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In this paper we adapt the nearest neighbour rule to the contextual bandit problem. Our algorithm handles the fully adversarial setting in which no assumptions at all are made about the data-generation process. When combined with a sufficiently fast data-structure for (perhaps approximate) adaptive nearest neighbour search, such as a navigating net, our algorithm is extremely efficient - having a per trial running time polylogarithmic in both the number of trials and actions, and taking only quasi-linear space.

En este trabajo se analiza la convergencia económica de los departamentos de Mendoza durante el período 1996 a 2012. Se examina la evolución de las desigualdades territoriales mediante indicadores de disparidad, dispersión y brechas de crecimiento. No se encuentran evidencias de un proceso de convergencia territorial. El coeficiente β estimado resulta positivo y estadísticamente no significativo; el Coeficiente de Williamson, σ-convergencia y brechas de crecimiento revelan un leve aumento de la desigualdad, especialmente durante períodos de auge. Tampoco se encontró evidencia de relación positiva entre crecimiento y especialización agropecuaria. La inserción internacional del sector agroindustrial no contribuyó a mejorar significativamente la situación de los territorios fuertemente agropecuarios, los de menor desarrollo relativo provincial.

The rapid development of network function virtualization (NFV) enables a communication network to provide in-network services using virtual network functions (VNFs) deployed on general IT hardware. While existing studies on NFV focused on how to provision VNFs from the provider’s perspective, little is done about how to validate the provisioned resources from the user’s perspective. In this work, we take a first step towards this problem by developing an inference framework designed to “look into” the NFV network. Our framework infers the structure and state of the overlay formed by VNF instances, ingress/egress points of measurement flows, and critical points on their paths (branching/joining points). Our solution only uses external observations such as the required service chains and the end-to-end performance measurements. Besides the novel application scenario, our work also fundamentally advances the state of the art on topology inference by considering (i) general topologies with general measurement paths, and (ii) information of service chains. Our evaluations show that the proposed solution significantly improves both the reconstruction accuracy and the inference accuracy over existing solutions, and service chain information is critical in revealing the structure of the underlying topology.

Geobiologists attempt to answer such questions as: when and under what conditions did life begin, how can we verify biogenicity in the geologic record, and what governs the relation between the living world and the mineral world? Raman spectroscopy can characterize and identify both organic and inorganic phases, typically nondestructively, at the (sub-)micrometer scale and, thereby, can provide key information to tackle these questions. This article illustrates contributions that Raman spectroscopy has made to understanding mineralization processes in mollusks, corals, and bones. Raman spectroscopy can also be used in the search for earliest terrestrial life and life on other planets. Some challenges for the three Raman instruments to be deployed on Mars are discussed.

Geoscientists quickly recognized the broad applicability of Raman micro-probe spectroscopy to the Earth and planetary sciences, especially after commercially built microprobe instruments became available in the early 1980s. Raman spectra are sensitive to even minor (chemical or structural) perturbations within chemical bonds in (even amorphous) solids, liquids, and gases and can, thus, help identify, characterize, and differentiate between individual minerals, fluid inclusions, glasses, carbonaceous materials, solid solution phases, strain in minerals, and dissolved species in multi-component solutions. The articles in this issue explore how Raman spectroscopy has deepened and broadened our understanding of geological and extraterrestrial materials and processes.

Adsorbed and structurally incorporated carbonate in bioapatite, the primary mineral phase of bone, is observed across vertebrates, typically at 2–8 wt%, and supports critical physiological and biochemical functions. Several turtle species contain elevated bone-associated carbonate, a property linked to pH buffering and overwintering survival. Prior studies of turtle bone utilized bulk analyses, which do not provide spatial resolution of carbonate. Using Raman spectroscopy, the goals of this study were to: (1) quantify and spatially resolve carbonate heterogeneity within the turtle shell; (2) determine if cortical and trabecular bone contain distinct carbonate concentrations; and (3) assess if simulated overwintering conditions result in decreased bioapatite carbonation. Here, we demonstrate the potential for Raman spectroscopic analysis to spatially resolve bioapatite carbonation, using the western painted turtle as a model species. Carbonate concentration was highly variable within cortical and trabecular bone, based on calibrated Raman spot analyses and mapping, suggesting heterogeneous carbonate distribution among crystallites. Mean carbonate concentration did not significantly differ between cortical and trabecular bone, which indicates random distribution of crystallites with elevated and depleted carbonate. Carbonate concentrations (range: 5–22 wt%) were not significantly different in overwintering and control animals, deviating from previous bulk analyses. In reconciling bulk and Raman analyses, two hypotheses explain how overwintering turtles potentially access carbonate: (1) mobilization of mineral-associated, surface components of bone crystallites; and (2) selective, dispersed crystallite dissolution. Elevated bioapatite carbonate in the western painted turtle, averaging 11.8 wt%, represents the highest carbonation observed in vertebrates, and is one physiological trait that facilitates overwintering survival.

La utilización de las promociones de precios en los mercados minoristas es reconocida como una práctica habitual. Su uso reciente durante los últimos años ha propiciado que desde la teoría de marketing se haya propuesto una serie de enfoques que buscan explicar sus motivos y efectos económicos. En el caso de Mendoza (Argentina), investigaciones empíricas previas sobre la conducta de los grandes minoristas multiproducto demuestran que estas promociones son una práctica generalizada. El objetivo de este trabajo es presentar un modelo que permita explicar la racionalidad de esta conducta de los minoristas multiproducto, demostrada empíricamente. La propuesta supone consumidores parcialmente informados y con expectativas racionales. También se propone este modelo como marco teórico para constatar, en próximas investigaciones, su pertinencia cuando la competencia minorista se desarrolla con Internet como canal de venta. Price promotions in retail markets are recognized as a common practice. Its increasing use in recent years has meant that a number of approaches that seek to explain their motives and economic effects have been proposed. In the case of Mendoza, Argentina, previous empirical research on the behavior of large multiproduct retailers proved that these promotions are widely used. The aim of this paper is to present a model that explains the rationality of multiproduct retailers promotions, proved empirically. Partially informed and rational expectations consumers are supposed. This model is also proposed as a theoretical framework for testing its relevance in future research when competition is by internet as a sales channel. &nbsp

