Hot electron driven enhancement of spin-lattice coupling in 4f ferromagnets observed by femtosecond x-ray magnetic circular dichroism

Femtosecond x-ray magnetic circular dichroism was used to study the time-dependent magnetic moment of 4 fs electrons in the ferromagnets Gd and Tb, which are known for their different spin-lattice coupling. We observe a two-step demagnetization with an ultrafast demagnetization time of 750 fs identical for both systems and slower times which differ sizeably with 40 ps for Gd and 8 ps for Tb. We conclude that spin-lattice coupling in the electronically excited state is enhanced up to orders of magnitude compared to equilibrium.Comment: added reference 24, clarified the meaning of photo-induced, emphasized that XMCD probes the magnetic moment localized at 4f electron

Considerations on a Definition of Nanomaterial for Regulatory Purposes

The recent EU Cosmetic Products Regulation includes a labelling obligation for nanomaterials in the list of ingredients, in order to allow consumers to make a choice. Similar provisions are now being considered for other regulations/directives, e.g. the Novel Foods Regulation. Also the European chemicals legislation REACH may need adjustments to address and control the potential risk of nanomaterials. The introduction of these provisions specific to nanomaterials requires the adoption of a definition of the term "nanomaterial". This need is also acknowledged by the European Parliament which has called for a comprehensive science-based definition in Community legislation. This report reviews and discusses issues and challenges related to a definition of "nanomaterial". It gives a short overview about what may be considered as nanomaterials, their novel properties and applications. The need for a definition of nanomaterial is discussed, and the question of what should be achieved by a definition is addressed. The report gives an overview of definitions by international, national and European institutions, and lists approaches used in European legislation. It summarises the advantages and shortcomings of different elements typically used in available definitions, regarding their applicability in a regulatory context. The following three key elements are identified as being crucial in achieving a single, enforceable definition of nanomaterial: (i) the term "material", (ii) the nanoscale, and (iii) specific nanoscale properties. Material and nanoscale should both preferably be defined precisely in order to ease enforceability. This implies the introduction of precise nanoscale limits and instructions on how such limits can be applied to nanoscale materials with size distributions. Size-derived properties, nanostructured features, nanoscale materials incorporated in a matrix and the origin of the material are also issues to be considered. Key words: nanomaterial, definition, nanoscale, physico-chemical properties, Cosmetic Products Regulation, REACH.JRC.DG.I.5-Nanobioscience

A brief history of otorhinolaryngolgy: otology, laryngology and rhinology

Ears, nose and throat have intrigued humanity since immemorial times. Treatments for the larynx, the nose and the ear and also surgeries were practiced by Greek, Hindu and Byzantine doctors. In the 20th century clinical and surgical innovations were incorporated, thanks to new anesthesia techniques, antibiotics, radiology and new technologies. AIM AND METHOD: show the evolution of this science throughout the times, recognizing important persons in otology, rhinology and laryngology. RESULTS AND CONCLUSION: Understanding the evolutions in clinical and surgical anatomy, physiology, treatment modalities, and the personalities that lead to these advances is of great importance for the evolution of medical science. Otorhinolaryngology has a very rich history, with important collaborators and personalities in the history of medicine. The specialty was one of the first to use local anesthesia for procedures, pioneer in treatments with devices that recouped hearing and the use of microscopes in surgeries. Few medical specialties had suffered as many changes and scientific developments in these last decades as Otorhinolaryngology had, with the advantage of incorporating technologies such as endoscopy, radiology, microsurgery and information technology.O nariz, a garganta e o ouvido intrigam a humanidade desde os períodos mais remotos. Tratamentos laringológicos, rinológicos e otológicos, além de cirurgias, já eram praticados por médicos gregos, hindus e bizantinos. No século XX inovações clínicas e cirúrgicas foram incorporadas graças às novas técnicas anestésicas, aos antibióticos, à radiologia e às novas tecnologias. OBJETIVO E MÉTODO: Mostrar a evolução desta ciência ao longo dos tempos, reconhecendo figuras importantes da otologia, rinologia e laringologia por revisão em literatura. RESULTADO E CONCLUSÃO: O conhecimento das evoluções em anatomia, fisiologia, tratamentos clínicos e cirúrgicos, além das personalidades que conduziram a estes avanços é de grande importância para que a ciência médica evolua cada vez mais. A Otorrinolaringologia tem história muito rica, com importantes colaboradores e figuras de renome para a história da medicina. A especialidade foi uma das primeiras a utilizar anestesia local para realização de procedimentos, pioneira em tratamentos com próteses que recuperavam a audição e teve a primazia na utilização de microscópios em cirurgias. Poucas especialidades médicas sofreram tantas mudanças e desenvolvimentos científicos nestas últimas décadas quanto a Otorrinolaringologia que teve a vantagem de incorporar tecnologias na endoscopia, radiologia, microcirurgia e uso da informática.Hospital Prof. Edmundo VasconcelosHCFMUSPUNIFESPHospital Prof. Edmundo Vasconcelos Centro de Otorrinolaringologia de São PauloUniversidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina (EPM)Hospital Professor Edmundo Vasconcelos Centro de Otorrinolaringologia de São Paulo Setor de Otorrinolaringologia PediátricaUNIFESP, EPMSciEL

