423 research outputs found
Numerical modeling of bifacial PV string performance: Perimeter effect and influence of uniaxial solar trackers
The bifacial photovoltaic (PV) systems have recently met large interest. The performance of such systems heavily depends on the installation conditions and, in particular, on the albedo radiation collected by the module rear side. Therefore, it is of crucial importance to have an accurate performance model. To date, in the scientific literature, numerous models have been proposed and experimental data collected to study and optimize bifacial PV system performance. Currently, 3D and 2D models of bifacial PV devices exist. Though the former are more mathematically complex, they can lead to more accurate results, since they generally allow to fully consider the main aspects influencing a bifacial PV system performance. Recently, we have proposed and validated through experimental data a 3D model tested as a function of module height, tilt angle, and ground albedo. In this work, through such a model, we studied the role played by the perimeter zones surrounding the PV string, by considering PV strings of 30 or 60 modules. We considered the cases of fixed installation with optimal PV module tilt and of installation with uniaxial horizontal solar tracker. We evaluated the PV energy yield as a function of the size of the perimeter zones for the two cases, i.e., both with and without the solar tracker. In optimal perimeter conditions, we then studied the behavior of bifacial and mono-facial PV strings by varying the geographical location in a large latitude range
Comparison of the intestinal microbiome of italian patients with multiple sclerosis and their household relatives
Multiple sclerosis (MS) is a chronic immune-mediated disease of the central nervous system, caused by a combination of genetic and environmental factors. In recent years, a role in MS pathogenesis was assigned to the gut microbiota. However, different signatures of gut dysbiosis have been shown to depend on environmental factors, like diet and lifestyle. In this study, we compared the gut microbiome in MS patients and their household healthy relatives sharing lifestyle and environmental factors. Faecal metagenomic DNA was extracted and the V3-V4 regions of the conserved bacterial 16S ribosomal RNA gene were amplified and sequenced. While overall bacterial communities were similar, specific families differed between healthy and MS subjects. We observed an increase in Ruminococcaceae, Christensenellaceae, Desulfovibrionaceae, Clostridiales, and Family XIII in MS patients, while Bacteroidaceae, Tannerellaceae, Veillonellaceae, and Burkholderiaceae were more abundant in healthy controls. In addition, principle coordinate analysis showed that the gut microbiome of all MS patients formed a cluster being less diverse than the household relatives and that gut microbiota of MS patients with EDSS 4.5-7 formed a distinct cluster in respect to their controls. Overall, our study is consistent with the hypothesis that MS patients have gut microbial dysbiosis and evidenced the importance of environmental factors in shaping the gut microbiome
Implementing quality by design for biotech products: are regulators on track?
Quality by design (QbD) is an innovative approach to drug development that has started to be implemented into the regulatory framework, but currently mainly for chemical drugs. The recent marketing authorization of the first monoclonal antibody developed using extensive QbD concepts in the European Union paves the way for future further regulatory approvals of complex products employing this cutting-edge technological concept. In this paper, we report and comment on insights and lessons learnt from the non-public discussions in the European Medicines Agency's Biologicals Working Party and Committee for Medicinal Products
for Human Use on the key issues during evaluation related to the implementation of an extensive QbD approach for biotechnology-derived medicinal products. Sharing these insights could prove useful for future developments in QbD for biotech products in general and monoclonal antibodies in particular
Trace elements in stomach oil of Scopoli's shearwater (Calonectris diomedea) from Linosa's colony
Calonectris diomedea is a colonial Procellariiform breeding on Mediterranean islands. The stomach oil produced during chick rearing is a peculiar trait of this species. The composition of the stomach oil is likely to reflect the composition of the prey ingested and might reveal the contaminants uptake with prey becoming a possible tool for the marine pollution monitoring. We examined the concentration of 15 trace elements by ICP-MS and direct mercury analyser. The principal component analysis revealed a heterogeneous pattern of metal concentration, showing a significant separation between samples collected 20 and 70 days after hatching. The data obtained in this work give preliminary information on the feeding habits and breeding ecology of Linosa's colony of Scopoli's shearwater. The trace metals variability found suggest that the stomach oil may have a role as trophic markers to understand predator-prey relationships and to have evidence on the accumulation of pollutants in the latter
OCT is not useful for detection of minimal diabetic retinopathy in type 1 diabetes.
