Mass concentrations of PM2.5, mineral dust, organic carbon (OC) and elemental carbon (EC), water-soluble organic carbon (WSOC), sea salts and anthropogenic metals have been studied in a city-port of ...south Italy (Brindisi). This city is characterized by different emission sources (ship, vehicular traffic, biomass burning and industrial emissions) and it is an important port and industrial site of the Adriatic sea. Based on diagnostic ratios of carbonaceous species we assess the presence of biomass burning emissions (BBE), fossil fuel emissions (FFE) and ship emission (SE). Our proposed conversion factors from OC to OM are higher than those reported in the literature for urban site: the reason of this could be due to the existence of aged combustion aerosols during the sampling campaign (WSOC/OC=0.6±0.3).
•Diagnostic ratios were used to assess carbonaceous particle sources.•POC, SOC were estimated in two wind direction: harbour and urban-industrial area.•Mass closure approach was used to estimate the OC to OM conversion factor.•SIA, SOA, carbonaceous fractions, sea salts and crustal fraction were determined.
PM10 samples were collected simultaneously at three representative areas (urban, industrial, and rural areas). Their morphology and elemental composition were determined by scanning electron ...microscopy coupled with energy-dispersive analysis (SEM-EDS). Twenty-four chemical parameters (C, O, Na, Mg, Al, Si, P, Cd, Cl, K, Ca, S, Sn, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, W, and Pb) were determined and three morphological parameters (area, roundness, and fractal dimension) were measured by Image Pro Analyzer 6.3. The particles were classified into ten groups based on morphology and elemental composition: Ca-rich and metal particles, soot aggregates, cenosphere, alumosilicates, sea salt, calcium sulfate, spherical particles of iron, biological carbonaceous particles, and various. Particles of natural origin were predominantly found in the coarse size fraction and particles of anthropogenic origin in the fine size fraction. The greatest contribution to particulate matter belonged to aluminum-silicates and calcium-rich particles. The cenosphere were recognized only in the coastal urban site, while all the other particles were present in each site. The coastal industrial site was characterized by the prevalence of alumosilicates and Ca-rich particles, due to construction activity in this site during the sampling period (movement of vehicles, transport of terrigenous materials, and use of construction products). The coastal urban site was characterized by a higher amount of soot and by the presence of cenosphere, due to the presence of vehicular traffic.
Atmospheric aerosols have potential effects on human health, on the radiation balance, on climate, and on visibility. The understanding of these effects requires detailed knowledge of aerosol ...composition and size distributions and of how the different sources contribute to particles of different sizes. In this work, aerosol samples were collected using a 10-stage Micro-Orifice Uniform Deposit Impactor (MOUDI). Measurements were taken between February and October 2011 in an urban background site near Lecce (Apulia region, southeast of Italy). Samples were analysed to evaluate the concentrations of water-soluble ions (SO42−, NO3−, NH4+, Cl−, Na+, K+, Mg2+ and Ca2+) and of water-soluble organic and inorganic carbon. The aerosols were characterised by two modes, an accumulation mode having a mass median diameter (MMD) of 0.35±0.02μm, representing 51±4% of the aerosols and a coarse mode (MMD=4.5±0.4μm), representing 49±4% of the aerosols. The data were used to estimate the losses in the impactor by comparison with a low-volume sampler. The average loss in the MOUDI-collected aerosol was 19±2%, and the largest loss was observed for NO3− (35±10%). Significant losses were observed for Ca2+ (16±5%), SO42− (19±5%) and K+ (10±4%), whereas the losses for Na+ and Mg2+ were negligible. Size-segregated source apportionment was performed using Positive Matrix Factorization (PMF), which was applied separately to the coarse (size interval 1–18μm) and accumulation (size interval 0.056–1μm) modes. The PMF model was able to reasonably reconstruct the concentration in each size-range. The uncertainties in the source apportionment due to impactor losses were evaluated. In the accumulation mode, it was not possible to distinguish the traffic contribution from other combustion sources. In the coarse mode, it was not possible to efficiently separate nitrate from the contribution of crustal/resuspension origin.
•Size-segregated source apportionment of aerosol was performed using PMF.•Limits in identification of traffic and nitrate aerosol sources were discussed.•Losses of chemicals in the multi-stage impactor were estimated as 19% of PM10.•The effects of impactor losses on source apportionment were assessed.•The method used allowed reasonable apportionment of accumulation and coarse mode.
Abstract
Background
The Epstein-Barr virus (EBV) causes various B-cell lymphomas and epithelial malignancies, including gastric cancer (GC) at frequencies ranging from 5 to 10% in adenocarcinomas ...(ADK) to 80% in GC with lymphoid stroma (GCLS). Using high-sensitivity methods, we recently detected EBV traces in a large cohort of EBV-negative B-cell lymphomas, suggesting a
hit-and-run
mechanism.
