inkjet sensors produced by consumer printers with smartphone impedance readout

Abstract Inkjet printing technology is showing a disruptive potential for low-cost optical and electrochemical biosensors fabrication. This technology is becoming affordable for every laboratory, potentially allowing every research group to implement a biosensors fabrication platform with consumer inkjet printers, commercially available inks and smartphones for readout. In the present work we developed an example of such platform testing several inks, printers, and substrates. We defined and optimized the protocols assessing the printing limits and the fabricated biosensors electrochemical properties in standard solutions. Our platform has a total cost of less than 450 Euro and a single sensor fabrication cost of 0.026 Euro. Finally, we tested the sensitivity of smartphone-performed impedance measurements with printed biosensors surface coverage by Self Assembling Monolayers (SAM), validating them with standard instruments

Phase II trial of neoadjuvant pemetrexed plus cisplatin followed by surgery and radiation in the treatment of pleural mesothelioma

BACKGROUND: Malignant pleural mesothelioma is an aggressive tumor that has a poor prognosis and is resistant to unimodal approaches. Multimodal treatment has provided encouraging results. METHODS: Phase II, open-label study of the combination of chemotherapy (pemetrexed 500 mg/m(2)+cisplatin 75 mg/m(2) IV every 21 days × 3 cycles), followed by surgery (en-bloc extrapleural pneumonectomy, 3–8 weeks after chemotherapy) and hemithoracic radiation (total radiation beam 54 Gy, received 4–8 weeks post-surgery). The primary endpoint was event-free survival, defined as the time from enrollment to time of first observation of disease progression, death due to any cause, or early treatment discontinuation. RESULTS: Fifty-four treatment-naïve patients with T1-3 N0-2 malignant pleural mesothelioma were enrolled, 52 (96.3%) completed chemotherapy, 45 (83.3%) underwent surgery, 22 (40.7%) completed the whole treatment including 90-day post-radiation follow-up. The median event-free survival was 6.9 months (95%CI: 5.0-10.5), median overall survival was 15.5 months (95%CI 11.0-NA) while median time-to-tumor response was 4.8 months (95%CI: 2.5-8.0). Eighteen (33.3%) and 13 (24.1%) patients were still event-free after 1 and 2 years, respectively. The most common treatment-emergent adverse events were nausea (63.0%), anemia (51.9%) and hypertension (42.6%). Following two cardiopulmonary radiation-related deaths the protocol was amended (21 [38.9%] patients were already enrolled in the study): the total radiation beam was reduced from 54 Gy to 50.4 Gy and a more accurate selection of patients was recommended. CONCLUSIONS: The combination of pemetrexed plus cisplatin followed by surgery and hemithoracic radiation is feasible and has a manageable toxicity profile in carefully selected patients. It may be worthy of further investigation. TRIAL REGISTRATION: Clinicaltrial.com registrationID #NCT00087698

Galaxy Zoo: the interplay of quenching mechanisms in the group environment

Does the environment of a galaxy directly influence the quenching history of a galaxy? Here, we investigate the detailed morphological structures and star formation histories of a sample of SDSS group galaxies with both classifications from Galaxy Zoo 2 and near ultra-violet (NUV) detections in GALEX. We use the optical and NUV colours to infer the quenching time and rate describing a simple exponentially declining star formation history for each galaxy, along with a control sample of field galaxies. We find that the time since quenching and the rate of quenching do not correlate with the relative velocity of a satellite but are correlated with the group potential. This quenching occurs within an average quenching time-scale of ∼2.5 Gyr from star forming to complete quiescence, during an average infall time (from ∼10 R200 to 0.01 R200) of ∼2.6 Gyr. Our results suggest that the environment does play a direct role in galaxy quenching through quenching mechanisms that are correlated with the group potential, such as harassment, interactions or starvation. Environmental quenching mechanisms that are correlated with satellite velocity, such as ram-pressure stripping, are not the main cause of quenching in the group environment. We find that no single mechanism dominates over another, except in the most extreme environments or masses. Instead, an interplay of mergers, mass and morphological quenching and environment-driven quenching mechanisms dependent on the group potential drive galaxy evolution in groups

Effect of the relative shift between the electron density and temperature pedestal position on the pedestal stability in JET-ILW and comparison with JET-C

The electron temperature and density pedestals tend to vary in their relative radial positions, as observed in DIII-D (Beurskens et al 2011 Phys. Plasmas 18 056120) and ASDEX Upgrade (Dunne et al 2017 Plasma Phys. Control. Fusion 59 14017). This so-called relative shift has an impact on the pedestal magnetohydrodynamic (MHD) stability and hence on the pedestal height (Osborne et al 2015 Nucl. Fusion 55 063018). The present work studies the effect of the relative shift on pedestal stability of JET ITER-like wall (JET-ILW) baseline low triangularity (\u3b4) unseeded plasmas, and similar JET-C discharges. As shown in this paper, the increase of the pedestal relative shift is correlated with the reduction of the normalized pressure gradient, therefore playing a strong role in pedestal stability. Furthermore, JET-ILW tends to have a larger relative shift compared to JET carbon wall (JET-C), suggesting a possible role of the plasma facing materials in affecting the density profile location. Experimental results are then compared with stability analysis performed in terms of the peeling-ballooning model and with pedestal predictive model EUROPED (Saarelma et al 2017 Plasma Phys. Control. Fusion). Stability analysis is consistent with the experimental findings, showing an improvement of the pedestal stability, when the relative shift is reduced. This has been ascribed mainly to the increase of the edge bootstrap current, and to minor effects related to the increase of the pedestal pressure gradient and narrowing of the pedestal pressure width. Pedestal predictive model EUROPED shows a qualitative agreement with experiment, especially for low values of the relative shift

