31 research outputs found
Environmental impacts of using desalinated water in concrete production in areas affected by freshwater scarcity
Up to 500 litres of water may be consumed at the batching plant per cubic meter of ready mix concrete, if water for washing mixing trucks and equipment is included. Demand for concrete is growing almost everywhere, regardless of local availability of freshwater. The use of freshwater for concrete production exacerbates stress on natural water resources. In water-stressed coastal countries such as Israel, desalinated seawater (DSW) is often used in the production of concrete. However, the environmental impacts of this practice have not yet been assessed. In this study the effect of using DSW on the water and carbon footprints of concrete was investigated using life cycle assessment. Water footprint results highlight the benefits of using DSW rather than freshwater to produce concrete in Israel. In contrast, because desalination is an energy intensive process, using DSW increases the greenhouse gas intensity of concrete. Nevertheless, this increase (0.27 kg CO2e/m3 concrete) is small, if compared to the life cycle greenhouse gas emissions of concrete. Our results show that using untreated seawater in the mix (transported by truck from the coast) in place of DSW, would be beneficial in terms of water and carbon footprints if the batching plant were located less than 13 km from the withdrawal point. However, use of untreated seawater increases steel reinforcement corrosion, resulting in loss of structural integrity of the reinforced concrete composite. Sustainability of replacing steel with non-corrosive materials should be explored as a way to reduce both water and carbon footprints of concrete
Genome-wide Analyses Identify KIF5A as a Novel ALS Gene
To identify novel genes associated with ALS, we undertook two lines of investigation. We carried out a genome-wide association study comparing 20,806 ALS cases and 59,804 controls. Independently, we performed a rare variant burden analysis comparing 1,138 index familial ALS cases and 19,494 controls. Through both approaches, we identified kinesin family member 5A (KIF5A) as a novel gene associated with ALS. Interestingly, mutations predominantly in the N-terminal motor domain of KIF5A are causative for two neurodegenerative diseases: hereditary spastic paraplegia (SPG10) and Charcot-Marie-Tooth type 2 (CMT2). In contrast, ALS-associated mutations are primarily located at the C-terminal cargo-binding tail domain and patients harboring loss-of-function mutations displayed an extended survival relative to typical ALS cases. Taken together, these results broaden the phenotype spectrum resulting from mutations in KIF5A and strengthen the role of cytoskeletal defects in the pathogenesis of ALS.Peer reviewe
Multiancestry analysis of the HLA locus in Alzheimer’s and Parkinson’s diseases uncovers a shared adaptive immune response mediated by HLA-DRB1*04 subtypes
Across multiancestry groups, we analyzed Human Leukocyte Antigen (HLA) associations in over 176,000 individuals with Parkinson’s disease (PD) and Alzheimer’s disease (AD) versus controls. We demonstrate that the two diseases share the same protective association at the HLA locus. HLA-specific fine-mapping showed that hierarchical protective effects of HLA-DRB1*04 subtypes best accounted for the association, strongest with HLA-DRB1*04:04 and HLA-DRB1*04:07, and intermediary with HLA-DRB1*04:01 and HLA-DRB1*04:03. The same signal was associated with decreased neurofibrillary tangles in postmortem brains and was associated with reduced tau levels in cerebrospinal fluid and to a lower extent with increased Aβ42. Protective HLA-DRB1*04 subtypes strongly bound the aggregation-prone tau PHF6 sequence, however only when acetylated at a lysine (K311), a common posttranslational modification central to tau aggregation. An HLA-DRB1*04-mediated adaptive immune response decreases PD and AD risks, potentially by acting against tau, offering the possibility of therapeutic avenues
Greenhouse gas implications of extending the service life of PEM fuel fells for automotive applications: a life cycle assessment
