1,721,570 research outputs found
Individual optimal frequency in whole-body vibration. Effect of protocol, joint angle, and fatiguing exercise
No full textCarlucci, F, Felici, F, Piccinini, A, Haxhi, J, and Sacchetti, M. Individual optimal frequency in whole-body vibration: effect of protocol, joint angle, and fatiguing exercise. J Strength Cond Res 30(12): 3503-3511, 2016-Recent studies have shown the importance of individualizing the vibration intervention to produce greater effects on the neuromuscular system in less time. The purpose of this study was to assess the individual optimal vibration frequency (OVF) corresponding to the highest muscle activation (RMSmax) during vibration at different frequencies, comparing different protocols. Twenty-nine university students underwent 3 continuous (C) and 2 random (R) different vibrating protocols, maintaining a squat position on a vibration platform. The C protocol lasted 50 seconds and involved the succession of ascending frequencies from 20 to 55 Hz, every 5 seconds. The same protocol was performed twice, having the knee angle at 120° (C) and 90° (C90), to assess the effect of joint angle and after a fatiguing squatting exercise (CF) to evaluate the influence of fatigue on OVF assessment. In the random protocols, vibration time was 20 seconds with a 2-minute (R2) and a 4-minute (R4) pauses between tested frequencies. Muscle activation and OVF values did not differ significantly in the C, R2, and R4 protocols. RMSmax was higher in C90 (p < 0.001) and in CF (p = 0.04) compared with the C protocol. Joint angle and fatiguing exercise had no effect on OVF. In conclusion, the shorter C protocol produced similar myoelectrical activity in the R2 and the R4 protocols, and therefore, it could be equally valid in identifying the OVF with considerable time efficiency. Knee joint angle and fatiguing exercise had an effect on surface electromyography response during vibration but did not affect OVF identification significantly
A Methodological Update Proposal for Measuring the Degree of Periphery from Essential Services in the Classification of Inner Areas in Italy|Propuesta de actualización metodológica para la medición del grado de periferia desde los servicios esenciales en la clasificación de las Áreas Internas en Italia
No full textIn February 2022, the Interministerial Committee for Economic Planning and Sustainable Development announced the update of the Italian Inner Areas map. In this update, the analysis tools were revised, returning more precise results, but both indicators and methodology did not change. This paper intends to present part of the key points of ongoing research that analyses the current methods and criteria for classifying Inner Areas. To develop a homogeneous territorial mapping tool, better suited to the purposes of territorial cohesion, the objective of the research is to define a new method of classification. The actual definition of Inner Areas corresponds with the "fragile territories" where the overall condition of difficulty is one of Italy's greatest criticalities. However, it would be a mistake to consider them as "weak". The current classification distorts the reading of the territory simplifying social, economic, and environmental reading. Furthermore, it ignores essential services embedded in fundamental contexts. The main strategy proposes a new perspective no longer based on dependence on urban poles but on the distribution of resources. This article demonstrates the possibility of an update of the techniques for measuring accessibility to essential services by comparing the results of the current classification with the updated method, based on temporal isochrones, which considers the actual distribution of the population and of individual essential services
Pro-competitive reforms and timing of implementation: an Igem-based simulation analysis for Italy
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Frammenti antigenici di Toxoplasma gondii, metodo per il loro ottenimento, loro uso in kit diagnostici e per la preparazione di vaccini
No full textA New Approach to the Scoreboard
No full textPurpose – The purpose of this paper is to investigate the information content of the variables that can
help detecting external and internal imbalances in an early stage. The starting point is the Scoreboard,
where nine indicators are chosen in order to increase macroeconomic surveillance of all member states.
Design/methodology/approach – This paper provides an overview of the variables that could
be informative for imbalances by focusing on EU-27 countries over the period 1960-2010. The number
of chosen variables is 28, and they are aggregated in six macro-areas. Therefore, once an imbalance
is observed in any of those areas, it is possible to detect in a simple way which specific variable
is determining such outcome.
Findings – In general, this approach provides reliable signal to the policy-makers about the indicators
that can drive imbalances within the area, shedding light on the relationship among the variables
included in the analysis, too.
Research limitations/implications – In fact, the empirical results underline some well-known
critical issue for several countries, and is largely in line with results obtained in a variety of EC and
OECD studies.