Characterization of Grating Coupled Surface Plasmon Polaritons Using Diffracted Rays Transmittance

A method to sense the excitation of surface plasmon polariton (SPP) on metallic grating device using the transmitted signal will be presented. The grating transmittance signal will be fully characterized varying the light incident angle and azimuthal grating orientation by means of the SPP vector model and rigorous coupled-wave analysis simulation. Simulation results will be compared with experimental measurements obtained with a 635 nm wavelength laser in the transverse magnetic polarization mode. The laser will light grating devices in contact with either air or water through a customized microfluidic chamber. A characterization of the diffracted rays will show the relationship between the grating coupling configuration and the Kretschmann one. In fact, the diffracted ray affected by SPP resonance is transmitted with an output angle which is the same incident angle that should be used to excite SPP in Kretschmann configuration. Lastly, the grating parameters (amplitude and metal thickness) impact on transmittance signal will be analyzed with respect to the order zero reflectance signal

Coadsorption optimization of DNA in binary self-assembled monolayer on gold electrode for electrochemical detection of oligonucleotide sequences

Optimization of the probe adsorption has a major key in the preparation of electrochemical sensors for the detection of oligonucleotide sequences hybridization. The role of a mixed monolayer of ssDNA sequences and MCH coadsorbed on a gold electrode surface was studied in this work. The working electrode was modified by chemisorption using a solution of thiol-tethered 33-mer DNA probe and mercaptohexanol (MCH), in a concentration range from 2 nM to 20 lM. The probe surface density was monitored by means of electrochemical impedance spectroscopy (EIS), differential pulse voltammetry (DPV) and chronocoulometry. From EIS measurements, the charge transfer resistance was obtained as a function of the MCH concentration in the immobilization solution. The time dependence of mixed SAM adsorption was also investigated. The SAM adsorption was characterized regarding the electrode surface coverage with DPV and EIS measurements. Moreover, the probe surface density was investigated with chronocoulometry in Ru\uf0NH3 e3\ufe 6 solution. Sensor behavior and sensitivity showed significant differences as a function of ssDNA/MCH concentration ratio as hybridization detection efficiency decreases while increasing the MCH concentration. The effect of different probe density in the hybridization detection efficiency was determined. Results demonstrated the effective of the coadsorption of ssDNA and thiols to control the SAM property and the probe density. It was therefore shown the importance to identify the correct density of probes on the electrode, below the saturation value, to ensure both a proper hybridization process and having a high hybridization signal

Identification, Purification and Characterization of Proteins with Cytotoxic/Antitumor Activity from Chondrosia reniformis

The majority of medicines come from natural resources, and in particular a great number of bioactive molecules (more than 10,000) have been isolated until now from the marine environment, with hundreds of new compounds still being discovered every year [1]. The richest sources of sea natural products are invertebrates with Porifera being the most prolific phylum. Sponge-derived bioactive compounds show the most varied activities: antifungal, anti-HIV, antiviral, antibacterial, but the predominant action is cytotoxic/antitumor with more than 800 compounds so far identified in this category. Sporadic observations on the behavior of the marine sponge Chondrosia reniformis pointed out a possible production of cytotoxic compounds in stress conditions able to kill neighboring organisms. The aim of this work was to purify and possibly characterize the compound causing said activity by means of a step by step purification followed by in vitro cytotoxicity analyses (MTT test) on a series of human tumor cell lines (leukemia, breast cancer, pulmonary carcinoma) as well as on healthy primary cells (fibroblast and blood mononuclear cells). The MTT tests showed a predominant cytotoxicity on tumor cells compared to healthy cells, thus pointing out a possible antitumor activity. Furthermore, preliminary experiments surprisingly showed that most cytotoxic/antitumor activity was confined to the protein fraction of the crude hydrophilic extract. Thus, different methods of protein fractionation were used to isolate the bioactive protein for a final high definition mass spectrometry (HD-MS) characterization. Namely, the purification steps were: a 10 kDa-cut-off dialysis, a 30% ammonium sulphate protein fractionation and a HPLC separation by gel filtration. After the latter step, a particular low-MW HPLC peak retained the antitumor activity, thus this fraction was separated in a 2D gel electrophoresis showing the presence of three protein bands. The bands from the gel were then trypsin-digested and the derived peptides analyzed in HD-MS obtaining the sequence of a series of peptides. Finally, through an in silico analysis comparing the peptide sequences to the C. reniformis transcriptome previously obtained in our lab, we were able to identify three possible protein candidates for the cytotoxic/antitumor activity: a protein with a trefoil factor domain and two unknown proteins showing no homology to known sequences. Actually, homologues of the first protein from higher Metazoa already show in literature an involvement in stress conditions, especially in epithelial injuries. Finally, we plan for the future to obtain the three proteins in recombinant form for further characterization studies. Research supported by EU (FP7 grant agreement n: 266033 SPonge Enzyme End Cell for Innovative AppLication-SPECIAL)

Evaluating Alpha-induced Soft Errors in Embedded Microprocessors

This paper presents the results of Alpha Single Event Upsets tests of an embedded 8051 microprocessor. Cross sections for the different memory resources (i.e., internal registers, code RAM, and user memory) are reported as well as the error rate for different codes implemented as test benchmarks. Test results are then discussed to find the contribution of each available resource to the overall device error rate