Research Scientists In Different Areas Research Articles

Metrology and Nanometrology at Agricultural/Food/Nutraceutical Interface: An Updated Shot

Abstract: Nanometrology has been considered as a key to the future of nanotechnology since recently. It is particularly important for nanoparticle market development that is commonly applied in dif-ferent areas of science. The adoption of nanotechnologies in food and agrochemical industries represents a new frontier, with particular regard to plant defence against pathogen agents. Na-nometrology deals with a broad range of measurements, as well as chemical and structural characterization, electronic, thermal, and mechanical properties, fabrication and monitoring of nanodevices, and theoretical modelling of nanomaterials properties. Besides the scientific and technological values of a global standard offered by nanometrology, there are also several in-dustry-related values. In this paper, the most common the areas of science emphasized on the most frequently applied methods by the example of techniques/tools that have been described from a metrological standpoint at a nano size scale. Therefore, at the microscopic scale may be widely applied: optical techniques, for example, X-ray Photoelectron Spectroscopy (XPS), or op-tical transmission. Moreover, Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDX) can be used for microscopic characterization, while Scanning Probe Micros-copy (SPM), consisting of Scanning-Tunnelling Microscopy (STM) and Atomic Force Microscopy (AFM), as well as Transmission-Electron Microscopy (TEM), can be employed at the nanoscopic scale. The review has also mentioned about Secondary Ion Mass Spectroscopy (SIMS) to analyze secondary ions using a mass spectrometer. In addition, Electron Energy Loss Spectroscopy (EELS) using high-energy electrons from sample penetration or Fourier Transform Infrared Spectroscopy (FTIR) to obtain the infrared spectrum of a sample were also presented. Particle size analysis can be analyzed by performing Small-/Wide-Angle X-ray Scattering (SAXS/WAXS) and Dynamic Light Scattering (DLS) techniques. A specific metrology approach is required for most nanoparticle-based products, that is, the way nanometrology is significant for production quality control and for toxicology studies. This review wants to give an updated shot on the metrological approaches and applications, with particular attention to nanometrology for dif-ferent areas of scientific research, i.e., food, agricultural, nutraceutical, biological and medical ones. The novelty character of this paper is to discuss the application of nanotechnologies under metrological principles and approach at the interface of different integrated, multipurpose and multidisciplinary application fields. The following topics are here explored: i) metrology: defi-nitions, principles, and main features; ii) calibration methods and techniques; iii) measurement methods and systems; iv) proficiency testing; v) nanometrology. Particularly, nanometrology was highlighted in the following directions: significance of the nanodimension, nanometrology in chemical research, nanometrology for the characterization of nanoparticles, nanometrology in biological and medical sciences, mechanical nanometrology, electrical nanometrology and applications of nanometrology in agriculture and food industry.

Spectral Similarity Measures for In Vivo Human Tissue Discrimination Based on Hyperspectral Imaging.

Similarity measures are widely used as an approved method for spectral discrimination or identification with their applications in different areas of scientific research. Even though a range of works have been presented, only a few showed slightly promising results for human tissue, and these were mostly focused on pathological and non-pathological tissue classification. In this work, several spectral similarity measures on hyperspectral (HS) images of in vivo human tissue were evaluated for tissue discrimination purposes. Moreover, we introduced two new hybrid spectral measures, called SID-JM-TAN(SAM) and SID-JM-TAN(SCA). We analyzed spectral signatures obtained from 13 different human tissue types and two different materials (gauze, instruments), collected from HS images of 100 patients during surgeries. The quantitative results showed the reliable performance of the different similarity measures and the proposed hybrid measures for tissue discrimination purposes. The latter produced higher discrimination values, up to 6.7 times more than the classical spectral similarity measures. Moreover, an application of the similarity measures was presented to support the annotations of the HS images. We showed that the automatic checking of tissue-annotated thyroid and colon tissues was successful in 73% and 60% of the total spectra, respectively. The hybrid measures showed the highest performance. Furthermore, the automatic labeling of wrongly annotated tissues was similar for all measures, with an accuracy of up to 90%. In future work, the proposed spectral similarity measures will be integrated with tools to support physicians in annotations and tissue labeling of HS images.

Application of physics-informed neural network in the analysis of hydrodynamic lubrication

The last decade has witnessed a surge of interest in artificial neural network in many different areas of scientific research. Despite the rapid expansion in the application of neural networks, few efforts have been carried out to introduce such a powerful tool into lubrication studies. Thus, this work aims to apply the physics-informed neural network (PINN) to the hydrodynamic lubrication analysis. The 2D Reynolds equation is solved. The PINN is a meshless method and does not require big data for network training compared with classical methods. Our results are consistent with those obtained by experiments and the finite element method. Hence, we envision that the PINN method will have great application potential in lubrication and bearing research.

