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1.
ChemSusChem ; 17(5): e202301746, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38214055

RESUMO

The "in situ electrolyte" displays a concept for electric double-layer- as well as metal-ion capacitors in which the by-products formed during carbon synthesis serve directly as electrolyte salt to minimize waste. In this work, the concept is applied for lithium- and sodium-based systems realizing EDLCs containing aqueous, "Water in Salt" (up to 1.8 V) as well as organic (2.4 V) electrolytes. Via the mechanochemical synthesis, carbon materials with surface areas up to 2000 m2 g-1 and an optimal amount of remaining by-product are designed from the renewable resource lignin. Different cation-anion combinations are enabled by further modification directly inside the pores creating imide-based salts which are tracked by synchrotron in situ XRD. By the addition of solvents, the EDLCs show good capacitances up to 21 F g-1 combined with excellent rate performances and stabilities. Moreover, the LiTFSI loaded carbon as positive electrode introduces a new tunable lithium alternative for the pre-lithiation of Li-ion capacitors displaying a good rate performance and cyclability.

2.
Chemistry ; 29(7): e202202860, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36314665

RESUMO

Mechanochemical reactions are solvent-free alternatives to solution-based syntheses enabling even conventionally impossible transformations. Their reaction pathways, however, usually remain unexplored within the heavily vibrating, dense milling vessels. Here, we showcase how the green organic solvent diethyl carbonate is synthesized mechanochemically from inorganic alkali carbonates and how the complementary combination of milling parameter studies, synchrotron X-ray diffraction real time monitoring, and quantum chemical calculations reveal the underlying reaction pathways. With this, reaction intermediates are identified, and chemical concepts of solution-chemistry are challenged or corroborated for mechanochemistry.

3.
ChemSusChem ; 15(16): e202200651, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35670243

RESUMO

The mechanochemical synthesis of nitrogen-rich nanoporous carbon materials has been scaled up using an extruder. Lignin, urea, and K2 CO3 were extruded under heat and pressure to yield nanoporous carbons with up to 3500 m2 g-1 specific surface area after pyrolysis. The route was further broadened by applying different nitrogen sources as well as sawdust as a low-cost renewable feedstock to receive carbons with a C/N ratio of up to 15 depending on nitrogen source and extrusion parameters. The texture of obtained carbons was investigated by scanning electron microscopy as well as argon and nitrogen physisorption, while the chemical structure was analyzed by X-ray photoelectron spectroscopy. The received carbon was tested as a supercapacitor electrode, showing comparable performance to similar ball-mill-synthesized materials. Lastly, the space-time yield was applied to justify the use of a continuous reactor versus the ball mill.


Assuntos
Carbono , Nanoporos , Carbono/química , Eletrodos , Nitrogênio/química , Solventes
4.
J Natl Cancer Inst ; 109(4)2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28376165

RESUMO

Clinical studies have shown plasma Epstein-Barr virus (EBV) DNA level to be an independent prognostic biomarker for nasopharyngeal carcinoma (NPC). However, the proportion of NPC patients whose tumors are associated with EBV vary with geographic location, and there are a variety of assays for plasma EBV. To develop the level of evidence needed to demonstrate the clinical utility of plasma EBV DNA detection for NPC patients and encourage widespread adoption of this biomarker test in clinical laboratories, validated harmonized assays are needed. In 2015, the National Cancer Institute (NCI) convened a Workshop on Harmonization of EBV Testing for Nasopharyngeal Cancer, where experts in head and neck oncology and laboratory medicine addressed the limitations of currently available polymerase chain reaction-based EBV DNA quantitation assays and discussed strategies for advancing the development of harmonized EBV DNA assays and their appropriate clinical use. This article presents the key recommendations to direct future efforts in assay harmonization and validation.