Characteristics of the Multi-Telescope Coincidence Trigger of the HEGRA IACT System

The HEGRA--collaboration is operating a system of imaging atmospheric Cherenkov telescopes to search for sources of TeV-gamma-rays. Air showers are observed in stereoscopic mode with several telescopes simultaneously. To trigger the telescope system a versatile two-level trigger scheme has been implemented, which allows a significant reduction of the energy threshold with respect to single telescopes. The technical implementation of this trigger scheme and the performance of the trigger system are described. Results include the dependence of single- and multi-telescope trigger rates on the trigger thresholds, on the orientation of the telescopes, and on the type of the primary particle.Comment: 17 Pages, 10 figures, Late

Towards a review of the EC Recommendation for a definition of the term "nanomaterial": Part 3: Scientific-technical evaluation of options to clarify the definition and to facilitate its implementation

This report provides the JRC's scientific-technical evaluation of options to clarify the EC Recommendation on a definition of nanomaterial, published in 2011 (EC Recommendation 2011/696/EU). It is a follow-up report of two previous JRC publications, which compiled feedback on the experiences of stakeholders with the EC nanomaterial definition collected by JRC in 2013 and early 2014 (EUR 26567 EN, 2014), and provided an assessment of the collected information (EUR 26744 EN, 2014). The three JRC reports are part of the review process foreseen in the 2011 EC Recommendation. The evaluation shows that the scope of the definition regarding the origin of nanomaterials should remain unchanged, addressing natural, incidental as well as manufactured nanomaterials. Moreover, because of the regulatory purpose of the definition, there is little evidence to support deviating from size as the sole defining property of a nanoparticle or from the range of 1 nm to 100 nm as definition of the nanoscale. Besides the need for clarification of some terms used in the definition additional implementation guidance would be useful. The role of the volume specific surface area deserves clarification and a method to prove that a material is not a nanomaterial would be helpful. A strategy how to avoid unintended inclusion of materials and the list of explicitly included materials deserve also attention.JRC.I.4-Nanobioscience

Impact of Engineered Nanomaterials on Health: Considerations for Benefit-Risk Assessment

