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Gas chromatography (GC) techniques for analyzing and determining the cannabinoid profile in cannabis (Cannabis sativa L.) are widely used in standard laboratories; however, these methods may mislabel the profile when used under rapid conditions. Our study aimed to highlight this problem and optimize GC column conditions and mass spectrometry (MS) parameters to accurately identify cannabinoids in both standards and forensic samples. The method was validated for linearity, selectivity, and precision. It was observed that when tetrahydrocannabinol (Δ9-THC) and cannabidiolic acid (CBD-A) were examined using rapid GC conditions, the resulting derivatives generated identical retention times. Wider chromatographic conditions were applied. The linear range for each compound ranged from 0.02 μg/mL to 37.50 μg/mL. The R2 values ranged from 0.996 to 0.999. The LOQ values ranged from 0.33 μg/mL to 5.83 μg/mL, and the LOD values ranged from 0.11 μg/mL to 1.92 μg/mL. The precision values ranged from 0.20% to 8.10% RSD. In addition, forensic samples were analyzed using liquid chromatography (HPLC-DAD) in an interlaboratory comparison test, with higher CBD and THC content than GC–MS determination (p < 0.05) in samples. Overall, this study highlights the importance of optimizing GC techniques to avoid mislabeling cannabinoids in cannabis samples. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Glass frits with a P2O5/K2O ratio equal to 0.65 and different concentrations of SiO2 (6.5–56.0 wt%), CaO (0–5.1 wt%) and Al2O3 (0–14.6 wt%) have been prepared and analysed as potential glass fertilizers (GF). RESULTS: P2O5 and K2O were leached primarily within the first 5 days but the total amount was dependent on the SiO2/Al2O3 ratio of the glass frit. Sustained P2O5 and K2O leaching for more than 40 days could be obtained if the glass frit contained more than 7% Al2O3. A final glass frit composition (29% SiO2, 5% CaO, 7% Al2O3, 30% P2O5, 25% K2O) was selected and used in an experimental tomato crop of 1 ha area, where one half was fertilized with an NPK conventional fertilizer and the other half with the GF fertilizer. CONCLUSION: After harvesting the tomato crops, the GF fertilizer was found to result in a higher yield than the NPK conventional fertilizer: 59980 kg and 74 360 kg for NKP and GF, respectively. The general characteristics of the harvested tomato fruits and leaves were similar in the two cases and the differences fell within statistical error. No differences in any of the soil characteristics were detected as a result of the use of GF. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The lichen Circinaria gyrosa is an astrobiological model defined by its high capacity of resistance to space conditions and to a simulated martian environment. Therefore, it became part of the currently operated BIOMEX experiment on board the International Space Station and the recent STARLIFE campaign to study the effects of four types of space-relevant ionizing radiation. The samples were irradiated with helium and iron ions at doses up to 2 kGy, with X-rays at doses up to 5 kGy and with γ rays at doses from 6 to 113 kGy. Results on C. gyrosa's resistance to simulated space ionizing radiation and its post-irradiation viability were obtained by (i) chlorophyll a fluorescence of photosystem II (PSII), (ii) epifluorescence microscopy, (iii) confocal laser scanning microscopy (CLSM), and (iv) field emission scanning electron microscopy (FESEM). Results of photosynthetic activity and epifluorescence show no significant changes up to a dose of 1 kGy (helium ions), 2 kGy (iron ions), 5 kGy (X-rays)-the maximum doses applied for those radiation qualities-as well as a dose of 6 kGy of γ irradiation, which was the lowest dose applied for this low linear energy transfer (LET) radiation. Significant damage in a dose-related manner was observed only at much higher doses of γ irradiation (up to 113 kGy). These data corroborate the findings of the parallel STARLIFE studies on the effects of ionizing radiation on the lichen Circinaria gyrosa, its isolated photobiont, and the lichen Xanthoria elegans. Key Words: Simulated space ionizing radiation-Gamma rays-Extremotolerance-Lichens- Circinaria gyrosa-Photosynthetic activity. Astrobiology 17, 145-153. [ABSTRACT FROM AUTHOR]

Objective Our study aims were to establish whether subjects enrolled in current obstetric clinical trials proportionately reflects the contemporary representation of Hispanic ethnicities and their birth rates in the United States. Methods Using comprehensive source data over a defined interval (January 2011-September 2015) on birth rates by ethnicity from the Centers for Disease Control and Prevention (CDC), we evaluated the proportional rate by ethnicity, then analyzed the observed to expected relative ratio of enrolled subjects. Results Hispanic women comprise a significant contribution to births in the United States (23% of all births). Systematic analysis of 90 published obstetric clinical trials showed a correlation between inclusion of Hispanic gravidae and the corresponding state's birth rates (r = 0.501, p < 0.001). While the mean was strongly correlated, individual clinical trials may have relatively over-enrolled (n = 31, or 34%) or underenrolled (n = 33, or 37%) relative to their regional population. In 48% of obstetric clinical trials the Hispanic proportion of the study population was not reported. Conclusion Hispanic gravidae represent a significant number of contemporary U.S. births, and are generally adequately represented as obstetric subjects in clinical trials. However, this is trial-dependent, with significant trial-specific under- and over-enrollment of Hispanic subjects relative to the regional birth population. document was downloaded for personal use only. Unauthorized distribution is strictly [ABSTRACT FROM AUTHOR]

