A 3D numerical approach to assess the temporal evolution of settlement damage to buildings on cavities subject to weathering

The goal of this paper is to show how a recently developed advanced hydro-chemo-mechanical (HCM) coupled constitutive and numerical model for soft rocks can be applied to predict the temporal evolution of settlement damage to buildings on cavities subject to weathering. In particular, a building damage index (BDI) and its evolution with time is proposed. The definition of the BDI is inspired by the work of Boscardin and Cording (1989) and uses the surface differential settlements obtained by finite element (FE) analyses to assess how far a building is from a non-acceptable service condition. By modelling the reactive transport of chemical species in 3D and using a coupled Chemo-Hydro-Mechanical (CHM) constitutive and numerical model, it is possible to simulate weathering scenarios and monitor the temporal evolution of surface settlements making the BDI time dependent. This approach is applied to evaluate the damage evolution of two buildings lying on two anthropic caves in a calcarenite deposit belonging to the Calcarenite di Gravina Formation. Standard and advanced experimental tests are performed on the in-situ material and the results are used to calibrate the constitutive model. The soundness of both constitutive relationship and reactive transport solver is subsequently tested by simulating two laboratory scale boundary value experiments. The first is a model footing test on dry and wet calcarenite while the second is a small scale pillar that, after the saturation induced short-term water weakening, fails due to a long term dissolution weathering process. Finally, both 2 and 3D coupled finite element (FE) analyses simulating different weathering scenarios and corresponding settlements affecting the buildings above the considered cavities are presented. Particular attention is placed on assessing the BDI and its temporal evolution

Widespread horizontal transfer of mitochondrial genes in flowering plants

Horizontal gene transfer - the exchange of genes across mating barriers - is recognized as a major force in bacterial evolution(1,2). However, in eukaryotes it is prevalent only in certain phagotrophic protists and limited largely to the ancient acquisition of bacterial genes(3-5). Although the human genome was initially reported(6) to contain over 100 genes acquired during vertebrate evolution from bacteria, this claim was immediately and repeatedly rebutted(7,8). Moreover, horizontal transfer is unknown within the evolution of animals, plants and fungi except in the special context of mobile genetic elements(9-12). Here we show, however, that standard mitochondrial genes, encoding ribosomal and respiratory proteins, are subject to evolutionarily frequent horizontal transfer between distantly related flowering plants. These transfers have created a variety of genomic outcomes, including gene duplication, recapture of genes lost through transfer to the nucleus, and chimaeric, half-monocot, half-dicot genes. These results imply the existence of mechanisms for the delivery of DNA between unrelated plants, indicate that horizontal transfer is also a force in plant nuclear genomes, and are discussed in the contexts of plant molecular phylogeny and genetically modified plants.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62688/1/nature01743.pd

Horizontal acquisition of multiple mitochondrial genes from a parasitic plant followed by gene conversion with host mitochondrial genes

Background: Horizontal gene transfer (HGT) is relatively common in plant mitochondrial genomes but the mechanisms, extent and consequences of transfer remain largely unknown. Previous results indicate that parasitic plants are often involved as either transfer donors or recipients, suggesting that direct contact between parasite and host facilitates genetic transfer among plants. Results: In order to uncover the mechanistic details of plant-to-plant HGT, the extent and evolutionary fate of transfer was investigated between two groups: the parasitic genus Cuscuta and a small clade of Plantago species. A broad polymerase chain reaction (PCR) survey of mitochondrial genes revealed that at least three genes (atp1, atp6 and matR) were recently transferred from Cuscuta to Plantago. Quantitative PCR assays show that these three genes have a mitochondrial location in the one species line of Plantago examined. Patterns of sequence evolution suggest that these foreign genes degraded into pseudogenes shortly after transfer and reverse transcription (RT)- PCR analyses demonstrate that none are detectably transcribed. Three cases of gene conversion were detected between native and foreign copies of the atp1 gene. The identical phylogenetic distribution of the three foreign genes within Plantago and the retention of cytidines at ancestral positions of RNA editing indicate that these genes were probably acquired via a single, DNA-mediated transfer event. However, samplings of multiple individuals from two of the three species in the recipient Plantago clade revealed complex and perplexing phylogenetic discrepancies and patterns of sequence divergence for all three of the foreign genes. Conclusions: This study reports the best evidence to date that multiple mitochondrial genes can be transferred via a single HGT event and that transfer occurred via a strictly DNA-level intermediate. The discovery of gene conversion between co-resident foreign and native mitochondrial copies suggests that transferred genes may be evolutionarily important in generating mitochondrial genetic diversity. Finally, the complex relationships within each lineage of transferred genes imply a surprisingly complicated history of these genes in Plantago subsequent to their acquisition via HGT and this history probably involves some combination of additional transfers (including intracellular transfer), gene duplication, differential loss and mutation-rate variation. Unravelling this history will probably require sequencing multiple mitochondrial and nuclear genomes from Plantago

