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Background The SCORE2 risk model has been recommended for cardiovascular risk assessment in individuals aged over 40 years without diabetes in 4 defined risk regions of Europe. We aimed to validate a novel SCORE2-DM model in Type 2 diabetes with additional risk factors mainly based on UK datasets, using federated databases from the EUBIROD network. Methods We defined a full operational protocol to implement a standard procedure for validation across contributing sources in Europe. The manual described inclusion/exclusion criteria (aged 40+, diagnosis of T2 diabetes at 30+, no prior CVD), risk factors measured over a baseline interval (1/2013-62015), target/competing events at follow-up (2015-2019). We specified a common data model with 9 steps required to process longitudinal records and deliver summary cohort data (one record per person). All rules were implemented in R and NeuBIRO, an original tool written in Java/Groovy and H2 SQL (https://github.com/eubirodnetwork/neubiro). Results Software was able to produce the following outputs at each source: distribution of risk factors by sex and 5-year age groups; Harrell's C-index and standard error of SCORE2 and SCORE2-DM by sex and 10-year age groups, C-index differences; average 5-year predictive vs observed risk by risk deciles; adjusted cumulative incidence of 5-year competing risk by sex and 5-year age groups. Code was packaged into a stand-alone bundle, with test data and coefficients ofthe SCORE2-DM model. The procedures allowed either creating cohort data autonomously to run the supplied R code, or let NeuBIRO complete all steps foreseen to deliver. Tests have been successfully completed in the derivation data, with results from federated databases expected to contribute to the final external validation of SCORE2-DM by midyear. Conclusions We defined a collaborative method to validate risk prediction models in high risk subgroups using international pooling of cohort data with privacy protection. Key messages • Collaborative methods to validate risk prediction models can enhance access to real world data for researchers across chronic diseases. • Implementation of flexible and reusable source code can increase opportunities to use prediction models for robust clinical decision making in multimorbidity.

In this paper, NICHE (Neutron Imaging for Cultural HEritage), the new neutron imaging facility of the Italian National Institute of Nuclear Physics (INFN) is shortly presented. We report on the main features of the beamline, the specifications of the detection set-up, and the performances of the imaging system. NICHE is installed at the TRIGA reactor of LENA (Laboratorio Energia Nucleare Applicata) Pavia University laboratory (Italy). The imaging facility was designed during 2020, installed in the spring 2021, and has been in operation since May 2021. NICHE is the first Italian neutron imaging station open to national external users through the INFN-CHNet network application system. NICHE allows users to obtain neutron radiographies and tomographies, thus allowing for morphological characterisation of samples. First results to highlight the potential of the facility are reported. In particular, we show the first results about spatial resolution measurement and 3D reconstruction to provide morphological analysis capabilities.

AIMS: To select a core list of standard outcomes for diabetes to be routinely applied internationally, including patient-reported outcomes.METHODS: We conducted a structured systematic review of outcome measures, focusing on adults with either type 1 or type 2 diabetes. This process was followed by a consensus-driven modified Delphi panel, including a multidisciplinary group of academics, health professionals and people with diabetes. External feedback to validate the set of outcome measures was sought from people with diabetes and health professionals.RESULTS: The panel identified an essential set of clinical outcomes related to diabetes control, acute events, chronic complications, health service utilisation, and survival that can be measured using routine administrative data and/or clinical records. Three instruments were recommended for annual measurement of patient-reported outcome measures: the WHO Well-Being Index for psychological well-being; the depression module of the Patient Health Questionnaire for depression; and the Problem Areas in Diabetes scale for diabetes distress. A range of factors related to demographic, diagnostic profile, lifestyle, social support and treatment of diabetes were also identified for case-mix adjustment.CONCLUSIONS: We recommend the standard set identified in this study for use in routine practice to monitor, benchmark and improve diabetes care. The inclusion of patient-reported outcomes enables people living with diabetes to report directly on their condition in a structured way.