Optical coherence tomography (OCT) has been proven useful in measuring retinal thickness (RT) in patients with diabetes, although with discordant results in different studies. We examined RT in patients with type 1 diabetes (T1D) with or without minimal diabetic retinopathy (MDR) to test whether OCT is able to identify early retinal changes and potential correlations with metabolic parameters. RT of 102 patients with T1D (53 females, 49 males, aged 27.03 +/- 7.4 years) and of 42 healthy controls was examined, with analysis of nine different sectors (fovea, four pericentral and four peripheral sectors). According to the results of basal fundus photography, patients were divided into two groups, without MDR (48 cases) and with MDR (54 cases). Patients with proliferative DR or macular edema were excluded. No difference was found between patients with or without MDR and the control group for all OCT parameters investigated. Mean HbA1c of the last 5 years (P < 0.001), microalbuminuria (P = 0.002), total (P = 0.046) and LDL cholesterol (P = 0.007) and triglyceride (P < 0.001) levels were higher in patients with MDR, along with higher prevalence of hypertension (P = 0.013), younger age at diagnosis (P = 0.018) and longer diabetes duration (P < 0.001) with regard to the patients without MDR and controls, although no significant correlation between these parameters and RT was found. Our study suggests that MDR without macular edema in patients with T1D cannot be detected with OCT. Therefore, the conventional diagnostic methods are mandatory to detect early DR
Calibration of input parameters in volcanic areas and an enlarged dataset by stochastic finite-fault simulations
The calibration of input parameters is an important task for stochastic finite-fault simulation in volcanic areas,
and we manage this in the framework of the European project UPStrat-MaFa. The stochastic simulation method
requires the knowledge of fault geometry, source, crust properties of the region, and local site effects. At first,
we focused the present study in the pilot test areas: Mt Vesuvius, Campi Flegrei and Mt Etna. Later, we
performed two applications for a large magnitude event in the Azores Islands and the South Iceland regions. A
general preliminary database of ground-motion records was collected in the test areas, to set up the empirical
laws of the ground-motion parameters. The results of the simulations have been compared with observed
waveforms and response spectra, to determine the suitability of the parameters used. The results show good
agreement between the observed and simulated time histories and response spectra, thus encouraging further
efforts towards quantitative high resolution studies on input parameters.Co-financed by the EU - Civil Protection Financial Instrument, in the framework the European project ”Urban disaster Prevention Strategies using MAcroseismic Fields and FAult Sources (Acronym: UPStrat-MAFA, Grant Agreement N. 23031/2011/613486/SUB/A5). http://ec.europa.eu/echo/funding/cp_projects2011_en.htmPublishedLisbon - Portugal4.1. Metodologie sismologiche per l'ingegneria sismicaope
Early magnesium reduction in advanced colorectal cancer patients treated with cetuximab plus irinotecan as predictive factor of efficacy and outcome
Introduction: Magnesium plays a role in a large number of cellular metabolic reactions.
Cetuximab is able to induce hypomagnesemia by interfering with magnesium (Mg2+) transport
in the kidney.We designed this trial to investigate if Mg2+ serum level modifications may be related
with clinical response andoutcome in advancedcolorectal cancer patients during treatment with
cetuximab plus irinotecan.
Experimental Design: Sixty-eight heavily pretreatedmetastatic colorectal cancer patients were
evaluatedfor Mg2+ serum levels at the following time points: before; 6 hours; and1, 7, 14, 21, 50,
and92 days after the start of treatment.
Results: Basal Mg2+ median levels were significantly decreased just 7 days after the first
anticancer infusion and progressively decreased from the 7th day onward, reaching the highest
significance at the last time point (P < 0.0001).Twenty-five patients showeda reduction in median
Mg2+ circulating levels of at least 20% within the 3rdweek after the first infusion. Patients with
this reduction showed a response rate of 64.0% versus 25.6% in the nonreduced Mg2+ group.
The median time to progression was 6.0 versus 3.6 months in the reduced Mg2+ group andin that
without reduction, respectively (P < 0.0001). Overall survival was longer in patients with Mg2+
reduction than in those without (10.7 versus 8.9 months).