The musculoskeletal system is sensitive to its loading environment; this is of particular concern under conditions such as disuse, paralysis, and extended-duration space flight. Although structural and mechanical changes to tendon and bone following paralysis and disuse are well understood, there is a pressing need to understand how this unloading affects the bone-tendon interface (enthesis); the location most prone to tears and injury. We therefore elucidated these effects of unloading in the entheses of adult mice shoulders that were paralyzed for 21 days by treatment with botulinum toxin A. Unloading significantly increased the extent of mechanical failure and was associated with structural changes across hierarchical scales. At the millimeter scale, unloading caused bone loss. At the micrometer scale, unloading decreased bioapatite crystal size and crystallographic alignment in the enthesis. At the nanometer scale, unloading induced compositional changes that stiffened the bioapatite/collagen composite tissue. Mathematical modeling and mechanical testing indicated that these factors combined to increase local elevations of stress while decreasing the ability of the tissue to absorb energy prior to failure, thereby increasing injury risk. These first observations of the multiscale effects of unloading on the adult enthesis provide new insight into the hierarchical features of structure and composition that endow the enthesis with increased resistance to failure. Statement of Significance The musculoskeletal system is sensitive to its loading environment; this is of particular concern under conditions such as disuse, paralysis, and extended-duration space flight. Although changes to tendon and bone following paralysis are understood, there is a pressing need to clarify how unloading affects the bone-tendon interface (enthesis), which is the location most prone to tears and injury. We elucidated the effects of enthesis unloading in adult mice shoulders showing, for the first time, that unloading significantly increased the risk and extent of mechanical failure and was associated with structural changes across hierarchical scales. These observations provide new insight into the hierarchical features of structure and composition that endow the enthesis with resilience. This knowledge can be used to develop more targeted treatments to improve mobility and function.

The profitability of commercial pig farms largely depends on the reproductive performance of gilts and sows. The aim of this study was to identify differences in the composition and diversity of vaginal microbiota between gilts (G) and pregnant (P) sows, both artificially inseminated (AI) and natural mating (NM). Samples were collected by scraping the vaginal mucosa of G (n = 10) and P (NM, n = 10 and AI, n = 7) sows. Samples were analysed by culture-dependent techniques and 16S-rRNA gene High-Throughput-Sequencing. The profiles of the cultured microbiota showed two distinctive clusters, one of them grouped four samples of P sows from the AI group. The vaginal microbiota from P had lower richness than G sows (Mann-Whitney/Kruskal-Wallis test, p 0.01), but all vaginal samples had a similar diversity. The PERMANOVA analyses revealed significant differences (p 0.01) between the microbial communities' structures from G and P sows. The bacteria phyla with the highest relative abundances were Proteobacteria (33.1%), followed by Firmicutes (32%), Cyanobacteria (13.3%) and Actinobacteria (13.2%). The relative abundance for phyla, families and genera was estimated and Proteobacteria was significantly higher (p = 0.038) in P than in G sows; Firmicutes was significantly lower in AI than G and NM sows. A "core microbiota" included Lactobacillus, Bacillus, Enterococcus, Acinetobacter and Pseudomonas. The results presented highlight the differences in the bacterial composition between G and P sows, as well as the changes in the microbial populations associated with the breeding method.

Purpose Helical Tomotherapy (HT) appears as a valuable technique for total body irradiation (TBI) to create highly homogeneous and conformal dose distributions with more precise repositioning than conventional TBI techniques. The aim of this work is to describe the technique implementation, including treatment preparation, planning and dosimetric monitoring of TBI delivered in our institution from October 2016 to March 2019. Material and method Prior to patient care, irradiation protocol was set up using physical phantoms. Gafchromic films were used to assess dose distribution homogeneity and evaluate imprecise patient positioning impact. Sixteen patients’ irradiations with a prescribed dose of 12 Gy were delivered in 6 fractions of 2 Gy over 3 days. Pre-treatment quality assurance (QA) was performed for the verification of dose distributions at selected positions. In addition, in-vivo dosimetry was carried out using optically stimulated luminescence dosimeters (OSLD). Results Planning evaluation, as well as results of pre-treatment verifications, are presented. In-vivo dosimetry showed the strong consistency of OSLD measured doses. OSLD mean relative dose differences between measurement and calculation were respectively +0,96% and −2% for armpit and hands locations, suggesting better reliability for armpit OSLD positioning. Repercussion of both longitudinal and transversal positioning inaccuracies on phantoms is depicted up to 2 cm shifts. Conclusion The full methodology to set up TBI protocol, as well as dosimetric evaluation and pre-treatment QA, were presented. Our investigations reveal strong correspondence between planned and delivered doses shedding light on the dose reliability of OSLD for HT based TBI in-vivo dosimetry.

We introduce a novel online multitask setting. In this setting each task is partitioned into a sequence of segments that is unknown to the learner. Associated with each segment is a hypothesis from some hypothesis class. We give algorithms that are designed to exploit the scenario where there are many such segments but significantly fewer associated hypotheses. We prove regret bounds that hold for any segmentation of the tasks and any association of hypotheses to the segments. In the single-task setting this is equivalent to switching with long-term memory in the sense of [Bousquet and Warmuth; 2003]. We provide an algorithm that predicts on each trial in time linear in the number of hypotheses when the hypothesis class is finite. We also consider infinite hypothesis classes from reproducing kernel Hilbert spaces for which we give an algorithm whose per trial time complexity is cubic in the number of cumulative trials. In the single-task special case this is the first example of an efficient regret-bounded switching algorithm with long-term memory for a non-parametric hypothesis class.