Background: International comparisons of diabetes-related lower extremity amputation rates are still hampered by different criteria used for data collection and analysis. We aimed to evaluate trends and variation of major/minor amputations, using agreed definitions adopted by the Organization for Economic Cooperation and Development in 2015. Methods: Direct age–sex standardized rates were calculated per 100,000 subjects per year between 2000 and 2013, using major/minor amputations with diabetes diagnosis as numerators and the total population or number of people with diabetes as denominators. Longitudinal trends were investigated using generalized estimating equations. Results: Twenty-one countries reported major amputations referred to the general population, showing a mean reduction from 10.8 to 7.5 per 100,000 (− 30.6%). Eleven countries also reported major amputations among people with diabetes, showing a mean reduction from 182.9 to 128.3 per 100,000 (− 29.8%). Minor amputations remained stable over the study period. Longitudinal trends showed a significant average annual decrease of − 0.19 per 100,000 in the general population (95% CI − 0.36 to − 0.02; p =.03) and − 4.52 per 100,000 among subjects with diabetes (95% CI − 6.09 to − 2.94; p

The management of radioactive waste is a worldwide activity based on the guidelines of the International Atomic Energy Agency (IAEA), and all stages of management require scientifically proven methods for possible deployment. The management of radioactive waste is a huge challenge due to the high risk in the collection, gathering, transport, handling, and storage. In this study, a thermal plasma treatment process was evaluated for its efficiency to process solid radioactive waste. Experiments were carried out with the application of stable isotopes of Lead, Iodine, Cobalt, and Cesium. After the thermal plasma treatments, the slag and the residual gas were analyzed to verify the influence of process time and discharge power on the efficiency of the process. The treatment for 25 min and 10 kW was sufficient to reduce the mass by 50% of the slag. When the applied power was increased to 15 kW, an expressive reduction in the treatment time (10 min) was able to promote the same mass reduction. The results indicated that the treatment of radioactive waste by thermal plasma is a promising method to manage and reduce the mass and volume for the final disposal.

In this paper, we have studied an additively manufactured metallic component, intended for ultra-high vacuum application, the exit-snout of the MACHINA transportable proton accelerator beam-line. Metal additive manufacturing components can exhibit heterogeneous and anisotropic microstructures. Two non-destructive imaging techniques, X-ray computed tomography and Neutron Tomography, were employed to examine its microstructure. They unveiled the presence of porosity and channels, the size and composition of grains and intergranular precipitates, and the general behavior of the spatial distribution of the solidification lines. While X-ray computed tomography evidenced qualitative details about the surface roughness and internal defects, neutron tomography showed excellent ability in imaging the spatial density distribution within the component. The anisotropy of the density was attributed to the material building orientation during the 3D printing process. Density variations suggest the possibility of defect pathways, which could affect high vacuum performances. In addition, these results highlight the importance of considering building orientation in the design for additive manufacturing for UHV applications. Graphical Abstract

The line for the pulsed beam of the 3 MeV Tandetron accelerator at LABEC (Florence) has been upgraded for ion implantation experiments aiming at the fabrication of single-photon emitters in a solid-state matrix. A system based on Al attenuators has been calibrated in order to extend the energy range of the implanted ions from MeV down to the tens of keV. A new motorized XY stage has been installed in the implantation chamber for achieving ultra-fine control on the position of each implanted ion, allowing to reach the scale imposed by lateral straggling. A set-up for the activation of the implanted ions has been developed, based on an annealing furnace operating under controlled high-vacuum conditions. The first experiments have been performed with silicon ions implanted in diamond and the luminescent signal of the silicon-vacancy (SiV) center, peaked at 738 nm, has been observed for a wide range of implantation fluences (108 ÷ 1015 cm−2) and implantation depths (from a few nm to 2.4 µm). Studies on the efficiency of the annealing process have been performed and the activation yield has been measured to range from 1% to 3%. The implantation and annealing facility has thus been tuned for the production of SiV centers in diamond, but is in principle suitable for other ion species and solid-state matrices.

Previous long-term monitorings of the gamma-ray-loud X-ray binary LS I +61{\deg}303 have revealed the presence of a long-term modulation of ~4.5 years. After nine years of simultaneous monitoring of LS I +61{\deg}303 by the Owens Valley Radio Observatory and the Fermi-LAT, two cycles of the long-term period are now available. Here we perform timing-analysis on the radio and the gamma-ray light curves. We confirm the presence of previously detected periodicities at both radio and GeV gamma-ray wavelengths. Moreover, we discover an offset of the long-term modulation between radio and gamma-ray data which could imply different locations of the radio (15 GHz) and GeV emission along the precessing jet., Comment: 8 pages, 7 figures, 2 tables, accepted for publication in MNRAS

