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1.
J Agric Food Chem ; 68(34): 9158-9170, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32786874

RESUMO

The main objective of this investigation was to analyze the scientific production in global research on nanotechnology, integrating scientific production, funding of studies, collaborations between countries, and the most cited publications. The source for obtaining the research papers for our analysis was the Science Citation Index Expanded from the Web of Science. A total of 3546 documents were extracted during the period of 1997-2018. Food science & technology, chemistry (applied and analytical), spectroscopy, and agriculture appeared as the main areas where the articles were published. Most prolific and cited journals were Analytical Methods, Journal of Agricultural and Food Chemistry, and Food Chemistry. The co-word analysis showed the relationships between "nanoparticles", which is the central word, and "silver nanoparticles", "delivery systems", and "zinc-nanoparticles". The most productive countries were China (1089 papers), the United States (523), Iran (427), and India (359). The main cited topics deal with the biomedical applications of nanoparticles, its synthesis from plants, and its applications in food science. The results highlight an important collaboration between institutions and countries. The availability of funding for research in nanotechnology was remarkable compared to other fields. The multidisciplinarity of the nanotechnology field is one of the main features as well as one of the central findings.


Assuntos
Pesquisa Biomédica/estatística & dados numéricos , Nanotecnologia/estatística & dados numéricos , Publicações/estatística & dados numéricos , Bibliometria , Pesquisa Biomédica/economia , Pesquisa Biomédica/tendências , Organização do Financiamento/estatística & dados numéricos , Nanopartículas/química , Nanotecnologia/economia , Nanotecnologia/tendências , Estados Unidos
2.
Comput Methods Programs Biomed ; 189: 105324, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32058126

RESUMO

BACKGROUND: Hybrid nanoliquids have several benefits in comparison to orthodox type liquids because of their revised attributes. The enhanced rheological along with thermo-physical attributes, create them additionally apposite for systems featuring solar energy. Thus, in the current analysis, the focus retained to pursue the diversity behave by hybrid nanofluid in comparison with traditional nanofluid considering the scheme of micropolar fluid in the environment of MHD, with rotating porous channel on the exponentially stretched surface. METHODS: For the solution of the generated differential model, a numerical technique BVP-4C is applied. The information extraction is done by the graphical representations of these solutions. RESULTS: The velocity, temperature, and micro-rotation are analyzed deeply under graphical representation. For nanofluid and hybrid nanofluid, we investigated a comprehensive behavior by the variation of skin friction and Nusselt number. As a result of these explorations, we found in depth the higher rate of heat transferring in the scenario of hybrid nanofluid in comparison with nanofluid in the manifestation of porosity and rotation.


Assuntos
Algoritmos , Temperatura Alta , Hidrodinâmica , Magnetismo , Modelos Teóricos , Nanotecnologia , Gráficos por Computador , Nanotecnologia/estatística & dados numéricos , Porosidade
3.
Rev Soc Bras Med Trop ; 52: e20180246, 2019 Apr 11.
Artigo em Português | MEDLINE | ID: mdl-30994800

RESUMO

INTRODUCTION: Leishmaniasis is a global public health concern. Currently available treatments are associated with considerable side effects. The use of nanotechnology has shown promise for improving efficacy and bioavailability and minimizing side effects. METHODS: This study investigated available literature, including patents and scientific articles, to identify advances in the use of nanotechnology for the treatment of leishmaniasis. RESULTS: Our findings revealed a stable number of patents and scientific articles published over the past five years. CONCLUSIONS: There is a need to intensify research on the use of nanotechnology for the treatment of leishmaniasis.


Assuntos
Antiprotozoários/administração & dosagem , Pesquisa Biomédica/estatística & dados numéricos , Leishmaniose/tratamento farmacológico , Nanotecnologia/estatística & dados numéricos , Bibliometria , Humanos , Patentes como Assunto/estatística & dados numéricos
4.
PLoS One ; 14(1): e0210817, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30650151

RESUMO

The study of two- dimensional (2D) materials is a rapidly growing area within nanomaterials research. However, the high equipment costs, which include the processing systems necessary for creating these materials, can be a barrier to entry for some researchers interested in studying these novel materials. Such process systems include those used for chemical vapor deposition, a preferred method for making these materials. To address this challenge, this article presents the first open-source design for an automated chemical vapor deposition system that can be built for less than a third of the cost for a comparable commercial system. The materials and directions for the system are divided by subsystems, which allows the system to be easily built, customized and upgraded, depending upon the needs of the user. We include the details for the specific hardware that will be needed, instructions for completing the build, and the software needed to automate the system. With a chemical vapor deposition system built as described, a variety of 2D nanomaterials and their heterostructures can be grown. Specifically, the experimental results clearly demonstrate the capability of this open-source design in producing high quality, 2D nanomaterials such as graphene and tungsten disulfide, which are at the forefront of research in emerging semiconductor devices, sensors, and energy storage applications.


