118 research outputs found

    numerical simulation analysis of the impact of photovoltaic systems and energy storage technologies on centralised generation a case study for australia

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    In response to climate change concerns, most of the industrialised countries have committed in recent years to increase their share of Renewable Energy Sources to reduce Greenhouse Gas emissions. Therefore, the rapid deployment of small-scale photovoltaic (PV) systems, mainly in residential applications, is starting to represent a considerable portion of the available electrical power generation and, for this reason, the stochastic and intermittent nature of these systems are affecting the operation of centralised generation (CG) resources. Network operators are constantly changing their approach to both short-term and long-term forecasting activities due to the higher complexity of the scenario in which more and more stakeholders have active roles in the network. An increasing number of customers must be treated as prosumers and no longer only as consumers. In this context, storage technologies are considered the suitable solution. These can be necessary in order to solve and fill the problems of the renewable distributed sources are introducing in the management of the network infrastructure. The aim of this work was to create a model in order to evaluate the impact of power generation considering PV systems in Australia along with a model to simulate Battery Energy Storage Systems (BESSs) and Electric Vehicles future contributions using MATLAB. The methodology used to develop these models was based on statistical assumptions concerning the available details about PV systems installed and current storage technologies. It has been shown that in all the scenarios analysed, the future adoption of rooftop PV panels and impact on the CG is incredibly higher than the uptake of energy storage systems. Hence, the influence on the demand will be driven by the behaviour of the PV systems. Only in the hypothetical scenario in which the installations of BESSs will assume comparable levels of the PV systems, it will be possible to better manage the centralised resources

    The Yin and Yang of the Bone Marrow Microenvironment: Pros and Cons of Mesenchymal Stromal Cells in Acute Myeloid Leukemia

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    Mesenchymal stromal cells (MSCs) have, for a long time, been recognized as pivotal contributors in the set up and maintenance of the hematopoietic stem cell (HSC) niche, as well as in the development and differentiation of the lympho-hematopoietic system. MSCs also have a unique immunomodulatory capacity, which makes them able to affect, both in vitro and in vivo, the function of immune cells. These features, namely the facilitation of stem cell engraftment and the inhibition of lymphocyte responses, have both proven essential for successful allogeneic stem cell transplantation (allo-SCT), which remains the only curative option for several hematologic malignancies. For example, in steroid-refractory acute graft-vs. host disease developing after allo-SCT, MSCs have produced significant results and are now considered a treatment option. However, more recently, the other side of the MSC coin has been unveiled, because of their emerging role in creating a protective and immune-tolerant microenvironment able to support the survival of leukemic cells and affect the response to therapies. In this light, it has been proposed that the failure of current treatments to efficiently override the stroma-mediated protection of leukemic cells accounts for the high rate of relapse in acute myeloid leukemia, at least in part. In this review, we will focus on emerging microenvironment-driven mechanisms conferring a survival advantage to leukemic cells overt physiological HSCs. This body of evidence increasingly highlights the opportunity to consider tumor-microenvironment interactions when designing new therapeutic strategies

    Work-related allergies to storage mites in Parma (Italy) ham workers

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    OBJECTIVES: To investigate the role of storage mites in the development of allergic diseases among ham production workers, and to search for early alterations in lung function tests and early inflammation markers in exhaled air. Respiratory allergies due to storage mites have been reported in people with various occupations but, although such mites are unavoidable when curing ham, there are no published data concerning ham production workers. SETTING: Secondary care. DESIGN: Experimental cross-sectional study. PARTICIPANTS: 220 participants (110 ham production workers and 110 controls) were recruited. PRIMARY AND SECONDARY OUTCOME MEASURES: Workers answered a medical questionnaire, and underwent spirometry and fraction of exhaled nitric oxide at 50 mL/s (FeNO50) measurements. Those with allergic symptoms also underwent skin prick tests to determine their sensitisation to airborne allergens. A methacholine test was performed in symptomatic participants when spirometry was normal to assess airways hyper-responsiveness. RESULTS: Symptomatic storage mite sensitisation was observed in 16 workers (14.5%) (rhinoconjunctivitis in 15 (63%) and asthma in (4%)) and 2 controls (1.8%; p=0.001). Higher FeNO50 values in exposed symptomatic workers compared with healthy control participants (34.65±7.49 vs 13.29±4.29 ppb; p<0.001) suggested bronchial and nasal involvement, although their lung function parameters were normal. Regardless of exposure, a FeNO50 value of 22.5 ppb seems to be 100% sensitive and 99.4% specific in distinguishing allergic and non-allergic participants. Multivariate analysis of FeNO50 values in the symptomatic participants showed that they were positively influenced by IgE-mediated allergy (p=0.001) and reported symptom severity (p=0.041), and negatively by smoking status (p=0.049). CONCLUSIONS: Ham processing workers, as well as workers involved in any meat processing work that includes curing, should be informed about the occupational risk of sensitisation to mites