LS I +61 degrees 303 is a gamma-ray emitting X-ray binary with periodic radio outbursts with time-scales of one month. Previous observations have revealed microflares superimposed on these large outbursts with periods ranging from a few minutes to hours. This makes LS I +61 degrees 303, along with Cyg X-1, the only TeV emitting X-ray binary exhibiting radio microflares. To further investigate this microflaring activity in LS I +61 degrees 303 we observed the source with the 100-m Effelsberg radio telescope at 4.85, 8.35 and 10.45 GHz, and performed a timing analysis on the obtained data. Radio oscillations of 15 h time-scales are detected at all three frequencies. We also compare the spectral index evolution of radio data to that of the photon index of GeV data observed by Fermi-Large Area Telescope. We conclude that the observed Quasi Periodic Oscillations could result from multiple shocks in a jet.

Ion irradiation is a widely employed tool to fabricate diamond micro- and nano-structures for applications in integrated photonics and quantum optics. In this context, it is essential to accurately assess the effect of ion-induced damage on the variation of the refractive index of the material, both to control the side effects in the fabrication process and possibly finely tune such variations. Several partially contradictory accounts have been provided on the effect of the ion irradiation on the refractive index of single crystal diamond. These discrepancies may be attributable to the fact that in all cases the ions are implanted in the bulk of the material, thus inducing a series of concurrent effects (volume expansion, stress, doping, etc.). Here we report the systematic characterization of the refractive index variations occurring in a 38 µm thin artificial diamond sample upon irradiation with high-energy (3 MeV and 5 MeV) protons. In this configuration the ions are fully transmitted through the sample, while inducing an almost uniform damage profile with depth. Therefore, our findings conclusively identify and accurately quantify the change in the material polarizability as a function of ion beam damage as the primary cause for the modification of its refractive index.

BackgroundData processing of health research databases often requires a Data Protection Impact Assessment to evaluate the severity of the risk and the appropriateness of measures taken to comply with the European Union (EU) General Data Protection Regulation (GDPR). We aimed to define and apply a comprehensive method for the evaluation of privacy, data governance and ethics among research networks involved in the EU Project Bridge Health.MethodsComputerised survey among associated partners of main EU Consortia, using a targeted instrument designed by the principal investigator and progressively refined in collaboration with an international advisory panel. Descriptive measures using the percentage of adoption of privacy, data governance and ethical principles as main endpoints were used for the analysis and interpretation of the results.ResultsA total of 15 centres provided relevant information on the processing of sensitive data from 10 European countries. Major areas of concern were noted for: data linkage (median, range of adoption: 45%, 30%–80%), access and accuracy of personal data (50%, 0%–100%) and anonymisation procedures (56%, 11%–100%). A high variability was noted in the application of privacy principles.ConclusionsA comprehensive methodology of Privacy and Ethics Impact and Performance Assessment was successfully applied at international level. The method can help implementing the GDPR and expanding the scope of Data Protection Impact Assessment, so that the public benefit of the secondary use of health data could be well balanced with the respect of personal privacy.

Background Between 2017-2018, the International Consortium for Health Outcomes Measurement (ICHOM) conducted a targeted study to deliver a standard set of outcome measures in diabetes, including patient reported outcomes. Compared to other conditions, the study faced the challenge of a complex data collection in a highly prevalent multifactorial chronic disease. Methods We conducted a structured systematic review of outcome measures focusing on adults with either Type 1 or Type 2 diabetes, followed by a consensus-driven modified Delphi panel including a multidisciplinary group of academics, health professionals and patient representatives. The applicability of the standard set was explored by collecting external feedback from patients and health professionals worldwide. Results The panel identified an essential set of case-mix characteristics and clinical outcomes, including factors related to diabetes control, acute events, chronic complications, health services and survival that can be regularly measured using routine data and ad hoc data collection. Three validated instruments were recommended for ad-hoc data collection of patient-reported outcomes: the “WHO-5” for psychological wellbeing, the “PAID” for diabetes distress and the “PHQ-9” for depression. The feedback received from members of the panel highlighted substantial challenges with regards to the applicability of the approach at a large scale. Conclusions The standard set recommended for use to monitor, benchmark and improve diabetes care has received strong support from stakeholders involved in the process worldwide. However, substantial challenges remain on how to organize a systematic data collection worldwide, with implications on policy and practice that can equally apply across all areas of chronic care. Prioritization of selected targets may be useful to achieve practical results in the immediate future. Key messages A standard set for the data collection of person-centred outcomes in diabetes has been successfully delivered by ICHOM, including case-mix characteristics, clinical and person reported outcomes. The feedback received from a range of stakeholders highlight implications for policy and practice in the data collection of PROMs for person-centred chronic disease monitoring.