For lead pipes that contain PbO2(s) as a major component of their scales, a change in the residual disinfectant from free chlorine to monochloramine can destabilize the PbO2(s) and result in dramatic increases in aqueous lead concentrations. Such a scenario occurred in Washington, D.C., in late 2000. That problem was ultimately addressed by the addition of phosphate as a corrosion inhibitor, but it took several months for lead levels to drop below regulatory values. This study sought to determine whether adding phosphate prior to switching the disinfectant could mitigate lead release. Using synthetic tap water and new lead pipes, we developed a set of lead pipes with scales rich in PbO2(s) and then studied their response to a change from free chlorine to monochloramine. Total lead concentrations remained below 10 μg/L for pipes that received phosphate prior to and during the switch. In contrast, total lead concentrations increased from less than 5 μg/L to more than 150 μg/L as a result of the disinfectant switch when phosphate was not present. Characterization of the pipe scales demonstrated that plattnerite (β-PbO2(s)) was the dominant component of the scale prior to the switch, and that the scale gradually transformed into one containing a lead phosphate solid chemically similar to phosphohedyphane (Ca2Pb3(PO4)3(Cl,F,OH)(s)) when phosphate was present.

This study explored the ability of orthophosphate addition to limit lead release from lead service lines delivering high pH, low alkalinity water. We built pipe loop reactors with lead pipes harvested from Providence, RI, and we operated them with high pH and low alkalinity water of a composition similar to that in Providence. Orthophosphate addition decreased the release of both dissolved and particulate lead to the water. The most substantial decreases in total lead concentrations occurred after 15 weeks of orthophosphate addition, which was associated with the formation of calcium-lead-phosphorus (Ca-Pb-P) solids as part of the pipe scale. Pre-existing hydrocerussite (Pb3(CO3)2(OH)2(s)) in the scale of the lead pipe appeared to promote the formation of a Ca-Pb-P solid similar to phosphohedyphane (Ca2Pb3(PO4)3(Cl,F,OH)(s)). Continuous orthophosphate addition was also associated with the formation of a calcium phosphate solid with features like those of fluorapatite (Ca5(PO4)3F(s)) on the outermost layer of the scale. Through promoting the formation of these new solids within and on top of the scales, orthophosphate addition limited release of dissolved and particulate lead. These results demonstrate the ability of orthophosphate to control lead release at higher pH conditions than those for which it has typically been used. In addition to the formation of phosphate solids, PbO2(s), which was not present on the as-received pipes, was formed due to the constant supply of free chlorine in the laboratory-scale experiment.

Phosphate is added to Pb-contaminated soils to induce lead immobilization through lead phosphate precipitation. Organic coatings on soils, which may affect heterogeneous lead phosphate nucleation, can impact the effectiveness of lead immobilization. Here, SiO2 surfaces were coated with silanol self-assembled thin films terminated with −COOH and −OH functional groups to act as model organic coatings on soil particles. Using grazing incidence small-angle X-ray scattering (GISAXS), heterogeneous lead phosphate nucleation on coatings was measured from mixed Pb(NO3)2 and Na2HPO4/NaH2PO4 solutions at pH 7 with varied ionic strengths (IS = 0.58, 4, and 11 mM). Raman spectroscopy identified the homogeneous precipitates in solution as hydroxylpyromorphite (Pb5(PO4)3OH). The smallest lead phosphate nuclei (4.5 ± 0.5 nm) were observed on −COOH coatings, which resulted from the highest level of lead and phosphate ion adsorption on −COOH coatings. The IS of the solution also affected the sizes of the heterogeneous pre...

Si bien el crecimiento económico de un territorio se mide a través de la evolución de su Producto Bruto Geográfico per cápita, el impacto sobre el bienestar de la población se evalúa, entre otras variables, por la capacidad de este crecimiento de generar demanda de empleo de calidad. Algunos territorios sub-nacionales presentan una parte de su actividad económica con determinantes autónomos, que los hace independizarse, al menos parcialmente, de los ciclos nacionales. Ciertas políticas públicas sectoriales apuntan a conseguir estos resultados.

In view of the potential use of pyrolysis-based technologies, it is crucial to understand the environmental hazards of pyrolysis-derived products, in particular bio-oils. Here, three bio-oils were produced from fast pyrolysis of pine wood and intermediate pyrolysis of corn stalk and poultry litter. They were fully characterized by chemical analysis and tested for their biodegradability and their ecotoxicity on the crustacean Daphnia magna and the green alga Raphidocelis subcapitata. These tests were chosen as required by the European REACH regulation. These three bio-oils were biodegradable, with 40-60% of biodegradation after 28 days, and had EC50 values above 100mgL(-1) for the crustacean and above 10mgL(-1) for the alga, showing low toxicity to the aquatic life. The toxic unit approach was applied to verify whether the observed toxicity could be predicted from the data available for the substances detected in the bio-oils. The predicted values largely underestimated the experimental values.

Reconstruction of past changes in Arctic sea ice extent may be critical for understanding its future evolution. Methanesulfonate (MSA) and bromine concentrations preserved in ice cores have both been proposed as indicators of past sea ice conditions. In this study, two ice cores from central and north-eastern Greenland were analysed at sub-annual resolution for MSA (CH3SO3H) and bromine, covering the time period 1750–2010. We examine correlations between ice core MSA and the HadISST1 ICE sea ice dataset and consult back trajectories to infer the likely source regions. A strong correlation between the low-frequency MSA and bromine records during pre-industrial times indicates that both chemical species are likely linked to processes occurring on or near sea ice in the same source regions. The positive correlation between ice core MSA and bromine persists until the mid-20th century, when the acidity of Greenland ice begins to increase markedly due to increased fossil fuel emissions. After that time, MSA levels decrease as a result of declining sea ice extent but bromine levels increase. We consider several possible explanations and ultimately suggest that increased acidity, specifically nitric acid, of snow on sea ice stimulates the release of reactive Br from sea ice, resulting in increased transport and deposition on the Greenland ice sheet.

