3,311 research outputs found
The Polito Surface Wave flat-file Database (PSWD): statistical properties of test results and some inter-method comparisons
The compilation and maintenance of experimental databases are of crucial importance in all research fields, allowing for researchers to develop and test new methodologies. In this work, we present a flat-file database of experimental dispersion curves and shear wave velocity profiles, mainly from active surface wave testing, but including also data from passive surface wave testing and invasive methods. The Polito Surface Wave flat-file Database (PSWD) is a gathering of experimental measurements collected within the past 25Â years at different Italian sites. Discussion on the database content is reported in this paper to evaluate some statistical properties of surface wave test results. Comparisons with other methods for shear wave velocity measurements are also considered. The main novelty of this work is the homogeneity of the PSWD in terms of processing and interpretation methods. A common processing strategy and a new inversion approach were applied to all the data in the PSWD to guarantee consistency. The PSWD can be useful for further correlation studies and is made available as a reference benchmark for the validation and verification of novel interpretation procedures by other researchers
Scientific basis of nanotechnology, implications for the food sector and future trends
Nanotechnologies are opening up new horizons in almost all
scientific and technological fields. Among these, applications
of nanotechnologies are expected to bring large benefits and
add value to the food and food-related industries through the current regulatory framework
whole food chain, from production to processing, safety, packaging,
transportation, storage and delivery. Nanotechnology
consists in the realization and manipulation of nano-sized
matter, the unique properties of which with respect to their
bulk counterparts are illustrated and discussed. Then, the
main tools and techniques routinely used in nanotechnology
for the nanoscale characterization of food matrices as well
as for the analytical determination of nanomaterials in food
samples are reviewed. Finally, safety and risk assessment issues
are discussed and an overview of applications of nanotechnology
to the food sector is provided along with a description of th
Study of MDT calibration constants using H8 testbeam data of year 2004
In year 2004 Atlas performed a long campaign of test beam data taking at the H8 Cern beam. Two sectors of the barrel and endcap regions of the Muon Spectrometer were exposed to the beam and large amount of data were collected in well defined and controlled operating conditions. This allowed a careful study on MDT drift properties. A better understanding of the calibration constants, of their definition and determination and of the criteria for their acceptance has been obtained. Systematic effects and time stability of the constants have also been studied
Ten years of pluviometric analyses in Italy for civil protection purposes
The concept of climate change has grown in recent decades, influencing the scientific community to conduct research on meteorological parameters and their variabilities. Research on global warming, as well as on its possible economic and environmental consequences, has spread over the last 20Â years. Diffused changes in trends have been stated by several authors throughout the world, with different developments observed depending on the continent. Following a period of approximately 40Â days of almost continuous rain that occurred from October to November 2019 across the Italian territory and caused several hazards (e.g., floods and landslides), a relevant question for decision-makers and civil protection actors emerged regarding the relative frequencies of given rainfall events in the Warning Hazard Zones (WHZs) of Italy. The derived products of this work could answer this question for both weather and hydrogeological operators thanks to the frequency and spatio-temporal distribution analyses conducted on 10-year daily rainfall data over the entire Italian territory. This work aspires to be an additional tool used to analyse events that have occurred, providing further information for a better understanding of the probability of occurrence and distribution of future events
Current nanocarrier strategies improve vitamin B12 pharmacokinetics, ameliorate patients’ lives, and reduce costs
