| 1. |
- Frigerio, Jacopo, et al.
(author)
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Second Harmonic Generation in Germanium Quantum Wells for Nonlinear Silicon Photonics
- 2021
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In: ACS Photonics. - : American Chemical Society (ACS). - 2330-4022. ; 8:12, s. 3573-3582
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Journal article (peer-reviewed)abstract
- Second-harmonic generation (SHG) is a direct measure of the strength of second-order nonlinear optical effects, which also include frequency mixing and parametric oscillations. Natural and artificial materials with broken center-of-inversion symmetry in their unit cell display high SHG efficiency, however, the silicon-foundry compatible group IV semiconductors (Si, Ge) are centrosymmetric, thereby preventing full integration of second-order nonlinearity in silicon photonics platforms. Here we demonstrate strong SHG in Ge-rich quantum wells grown on Si wafers. Unlike Si-rich epilayers, Ge-rich epilayers allow for waveguiding on a Si substrate. The symmetry breaking is artificially realized with a pair of asymmetric coupled quantum wells (ACQW), in which three of the quantum-confined states are equidistant in energy, resulting in a double resonance for SHG. Laser spectroscopy experiments demonstrate a giant second-order nonlinearity at mid-infrared pump wavelengths between 9 and 12 μm. Leveraging on the strong intersubband dipoles, the nonlinear susceptibility χ(2) almost reaches 105 pm/V, 4 orders of magnitude larger than bulk nonlinear materials for which, by the Miller's rule, the range of 10 pm/V is the norm.
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| 2. |
- Barcaccia, Barbara, et al.
(author)
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Whom are you mad at? : Anger and revenge in obsessive-compulsive symptoms during adolescence
- 2022
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In: Journal of Obsessive-Compulsive and Related Disorders. - : Elsevier BV. - 2211-3649. ; 35
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Journal article (peer-reviewed)abstract
- Previous research has extensively explored the role of anxiety, disgust, guilt, and shame in obsessive-compulsive (OC) symptoms, but few studies have investigated anger and associated vengeful motivations, especially during adolescence, when OC symptoms typically onset. This is unfortunate as anger is a key human emotion linked to various aspects of behaviour. Our aim was to explore how anger and revenge motivations were associated with the most common OC subtypes in adolescents. Participants were 1035 high school students who completed a battery of questionnaires including the Obsessive-Compulsive Inventory-Child Version, the Children's Depression Inventory, the Transgression-Related Interpersonal Motivations Inventory-18 and the State-Trait Anger Expression Inventory for children and adolescents. Even when accounting for different aspects of anger, TRIMs and depression, trait anger (i.e., a stable tendency to experience anger) was uniquely associated with all types of OC symptoms (doubting/checking, obsessing, and ordering). Unique associations were also found between revenge motivation and doubting/checking and obsessing. Our findings show that adolescents with high OC symptoms may experience not only intense anger, but also vengeful feelings and motivations. Future research should examine how anger, vengeful motivations and OC symptoms co-develop over time. Clinicians should be aware that anger and vengeful motivations can be part of the clinical presentation of OCD, which can inform assessment and treatment.
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| 3. |
- Bollati, Michela, et al.
(author)
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Structure and functionality in flavivirus NS-proteins : perspectives for drug design
- 2010
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In: Antiviral Research. - : Elsevier BV. - 0166-3542 .- 1872-9096. ; 87:2, s. 125-148
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Research review (peer-reviewed)abstract
- Flaviviridae are small enveloped viruses hosting a positive-sense single-stranded RNA genome. Besides yellow fever virus, a landmark case in the history of virology, members of the Flavivirus genus, such as West Nile virus and dengue virus, are increasingly gaining attention due to their re-emergence and incidence in different areas of the world. Additional environmental and demographic considerations suggest that novel or known flaviviruses will continue to emerge in the future. Nevertheless, up to few years ago flaviviruses were considered low interest candidates for drug design. At the start of the European Union VIZIER Project, in 2004, just two crystal structures of protein domains from the flaviviral replication machinery were known. Such pioneering studies, however, indicated the flaviviral replication complex as a promising target for the development of antiviral compounds. Here we review structural and functional aspects emerging from the characterization of two main components (NS3 and NS5 proteins) of the flavivirus replication complex. Most of the reviewed results were achieved within the European Union VIZIER Project, and cover topics that span from viral genomics to structural biology and inhibition mechanisms. The ultimate aim of the reported approaches is to shed light on the design and development of antiviral drug leads.