Pattern of cancer risk in persons with AIDS in Italy in the HAART era

A record-linkage study was carried out between the Italian AIDS Registry and 24 Italian cancer registries to compare cancer excess among persons with HIV/AIDS (PWHA) before and after the introduction of highly active antiretroviral therapy (HAART) in 1996. Standardised incidence ratios (SIR) were computed in 21951 AIDS cases aged 16–69 years reported between 1986 and 2005. Of 101 669 person-years available, 45 026 were after 1996. SIR for Kaposi sarcoma (KS) and non-Hodgkin lymphoma greatly decreased in 1997–2004 compared with 1986–1996, but high SIRs for KS persisted in the increasingly large fraction of PWHA who had an interval of <1 year between first HIV-positive test and AIDS diagnosis. A significant excess of liver cancer (SIR=6.4) emerged in 1997–2004, whereas the SIRs for cancer of the cervix (41.5), anus (44.0), lung (4.1), brain (3.2), skin (non-melanoma, 1.8), Hodgkin lymphoma (20.7), myeloma (3.9), and non-AIDS-defining cancers (2.2) were similarly elevated in the two periods. The excess of some potentially preventable cancers in PWHA suggests that HAART use must be accompanied by cancer-prevention strategies, notably antismoking and cervical cancer screening programmes. Improvements in the timely identification of HIV-positive individuals are also a priority in Italy to avoid the adverse consequences of delayed HAART use

A transitioning Arctic surface energy budget: the impacts of solar zenith angle, surface albedo and cloud radiative forcing

Snow surface and sea-ice energy budgets were measured near 87.5°N during the Arctic Summer Cloud Ocean Study (ASCOS), from August to early September 2008. Surface temperature indicated four distinct temperature regimes, characterized by varying cloud, thermodynamic and solar properties. An initial warm, melt-season regime was interrupted by a 3-day cold regime where temperatures dropped from near zero to -7°C. Subsequently mean energy budget residuals remained small and near zero for 1 week until once again temperatures dropped rapidly and the energy budget residuals became negative. Energy budget transitions were dominated by the net radiative fluxes, largely controlled by the cloudiness. Variable heat, moisture and cloud distributions were associated with changing air-masses. Surface cloud radiative forcing, the net radiative effect of clouds on the surface relative to clear skies, is estimated. Shortwave cloud forcing ranged between -50 W m-2 and zero and varied significantly with surface albedo, solar zenith angle and cloud liquid water. Longwave cloud forcing was larger and generally ranged between 65 and 85 W m-2, except when the cloud fraction was tenuous or contained little liquid water; thus the net effect of the clouds was to warm the surface. Both cold periods occurred under tenuous, or altogether absent, low-level clouds containing little liquid water, effectively reducing the cloud greenhouse effect. Freeze-up progression was enhanced by a combination of increasing solar zenith angles and surface albedo, while inhibited by a large, positive surface cloud forcing until a new air-mass with considerably less cloudiness advected over the experiment area. © 2010 Springer-Verlag

An evaluation of Arctic cloud and radiation processes during the SHEBA year: simulation results from eight Arctic regional climate models

Eight atmospheric regional climate models (RCMs) were run for the period September 1997 to October 1998 over the western Arctic Ocean. This period was coincident with the observational campaign of the Surface Heat Budget of the Arctic Ocean (SHEBA) project. The RCMs shared common domains, centred on the SHEBA observation camp, along with a common model horizontal resolution, but differed in their vertical structure and physical parameterizations. All RCMs used the same lateral and surface boundary conditions. Surface downwelling solar and terrestrial radiation, surface albedo, vertically integrated water vapour, liquid water path and cloud cover from each model are evaluated against the SHEBA observation data. Downwelling surface radiation, vertically integrated water vapour and liquid water path are reasonably well simulated at monthly and daily timescales in the model ensemble mean, but with considerable differences among individual models. Simulated surface albedos are relatively accurate in the winter season, but become increasingly inaccurate and variable in the melt season, thereby compromising the net surface radiation budget. Simulated cloud cover is more or less uncorrelated with observed values at the daily timescale. Even for monthly averages, many models do not reproduce the annual cycle correctly. The inter-model spread of simulated cloud-cover is very large, with no model appearing systematically superior. Analysis of the co-variability of terms controlling the surface radiation budget reveal some of the key processes requiring improved treatment in Arctic RCMs. Improvements in the parameterization of cloud amounts and surface albedo are most urgently needed to improve the overall performance of RCMs in the Arctic

