Searching for magnetic monopoles trapped in accelerator material at the Large Hadron Collider

If produced in high energy particle collisions at the LHC, magnetic monopoles could stop in material surrounding the interaction points. Obsolete parts of the beam pipe near the CMS interaction region, which were exposed to the products of pp and heavy ion collisions, were analysed using a SQUID-based magnetometer. The purpose of this work is to quantify the performance of the magnetometer in the context of a monopole search using a small set of samples of accelerator material ahead of the 2013 shutdown.Comment: 11 page

Counter-intuitive evaporation in nanofluids droplets due to stick-slip nature

We experimentally investigate the evaporation characteristics of a sessile ethanol droplet containing Al$_2$O$_3$ and Cu nanoparticles of sizes 25 nm and 75 nm on a heated substrate using shadowgraphy and infrared imaging techniques. Our results demonstrate that the droplet contact line dynamics resulting from the presence of various nanoparticles plays a dominant role in the evaporation process. This is in contrast to the widely-held assumption that the enhanced evaporation rate observed in sessile nanofluid droplets is due to the higher thermal conductivity of the added nanoparticles. We observe that even though the thermal conductivity of Al$_2$O$_3$ is an order of magnitude lower than that of Cu, droplets containing 25 nm-sized Al$_2$O$_3$ exhibit pinned contact line dynamics and evaporate much more rapidly than droplets containing Cu nanoparticles of both sizes and 75 nm Al$_2$O$_3$ nanoparticles that exhibit stick-slip behaviour. We also found that the droplets with different nanoparticles display distinct thermal patterns due to the difference in contact line behaviour, which alters the heat transfer inside the droplets. We establish this counter-intuitive observation by analysing the temporal variations of the perimeter, free surface area, and deposition patterns on the substrate.Comment: 30 pages, 7 figures, Journal-Langmui

Services and support for mothers and newborn babies in vulnerable situations: A study of eight European jurisdictions

European countries have a legal obligation to provide services to vulnerable families, and children must not be removed from their parents’ care unless no other viable measures are available. This paper examines whether and how eight jurisdictions provide necessary support and services to families with newborn babies who are considered to be at risk in the child protection system. The data consist of all judgments (n = 216) concerning care orders for 220 newborns for periods ranging from one to several years. The analysis shows that services are provided in an overall majority of the cases but with distinct differences between jurisdictions. These differences are not due to the type of child protection system. Furthermore, we cannot ascertain whether service provision follows parental problems, or identify similarities due to the special case of newborns. We conclude that there are huge knowledge gaps regarding both service provision and the effects of services.publishedVersio

Sustainability of community-owned mini-grids: Evidence from India

open access journalBackground: Community-owned Solar Mini-Grids (SMGs) are increasingly promoted to provide communities access to reliable electricity, empowering local actors as they become active stakeholders in projects. However, early failures and difficulties in building local capacity have raised questions regarding their long-term sustainability and ability to be replicated to provide socio-economic benefits to the communities. This study assesses the sustainability of 24 community-owned SMGs in India operating over extensive periods of time using a novel scoring framework using mixed methods to derive its conclusions. Results: The study found that institutional, financial and technical capacities, central for the SMG’s long-term sustainability, could be achieved through community engagement from early stages, if communities are allowed freedom to develop governance procedures while at the same time clarifying roles and responsibilities. This creates strong sense of ownership that is key for effective and inclusive governance. User satisfaction, ensured through provision of usable supply in line with users’ expectations, motivates actors to make regular payments, thus leading to economic sustenance. While social and environmental benefits were observed, energy consumption and engagement in productive activities remained marginal. Conclusions: The study reports an example of community-owned SMG model that has been replicated sustainably over many cases, overcoming key challenges related to appropriate financial and technical management and producing positive social impact. Low engagement in productive activities was more a factor of the local socio-cultural contexts, rather than limited paying capacities of the users. To increase energy utilization and create environments for sustainable rural living the study recommends implementation of systems that link energy with other rural development needs such as agriculture or water provision. The study also recommends more use of qualitative and quantitative data for impact analysis to ensure that conclusions are generalizable and provide rich contextual explanations for the observed phenomena

First-principles determination of the phonon-point defect scattering and thermal transport due to fission products in ThO2

