and storage.

Stable Isotopes Analysis of Precipitation in Subtropical Plateau of Yunnan

2014 ◽  
Vol 1010-1012 ◽  
pp. 1059-1063
Author(s):  
Wei Guan ◽  
Tao Fan ◽  
Xiu Qin Zhu
Keyword(s):  
Stable Isotopes ◽  
Rainy Season ◽  
Mean Value ◽  
Dry Season ◽  
Precipitation Line ◽  
Stable Isotopic ◽  
Different Seasons ◽  
Geographical Position ◽  
The Mean ◽  
The Relationship

To elucidate the relationship between stable isotopes of precipitation (SIP) and the extreme drought in Kunming area, based on the stable isotopes data of the GNIP in Kunming site from 1986 to 2003, the precipitation line equation is brought forward and the seasonal change rule of stable isotopes are discussed. The stable isotopic compositions of precipitation exhibit great diversities in different seasons during to influences of multiple factors, such as monsoon, rainfall amount moisture source and others. The δ18O values in rainwater exhibit significant seasonal variations, the average of-10.12‰ in rainy season, the dry season is-4.5‰, having lower values in the rainy season and higher one in the dry season. The amount effect of precipitation is very distinct, that concealed the temperature effect. Got the special geographical position,dvalues present unique characteristics, the average ofdvalues is 10.78‰ in rainy season, and is 4.86‰ in dry season, the mean value is generally lower than most parts of the world.

scholarly journals Temperature Dependent Seed Germination of Dalbergia nigra Allem (Leguminosae)

2001 ◽  
Vol 44 (4) ◽  
pp. 401-404 ◽  
Author(s):  
Fernanda G. A. Ferraz-Grande ◽  
Massanori Takaki
Keyword(s):  
Seed Germination ◽  
Endangered Species ◽  
High Temperatures ◽  
Broad Temperature Range ◽  
Optimum Temperature ◽  
Temperature Dependent ◽  
Temperature Range ◽  
Dalbergia Nigra ◽  
The Mean ◽  
Kinetics Of

The germination of endangered species Dalbergia nigra was studied and 30.5° C was found as optimum temperature, although the species presented a broad temperature range where germination occurs and light had no effect. The analysis of kinetics of seed germination confirmed the asynchronized germination below and above the optimum temperature. The light insensitive seed and germination also at high temperatures indicated that D. nigra could occur both in understories and gaps where the mean temperature was high.

scholarly journals Observations on the Fat Globules in Milk

1913 ◽  
Vol 5 (3) ◽  
pp. 331-356 ◽  
Author(s):  
W. F Cooper ◽  
W. H Nuttall ◽  
G. A Freak
Keyword(s):  
Annual Report ◽  
The Other ◽  
Optimum Temperature ◽  
Fat Globules ◽  
Chief Factors ◽  
Mean Size ◽  
The Subject ◽  
The Mean ◽  
Definite Result

Results of our previous work were published in the Journ. of Agric. Sri., IV, 1911. There, also, a brief summary of the chief papers published on the subject of the fat globules was given, to which it is unnecessary to refer in detail here.When the work was first commenced in 1909, the problem before us was the consideration of the variation in the size of the fat globules, with relation to churning, as regards the different breeds of cattle. The breed was considered because it was usually supposed that this was one of the chief factors which influenced churning. The most definite result of our work was that it was shown that consideration must be given to the character of the milk, irrespective of the breed. This conclusion is quite contrary to that of other workers, but an examination of their figures shows, undoubtedly, that this is actually the case: the results given by Woll (Digestion Expts., Seventh Annual Report, Agric. Expt. Stat, Wisconsin, 1890, 238; also Agric. Sci., 1892, vi, 445) emphasise this point particularly. It is also shown by this year's work, as may be seen from Tables V–XI.The comparative size of the globules has been worked out very thoroughly by Gutzeit, who measured the mean volume of the globule. Other workers give their results as “relative sizes.” In our work we attempted to ascertain the distribution of the fat in the globules, and to this end the number of globules of each size was determined, and curves were drawn. The result of this, however, was negative. At that time we were considering the breeds of the cows from which the milks were obtained; had we considered them solely as milks of a certain mean size of globule, much more might have been achieved.An apparatus was devised to give an absolute figure for the churnability of any cream, but, until the effect of the other factors has been determined, it is impossible to interpret the results. Some experiments to ascertain the optimum temperature were described also.

Intraspecific and interspecific attraction of threeTomicusbeetle species during the shoot-feeding phase

2015 ◽  
Vol 105 (2) ◽  
pp. 225-233 ◽  
Author(s):  
J. Wang ◽  
Z. Zhang ◽  
X. Kong ◽  
H. Wang ◽  
S. Zhang
Keyword(s):  
Sampling Method ◽  
Beetle Species ◽  
Dynamic Headspace ◽  
Headspace Volatiles ◽  
Interspecific Attraction ◽  
Host Trees ◽  
Pinus Yunnanensis ◽  
Dynamic Headspace Sampling ◽  
Ecological Relationship ◽  
Tomicus Minor

AbstractThe shoot beetlesTomicus minor, Tomicus yunnanensis, andTomicus brevipilosushave been decimatingPinus yunnanensistrees for more than 30 years in Southwestern China. To understand the chemical ecological relationship between pines andTomicus, and among the three beetle species, we compared the attraction of these beetles to damaged shoots, extracts from damaged shoots, and volatiles from damaged shoots collected by the dynamic headspace sampling method. Experiments were performed using a modified open-arena olfactometer. The maleT. minorand both sexes ofT. brevipilosuswere more strongly attracted to damaged shoots than to undamaged shoots and they showed attraction to shoots damaged by the same species. FemaleT. minorand both sexes ofT. yunnanensiswere attracted to shoots damaged by femaleT. brevipilosus. The three beetle species were attracted to shoot extracts and dynamic headspace volatiles from shoots damaged by the same species and sex. FemaleT. minorand maleT. yunnanensiswere also attracted to dynamic headspace volatiles from shoots damaged by both sexes ofT. brevipilosus. The results suggested that specific semiochemicals that are induced or produced byT. brevipilosusalso attractT. minorandT. yunnanensis. The semiochemicals in damaged shoots affect the attraction of the three beetle species and play an important chemical communication role in weakening the host trees during the beetles’ shoot-feeding phase.

Analysis of Furaneol in Tomato Using Dynamic Headspace Sampling with Sodium Sulfate

2001 ◽  
Vol 49 (9) ◽  
pp. 4349-4351 ◽  
Author(s):  
Ron G. Buttery ◽  
Gary R. Takeoka ◽  
Michael Naim ◽  
Haim Rabinowitch ◽  
Youngla Nam
Keyword(s):  
Sodium Sulfate ◽  
Headspace Sampling ◽  
Dynamic Headspace ◽  
Dynamic Headspace Sampling
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