In cases of severe injuries or burns, skin grafts (scaffold) are often necessary skin substitutes. To not harm the patient or the donor, research is necessary to search for heterografts, that are formed by biomaterials and are also biodegradable and bioabsorbable to the human body, as is the case with poly (L-lactic acid) - PLA. However, the natural polymers placed on the skin suffer great degradation in media with large amounts of carbon and water, have little durability due to their low ductility. For the proposal, the graphene oxide (GO) nanocharge and pseudoboehmite (PB) were obtained. It is believed that the nanofillers dispersed in the polymer matrix can improve mechanical properties regarding ductility and tenacity, without losing thermal properties. Subsequently, the hybrid nanocharge dispersion methods were employed to obtain in the poly (L-Lactic Acid) (PLA) matrix, forming the material for the desired scaffold. For this research, injectable specimens of pure PLA, PLA structured with GO nanoparticles, and PLA structured with PB nanoparticles, were manufactured. The microstructural and mechanical characterizations were performed on the specimens, to compare the effect generated by the nanocharges on the bulk material. The results showed that the increase in the concentrations of PB and GO nanofillers showed an increase in tenacity and ductility compared to pure PLA, a property that is desired in the scaffold structure.

AIMS To assess country- and individual-level correlates of psychological outcomes, and differences among countries in the associations of individual characteristics with psychological outcomes among adults with diabetes. METHODS The second Diabetes Attitudes, Wishes and Needs (DAWN2(™) ) study assessed self-reported characteristics of people with diabetes in 17 countries, including 1368 adults with Type 1 diabetes and 7228 with Type 2 diabetes. In each country, a sample of 500 adults, stratified by diabetes type and treatment, completed a questionnaire incorporating the validated WHO-5 wellbeing index, the WHOQOL-BREF, and the five-item Problem Areas in Diabetes Scale, as well as the newly developed Diabetes Impact on Life Dimensions that assessed impact ranging from very positive to very negative, with no impact as the midpoint. Multilevel regression analyses identified significant (P < 0.05) independent correlates of psychological outcomes. RESULTS There were significant variations in all outcomes across countries before adjustment for individual-level factors; adjustment reduced between-country disparities. Worse psychological outcomes were associated with more complications, incidence of hypoglycaemia, hypoglycaemic medication, perceived burden of diabetes, family conflict and experience of discrimination. Better psychological outcomes were associated with higher self-rated health, greater access to diabetes education and healthcare, and more psychosocial support from others. The associations of many factors with the outcomes were mediated by modifiable factors. The association of all factors with the outcomes varied across (interacted with) countries, highlighting the need for country-specific analyses. CONCLUSIONS Improvements in modifiable risk factors (reductions in burden and increases in support) may lead to better psychological outcomes in adults with diabetes.

Background The EU-funded Marie Curie project HEALTHPROS aims to foster a new generation of “Healthcare Performance Intelligence Professionals” through a cohesive stream of 13 doctoral projects (www.healthpros-h2020.eu). Over 48 months, researchers will investigate key levers of healthcare improvement in 7 different countries, using methods drawn from the diverse fields of biostatistics, medical informatics and health services research. Objectives To describe barriers and enablers in the conduction of two doctoral projects aimed at exploring the impact of personal risk factors and organizational arrangements on lower extremity amputations in diabetes, through the use of large-scale databases from England, Scotland, Denmark and Germany. Results The research plan included a systematic review, structured comparison of data sources, predictive modelling and software development for automated international comparisons. Barriers encountered by researchers were: knowledge and access to data sources from different countries, dealing with data protection rules and the ability to carry out international comparisons when individual records are not easily allowed to leave national boundaries. Enabling factors included: a targeted educational process for risk modelling in diabetes and a multidisciplinary support team to help doctoral students overcoming the above barriers across different sites. Further clinical insight and contextual knowledge of data systems in place at different locations were needed in addition to the statistical, epidemiological and technical skills initially foreseen by the program. Conclusions The success of studies within a general educational program on health systems performance may depend from the continued support of a multidisciplinary team helping students in their educational process as well as with the practicalities of their research. International comparisons using routine data may require prioritisation to meet the tight timelines of doctoral theses. Key messages Academic programs for international comparisons in health care may be hampered by different type of barriers including technical aspects, legal regulations and a range of contextual factors. The establishment of multidisciplinary support teams may be essential for training doctoral students aiming to conduct international comparisons using routine data.