Biomaterials are synthetic compounds and composites that replace or assist missing or damaged tissue or organs. This review paper addresses Ca phosphate biomaterials that are used as aids to or substitutes for bones and teeth. The viewpoint taken is that of mineralogists and geochemists interested in (carbonated) hydroxylapatite, its range of compositions, the conditions under which it can be synthesized, and how it is used as a biomaterial either alone or in a composite. Somewhat counter-intuitively, the goal of most medical or materials science researchers in this field is to emulate the properties of bone and tooth, rather than the hierarchically complex materials themselves. The absence of a directive to mimic biological reality has permitted the development of a remarkable range of approaches to apatite synthesis and post-synthesis processing. Multiple means of synthesis are described from low-temperature aqueous precipitation, sol-gel processes, and mechanosynthesis to high-temperature solid-state reactions and sintering up to 1000 °C. The application of multiple analytical techniques to characterize these apatitic, frequently nanocrystalline materials is discussed. An online supplement 1 details the specific physical and chemical forms in which synthetic apatite and related Ca phosphate phases are used in biomaterials. The implications from this overview are the enhanced recognition of the structurally and chemically accommodating nature of the apatite phase, insight into the effects of synthesis techniques on the specific properties of minerals (specifically apatite), and the importance of surface chemistry of apatite nanocrystals. The wide range of synthesis techniques, types of analytical characterization, and applications to human health associated with apatite are a non-geological demonstration of the power of mineralogy.

Resume Propos L’amelioration des traitements des cancers de l’enfant a permis une augmentation de la survie a 80 % a 5 ans. La radiotherapie, parfois indispensable au traitement, est associee a des effets indesirables a long terme. L’objectif de cette etude etait d’analyser les complications a long terme de patients ayant eu un cancer dans l’enfance et traite par radiotherapie. Methodes L’etude SALTO, basee sur les registres de cancers de l’enfant en Rhone-Alpes-Auvergne, concernait les enfants traites pour un cancer solide ou un lymphome avant 15 ans, diagnostique entre 1987 et 1992, et majeurs au moment de l’etude. Une consultation par un oncopediatre et un interniste a ete proposee entre 2011 et 2014. Les enfants traites par radiotherapie ont ete compares aux patients traites sans irradiation. Les sequelles ont ete classees en moderees (grade 1–2) ou severes (grade 3–4) selon la CTCAE. Resultats Cinquante-neuf patients ayant recu de la radiotherapie ont participe a ces consultations et 91 sans radiotherapie. Cinquante-huit patients avec radiotherapie (98,3 %) ont presente au moins une complication. Les principaux effets secondaires a long terme tous grades confondus etaient orthopediques (37 %), endocriniens (32 %), thyroidiens (31 %) et l’obesite (31 %). Les principales complications de grade 3–4 etaient endocriniennes, renales, une obesite et les cancers secondaires. On retrouvait significativement plus de complications endocriniennes, thyroidiennes, orthopediques, cutanees, de surdite et de cancers secondaires chez les patients irradies compares aux patients non irradies. Conclusion Ces elements doivent etre integres dans le suivi a long terme des enfants ayant eu un cancer pour une meilleure prevention et/ou un traitement precoce de ces complications.

A Federated Learning approach consists of creating an AI model from multiple data sources, without moving large amounts of data across to a central environment. Federated learning can be very useful in a tactical coalition environment, where data can be collected individually by each of the coalition partners, but network connectivity is inadequate to move the data to a central environment. However, such data collected is often dirty and imperfect. The data can be imbalanced, and in some cases, some classes can be completely missing from some coalition partners. Under these conditions, traditional approaches for federated learning can result in models that are highly inaccurate. In this paper, we propose approaches that can result in good machine learning models even in the environments where the data may be highly skewed, and study their performance under different environments.

The vertical distribution of PCBs was measured in a dated core from the continental shelf of the Korea Strait. The historical trend of deposition and fluxes of individual and total PCB agreed well with the dynamics of historical tendencies of PCBs consumption in South Korea up to mid-1980 and a peak of total PCBs of 810 ng kg−1 was recorded at the turn of the 1960s. A second period of deposition, when concentrations of total PCB up to 1007 ng kg−1 were reached, was evidenced between 1989 and 2010 after the ban of PCBs. Sediments deposited in 1990s–2010, and sediments deposited in the period of maximum PCBs use (1956–1983) are both enriched in the less chlorinated homologue groups (tri- and tetrachlorobyphenyls) and congener PCB 118. However, the ratio of dioxin-like PCBs, and dichloro- and hexachloro homologue groups disclosed compositional variations between the two time periods. Source analysis suggested that PCBs in the sediment record mainly originated from Kanechlor 300, Kanechlor 400 and Aroclor 1242 technical mixtures overlapped by secondary/unintentional combustion sources from regional steel making processes in the last decades (1990s-2010).

Network topology plays an important role in many network operations. However, it is very difficult to obtain the topology of public networks due to the lack of internal cooperation. Network tomography provides a powerful solution that can infer the network routing topology from end-to-end measurements. Existing solutions all assume that routes from a single source form a tree. However, with the rapid deployment of Software Defined Networking (SDN) and Network Function Virtualization (NFV), the routing paths in modern networks are becoming more complex. To address this problem, we propose a novel inference problem, called the weight inference problem, which infers the finest-granularity information from end-to-end measurements on general routing paths in general topologies. Our measurements are based on emulated multicast probes with a controllable “width”. We show that the problem has a unique solution when the multicast width is unconstrained; otherwise, we show that the problem can be treated as a sparse approximation problem, which allows us to apply variations of the pursuit algorithms. Simulations based on real network topologies show that our solution significantly outperforms a state-of-the-art network tomography algorithm, and increasing the width of multicast substantially improves the inference accuracy.

