Ceramic materials lead to underestimated DNA quantifications : a method for reliable measurements

In the context of investigating cell-material interactions or of material-guided generation of tissues, DNA quantification represents an elective method to precisely assess the number of cells attached or embedded within different substrates. Nonetheless, nucleic acids are known to electrostatically bind to ceramics, a class of materials commonly employed in orthopaedic implants and bone tissue engineering scaffolds. This phenomenon is expected to lead to a relevant underestimation of the DNA amount, resulting in erroneous experimental readouts. The present work aims at *lpar;i) investigating the effects of DNA-ceramic bond occurrence on DNA quantification, and (ii) developing a method to reliably extract and accurately quantify DNA in ceramic-containing specimens. A cell-free model was adopted to study DNA-ceramic binding, highlighting an evident DNA loss (up to 90%) over a wide range of DNA/ceramic ratios (w/w). A phosphate buffer-based (800 mM) enzymatic extraction protocol was developed and its efficacy in terms of reliable DNA extraction and measurement was confirmed with commonly used fluorometric assays, for various ceramic substrates. The proposed buffered DNA extraction technique was validated in a cell-based experiment showing 95% DNA retrieval in a cell seeding experiment, demonstrating a 3.5-fold increase in measured DNA amount as compared to a conventional enzymatic extraction protocol. In conclusion, the proposed phosphate buffer method consistently improves the DNA extraction process assuring unbiased analysis of samples and allowing accurate and sensitive cell number quantification on ceramic containing substrates

Four-Quark Mesons in Non-leptonic B Decays--Could They Resolve Some Old Puzzles?

We point out that non-leptonic B decays driven by b-->ccbar s should provide a favourable environment for the production of hidden charm diquark-antidiquark bound states that have been suggested to explain the resonances with masses around 4 GeV recently observed by BaBar and BELLE. Studying their relative abundances in non-leptonic B decays can teach us novel lessons about their structure and the strong interactions. Through their decay into psi they can provide a natural explanation of the excess of B-->psi X observed for p_psi < 1 GeV. Other phenomenological consequences are mentioned as well.Comment: 6 pages, 2 figures, revte

Web based 3D quantitative measurements of abdominal aortic aneurysms

We tested a novel approach for the quantitative remote analysis of abdominal aortic aneurysms by reconstructing their 3D geometry and topological structure (i.e. centereline path) and put them on the web as VRML97 models including specialized code enabling the user to perform guided inspection and measurements useful for surgical planning

Time-Domain Analysis of Chalcogenide Threshold Switching: From ns to ps Scale

A space- and time-dependent theoretical model based on a trap-assisted, charge-transport framework for the amorphous phase of a chalcogenide material is used here to interpret available experimental results for the electric current of nanoscale devices in the ns–ps time domain. A numerical solution of the constitutive equations of the model for a time-dependent bias has been carried out for GST-225 devices. The “intrinsic” rise time of the device current after the application of a suitable external bias is controlled by the microscopic relaxation of the mobile-carrier population to the steady-state value. Furthermore, the analysis is extended to include the effect of the external circuit on the electrical switching. A quantitative estimate of the current delay time due to unavoidable parasitic effects is made for the optimised electrical set up configurations recently used by experimental groups

Reconstructed SPECT images of 177Lu homogeneous cylindrical phantom used for calibration and texture analysis

In a clinical contest, it is common to use dedicated phantoms to perform quality assurance test to check the performance of a SPECT system. Some of these phantoms are also used to calibrate the system for dosimetric evaluation of patients undergoing radiometabolic cancer therapy. In this work, a 3D-OSEM reconstructed Lu-177 SPECT dataset of a homogeneous cylindrical phantom is described. This dataset was acquired to investigate the variation of the SPECT calibration factor, counts convergence, noise and uniformity by varying the number of subsets and iterations. In particular, the dataset is composed of images reconstructed using five different numbers of subsets and sixteen different numbers of iterations, for a total of 80 different configurations. The dataset is suitable for comparison with other reconstruction algorithms (e.g. FBP, MLEM, etc.) and radionuclides (e.g. technetium, yttrium). In regards to the uniformity issue, the same dataset allows the user to perform radiomic investigations on the influence of the border effect on the reconstructed images

A complete one-loop calculation of electroweak supersymmetric effects in tt-channel single top production at LHC

We have computed the complete one-loop electroweak effects in the MSSM for single top (and single antitop) production in the $t$-channel at hadron colliders, generalizing a previous analysis performed for the dominant $dt$ final state and fully including QED effects. The results are quite similar for all processes. The overall Standard Model one-loop effect is small, of the few percent size. This is due to a compensation of weak and QED contributions that are of opposite sign. The genuine SUSY contribution is generally quite modest in the mSUGRA scenario. The experimental observables would therefore only practically depend, in this framework, on the CKM $Wtb$ coupling.Comment: 25 pages, several eps figures. Update corresponding to published versio

Beyond-CMOS Artificial Neuron: A simulation-based exploration of the molecular-FET