Table S1. Distribution of demographic variables and risk factors according to the type of work among health-care workers. (DOCX 26 kb)

Table S2. Serological profile of HBV infection among health-care workers according to hepatitis B vaccination status. (DOCX 21 kb)

Chronic pain is common after groin hernia surgery, affecting approximately 10% of patients. The type of anesthesia has been shown to affect short term pain (within 30 days) where Local Anesthesia ( ...

Recently, developments have been made to the external scanning microbeam of INFN-LABEC laboratory in Florence. A new system for mechanical sample scanning was implemented. This system allows us to acquire large maps (up to 20 × 20 cm 2 ), of great interest in the Cultural Heritage field. In parallel, the possibility of using carbon microbeams for experiments, such as, for example, ion beam modification of materials and MeV Secondary Ion Mass Spectrometry, has been investigated. As a test application, Particle Induced X-ray Emission with carbon microbeams has been performed on a lapis lazuli stone. First results for both wide area imaging and external carbon microbeams are briefly reported.

In the last few years some new implementations and upgrades have been made to the external scanning microbeam of INFN-LABEC laboratory in Florence, enriching the existing PIXE, PIGE, BS, IBIL set-up with complementary techniques, when possible allowing for simultaneous multi-technique analyses. We developed a system, compatible with the existing set-up, for the out-of-vacuum detection of the forward scattered particles. This system makes feasible the external-STIM (Scanning Transmission Ion Microscopy) and external-FS (Forward Scattering), now both available at our beamline. Test measurements are shortly presented.

Background: Many melanoma observational studies have been carried out across different countries and geographic areas using heterogeneous assessments of epidemiologic risk factors and clinical variables. Aim: To develop a consensus questionnaire to standardize epidemiologic and clinical data collection for melanoma risk assessment. Methods: We used a stepwise strategy that included: compilation of variables from case–control datasets collected at various centres of the MelaNostrum Consortium; integration of variables from published case–control studies; consensus discussion of the collected items by MelaNostrum members; revision by independent experts; addition of online tools and image-based charts; questionnaire testing across centres and generation of a final draft. Results: We developed a core consensus questionnaire (MelanoQ) that includes four separate sections: A. general and demographic data; B. phenotypic and ultraviolet radiation exposure risk factors and lifestyle habits; C. clinical examination, medical and family history; and D. diagnostic data on melanoma (cases only). Accompanying online tools, informative tables, and image-based charts aid standardization. Different subsections of the questionnaire are designed for self-administration, patient interviews performed by a physician or study nurse, and data collection from medical records. Conclusions: The MelanoQ questionnaire is a useful tool for the collection and standardization of epidemiologic and clinical data across different studies, centres, cultures and languages. This will expedite ongoing efforts to compile high-quality data for pooled analyses or meta-analyses and offer a solid base for the design of clinical, epidemiologic and translational studies on melanoma. © 2018 European Academy of Dermatology and Venereology

Li2SnS3 is a fast Li+ ion conductor that exhibits high thermal stability (mp ∼750 °C) as well as environmental stability under ambient conditions. Polycrystalline Li2SnS3 was synthesized using high-temperature, solid-state synthesis. According to single-crystal X-ray diffraction, Li2SnS3 has a sodium chloride-like structure (space group C2/c), a result supported by synchrotron X-ray powder diffraction and 119Sn Mossbauer spectroscopy. According to impedance spectroscopy, Li2SnS3 exhibits Li+ ion conductivity up to 1.6 × 10–3 S/cm at 100 °C, which is among the highest for ternary chalcogenides. First-principles simulations of Li2SnS3 and the oxide analogue, Li2SnO3, provide insight into the basic properties and mechanisms of the ionic conduction. The high thermal stability, significant lithium ion conductivity, and environmental stability make Li2SnS3 a promising new solid-state electrolyte for lithium ion batteries.

