Scanning nano-spin ensemble microscope for nanoscale magnetic and thermal imaging

Quantum sensors based on solid-state spins provide tremendous opportunities in a wide range of fields from basic physics and chemistry to biomedical imaging. However, integrating them into a scanning probe microscope to enable practical, nanoscale quantum imaging is a highly challenging task. Recently, the use of single spins in diamond in conjunction with atomic force microscopy techniques has allowed significant progress towards this goal, but generalisation of this approach has so far been impeded by long acquisition times or by the absence of simultaneous topographic information. Here we report on a scanning quantum probe microscope which solves both issues, by employing a nano-spin ensemble hosted in a nanodiamond. This approach provides up to an order of magnitude gain in acquisition time, whilst preserving sub-100 nm spatial resolution both for the quantum sensor and topographic images. We demonstrate two applications of this microscope. We first image nanoscale clusters of maghemite particles through both spin resonance spectroscopy and spin relaxometry, under ambient conditions. Our images reveal fast magnetic field fluctuations in addition to a static component, indicating the presence of both superparamagnetic and ferromagnetic particles. We next demonstrate a new imaging modality where the nano-spin ensemble is used as a thermometer. We use this technique to map the photo-induced heating generated by laser irradiation of a single gold nanoparticle in a fluid environment. This work paves the way towards new applications of quantum probe microscopy such as thermal/magnetic imaging of operating microelectronic devices and magnetic detection of ion channels in cell membranes.Comment: 22 pages including Supporting Information. Changes to v1: affiliations and funding information updated, plus minor revisions to the main tex

Préface

Ce volume fait suite à un colloque qui s’est tenu les 25 et 26 mars 2010 à la faculté des Sciences et Techniques de l’université Henri Poincaré de Nancy. L’objectif était de faire se rencontrer philosophes, historiens des sciences, physiciens et mathématiciens autour de la question de la nature de l’espace et du temps. Cette question connaît indéniablement un important regain d’intérêt dans la communauté scientifique. Y répondre est devenu, pour de nombreux physiciens, primordial dans la cons..

Maturity matrix assessment : evaluation of energy efficiency strategies in Brussels historic residential stock

Energy retrofitting of historic or existing buildings is a challenge that it has not yet been properly solved. Multiple projects and methodologies are published every day but neither of them with the holistic approach that will assure success since the design phase. Nevertheless, these buildings play a key role in the achievement of the ambitious energy saving and greenhouse gas reduction targets that Europe has fixed for 2020 and 2050. Research has demonstrated that the impact in terms of decrease of energy use and CO2 will be strong, considering that, in Europe, 80% of the 2030 building stock already exists and 30% are historical buildings. To achieve these goals, reliable data about energy consumption, building components and systems performance of the existing building stock is needed. With the residential stock occupying a 75% of Europe’s floor space, this becomes a difficult task as this stock is never considered as a whole. Its components are installed, serviced and maintained by different companies and in different stages without a holistic approach to the overall building operation. The result is a lack of energy efficiency and feedback of the solutions implemented once the buildings are refurbished. This paper presents a pre-assessment methodology to tackle the energy retrofitting of historic and existing residential buildings based in the Maturity Matrix Assessment. The maturity of the implementation of energy efficiency measures in Brussels historic residential stock is evaluated to measure the gap between the “as is” and “to be” and define future appropriate strategies. The matrix synthetizes appropriate strategies for this specific stock that provides a global map of the problematic, requirements and solutions

Coherent beam combining with an ultrafast multicore Yb-doped fiber amplifier

International audienceActive coherent beam combination using a 7-non-coupled core,polarization maintaining, air-clad, Yb-doped fiber is demonstrated as amonolithic and compact power-scaling concept for ultrafast fiber lasers. Amicrolens array matched to the multicore fiber and an active phasecontroller composed of a spatial light modulator applying a stochasticparallel gradient descent algorithm are utilized to perform coherentcombining in the tiled aperture geometry. The mitigation of nonlineareffects at a pulse energy of 8.9 μJ and duration of 860 fs is experimentallyverified at a repetition rate of 100 kHz. The experimental combiningefficiency results in a far field central lobe carrying 49% of the total power,compared to an ideal value of 76%. This efficiency is primarily limited bygroup delay differences between cores which is identified as the maindrawback of the system. Minimizing these group delay issues, e.g. by usingshort and straight rod-type multicore fibers, should allow a practical powerscaling solution for femtosecond fiber systems

Patient-reported outcomes with lanreotide Autogel/Depot for carcinoid syndrome: An international observational study