    A Grid-based solution for management and analysis of microarrays in distributed experiments

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    Several systems have been presented in the last years in order to manage the complexity of large microarray experiments. Although good results have been achieved, most systems tend to lack in one or more fields. A Grid based approach may provide a shared, standardized and reliable solution for storage and analysis of biological data, in order to maximize the results of experimental efforts. A Grid framework has been therefore adopted due to the necessity of remotely accessing large amounts of distributed data as well as to scale computational performances for terabyte datasets. Two different biological studies have been planned in order to highlight the benefits that can emerge from our Grid based platform. The described environment relies on storage services and computational services provided by the gLite Grid middleware. The Grid environment is also able to exploit the added value of metadata in order to let users better classify and search experiments. A state-of-art Grid portal has been implemented in order to hide the complexity of framework from end users and to make them able to easily access available services and data. The functional architecture of the portal is described. As a first test of the system performances, a gene expression analysis has been performed on a dataset of Affymetrix GeneChip® Rat Expression Array RAE230A, from the ArrayExpress database. The sequence of analysis includes three steps: (i) group opening and image set uploading, (ii) normalization, and (iii) model based gene expression (based on PM/MM difference model). Two different Linux versions (sequential and parallel) of the dChip software have been developed to implement the analysis and have been tested on a cluster. From results, it emerges that the parallelization of the analysis process and the execution of parallel jobs on distributed computational resources actually improve the performances. Moreover, the Grid environment have been tested both against the possibility of uploading and accessing distributed datasets through the Grid middleware and against its ability in managing the execution of jobs on distributed computational resources. Results from the Grid test will be discussed in a further paper

    Pliocene Diatom Biomarkers in Sabrina Coast. EAIS Continental Marginal Dynamics

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    PNRA Tytan project, supported by the National Institute of Oceanography and Applied Geophysics (OGS), focused on the advances and retreats dynamics of the ice sheet and on variations in the glacial regime. Unit 2 focused on Diatom biomarkers and assemblages analysis on sediments of core PC03, collected during the IN2017-V01 cruise on the eastern flank of the Minang-a (or Whale) submarine Canyon. The project aims at reconstructing the depositional environment of the continental margin off the Totten Glacier and diatom data remained a key tools to constrain past ice-sheet dynamics and to forecasting future behaviour in a warming world. Preliminary dataset from diatom biostratigraphic tools allows to refer the base of the core to Pliocene while the upper part of the core records more modern EAIS dynamics, indicative of minor sedimentary evolution steps of the continental margin. Diatom assemblage analyses highlight Eocene-Oligocene reworked material and freshwater diatom inputs in Pliocene sequence, strengthening the debate about ice-sheet and paleoceanographic models, WAIS cyclic collapse and suspected Pliocene EAIS retreat into major subglacial Antarctic basins

    Sabrina Coast (East Antarctica) depositional processes highlightedthrough stratigraphic and paleoenvironmental diatom analysis