The primary aim of this study was to examine the effects of intensive periodontal therapy on HbA(1c) in a mixed diabetes mellitus (DM) (types 1 and 2) population with moderate periodontitis (PD).A total of 93 subjects with PD and DM, recruited from referrals to the Department of Endocrinology at the Perugia Hospital, were included in a follow-up cohort clinical study comprising two parallel periodontal therapy groups-one receiving intensive periodontal therapy (IPT, n=44) and the other serving as controls (CPT, n=49)-with an 8-month follow-up. Clinical periodontal examinations and blood samples were collected 4 and 8 months after the completion of therapy.The IPT group presented with greater reductions of all periodontal indices compared with the CPT group at both follow-ups (P0.001). Whereas, after 4 months, there were no major differences in HbA(1c) levels between groups, after 8 months, the IPT group presented with a 0.57% (95% CI: 0.12 to 1.09) greater reduction in HbA(1c) than the CPT group (P=0.03). This reduction was independent of age, gender, smoking and body mass index. However, the difference in HbA(1c) was greater in individuals with type 2 DM (0.95% reduction, 95% CI: 0.32 to 1.58; P=0.004) compared with those with type 1 DM.IPT resulted in greater improvement of gingival health in patients with DM. Improved oral health in those with type 2 DM may have an effect on medium-term glucose management and could possibly lead to long-term health benefits. (ISRCTN00559156).

OBJECTIVES: To foster the development of a privacy-protective, sustainable cross-border information system in the framework of a European public health project. MATERIALS AND METHODS: A targeted privacy impact assessment was implemented to identify the best architecture for a European information system for diabetes directly tapping into clinical registries. Four steps were used to provide input to software designers and developers: a structured literature search, analysis of data flow scenarios or options, creation of an ad hoc questionnaire and conduction of a Delphi procedure. RESULTS: The literature search identified a core set of relevant papers on privacy (n = 11). Technicians envisaged three candidate system architectures, with associated data flows, to source an information flow questionnaire that was submitted to the Delphi panel for the selection of the best architecture. A detailed scheme envisaging an "aggregation by group of patients" was finally chosen, based upon the exchange of finely tuned summary tables. CONCLUSIONS: Public health information systems should be carefully engineered only after a clear strategy for privacy protection has been planned, to avoid breaching current regulations and future concerns and to optimise the development of statistical routines. The BIRO (Best Information Through Regional Outcomes) project delivers a specific method of privacy impact assessment that can be conveniently used in similar situations across Europe.

Ion beam analysis (IBA) techniques are often used to study works of art, mainly for their non-destructive character. In these techniques, products of interactions between beams and targets are exploited to determine the elemental composition of the sample surface down to depths from few micrometres to hundreds of micrometres, depending on incident particles, their energy and target material.For samples with surface inhomogeneities, information about elemental distribution can be essential to discriminate contributions from different areas. At the authors’ laboratory in Florence (LABEC), the external scanning proton microprobe facility — installed on a beam line of the 3 MV Tandem Accelerator — allows samples to be analysed in atmosphere, with spatial resolution down to around micrometres, and to extract elemental maps from the investigated areas.Recently, there has been the opportunity of analysing a ‘gold lace embroidery’ (using silk threads, spiral wrapped by a sort of miniature golden tape) aft...

In order to directly study the role of magnetic fields in the immediate vicinity of protostars, we use Very-Long-Baseline Interferometry (VLBI), aiming at the detection of non-thermal centimetric radio emission. This is technically the only possibility to study coronal emission at sub-AU resolution. We performed VLBI observations of the four nearby protostars HL Tau, LDN 1551 IRS5, EC 95, and YLW 15 in order to look for compact non-thermal centimetric radio emission. For maximum sensitivity, we used the High Sensitivity Array (HSA) where possible, involving the Very Long Baseline Array (VLBA), the phased Very Large Array (VLA), as well as the Arecibo, Green Bank, and Effelsberg radio telescopes. While all four protostars were detected in VLA-only data, only one source (YLW 15 VLA 2) was detected in the VLBI data. The possibility of non-detections due to free-free absorption, possibly depending on source geometry, is considered. For YLW 15 VLA 2, the prospects for an accurate orbit determination appear to be good., 8 pages, 4 figures, accepted for publication in A&A