Assuntos
Nanoestruturas/química , Nanotecnologia/instrumentação , Desenho de Equipamento , Gases/química , Grafite/química , Nanotecnologia/estatística & dados numéricos , Pressão , Software , Compostos de Tungstênio/química , Volatilização
5.
Rev. Soc. Bras. Med. Trop ; 52: e20180246, 2019. tab, graf
Artigo em Português | LILACS | ID: biblio-1041535

RESUMO

Abstract INTRODUCTION: Leishmaniasis is a global public health concern. Currently available treatments are associated with considerable side effects. The use of nanotechnology has shown promise for improving efficacy and bioavailability and minimizing side effects. METHODS: This study investigated available literature, including patents and scientific articles, to identify advances in the use of nanotechnology for the treatment of leishmaniasis. RESULTS: Our findings revealed a stable number of patents and scientific articles published over the past five years. CONCLUSIONS: There is a need to intensify research on the use of nanotechnology for the treatment of leishmaniasis.


Assuntos
Humanos , Leishmaniose/tratamento farmacológico , Nanotecnologia/estatística & dados numéricos , Pesquisa Biomédica/estatística & dados numéricos , Antiprotozoários/administração & dosagem , Patentes como Assunto/estatística & dados numéricos , Bibliometria
6.
Nat Biotechnol ; 36(5): 460-468, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29658943

RESUMO

The speed of super-resolution microscopy methods based on single-molecule localization, for example, PALM and STORM, is limited by the need to record many thousands of frames with a small number of observed molecules in each. Here, we present ANNA-PALM, a computational strategy that uses artificial neural networks to reconstruct super-resolution views from sparse, rapidly acquired localization images and/or widefield images. Simulations and experimental imaging of microtubules, nuclear pores, and mitochondria show that high-quality, super-resolution images can be reconstructed from up to two orders of magnitude fewer frames than usually needed, without compromising spatial resolution. Super-resolution reconstructions are even possible from widefield images alone, though adding localization data improves image quality. We demonstrate super-resolution imaging of >1,000 fields of view containing >1,000 cells in ∼3 h, yielding an image spanning spatial scales from ∼20 nm to ∼2 mm. The drastic reduction in acquisition time and sample irradiation afforded by ANNA-PALM enables faster and gentler high-throughput and live-cell super-resolution imaging.


Assuntos
Aprendizado Profundo , Microscopia de Fluorescência/métodos , Microscopia/métodos , Nanotecnologia/métodos , Algoritmos , Microscopia/estatística & dados numéricos , Microscopia de Fluorescência/estatística & dados numéricos , Nanotecnologia/estatística & dados numéricos , Redes Neurais de Computação
7.
AAPS J ; 19(3): 642-651, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28281194

RESUMO

Nanocrystal technology has emerged as a valuable tool for facilitating the delivery of poorly water-soluble active pharmaceutical ingredients (APIs) and enhancing API bioavailability. To date, the US Food and Drug Administration (FDA) has received over 80 applications for drug products containing nanocrystals. These products can be delivered by different routes of administration and are used in a variety of therapeutic areas. To aid in identifying key developmental considerations for these products, a retrospective analysis was performed on the submissions received by the FDA to date. Over 60% of the submissions were for the oral route of administration. Based on the Biopharmaceutics Classification System (BCS), most nanocrystal drugs submitted to the FDA are class II compounds that possess low aqueous solubility and high intestinal permeability. Impact of food on drug bioavailability was reduced for most nanocrystal formulations as compared with their micronized counterparts. For all routes of administration, dose proportionality was observed for some, but not all, nanocrystal products. Particular emphasis in the development of nanocrystal products was placed on the in-process tests and controls at critical manufacturing steps (such as milling process), mitigation and control of process-related impurities, and the stability of APIs or polymorphic form (s) during manufacturing and upon storage. This emphasis resulted in identifying challenges to the development of these products including accurate determination of particle size (distribution) of drug substance and/or nanocrystal colloidal dispersion, identification of polymorphic form (s), and establishment of drug substance/product specifications.