Methods
Here, we used routine and higher-sensitivity methods droplet digital PCR (ddPCR) for EBV segments on microdissected tumour cells and RNAscope for
EBNA1
mRNA to assess EBV infection in a cohort of 40 GCs (28 ADK and 12 GCLS).
Results
ddPCR documented the presence of EBV nucleic acids in rare tumour cells of several cases conventionally classified as EBV-negative (ADK, 8/26; GCLS, 6/7). Similarly, RNAscope confirmed EBNA1 expression in rare tumour cells (ADK, 4/26; GCLS, 3/7). Finally, since EBV induces epigenetic changes that are heritable and retained after complete loss of the virus from the host cell, we studied the methylation pattern of EBV-specifically methylated genes (
Timp2
,
Eya1
) as a mark of previous EBV infection. Cases with EBV traces showed a considerable level of methylation in
Timp2
and
Eya1
genes that was similar to that observed in EBER-ISH positive cases and greater than cases not featuring any EBV traces.
Conclusions
These findings suggest that: (a) EBV may contribute to gastric pathogenesis more widely than currently acknowledged and (b) indicate the methylation changes as a mechanistic framework for how EBV can act in a
hit-and-run
manner. Finally, we found that the viral state was of prognostic significance in univariate and multivariate analyses.
The myotonic dystrophies (DM1, DM2) are the most common adult muscle diseases and are characterized by multisystem involvement. DM1 has been described in diverse populations, whereas DM2 seems to ...occur primarily in European Caucasians. Both are caused by the expression of expanded microsatellite repeats. In DM1, there is a reservoir of premutation alleles; however, there have been no reported premutation alleles for DM2. The (CCTG)(DM2) expansion is part of a complex polymorphic repeat tract of the form (TG)(n)(TCTG)(n)(CCTG)(n)(NCTG)(n)(CCTG)(n). Expansions are as large as 40 kb, with the expanded (CCTG)(n) motif uninterrupted. Reported normal alleles have up to (CCTG)(26) with one or more interruptions.
To identify and characterize potential DM2 premutation alleles, we cloned and sequenced 43 alleles from 23 individuals. Uninterrupted alleles were identified, and their instability was confirmed by small-pool PCR. We determined the genotype of a nearby single nucleotide polymorphism (rs1871922) known to be in linkage disequilibrium with the DM2 mutation.
We identified three classes of large non-DM2 repeat alleles: 1) up to (CCTG)(24) with two interruptions, 2) up to (CCTG)(32) with up to four interruptions, and 3) uninterrupted (CCTG)(22-33). Large non-DM2 alleles were more common in African Americans than in European Caucasians. Uninterrupted alleles were significantly more unstable than interrupted alleles (p = 10(-4) to 10(-7)). Genotypes at rs1871922 were consistent with the hypothesis that all large alleles occur on the same haplotype as the DM2 expansion.
We conclude that unstable uninterrupted (CCTG)(22-33) alleles represent a premutation allele pool for DM2 full mutations.
The unprecedented capabilities of state-of-the-art segmented germanium-detector arrays, such as AGATA and GRETA, derive from the possibility of performing pulse-shape analysis. The comparison of the ...net- and transient-charge signals with databases via grid-search methods allows the identification of the
γ
-ray interaction points within the segment volume. Their precise determination is crucial for the subsequent reconstruction of the
γ
-ray paths within the array via tracking algorithms, and hence the performance of the spectrometer. In this paper the position uncertainty of the deduced interaction point is investigated using the bootstrapping technique applied to
60
Co radioactive-source data. General features of the extracted position uncertainty are discussed as well as its dependence on various quantities, e.g. the deposited energy, the number of firing segments and the segment geometry.
► Composition of soils and resuspended PM10 was obtained in different sites. ► Enriched elements had larger abundances in resuspended PM10. ► Spatial variability of abundances were estimated for ...several soil categories. ► A two-threshold scheme for evaluation of enrichment of PM10 was developed. ► Thresholds values for local and planetary references were evaluated.