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| 4. |
- Gaetani, Lorenzo, et al.
(author)
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Cerebrospinal fluid neurofilament light chain predicts disease activity after the first demyelinating event suggestive of multiple sclerosis
- 2019
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In: Multiple Sclerosis and Related Disorders. - : Elsevier BV. - 2211-0348 .- 2211-0356. ; 35, s. 228-232
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Journal article (peer-reviewed)abstract
- Background: The prediction of disease activity in patients with a first demyelinating event suggestive of multiple sclerosis (MS) is of high clinical relevance. Cerebrospinal fluid (CSF) neurofilament light chain (NfL) has shown to have prognostic value in MS patients. In this work, we measured CSF NfL in patients at the first demyelinating event in order to find a cut-off value able to discriminate patients who will have disease activity from those who will remain stable during the follow-up. Methods: We included CSF samples collected within 30 days after the onset of the first demyelinating event from 32 patients followed-up for 3.8 ± 2.5 years. CSF NfL was measured with a newly developed in-house enzyme linked immunosorbent assay (ELISA). Results: At the first demyelinating event, patients with subsequent disease activity had significantly higher baseline CSF NfL values compared to clinically and radiologically stable patients (median 812.5 pg/mL, range 205–2359 pg/mL vs 329.5 pg/mL, range 156–3492 pg/mL, p = 0.002). A CSF NfL cut-off value of 500 pg/mL significantly discriminated these two groups of patients with a 90% sensitivity and an 83.3% specificity. Conclusion: Our results confirm that CSF NfL is a prognostic marker in the very early phases of MS. The validation of a cut-off value of 500 pg/mL could provide clinicians with a dichotomous variable that can simplify the prognostic assessment of patients at the first demyelinating event.
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| 5. |
- Gaetani, Lorenzo, et al.
(author)
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The Immune Signature of CSF in Multiple Sclerosis with and without Oligoclonal Bands: A Machine Learning Approach to Proximity Extension Assay Analysis
- 2024
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In: International Journal of Molecular Sciences. - 1661-6596 .- 1422-0067. ; 25:1
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Journal article (peer-reviewed)abstract
- Early diagnosis of multiple sclerosis (MS) relies on clinical evaluation, magnetic resonance imaging (MRI), and cerebrospinal fluid (CSF) analysis. Reliable biomarkers are needed to differentiate MS from other neurological conditions and to define the underlying pathogenesis. This study aimed to comprehensively profile immune activation biomarkers in the CSF of individuals with MS and explore distinct signatures between MS with and without oligoclonal bands (OCB). A total of 118 subjects, including relapsing–remitting MS with OCB (MS OCB+) (n = 58), without OCB (MS OCB−) (n = 24), and controls with other neurological diseases (OND) (n = 36), were included. CSF samples were analyzed by means of proximity extension assay (PEA) for quantifying 92 immune-related proteins. Neurofilament light chain (NfL), a marker of axonal damage, was also measured. Machine learning techniques were employed to identify biomarker panels differentiating MS with and without OCB from controls. Analyses were performed by splitting the cohort into a training and a validation set. CSF CD5 and IL-12B exhibited the highest discriminatory power in differentiating MS from controls. CSF MIP-1-alpha, CD5, CXCL10, CCL23 and CXCL9 were positively correlated with NfL. Multivariate models were developed to distinguish MS OCB+ and MS OCB− from controls. The model for MS OCB+ included IL-12B, CD5, CX3CL1, FGF-19, CST5, MCP-1 (91% sensitivity and 94% specificity in the training set, 81% sensitivity, and 94% specificity in the validation set). The model for MS OCB− included CX3CL1, CD5, NfL, CCL4 and OPG (87% sensitivity and 80% specificity in the training set, 56% sensitivity and 48% specificity in the validation set). Comprehensive immune profiling of CSF biomarkers in MS revealed distinct pathophysiological signatures associated with OCB status. The identified biomarker panels, enriched in T cell activation markers and immune mediators, hold promise for improved diagnostic accuracy and insights into MS pathogenesis.