Assuntos
Indústria Farmacêutica/estatística & dados numéricos , Nanopartículas , Nanotecnologia/estatística & dados numéricos , Preparações Farmacêuticas/química , Indústria Farmacêutica/métodos , Indústria Farmacêutica/normas , Preparações Farmacêuticas/normas
8.
Nanomedicine (Lond) ; 9(10): 1475-86, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25253496

RESUMO

We explore at a world level the awareness of nanotechnology expressed through the most popular online social media: Facebook. We aimed at identifying future trends, the most interested countries and the public perception of ethics, funding and economic issues. We found that graphene and carbon nanotubes are the most followed nanomaterials. Our poll showed that the continents with the most interest are Asia and Africa. A total of 43% would like to have a world commission regulating nanomedicine. In addition, 43% would give priority to theranostics. Over 90% believe that nanomedicine has an economic impact. Finally, we observed that the continents of living and origin of poll contributors correlated with ethic and funding opinions. This study highlights the potential of online social media to influence scientific communities, grant committees and nanotechnology companies, spreading nanotechnology awareness in emerging countries and among new generations.


Assuntos
Atitude Frente a Saúde , Mineração de Dados/estatística & dados numéricos , Nanomedicina/estatística & dados numéricos , Nanotecnologia/estatística & dados numéricos , Opinião Pública , Mídias Sociais/estatística & dados numéricos , Internacionalidade
9.
Int J Nanomedicine ; 9: 2627-34, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24920900

RESUMO

This research maps the knowledge translation process for two different types of nanotechnologies applied to cancer: liposomes and metallic nanostructures (MNs). We performed a structural analysis of citation networks and text mining supported in controlled vocabularies. In the case of liposomes, our results identify subnetworks (invisible colleges) associated with different therapeutic strategies: nanopharmacology, hyperthermia, and gene therapy. Only in the pharmacological strategy was an organized knowledge translation process identified, which, however, is monopolized by the liposomal doxorubicins. In the case of MNs, subnetworks are not differentiated by the type of therapeutic strategy, and the content of the documents is still basic research. Research on MNs is highly focused on developing a combination of molecular imaging and photothermal therapy.


Assuntos
Lipossomos/uso terapêutico , Nanopartículas Metálicas/uso terapêutico , Nanotecnologia/estatística & dados numéricos , Publicações Periódicas como Assunto/estatística & dados numéricos , Pesquisa Translacional Biomédica/estatística & dados numéricos , Internacionalidade
10.
J Nanosci Nanotechnol ; 14(6): 4700-5, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24738449

RESUMO

China has become a key player in the global nanotechnology field, however, no surveys have specifically examined safety practices in the Chinese nano-laboratories in depth. This study reports results of a survey of 300 professionals who work in research laboratories that handle nanomaterials in China. We recruited participants at three major nano-research laboratories (which carry out research in diverse fields such as chemistry, material science, and biology) and the nano-chemistry session of the national meeting of the Chinese Chemical Society. Results show that almost all nano-research laboratories surveyed had general safety regulations, whereas less than one third of respondents reported having nanospecific safety rules. General safety measures were in place in most surveyed nano-research laboratories, while nanospecific protective measures existed or were implemented less frequently. Several factors reported from the scientific literature including nanotoxicology knowledge gaps, technical limitations on estimating nano-exposure, and the lack of nano-occupational safety legislation may contribute to the current state of affairs. With these factors in mind and embracing the precautionary principle, we suggest strengthening or providing nanosafety training (including raising risk awareness) and establishing nanosafety guidelines in China, to better protect personnel in the nano-workplace.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Laboratórios/estatística & dados numéricos , Nanopartículas/intoxicação , Nanotecnologia/estatística & dados numéricos , Gestão da Segurança/estatística & dados numéricos , Coleta de Dados , Humanos , Nanotecnologia/métodos , Gestão da Segurança/métodos
12.
Nat Commun ; 2: 570, 2011 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-22146389

RESUMO

The decoherence of quantum objects is a critical issue in quantum science and technology. It is generally believed that stronger noise causes faster decoherence. Strikingly, recent theoretical work suggests that under certain conditions, the opposite is true for spins in quantum baths. Here we report an experimental observation of an anomalous decoherence effect for the electron spin-1 of a nitrogen-vacancy centre in high-purity diamond at room temperature. We demonstrate that, under dynamical decoupling, the double-transition can have longer coherence time than the single-transition even though the former couples to the nuclear spin bath as twice strongly as the latter does. The excellent agreement between the experimental and theoretical results confirms the controllability of the weakly coupled nuclear spins in the bath, which is useful in quantum information processing and quantum metrology.