Vitamin B12 (VitB12) is a naturally occurring compound produced by microorganisms and an essential nutrient for humans. Several papers highlight the role of VitB12 deficiency in bone and heart health, depression, memory performance, fertility, embryo development, and cancer, while VitB12 treatment is crucial for survival in inborn errors of VitB12 metabolism. VitB12 is administrated through intramuscular injection, thus impacting the patients’ lifestyle, although it is known that oral administration may meet the specific requirement even in the case of malabsorption. Furthermore, the high-dose injection of VitB12 does not ensure a constant dosage, while the oral route allows only 1.2% of the vitamin to be absorbed in human beings. Nanocarriers are promising nanotechnology that can enable therapies to be improved, reducing side effects. Today, nanocarrier strategies applied at VitB12 delivery are at the initial phase and aim to simplify administration, reduce costs, improve pharmacokinetics, and ameliorate the quality of patients’ lives. The safety of nanotechnologies is still under investigation and few treatments involving nanocarriers have been approved, so far. Here, we highlight the role of VitB12 in human metabolism and diseases, and the issues linked to its molecule properties, and discuss how nanocarriers can improve the therapy and supplementation of the vitamin and reduce possible side effects and limits
Atomic force microscopy techniques for nanomechanical characterization : a polymer case study
Atomic force microscopy (AFM) is a versatile tool to perform mechanical
characterization of surface samples at the nanoscale. In this work, we review
two of such methods, namely contact resonance AFM (CR-AFM) and torsional
harmonics AFM (TH-AFM). First, such techniques are illustrated and their
applicability on materials with elastic moduli in different ranges are discussed,
together with their main advantages and limitations. Then, a case
study is presented in which we report the mechanical characterization using
both CR-AFM and TH-AFM of polyaniline and polyaniniline doped with
nanodiamond particles tablets prepared by a pressing process. We determined
the indentation modulus values of their surfaces, which were found in fairly
good agreement, thus demonstrating the accuracy of the techniques. Finally,
the determined surface elastic moduli have been compared with the bulk ones
measured through standard indentation testing.
INTRODUCTION
In the field of nanotechnology, the development of
innovative and nondestructive characterization
techniques plays a crucial role. Indeed, the characterization
of nanostructured hybrid materials (e.g.,
thin films and nanocomposites) and devices requires
the capability of acquiring maps of the local mechanical
properties at the nanoscale. Nanoindentation
is the most common method for determining the
mechanical properties of thin films. However, its
applicability is strictly limited by the thickness of
the sample. Furthermore, its poor spatial resolution
does not allow the reconstruction of an accurate
distribution of the sample surface mechanical
properties. For this reason, alternative methods,
based on atomic force microscopy (AFM), have been
developed. By exploiting the high resolution of the
AFM, maps of the surface mechanical properties
(i.e., indentation modulus) can be achieved. Among
these techniques, AFM nanoindentation1 is the
simplest method used to evaluate the local mechanical
properties o
Energy loss measurement for charged particles in very thin silicon layers
The energy loss distribution f(D) of highly relativistic charged particles has been measured for thin silicon layers with thickness ranging from 5.6 to 120 mm. In this work, using an innovative method, the dependence of the energy loss distribution from the thickness of the silicon absorber has been investigated in great detail with reference to CMOS Active Pixel Sensors. The measured energy loss distributions are well-reproduced by calculations also when the target electrons binding energy is taken into account. Finally the results obtained with this method are compared with existing experimental results and theoretical data
Testosterone Enanthate: An In Vitro Study of the Effects Triggered in MG-63 Cells
The aim of this study was to investigate the effects of the androgenic hormone testosterone enanthate (TE) on human MG-63 cells. MG-63 were cultured for 24 h in the presence of TE at increasing concentrations to assess its lethal dose. Therefore, the suitable concentration for a prolonged use of TE in vitro was assessed by viability assay over 9 days. Finally, MG-63 were exposed to TE for 14 days and assayed for differentiation by qPCR and Alizarin Red S staining. TE in the amount of 100 µM resulted as the maximum dose tolerated by MG-63 cells after 24 h. However, a prolonged exposure in culture TE in the amount of 100 µM showed a cytostatic effect on cell proliferation. On the contrary, TE 10 µM was tolerated by the cells and did not boost cell proliferation, but did enhance new bone formation, as revealed by COL1A1, ALPL, BGLAP, and IBSP gene expression after 3, 7, and 14 days, and calcium deposition by Alizarin Red S staining after 14 days. Based on the current study, 10 µM is the critical dose of TE that should be used in vitro to support bone differentiation of MG-63 cells
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