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| 6. |
- Grebe, Steffen, et al.
(author)
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Specific thylakoid protein phosphorylations are prerequisites for overwintering of Norway spruce (Picea abies) photosynthesis
- 2020
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In: Proceedings of the National Academy of Sciences of the United States of America. - : National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 117:30, s. 17499-17509
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Journal article (peer-reviewed)abstract
- Coping of evergreen conifers in boreal forests with freezing temperatures on bright winter days puts the photosynthetic machinery in great risk of oxidative damage. To survive harsh winter conditions, conifers have evolved a unique but poorly characterized photoprotection mechanism, a sustained form of nonphotochemical quenching (sustained NPQ). Here we focused on functional properties and underlying molecular mechanisms related to the development of sustained NPQ in Norway spruce (Picea abies). Data were collected during 4 consecutive years (2016 to 2019) from trees growing in sun and shade habitats. When day temperatures dropped below -4 degrees C, the specific N-terminally triply phosphorylated LHCB1 isoform (3p-LHCII) and phosphorylated PSBS (p-PSBS) could be detected in the thylakoid membrane. Development of sustained NPQ coincided with the highest level of 3p-LHCII and p-PSBS, occurring after prolonged coincidence of bright winter days and temperatures close to -10 degrees C. Artificial induction of both the sustained NPQ and recovery from naturally induced sustained NPQ provided information on differential dynamics and light-dependence of 3p-LHCII and p-PSBS accumulation as prerequisites for sustained NPQ. Data obtained collectively suggest three components related to sustained NPQ in spruce: 1) Freezing temperatures induce 3p-LHCII accumulation independently of light, which is suggested to initiate destacking of appressed thylakoid membranes due to increased electrostatic repulsion of adjacent membranes; 2) p-PSBS accumulation is both light -and temperature-dependent and closely linked to the initiation of sustained NPQ, which 3) in concert with PSII photoinhibition, is suggested to trigger sustained NPQ in spruce.
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| 7. |
- Mancini, Andrea, et al.
(author)
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Origin of the compositional diversity in the basalt-to-dacite series erupted along the Heidarspordur ridge, NE Iceland
- 2015
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In: Journal of Volcanology and Geothermal Research. - : Elsevier BV. - 0377-0273 .- 1872-6097. ; 301, s. 116-127
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Journal article (peer-reviewed)abstract
- The Heidarspordur ridge, located in the Northern Volcanic Zone of Iceland, was formed approximately 9000 years ago by a volcanic episode known as Ludent Fires. The episode produced a broad spectrum of different magma types, forming approximately 50 small scoria cones and two larger craters (Ludent and Hraunbunga). The bulk compositions cluster in five distinct groups: (1) olivine basalts, (2) Fe-Ti basalts, (3) basaltic icelandites, (4) icelandites, and (5) dacites. Major and trace element trends, together with mineral chemistry and isotopic ratios, suggest that the dominant process involved in generating the evolved magmas was crystal fractionation occurring at variable depth. An origin by polybaric differentiation is confirmed by MELTS modeling. Magma mixing played a dominant role in the formation of the basaltic icelandites. Additionally, the Fe-Ti basalts, which erupted shortly after the dacites and used approximately the same vent area, display unusually high concentrations of Fe, Ti, P, and Sr. Their composition is best explained by some pyroxene-dominated fractionation (prior to Fe-Ti oxide stability), and by entrainment of some crystal cumulate material at shallow depth, mostly left over from the silicic differentiation stage. Textural and chemical features of the minerals (e.g., presence of glomerocrysts, two populations of plagioclase in these basalts) support this interpretation of evolved cumulate remobilization. Fe-Ti basalts with the same field, compositional and textural characteristics have also been erupted in the nearby but magmatically independent Krafla Volcanic System, suggesting that a similar differentiation trend occurs also in this larger central volcano. (C) 2015 Elsevier B.V. All rights reserved.
