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Additive manufacturing processes have attracted broad attention in the last decades since the related freedom of design allows the manufacturing of parts with unique microstructures and unprecedented complexity in shape. Focusing on the properties of additively manufactured parts, major efforts are made to elaborate process-microstructure relationships. For instance, the inevitable thermal cycling within the process plays a significant role in microstructural evolution. Various driving forces contribute to the final grain size, boundary character, residual stress state, etc. In the present study, the properties of commercially pure iron processed on three different routes, i.e., hot rolling as a reference, electron powder bed fusion, and laser powder bed fusion, using different raw materials as well as process conditions, are compared. The manufacturing of the specimens led to five distinct microstructures, which differ significantly in terms of microstructural features and mechanical responses. Using optical and electron microscopy as well as transmission electron microscopy, the built specimens were explored in various states of a tensile test in order to reveal the microstructural evolution in the course of quasistatic loading. The grain size is found to be most influential in enhancing the material’s strength. Furthermore, substructures, i.e., low-angle grain boundaries, within the grains play an important role in terms of the homogeneity of strain distribution. On the contrary, high-angle grain boundaries are found to be regions of strain localization. In summary, a holistic macro-meso-micro-nano investigation is performed to evaluate the behavior of these specific microstructures.

Introduction/BackgroundCytoreductive surgery (CRS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC) with cisplatin is a widely used strategy in the treatment of ovarian carcinomatosis. Although it seems to improve the patients‘ survival, one of its most important adverse effects is postoperative acute kidney injury (AKI). The aim of our study was to assess the incidence and identify the predictive risk factors of AKI after CRS and cisplatin-based HIPEC.MethodologyThis is a retrospective study from two centres evaluating patients with advanced or recurrent ovarian cancer who underwent CRS followed by cisplatin-based HIPEC from January 2007 to December 2013. Patients were classified in two groups according to the occurrence of AKI, defined when glomerular filtration rate at postoperative day-7 was 25% lower than at day-0. We also evaluated AKI following Risk, Injury, Failure, Lost and End-stage kidney function criteria. Univariate and multivariate analyses were conducted in order to assess the association between different variables and AKI occurrence.ResultsSixty-six patients were included: 29 (44%) underwent first-line treatment while 37 (56%) were treated for recurrent disease. The incidence of postoperative AKI was 48%. Table 1 displays the univariate analysis. After multivariate analysis, hypertension (OR 18.6; 95% CI 1.9–182.3; p=0.012) and low intraoperative diuresis (OR 0.5; 95% CI 0.4–0.8; p=0.001) were associated with AKI occurrence.ConclusionThe incidence of AKI after CRS and cisplatin-based HIPEC was high. Hypertension and low intraoperative diuresis were independent risk factors for this complication. An adequate perioperative hydration, in order to maintain a correct diuresis, could decrease acute kidney injury occurrence in patients undergoing CRS plus HIPEC. Table 2 shows general recommendations to decrease this complication.DisclosureNothing to disclose.

In additive manufacturing, the thermal history of a part determines its final microstructural and mechanical properties. The factors leading to a specific temperature profile are diverse. For the integrity of a parameter setting established, periphery variations must also be considered. In the present study, iron was processed by electron beam powder bed fusion. Parts realized by two process runs featuring different build plate sizes were analyzed. It is shown that the process temperature differs significantly, eventually affecting the properties of the processed parts.

Porosity and permeability are important properties of porous materials, such as rocks and concrete. This paper presents the physical-mathematical modelling of a novel test, based on one previously developed by one of the authors (standardized in Switzerland, Japan and China) for measuring the air-permeability of concrete structures. In the present case, a cylindrical specimen is placed inside an air-tight cell, subjected to an initial vacuum pressure P 0 , which is afterwards isolated from the pump. The rate of pressure increase (due to the extraction of air originally at atmospheric pressure P a ) is related to the coefficient of permeability of the material whilst the final pressure attained is a function of the porosity (total amount of air extracted). The analysis assumes a unidirectional radial flow of air, which can be achieved by a special serial three-chamber vacuum cell (with pressure regulation of the external chambers) or by an air-tight sealing of the extreme faces of the cylinder. The analysis is developed under the assumption of viscous laminar flow. To account for the molecular diffusion flow, the test can be performed under vacuum ( P 0 ≪ Pa ) and under overpressure ( P 0 ≫ P a ), enabling the application of the Klinkenberg correction to get the intrinsic coefficient of permeability.