Assuntos
Diamante/análise , Teoria da Informação , Modelos Teóricos , Nanotecnologia/métodos , Teoria Quântica , Isótopos de Carbono/química , Cristalização , Espectroscopia de Ressonância de Spin Eletrônica , Elétrons , Lasers , Micro-Ondas , Nanotecnologia/estatística & dados numéricos , Nitrogênio/química , Detecção de Spin , Temperatura
13.
Biochem Biophys Res Commun ; 414(2): 419-24, 2011 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-21971551

RESUMO

This study demonstrates the feasibility of creating a self-powered (galvanic) electroporation device using the singularity-induced nano-electroporation configuration. Using this configuration, the electric field in a galvanic electrochemical cell can be amplified and used for electroporation. A secondary current distribution model of a self-powered electroporation device shows that the device can create both reversible and irreversible electroporation-inducing electric field magnitudes, and generate a small amount of power.


Assuntos
Eletroporação/instrumentação , Nanotecnologia/instrumentação , Condutividade Elétrica , Eletroporação/estatística & dados numéricos , Modelos Estatísticos , Nanotecnologia/estatística & dados numéricos
14.
J Occup Environ Med ; 53(6 Suppl): S62-7, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21654420

RESUMO

OBJECTIVE: Toxicology studies suggest that carbon nanotube (CNT) exposures may cause adverse pulmonary effects. This study identified all US engineered carbonaceous nanomaterial (ECN) manufacturers, determined workforce size and growth, and characterized the materials produced to determine the feasibility of occupational ECN exposure studies. METHODS: Eligible companies were identified; information was assembled on the companies and nanomaterials they produced; and the workforce size, location, and growth were estimated. RESULTS: Sixty-one companies manufacturing ECN in the United States were identified. These companies employed at least 620 workers; workforce growth was projected at 15% to 17% annually. Most companies produced or used CNT. Half the eligible companies provided information about material dimensions, quantities, synthesis methods, and worker exposure reduction strategies. CONCLUSIONS: Industrywide exposure assessment studies appear feasible; however, cohort studies are likely infeasible because of the small, scattered workforce.


Assuntos
Nanotecnologia/estatística & dados numéricos , Projetos de Pesquisa Epidemiológica , Fulerenos/provisão & distribuição , Grafite/provisão & distribuição , Humanos , Nanofibras/provisão & distribuição , Nanotubos de Carbono/provisão & distribuição , Inquéritos e Questionários , Estados Unidos , Recursos Humanos
15.
J Biomed Nanotechnol ; 7(1): 18, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21485780

RESUMO

Identifying new risks due to new technologies like nanotechnology is a process that involves many uncertainties in which a balance must be found between a dynamic and a careful approach. The challenge is to prevent any occupational damage to health without creating unnecessary concern.


Assuntos
Nanotecnologia/estatística & dados numéricos , Doenças Profissionais/epidemiologia , Exposição Ocupacional/análise , Exposição Ocupacional/estatística & dados numéricos , Vigilância da População/métodos , Medição de Risco/métodos , Humanos , Prevalência , Gestão de Riscos
16.
Ind Health ; 49(3): 280-96, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21372443

RESUMO

A number of reports have been published regarding the applicability of existing regulatory frameworks to protect consumers and the environment from potentially adverse effects related to introduction of nanomaterials into commerce in the United States and the European Union. However, a detailed comparison of the regulatory approaches to worker safety and health in the USA and in the EU is lacking. This report aims to fill this gap by reviewing regulatory frameworks designed to protect workers and their possible application to nanotechnology.