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    The systematic survey of Antarctic margin sedimentary sequences offers, especially in poorly investigated areas,the opportunity to obtain a wide range of information on glacio-eustatic, climatic, and tectonic events. Multi-disciplinary datasets resulting from geophysical surveys and scientific coring and drilling are needed to addressquestions regarding the orbital forcing and the global response of the hydrosphere (oceans and atmosphere),cryosphere, and biosphere. The PNRA Tytan Project, embedded into the Australian project \u201cInteractions of theTotten Glacier with the Southern Ocean through multiple glacial cycles\u201d (Australian National University), aimsto understand how the Totten Glacier behaved during past Holocene and Pleistocene times of warmer climate.Insights for reconstructing the depositional and hydrodynamic environments of the continental margin off theTotten Glacier, a large outlet glacier located on the Sabrina Coast of East Antarctica, are addressed throughmicropaleontological efforts. The micropaleontological research group focused on identification of diatombiostratigraphic markers and assemblage analyses in sediment cores collected from the Sabrina Coast continentalslope during the RV Investigator mission IN2017_V01 in order to reconstruct paleoenvironments and to place ageconstraints on the sedimentary sequences.All but one of the piston cores recovered late Pleistocene sediments, documenting MIS 9 \u2013 MIS 1, withinterglacial intervals characterized by diatomaceous sediments dominated by the open water taxon Fragilariopsiskerguelensis. Glacial intervals have much lower diatom concentrations and a higher proportion of reworked forms.A single piston core, IN2017_V01_PC03, recovered a more complicated sedimentary sequence. This sequence,targeted for an older and more condensed coring location, was selected for coring based on the sub-bottomgeophysical data that indicated thinning of the upper stratigraphic section, and greater access to the underlyingsection. The results suggest a very dynamic sediment delivery system in a context of Pliocene\u2013Recent Antarcticcontinental margin. The basal section of the core is marked by Eocene-Oligocene reworked taxa while the midsection is characterized by almost barren sediments. The silty top section of the PC03 core, had diatom assem-blages similar to the other kasten and piston cores; t his sectionis characterized by modern diatom assemblagesdominated by Circum Antarctic Current and open water taxa with a variable presence of sea ice associated forms.Glacial slumping, perhaps facilitated by the presence of biogenic silica, and reworking may have removed orprevented deposition within this condensed sedimentary sequence.The presence or absence of F. kerguelensis versus F. barronii and also the presence of transitional forms betweenthese two species, confirms the much older nature of the sediments in this core as compared to the other pistoncores. In addition, Denticulopsis simonsenii much more common at the basal part of the core, may reflect ero-sional contributions from Miocene-aged sediment, while the significant contribution of F. barronii, Thalassiosiralentiginosa and Thalassiosira oliverana (var. sparsa?) versus intervals dominated by D. simonsenii may suggestdifferent sources of material

    Clinical and Prognostic Significance of Serum IgG4 in Chronic Periaortitis. An Analysis of 113 Patients

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    Objective: Chronic periaortitis (CP) is a rare fibro-inflammatory disorder that incorporates idiopathic retroperitoneal fibrosis, inflammatory abdominal aortic aneurysms, and perianeurysmal retroperitoneal fibrosis. CP is included in the spectrum of IgG4-related disease. Since CP patients rarely undergo diagnostic biopsies, serum IgG4 levels are often used to classify CP as IgG4-related. However, the clinical and prognostic significance of serum IgG4 in CP is unknown.Methods: We measured serum IgG4 in active CP patients and compared the clinical characteristics, response to therapy and outcome of patients with high and normal levels. We also tested the diagnostic significance of IgG4 by comparing its levels in CP patients, healthy and disease controls (malignancies, Erdheim-Chester disease, large-, and small-vessel vasculitis).Results: We studied 113 consecutive patients with active CP. Twenty-four (21.2%) had high serum IgG4 (&gt;135 mg/dL). The demographic, laboratory, and clinical characteristics of patients with high and normal IgG4 were similar, and so were the rates of ureteral obstruction and the disease characteristics on CT, MRI, and 18F-FDG-PET. Patients with high IgG4 only had a higher frequency of extra-retroperitoneal fibro-inflammatory lesions (p = 0.005). There were no significant differences in response to therapy and relapses between the two groups. Serum IgG4 levels did not discriminate CP from controls.Conclusions: Serum IgG4 levels are high in a minority of CP patients and do not identify specific clinical or prognostic subgroups; only a higher frequency of extra-retroperitoneal lesions is found in high-IgG4 patients. Serum IgG4 levels do not help in the differential diagnosis between CP and its mimics
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