A larger adoption of hydrogen fuel-cell electric vehicles (FCEVs) is typically included in the strategies to decarbonize the transportation sector. This inclusion is supported by life-cycle assessments (LCAs), which show the potential greenhouse gas (GHG) emission benefit of replacing internal combustion engine vehicles with their fuel cell counterpart. However, the literature review performed in this study shows that the effects of durability and performance losses of fuel cells on the life-cycle environmental impact of the vehicle have rarely been assessed. Most of the LCAs assume a constant fuel consumption (ranging from 0.58 to 1.15 kgH2/100 km) for the vehicles throughout their service life, which ranges in the assessments from 120,000 to 225,000 km. In this study, the effect of performance losses on the life-cycle GHG emissions of the vehicles was assessed based on laboratory experiments. Losses have the effect of increasing the life-cycle GHG emissions of the vehicle up to 13%. Moreover, this study attempted for the first time to investigate via laboratory analyses the GHG implications of replacing the hydrophobic polymer for the gas diffusion medium (GDM) of fuel cells to increase their durability. LCA showed that when the service life of the vehicle was fixed at 150,000 km, the GHG emission savings of using an FC with lower performance losses (i.e., FC coated with fluorinated ethylene propylene (FEP) instead of polytetrafluoroethylene (PTFE)) are negligible compared to the overall life-cycle impact of the vehicle. Both the GDM coating and the amount of hydrogen saved account for less than 2% of the GHG emissions arising during vehicle operation. On the other hand, when the service life of the vehicle depends on the operability of the fuel cell, the global warming potential per driven km of the FEP-based FCEV reduces by 7 to 32%. The range of results depends on several variables, such as the GHG emissions from hydrogen production and the initial fuel consumption of the vehicle. Higher GHG savings are expected from an FC vehicle with high consumption of hydrogen produced with fossil fuels. Based on the results, we recommend the inclusion of fuel-cell durability in future LCAs of FCEVs. We also advocate for more research on the real-life performance of fuel cells employing alternative materials
Life Cycle Assessment of a Wall Made of Prefabricated Hempcrete Blocks
Hempcrete is a natural building material obtained mixing hemp shives (i.e., the woody core
of the hemp plant) with a lime-based binder and water. Hempcrete as construction material is gaining
increasing interest as the EU aims to achieve net zero emissions by 2050. This material has, in fact,
the ability to uptake carbon dioxide from air (i.e., via carbonation) and to store carbon for long time.
The goal of the present work is to deeper analyze the environmental profile of hempcrete, in order to
assess its potentials in reducing emissions of construction sector. Specifically, Life Cycle Assessment
(LCA) of a non-load-bearing wall made of hempcrete blocks is carried on. The analysis encompasses
the whole life cycle from the extraction of raw materials to the end of the service life. The analyzed
blocks are produced by an Italian company. Only aerial lime is used as binder, microorganisms are
added to the blocks to accelerate carbonation. The impact on climate change is assessed through the
GWP 100 method proposed by IPCC. Preliminary results reveal a nearly neutral carbon budget
Microstructural Characterization of Prefabricated Hempcrete Blocks
Sustainable building materials have been developed to reduce the polluting emissions and the exploitation of natural resources of the building sector. Among these materials, an outstanding category is that of nature-based solutions which are produced recovering waste or by-products of agricultural cultivations and using them as vegetal aggregates to replace the traditional ones. This paper focusses on hempcrete which is produced mixing the by-product of industrial hemp cultivation (i.e., shives) and lime to obtain a sustainable, breathable and insulating material. The strength of hempcrete develops through carbonation of the binder that, leading to the formation of calcium or magnesium carbonates and mineralization of shives, determines the microstructure and hence most of the characteristic properties of the material. The aim of this research is to investigate how carbonation influences the microstructure of hempcrete when different recipes are used for blocks production. This study consists in the characterization of the material through techniques such as XRD (X-ray Diffractometry), SEM (Scanning Electron Microscopy) and TG-DTG (thermogravimetric analyses). Moreover, the evolution of carbonation is studied analyzing samples at different maturation times. The investigation of the carbonation reaction degree is also crucial to evaluate the environmental performances of the material because it allows the quantification of the carbon dioxide uptake. Also, periodic characterization allows to assess the durability of hempcrete and to select the best formulation according to the designed application and the corresponding service conditions