Assuntos
Nanotecnologia/legislação & jurisprudência , Saúde Ocupacional/legislação & jurisprudência , União Europeia , Regulamentação Governamental , Humanos , Nanotecnologia/normas , Nanotecnologia/estatística & dados numéricos , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/legislação & jurisprudência , Exposição Ocupacional/estatística & dados numéricos , Saúde Ocupacional/estatística & dados numéricos , Medição de Risco , Estados Unidos , United States Occupational Safety and Health Administration
17.
Rev Environ Health ; 26(4): 251-68, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22435324

RESUMO

Nanotechnology is currently used in industry, medicine, and military applications, as well as in more than 300 commercial products. Yet, the same properties that make these particles exciting for technology also make them daunting public health concerns because their toxicity is unknown and relatively unexplored. Increased attention is being placed on the study of metal particle genotoxicity; however, a lot of unknowns remain about their effects and the mechanisms. In this article, we highlight some metal and metal oxide nanoparticles of interest and discuss the current in vivo and in vitro studies of genotoxic effects. Many metal nanoparticles were found to cause chromosomal aberrations, DNA strand breaks, oxidative DNA damage, and mutations. Inconsistencies are found in the literature, however, thus drawing conclusions is difficult due to a variety of factors. Therefore, the areas requiring further attention are highlighted and recommendations to improve our understanding of the genotoxic potential are addressed.


Assuntos
Poluentes Ambientais/toxicidade , Nanopartículas Metálicas/toxicidade , Mutagênese/efeitos dos fármacos , Mutagênicos/toxicidade , Aberrações Cromossômicas/induzido quimicamente , Dano ao DNA/efeitos dos fármacos , Exposição Ambiental/efeitos adversos , Exposição Ambiental/estatística & dados numéricos , Humanos , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Nanotecnologia/estatística & dados numéricos , Estresse Oxidativo/efeitos dos fármacos
18.
Analyst ; 136(3): 570-6, 2011 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-21072333

RESUMO

The functional properties of many technological surfaces in biotechnology, electronics, and mechanical engineering depend to a large degree on the individual features of their nanoscale surface texture, which in turn is a function of the surface manufacturing process. Among these features, the surface irregularities and self-similarity structures at different spatial scales, especially in the range of 1 to 100 nm, are of high importance because they greatly affect the surface interaction forces acting at a nanoscale distance. An analytical method for parameterizing the surface irregularities and their correlations in nanosurfaces imaged by atomic force microscopy (AFM) is proposed. In this method, flicker noise spectroscopy--a statistical physics approach--is used to develop six nanometrological parameters characterizing the high-frequency contributions of jump- and spike-like irregularities into the surface texture. These contributions reflect the stochastic processes of anomalous diffusion and inertial effects, respectively, in the process of surface manufacturing. The AFM images of the texture of corrosion-resistant magnetite coatings formed on low-carbon steel in hot nitrate solutions with coating growth promoters at different temperatures are analyzed. It is shown that the parameters characterizing surface spikiness are able to quantify the effect of process temperature on the corrosion resistance of the coatings. It is suggested that these parameters can be used for predicting and characterizing the corrosion-resistant properties of magnetite coatings.


Assuntos
Microscopia de Força Atômica/métodos , Nanoestruturas/análise , Nanotecnologia/métodos , Óxido Ferroso-Férrico/química , Modelos Teóricos , Nanoestruturas/química , Nanotecnologia/estatística & dados numéricos , Aço/química , Propriedades de Superfície
20.
Adv Exp Med Biol ; 680: 99-108, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20865491

RESUMO

Pattern recognition-informed (PRI) feedback using channel current cheminformatics (CCC) software is shown to be possible in "real-time" experimental efforts. The accuracy of the PRI classification is shown to inherit the high accuracy of our offline classifier: 99.9% accuracy in distinguishing between terminal base pairs of two DNA hairpins. The pattern recognition software consists of hidden Markov model (HMM) feature extraction software, and support vector machine (SVM) classification/ clustering software that is optimized for data acquired on a nanopore channel detection system. For general nanopore detection, the distributed HMM and SVM processing used here provides a processing speedup that allows pattern recognition to complete within the time frame of the signal acquisition - where the sampling is halted if the blockade signal is identified as not in the desired subset of events (or once recognized as nondiagnostic in general). We demonstrate that Nanopore Detection with PRI offers significant advantage when applied to data acquisition on antibody-antigen system, or other complex biomolecular mixtures, due to the reduction in wasted observation time on eventually rejected "junk" (nondiagnostic) signals.


Assuntos
Técnicas Biossensoriais/estatística & dados numéricos , Reconhecimento Automatizado de Padrão/estatística & dados numéricos , Inteligência Artificial , Biologia Computacional , DNA/química , DNA/genética , Retroalimentação , Cadeias de Markov , Nanoporos , Nanotecnologia/estatística & dados numéricos
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