Originality/value – The main added value of the approach adopted in this paper is the introduction
of more variables than those initially proposed by the European Commission in the construction of the
Scoreboard. This provides more information about the macroeconomic situation in each country,
preserving, however, the simplicity of the analysis as the variables are aggregated by homogeneous areas
New capture molecules (probes) for protein chips
No full textThis review book, without pretending of being exhaustive, will focus on protein and peptide arrays highlighting their technical challenges and presenting new directions by means of a set of selected recent applications. It has been structured in three main chapters that treat the single basic themes of applications, types and realization of protein chips, to face the matter with a multidisciplinary approach involving: biology for capture molecules, chemistry for methods of immobilization, material engineering for support fabrication, physics for detection systems. In recent years, protein microarrays have become one of the most invaluable research tools in the field of large-scale and high-throughput biology, and their use in basic research, diagnostics and drug discovery has emerged as a great promise of medicine. The fast growth of protein chip technology is fuelled by the continuous growth of genomic information; the integration of large datasets from different approaches will result in the generation of a huge network and deepen our understanding of the molecular mechanisms of life. The actual impact of the new technology on proteomic and medical research are yet to be fully realized, opening a new era of collection and analysis information. During the last few decades, scientists have extended their investigations beyond molecular level into the field of the so-called “supramolecular chemistry”. Basic themes such as molecular self-assembly, folding, molecular recognition, host-guest chemistry, and nanoscience are often associated with this area of research. Broadly speaking, supramolecular chemistry is the study of interactions between, rather than within, molecules. While traditional chemistry focuses on strong association forces such as covalent and ionic bonds (used to assemble atoms into discrete molecules), supramolecular chemistry examines the weaker and reversible noncovalent interactions between molecules (used to organize and hold together supramolecular assemblies), including hydrogen bonding, metal coordination, hydrophobic forces, van der Waals forces, hydrophilic-hydrophobic interactions and electrostatic effects. In nature, organization on the nanometer scale is crucial for the remarkable properties and functional capabilities of biological systems; thus, the use of these principles led to an increasing understanding of many biological processes based on protein structure and function. Concomitantly, nanotechnologists began to be able to take these concepts and apply them to synthetic systems based on noncovalent interactions. The development of selective “host-guest” complexes in particular, in which a host molecule recognizes and selectively binds a certain guest, can be cited as an important contribution to protein chip technology. In addition, the need for improved miniaturization and device performance in the microelectronics industry has inspired many investigations into supramolecular chemistry. It is conceivable that “bottom up” materials fabrication approaches based on supramolecular chemistry will provide a solution to the anticipated size limitations of “top down” approaches, such as photolithography, thereby providing the means to fabricate ultrasmall electronic components. Hybrid devices integrate the outstanding electronic and photonic properties of nonmolecular hard materials such as silicon to the excellent bio-recognition, chemical sensing, and related properties of designed, soft molecular materials to yield structures capable of performing disease diagnosis, environmental monitoring, controlled drug delivery, and so on. Miniaturized and parallel assay systems, in particular microarray-based analyses, allow fast, easy and parallel detection of thousands of addressable elements in a single experiment. They are applied to analyse antibody-antigen, protein-protein, protein-nucleic acid, protein-lipid and protein-small molecule as well as enzyme-substrate interactions. New trends in protein chip technology include surface chemistry, capture molecules, labeling and detection methods, high-throughput protein production, and applications to analyse entire proteomes. The challenges are to elucidate the basic cellular events mediating complex processes and those causing diseases. It is well recognised that the complexity of the proteome far exceeds that of the genome. When variables such as alternative gene splicing events, post-translational modifications and individual coding variants are taken into account, the number of different molecular protein species is likely to be at least 1-2 orders of magnitude greater than the number of genes. Conventional proteome analysis by 2D gel electrophoresis and mass spectrometry, while highly effective, has limitations and in particular may miss many proteins of interest when expressed at low abundance and is unsuited to diagnostic applications. Since the little abundant proteins are often those of the greatest diagnostic interest (e.g. cytokines and biomarkers in plasma), there is therefore an acknowledged need for other highly sensitive, specific and accessible high throughput technologies for protein detection, quantization and differential expression analysis in health and disease. For this reason, protein arrays are poised to become a central technology at the research and biotechnology levels. Protein arrays generally fall into three types. In protein function arrays, a large set of purified proteins or peptides or even an entire proteome is spotted and immobilized, then the array is used for parallel screening of a range of biochemical interactions. Protein function arrays are generally aimed at discovering protein function in fundamental research and can be used to study the effect of substrates or inhibitors on enzyme activities, protein-drug or hormone-effector interactions, or epitope mapping. In protein detection microarrays (usually referred as analytical microarrays), an array of affinity reagents (antigens or antibodies, but also peptides or