Nanotechnology encompasses the design, characterisation, production and application of materials and systems by controlling shape and size at the nanoscale (nanometres). Nanomaterials may differ from other materials because of their relatively large specific surface area, such that surface properties become particularly important. There has been rapid growth in investment in nanotechnology by both the public and private sectors worldwide. In the EU, nanotechnology is expected to become an important strategic contributor to achieving economic gain and societal and individual benefits. At the same time there is continuing scientific uncertainty and controversy about the safety of nanomaterials. It is important to ensure that timely policy development takes this into consideration. Uncertainty about safety may lead to polarised public debate and to business unwillingness to invest further. A clear regulatory framework to address potential health and environmental impacts, within the wider context of evaluating and communicating the benefit-risk balance, must be a core part of Europe's integrated efforts for nanotechnology innovation. While a number of studies have been carried out on the effect of environmental nanoparticles, e.g. from combustion processes, on human health, there is yet no generally acceptable paradigm for safety assessment of nanomaterials in consumer and other products. Therefore, a working group was established to consider issues for the possible impact of nanomaterials on human health focussing specifically on engineered nanomaterials. This represents the first joint initiative between EASAC and the Joint Research Centre of the European Commission. The working group was given the remit to describe the state of the art of benefits and potential risks, current methods for safety assessment, and to evaluate their relevance, identify knowledge gaps in studying the safety of current nanomaterials, and recommend on priorities for nanomaterial research and the regulatory framework. This report focuses on key principles and issues, cross-referencing other sources for detailed information, rather than attempting a comprehensive account of the science. The focus is on human health although environmental effects are also discussed when directly relevant to healt

Towards a review of the EC Recommendation for a definition of the term "nanomaterial" Part 2: Assessment of collected information concerning the experience with the defintion

This report provides the JRC assessment of feedback on the experiences of stakeholders with the EC nanomaterial definition, published in 2011 (EC Recommendation 2011/696/EU). The report is a follow-up report of the previous JRC report (EUR 26567 EN, 2014), which compiled feedback collected by JRC in 2013 and early 2014, partly through a dedicated survey. Based on the current report, JRC will prepare a set of recommendations for the revision of the EC nanomaterial definition, as part of the review process foreseen in the 2011 EC Recommendation.JRC.D.2-Standards for Innovation and sustainable Developmen

Breaking paradigms in severe epistaxis: the importance of looking for the S-point

Introduction: Since the introduction of nasal endoscopy into the field of Otorhinolaryngology, the treatment paradigm for cases of severe epistaxis has shifted toward early and precise identification of the bleeding site. Although severe epistaxis is usually considered to arise from posterior bleeding, an arterial vascular pedicle in the superior portion of the nasal septum, around the axilla projection of the middle turbinate, posterior to the septal body, frequently has been observed. That vascular pedicle was named the Stamm's S-point. Objective: The aim of this study was to describe the S-point and report cases of severe epistaxis originating from it. Methods: A retrospective case series study was conducted. Nine patients with spontaneous severe epistaxis, where the S-point was identified as the source of bleeding, were treated between March 2016 and March 2017. Results: Male predominance (77.8%) with age average of 59.3 years old were reported. Most cases presented comorbidities (88.9%) and were not taking acetylsalicylic acid (66.7%). A predominance of left sided involvement (55.6%) and anteroposterior bleeding being the principal initial presentation (77.8%) was seen. Six patients (66.7%) presented with hemoglobin levels below 10g/dL, and four (44.4%) required blood transfusion. Cauterization of S-point was performed in all patients, with complete resolution of bleeding. No patient experienced recurrence of severe epistaxis. Conclusion: The Stamm's S-point, a novel source of spontaneous severe epistaxis, is reported, and its cauterization was effective and safe. Otolaryngologists must actively seek this site of bleeding in cases of severe epistaxis. (C) 2018 Associacao Brasileira de Otorrinolaringologia e Cirurgia Cervico-Facial. Published by Elsevier Editora Ltda. This is an open access article under the CC BY license.Introdução: Desde a introdução da endoscopia nasal no campo de otorrinolaringologia, o paradigma de tratamento para casos graves de epistaxe voltou-se para a identificação precoce e correta do local de sangramento. Embora a epistaxe grave seja geralmente considerada uma hemorragia posterior, um pedículo vascular arterial tem sido frequentemente observado na porção superior do septo nasal, ao redor da projeção da axila da concha média, posterior ao tubérculo septal. Esse pedículo vascular foi chamado de Stamm's S-point. Objetivo: Descrever o S-point e relatar casos graves de epistaxe que se originam nesse local. Método: Um estudo retrospectivo de série de casos foi conduzido. Nove pacientes com epistaxe grave espontânea, na qual o S-point foi identificado como a fonte do sangramento, foram tratados de março de 2016 a março de 2017. Resultados: Houve predominância do sexo masculino (77,8%) com média de 59,3 anos. A maioria dos casos apresentava comorbidades (88,9%), mas sem uso de ácido acetilsalicílico (66,7%). Observou-se predominância do lado esquerdo (55,6%) com sangramento anteroposterior como a principal apresentação inicial (77,8%). Seis pacientes (66,7%) apresentaram níveis de hemoglobina inferiores a 10 g/dL e quatro (44,4%) necessitaram de transfusão sanguínea. Cauterização do S-point foi feita em todos os pacientes, com resolução completa do sangramento. Nenhum paciente apresentou recorrência de epistaxe grave. Conclusão: O Stamm's S-point é relatado como uma nova região de origem de epistaxe grave espontânea e o tratamento feito com cauterização foi eficaz e seguro. Os otorrinolaringologistas devem buscar ativamente esse local de sangramento em casos de epistaxe grave.Univ Fed Sao Paulo, UNIFESP, Setor Rinol,Escola Paulista Med, Dept Otorrinolaringol & Cirurgia Cabeca & Pescoco, Sao Paulo, SP, BrazilComplexo Hosp Edmundo Vasconcelos, Ctr Otorrinolaringol & Fonoaudiol, Sao Paulo, SP, BrazilPoliclin Botafogo, Dept Otorrinolaringol, Rio De Janeiro, RJ, BrazilUniv Fed Sao Paulo, UNIFESP, Setor Rinol,Escola Paulista Med, Dept Otorrinolaringol & Cirurgia Cabeca & Pescoco, Sao Paulo, SP, BrazilSciEL

