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• Single and repeated dose of mammography can induce DSB in non-tumorigenic cell line, MCF-10A. • Repeated dose of mammography induces more DSB in tumor cell line MCF-7 and MDA-MB-231. • Breast cells have different responses to equal doses of mammographic screening. • Repeated MGD, was able to generate DSB-compatible lesions in the DNA molecule. Mammography is the diagnostic imaging practice used in screening to detect early lesions suspected of malignancy. It uses a low energy X-ray beam in which a low dose in the order of 2–3 mGy is delivered to patient breast cells. However, it has been speculated that it could lead to significant cell damage, when compared to conventional X-ray. We investigated the biological effects of low doses, with mean glandular doses (MGDs) of 2.5 mGy and 2.5 + 2.5 mGy, on mammary cells in vitro. We used the non-tumorigenic cell line (MCF-10A) and two tumor cells lines (MCF-7 and MDA-MB-231). Colony formation, apoptosis, and double-strand DNA breaks (DSBs) were quantified. The selected MGD regimens did not alter the formation of colonies by any of the cell lines. MCF-7 cells exhibited a markedly increase in apoptosis, 24 h after the single-dose protocol; MCF-10A cells underwent apoptosis only after 72 h, with both irradiation regimens, while MDA-MB-231 cells (highly invasive and metastatic) were not susceptible to apoptosis. The detection of γH2AX histone in the nuclei of irradiated cells showed that the double-dose resulted in increase of DSBs, especially in tumor cell lines. Although the health benefits of early breast screening remain indisputable, our future perspective is to better understand the biological basis for the effects of low dose radiation on breast cells and to investigate if and under what conditions there would be a risky situation in repeated mammography screening, in both asymptomatic and symptomatic women. [ABSTRACT FROM AUTHOR]

Our objectives were to determine the effects of an injectable formulation of calcitriol on mineral metabolism and immune function in postpartum Holstein cows that received an acidogenic diet prepartum to minimize hypocalcemia. In experiment 1, cows within 6 h of calving received calcitriol (0, 200, or 300 µg) to determine the dose needed to increase plasma concentrations of Ca; 300 µg was sufficient to sustain Ca for at least 3 d. In experiment 2, multiparous cows were assigned randomly to receive only vehicle (control, n = 25) or 300 µg of calcitriol (n = 25) subcutaneously within the first 6 h after calving. Blood was sampled before treatment and 12 h later, then daily until 15 d in milk (DIM), and analyzed for concentrations of ionized Ca (iCa), total Ca (tCa), total Mg (tMg), and total P (tP), metabolites, and hormones. Urine was sampled in the first 7 DIM and analyzed for concentrations of tCa, tMg, and creatinine. Neutrophil function was evaluated in the first week postpartum. Dry matter intake and production performance were evaluated for the first 36 DIM. Calcitriol administration increased concentrations of calcitriol in plasma within 12 h of application from 51 to 427 pg/mL, which returned to baseline within 5 d. Concentrations of iCa and tCa increased 24 h after treatment with calcitriol. Concentrations of iCa (control = 1.08 vs. calcitriol = 1.20 mM), tCa (control = 2.23 vs. calcitriol = 2.33 mM), and tP (control = 1.47 vs. calcitriol = 1.81 mM) remained elevated in cows treated with calcitriol until 3, 5, and 7 DIM, respectively, whereas concentration of tMg (control = 0.76 vs. calcitriol = 0.67 mM) was less in calcitriol cows than control cows until 3 DIM. Concentrations of parathyroid hormone decreased in calcitriol cows compared with control cows (control = 441 vs. calcitriol = 336 pg/mL). Calcitriol tended to increase plasma concentrations of β-hydroxybutyrate and serotonin, but concentrations of glucose, nonesterified fatty acids, and C-telopeptide of type I collagen in plasma did not differ between treatments. Cows treated with calcitriol excreted more urinary tCa (control = 0.5 vs. calcitriol = 2.1 g/d) and tMg (control = 4.5 vs. calcitriol = 5.0 g/d) in the first 7 and 2 DIM, respectively, than control cows. Compared with control, calcitriol improved the proportion of neutrophils with oxidative burst (control = 31.9 vs. calcitriol = 40.6%), mean fluorescence intensity for oxidative burst (control = 90,900 vs. calcitriol = 99,746), and mean fluorescence intensity for phagocytosis (control = 23,887 vs. calcitriol = 28,080). Dry matter intake, yields of milk, and milk components did not differ between treatments. Administration of 300 µg of calcitriol at calving was safe and effective in increasing blood concentration of iCa and plasma concentrations of calcitriol, tCa, and tP for the first 6 d after treatment, and improved measures of innate immune function in early-lactation Holstein cows. [ABSTRACT FROM AUTHOR]