Using whole-plant chambers to estimate carbon and water fluxes in field-grown grapevines

There are limited studies available that have investigated the effects of different levels of water supply on the whole-plant gas exchange dynamics. The latter is related to the difficulty in measuring whole-canopy carbon fixation and water consumption, especially in field conditions. Whole-plant chambers can measure these fluxes, therefore the aims of this work were (i) to determine the relationship between whole-plant gas exchange compared to single leaf gas exchange; (ii) to validate whole-canopy chamber measurements using sap flow probes; (iii) to measure the effect of soil water availability on water use efficiency calculated from gas exchange measured using whole-plant chambers. For these purposes, an experiment was carried out during the 2014 season in an experimental vineyard using six-years-old plants of cv. Grenache. Two irrigation regimes were established, moderate irrigation (50 % ETo) and non-irrigation. Carbon fixation and transpiration were measured using whole-plant chambers at veraison and pre-harvest. Simultaneously, leaf gas exchange was measured at different canopy positions during the day in order to compare those measurements with the whole-plant chamber data. In parallel, sap flow measurements were continuously recorded using heat balance probes. Results showed that CO2 fixation measured at noon in sun exposed leaves oriented to the south presented the highest correlation coefficient with whole plant chamber data. Whole-plant transpiration measured with whole-plant chambers was slightly higher compared to the estimated from sap flow data in both irrigated and non-irrigated plants. In general intensive leaf-level measurements do not completely reflect the whole plant physiology, due to variability of leaf to leaf environmental conditions and plant regulation of gas exchange.This work has been developed with financial support from the Spanish Ministry of Economy project AGL2014-54201-C4-1, and the financial assistance by University of Balearic Island for visiting professors stays. We are indebted to Dr. Pérez Peña, Dr. Prieto (INTA, Argentina), and Mr. Pep Sastre (University of Balearic Island) during construction and commissioning of whole plant chambers. We would like to thank Mr. Miquel Truyols and collaborators of the UIB Experimental Field which are supported by the UIB Grant 15/2015 for their support to our experiments. We want to thanks Dr. Fuentes for English revision.Peer reviewe

Effect of leaf‐to‐fruit

BACKGROUND: The single high‐wire system is a free canopy trellis system suitable for warm to hot climates. In a global warming scenario, it arouses as a technological solution since it prevents berry overheating and sunburn. Canopy management practices manipulate leaf‐to‐fruit ratios, affecting berry and wine composition. We aimed to evaluate the phenolic and sensory profiles of Malbec wines from single high‐wire trellised vineyards in a hot region in Mendoza (Argentina) and to assess the effect of varying leaf‐to‐fruit ratios on these attributes. We manipulated leaf‐to‐fruit ratios by varying shoot trimming (experiment 1: 0.45 m, 0.80 m, and untrimmed) and winter pruning severity (experiment 2: 16, 24, 32, and >32 countable buds per meter). We characterized wine attributes by a descriptive analysis, color by the CIELAB space, and global phenolics compounds and anthocyanins by high‐performance liquid chromatography with diode array detection. RESULTS: We found that wines where shoots were trimmed to 0.80 m or left untrimmed had similar and greater intensity of color, violet hue, astringency, and alcohol and a richer aroma profile than wines where shoots were trimmed to 0.45 m. Meanwhile, wines from 16 and >32 buds/m treatments (the latter simulating a box pruning) were similar to each other and had higher color intensity, violet hue, acidity, alcohol, and astringency and a more complex aroma profile than the other pruning treatments. CONCLUSIONS: The best quality wines were achieved by leaving 16 or >32 buds/m and by trimming shoots to 0.80 m or leaving them untrimmed. The modulation of cultural practices in sprawling canopies offers the potential to produce wines with different styles in hot regions.EEA MendozaFil: Ahumada, Gastón E. Trapiche Winery; ArgentinaFil: Catania, Anibal Alejandro. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza. Laboratorio de Aromas y Sustancias Naturales; ArgentinaFil: Fanzone, Martín Leandro. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza. Laboratorio de Aromas y Sustancias Naturales; ArgentinaFil: Belmonte, Marcelo J. Trapiche Winery; ArgentinaFil: Giordano, Carla Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; ArgentinaFil: Gonzalez, Carina Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentin