Gas–liquid chromatography of terpenes. Part XVII. The volatile oil of the leaves of Juniperus virginiana L.

1968 ◽  
Vol 46 (23) ◽  
pp. 3743-3750 ◽  
Author(s):  
A.R. Vinutha ◽  
E. Von Rudloff

The leaf oil of the red juniper was found to contain mainly sabinene, as well as limonene, α-pinene, γ-terpinene, terpinolene, 3-carene, myrcene, 4-terpinenol, citronellol, elemol, γ-, α-, and β-eudesmol, the aromatic ethers estragole, safrole, methyl eugenol, and elemicin. Another aromatic ether, methyl vinyl anisole, was isolated which has not been found previously in essential oils. The acetates 1 and 2 obtained previously in two related juniper leaf oils were present and the first has been identified as elemol acetate. Small amounts of α-thujene, p-cymene, linalool, and δ-cadinene were also identified.Quantitative aspects were studied with a view of future chemosystematic investigations. The error in duplicate runs was 0.1% for well-resolved peaks, but the absolute error, as determined by use of internal standards, was larger. Leaf oils of different trees from Texas and Ontario were found to give wide quantitative variations of the individual components.

1968 ◽  
Vol 46 (5) ◽  
pp. 679-683 ◽  
Author(s):  
E. Von Rudloff

The major components of the leaf oil of the Ashe juniper were found to be d-camphor (42.1 %), d-bornyl acetate (22.5%), d-limonene (8.4%), tricyclene (4.8%), d-camphene (4.4%), d-borneol (2.9%), p-cymene (2.8%), d-α-myrcene (1.8%), d-α-pinene (1.7%), and d-camphene hydrate (1.5%). This appears to be the first time that the latter alcohol has been isolated from a natural source. Smaller amounts of linalool, carvone, elemol, and traces of trans-2-methyl-6-methylene-3,7-octadien-2-ol were also identified. Several alcohols having terminal methylene groups were isolated in trace amounts.The monoterpenes found in this oil are not typical for the genus Juniperus and this result offers a unique chemical approach to the study of introgression of the Ashe juniper with other juniper species.


1983 ◽  
Vol 50 (3) ◽  
pp. 321-329 ◽  
Author(s):  
Eric C. Needs ◽  
Graeme D. Ford ◽  
A. Jane Owen ◽  
Brian Tuckley ◽  
Malcolm Anderson

SummaryA quantitative method for rapid routine analysis of individual free fatty acids (FFA) in milk was developed. Lipid was extracted from milk in ether and FFA were recovered by shaking the extract with anion exchange resin Amberlyst 26. The resin-bound FFA were methylated directly and the individual acids quantified, using internal standards, by gas-liquid chromatography. The properties of the resin were measured. The validity of the method was established by extraction of FFA mixtures and milk. Individual acids were, on average, found to be within 6% of the actual concentration present in the mixture. An average coefficient of variation of 4·3% was achieved for the major individual fatty acids on repeated extraction of a single milk sample.


1969 ◽  
Vol 47 (11) ◽  
pp. 2081-2086 ◽  
Author(s):  
E. von Rudloff ◽  
V. K. Sood

The volatile leaf oil of the local common juniper was found to consist mainly of α-pinene (73 to 83%) and smaller amounts (0.5 to 5%) of β-pinene, 3-carene, myrcene, limonene, methyl citronellate, bornyl acetate, myrtenal, myrtenol, myrtenyl acetate, α-terpineol, citronellol, citronellyl acetate, nerolidol, farnesol, and an unusual hydroxy ketone. Of the many trace constituents, β-phellandrene, citronellal, "iso-" citronellal, linalool, geraniol, isopulegol, 4-terpinenol, and ε-cadinene were isolated, whereas camphene, sabinene, α-phellandrene, γ-terpinene, terpinolene, p-cymene, fenchone, thujone, isothujone and δ-cadinene could only be tentatively identified.There was little variation in the quantitative composition of the leaf oil from one plant to another. Since the composition of this oil differs significantly from that of other juniper leaf oils, chemotaxonomic studies by means of leaf oil analysis are feasible.


1964 ◽  
Vol 42 (8) ◽  
pp. 1890-1895 ◽  
Author(s):  
E. von Rudloff ◽  
F. M. Couchman

The neutral leaf oil of Rocky Mountain juniper was analyzed by gas–liquid chromatography. d-Sabinene was found to be the major constituent (45.7%) and smaller amounts of d-limonene (11.4%), d-α-pinene (4.2%), γ-terpinene (1.15%), p-cymene (1.4%), l-linalool (1.2%), d-terpinen-4-ol (2.9%), citronellol (0.2%),l-β-elemene (0.2–0.3%), three isomeric cadinenes (2.7%), l-elemol (6.0%), and safrole (1.85%) were isolated. α-Thujene, camphene, car-3-ene, myrcene, α-terpinene, terpinolene, thujone, isothujone, methyl citronellate, sabinyl acetate, sabinol, geraniol, α- and δ-cadinol, and trans-isoeugenol were tentatively identified. An unidentified acetate (II) (4.7%) was isolated from the oxygenated sesquiterpene fraction and another appears to be present in trace amounts.The composition of the oils from the leaves of four local ornamental plants was found to differ significantly from that of the wild juniper.


1965 ◽  
Vol 43 (5) ◽  
pp. 1017-1021 ◽  
Author(s):  
F. M. Couchman ◽  
E. Von Rudloff

The neutral leaf oil of the creeping juniper from the Prairies was analyzed by gas–liquid chromatography. d-Sabinene (36.5%) was found to be the major constituent, and smaller amounts of d-limonene (17.5%), p-cymene (3.0%), d-α-pinene (1.6%), γ-terpinene (0.4%), d-terpinen-4-ol (4.6%), linalool (0.8%), citronellol (0.8%), γ-cadinene (1.3%), l-elemol (3.8%), α-cadinol or γ-eudesmol (1.6%), and impure α-cyperone (3.9%) were isolated. α-Thujene (3.0%), camphene (0.2%), β-pinene (0.3%), myrcene (3.0%),β-phellandrene (0.2%,), terpinolene (0.1%), 2,4-(8)-p-menthadiene (0.1%), methyl citronellate (0.4%), and geraniol (0.2%) were tentatively identified. The composition of this oil closely resembles that of Rocky Mountain juniper leaves. A small amount of the oil from a hybrid of these two species was analyzed and the possibility of detecting hybridization by analysis of the leaf oil is discussed.


2018 ◽  
Vol 12 (02) ◽  
pp. 155-165
Author(s):  
Holger Hendrix ◽  
Vladimir Kamlak ◽  
Georgi Prisadov ◽  
Katrin Welcker

The treatment of pain after thoracic surgery is a challenge and takes place in the individual clinics mostly according to clinic internal standards. It exists no currently valid S3 guideline for the treatment of acute perioperative and posttraumatic pain. For an effective pain treatment as well individual pain experience as the pain intensity of the various thoracic surgical procedures must be considered. Regular pain assessment with appropriate methods and their documentation form the basis for adequate and adapted pain therapy.There are a number of different pain therapy methods, non-medicamentous and drug-based methods, whose effectiveness is described in the literature partially different. For the treatment of acute postoperative pain after thoracic surgery, mainly drug-related procedures are used, except for physiotherapy as a non-medicamentous method. Increasingly, alternative procedures for the peridural catheter as a therapeutic gold standard in the treatment of pain after thoracic surgery are used. Their application can be integrated into a therapeutic algorithm.


1972 ◽  
Vol 55 (4) ◽  
pp. 840-845 ◽  
Author(s):  
Charles R Midkiff ◽  
Willard D Washington

Techniques developed for use with gas-liquid chromatography for the examination of evidence collected at the scene of suspected arson fires and firebombings are discussed. Both solvent extraction and vapor phase examinations are employed. Internal standards are used for the identification of specific components in actual samples to allow confirmation of hydrocarbon type, e.g., gasoline and kerosene. Operating parameters and solvent selection criteria are included. Results obtained from known materials and residual hydrocarbons in actual samples are compared.


