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Campylobacter genus encompasses many species, among which C. jejuni, C. coli and C. fetus are the main human pathogens. C. jejuni/coli frequently cause self-limited enteritis in immunocompetent hosts and are seldomly associated with bacteriemia. C. fetus is less common as a human pathogen. It is rarely identified in fecal samples but can sometimes be isolated in blood samples from patients with comorbidities or immunosuppression. Campylobacter fetus bacteriemia is remarkable since it is associated with endovascular and deep-seated infections.

Ultrasound-assisted extraction (UAE) methods for food analysis are recognized as being in accordance with the principles of green analytical chemistry (GAC). Reference standard methods generally use microwave-assisted extraction (MAE) for sample digestion; however, the use of ultrasonication processes has many advantages. Herein, a simple, and economical method for the determination of Cd and Pb in fruits and vegetables for food safety monitoring is reported. This method was optimized using a standard reference material (SRM, spinach leaves) through a multivariate experimental design (optimal conditions: 0.5 g of sample, 15 min of sonication, and 20.00 mL of 2.5 mol L−1 HNO3) and subsequently validated. The limits of detection obtained were one or two orders of magnitude lower than those achieved with MAE, making this a promising technique for contaminants monitoring. The UAE method was then tested on vegetable samples (apples, carrots, tomatoes, and lettuce) obtained from commercial sources in Uruguay and a comparison was made with samples treated by MAE. Both processes yielded comparable results, and the levels of Cd and Pb in all samples were below the maximum allowed concentration (MAC) established by the World Health Organization (WHO). In addition, to provide insight into the mechanism by which the ultrasonic process aids extraction, confocal optical images of the surface of the SRM were obtained. The leaves were examined after treatment at different sonication times (5?20 min). The confocal microscopy images show the effects of the ultrasonic treatment on the plant tissue, including desaturation, erosion, and abrasion, which increased with increasing sonication time. In conclusion, the UAE method meets and overcome the requirements of a standard method for food safety assurance.

Calcium aluminum rich inclusions (CAIs) are one of the first solids to have condensed in the solar nebula, while presolar grains formed in various evolved stellar environments. It is generally accepted that CAIs formed close to the Sun at temperatures above 1500 K, where presolar grains could not survive, and were then transported to other regions of the nebula where the accretion of planetesimals took place. In this context, a commonly held view is that presolar grains are found solely in the fine-grained rims surrounding chondrules and in the low-temperature fine-grained matrix that binds the various meteoritic components together. Here we demonstrate, based on noble gas isotopic signatures, that presolar SiC have been incorporated into fine-grained CAIs in the Allende carbonaceous chondrite at the time of their formation, and have survived parent body processing. This finding provides new clues on the conditions in the nascent solar system at the condensation of first solids., Comment: 4 figures

RESUMEN.Las frutas y hortalizas pueden contener contaminantes que llegan al producto en cualquier punto de la cadena productiva. En este sentido, se debe controlar la acumulación de elementos potencialmente tóxicos como arsénico (As), cadmio (Cd) y plomo (Pb) para asegurar y controlar la inocuidad de estos alimentos.Con el objetivo de monitorear los contaminantes inorgánicos, de forma rápida, confiable y con métodos analíticos en acuerdo con los principios de la química ­verde, se desarrolló y validó una metodología para la extracción simultánea de estos elementos asistida con microondas, en un solo paso y utilizando ácido diluido.Se aplicó el método validado a cuatro productos: zanahoria, lechuga, manzana y tomate. Los parámetros de desempeño de esta metodología indicaron que resultó adecuada para monitorear estos alimentos tomando como referencia la reglamentación vigente y que todas las muestras analizadas cumplieron con los criterios establecidos. Esta metodología validada puede ser considerada como alternativa a los métodos estándar de análisis de As, Cd y Pb en este tipo de alimentos. El desarrollo de estas herramientas analíticas es de relevancia y deja disponible una plataforma analítica al servicio del sector productivo y de organismos de contralor nacional.ABSTRACT.Fruits and vegetables may contain contaminants that reach the product at any point in the production chain. In this sense, the accumulation of potentially toxic elements such as arsenic (As), cadmium (Cd) and lead (Pb) must be controlled to ensure food safety.In order to monitor inorganic pollutants, a fast and reliable analytical method also following the principles of green chemistry was developed and validated for simultaneous extraction of these elements using a microwave-assisted procedure, in a single step and with diluted acid. The validated method was applied in four products: carrot, lettuce, apple and tomato. The figures of merit of this methodology indicated that it was adequate to monitor these contaminants in the analyzed foods fulfilling with the current regulations. The developed method can be considered as an alternative to standard methods for the determination of As, Cd and Pb in these foods. These kinds of studies applied to monitor food safety are relevant and, in this case, an analytical platform is now available for the productive sector and national control agencies.