This work presents the first principles calculations of the lattice thermal conductivity degradation due to point defects in thorium dioxide using an alternative solution of the Pierels-Boltzmann transport equation. We have used the non-perturbative Green's function methodology to compute the phonon point defect scattering rates that consider the local distortion around the point defect, including the mass difference changes, interatomic force constants and structural relaxation near the point defects. The point defects considered in the work include the vacancy of thorium and oxygen, substitution of helium, krypton, zirconium, iodine, xenon, in the thorium site, and the three different configuration of the Schottky defects. The results of the phonon-defect scattering rate reveals that among the considered intrinsic defects, the thorium vacancy and helium substitution in the thorium site scatter the phonon most due to substantial changes in the force constant and structural distortions. The scattering of phonons due to the substitutional defects unveils that the zirconium atom scatters phonons the least, followed by xenon, iodine, krypton, and helium. This is contrary to the intuition that the scattering strength follows HeTh > KrTh > ZrTh > ITh > XeTh based on the mass difference. This striking difference in the zirconium phonon scattering is due to the local chemical environment changes. Zirconium is an electropositive element with valency similar to thorium and, therefore, can bond with the oxygen atoms, thus creating less force constant variance compared to iodine, an electronegative element, noble gas helium, xenon, and krypton. These results can serve as the benchmark for the analytical models and help the engineering-scale modeling effort for nuclear design.Comment: 10 page

Iodine status during pregnancy in India and related neonatal and infant outcomes

Objective: To document iodine status in Indian pregnancies, associations with maternal diet and demographics, and offspring developmental measures. Design: Longitudinal study following mothers through pregnancy and offspring up to 24 months. Setting: Rural health-care centre (Vadu) and urban antenatal clinic (Pune) in the Maharashtra region of India. Subjects: Pregnant mothers at 17 (n 132) and 34 weeks’ (n 151) gestation and their infants from birth to the age of 24 months. Results: Median urinary iodine concentration (UIC) was 203 and 211 μg/l at 17 and 34 weeks of pregnancy, respectively (range 26–800 μg/l). Using the UIC distribution adjusted for within-person variation, extreme UIC quartiles were compared for predictors and outcomes. There was no correlation between UIC at 17 and 34 weeks, but 24 % of those with UIC in the lowest quartile at 17 weeks had UIC in the same lowest quartile at 34 weeks. Maternal educational, socio-economic status and milk products consumption (frequency) were different between the lowest and highest quartile of UIC at 34 weeks. Selected offspring developmental outcomes differed between the lowest and highest UIC quartiles (abdominal circumference at 24 months, subscapular and triceps skinfolds at 12 and 24 months). However, UIC was only a weak predictor of subscapular skinfold at 12 months and of triceps skinfold at 24 months. Conclusions: Median UIC in this pregnant population suggested adequate dietary provision at both gestational stages studied. Occasional high results found in spot samples may indicate intermittent consumption of iodine-rich foods. Maternal UIC had limited influence on offspring developmental outcomes

High-spin spectroscopy in 207^{207}At: Evidence of a 29/2+^{+} isomeric state

Yrast and near-yrast states above the known 25/2$^{+}$ isomer in $^{207}$At are established for the first time. The level scheme is extended up to 47/2$\hbar$ and 6.5 MeV with the addition of about 60 new $\gamma$-ray transitions. The half-life of the 25/2$^{+}$ isomer is revisited and a value of $T_{1/2}$ = 107.5(9) ns is deduced. Evidence of a hitherto unobserved 29/2$^{+}$ isomer in $^{207}$At is presented. A systematic study of $B(E3)$ values for the transitions de-exciting the 29/2$^{+}$ isomer in the neighboring odd-$A$ At isotopes suggests a half-life in the 2$-$4 $\mu$s range for this state in $^{207}$At. The experimental results are compared with large-scale shell-model calculations performed using the KHM3Y effective interaction in the $Z$ = 50$-$126, $N$ = 82$-$184 model space and an overall good agreement is noted between the theory and the experiment. A qualitative comparison of the excited states and the isomers with analogous states in neighboring nuclei provides further insight into the structure of $^{207}$At.Comment: 15 pages, 13 figure