Valutazione della composizione dietetica di un gruppo di ultracentenari residenti in Lombardia
Functional and Environmental Performances of Novel Electrolytic Membranes for PEM Fuel Cells: A Lab-Scale Case Study
Despite being the most employed polymer electrolyte for proton exchange membrane fuel cells (PEMFCs), Nafion® has several limitations: expensiveness, poor performance when exposed to temperatures higher than 80 °C, and its potential as a source of environmentally persistent and toxic compounds (i.e., per- and polyfluoroalkyl substances, known as PFASs) when disposed of. This work explores the functional and environmental performances of three potential PFAS-free alternatives to Nafion® as electrolytic membranes in PEMFCs: sulfonated graphene oxide (SGO), graphene oxide-naphthalene sulfonate (GONS), and borate-reinforced sulfonated graphene oxide (BSGO). Investigated via ATR-FTIR spectroscopy, TGA, and cross-sectional SEM, the membranes show an effective functionalization of GO and good thermal stability. Functional properties are determined via Ion Exchange Capacity (IEC) evaluation, Electrochemical Impedance Spectroscopy, and tensile tests. In terms of IEC, the innovative materials outperform Nafion® 212. Proton conductivities at 80 °C of SGO (1.15 S cm−1) and GONS (1.71 S cm−1) are higher than that of the commercial electrolyte (0.56 S cm−1). At the same time, the membranes are investigated via Life Cycle Assessment (LCA) to uncover potential environmental hotspots. Results show that energy consumption during manufacture is the main environmental concern for the three membranes. A sensitivity analysis demonstrates that the impact could be significantly reduced if the production procedures were scaled up. Among the three alternatives, SGO shows the best trade-off between proton conductivity and environmental impact, even though performance results from real-life applications are needed to determine the actual environmental consequences of replacing Nafion® in PEMFCs
Alzheimer’s Disease Diagnosis: Discrepancy between Clinical, Neuroimaging, and Cerebrospinal Fluid Biomarkers Criteria in an Italian Cohort of Geriatric Outpatients: A Retrospective Cross-sectional Study
BackgroundThe role of cerebrospinal fluid (CSF) biomarkers, and neuroimaging in the diagnostic process of Alzheimer’s disease (AD) is not clear, in particular in the older patients.ObjectiveThe aim of this study was to compare the clinical diagnosis of AD with CSF biomarkers and with cerebrovascular damage at neuroimaging in a cohort of geriatric patients.MethodsRetrospective analysis of medical records of ≥65-year-old patients with cognitive impairment referred to an Italian geriatric outpatient clinic, for whom the CSF concentration of amyloid-β (Aβ), total Tau (Tau), and phosphorylated Tau (p-Tau) was available. Clinical diagnosis (no dementia, possible and probable AD) was based on the following two sets of criteria: (1) the Diagnostic Statistical Manual of Mental Disorders (DSM-IV) plus the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer’s Disease and Related Disorders Association (NINCDS-ADRDA) and (2) the National Institute on Aging-Alzheimer’s Association (NIA-AA). The Fazekas visual scale was applied when a magnetic resonance imaging scan was available.ResultsWe included 94 patients, mean age 77.7 years, mean Mini Mental State Examination score 23.9. The concordance (kappa coefficient) between the two sets of clinical criteria was 70%. The mean CSF concentration (pg/ml) (±SD) of biomarkers was as follows: Aβ 687 (±318), Tau 492 (±515), and p-Tau 63 (±56). There was a trend for lower Aβ and higher Tau levels from the no dementia to the probable AD group. The percentage of abnormal liquor according to the local cutoffs was still 15 and 21% in patients without AD based on the DSM-IV plus NINCDS-ADRDA or the NIA-AA criteria, respectively. The exclusion of patient in whom normotensive hydrocephalus was suspected did not change these findings. A total of 80% of patients had the neuroimaging report describing chronic cerebrovascular damage, while the Fazekas scale was positive in 45% of patients overall, in 1/2 of no dementia or possible AD patients, and in about 1/3 of probable AD patients, with no difference across ages.ConclusionWe confirmed the expected discrepancy between different approaches to the diagnosis of AD in a geriatric cohort of patients with cognitive impairment. Further research is needed to understand how to interpret this discrepancy and provide clinicians with practical guidelines
Vasculopatici sottoposti ad esercizio fisico allenante: nitriti/nitrati ed adesività piastinica
Vasculopatici sottoposti ad esercizio fisico allenante: nitriti/nitrati ed adesività piastinic