Assuntos
DNA Viral/sangue , Herpesvirus Humano 4/genética , Neoplasias Nasofaríngeas/sangue , Neoplasias Nasofaríngeas/virologia , Reação em Cadeia da Polimerase/normas , Biomarcadores Tumorais/sangue , Congressos como Assunto , Humanos , Neoplasias Nasofaríngeas/terapia , Reprodutibilidade dos Testes
5.
Toxicol Sci ; 155(1): 22-31, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27780885

RESUMO

Future Tox III, a Society of Toxicology Contemporary Concepts in Toxicology workshop, was held in November 2015. Building upon Future Tox I and II, Future Tox III was focused on developing the high throughput risk assessment paradigm and taking the science of in vitro data and in silico models forward to explore the question-what progress is being made to address challenges in implementing the emerging big-data toolbox for risk assessment and regulatory decision-making. This article reports on the outcome of the workshop including 2 examples of where advancements in predictive toxicology approaches are being applied within Federal agencies, where opportunities remain within the exposome and AOP domains, and how collectively the toxicology community across multiple sectors can continue to bridge the translation from historical approaches to Tox21 implementation relative to risk assessment and regulatory decision-making.


Assuntos
Toxicologia , Animais , Humanos , Técnicas In Vitro , Testes de Toxicidade
6.
Toxicol Sci ; 143(2): 256-67, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25628403

RESUMO

FutureTox II, a Society of Toxicology Contemporary Concepts in Toxicology workshop, was held in January, 2014. The meeting goals were to review and discuss the state of the science in toxicology in the context of implementing the NRC 21st century vision of predicting in vivo responses from in vitro and in silico data, and to define the goals for the future. Presentations and discussions were held on priority concerns such as predicting and modeling of metabolism, cell growth and differentiation, effects on sensitive subpopulations, and integrating data into risk assessment. Emerging trends in technologies such as stem cell-derived human cells, 3D organotypic culture models, mathematical modeling of cellular processes and morphogenesis, adverse outcome pathway development, and high-content imaging of in vivo systems were discussed. Although advances in moving towards an in vitro/in silico based risk assessment paradigm were apparent, knowledge gaps in these areas and limitations of technologies were identified. Specific recommendations were made for future directions and research needs in the areas of hepatotoxicity, cancer prediction, developmental toxicity, and regulatory toxicology.


Assuntos
Simulação por Computador , Técnicas In Vitro , Toxicologia/métodos , Toxicologia/tendências , Congressos como Assunto , Valor Preditivo dos Testes , Sociedades Científicas , Estados Unidos
7.
Age Ageing ; 44(2): 185-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25452294

RESUMO

The 20th century saw an unprecedented increase in average human lifespan as well as a rapid decline in human fertility in many countries of the world. The accompanying worldwide change in demographics of human populations is linked to unanticipated and unprecedented economic, cultural, medical, social, public health and public policy challenges, whose full implications on a societal level are only just beginning to be fully appreciated. Some of these implications are discussed in this commentary, an outcome of Cultures of Health and Ageing, a conference co-sponsored by the University of Copenhagen (UCPH) and the Center for Healthy Ageing at UCPH, which took place on 20-21 June 2014 in Copenhagen, Denmark. Questions discussed here include the following: what is driving age-structural change in human populations? how can we create 'age-friendly' societies and promote 'ageing-in-community'? what tools will effectively promote social engagement and prevent social detachment among older individuals? is there a risk that further extension of human lifespan would be a greater burden to the individual and to society than is warranted by the potential benefit of longer life?


Assuntos
Envelhecimento , Nível de Saúde , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/psicologia , Serviços de Saúde Comunitária , Características Culturais , Avaliação Geriátrica , Serviços de Saúde para Idosos , Humanos , Vida Independente , Pessoa de Meia-Idade , Pessoalidade , Dinâmica Populacional , Fatores Socioeconômicos
8.
Toxicol Sci ; 137(2): 269-77, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24204016

RESUMO

This article reports on the outcome of FutureTox, a Society of Toxicology (SOT) Contemporary Concepts in Toxicology (CCT) workshop, whose goal was to address the challenges and opportunities associated with implementing 21st century technologies for toxicity testing, hazard identification, and risk assessment. One goal of the workshop was to facilitate an interactive multisector and discipline dialog. To this end, workshop invitees and participants included stakeholders from governmental and regulatory agencies, research institutes, academia, and the chemical and pharmaceutical industry in Europe and the United States. The workshop agenda was constructed to collectively review and discuss the state-of-the-science in these fields, better define the problems and challenges, outline their collective goals for the future, and identify areas of common agreement key to advancing these technologies into practice.