Mobile edge computing (MEC) is a promising technique for providing low-latency access to services at the network edge. The services are hosted at various types of edge nodes with both computation and communication capabilities. Due to the heterogeneity of edge node characteristics and user locations, the performance of MEC varies depending on where the service is hosted. In this paper, we consider such a heterogeneous MEC system, and focus on the problem of placing multiple services in the system to maximize the total reward. We show that the problem is NP-hard via reduction from the set cover problem, and propose a deterministic approximation algorithm to solve the problem, which has an approximation ratio that is not worse than $\left(1-e^{-1}\right)/4$. The proposed algorithm is based on two sub-routines that are suitable for small and arbitrarily sized services, respectively. The algorithm is designed using a novel way of partitioning each edge node into multiple slots, where each slot contains one service. The approximation guarantee is obtained via a specialization of the method of conditional expectations, which uses a randomized procedure as an intermediate step. In addition to theoretical guarantees, simulation results also show that the proposed algorithm outperforms other state-of-the-art approaches., Comment: Extended version of paper presented at IEEE INFOCOM 2019

The Life Cycle Assessment (LCA) methodology is widely applied in several industrial sectors to evaluate the environmental performance of processes, products and services. Recently, several reports and studies have emphasized the importance of LCA in the field of engineered nanomaterials. However, to date only a few LCA studies on nanotechnology have been carried out, and fewer still have assessed aspects relating to ecotoxicity. This is mainly due to the lack of knowledge in relation on human and environmental exposure and effect of engineered nanoparticles (ENPs). This bottleneck is continued when performing Life Cycle Impact Assessment, where characterization models and consequently characterization factors (CFs) for ENPs are missing. This paper aims to provide the freshwater ecotoxicity CF for titanium dioxide nanoparticles (nano-TiO2). The USEtox™ model has been selected as a characterisation model. An adjusted multimedia fate model has been developed which accounts for nano-specific fate process descriptors (i.e. sedimentation, aggregation with suspended particle matter, etc.) to estimate the fate of nano-TiO2 in freshwater. A literature survey of toxicity tests performed on freshwater organism representative of multiple trophic levels was conducted, including algae, crustaceans and fish in order to collect relevant EC50 values. Then, the toxic effect of nano-TiO2 was computed on the basis of the HC50 value. Thus, following the principle of USEtox™ model and accounting for nano-specific descriptors a CF for the toxic impact of freshwater ecotoxicity of 0.28 PAF day m3 kg− 1 is proposed.

Fatty acid amide hydrolase (FAAH) is a membrane anchored serine hydrolase that has a principle role in the metabolism of the endogenous cannabinoid anandamide. Docking studies using representative FAAH crystal structures revealed that compounds containing a novel piperidinyl thiazole isoxazoline core fit within the ligand binding domains. New potential FAAH inhibitors were designed and synthesized incorporating urea, carbamate, alkyldione and thiourea reactive centers as potential pharmacophores. A small library of candidate compounds (75) was then screened against human FAAH leading to the identification of new carbamate and urea based inhibitors ( K i = pM and nM, respectively). Representative carbamate and urea based chemotypes displayed slow, time dependent inhibition kinetics leading to enzyme inactivation which was slowly reversible. However, evidence indicated that features of the mechanism of inactivation differ between the two pharmacophore types. Selected compounds were also evaluated for analgesic activity in the mouse-tail flick test.

The effect of the administration of beneficial lactic acid bacteria (LAB): Lactococcus lactis CRL 1584, L. lactis CRL 1827, Enterococcus gallinarum CRL 1826 and combined CRL 1584+ CRL 1826 on the development of bullfrog embryos from the hatching stage until 31 days (tadpole) was evaluated. In vitro assays indicated that 103, 106 and 109 CFU mL−1 single LAB strains remained viable until 24 h in 10% Ringer. Around 109 CFU mL−1 LAB (individually and combined) were used in an experimental design built to evaluate their effect when administrated at different intervals (three 7-day cycles with 5-day rest periods in between) to embryos until day 31. The highest potentially beneficial population (LAB) numbers were detected in the LAB-treated groups. All the LAB-treatments increased it and were significantly higher than the controls. Although the highest, potentially pathogenic, population (Red-Leg Syndrome-RLS-related pathogens) numbers were detected in the control and the lowest in the CRL 1584+ CRL 1826-treated group, they did not differ significantly. Stereoscopic studies showed no malformations in any LAB-treated group and all the specimens reached the same stage of their biological cycle with a survival >94%. The histological structure of target organs for RLS-associated pathogens (intestine and skin) and stomach was not affected and the spleen was developed. Only the LAB-treated groups showed microorganisms associated with the intestinal mucus, without inflammatory reaction in the lamina propria. This is the first report on the evaluation of the absence of adverse effects after LAB administration to bullfrog embryos using indigenous microorganisms. Fil: Pasteris, Sergio Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina Fil: Montel Mendoza, María Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina Fil: Llanos, Ricardo J.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina Fil: Pucci Alcaide, Franco J.. Fundación Miguel Lillo; Argentina Fil: Nader, Maria Elena Fatima. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentina

Phosphate is commonly added to drinking water to inhibit lead release from lead service lines and lead-containing materials in premise plumbing. Phosphate addition promotes the formation of lead phosphate particles, and their aggregation behaviors may affect their transport in pipes. Here, lead phosphate formation and aggregation were studied under varied aqueous conditions typical of water supply systems. Under high aqueous PO4/Pb molar ratios (>1), phosphate adsorption made the particles more negatively charged. Therefore, enhanced stability of lead phosphate particles was observed, suggesting that although addition of excess phosphate can lower the dissolved lead concentrations in tap water, it may increase concentrations of particulate lead. Adsorption of divalent cations (Ca2+ and Mg2+) onto lead phosphate particles neutralized their negative surface charges and promoted their aggregation at pH 7, indicating that phosphate addition for lead immobilization may be more efficient in harder waters. The p...

In this paper, we discuss the problem of distributed learning for coalition operations. We consider a scenario where different coalition forces are running learning systems independently but want to merge the insights obtained from all the learning systems to share knowledge and use a single model combining all of their individual models. We consider the challenges involved in such fusion of models, and propose an algorithm that can find the right fused model in an efficient manner.