The frequent presence of Fe chlorosis in plants grown on calcareous soils is influenced by the forms of soil Fe present and their contents. Previous studies suggest that temporary soil flooding may increase Fe phytoavailability. To study flooding effects in relation to microbial activity in greater depth, we incubated soil slurries in the laboratory under anoxic conditions and monitored changes in Fe mineralogy using wet chemical extractions and diffuse reflectance spectroscopy. Twenty-four calcareous soils from southern Spain ranging widely in their properties were chosen for this purpose. Slurries of sterilized and native soils were compared with those of native soils with different amendments. In contrast to the sterilized controls, most of the slurries containing native soils released substantially increased amounts of Fe(II) to the solution after 6 wk of incubation; also, the extent of Fe(II) production correlated well with native contents of dissolved organic C. Indeed, the addition of organic acids typically found in root exudates resulted in a pronounced increase in Fe(II) production, and a similar effect was observed in soil slurries additionally inoculated with Geobacter sulfurreducens, a well-known Fe(III)-reducing bacterium. Microbial Fe(III) reduction mobilized poorly crystalline and crystalline Fe oxides. The critical extractable Fe value required for Fe nutrition of tolerant plants was reached in 18 of the slurries of native soils and in 22 of the native soils amended with organic acids. Temporary flooding seems to stimulate microbial Fe(III) reduction (especially in the presence of readily available organic C), thereby effectively increasing Fe phytoavailability in calcareous soils.

The growing concerns about water eutrophication have made it urgent to restrict losses of phosphorus (P) from agricultural soils and to develop methods for predicting such losses. In this work, we used the paradigm of P sorption–desorption curves to confirm the hypothesis that the amount of dissolved reactive phosphorus (DRP) released to a dilute electrolyte tends to be proportional to the concentration of DRP in the soil solution raised to a power that decreases with increasing solution to soil ratio (W). The hypothesis was tested for a group of 12 widely ranging European agricultural soils fertilized with P in excess of crop needs. Phosphorus desorption was studied under near‐static and turbulent conditions in laboratory experiments. The concentration of DRP in the 1:1 soil to water extract (P1:1) was used as a proxy for the DRP concentration in the soil solution. The amount of desorbed P was found to be correlated with P1:1 raised to a power that decreased from 0.7 to 0.9 at W = 100 to 0.2 to 0.4 at W = 10000. Correlation was not improved by introducing additional variables related to P sorption–desorption properties. Olsen P was found to be of lower predictive value than P1:1 Also, the index of degree of soil saturation with phosphorus (DSSP) based on oxalate extraction failed to predict P desorption. The fact that P1:1 seemingly predicts P desorption accurately for a wide range of soils makes it potentially useful in areas of high soil diversity.

A bstract The Neutrino Experiment with a Xenon TPC (NEXT) searches for the neutrinoless double-beta (0 νββ ) decay of 136 Xe using high-pressure xenon gas TPCs with electroluminescent amplification. A scaled-up version of this technology with about 1 tonne of enriched xenon could reach in less than 5 years of operation a sensitivity to the half-life of 0 νββ decay better than 10 27 years, improving the current limits by at least one order of magnitude. This prediction is based on a well-understood background model dominated by radiogenic sources. The detector concept presented here represents a first step on a compelling path towards sensitivity to the parameter space defined by the inverted ordering of neutrino masses, and beyond.