Conclusions: Our results confirm that cetuximab treatment may induce a reduction of Mg2+
circulating levels andoffer the first evidence that Mg2+ reduction may represent a new predictive
factor of efficacy in advanced colorectal cancer patients treated with cetuximab plus irinoteca
Calibration of input parameters in volcanic areas and an enlarged dataset by stochastic finite-fault simulations
The calibration of input parameters is an important task for stochastic finite-fault simulation in volcanic areas,
and we manage this in the framework of the European project UPStrat-MaFa. The stochastic simulation method
requires the knowledge of fault geometry, source, crust properties of the region, and local site effects. At first,
we focused the present study in the pilot test areas: Mt Vesuvius, Campi Flegrei and Mt Etna. Later, we
performed two applications for a large magnitude event in the Azores Islands and the South Iceland regions. A
general preliminary database of ground-motion records was collected in the test areas, to set up the empirical
laws of the ground-motion parameters. The results of the simulations have been compared with observed
waveforms and response spectra, to determine the suitability of the parameters used. The results show good
agreement between the observed and simulated time histories and response spectra, thus encouraging further
efforts towards quantitative high resolution studies on input parameters
A Real-Life Study on the Use of Tildrakizumab in Psoriatic Patients
tildrakizumab is a humanized IgG1 kappa monoclonal antibody that selectively targets the p19 subunit of interleukin IL-23, thereby inhibiting the IL-23/IL-17 axis, which is primarily implicated in the immunopathogenesis of psoriasis. Tildrakizumab is approved for the treatment of moderate-to-severe plaque-type psoriasis in adults based on the evidence of two randomized and controlled phase-III clinical trials (reSURFACE 1 and reSURFACE 2). Here, we report our real-life experience treating 53 psoriatic patients (19 female and 34 male) who were administered tildrakizumab every 12 weeks and received follow-ups over 52 weeks. descriptive and inferential statistical analyses were performed, in particular the psoriasis area and severity Index (PASI), dermatology life quality Index (DLQI) and, if applicable, the Nail Psoriasis Severity Index (NAPSI) and Palmoplantar psoriasis physician global assessment (PPPGA). these were assessed at baseline and after different timepoints (weeks) during the follow-up period. we described and evaluated demographical and epidemiological characteristics in our cohort group, focusing on comorbidities. In this group, 35.9% of patients were female and 64.1% were male, with 47.1% being smokers and with a mean age of 51.2 years. a total of 37.7% of these patients was affected by scalp psoriasis; regarding comorbidities, hypertension was the most frequent (32.5%), followed by psoriatic arthritis (PsA) (18.60%) and diabetes (13.9%). at week 52, 93%, 90.2% and 77% of patients achieved a PASI reduction >= 75% (PASI 75), PASI 90 and PASI 100, respectively. In addition, NAPSI, PPPGA and DLQI scores were significantly reduced by week 52. In our cohort of complex psoriasis patients, disease remission began at the end of the fourth week of treatment and remained constant from week 16 to week 52
PML as a potential predictive factor of oxaliplatin/fluoropyrimidine-based first line chemotherapy efficacy in colorectal cancer patients
PML regulates a wide range of pathways involved in tumorigenesis, such as apoptosis, which is also one of the main mechanisms through which oxaliplatin and fluoropyrimidine exert their antineoplastic activity. The present study aims to investigate PML expression as a predictive factor of oxaliplatin/fluoropyrimidine therapy efficacy.
EXPERIMENTAL DESIGN:
74 metastatic colorectal cancer patients who received oxaliplatin/floropyrimidine-based first line therapy have been included in this retrospective study. PML expression was assessed by immunohistochemistry.
RESULTS:
PML down-regulation was detected in 39 (52.7%) patients (14 complete and 25 partial PML loss). RR was significantly lower (25.6%) in patients with PML down-regulation than in patients with preserved PML expression (60%) (P\u2009=\u20090.006). Median TTP was 5.5 months when PML was down-regulated versus 11.9 months in case of preserved PML expression (P\u2009<\u20090.0001). A statistical significant difference was also detected in OS (15.6 and 24.5 months respectively, P\u2009=\u20090.003). The impact of PML down-regulation on TTP and OS was statistically significant also in a multivariate model.
CONCLUSIONS:
This study represents the first evidence of a possible correlation between PML protein expression and outcome of metastatic colorectal cancer patients treated with oxaliplatin/fluoropyrimidine-based first line therapy
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