To present a retrospective study of nine children with Panayiotopoulos syndrome associated with diffuse spikes and waves as the sole EEG manifestation at onset. Charts of children with typical clinical criteria of Panayiotopoulos syndrome, electroclinically followed between February 2000 and February 2012, were reviewed. Among 150 patients who met the electroclinical criteria of Panayiotopoulos syndrome, we identified nine children who presented with the typical clinical manifestations but who, on EEG, only had diffuse paroxysms at onset that continued along the course of the syndrome. In three, in addition to the diffuse paroxysms, focal spikes appeared later. From a clinical point of view, other features were otherwise unremarkable. Diffuse spike-and-wave discharges were observed in all patients when awake and during sleep (100%). Later, three children also had focal spikes during sleep, which were occipital in one, frontal in one, and temporo-occipital in the remaining patient. Spikes were activated by sleep in all three cases. During disease evolution, no particular electroclinical pattern was observed. Two patients who received clobazam and carbamazepine, respectively, did not respond well to the drugs and valproic acid was added with excellent seizure control. Outcome was good. We present evidence that patients with Panayiotopoulos syndrome may have diffuse discharges at onset as the sole EEG manifestation, which last throughout the course of the syndrome. In some, focal paroxysms developed later. The course was benign. In our group of patients, clinical features and evolution were similar to those of typical cases of Panayiotopoulos syndrome.

Apatite has numerous applications that benefit society. The atomic arrangement of the apatite crystal structure and its rich and variable chemistry impart unique properties, which permit a wide range of technological and scientific applications in an array of disciplines outside of the traditional Earth sciences, including ecology, agronomy, biology, medicine, archeology, environmental remediation, and materials science. In our daily lives, apatite is essential for sustaining and enhancing human life through agricultural amendments, through bone replacements, through fluorescent lights, and through environmental remediation of contaminated soils. Apatite is truly a technological gem.

Carbonated strontium fluor-, hydroxyl- and chlorapatites (carbonated Sr10(PO4)6X2 = CSrApX, where X= OH, Cl and F) were synthesized in aqueous solution. The substitution mode of carbonate was determined from infrared (IR) stretching frequencies for carbonate and from the variation in unit-cell axial lengths as a function of carbonate content. The a-axis lengths of CSrApF and CSrApCl decrease, whereas the a-axis length of CSrApOH increases slightly with increasing carbonate substitution. The carbonate IR stretching region from ∼1390 to 1590 cm–1 contains two doublets for both CSrApOH and CSrApCl, indicating the presence of both A- and B-type carbonate. The carbonate spectral region for CSrApF is reminiscent of that for CCaApF, which contains one doublet for B-type carbonate with a small shoulder attributable to A-type carbonate. Activity-based Ksp values (assuming B-type substitution) were determined for all three series of carbonated Sr apatites and show that the solubilities of CSrApOH and CSrApCl increase at higher carbonate values, whereas those of CSrApF stay constant. The Ksp values for uncarbonated SrApOH, SrApCl and SrApF were determined by extrapolation to zero percent carbonate (10–120, 10–112 and 10–113 for SrApOH, SrApCl and SrApF, respectively).

Key trace minerals greatly strengthen teeth The outer layers of teeth are made up of nanowires of enamel that are prone to decay. Gordon et al. analyzed the composition of tooth enamel from a variety of rodents at the nanometer scale (see the Perspective by Politi). In regular and pigmented enamel, which contain different trace elements at varying boundary regions, two intergranular phases—magnesium amorphous calcium phosphate or a mixed-phase iron oxide—control the rates of enamel demineralization. This suggests that there may be alternative options to fluoridation for strengthening teeth against decay. Science , this issue p. 746 ; see also p. 712

Purpose To retrospectively analyze the electroclinical characteristics, etiology, treatment, and prognosis of patients with epileptic encephalopathy with status epilepticus during sleep (ESES) with unusual EEG features and to corroborate if this series of patients is part of the ESES syndrome. Method Charts of 17 patients with typical clinical manifestations of the ESES syndrome with focal ESES of non-REM sleep at onset and during the focal ESES phase, or bilateral synchronic and asynchronic ESES with a symmetric or asymmetric morphology, continuous or subcontinuous and sometimes multifocal paroxysms with or without slow-wave activity during slow sleep seen between 2000 and 2012 were analyzed. Results Mean patient follow-up from onset was 7.5 years. An idiopathic cause was found in seven patients, a structural cause in eight, and etiology was unknown in the remaining two. The median age at onset of the unusual ESES syndrome was 7 years. During the ESES phase, 15 children developed new seizure types, negative myoclonus was observed in seven patients, positive myoclonus in five, and absences in nine. Six patients had motor impairment, two had auditory verbal agnosia, and two had motor speech impairment. Attention deficit hyperactivity disorder was observed in four, aggressiveness in six, memory deficit in two, and impaired temporospatial orientation in four. The patients with focal ESES in the frontal region showed behavioral disturbances and/or motor deterioration, and in those with temporo-occipital involvement the dominant clinical manifestations were language and/or behavioral disturbances. Conclusion Our patients with typical clinical manifestations of ESES syndrome but with unusual EEG patterns may be variants of this syndrome.

Volcanic eruptions contribute to climate variability, but quantifying these contributions has been limited by inconsistencies in the timing of atmospheric volcanic aerosol loading determined from ice cores and subsequent cooling from climate proxies such as tree rings. Here we resolve these inconsistencies and show that large eruptions in the tropics and high latitudes were primary drivers of interannual-to-decadal temperature variability in the Northern Hemisphere during the past 2,500 years. Our results are based on new records of atmospheric aerosol loading developed from high-resolution, multi-parameter measurements from an array of Greenland and Antarctic ice cores as well as distinctive age markers to constrain chronologies. Overall, cooling was proportional to the magnitude of volcanic forcing and persisted for up to ten years after some of the largest eruptive episodes. Our revised timescale more firmly implicates volcanic eruptions as catalysts in the major sixth-century pandemics, famines, and socioeconomic disruptions in Eurasia and Mesoamerica while allowing multi-millennium quantification of climate response to volcanic forcing.