As a result of the globalization, express cargo volume is rising every year. On the one hand, time-critical and highly valuable goods need to be delivered as quickly as possible. On the other hand, cities are facing multiple problems regarding their transportation system, such as increasing congestion on the roads, and air pollution. To serve the demand of express parcels and at the same time oppose these emerging challenges, an airborne "green" supply chain with low-emission vehicles can be a solution. This paper outlines the conceptual requirements of an airborne-supplied city hub that are related to urban integration, road traffic access and flight operations. First, we identified existing city hub and drone concepts in the literature. The findings were organized into a process chain. A concept for an airborne-supplied city hub was developed where the city hub serves as a transshipment center in the supply chain. For this specific research framework and the legal situation in Germany, we examined a list of mandatory and favorable requirements that may serve as a guideline for developers and providers of this new type of airborne express cargo services. • The concept for airborne-supplied city hubs is derived from ground-based supplied city hubs. • It is recommended to set up the city hub as a "white label" solution. • The development of each city hub depends on the integration into the according supply chain. • To date, the legal framework for drone landing pads at city hubs is based on helicopter guidelines. • Airborne-supplied city hubs help improve air quality in cities by supporting electric vehicles. [ABSTRACT FROM AUTHOR]

Porous media investigation by X-ray microtomography allows obtaining valuable quantitative and qualitative information, while preserving sample integrity. Modern X-ray nanotomography or Synchrotron radiation systems may distinguish structures sized only hundreds of nanometers. However, pores sized less than a few microns (microporosity) may be undetectable due to the system’s spatial resolution and noise in microfocus sources, compromising the quality of the measurement. In this study a dual-energy methodology was developed to generate density-based images from two scans made at two different voltages (80 kV and 130 KV) with a microfocus bench-top microtomography system. The images obtained were quantized in 256 gray levels, where the lowest value (zero) corresponded to voids and the highest value (255) corresponded to the densest regions mapped. From density images and single energy images, porosity was evaluated and compared. Results indicate that density images present better results than single energy images when both are compared with porosity obtained by the helium injection method. In addition, images acquired in dual-energy show good agreement with the sample’s real density values. [ABSTRACT FROM AUTHOR]

Microbial biofilm has already being used to remove metals and other pollutants from wastewater. In this sense, our proposal was to isolate and cultivate bacteria consortia from mangrove’s sediment resistant to Zn (II) and Cu (II) at 50 mg L −1 and to observe, through synchrotron X-ray fluorescence microscopy (microXRF), whether the biofilm sequestered the metal. The biofilm area analyzed was 1 mm 2 and a 2D map was generated (pixel size 20×20 μm 2 , counting time 5 s/point). The biofilm formation and retention followed the sequence Zn>Cu. Bacterial consortium zinc resistant formed dense biofilm and retained 63.83% of zinc, while the bacterial consortium copper resistant retained 3.21% of copper, with lower biofilm formation. Dehydrogenase activity of Zn resistant bacterial consortium was not negatively affect by 50 mg ml −1 zinc input, whereas copper resistant bacterial consortium showed a significant decrease on dehydrogenase activity (50 mg mL −1 of Cu input). In conclusion, biofilm may protect bacterial cells, acting as barrier against metal toxicity. The bacterial consortia Zn resistant, composed by Nitratireductor spp. and Pseudomonas spp formed dense biofilm and sequestered metal from water, decreasing the metal bioavailability. These bacterial consortia can be used in bioreactors and in bioremediation programs. [ABSTRACT FROM AUTHOR]