The recent growth of Artificial Neural Networks fueled the design of numerous Artificial Intelligence (AI) dedicated hardware implementations. High power dissipation, computational complexity, and large area footprints currently limit CMOS based real-time embedded AI applications. In this work, we design and simulate through SPICE, for the first time, an artificial analog neuron based on the molecular Field-Effect Transistor (molFET) technology. MolFETs are described by a circuital model whose physical characteristics are extracted from atomistic simulations. The designed neuron is a single column of a crossbar-like circuit representing a layer of seven parallel neurons. The drain currents sum up in a soma-like circuit - modelled through a comparator - and trigger the output pulses. We demonstrate the advantages of the molFET in terms of area, power, and speed by comparing it with a conventional MOSFET implementation. The results confirm the molecular technology is a promising candidate for accomplishing high neuron throughput capability and massive redundancy, still providing high energy efficiency. The obtained results foster further investigation of molFET technology both at the device and circuit level

Source inversion of seismic events recorded in the Larderello geothermal area

The Larderello geothermal field is a wide thermal anomaly located in the western part of Tuscany (Italy). Geophysical investigations in this area suggest a crustal thinning and intrusion of hot mantle material into the crust. The local seismicity, monitored since 1978 by a network of 26 short period almost vertical seismic stations, is characterized by a several hundred of M 1.5 events per year, never exceeding M=3.2 in the past 25 years. At December 2004 ENEL and INGV started a scientific collaboration, which includes also exchange of selected datasets. One of the main tasks is to perform source inversion of low magnitude seismic events recorded in the Larderello geothermal area. This is of particular interest, because such earthquakes could show similarities with seismic events recorded on active volcanoes. In order to record also seismic events below magnitude M = 1 the gain of the ENEL-seismic network is set rather sensitive. This implicates that seismograms of events with magnitudes M > 2.0 are recorded by the entire network, but at low epicentral distances the traces are often saturated, making a waveform inversion impossible. On the other hand, smaller events are not strong enough to be recorded also at the more external stations of the network. In both cases this trade-off results in a limited number of vertical component recordings available for the inversion. A further difficulty by performing source inversion of small seismic events is to fit the high frequencies. Therefore we applied the moment tensor (MT) inversion both in the time domain as well as in the frequency domain and compared the results. Source inversion was performed both for the full MT as well as by introducing constraints for doubles couple e/o CLVD. The source inversions of events occurred in the Travale area show a high double couple percentage and show no indications for an isotropic source. This seems to indicate a source mechanism which is typical for tectonic events

Biological phosphorus and nitrogen removal in a full scale sequencing batch reactor treating piggery wastewater

Research activities carried out at ENEA during the last few years allowed the development of a Sequencing Batch Reactor (SBR) that is able to remove biologically organic waste, nitrogen and phosphorus and that was shown to be particularly suited to obtaining low effluent nutrient concentrations even starting from concentrated wastes. Research on optimisation of time cycles and on process modelling, allowed an advanced comprehension of reactor behaviour and the development of a process able to obtain more than 98% removal of nitrogen, phosphorus and COD, and therefore almost capable of matching effluent standards with a sole biological process. On the basis of laboratory results and process modelling, a full scale SBR plant has been designed and realised. This plant, in ten months of operation, is achieving even better results compared to the laboratory ones

Prevalence and genetic parameters for hip dysplasia in Italian population of purebred dogs

This paper aimed to assess the prevalence of hip dysplasia (HD) in some breeds of dogs widely diffused in Italy and to estimate heritability of HD in German Shepherd and Boxer Italian populations. Data consisted of radiographic findings taken on 32,900 dogs (18,665 females and 14,225 males) of 7 breeds (German Shepherd; Boxer; Labrador Retriever; Golden Retriever; Rottweiler; Dobermann; Cane Corso) screened at an age of 17.9 ± 7.0 months. Radiographs of the coxofemoral joints, taken by 478 veterinarians, were scored for HD grade by a single veterinarian panelist according to a grading procedure based on a 5-class linear system (from A, no signs of dysplasia, to E, severe dysplastic hip changes). Logistic regression analysis was used for studying the relationships between selected explanatory variables with the out- come of the diagnosis for HD. Variance components, direct and maternal heritability have been estimated for German Shepherd and Boxer dogs using a REML animal model procedure. Prevalence of HD (hip joint graded C or worse) for the pool of breeds involved approached 22%, with large differences among breeds. In dogs diagnosed as dysplastic, the mild form (grade C) was largely prevalent for all breeds. When compared to the German Shepherd, the Cane Corso exhibit- ed a significantly higher risk, whereas the Dobermann, Labrador and Rottweiler showed a significantly lower risk of being affected by HD. The probability of being diagnosed as dysplastic increased with the increasing of the age of dogs at screening and with the decreasing of experience of x-raying veterinarians. The effect of birth year of dogs on the out- come of the HD diagnosis was significant, but evidenced an inconsistent trend through years. Heritability estimates approached 0.24 and 0.15 for Boxers and German Shepherds, respectively, whereas maternal heritability was close to 0.03 for both breeds. Results from this study demonstrated that HD is fairly prevalent in some breeds of dogs common- ly found in Italy, and its reduction should be a goal in breeding schemes of purebred dogs. Age at screening and expe- rience of the x-raying veterinarians are disturbance factors to be considered in screening programs for HD. Heritability estimates for HD was low, but additive genetic variance seems enough for conjecturing selection programs aimed to decrease hip joints disease. Given the low heritability values, current selection schemes based on phenotypic records seem ineffective, whereas the use of breeding values estimated under BLUP animal model procedures should be recom- mended for gaining genetic progress of Italian dog populations