Confirmation of structural H2O in apatites using 2H solid state NMR spectroscopy has been followed by the determination of the number of molecules of H2O per unit cell (MPUC) using thermal gravimetric analysis (TGA) in 10 series of carbonated apatites [CMApX; M10(PO4)6X2 = MApX] containing the divalent cations (M) calcium, strontium, barium, and lead, and monovalent anions (X) OH−, F−, and Cl−. For many of the series, the average MPUC ranges from ca. 1.5–2.5 and is independent of the concentration (wt%) of carbonate. For other series, the average MPUC is as low as ca. 0.8 or as high as ca. 4.0. We have found for six of the series, i.e., those in which carbonate predominantly (>90%) substitutes for phosphate that the average MPUC correlates with cation and anion atomic radii, with unit-cell axial lengths, and, especially, with our calculations of the void space available in the c -axis channels. We speculate that the volume of the channels in apatites affects the ability of H2O to occupy channel sites. In most low-temperature apatites of the type M10(PO4)6X2 that have been studied, carbonate prefers to substitute for phosphate (B-type substitution) rather than for monovalent anions in channel sites (A-type substitution), although computer simulations indicate that carbonate is more thermodynamically stable in the channel sites rather than the phosphate sites. In apatites with nearly total B-type carbonate substitution, there is no relationship between the number of molecules of H2O in the channels and the weight percent carbonate in the apatite. This lack of correlation would be expected when there is no competition within the channel between H2O and carbonate occupancy. In apatites with greater channel volumes, however, we infer that increased ease of carbonate incorporation in the channels also increases competition between H2O and carbonate. The originally incorporated amount of H2O is diminished to accommodate the thermodynamically favored carbonate ion substitution in the channels. We further speculate that these scenarios are most easily rationalized by incorporation of H2O early in the formation of nascent crystallites of apatites formed in aqueous solution, with carbonate entering the newly formed channels later and, in some cases, with difficulty.

The European Water Framework Directive (WFD) establishes a framework for the protection and improvement of all water bodies including transitional waters; its final objective is to achieve at least 'good status' by 2015. In the present work, a hierarchical sampling design was applied to analyze the influence of anthropogenic inputs on the spatial distribution of metals, polychlorinated dibenzo-p-dioxins (PCDDs) dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in sediment at four areas in Pialassa Baiona coastal lagoon. In order to assess the chemical status, levels of priority substances and other pollutants were compared with the recently developed national Environmental Quality Standards (EQS) and site specific background levels for metals. Levels of mercury and PCBs were particularly high and exceeded their national EQS values at all sampled areas, thus not contributing to the achievement of a good chemical status of this transitional water body according to the WFD classification.

Since the 1990s red-tide blooms of Fibrocapsa japonica have frequently been observed in European waters; despite their recurrence also in the Adriatic coastal areas, they have never been conclusively linked to ichthyotoxic events. Since the toxicity of F. japonica is still under debate and its effects differ among the strains, in this study all the compounds previously postulated as involved in the toxic mechanism, such as brevetoxins, fatty acids and ROS, were screened for Adriatic strains. Whole algal extracts were analyzed for brevetoxin PbTx-2, which was not found, and for a qualitative and quantitative analysis of fatty acids. The fatty acid profile evidenced the presence of PUFAs, with considerable amounts of 18:4n-3, 20:4n-6, and 20:5n-3, as already found in different strains, but with a lower amount of arachidonic acid (20:4n-6). None of the PUFAs was released in the extracellular medium. Different toxicological assays (Vibrio fischeri, Artemia sp., haemolysis of fish erythrocytes) were performed using algal cellular, extracellular or subcellular samples as well as fractions of the algal extract, in order to identify the toxic compounds. The tested cultures were found to inhibit V. fischeri bioluminescence, to affect Artemia nauplii viability and to have haemolytic effects comparable to those previously observed in different strains. The solid phase extraction (SPE) of the Adriatic F. japonica extracts resulted in a high concentration of PUFAs in two main fractions, which caused mortality in Artemia nauplii and inhibition of V. fischeri bioluminescence. Fish (Dicentrarchus labrax) assays were also performed, reporting mortality after long exposure times and the cause of fish death was investigated. A significant increase of H2O2 in the tanks where sea basses were exposed to F. japonica was obtained, indicating that the presence of fish stimulates H2O2 production by algal cells and leading to the hypothesis of H2O2 involvement in F. japonica toxicity. The presence of oxidative stress in the exposed fish was confirmed by the increased malondialdehyde concentration in their gills. Overall these results indicate that since F. japonica cells can easily cling to fish gills, due to their high polysaccharide production, it is presumable that high PUFA amounts are released in loco, as a result of cell breakage, and that exert their toxicity together with ROS. This study shows that the Adriatic strains of F. japonica can be harmful to higher level organisms. Nevertheless a high cell density and a long lasting bloom are necessary to cause severe damage to fish gills or death for crustaceans.

A seven-well drilling campaign was carried out in Malaysia brown field targeted for enhanced oil recovery (EOR) purpose. The targeted sands were heavily depleted with pore pressure as low as 4 ppg. Good hydraulic isolation in the annulus is critical to prevent the production of unwanted fluid, i.e. water behind casing. The cement evaluation logs performed in the first four wells revealed presence of microannulus response across the same sands in the field. This microannulus occurrence complicated the decision making on perforation intervals. There was a need to prevent or to minimize the microannulus occurrence in the subsequent three wells that planned to penetrate the same sands. A systematic approach had to be taken to integrate the multiple-domains raw datas and a platform was needed to analyze the data to resolve the problems. Integrated workflow was introduced for the first time in South East Asia region. Via integrated workflow, a thorough study integrating the data from multiple domains i.e. drilling data, well trajectory, petrophysical evaluation, pore pressure, cementing design and execution, effective mud removal, centralizers’ performance evaluation and cement evaluation logs, was performed on the first four wells, with the key objective to identify the root cause for the microannulus response. The root cause for the microannulus in these four wells was successfully identified, besides verifying the centralizers’ performance and mud rheology in slurry displacement process. The solution was able to be proposed and implemented in the subsequent three wells’ cementing recipe, which include the usage of lightweight cement, fluid loss optimization and formation netting using fiber. The efficiency of the proposed enhancement on the cementing recipe was verified through the obvious improvement in the cement evaluation logs in the wells that followed the integrated platform recommendations. The microannulus impact was greatly reduced in these wells which penetrated the same problematic sands as in first four wells. The hydraulic isolation evaluation in the planned perforations could be performed with less ambiguity and the confidence on the cement quality for long term well integrity assurance increased. This improvement further verified the key reason identified for the microannulus occurrence. Integrated workflow could increase the level of assurance on cement evaluation by integrating the data via robust workflow and access to the experts in multiple disciplines. The platform provided valuable information by correlating open-hole formation evaluation logs, surface measurements and cementing data using acoustic logs. A complete database was established for cementing planning in future EOR wells. The production data from these newly completed wells complement the study and confirm the efficiency of hydraulic isolation. This workflow has served as maiden approach to develop the cement evaluation integrated platform in South East Asia region.

