Search results for "plant"
showing 10 items of 11944 documents
Preliminary study on analysis and removal of wax from a Carrara marble statue
2015
This preliminary study has mainly focused on the wax identification by nuclear magnetic resonance (NMR) and removal. Wax is used for many purposes in the field of art as protective coatings on wooden, stone or metal objects. From the comparison of the spectra H NMR and in particular with the correspondence of the resonance peaks of the samples taken from the statue and beeswax and paraffin, we can conclude that the wax applied on the statue surface is beeswax. From our data, it can be concluded that, to remove the beeswax, from any stone support, the more effective solvent is the mixture of cyclohexane/ethyl acetate. The removal percentages ranged from 19 to 99%. Lower percentages of remova…
Effect of high temperature annealing (T > 1650 °C) on the morphological and electrical properties of p-type implanted 4H-SiC layers
2019
This work reports on the effect of high temperature annealing on the electrical properties of p-type implanted 4H-SiC. Ion implantations of Aluminum (Al) at different energies (30-200 keV) were carried out to achieve 300 nm thick acceptor box profiles with a concentration of about 10(20) at/cm(3). The implanted samples were annealed at high temperatures (1675-1825 degrees C). Morphological analyses of the annealed samples revealed only a slight increase of the surface roughness RMS up to 1775 degrees C, while this increase becomes more significant at 1825 degrees C (RMS = 1.2 nm). Room temperature Hall measurements resulted in a hole concentration in the range 0.65-1.34 x 10(18)/cm(3) and m…
Construction and expression of a dual vector for chemo-enzymatic synthesis of plant indole alkaloids inEscherichia coli
2010
A dual vector (pQE-70-STR1-SG) containing coding regions of strictosidine synthase (STR1, EC 4.3.3.2) and strictosidine glucosidase (SG, EC 3.2.1.105) from the Indian medicinal plant Rauvolfia serpentina was constructed. Functional expression of the vector in Escherichia coli cells (M15 strain) was proven by isolation of prepurified enzyme extracts, which show both STR1 and SG activities. Incubation of the enzyme in the presence of tryptamine and secologanin delivered the indole alkaloid cathenamine, demonstrating functional co-expression of both STR1- and SG-cDNAs. Cathenamine reduction by sodium borohydride leading to tetrahydroalstonine revealed the chemo-enzymatic indole alkaloid synthe…
Nutrient removal by rice–wheat cropping system as influenced by crop establishment techniques and fertilization options in conjunction with microbial…
2020
AbstractNutrient uptake by the rice–wheat cropping system (RWCS) is an important indicator of soil fertility and plant nutrient status. The hypothesis of this investigation was that the rate and sources of nutrient application can differentially influence nutrient removal and soil nutrient status in different crop establishment techniques (CETs). Cropping system yield was on par in all the CETs evaluated, however, there were significant changes in soil nutrient availability and microbiological aspects. The system nitrogen (N), phosphorus (P), potassium (K) and zinc (Zn) uptake in aerobic rice system followed by zero tillage wheat (ARS-ZTW) was 15.7–17.6 kg ha−1, 0.7–0.9 kg ha−1, 7–9.8 kg ha…
Melatonin and phytomelatonin: Chemistry, biosynthesis, metabolism, distribution and bioactivity in plants and animals—an overview
2021
Melatonin is a ubiquitous indolamine, largely investigated for its key role in the regulation of several physiological processes in both animals and plants. In the last century, it was reported that this molecule may be produced in high concentrations by several species belonging to the plant kingdom and stored in specialized tissues. In this review, the main information related to the chemistry of melatonin and its metabolism has been summarized. Furthermore, the biosynthetic pathway characteristics of animal and plant cells have been compared, and the main differences between the two systems highlighted. Additionally, in order to investigate the distribution of this indolamine in the plan…
Differential toxicity of simazine and diuron to Torilis arvensis and Lolium rigidum
1990
Summary: In a soil application, Torilis arvensis was nearly as susceptible as Lolium rigidum to simazine but was 18-fold more tolerant to diuron. Treat ment with diuron inhibited photosynthesis in L. rigidum but had only a limited effect in T. arvensis although chloroplasts isolated from both species displayed similar susceptibility. 14C-diuron degradation in plants was limited, with the formation of conjugates of mono-methyl-diuron in T. arvensis and N-dealkylated derivatives of diuron in L. rigidum. 14C-diuron entered the roots and was translocated throughout the leaves of L. rigidum but was restricted to stems, leaf petioles and leaf veins of T. arvensis. This difference in transport pat…
Guillain-Barré syndrome after orthotopic liver transplantation: A clinical manifestation of immune reconstitution inflammatory syndrome?
2018
Guillain-Barrè Syndrome, as part of the spectrum of dysimmune neuropathies, is unexpected to occur in immunocompromised hosts. We describe a clinical case of Guillain-Barrè syndrome, occurred a few weeks after a liver transplant, and we postulate that our case would satisfy all requirements to explain this peripheral nervous system complication as a clinical manifestation of an Immune reconstitution inflammatory syndrome. In this setting of liver transplantation, complicated by potentially multiple infective triggers, reduction of immunosuppression and reversal of pathogen-induced immunosuppression, through antimicrobial therapy, may have led to pro-inflammatory response. The pro-inflammato…
Allium albanicum (Amaryllidaceae), a new species from Balkans and its relationships with A. meteoricum Heldr. & Hausskn. ex Halácsy
2019
A new species, Alliumalbanicum, is described and illustrated from Albania (Balkan Peninsula). It grows on serpentines or limestone in open rocky stands with a scattered distribution, mainly in mountain locations. Previously, the populations of this geophyte were attributed to A.meteoricum Heldr. & Hausskn. ex Halácsy, described from a few localities of North and Central Greece. These two species indeed show close relationships, chiefly regarding some features of the spathe valves, inflorescence and floral parts. They also share the same diploid chromosome number 2n =16 and similar karyotype, while seed testa micro-sculptures and leaf anatomy reveal remarkable differences. There are …
Hemodynamic and ventilatory changes during implant surgery with intravenous conscious sedation
2010
Purpose: This study was conducted to determine the hemodynamic and ventilatory changes during implant surgery with intravenous conscious sedation, and whether preoperative anxiety, gender or age influence these parameters. Patients and Methods: A prospective study carried out between May 2004 and February 2007, on 102 patients treated with dental implants under local anesthesia and conscious intravenous sedation. Patients completed a questionnaire prior to surgery to evaluate preoperative dental anxiety using Corah's scale. The hemodynamic and ventilatory changes were evaluated by monitoring systolic pressure (SP), diastolic pressure (DP), heart rate (HR) and oxygen saturation (SaO2). These…
Diversity and Evolution of the Phenazine Biosynthesis Pathway
2010
ABSTRACT Phenazines are versatile secondary metabolites of bacterial origin that function in biological control of plant pathogens and contribute to the ecological fitness and pathogenicity of the producing strains. In this study, we employed a collection of 94 strains having various geographic, environmental, and clinical origins to study the distribution and evolution of phenazine genes in members of the genera Pseudomonas , Burkholderia , Pectobacterium , Brevibacterium , and Streptomyces . Our results confirmed the diversity of phenazine producers and revealed that most of them appear to be soil-dwelling and/or plant-associated species. Genome analyses and comparisons of phylogenies inf…