Still no Rest for the Reductases: Ribonucleotide Reductase (RNR) Structure and Function: An Update.

Herein we present a multidisciplinary discussion of ribonucleotide reductase (RNR), the essential enzyme uniquely responsible for conversion of ribonucleotides to deoxyribonucleotides. This chapter primarily presents an overview of this multifaceted and complex enzyme, covering RNR's role in enzymology, biochemistry, medicinal chemistry, and cell biology. It further focuses on RNR from mammals, whose interesting and often conflicting roles in health and disease are coming more into focus. We present pitfalls that we think have not always been dealt with by researchers in each area and further seek to unite some of the field-specific observations surrounding this enzyme. Our work is thus not intended to cover any one topic in extreme detail, but rather give what we consider to be the necessary broad grounding to understand this critical enzyme holistically. Although this is an approach we have advocated in many different areas of scientific research, there is arguably no other single enzyme that embodies the need for such broad study than RNR. Thus, we submit that RNR itself is a paradigm of interdisciplinary research that is of interest from the perspective of the generalist and the specialist alike. We hope that the discussions herein will thus be helpful to not only those wanting to tackle RNR-specific problems, but also those working on similar interdisciplinary projects centering around other enzymes.

Transformation of pedagogical conditions into factors in the development of initiative in the work collective

Introduction.The problem of determining the pedagogical conditions and factors, as well as their correlation for the formation of initiative among the stuff is one of the urgent directions in the modern approach to personnel management. This issue is relevant in the possibility of applying it to the development of the initiative among the staff members.Materials and Methods. The main methods were the analysis of literature on the problem under study from different areas of scientific research, scientific articles on the topic of research, as well as generalization and systematization of the data obtained. The analysis of the relationship and interconnections of these concepts is carried out.Results.A comparative analysis of the terms "condition" and "factor" in various fields of knowledge has been carried out. It was found that there is no clear division between the concepts; in many studies, these concepts are identical. At the same time, differences were identified in the definitions of these concepts in philosophy, pedagogy and psychology. In the context of the problem of the formation of initiative in the work collective, it was determined that conditions and factors can transform into each other. A visual scheme was proposed for transforming conditions into factors through the assessment procedure and conscious actions to change conditions. A visual scheme was proposed for transforming conditions into factors through the assessment procedure and conscious actions to change conditions. The question of the specifics of the relationships between the concepts of conditions and factors, as applied to a specific team, remains open. The latter result means that it is necessary to conduct research in a specific work collective working for specific purposes.Discussions and Conclusions.The paper presents conclusions about the differences between the terms "condition" and "factors", presents the relationship of these concepts, conclusions about the possible mechanisms for the transition from one concept to another in the study of the development of initiative in the work collective, the dynamics of transformation of conditions into factors of successful pedagogical activity, as well as , a consolidated form of control of the dynamics of changes in specific conditions, important for the formation of initiative in the work collective, and their transformation into factors is proposed. As a result, a variant of the classification of the conditions for the development of initiative in the work collective is presented.

Discovering Correlation Indices for Link Prediction Using Differential Evolution

Binary correlation indices are crucial for forecasting and modelling tasks in different areas of scientific research. The setting of sound binary correlations and similarity measures is a long and mostly empirical interactive process, in which researchers start from experimental correlations in one domain, which usually prove to be effective in other similar fields, and then progressively evaluate and modify those correlations to adapt their predictive power to the specific characteristics of the domain under examination. In the research of prediction of links on complex networks, it has been found that no single correlation index can always obtain excellent results, even in similar domains. The research of domain-specific correlation indices or the adaptation of known ones is therefore a problem of critical concern. This paper presents a solution to the problem of setting new binary correlation indices that achieve efficient performances on specific network domains. The proposed solution is based on Differential Evolution, evolving the coefficient vectors of meta-correlations, structures that describe classes of binary similarity indices and subsume the most known correlation indices for link prediction. Experiments show that the proposed evolutionary approach always results in improved performances, and in some cases significantly enhanced, compared to the best correlation indices available in the link prediction literature, effectively exploring the correlation space and exploiting its self-adaptability to the given domain to improve over generations.