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| 8. |
- Paolanti, Marina, et al.
(author)
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Machine Learning approach for Predictive Maintenance in Industry 4.0
- 2018
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In: 2018 14th IEEE/ASME International Conference on Mechatronic and Embedded Systems and Applications (MESA). - : Institute of Electrical and Electronics Engineers (IEEE). - 9781538646434 - 9781538646441
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Conference paper (peer-reviewed)abstract
- Condition monitoring together with predictive maintenance of electric motors and other equipment used by the industry avoids severe economic losses resulting from unexpected motor failures and greatly improves the system reliability. This paper describes a Machine Learning architecture for Predictive Maintenance, based on Random Forest approach. The system was tested on a real industry example, by developing the data collection and data system analysis, applying the Machine Learning approach and comparing it to the simulation tool analysis. Data has been collected by various sensors, machine PLCs and communication protocols and made available to Data Analysis Tool on the Azure Cloud architecture. Preliminary results show a proper behavior of the approach on predicting different machine states with high accuracy.
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| 9. |
- Zheng, Ju-Sheng, et al.
(author)
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Association between plasma phospholipid saturated fatty acids and metabolic markers of lipid, hepatic, inflammation and glycaemic pathways in eight European countries : a cross-sectional analysis in the EPIC-InterAct study
- 2017
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In: BMC Medicine. - : BioMed Central. - 1741-7015. ; 15
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Journal article (peer-reviewed)abstract
- Background: Accumulating evidence suggests that individual circulating saturated fatty acids (SFAs) are heterogeneous in their associations with cardio-metabolic diseases, but evidence about associations of SFAs with metabolic markers of different pathogenic pathways is limited. We aimed to examine the associations between plasma phospholipid SFAs and the metabolic markers of lipid, hepatic, glycaemic and inflammation pathways. Methods: We measured nine individual plasma phospholipid SFAs and derived three SFA groups (odd-chain: C15:0 + C17:0, even-chain: C14:0 + C16:0 + C18:0, and very-long-chain: C20:0 + C22:0 + C23:0 + C24:0) in individuals from the subcohort of the European Prospective Investigation into Cancer and Nutrition (EPIC)-InterAct case-cohort study across eight European countries. Using linear regression in 15,919 subcohort members, adjusted for potential confounders and corrected for multiple testing, we examined cross-sectional associations of SFAs with 13 metabolic markers. Multiplicative interactions of the three SFA groups with pre-specified factors, including body mass index (BMI) and alcohol consumption, were tested. Results: Higher levels of odd-chain SFA group were associated with lower levels of major lipids (total cholesterol (TC), triglycerides, apolipoprotein A-1 (ApoA1), apolipoprotein B (ApoB)) and hepatic markers (alanine transaminase (ALT), aspartate transaminase (AST), gamma-glutamyl transferase (GGT)). Higher even-chain SFA group levels were associated with higher levels of low-density lipoprotein cholesterol (LDL-C), TC/high-density lipoprotein cholesterol (HDL-C) ratio, triglycerides, ApoB, ApoB/A1 ratio, ALT, AST, GGT and CRP, and lower levels of HDL-C and ApoA1. Very-long-chain SFA group levels showed inverse associations with triglycerides, ApoA1 and GGT, and positive associations with TC, LDL-C, TC/HDL-C, ApoB and ApoB/A1. Associations were generally stronger at higher levels of BMI or alcohol consumption. Conclusions: Subtypes of SFAs are associated in a differential way with metabolic markers of lipid metabolism, liver function and chronic inflammation, suggesting that odd-chain SFAs are associated with lower metabolic risk and even-chain SFAs with adverse metabolic risk, whereas mixed findings were obtained for very-long-chain SFAs. The clinical and biochemical implications of these findings may vary by adiposity and alcohol intake.
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| 10. |
- Aad, G, et al.
(author)
-
- 2015
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swepub:Mat__t
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