The timing and magnitude of the oxygenation of Earth’s ocean is still a matter of intense debate. Previous work suggested that the uranium isotope variations recorded in ancient marine sediments, such as shales and carbonates, could provide valuable insights into paleoredox conditions [e.g., 1-11]. In this work, we study U concentration and isotopic composition of a large number of Precambrian carbonates to place constraints on long-term variations in oceanic redox conditions.

The Allende fine-grained inclusion Curious Marie is a unique CAI. It is depleted in uranium but contains large ^(235)U excess [1], providing new evidence that ^(247)Cm was alive in the Early Solar System, as has been previously suggested [2], and leading to an updated (^(247)Cm/^(235)U)initial ratio of (1.1±0.3)×10^(-4).

Lanthanides are a group of 14 naturally occurring elements with atomic numbers ranging from 57 (La) to 74 (Lu), which are also known as rare earth elements (REE). REEs are ubiquitous in minerals and rocks. The chemical properties of REEs vary as smooth functions of their atomic numbers, a phenomenon known as the contraction of the lanthanides. This is the main control behind REE fractionation in minerals and rocks. The relative abundance of REEs is usually presented as the REE pattern by normalizing the concentrations in the sample to those in reference materials such as chondrites and shales.

Angrites are a series of differentiat-ed meteorites, extremely silica undersaturated and with unusally high Ca and Al contents [1]. They are thought to originate from a small planetesimal parent body of ~ 100-200 km in radius ([2-3]), can be either plutonic (i.e., cumulates) or volcanic (often referred to as quenched) in origin, and their old formation ages (4 to 11 Myr after CAIs) have made them prime anchors to tie the relative chronologies inferred from short-lived radionuclides (e.g., Al-Mg, Mn-Cr, Hf-W) to the absolute Pb-Pb clock [4]. They are also the most vola-tile element-depleted meteorites available, displaying a K-depletion of a factor of 110 relative to CIs.

Isotopic anomalies are departures from the laws of mass-dependent fractionation that cannot be explained by radioactive decay, cosmogenic effects, or exotic isotopic fractionation processes such as nuclear field shift or magnetic effects [1 and references therein]. These anomalies often have a nucleosynthetic origin and provide clues on the stellar origin and solar system processing of presolar dust. Anomalies are most often found in refractory elements of relatively low mass, so Sr is a prime target for study. The four stable isotopes of strontium are useful for discerning the various nucleosynthetic origins of early solar system building blocks and the timing of accretion processes. Strontium-84 is the least abundant (0.56%) of these isotopes, but is particularly significant in being a p-process only nuclide that is produced in core-collapse or type Ia supernovae [2,3]. The more abundant isotopes ^(86)Sr (9.86%), ^(87)Sr (7.00%) and ^(88)Sr (82.58%) are produced in s- and r-processes in asymptotic giant branch stars and other stellar types [4]. Additionally, ^(87)Sr is produced by ^(87)Rb decay in proportions that dominate over possible nucleosynthetic variations but provide timings of early solar system processes, most notably volatile element depletion [5-7]. Furthermore, variations in strontium isotopic ratios caused by high-temperature massdependent fractionation [8] are also important [9-12], as they provide insights into nebular and accretionary processes.