Abstract BACKGROUND: Lanreotide Autogel/Depot effectively controls symptoms in patients with carcinoid syndrome associated with neuroendocrine tumours. Data on patient-reported outcomes are sparse. AIM: To evaluate the effect of lanreotide on patient-reported outcomes (PROs) with carcinoid syndrome. METHODS: This was an international, open-label, observational study of adults with neuroendocrine tumours and history of diarrhoea, receiving lanreotide for >3 months for relief of carcinoid syndrome symptoms. The primary PRO measure was satisfaction with diarrhoea control. Secondary PRO measures included severity, change in symptoms and impact on daily life of diarrhoea; and patient satisfaction with flushing control. RESULTS: Of 273 patients enrolled, 76% were 'completely' or 'rather' satisfied with diarrhoea control; 79% reported improvement in diarrhoea with lanreotide. The proportion of patients with 'mild', 'minimal', or 'no diarrhoea' increased from 33% before treatment to 75% during treatment; 75% were unconcerned about the impact of diarrhoea on daily life. Satisfaction with flushing control amongst patients with significant flushing at treatment initiation was 73%. CONCLUSIONS: Lanreotide treatment was associated with improvements in symptoms as well as a range of PROs in patients with neuroendocrine tumours and carcinoid syndrome (ClinicalTrials.gov: NCT01234168)

HIV viral load non-suppression and associated factors among pregnant and postpartum women in rural northeastern South Africa: a cross-sectional survey.

ObjectivesWe aimed to measure the prevalence of maternal HIV viral load (VL) non-suppression and assess associated factors, to evaluate progress towards United Nations-AIDS (UNAIDS) targets.DesignCross-sectional study.SettingThe eight largest community health centres of Ehlanzeni, a rural district in northeast South Africa.ParticipantsPregnant women living with HIV (WLHIV) in their third trimester and postpartum WLHIV and their biological infants, recruited equally across all stages of the first 24 months post partum, were included. A sample of 612 mothers participated from a target of 1000.Primary outcome measuresThe primary outcome was maternal VL (mVL) non-suppression (defined here as mVL >1000 copies/mL). We collected information on antiretroviral use, healthcare visits and sociodemographics through interviews and measured plasma mVL. Descriptive statistics, χ2 tests and multivariable logistic regression analysis were conducted.ResultsAll mothers (median age: 30 years) were on antiretroviral therapy (ART) and 24.9% were on ART ≤12 months. The prevalence of mVL non-suppression was 14.7% (95% CI: 11.3% to 19.0%), while 13.8% had low-level viraemia (50-1000 copies/mL). Most (68.9%) women had initiated breast feeding and 37.6% were currently breast feeding their infants. Being younger than 25 years (adjusted odds ratio (AOR): 2.6 (95% CI: 1.1 to 6.4)), on first-line ART (AOR: 2.3 (95% CI: 1.1 to 4.6)) and married/cohabiting (AOR: 1.9 (95% CI: 1.0 to 3.7)) were significantly associated with increased odds of mVL non-suppression.ConclusionsThe prevalence of mVL ≤1000 copies/mL of 85.3% among pregnant and postpartum WLHIV and attending public healthcare centres in this rural district is below the 2020 90-90-90 and 2030 95-95-95 UNAIDS targets. Given that low-level viraemia may also increase the risk of vertical HIV transmission, we recommend strengthened implementation of the new guidelines which include better ART options, improved ART regimen switching and mVL monitoring schedules, and intensified psychosocial support for younger women, while exploring district-level complementary interventions, to sustain VLs below 50 copies/mL among all women

Malaria and obesity: obese mice are resistant to cerebral malaria

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

The EMBL Nucleotide Sequence Database

The EMBL Nucleotide Sequence Database (http://www.ebi.ac.uk/embl), maintained at the European Bioinformatics Institute (EBI) near Cambridge, UK, is a comprehensive collection of nucleotide sequences and annotation from available public sources. The database is part of an international collaboration with DDBJ (Japan) and GenBank (USA). Data are exchanged daily between the collaborating institutes to achieve swift synchrony. Webin is the preferred tool for individual submissions of nucleotide sequences, including Third Party Annotation (TPA) and alignments. Automated procedures are provided for submissions from large-scale sequencing projects and data from the European Patent Office. New and updated data records are distributed daily and the whole EMBL Nucleotide Sequence Database is released four times a year. Access to the sequence data is provided via ftp and several WWW interfaces. With the web-based Sequence Retrieval System (SRS) it is also possible to link nucleotide data to other specialist molecular biology databases maintained at the EBI. Other tools are available for sequence similarity searching (e.g. FASTA and BLAST). Changes over the past year include the removal of the sequence length limit, the launch of the EMBLCDSs dataset, extension of the Sequence Version Archive functionality and the revision of quality rules for TPA data

EMBL Nucleotide Sequence Database: developments in 2005

The EMBL Nucleotide Sequence Database () at the EMBL European Bioinformatics Institute, UK, offers a comprehensive set of publicly available nucleotide sequence and annotation, freely accessible to all. Maintained in collaboration with partners DDBJ and GenBank, coverage includes whole genome sequencing project data, directly submitted sequence, sequence recorded in support of patent applications and much more. The database continues to offer submission tools, data retrieval facilities and user support. In 2005, the volume of data offered has continued to grow exponentially. In addition to the newly presented data, the database encompasses a range of new data types generated by novel technologies, offers enhanced presentation and searchability of the data and has greater integration with other data resources offered at the EBI and elsewhere. In stride with these developing data types, the database has continued to develop submission and retrieval tools to maximise the information content of submitted data and to offer the simplest possible submission routes for data producers. New developments, the submission process, data retrieval and access to support are presented in this paper, along with links to sources of further information