Basic comparison of particle size distribution measurements of pigments and fillers using commonly available industrial methods

The Nanobiosciences Unit of the Joint Research Centre’s Institute for Health and Consumer Protection and Eurocolour, the association of European pigments, dyes and fillers industry, have carried out a program of work to evaluate a number of instrumental methods of measuring particle size distributions as required for assessing compliance versus the EU Recommendation for the definition on nanomaterials. The study has examined the use of five instrumental methods applied to a range of eight widely different but industrially relevant powder pigments. The techniques examined were Laser Diffraction (LD), Dynamic Light Scattering (DLS), Centrifugal Liquid Sedimentation (CLS), Volume Specific Surface Area (VSSA) and Electron Microscopy (EM). This report describes the materials studied and the preparative and analytical methods used. Individual chapters provide an overview of the single analytical methods used together with a summary of the results obtained using each particular method. In considering the results of this study it is important to note that the aim was not to determine the optimum conditions for every individual sample but rather to produce and evaluate data which could be considered representative of that obtainable in industrial laboratories using existing instrumental facilities operated by experienced but not specialised operators. The report discusses the challenges of using these instrumental methods to obtain a simple unambiguous classification of the test materials according to the EC definition.JRC.I.4-Nanobioscience

Towards a review of the EC Recommendation for a definition of the term "nanomaterial"; Part 1: Compilation of information concerning the experience with the definition

In October 2011 the European Commission (EC) published a Recommendation on the definition of nanomaterial (2011/696/EU). The purpose of this definition is to enable determination when a material should be considered a nanomaterial for regulatory purposes in the European Union. In view of the upcoming review of the current EC Definition of the term 'nanomaterial' and noting the need expressed by the EC Environment Directorate General and other Commission services for a set of scientifically sound reports as the basis for this review, the EC Joint Research Centre (JRC) prepares three consecutive reports, of which this is the first. This Report 1 compiles information concerning the experience with the definition regarding scientific-technical issues that should be considered when reviewing the current EC definition of nanomaterial. Based on this report and the feedback received, JRC will write a second, follow-up report. In this Report 2 the JRC will provide a detailed assessment of the scientific-technical issues compiled in Report 1, in relation to the objective of reviewing the current EC nanomaterial definition.JRC.I.4-Nanobioscience