Assuntos
Toxicologia/tendências , Congressos como Assunto , Europa (Continente) , Regulamentação Governamental , Medição de Risco , Toxicologia/legislação & jurisprudência , Toxicologia/métodos , Estados Unidos
10.
Mech Ageing Dev ; 132(10): 522-32, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21820462

RESUMO

The IARU Congress on Aging, Longevity and Health, held on 5-7 October 2010 in Copenhagen, Denmark, was hosted by Rector Ralf Hemmingsen, University of Copenhagen and Dean Ulla Wewer, Faculty of Health Sciences, University of Copenhagen and was organized by Center for Healthy Aging (CEHA) under the leadership of CEHA Managing Director Lene Juel Rasmussen and Prof. Vilhelm Bohr, National Institute on Aging, NIH, Baltimore, USA (associated to CEHA). The Congress was attended by approximately 125 researchers interested in and/or conducting research on aging and aging-related topics. The opening Congress Session included speeches by Ralf Hemmingsen, Ulla Wewer, and Lene Juel Rasmussen and Keynote Addresses by four world renowned aging researchers: Povl Riis (The Age Forum), Bernard Jeune (University of Southern Denmark), George Martin (University of Washington, USA) and Jan Vijg (Albert Einstein School of Medicine, USA) as well as a lecture discussing the art-science interface by Thomas Söderqvist (Director, Medical Museion, University of Copenhagen). The topics of the first six Sessions of the Congress were: Neuroscience and DNA damage, Aging and Stress, Life Course, Environmental Factors and Neuroscience, Muscle and Life Span and Life Span and Mechanisms. Two additional Sessions highlighted ongoing research in the recently established Center for Healthy Aging at the University of Copenhagen. This report highlights outcomes of recent research on aging-related topics, as described at the IARU Congress on Aging, Longevity and Health.


Assuntos
Envelhecimento , Saúde , Longevidade , Idoso , Animais , Dinamarca , Humanos , Pessoa de Meia-Idade
11.
Mech Ageing Dev ; 132(6-7): 340-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21708183

RESUMO

A workshop(1) to share, consider and discuss the latest developments in understanding xeroderma pigmentosum and other human diseases caused by defects in nucleotide excision repair (NER) of DNA damage was held on September 21-24, 2010 in Virginia. It was attended by approximately 100 researchers and clinicians, as well as several patients and representatives of patient support groups. This was the third in a series of workshops with similar design and goals: to emphasize discussion and interaction among participants as well as open exchange of information and ideas. The participation of patients, their parents and physicians was an important feature of this and the preceding two workshops. Topics discussed included the natural history and clinical features of the diseases, clinical and laboratory diagnosis of these rare diseases, therapeutic strategies, mouse models of neurodegeneration, molecular analysis of accelerated aging, impact of transcriptional defects and mitochondrial dysfunction on neurodegeneration, and biochemical insights into mechanisms of NER and base excision repair.


Assuntos
Senilidade Prematura , Reparo do DNA , Xeroderma Pigmentoso , Senilidade Prematura/diagnóstico , Senilidade Prematura/genética , Senilidade Prematura/metabolismo , Senilidade Prematura/terapia , Animais , Congressos como Assunto , Modelos Animais de Doenças , Humanos , Camundongos , Virginia , Xeroderma Pigmentoso/diagnóstico , Xeroderma Pigmentoso/genética , Xeroderma Pigmentoso/metabolismo , Xeroderma Pigmentoso/terapia
12.
Mutat Res ; 692(1-2): 53-60, 2010 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-20727903

RESUMO

The 3rd US-EU Workshop on systems level understanding of DNA damage responses was held from March 30 to April 1, 2009 in Egmond aan Zee, The Netherlands. Objectives of the workshop were (1) to assess the current science of the DDR, in particular network level responses to chemotherapeutic and environmentally induced DNA damage; and (2) to establish the basis for a reciprocal scientific exchange program between the EU and US in the relevant areas of DDR research. Here, we report the highlights of the meeting program and conclude that this third meeting in 2009 refined the role of DDR networks in human disease.