The European Conference on Infections in Leukemia (ECIL) provides recommendations for diagnostic strategies and prophylactic, pre-emptive or targeted therapy strategies for various types of infection in patients with hematologic malignancies or hematopoietic stem cell transplantation recipients. Meetings are held every two years since 2005 and evidence-based recommendations are elaborated after evaluation of the literature and discussion among specialists of nearly all European countries. In this manuscript, the ECIL group presents the 2015-update of the recommendations for the targeted treatment of invasive candidiasis, aspergillosis and mucormycosis. Current data now allow a very strong recommendation in favor of echinocandins for first-line therapy of candidemia irrespective of the underlying predisposing factors. Anidulafungin has been given the same grading as the other echinocandins for hemato-oncological patients. The beneficial role of catheter removal in candidemia is strengthened. Aspergillus guidelines now recommend the use of either voriconazole or isavuconazole for first-line treatment of invasive aspergillosis, while first-line combination antifungal therapy is not routinely recommended. As only few new data were published since the last ECIL guidelines, no major changes were made to mucormycosis recommendations.

Mass-dependent fractionations (MDFs) of stable isotopes record critical information regarding the origin and evolution of planetary materials [1]. Studies of MDF of refractory lithophile elements (RLEs) can provide insights into condensation/evaporation and planetary accretion processes in the early solar system. For example, the lighter calcium isotope composition observed in carbonaceous meteorites compared to that of the bulk silicate Earth, enstatite and ordinary chondrites [2, 3] may be due to the contribution of refractory dust [4, 5], which has a light Ca isotope composition [6, 7]. In contrast, titanium, another RLE with a similar chemical behavior in the early solar system, was found to have uniform isotope compositions among different groups of meteorites including carbonaceous chondrites [8]. A potential explanation for the dichotomy of these two refractory elements could be connected to the higher 50% condensation temperature of Ti relative to Ca [9]. The isotopic results suggest that no Ti net loss took place from the CAI-forming region, while not all Ca condensed in the CAIs [7, 8]. Clearly, more proxies are needed to better understand the processes that occurred during the condensation of the solar nebula.

The European Conference on Infections in Leukemia (ECIL) provides recommendations for diagnostic strategies and prophylactic, pre-emptive or targeted therapy strategies for various types of infection in patients with hematologic malignancies or hematopoietic stem cell transplantation recipients. Meetings are held every two years since 2005 and evidence-based recommendations are elaborated after evaluation of the literature and discussion among specialists of nearly all European countries. In this manuscript, the ECIL group presents the 2015-update of the recommendations for the targeted treatment of invasive candidiasis, aspergillosis and mucormycosis. Current data now allow a very strong recommendation in favor of echinocandins for first-line therapy of candidemia irrespective of the underlying predisposing factors. Anidulafungin has been given the same grading as the other echinocandins for hemato-oncological patients. The beneficial role of catheter removal in candidemia is strengthened. Aspergillus guidelines now recommend the use of either voriconazole or isavuconazole for first-line treatment of invasive aspergillosis, while first-line combination antifungal therapy is not routinely recommended. As only few new data were published since the last ECIL guidelines, no major changes were made to mucormycosis recommendations. © 2017 Ferrata Storti Foundation.

The initiation of systemic antimicrobial treatment of Pneumocystis jirovecii pneumonia (PCP) is triggered by clinical signs and symptoms, typical radiological and occasionally laboratory findings in patients at risk of this infection. Diagnostic proof by bronchoalveolar lavage should not delay the start of treatment. Most patients with haematological malignancies present with a severe PCP; therefore, antimicrobial therapy should be started intravenously. High-dose trimethoprim/sulfamethoxazole is the treatment of choice. In patients with documented intolerance to this regimen, the preferred alternative is the combination of primaquine plus clindamycin. Treatment success should be first evaluated after 1 week, and in case of clinical non-response, pulmonary CT scan and bronchoalveolar lavage should be repeated to look for secondary or co-infections. Treatment duration typically is 3 weeks and secondary anti-PCP prophylaxis is indicated in all patients thereafter. In patients with critical respiratory failure, non-invasive ventilation is not significantly superior to intubation and mechanical ventilation. The administration of glucocorticoids must be decided on a case-by-case basis.