aptamers), rather than the native proteins themselves, is immobilized on a support and used to determine protein abundances in a complex matrix such as plasma/serum or tissue extracts. Analytical arrays can be used to assay antibodies (for diagnosis of allergy or autoimmunity diseases) or to monitor protein expression on a large scale. In a third category of protein arrays (usually referred as reverse phase microarrays), tissues, cell lysates, or serum samples are spotted on the surface and probed with one antibody per analyte for a multiplex readout. For construction of arrays, sources of proteins include cell-based expression systems for recombinant proteins, purification from natural sources, production in vitro by cell-free translation systems, and synthetic methods for peptides. Many of these methods can be automated for high throughput production. Recent advances involve the use of whole phage as selective and specific probes, possessing distinct advantages as durability, stability, standardization and low-cost production. For capture arrays and protein function analysis, it is clearly important that proteins should be correctly folded and functional. On the other hand, arrays of denatured proteins are useful in screening antibodies for cross-reactivity, identifying auto-antibodies and selecting ligand binding proteins, where linear epitopes are recognised. The immobilisation method used should be reproducible, applicable to proteins of different properties (size, hydrophilic, hydrophobic), amenable to high throughput and automation, and compatible with retention of fully functional protein activity. Both covalent and noncovalent methods of protein immobilisation are used with various pros and cons. What is required from any method is optimal sensitivity and specificity, with low background to give high signal to noise. Protein analytes binding to antibody arrays may be detected directly or via a secondary antibody in a sandwich assay. Direct labelling is used for comparison of different samples with different fluorophores. Where pairs of antibodies directed at the same protein ligand are available, sandwich immunoassays provide high specificity and sensitivity and are therefore the method of choice for low abundance proteins such as cytokines; they also give the possibility of detection of protein modifications. On the other hand, label-free detection methods, including Mass Spectrometry and Surface Plasmon Resonance, avoid alteration of ligand. The design of capture arrays, particularly when exposed to heterologous mixtures such as plasma and tissue extracts, needs to take into consideration the problems of cross-reactivity which will occur particularly with highly multiplexed assays. Antibodies can be surprisingly cross-reactive, which in the high throughput microarray field can render results misleading or, at worst, useless. Successful multianalyte analysis will therefore require careful screening of each polyclonal antiserum, hybridoma or recombinant clone for cross-reactions against all antigens on the array. The use of combinations of antibodies against individual targets in sandwich assays should help to minimize cross-reactions, or the linkage to mass spectrometry to confirm the identity of bound ligands. As diagnostic devices, microarrays exploit the power of multiplexing simultaneous analyses of different samples and repeated analyses of the same samples in automated way. Diagnostics formats include arrays of antibodies, as in detection of cytokines, and antigens to detect serum antibodies in screens for infections, autoimmune diseases and allergies. Highly parallel analysis on arrays will allow determination of tumour markers in extracts with only a minimum of biopsy material, creating new possibilities for monitoring cancer treatment and therapy. Discovery of new autoantibody specificities is possible by screening patient sera against arrays of human proteins. The quantitative detection of proteins in cells and tissues and comparison in different conditions (health, disease, differentiation, drug treatment, etc) is a central aim of proteomics. The array format is well established for the rapid, global analysis of nucleic acids, as in the use of oligonucleotide and cDNA arrays for gene expression (transcription) profiling. Two-dimensional gel electrophoresis technology, on which most proteome profiling is based currently, is also limited in various ways, particularly, as stated above, in the difficulty of finding and quantitatively estimating low abundance proteins. For information about the expression of the proteome, protein and peptide arrays are becoming major tools, and the information that will be obtained from them in the future will complement transcriptional data. Capture arrays sensitively and accurately detect low levels of proteins with minimal technical know-how on the part of the user, and we can expect them to be used widely to measure differential protein expression. They will provide a powerful and reliable platform for extending molecular analysis beyond the limitations of DNA chips. On the other hand, it is difficult to store large-scale protein arrays in a functional state for long periods of time, due to the sensitivity and heterogeneity of proteins, unlike DNA that is a highly stable molecule capable of long-term storage. Therefore, an interesting concept nowadays is to make protein arrays directly from DNA, either co-distributed or pre-arrayed, using cell free protein expression systems, to create the proteins on the arrays on demand as and when required. Thus, in situ methods address the three main issues in protein array technology: efficient global protein expression and availability; functional protein immobilization and purification, and on-chip stability over time. The stability and lifetime of protein arrays in different formats needs to be considered. Detection methods are another important consideration, with requirements of sensitivity, accuracy and quantization over a wide range. The design of the array will be influenced by the readout system. Finally, standardization is an issue common to all high throughput technologies: the existence and development of many alternative formats and conditions inevitably leads to problems in comparison of results. Standards for protein arrays and a framework for their implementation will need to be established at an international level
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