2010 ◽  
Vol 138 (12) ◽  
pp. 4402-4415 ◽  
Author(s):  
Paul J. Roebber

Abstract Simulated evolution is used to generate consensus forecasts of next-day minimum temperature for a site in Ohio. The evolved forecast algorithm logic is interpretable in terms of physics that might be accounted for by experienced forecasters, but the logic of the individual algorithms that form the consensus is unique. As a result, evolved program consensus forecasts produce substantial increases in forecast accuracy relative to forecast benchmarks such as model output statistics (MOS) and those from the National Weather Service (NWS). The best consensus produces a mean absolute error (MAE) of 2.98°F on an independent test dataset, representing a 27% improvement relative to MOS. These results translate to potential annual cost savings for electricity production in the state of Ohio of the order of $2 million relative to the NWS forecasts. Perfect forecasts provide nearly $6 million in additional annual electricity production cost savings relative to the evolved program consensus. The frequency of outlier events (forecast busts) falls from 24% using NWS to 16% using the evolved program consensus. Information on when busts are most likely can be provided through a logistic regression equation with two variables: forecast wind speed and the deviation of the NWS minimum temperature forecast from persistence. A forecast of a bust is 4 times more likely to be correct than wrong, suggesting some utility in anticipating the most egregious forecast errors. Discussion concerning the probabilistic applications of evolved programs, the application of this technique to other forecast problems, and the relevance of these findings to the future role of human forecasting is provided.


2020 ◽  
Author(s):  
Peter C. Reinacher ◽  
Thomas E. Schlaepfer ◽  
Martin A. Schick ◽  
Jürgen Beck ◽  
Hartmut Bürkle ◽  
...  

AbstractA potential shortage of intensive care ventilators has led to the idea to ventilate more than one patient with a single ventilator. Besides other problems, this is associated with the lack of knowledge concerning distribution of tidal volume and the patients’ individual respiratory system mechanics.In this study we used two simple hand-manufactured adaptors to connect physical models of two adult respiratory systems to one ventilator. The artificial lungs were ventilated in the pressure-controlled mode and we investigated if disconnecting one lung from the ventilation circuit for several breaths would allow to determine reliably the other lung’s tidal volume and compliance.Compliances and volumes were measured both with the ventilator and external sensors corresponded well. However, tidal volumes measured via the ventilator were smaller compared to the tidal volumes measured via the external sensors with an absolute error of 5.3 ± 2.5%. The tidal volumes of the individual artificial lungs were distributed in proportion to the compliances and did not differ relevantly when both artificial lungs were connected to when one was disconnected.We conclude that in case of emergency, ventilation of two patients with one ventilator requires two simple hand-crafted tubes as adaptors and available standard breathing circuit components. In such a setting, respiratory system mechanics and tidal volume of each individual patient can be reliably measured during short term clamping of the tracheal tube of the respective other patient.


PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0246071
Author(s):  
Yen-Fen Ko ◽  
Kuo-Sheng Cheng

Electrical impedance tomography (EIT) is widely used for bedside monitoring of lung ventilation status. Its goal is to reflect the internal conductivity changes and estimate the electrical properties of the tissues in the thorax. However, poor spatial resolution affects EIT image reconstruction to the extent that the heart and lung-related impedance images are barely distinguishable. Several studies have attempted to tackle this problem, and approaches based on decomposition of EIT images using linear transformations have been developed, and recently, U-Net has become a prominent architecture for semantic segmentation. In this paper, we propose a novel semi-Siamese U-Net specifically tailored for EIT application. It is based on the state-of-the-art U-Net, whose structure is modified and extended, forming shared encoder with parallel decoders and has multi-task weighted losses added to adapt to the individual separation tasks. The trained semi-Siamese U-Net model was evaluated with a test dataset, and the results were compared with those of the classical U-Net in terms of Dice similarity coefficient and mean absolute error. Results showed that compared with the classical U-Net, semi-Siamese U-Net exhibited performance improvements of 11.37% and 3.2% in Dice similarity coefficient, and 3.16% and 5.54% in mean absolute error, in terms of heart and lung-impedance image separation, respectively.


Sign in / Sign up

Export Citation Format

Share Document