Assuntos
Dano ao DNA , Biologia de Sistemas , Biologia Computacional , Poluentes Ambientais/toxicidade , Humanos , Modelos Biológicos , Modelos Moleculares , Países Baixos , Medicina de Precisão
15.
Mech Ageing Dev ; 129(10): 614-23, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18789959

RESUMO

The mean age of the human population is steadily increasing in many areas around the globe, a phenomenon with large social, political, economic and biological/medical implications. Inevitably, this phenomenon is stimulating great interest in understanding and potentially modulating the process of human aging. To foster interactions and collaboration between diverse scientists interested in the biochemical, physiological, epidemiological and psychosocial aspects of aging, The University of Copenhagen Faculty of Health Sciences recently organized and co-sponsored a workshop entitled Aging-From Molecules to Populations. The following questions about human aging were discussed at the workshop: What is the limit of human life expectancy? What are the key indicators of human aging? What are the key drivers of human aging? Which genes have the greatest impact on human aging? How similar is aging-related cognitive decline to pathological cognitive decline associated with neurological disease? Are human progeriod diseases, characterized by premature aging, good models for "normal" human aging? Is delayed or "elite" aging informative about "normal" human aging? To what extent and by what mechanisms do early life environmental factors influence aging-associated physical and cognitive decline? To what extent and by what mechanism does the social environment influence life course outcomes? What physiological factors underlie the timing and extent of aging-associated physical and cognitive decline? How do cultural stereotypes and perceptions of aging influence the process and experience of aging? One of the primary outcomes of the workshop was a recognition that cross-disciplinary studies and "out-of-the-box" approaches, especially those that adopt an integrated life course perspective on human health status, are needed to expedite advances in aging research. This and other outcomes of the workshop are summarized and discussed in this report.


Assuntos
Envelhecimento , Animais , Doença Crônica/terapia , Citocinas/metabolismo , Dano ao DNA , Humanos , Inflamação , Expectativa de Vida , Modelos Biológicos , Modelos Genéticos , Mutagênese , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/terapia , Complexo de Endopeptidases do Proteassoma/metabolismo , Telômero/ultraestrutura
18.
Mech Ageing Dev ; 128(2): 229-35, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17361460

RESUMO

Researchers and clinicians interested in human diseases of DNA repair deficiency and premature aging gathered at the National Conference Center in Lansdowne, Virginia on 5-8 September 2006 to attend a workshop co-organized by Vilhelm Bohr (National Institute of Aging) and Kenneth Kraemer (National Cancer Institute). An important feature of this workshop was the participation of representatives from xeroderma pigmentosum (XP), Cockayne Syndrome (CS) and trichothiodystrophy (TTD) family support groups. Studies presented at the workshop described important new insights into the phenotypic complexity of XP, CS and TTD, renewed focus on the neurological manifestations of each of these diseases, as well as keen interest in the role of oxidative stress and mitochondrial dysfunction in neurodegenerative processes and normal and/or premature aging. This workshop report summarizes some of the presentations and outcomes of the workshop.


Assuntos
Senilidade Prematura/etiologia , Distúrbios no Reparo do DNA/etiologia , Envelhecimento , Síndrome de Cockayne/etiologia , Síndrome de Cockayne/genética , Distúrbios no Reparo do DNA/epidemiologia , Distúrbios no Reparo do DNA/genética , Doenças do Cabelo/etiologia , Doenças do Cabelo/genética , Humanos , Estresse Oxidativo , Prevalência , Xeroderma Pigmentoso/etiologia , Xeroderma Pigmentoso/genética
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