The Early Solar System (ESS) abundance of short-lived radionuclides (SLR) can be interpreted in terms of a free-decay interval (Δ) or a mixing timescale (τ), which correspond to complete or partial isolation from fresh nucleosynthetic inputs of the molecular could core parental to the solar system. For r-nuclides, however, the abundances measured in ESS materials require less isolation for ^(107)Pd and ^(182)Hf (Δ~ 5 Myr) than for ^(129)I (Δ=100±7 Myr) and ^(244)Pu (Δ=158±85 Myr) [1]. To make sense of these observations, models have proposed the existence of up to three different r-processes producing, respectively, the light r-nuclides, the heavy r-nuclides and the actinides [1-4]. In this work [5], we determined the ESS abundance of another short-lived r-nuclide, the long sought after ^(247)Cm [e.g., 6-7], and show how this additional constraint is consistent with either three different r-processes, or, and more likely, a single stellar environment of r-process nucleosynthesis and a partial s-process origin for ^(107)Pd and ^(182)Hf.

Chlorine-36 (t_(1/2)=0.3 Myr) decays to either ^(36)Ar (98%, β-) or ^(36)S (1.9%, ε and β+). This radionuclide can be produced either by local irradiation of gas and/or dust of solar composition [1-2] or by stellar nucleosynthesis in AGB stars or Type II supernovae [3]. Evidence for the presence of 36Cl in the early Solar System (ESS) comes from radiogenic excesses of ^(36)Ar [4] and/or ^(36)S [5-9] in secondary phases (e.g., sodalite and wadalite) in ESS materials such as Calcium, Aluminum-rich inclusions (CAIs) and chondrules. Though the presence of ^(36)Cl in the ESS has been demonstrated, the inferred initial ^(36)Cl/^(35)Cl ratios vary a lot (from 1.0×10^(-7) to 2×10^(-5)) from one inclusion to another [5-9]. Interestingly, all secondary phases measured so far lack resolvable ^(26)Mg excesses that could be due to the decay of ^(26)Al (t_(1/2) = 0.7 Myr), implying that ^(36)Cl and ^(26)Al may not have been derived from the same source. Given that ^(26)Al could have come from a stellar source [10] and that secondary phases should have formed late, we are left with either a very high ^(36)Cl/^(35)Cl initial ratio (~ 10^(-2)) in the ESS, or a late (> 3 Myr after CAI formation) irradiation scenario for the production of ^(36)Cl [9]. ^(36)Cl/^(35)Cl ~10^(-2) far exceeds the predictions from any model (stellar nucleosynthesis or irradiation); therefore, a late irradiation scenario producing ^(36)Cl at the observed level is favored. In this framework, ^(36)Cl is produced in the early solar nebula and incorporated into CAIs via aqueous activities, which could also lead to the formation of sodalite.

Uranium has two main oxidation states: 4+ and 6+. In the modern ocean, U is present in its most oxidized, highly soluble form, U^(6+) [1]. In the Archean, however, when the oxygen concentration in the atmosphere was low, U was likely present in its reduced 4+ state, which has low solubility. This contrast in solubility behavior depending on the redox conditions makes U a very useful proxy of the global oxygenation state of the Earth. Indeed, one of the most important indicators that the pO_2 was low in the Archean is the survival of detrital uraninite [2], which is unstable under the modern oxic conditions.