On a Minimum Distance Procedure for Threshold Selection in Tail Analysis

Power-law distributions have been widely observed in different areas of scientific research. Practical estimation issues include how to select a threshold above which observations follow a power-law distribution and then how to estimate the power-law tail index. A minimum distance selection procedure (MDSP) is proposed in Clauset et al. (2009) and has been widely adopted in practice, especially in the analyses of social networks. However, theoretical justifications for this selection procedure remain scant. In this paper, we study the asymptotic behavior of the selected threshold and the corresponding power-law index given by the MDSP. We find that the MDSP tends to choose too high a threshold level and leads to Hill estimates with large variances and root mean squared errors for simulated data with Pareto-like tails.

New initiatives for Brazilian aquatic plant data management

ABSTRACT Initiatives directed at managing information on aquatic plants can support different areas of scientific research, educational practices and political decisions for sustainable management and protection of wetlands and natural resources, as well as reveal knowledge gaps regarding aquatic plants and wetlands. Furthermore, such initiatives can contribute directly to consolidating wetland classification systems in Brazil. The objectives of this work are to present and explore the use of a data repository and online platform created specifically for the management of data on aquatic plants in Brazil. The data repository for aquatic plants was developed to store information on species occurrence records in a standardized form considering: systematics, taxonomy, habit, life form, geographic distribution, hydrographic basin, wetland, bibliographic references and herbarium material. A total of 3,903 records referring to the Southeast Region of Brazil were generated for the data repository. This total encompassed 1,036 species distributed among 132 families and 466 genera. Our results illustrate the diversity of information available regarding aquatic plants, circumscribe this group of species and serve as a source of data about them. Similar databases and electronic infrastructures can be developed for other flora in the future.

Classification and reporting of severity experienced by animals used in scientific procedures: FELASA/ECLAM/ESLAV Working Group report.

Directive 2010/63/EU introduced requirements for the classification of the severity of procedures to be applied during the project authorisation process to use animals in scientific procedures and also to report actual severity experienced by each animal used in such procedures. These requirements offer opportunities during the design, conduct and reporting of procedures to consider the adverse effects of procedures and how these can be reduced to minimize the welfare consequences for the animals. Better recording and reporting of adverse effects should also help in highlighting priorities for refinement of future similar procedures and benchmarking good practice. Reporting of actual severity should help inform the public of the relative severity of different areas of scientific research and, over time, may show trends regarding refinement. Consistency of assignment of severity categories across Member States is a key requirement, particularly if re-use is considered, or the safeguard clause is to be invoked. The examples of severity classification given in Annex VIII are limited in number, and have little descriptive power to aid assignment. Additionally, the examples given often relate to the procedure and do not attempt to assess the outcome, such as adverse effects that may occur. The aim of this report is to deliver guidance on the assignment of severity, both prospectively and at the end of a procedure. A number of animal models, in current use, have been used to illustrate the severity assessment process from inception of the project, through monitoring during the course of the procedure to the final assessment of actual severity at the end of the procedure (Appendix 1).

Synthetic Loads Analysis of Directed Acyclic Graphs for Scheduling Tasks

Graphs are structures used in different areas of scientific research, for the ease they have to represent different models of real life. There is a great variety of algorithms that build graphs with very dissimilar characteristics and types that model the relationships between the objects of the problem to solve. To model the relationships, characteristics such as depth, width and density of the graph are used in the directed acyclic graphs (DAGs) to find the solution to the objective problem. These characteristics are rarely analyzed and taken into account before being used in the approach of a solution. In this work, we present a set of methods for the random generation of DAGs. DAGs are produced with three of these methods representing three synthetic loads. Each of the three above characteristics is evaluated and analyzed in each of DAGs. The generation and evaluation of synthetic loads is with the objective of predicting the behavior of each DAG, based on its characteristics, in a scheduling algorithm and assignment of parallel tasks in a distributed heterogeneous computing system (DHCS).

Powerful qPCR assays for the early detection of latent invaders: interdisciplinary approaches in clinical cancer research and plant pathology.

Latent invaders represent the first step of disease before symptoms occur in the host. Based on recent findings, tumors are considered to be ecosystems in which cancer cells act as invasive species that interact with the native host cell species. Analogously, in plants latent fungal pathogens coevolve within symptomless host tissues. For these reasons, similar detection approaches can be used for an early diagnosis of the invasion process in both plants and humans to prevent or reduce the spread of the disease. Molecular tools based on the evaluation of nucleic acids have been developed for the specific, rapid, and early detection of human diseases. During the last decades, these techniques to assess and quantify the proliferation of latent invaders in host cells have been transferred from the medical field to different areas of scientific research, such as plant pathology. An improvement in molecular biology protocols (especially referring to qPCR assays) specifically designed and optimized for detection in host plants is therefore advisable. This work is a cross-disciplinary review discussing the use of a methodological approach that is employed within both medical and plant sciences. It provides an overview of the principal qPCR tools for the detection of latent invaders, focusing on comparisons between clinical cancer research and plant pathology, and recent advances in the early detection of latent invaders to improve prevention and control strategies.

Lens-based fluorescence nanoscopy.

The majority of studies of the living cell rely on capturing images using fluorescence microscopy. Unfortunately, for centuries, diffraction of light was limiting the spatial resolution in the optical microscope: structural and molecular details much finer than about half the wavelength of visible light (~200nm) could not be visualized, imposing significant limitations on this otherwise so promising method. The surpassing of this resolution limit in far-field microscopy is currently one of the most momentous developments for studying the living cell, as the move from microscopy to super-resolution microscopy or 'nanoscopy' offers opportunities to study problems in biophysical and biomedical research at a new level of detail. This review describes the principles and modalities of present fluorescence nanoscopes, as well as their potential for biophysical and cellular experiments. All the existing nanoscopy variants separate neighboring features by transiently preparing their fluorescent molecules in states of different emission characteristics in order to make the features discernible. Usually these are fluorescent 'on' and 'off' states causing the adjacent molecules to emit sequentially in time. Each of the variants can in principle reach molecular spatial resolution and has its own advantages and disadvantages. Some require specific transitions and states that can be found only in certain fluorophore subfamilies, such as photoswitchable fluorophores, while other variants can be realized with standard fluorescent labels. Similar to conventional far-field microscopy, nanoscopy can be utilized for dynamical, multi-color and three-dimensional imaging of fixed and live cells, tissues or organisms. Lens-based fluorescence nanoscopy is poised for a high impact on future developments in the life sciences, with the potential to help solve long-standing quests in different areas of scientific research.

Variable selection usingLqpenalties

High‐dimensional data analysis emerges in many different areas of scientific research and social practice. Variable selection is an important task in statistical analysis for high‐dimensional data. The traditional all‐subset‐selection method can be ideal for variable selection, but it is computationally intractable in the high‐dimensional setting. In both regression and classification contexts, sparsity penalties are commonly used for the purpose of defining the complexity of the resulting model so as to achieve variable selection. The current article reviews a few important milestones and some recent works in the area of variable selection, especially those methods which useLqnorm and their variants as the penalty term. In particular, we review theLqpenalty, nonconvex penalties, among others. In ultrahigh‐dimensional data analysis, independence learning is often used for the purpose of dimension reduction. Theoretical results, methodological developments and computational innovations in regard to these methods are discussed. These variable selection techniques can be easily extended to problems beyond linear regression, such as classification, quantile regression, etc. Lastly, an interesting and promising research trend is the combination of multiple methods and we review several successful methods which fall into this category.This article is categorized under:Statistical and Graphical Methods of Data Analysis > Modeling Methods and AlgorithmsStatistical Models > Model SelectionStatistical Models > Linear Models

Immunophenotyping of Classic Murine Myeloma Cell Lines Used for Monoclonal Antibody Production

Murine myeloma cell lines play an important role in different areas of scientific research and are essential tools for monoclonal antibody production technology. Thus, it is important to understand the biology of these cell lines in order to provide useful information to various research fronts. The present study aims to perform detailed analyses of surface antigens expressed on three major murine myeloma cell lines extensively used for MAb production. The P3X63Ag8.653 cell line expresses molecules associated with T cell interaction (CD40(low), CD80(low)), as well as antigens related to plasma cell phenotype (CD138(high), CD184(low)). The Sp2/0-Ag14 cell line presents molecules associated with BCR activation and regulation (CD79b(low), CD22(low), CD72(med)), molecules related to T cell interaction (CD40(low), CD80(low)), and markers of plasma cell phenotype (CD138(high), CD184(low)). The NS1 cell line presents all molecules of plasma cell phenotype evaluated in this study (CD184(low), CD138(high), CD38(med)) with low expression of CD72 (CD72(low)), a molecule related to BCR activation. Molecules associated with immune response modulation such as CD23 and CD25, as well as CD117, a marker related to undifferentiated cell phenotype, were not observed in any of the three murine myeloma cell lines evaluated. These data show that in spite of their common origin and function, the immunological profiles differ between P3X63Ag8.653, Sp2/0-Ag14, and NS1 cell lines.