Microtomographic (µCT) and thin section (TS) images were analyzed and compared regarding porosity and its distribution along the samples. The results show that µCT, although limited by its resolution, shows relevant information about the distribution of porosity and quantification of connected and non-connected pores. TS have no limitations concerning resolution, but are limited by the experimental data and can only give information about connected pores. These two methods have their own advantages but when paired together they are able to make for a more complete analysis. [ABSTRACT FROM AUTHOR]

Abstract: Dual energy technique for computerized microtomography shows itself as a promising method for identification of mineralogy on geological samples of heterogeneous composition. It can also assist with differentiating very similar objects regarding the attenuation coefficient, which are usually not separable during image processing and analysis of microtomographic data. Therefore, the development of a feasible and applicable methodology of dual energy in the analysis of microtomographic images was sought. [Copyright &y& Elsevier]

Abstract: Bone quality is an evaluation index often applied in order to interpret clinical observations made upon bone health, such as bone mineral density, micro and macro architecture, and mineral content. Conventional inspection techniques do not provide full information on trabecular bone quality. This study shows the high resolution potential and the non-destructive character of X-ray microtomography and microfluorescence upon the application of such techniques for evaluating bone quality. The mineral content assessment was performed by two-dimensional concentration mappings of calcium, zinc, and strontium. The results showed significant changes in bone morphology. [Copyright &y& Elsevier]

Abstract: Characterization of trabeculae structures is one of the most important applications of imaging techniques in the biomedical area. The aim of this study was to investigate structure modifications in trabecular and cortical bones using non destructive techniques such as X-ray microtomography, X-ray microfluorescence by synchrotron radiation and scanning electron microscopy. The results obtained reveal the potential of this computational technique to verify the capability of characterization of internal bone structures. [Copyright &y& Elsevier]

Abstract: In recent years, the 3D X-ray microcomputed tomography (3DμCT) has become a useful method to access the internal geometry based microarchitecture of bones. All measurements are based on the image quality. In this context, the aim of this work is to investigate bone quality in terms of strength parameters determined by 3DμCT. The system that was used to do the 3DμCT was a microfocus Fein Focus which has a microfocus X-ray tube, adjustment of the magnification factor of the captured image by mobile supports and an image intensifier with a diameter of 9in. The results show that microtomography by microfocus X-ray tube is a powerful technique that can be used to analyze bone microstructures. A quantification procedure conducted with a locally developed program, produced images with 20μm of resolution for different bone samples. [Copyright &y& Elsevier]

Abstract: The abnormal accumulation or deficiency of trace elements may theoretically impair the formation of bone and contribute to osteoporosis. In this context, the knowledge of major and trace elements is very important in order to clarify many issues regarding diseases of the bone, such as osteoporosis, that remain unresolved. Several kinds of imaging techniques can be useful to access morphology and the minerals present in osteoporotic bones. In this work, synchrotron radiation X-ray microfluorescence was used as an X-ray imaging technique to investigate bone structures. Therefore, this research aims to improve the knowledge about some aspects of bone quality. The measurements were carried out at the Brazilian Synchrotron Laboratory Light Laboratory, in Brazil. A white beam with an energy range of 4–23keV, a 45°/45° geometry and a capillary optics were used. It was demonstrated that bone quality can and must be evaluated not only by considering the architecture of bones but also by taking into account the concentration and the distribution of minerals. Our results showed that the elemental distributions in bone zones on a micron scale were very helpful to understand functions in those structures. [Copyright &y& Elsevier]

Abstract: In this work, two X-ray techniques used were 3D microcomputed tomography (micro-CT) and X-ray microfluorescence (micro-XRF) in order to investigate the internal structure of the bone samples. Those two techniques work together, e.g. as a complement to each other, to characterize bones structure and composition. Initially, the specimens were used to do the scan procedure in the microcomputer tomography system and the second step consists of doing the X-ray microfluorescence analysis. The results show that both techniques are powerful methods for analyzing, inspecting and characterizing bone samples: they are alternative procedures for examining bone structures and compositions and they are complementary. [Copyright &y& Elsevier]