In this work, the inorganic chemical profiles of soil samples collected at different sites in the Salentum peninsula (Italy, Apulia region) are discussed. The samples were re-suspended in the laboratory, for PM10 sampling, using a ventilated wooden chamber and were then chemically analysed measuring the abundances of 17 elements. Different land use categories of soils (olive grove, arable land, vineyards, sand, and urban dust) were included in the 50 samples analysed: 45 collected in background areas and five collected in the urban area of Lecce. The objectives were to compare the chemical profiles of raw soil and re-suspended PM10 for different crustal sources and to estimate the potential improvements in the calculation of the enrichment factors of atmospheric PM10. The variability of elemental abundances in samples of the same category of soil collected in different zones was of the same order of magnitude as the differences observed between the various categories of soil. This allows the calculation of a weighted average composition of soil and urban dust and the corresponding weighted average composition of re-suspended PM10. In re-suspended PM10 from average background soil, all of the elements except Ca, Na, K and V have larger abundances with respect to raw soil. In urban dust, this is limited to Ca, V and Mg. The crustal enrichment factors (EFs) of atmospheric PM10 were evaluated by considering different reference elements and different reference tables. Results indicated that it is possible to apply a two-threshold (S1 and S2) scheme for the interpretation of EF, with thresholds derived from uncertainty in soil categories and from the choice of the reference element. A specific element is likely of crustal origin if EF<S1 and likely of anthropogenic origin if EF>S2. Between the two thresholds, the element can be considered of mixed origin. The thresholds vary according to the geological composition used in the evaluation of EF. If the average composition of local re-suspended soils is used, the thresholds are S1=2 and S2=4. If raw soil is used, the thresholds become S1=5 and S2=10. If the average upper-crust composition from literature data is used, the thresholds further increase to S1=10 and S2=20.
Background
Comprehensive datasets quantifying the coupled thermo-mechanical and electrical properties of shape memory alloys (SMAs) are lacking, as are standardized techniques for robust ...characterization. This hampers accurate modeling and design of SMA-based components. Objective: This work develops an automated experimental system to enable simultaneous measurement of stress-strain-temperature behavior and electrical resistivity evolution in NiTi SMA wires under controlled stress conditions. Methods: Customized test frames apply precise mechanical stresses while allowing for
in situ
electrical measurements and infrared imaging during complete thermal cycling protocols. Specialized instrumentation including a Keithley 2002 multimeter, Agilent E3631A programmable power supply, and FLIR A615 thermal camera are integrated with LabVIEW-based software routines for complete automation of the characterization process. Rigorous metrology principles are implemented throughout the measurement procedure to improve accuracy, repeatability, and consistency compared to prior manual techniques. Results: Extensive datasets are generated which reveal pronounced stress-dependencies in key SMA material parameters including transformation temperatures, recoverable strain, and electrical resistivity. A 3D regression model describes the comprehensive relationship between resistivity, temperature, and applied stress across the entire characterization domain. Conclusions: The automated measurement framework and methodology establishes a foundation for high-fidelity, reliable acquisition of coupled SMA property data. This will enable more accurate modeling and design of components and systems incorporating SMA actuation or sensing functions.
In this work a new original amperometric sensor for H(2)O(2) detection based on a Pt electrode modified with Te-microtubes was developed. Te-microtubes, synthesized by the simple thermal evaporation ...of Te powder, have a tubular structure with a hexagonal cross-section and are open ended. Modified electrode was prepared by direct drop casting of the mixture of Te-microtubes dispersed in ethanol on Pt surface. The spectroscopic characterization of synthesized Te-microtubes and Pt/Te-microtubes modified electrodes was performed by scanning electron microscopy (SEM), energy-dispersive X-rays microanalysis (EDX), X-ray diffraction analysis (XRD) and X-ray photoelectron spectroscopy (XPS). Moreover a complete electrochemical characterization of the new composite material Pt/Te-microtubes was performed by cyclic voltammetry (CV) and cronoamperometry (CA) in phosphate buffer solution (PBS) at pH 7. Electrochemical experiments showed that the presence of Te-microtubes on modified electrode was responsible for an increment of both cathodic and anodic currents in presence of H(2)O(2) with respect to bare Pt. Specifically, data collected from amperometric experiments at -150 mV vs. SCE in batch and -200 mV vs. SCE in flow injection analysis (FIA) experiments show a remarkable increment of the cathodic current. The electrochemical performances of tested sensors make them suitable for the quantitative determination of H(2)O(2) substrate both in batch and in FIA.
The structure of 74Se at low energy was investigated via spectroscopy of internal conversion electrons at the INFN Legnaro National Laboratories (LNL). A set of internal K-conversion coefficients and ...monopole transition strengths was measured. A large ρ2(E0;22+→21+)⋅103=210(130) value was deduced. This result, in addition to a low upper limit for the 03+→02+ electron transition, casts in doubt a simple interpretation of the 74Se low-lying structure, in particular the recently proposed spherical, vibrational character. New microscopic beyond-mean-field calculations generally agree with the experimental results and are capable of producing a large ρ2(E0;22+→21+) value, even if still a factor ≈7 smaller than the experiment. Triaxiality and a complex shape-coexistence and mixing scenario seem responsible for this unexpected experimental result.
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