Two probable causes of variability in the Raman spectrum of unpolished pyrite are well recognized, in principle, but not always in practice, namely: (1) downshifting of band positions due to laser heating; and (2) variations in the ratios of band intensities due to crystallographic orientation of the sample with respect to the laser’s dominant polarization plane. The aims of this paper are to determine whether these variations can be used to acquire additional information about pyrites. Here, using laser Raman microprobe analysis of natural, unpolished pyrite samples, we investigate the magnitude of downshifting of band positions associated with laser heating of different sizes of pyrite grains. We demonstrate that the magnitude of this effect can be large (up to ∼10 cm−1), negatively proportional to grain size, of greater magnitude than the effect typically attributable to natural intersample differences in trace element (TE) solid solution, and of similar magnitude among bands. Through Raman analysis of naturally occurring faces on pyrite samples at various angles of rotation, we also demonstrate that the three most common faces on pyrite can be distinguished by the ratio of the intensities of the dominant bands. We conclude that for unpolished samples, laser Raman microprobe analysis is most effective as a means of identifying pyrite, and the presence of solid solution therein, when laser power is low enough to avoid substantial heating. Once pyrite has been identified, higher laser powers can be used to produce spectra whose ratios of band intensities indicate the face or crystallographic plane being irradiated.

We consider a distributed edge computing system where we have a number of interconnected machines with limited communication bandwidth and storage capacity. Analytics tasks run on the machines, where each task runs on a single machine but may require data from multiple other machines. Every task requires a given amount of data to run, and it needs to receive all its data within a specific deadline. The application scenario is that each machine has limited storage, thus we usually cannot place the entire amount of data for a specific task on a single machine that executes the task. We assume that the task execution is sparse in time, so that at most one task is executed in the system at any time. The problem we study in this paper is how to distribute the data on machines in the system, without violating the bandwidth and storage constraints, while ensuring that the data transfer deadlines are met. We prove that the optimal solution to this problem is equivalent to that of a max-flow problem on a specifically constructed graph. We present how to construct this graph so that the problem can be solved using standard algorithms for max-flow problems, and also provide some numerical results and further discussions.

Escherichia coli is a natural colonizer of the urogenital mucosa of healthy females; however it is one of the pathogens associated to reproductive failures in cows and sows. A better knowledge about the characteristics of native E. coli will allow us to differentiate them from pathogenic strains. Ninety autochthonous isolates from the reproductive tract of sows and cows were characterized to determine the phylogenetic profile, antibiotic resistance and virulence factors; also, comparisons between different breeding systems were performed. Vaginal colonization of E. coli was statistically higher in cows (57.5%) than sows (23.8%), and most isolates belonged to the phylogenetic group A: 79.69 and 80.77%, respectively; moreover phylo-groups B1 (12.5 and 11.54%) and D (7.81 and 7.69%) were significantly lower; however, none was classified as B2. Positive associations between virulence factors and group D were found. Isolates with antimicrobial susceptibility were associated with group A and the MDR (Multiple Drug Resistance) was related to the porcine source. These results contribute to the knowledge of extra-intestinal E. coli populations; which could affect the reproductive performance of females. Fil: Torres Luque, Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina Fil: Gonzalez Moreno, Candelaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; Argentina Fil: Pasteris, Sergio Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina Fil: Orden, José A.. Universidad Complutense de Madrid; España Fil: Leon de la Fuente, Ricardo Alfonso. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Complutense de Madrid; España Fil: Otero, María Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina

A flowing or pressure-sustained annulus is a live threat to the environment, population, vegetation, and natural habitat. In the current oilfield environment under strengthened regulations from regulatory authorities, zonal isolation must be assured before completely abandoning a well. In the west region of Sumatra, Indonesia, a large number of shallow injector wells are drilled; after passing a certain age and productive life, they are abandoned. Most of these wells have lost circulation and therefore need a cost- and time-efficient cement placement method that can demonstrate zonal isolation by means of cement bond logs. The conventional cement placement method across the perforations requires several steps: placing cement, squeezing, leaving the cement on top of the perforations, waiting on cement, drilling the cement, and running the cement bond log. A novel squeeze method was deployed as a solution by combining a chemical contaminant and a squeeze technique. The objective was to perform the cement bond log directly after wait on cement without spending time to drill out the cement. In this technique, cement was placed using a coiled tubing pump-and-pull method: A squeeze was performed in the perforations; then coiled tubing was run into the well below 30 ft of perforations and an engineered contaminant fluid was pumped to contaminate the cement in the tubing. After the recommended wait- on-cement time, the cement bond log was run to confirm zonal isolation across the perforations. This technique eliminated the need to drill the set cement in the slim tubing, saving several days of work time. In most of the wells, the cement bond log showed less than 5 mV, which helped to determine the achievement of zonal isolation. Furthermore pressure tests were conducted to ensure the zonal isolation across the perforated intervals. Engineered cement and contaminant design is required to ensure cement will gain and maintain designed mechanical properties behind the tubing. This paper will discuss the case histories from six wells in the west region of Sumatra field, where the novel coiled tubing placement technique has been applied and proven successful and cost-effective.