Cryptoendolithic microbial communities and epilithic lichens have been considered as appropriate candidates for the scenario of lithopanspermia, which proposes a natural interplanetary exchange of organisms by means of rocks that have been impact ejected from their planet of origin. So far, the hardiness of these terrestrial organisms in the severe and hostile conditions of space has not been tested over extended periods of time. A first long-term (1.5 years) exposure experiment in space was performed with a variety of rock-colonizing eukaryotic organisms at the International Space Station on board the European EXPOSE-E facility. Organisms were selected that are especially adapted to cope with the environmental extremes of their natural habitats. It was found that some-but not all-of those most robust microbial communities from extremely hostile regions on Earth are also partially resistant to the even more hostile environment of outer space, including high vacuum, temperature fluctuation, the full spectrum of extraterrestrial solar electromagnetic radiation, and cosmic ionizing radiation. Although the reported experimental period of 1.5 years in space is not comparable with the time spans of thousands or millions of years believed to be required for lithopanspermia, our data provide first evidence of the differential hardiness of cryptoendolithic communities in space. Key Words: Astrobiology-Lithopanspermia-Radiation resistance-Survival-Vacuum. Astrobiology 12, 508-516. [ABSTRACT FROM AUTHOR]

Abstract: In the space experiments Lithopanspermia, experimental support was provided to the likelihood of the lithopanspermia concept that considers a viable transport of microorganisms between the terrestrial planets by means of meteorites. The rock colonising lichens Rhizocarpon geographicum and Xanthoria elegans, the vagrant lichen Aspicilia fruticulosa, and endolithic and endoevaporitic communities of cyanobacteria and bacteria with their natural rock substrate were exposed to space for 10days onboard the Biopan facility of the European Space Agency (ESA). Biopan was closed during launch and re-entry. In addition, in the Stone facility, one sample of R. geographicum on its natural granitic substrate was attached at the outer surface of the re-entry capsule close to the stagnation point, only protected by a thin cover of glass textolite. Post-flight analysis, which included determination of the photosynthetic activity, LIVE/DEAD staining, and germination capacity of the ascospores, demonstrated that all three lichen were quite resistant to outer space conditions, which include the full spectrum of solar extraterrestrial electromagnetic radiation or selected wavelength ranges. This high resistance of the lichens to space appears to be due to their symbiotic nature and protection by their upper pigmented layer, the cortex. In contrast, the rock- or halite-inhabiting bacteria were severely damaged by the same exposure. After atmospheric re-entry, the granite of the Stone sample was transformed into a glassy, nearly homogenous material, with several friction striae. None of the lichen cells survived this re-entry process. The data suggest that lichens are suitable candidates for testing the concept of lithopanspermia, because they are extremely resistant to the harsh environment of outer space. The more critical event is the atmospheric re-entry after being captured by a planet. Experiments simulating the re-entry process of a microbe-carrying meteoroid did not show any survivors. [Copyright &y& Elsevier]

Many cyanobacteria are known to tolerate environmental extremes. Motivated by an interest in selecting cyanobacteria for applications in space, we launched rocks from a limestone cliff in Beer, Devon, United Kingdom, containing an epilithic and endolithic rock-dwelling community of cyanobacteria into low Earth orbit (LEO) at a height of approximately 300 kilometers. The community was exposed for 10 days to isolate cyanobacteria that can survive exposure to the extreme radiation and desiccating conditions associated with space. Culture-independent (16S rRNA) and culture-dependent methods showed that the cyanobacterial community was composed of Pleurocapsales, Oscillatoriales, and Chroococcales. A single cyanobacterium, a previously uncharacterized extremophile, was isolated after exposure to LEO. We were able to isolate the cyanobacterium from the limestone cliff after exposing the rock-dwelling community to desiccation and vacuum (0.7 x 10-3 kPa) in the laboratory. The ability of the organism to survive the conditions in space may be linked to the formation of dense colonies. These experiments show how extreme environmental conditions, including space, can be used to select for novel microorganisms. Furthermore, it improves our knowledge of environmental tolerances of extremophilic rock-dwelling cyanobacteria. [ABSTRACT FROM AUTHOR]

Abstract: Many lichen species are regarded as extremophiles in terms of temperature, radiation and desiccation survival. Therefore, lichens have been previously proposed, together with unicellular algae and bacteria, as the living system most likely to resist the extreme conditions of outer space. This enables, following the “Panspermia” theory, speculation about the possibility of life transfer between Earth and other planets. Different experiments have been designed to establish the survival capability of these organisms exposed to space conditions. In particular, the damaging effect of solar UV was studied under various protecting conditions. Different lichen species were exposed to space in the BIOPAN-5 and BIOPAN-6 facilities of the European Space Agency located at the outer shell of the Russian Earth orbiting FOTON M2 satellite. Chlorophyll fluorescence and gas exchange systems were used for the measurement of photosynthetic parameters. All exposed lichens, independently of the filters used, showed after the flight nearly the same photosynthetic activity as measured before the flight. These findings suggest that lichens could stay alive in space even completely exposed to massive UV and cosmic radiation, which have been proved being lethal for bacteria and other microorganisms. Improvements and possible upgrading of the existing experiment designs are also explored in view of a future and more intensive use of lichens in Astrobiology. [Copyright &y& Elsevier]