Search results for "Reaction"
showing 10 items of 6134 documents
Characterisation of phenotypic plasticity in seedling stage of native and invasive populations in Ambrosia artemisiifolia L.
2012
Increased phenotypic plasticity has often been invoked as an hypothesis to explain the capacity of alien invasive plant species to colonize new environments, because it may enhance the ability of plants to cope with new biotic and abiotic conditions. Following this hypothesis, alien invasive populations should be represented by more plastic genotypes than populations in the native range. In annual species, the seedling stage is of crucial importance for population dynamics but surprisingly very few studies have investigated differences in phenotypic plasticity on seedling traits. Based on populations from the native range (North America) and the invasive range (France) of Ambrosia artemisii…
High-throughput sequencing of amplicons for monitoring yeast biodiversity in must and during alcoholic fermentation
2014
Abstract We compared pyrosequencing technology with the PCR-ITS-RFLP analysis of yeast isolates and denaturing gradient gel electrophoresis (DGGE). These methods gave divergent findings for the yeast population. DGGE was unsuitable for the quantification of biodiversity and its use for species detection was limited by the initial abundance of each species. The isolates identified by PCR-ITS-RFLP were not fully representative of the true population. For population dynamics, high-throughput sequencing technology yielded results differing in some respects from those obtained with other approaches. This study demonstrates that 454 pyrosequencing of amplicons is more relevant than other methods …
Impact of a new bio-pesticide produced by Paenibacillus sp. strain B2 on the genetic structure and density of soil bacterial communities
2007
The effect of paenimyxin, a new biopesticide produced by Paenibacillus sp. strain B2, on the density of soil bacterial communities was assessed by colony counting and by 16S rDNA and nirK quantitative polymerase chain reaction (PCR). Paenimyxin had a negative effect on the bacterial colony-forming unit (CFU) number, which was significantly reduced 2 and 4 days after treatment. The effect of paenimyxin on cultivatable bacteria was negligible 7 days after treatment. Approximately 107 16S rDNA sequences per gram of soil (dry weight) were detected by quantitative PCR in all samples. Paenimyxin did not affect the quantification of 16S rDNA or of the denitrifying bacterial community. In addition,…
The Largest Subunit of RNA Polymerase II as a New Marker Gene to Study Assemblages of Arbuscular Mycorrhizal Fungi in the Field
2014
Due to the potential of arbuscular mycorrhizal fungi (AMF, Glomeromycota) to improve plant growth and soil quality, the influence of agricultural practice on their diversity continues to be an important research question. Up to now studies of community diversity in AMF have exclusively been based on nuclear ribosomal gene regions, which in AMF show high intra-organism polymorphism, seriously complicating interpretation of these data. We designed specific PCR primers for 454 sequencing of a region of the largest subunit of RNA polymerase II gene, and established a new reference dataset comprising all major AMF lineages. This gene is known to be monomorphic within fungal isolates but shows an…
Combustion wave structure during the MoSi2 synthesis by Mechanically-Activated Self-propagating High-temperature Synthesis (MASHS): In situ time-reso…
2006
Abstract In situ synchrotron time-resolved X-ray diffraction experiments coupled with an infrared imaging camera have been used to reveal the combustion wave structure during the production of MoSi2 by Mechanically Activated Self-propagating High-temperature Synthesis (MASHS). The fast combustion front exhibits a form described as an ‘equilibrium structure’ where the chemical reaction is the sole major driving force. In the MASHS process, oxide-free interfaces between Mo and Si nanocrystallites enhance the reaction Mo+2Si→MoSi2. Exhaustive time-resolved investigations show a possible solid-state process in the first second of the reaction within the combustion front. If preheating is added,…
Temporal-range estimation of multiple objects: evidence for an early bottleneck.
2011
When making parallel time-to-contact (TTC) estimates of two approaching objects, the two respective TTC estimates interfere with one another in an asymmetric fashion. The TTC of the later-arriving object is systematically overestimated, while the estimated TTC for the first-arriving object is as accurate as in a condition presenting only a single object. This asymmetric interference points to a processing bottleneck that could be due to early (e.g., during the estimation of the TTC from the optic flow) or late (e.g., during the timing of the response or the motor execution) constraints in the TTC estimation process. We used a Sperling-like prediction-motion task to differentiate between the…
Photocatalytic oxidation of acetonitrile in gas–solid and liquid–solid regimes
2005
Il programma NON mi ha consentito di scaricare il PDF di questo articolo. Se lo volete ditemi come inviarlo ABSTRACT Photocatalytic degradation of acetonitrile was carried out in both gas–solid and liquid–solid regimes using two commercial TiO2 catalysts (Merck and Degussa P25). For the gas–solid regime, a continuous annular photoreactor was used. The influence on photodegradation kinetics of the gas flow rate and concentrations of acetonitrile, oxygen, and water was investigated. Acetonitrile degradation products detected in the gas phase included carbon dioxide and hydrogen cyanide. The same photoactivity was exhibited in the presence and in the absence of water vapour. The liquid–solid reg…
Comparison of the generation II with IV heterogeneous Ziegler-Natta catalysts used in propylene polymerizations
1998
An unsupported TiCl3-based catalyst (generation II), modified with n-butyl ether and AlEt2Cl3, was compared with a MgCl2/dibutyl phthalate/AlEt3/cyclohexylmethyldimethoxysilane catalyst system (generation IV) in propylene polymerizations. The latter (magnesium-supported) was fund to be more than 20 times as active as the former and more stereospecific, but to yield PP with a lower molecular weight (Table 2). The kinetics of the polymerizations studied with either of the catalyst, and involving the determination of concentrations of active sites [C0*] and elementary reaction rate constants (Table 4) based on earlier kinetic models, showed the C0*-values in the magnesium-supported catalyst to…
THE KEY ROLE OF THE CLINICAL PHARMACIST IN THE MANAGEMENT OF ANTICANCER THERAPIES: A PILOT STUDY IN THE TREATMENT OF PATIENTS WITH NON-SMALL CELL LUN…
2021
Lung cancer accounts for a quarter of all mortality cases worldwide. To date, numerous efforts have been done to identify the best therapeutic approach, especially in the advanced stage of the disease, and to extend the overall survival of patients. Careful surveillance of patients during therapy is essential in order to identify undesirable effects and to evaluate possible adverse reactions in case of coadministration. This study aims to compare two types of anticancer therapy, immunotherapy and chemotherapy, administered to NSCLC patients in the Medical Oncology Unit of the ARNAS “Di Cristina Benfratelli” Civic Hospital in Palermo (Italy), and to highlight the key role of clinical pharmac…
Impact of the coronavirus pandemic on maxillofacial trauma:a retrospective study in southern Spain
2022
The coronavirus pandemic has impacted health systems worldwide, with Spain being one of the most affected countries. However, little is known about the extent to which the effects of staying home, social distancing, and quarantine measures have influenced the epidemiology of patients with maxillofacial trauma. The aim of this study was to analyze the impact of the coronavirus pandemic on the incidence, demographic patterns, and characteristics of maxillofacial fractures in the largest hospital in southern Spain. Data from patients who underwent surgery for maxillofacial fractures during the first year of the pandemic between 16 March 2020 and 14 March 2021 (pandemic group) were retrospectiv…