Objectives Several studies have reported male-female differences in the prevalence of symptoms of work-related musculoskeletal disorders (MSD), some arising from workplace exposure differences. The objective of this paper was to compare two strategies analyzing a single dataset for the relationships between risk factors and MSD in a population-based sample with a wide range of exposures. Methods The 1998 Quebec Health and Social Survey surveyed 11 735 respondents in paid work and reported “significant” musculoskeletal pain in 11 body regions during the previous 12 months and a range of personal, physical, and psychosocial risk factors. Five studies concerning risk factors for four musculoskeletal outcomes were carried out on these data. Each included analyses with multiple logistic regression (MLR) performed separately for women, men, and the total study population. The results from these gender-stratified and unstratified analyses were compared. Results In the unstratified MLR models, gender was significantly associated with musculoskeletal pain in the neck and lower extremities, but not with low-back pain. The gender-stratified MLR models identified significant associations between each specific musculoskeletal outcome and a variety of personal characteristics and physical and psychosocial workplace exposures for each gender. Most of the associations, if present for one gender, were also found in the total population. But several risk factors present for only one gender could be detected only in a stratified analysis, whereas the unstratified analysis added little information. Conclusions Stratifying analyses by gender is necessary if a full range of associations between exposures and MSD is to be detected and understood.

CAIs are thought to be among the first solids formed in the early Solar System (ESS). As such, they are prime samples to study when (1) investigating ESS high-temperature processes, and (2) searching for evidence of short-lived radionu-clides at the time of formation of the SS. A recent systematic study of fine-grained CAIs characterized by a Group II REE pat-tern from Allende [1], found an extremely large ^(235)U excess (δ^(235)U >50 ‰ rel. to CRM-112a) in one sample: ME-3364 3.2. The discovery of this large ^(235)U excess provides definite evidence of the existence of live ^(247)Cm in the ESS, as previously suggested by [2]. In this study, we analyzed the oxygen isotope composi-tions and Al-Mg systematics of CAI ME-3364 3.2 to constrain the conditions of its formation.

Return missions are providing unique opportunities to deepen our knowledge of the formation and evolution of the solar system. The six Apollo missions have been critical in shaping our understanding of the Earth-Moon history [1], and the recent Genesis (solar wind; e.g., [2]), Stardust (cometary dust from Wild 2; e.g., [3,4]) and Hayabusa (dust from S-type asteroid from Itokawa; e.g., [5]) missions brought in a wealth of data.

The ^(235)U/^(238)U ratio shows little variability in most terrestrial and meteoritic bodies (≤1 ‰) [1-3]. In contrast, large excesses of ^(235)U, up to 3.5 ‰, have been found in a few Calcium-Aluminum rich inclusions (CAIs) and have been interpreted as evidence of live ^(247)Cm (t_(1/2) = 15.6 My) in the early solar system (SS) [4]. Though this is a plausible explanation, it relies on four points with high Nd/U ratio that define a “pseudochron”, so more work is needed to determine the cause of U isotope variations in CAIs. Here, we report some preliminary results on the identification, characterization and U isotopic analysis of 12 fine-grained, group II, CAIs from the Allende meteorite.

In the past several years, there has been a growing interest in the emerging U stable isotope systematic as it could prove a useful tracer of the redox state of the global ocean through time. However, important questions remain to be addressed before the full potential of this proxy can be exploited. In this abstract we show 1) how detrital contamination can be dealt with to avoid data misinterpretation, and 2) that bulk carbonates can record the δ^(238)U value of the seawater they form from.

With increasingly ambitious sample return missions and instrumentation of ever-increasing sensitivity and precision, column chromatography appears to be the neglected step-child of isotope geochemistry and little improvement has been brought to it in the past few decades. Traditional column chromatography (i.e., open-system, gravity driven) techniques suffer from significant limitations pertaining to the overall length of column, resin size and diffusion effects, which can severely compromise separation efficiencies. Furthermore, some fine-scale separations still require complicated multi-step, highly time-consuming protocols (e.g. Ni-Mg, [1]). High-performance liquid chromatography (HPLC), while overcoming many of these limitations (e.g. a closed-system setup; the ability to pressurize the system, hence longer columns and better separation; a semi-automated set-up), is not immune to severe drawbacks. Mainly, 1) the liquid flow path often contains glass or metal parts which are easily corroded/dissolved by concentrated acids or organic solvents, leading to contamination of the samples, and 2) the electronic controls and housing are often spatially associated with the HPLC unit, drastically shortening the lifespan of the apparatus as the metallic parts rapidly corrode in these harsh chemical environments [e.g. 2].