Variations in the low-field magnetic susceptibility of the wind-blown Chinese Loess Plateau (CLP) loess-paleosol sequences reflect changes in the global paleoclimate on different time scales. Magnetic enhancement in paleosols has been ascribed to the neoformation of fine-grained maghemite; however, little is known about the pathway through which this mineral was formed in the CLP paleosols, its relationships with the other pedogenic Fe oxides (viz. hematite and goethite), and the pedoclimatic significance of such relationships. In this work, we characterized various magnetic, chemical, and mineralogical properties of the loess-paleosol units at depths from about 23 to 55 m in the Upper Luochuan section, central CLP. The concentration of pedogenic hematite (delta Hm) and the frequency-dependent magnetic susceptibility (chi(FD)), which is used as a proxy for the concentration of fine-grained pedogenic maghemite, were found to be linearly correlated (R2 = 0.825, P < 0.001). This supports the idea that these two minerals were formed concomitantly during pedogenesis, which is consistent with the results of previous in vitro experiments showing that the ferrihydrite to maghemite to hematite transformation takes place under aerobic conditions. By contrast, the concentration of pedogenic goethite (delta Gt) was only weakly correlated with either chi(FD) or delta Hm, which suggests that goethite formed through an alternative pathway. The paleosols above 40 m (S4, S5, corresponding to marine isotope stages 9 and 11, respectively) exhibit a higher degree of weathering and higher delta Hm/(delta Hm + delta Gt) ratio than those below such a depth (S6-S8). This was ascribed to differences in paleoclimatic conditions, which are moister and warmer in the former paleosols than in the latter, rather than to differences in pedogenesis duration.

Accurate assessment of the specific influence of calcium carbonate and iron (Fe) oxides in soil on Fe deficiency symptoms in plants has so far been made difficult by the covariance between their contents in many soils populations. In order to overcome this problem, we designed a completely randomized block experiment in which grapevine (cv. 161-49C) was pot-grown in substrates consisting of Fe oxide-coated sand (FOCS), calcium carbonate sand (CCS) and quartz sand for 100 days (five FOCS proportions, five CCS proportions, four replicates); in this way, covariance between the FOCS and CCS proportions was suppressed. An analysis of variance revealed the absence of interactions between FOCS and CCS in relation for any of the growth-related parameters studied (leaf size, increase in shoot length, internode length, and aerial biomass) and leaf chlorophyll concentration as measured via SPAD. Some growth-related parameters were found to be negatively correlated with the proportion of CCS, and leaf size to be positively correlated with the proportion of FOCS. Also, SPAD was more markedly influenced by the proportion of FOCS (positive correlation) than it was by CCS (negative correlation). Overall, these results indicate that the relative severity of the main symptoms of Fe deficiency, growth depression and leaf chlorosis, may differ from one case to another in response to the relative contents in carbonate and Fe oxides of soil. Also, they suggest the need to develop and calibrate soil tests capable of predicting the various Fe deficiency symptoms.

Timing of chest tube (CT) removal after transition from suction to water-seal (WS) varies when treating traumatic simple pneumothoraces (PTXs). Longer periods of WS may identify slow-occurring PTXs reducing CT replacement, whereas shorter periods may expedite patient disposition and have associated cost savings. Prior studies support the need for an interval of WS. We compare durations of WS, looking at rates of CT reinsertion. A 10-year retrospective review on trauma patients with a simple PTX requiring a CT was performed. WS duration of 1 to 8 hours (short - SG) versus 18 to 36 hours (long - LG) were compared. Univariate analysis and multivariate logistic regression were used. Of the 2000 patient charts reviewed, 209 met the criteria, with 43 in the SG and 166 in the LG. Patient demographics and mechanism of injury were similar. There was no difference in CT replacement [6.9% (SG) vs 4.8% (LG), P 0.59]. Logistic regression revealed an increase in CT replacement if the patient ever had positive pressure ventilation (OR 4.1, CI 1.1–17, P 0.04) and if returned to suction from WS (OR 6.3, CI 1.2–28, P 0.03). Short intervals of WS do not increase CT reinsertion while decreasing the total time and morbidity associated with CT.