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•Particle sizing accuracy of microfluidic Coulter-type devices with coplanar layout is limited by variability in particle path.•We present a method that significantly improves ...particle sizing accuracy without the need for particle focusing.•The method exploits the richness of the information contained in the measured traces, by means of simple signal-processing.
Microfluidic impedance-based devices with coplanar electrode layout represent an attractive tool for low-cost, label-free, single-cell analysis. However, their usefulness has long been limited by the positional dependence of the measured signals, i.e., identical particles traveling along different paths provide different traces. In this paper we show that it is possible to significantly reduce this unwanted effect via straightforward signal processing, by exploiting the richness of the information contained in the recorded traces.
During the interwar era, German naval history and naval doctrine exercised a profound influence on the development of the Italian Navy. The subject is relevant to understand how continental sea ...powers naval doctrines developed after the First World War, attempting to integrate new weapon systems to overcome the previous limits of the Fleet in being strategy. Italian naval thinkers incorporated the lessons offered by their German counterparts, preparing to repeat many of their mistakes, which explained in part the failures of Italian sea power in the early years of the Second World War.
The study and the characterization of cell death mechanisms are fundamental in cell biology research. Traditional death/viability assays usually involve laborious sample preparation and expensive ...equipment or reagents. In this work, we use electrical impedance spectroscopy as a label-free methodology to characterize viable, necrotic and apoptotic human lymphoma U937 cells. A simple three-electrode coplanar layout is used in a differential measurement scheme and thousands of cells are measured at high-throughput (≈200 cell/s). Tailored signal processing enables accurate and robust cell characterization without the need for cell focusing systems. The results suggest that, at low frequency (0.5 MHz), signal magnitude enables the discrimination between viable/necrotic cells and cell fragments, whereas phase information allows discriminating between viable cells and necrotic cells. At higher frequency (10 MHz) two subpopulations of cell fragments are distinguished. This work substantiates the prominent role of electrical impedance spectroscopy for the development of next-generation cell viability assays.
•Label-free cell viability assays are urgently needed in cell biology research.•We use a simple microfluidic impedance cytometer to study the viability of human lymphoma cells.•Tailored signal processing enables accurate high-throughput analysis without cell focusing mechanisms.•Electrical fingerprints discriminate between viable cells, necrotic cells and apoptotic bodies/cell debris.
Between 1940 and 1945 Italy experienced all the trials of total war. Subsequently, Italian historiography has focused on reconstructing the causes of civilian losses during the conflict. Much less ...attention has been paid to official recognition of, and assistance to, the members of the civil population who survived the conflict. This article will show how the inadequate legislative preparations made by the Fascist regime for total war had an adverse impact on requests for assistance from survivors. It will also reveal how the continuity between Fascism and the early Republican years as regards welfare and legislation continued to hamper victims' access to support and assistance. Finally, it explores how personal judicial battles conducted by individual victims shifted the paradigm of legislation and opened the way for a broader recognition of victims' rights by the state.
Studies of the relations between the Tripartite powers have primarily been concentrated on the relations of Nazi Germany with Imperial Japan and Fascist Italy. This article, based on original ...documents from the Italian archives, offers an original insight on the Italian perspective about the naval relations between Italy and Japan before and during the early years of the Second World War. It analyses the strategic motivation that led Fascist Italy to seek naval cooperation with Japan and how their relationship evolved during the period between the Ethiopian War (1935–6) to the end of the Axis campaign in North Africa in 1943.
Microfluidic impedance cytometry is a label-free technique for high-throughput single-cell analysis. Multi-frequency impedance measurements provide data that allows full characterisation of cells, ...linking electrical phenotype to individual biophysical properties. To efficiently extract the information embedded in the electrical signals, potentially in real-time, tailored signal processing is needed. Artificial intelligence approaches provide a promising new direction. Here we demonstrate the ability of neural networks to decipher impedance cytometry signals in two challenging scenarios: (i) to determine the intrinsic dielectric properties of single cells directly from raw impedance data streams, (ii) to capture single-cell signals that are hidden in the measured signals of coincident cells. The accuracy of the results and the high processing speed (fractions of ms per cell) demonstrate that neural networks can have an important role in impedance-based single-cell analysis.
We report the first generation of coherent, tunable, variable-polarization, soft X-ray femtosecond pulses, generated by a seeded free-electron laser (FEL) operating in the fresh bunch, two-stage ...harmonic upshift configuration. Characterization of the radiation proves this FEL configuration can produce single-transverse-mode, narrow-spectral-bandwidth output pulses of several tens of microjoules energy and low pulse-to-pulse wavelength jitter at final wavelengths of 10.8 nm and below. The fresh bunch configuration enhances the FEL emission at high harmonic orders by avoiding a gain depression due to the energy spread induced by the first-stage FEL interaction. Coherent signals measured down to 4.3 nm suggest this configuration is directly scalable to photon energies that will enable scientific investigations below the carbon K-edge, including access to the L-edges of many magnetic materials, with an energy per pulse unlocking the gate for experiments in the soft X-ray region with close to Fourier-transform-limited pulses.A seeded free-electron laser with a two-stage harmonic upshift configuration provided tunable and coherent soft-X-ray pulses. The configuration produced single-transverse-mode, narrow-spectral-bandwidth femtosecond pulses with energies of several tens of microjoules and a low pulse-to-pulse wavelength jitter at wavelengths of 10.8 nm and below.
Mammography remains the standard imaging modality for the identification and characterization of breast calcifications. However, its low specificity results in high biopsy rates in cases of ...suspicious calcifications.
To evaluate the diagnostic performance of MRI as an additional tool in the assessment of suspicious mammographic calcifications and to identify the enhancement patterns most related to malignancy.
An observational, prospective, cross-sectional, bi-centre study was conducted including consecutive patients with suspicious calcification groups on mammography (BI-RADS® 4 and 5). Anatomopathological results obtained from biopsies were considered the reference standard, and the patients were followed up for at least two years. MRI examinations were interpreted by two radiologists in consensus. The chi-square test was used to evaluate the correlation between MRI features and histological results. The overall diagnostic performance of MRI for malignancy was calculated.
162 female patients were included (mean age, 53 years; range 34–82 years), with 163 mammographic lesions, of which 77 (47.2%) were benign, 64 (39.3%) malignant, and 22 (13.5%) precursor lesions on histopathology. Malignant lesions demonstrated a significantly higher presence of enhancement (56/64; 87.5%) than benign lesions (17/77; 22.1%) (p < 0.001). Non-mass enhancement (NME) was the morphology most related to malignant lesions (38/56; 67.9%). The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of MRI for malignancy were 81.5%, 87.5%, 77.8%, 71.8%, and 90.5%, respectively.
MRI performed as an adjunct tool allows to increase imaging specificity for malignancy in suspicious calcifications, which may contribute to reduce the need for biopsy.
•MRI has a good accuracy for malignancy when used as an adjunct tool for assessment of suspicious mammary calcifications.•Non-mass enhancement was the morphology most related to malignant lesions.•The increased imaging specificity for malignancy allowed by MRI in this context may reduce the need for biopsy.
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