With the recent success of sample return missions such as Genesis (solar wind; e.g., [1-2]), Stardust (cometary dust particles; e.g., [3-5]) and Hayabusa (asteroid; e.g., [6-7]), as well as the recently announced OSIRIS-REx mission (estimated to collect more than 60 g of asteroidal material), it is clear that a new frontier of solar system research has been entered. Given the precious nature of these samples, it is also apparent that laboratory techniques need to be made as efficient as possible in order to maximize the information that we can gain from these unique and invaluable specimens. To determine the chemical and isotopic compositions of these samples, it is often necessary to separate and purify elements of cosmochemical interest from the host rocks. A widely used method for the chemical separation of elements, following sample digestion, is through column chromatography techniques.

Of all documented planetary bodies such as Mars, Vesta, and the angrite parent-body (APB), Earth is the most oxidized [1]. Understanding how and when Earth's mantle acquired its present redox conditions is a major standing question in planetary sciences. Previsous studies have suggested that iron isotopes could be good tracers of redox conditions during melting [2]. Terrestrial basalts, as well as more felsic rocks, tend to have heavy iron isotopic composition relative to chondrites and Earth’s mantle [2, 3 and references therein]. For example, the average MORB δ^(56)Fe value is ~+0.1 ‰ while chondrites have δ^(56)Fe~+0 ‰ (Fig. 1). In contrast, basalts from Mars and Vesta have Fe isotopic compositions identical to chondrites within uncertainty. Three interpretations have been proposed to explain this feature: (1) during the Moon-forming giant impact, some isotopically light Fe was evaporated, leaving a residue enriched in heavy Fe isotopes [4]; (2) equilibriation between metal and high-pressure phases such as ferropericlase and post-perovskite created iron isotopic fractionation in Earth's mantle [5]; or (3) the isotopic composition measured in crustal rocks from Earth was produced by equilibrium or kinetic isotope fractionation between mantle peridotite and melt [2,6,7]. This poses several critical questions. What aspect of the melting process produces Fe isotopic fractionation? Why does melting on Earth or the APB fractionate Fe isotopes while on Mars and Vesta such fractionation is absent?

Significant ^(238)U/^(235)U variations have been documented in meteoritic [e.g. 1-4] and terrestrial [5] samples, which can affect Pb-Pb ages. In most cases, the cause of these variations is not understood. Here, we report an extensive study of the U isotopic composition of planetary crustal rocks. Determination of ^(238)U/^(235)U ratio in angrites is critical to establish their age: an important anchor in early solar system chronology [6,7]. The extent to which the protolith of terrestrial granites affects their U isotopic composition is unknown. We report high-precision U isotope measurements of angrites and terrestrial granites to address these two outstanding questions in solar system chronology and crustal differentiation.

Observations of variations in the ^(238)U/^(235)U ratio at the 0.1‰ level in both terrestrial [1] and meteoritic samples [e.g. 2-5], challenged the assumption of a constant ^(238)U/^(235)U ratio throughout the solar system (SS). The light isotopic compositions measured in some CAIs could be due to the presence of live ^(247)Cm in the early SS as this short-lived radionuclide decays into ^(235)U with a half-life t_(1/2)=15.6Myr. The most immediate consequence of these variations is that the isotopic composition of uranium has to be measured in each CAI to get accurate Pb-Pb ages [5,6]. Given the scale of the variations, achieving high precision measurements is necessary to fully resolve compositional differences between samples and to be able to use the potential of the U isotopic system in terrestrial and extraterrestrial samples.