Search results for "Alteration"
showing 10 items of 76 documents
The role of Mediterranean wetlands in climate regulation and greenhouse gases exchanges: from carbon biogeochemistry to European water and nature Dir…
2022
Atesa la seua alta activitat biogeoquímica, els aiguamolls són un dels tipus d'ecosistemes més actius en el cicle global del carboni, amb altes taxes d'intercanvi de carboni i de gasos d'efecte hivernacle (GEH), i, per tant, un gran potencial de regulació climàtica. Una de les parts més importants de la biogeoquímica del carboni als aiguamolls està lligada a les taxes metabòliques, a partir del coneixement de les quals es pot determinar un balanç de carboni associat amb el potencial intercanvi de carboni amb l'atmosfera. La seua capacitat per retindre carboni i mitigar el canvi climàtic, o, per contra, d'alliberar més GEH, i contribuir a l'escalfament global, es determina pel balanç de carb…
Periodontal disease associated to systemic genetic disorders
2007
A number of systemic disorders increase patient susceptibility to periodontal disease, which moreover evolves more rapidly and more aggressively. The underlying factors are mainly related to alterations in immune, endocrine and connective tissue status. These alterations are associated with different pathologies and syndromes that generate periodontal disease either as a primary manifestation or by aggravating a pre-existing condition attributable to local factors. This is where the role of bacterial plaque is subject to debate. In the presence of qualitative or quantitative cellular immune alterations, periodontal disease may manifest early on a severe localized or generalized basis - in s…
A laboratory cave for the study of wall degradation in rock art caves : an implementation in the Vézère area
2013
The aim of this proposal is to present an original approach to the study and preservation of rock art caves. A multidisciplinary study of cave wall alteration will be performed to understand the impact of environmental context on the evolution of wall surfaces. The approach involves the choice of a cave with characteristics similar to painted caves in the studied area (Vézère Valley in Dordogne, France): e.g., cave wall alteration, lithology, morphology, etc. This selected cave is intended to become a laboratory cave, monitored for the acquisition of chemical, physical and biological environmental data on bedrock, air and fluids along with their characteristics. A cave without art or archae…
TLR4 elimination prevents synaptic and myelin alterations and long-term cognitive dysfunctions in adolescent mice with intermittent ethanol treatment.
2015
The adolescent brain undergoes important dynamic and plastic cell changes, including overproduction of axons and synapses, followed by rapid pruning along with ongoing axon myelination. These developmental changes make the adolescent brain particularly vulnerable to neurotoxic and behavioral effects of alcohol. Although the mechanisms of these effects are largely unknown, we demonstrated that ethanol by activating innate immune receptors toll-like receptor 4 (TLR4), induces neuroinflammation and brain damage in adult mice. The present study aims to evaluate whether intermittent ethanol treatment in adolescence promotes TLR4-dependent pro-inflammatory processes, leading to myelin and synapti…
Six années de suivi du flux d'érosion éolienne sur un sol sableux cultivé au Sahel : Impacts des résidus de culture et de l'encroûtement
2013
In the Sahel, wind erosion occurs particularly in cultivated fields. This work was leaded at Banizoumbou in Niger where wind erosion fluxes have been measured for six years. The aims of this study was i) to monitor crop residues cover on traditional field and to quantify its influence on wind erosion ii) to characterize the impacts of soils crusting on erosion flux, iii) to characterize the impact of herbaceous strips on wind flux. Results showed that crop residues efficiently prevent cultivated fields from wind erosion during the dry season (January to April) and considerably reduce erosion fluxes at the beginning of the rainy season (May to July). Under a minimal crop residues cover rate …
Binding Site Alteration Is Responsible for Field-Isolated Resistance to Bacillus thuringiensis Cry2A Insecticidal Proteins in Two Helicoverpa Species
2010
Background Evolution of resistance by target pests is the main threat to the long-term efficacy of crops expressing Bacillus thuringiensis (Bt) insecticidal proteins. Cry2 proteins play a pivotal role in current Bt spray formulations and transgenic crops and they complement Cry1A proteins because of their different mode of action. Their presence is critical in the control of those lepidopteran species, such as Helicoverpa spp., which are not highly susceptible to Cry1A proteins. In Australia, a transgenic variety of cotton expressing Cry1Ac and Cry2Ab (Bollgard II) comprises at least 80% of the total cotton area. Prior to the widespread adoption of Bollgard II, the frequency of alleles conf…
Body mass index and impact on semen quality of men attending an infertility clinic
2019
Background: The reproductive consequences of lifestyle factors in men are still controversial. In this prospective study, we verified the impact of body mass index alterations on semen parameters of patients who attended an infertility clinic. Materials and Methods: Semen samples from 156 subjects aged 22 to 53 years were analyzed. Smokers were categorized as mild (≤ 10 cigarettes/day), moderate (10-20 cigarettes/day”) and heavy smokers (> 20 cigarettes/day”). Men were grouped based upon calculated body mass index values (underweight, <18.5 Kg/m2; normal, 18.5-24.9 Kg/m2; overweight, 25-29.9 Kg/m2; obese, ≥ 30 Kg/m2). The data collected included patient height and weight, semen volume…
Alteration-Induced Volcano Instability at La Soufrière de Guadeloupe (Eastern Caribbean)
2021
International audience; Volcanoes are unstable structures that deform laterally and frequently experience mass wasting events. Hydrothermal alteration is often invoked as a mechanism that contributes significantly to volcano instability. We present a study that combines laboratory experiments, geophysical data, and large-scale numerical modeling to better understand the influence of alteration on volcano stability, using La Soufrière de Guadeloupe (Eastern Caribbean) as a case study. Laboratory experiments on variably altered (advanced argillic alteration) blocks show that uniaxial compressive strength, Young's modulus, and cohesion decrease as a function of increasing alteration, but that …
La Valle dei Templi in epoca medioevale. Caratterizzazione antropologica e paleopatologica delle sepolture antistanti in Tempio della Concordia
2021
Riassunto ― Il lavoro presenta i risultati delle analisi bio-archeologiche effettuate su resti scheletrici umani rinvenuti in quattordici sepolture di epoca medioevale rinvenute nel Parco Archeologico della Valle dei Templi di Agrigento (Sicilia). L’obiettivo è stato l’acquisizione delle informazioni necessarie per la ricostruzione del profilo biologico di ciascun individuo, al fine di determinarne il sesso, la stima dell’età biologica alla morte, la stima della statura e la valutazione delle patologie e degli indicatori di stress occupazionale mediante le correnti metodologie e tecniche diagnostiche di tipo antropologico. Sebbene il cattivo stato di conservazione di alcuni individui non ne…
The unspeakable through the works of some contemporary Spanish composers
2016
The concept of unspeakable, as complex as it may be, can base itself on an experience of the sensitive, and find a common context in the events exceeding the limit and pointing a certain chaos. Those of the Spanish Civil War have constituted, by numerous aspects, examples of these unthinkable excesses. The impact of the environment on the creators has been heard in the thematic traces which are imperative in the works composed on the themes of death, violence or war: from the sound phenomena, some figures making sensitive the exceeding of the limit and chaotic connotation have been highlighted and echo what is beyond belief, as the destruction of man or the inaudibility of death. These figu…