EU research activities in alternative testing strategies: current status and future perspectives

Alternative testing methods have become increasingly important within EU funding policy. The driving force behind this push for alternative testing methods is the urgent need for effective and robust alternative toxicity tests in order to make the tools available that are necessary to comply with the 3R-strategy (Replacement, Reduction, Refinement) that has been built into the European Cosmetic (Directive 2003/15/EC) and Chemical (REACH) (Regulation EC No 1907/2006) legislations. Indeed, a general European policy has to take into consideration the growing ethical concern of the public with respect to the use of experimental animals in the risk assessment process of consumer products. It is reasonable to believe that further development and strategic incorporation of recent progress in different areas of scientific research could lead to a better and more mechanistically based approach of studying toxicological problems. In line with this, the pharmaceutical industry is confronted with unexpected failures during the drug development process, even late during the clinical phase. These could not be properly anticipated. Reasons are in particular safety (hepatoand cardiotoxicity) as well clinical efficacy of the new chemical entities. Therefore, incorporation of novel alternative methods, human based and metabolically functional, is high on the priority list since the competitiveness of the European pharmaceutical industry is at stake. An overview of the different EU initiatives in the context of the 3Rs funded research is given in EUR22846 (European Commission 2008) and in the update EUR23886 (European Commission 2009). The EU offers four different funding schemes: (1) Collaborative/Integrated projects, which are medium/large-sized ambitious projects, usually involving several areas of expertise, (2) Specific Targeted Research Projects (STREP), representing smaller networks focussed on specific research issues, (3) SME-STREP, aimed at supporting research of smalland medium-sized enterprises (SMEs), and (4) Specific Support Actions (SSA), for scientific training of personal as well as organization of conferences, workshops and expert meetings (EUR22846, EUR23886). The research networks fall into the categories of high-throughput techniques, specific toxicity tests and organization of forums and workshops. T. Vanhaecke (&) S. Snykers V. Rogiers Department of Toxicology, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium e-mail: tamara.vanhaecke@vub.ac.be

Artificial reproduction technologies (RTs) – all the way to the artificial womb?

In this paper, I argue that the development of an artificial womb is already well on its way. By putting together pieces of information arising from new scientific advances in different areas, (neo-natal care, gynecology, embryology, the human genome project and computer science), I delineate a distinctive picture, which clearly suggests that the artificial womb may become a reality sooner than we may think. Currently, there is a huge gap between the first stages of gestation (using in vitro fertilization) and the 22nd week (inside the womb). At the present time this gap seems an insurmountable barrier for fully developing a fetus outside a natural womb - a notion better known as ectogenesis. The history of science however, suggests that impenetrable barriers are such only temporarily. It is just a matter of time (and due research) until someone - intentionally or by chance - accesses the right answer and finds a way to overcome existing obstacles. Despite misgivings that the case of the artificial womb presents too many barriers, it would be naive to suppose things would happen any differently. I observe in this paper, that it is time to acknowledge the consequences of new developments in different areas of scientific research which are leading to the advent of an artificial womb; and I modestly suggest that we might initiate a discussion on this topic now, while we have still enough time to decide what we may want and why.

Cyberscience and Social Boundaries: The Implications of Laboratory Talk on the Internet

This paper examines the use of an online forum for the discussion of laboratory science. It is argued that such forums are significant in the light of claims made for the impact of information and communications technologies (ICTs) on scientific research, and of broader debates about the role of ICTs in reconfiguring social boundaries. It appears that the impacts of ICTs on scientific research are likely to be diverse and unpredictable, in line with emerging findings in other application domains. In particular, the potential to break down the boundaries between science and lay persons, and between different areas of scientific research, is likely to be limited by the ways in which particular forums are preserved as bounded spaces for specific specialisms. In the case of the forum studied in this paper, discursive practices function to re-establish laboratory boundaries in the online setting. Laboratory talk on the Internet may help to break down barriers between individual laboratories, but is not, in itself, any more accessible to lay people than talk in the private spaces of the laboratory.

A new approach to surveying public opinion on different areas of scientific research

The public's attitude towards different areas of scientific research is an important element in formulating science and technology policy. This paper proposes a new approach to surveying public opinion on specific areas of scientific research. A preliminary study was conducted using this approach that found a difference of opinion between scientists and the public, demonstrating the significance of this kind of survey. Through conducting a regression analysis of the results of the survey, it is concluded that the most suitable way of grasping public opinion is to ask a question about the respondents' wish for the early realization of a scientific objective.

On a Method for Increasing the Resolution of Atmospheric Pressure Measurements

It is known that conventional methods for determining atmospheric pressure by measuring the length-height of the mercury column in Torriceli's Tube (TT) give resolution up to 1 Pa. A method is presented in this note for determining atmospheric pressure by measuring mercury column mass in TT which facilitates measurement with a resolution up to 0.01 Pa; this is approximately 100 times the resolution afforded by conventional methods. The application of this method requires measurement equipment available in a large number of laboratories worldwide, and it may be used in different areas of scientific research, using various measurement techniques and in experimental physics.