Abstract: The study of trabecular structures is important for understanding the mechanism of alcohol related to bone changes. Alcohol consumption can compromise the body mineral composition, affecting the bone metabolism and compromising the skeleton. The effects of the ethanol treatment on the internal microarchitecture of bone samples through 3D microcomputed tomography are shown in this study. The data was acquired from a radiographic system with a micro focus X-ray conic beam and it was used the Feldkamp''s technique was used to carry out the 3D reconstructions. The measured microstructure parameters, which were based on stereological concepts, were bone volume fraction, relationship between bone surface and volume, trabecular number, separation and thickness. The results show that this technique is able to analyze these kinds of structures, especially rat bone, as these structures in rats (trabecular diameter) are thinner than in human bones. [Copyright &y& Elsevier]

Abstract: Mussels are susceptible to numerous toxicants and are often employed as bioindicators. This study investigated the status of the ras proto-oncogene in Mytilus galloprovincialis following petrochemical exposure. A M. galloprovincialis homologue of the vertebrate ras gene was isolated, showing conserved sequence in regions of functional importance and a high incidence of polymorphic variation. Mutational damage was investigated in mussels chronically exposed to the water-accommodated fraction of #4 fuel-oil (WAF), and in mussels collected along the NW coast of Portugal in sites with different levels of petrochemical contamination. A ras gene point mutation was identified in the codon 35 of one individual exposed to 12.5% WAF. No mutations were detected in mussels from the WAF control or environmental samples. This represents the first report of a ras gene mutation, experimentally-induced by petrochemical exposure, in an invertebrate species. [Copyright &y& Elsevier]

Abstract: The objective of this study is to evaluate the quantification process of geometric parameters when different computed microtomography spatial resolutions are employed. To this end, one reservoir rock sample was scanned with a 3D high energy computed microtomography system. The results show a strong difference in the acquisition, reconstruction and image processes, but do not present a significant loss of information on the microstructural parameters in the higher resolutions. However, it has been significantly loss of information in the lower resolution. [Copyright &y& Elsevier]

Abstract: Characterization of porosity in carbonate rocks is important in the oil and gas industry since a major hydrocarbons field is formed by this lithology and they have a complex media porous. In this context, this research presents a study of the pore space in limestones rocks by x-ray microtomography. Total porosity, type of porosity and pore size distribution were evaluated from 3D high resolution images. Results show that carbonate rocks has a complex pore space system with different pores types at the same facies. [Copyright &y& Elsevier]

Porous space characterization of carbonate rocks is an important aid in petroleum exploration from carbonate reservoir. In this study, X-ray microtomography technique was applied to evaluate total porosity of a coquina sample extracted from pre-salt reservoir, in Brazil, before and after acid injection. Two image processing program were used in order to assess performance. The results showed that microtomography has potential to compute porosity of coquina samples and provides information about rock porous network. [ABSTRACT FROM AUTHOR]

Nonunion fractures occur frequently in humans, with profound implications (medical and non-medical). Although there are numerous animal models to study pathogenesis and treatment of nonunion fractures, there is apparently the lack of a definitive model for atrophic nonunion fracture. Therefore, the objective was to develop a low-cost rat model of nonunion fracture with a vascular deficit that enabled standardized quantitative analysis of bone growth and regeneration. The model was developed with two surgeries, performed apart. The first involved osteotomy of the femur diaphysis, removal of periosteum and endosteum, isolation of the fracture site using a latex artefact (Penrose drain tube), and reduction of the fracture using an intramedullary pin, whereas the second surgery was to remove the latex artefact. Based on radiographic imaging, micro-CT and histological analyses done 125 days after the fracture was induced, there was clear evidence of atrophic nonunion fracture, without pin migration or specimen loss. Perceived advantages of this model included low cost, ease of reproducibility, lack of specimen loss, and, finally, the potential to assess bone growth and regeneration under poor vascular conditions. [ABSTRACT FROM AUTHOR]

Acid treatments are used in the oil and gas industry, to increase the permeability of the carbonate reservoirs by creating preferential channels, called wormholes. Channels formation is strongly influenced by acid type and injection rate. The aim of this study is to evaluate some characteristics of the microporous system of carbonate rocks, before and after acidizing. For that purpose X-ray high-resolution microtomography was used. The results show that this technique can be used as a reliable method to analyze microstructural characteristics of the wormholes. [ABSTRACT FROM AUTHOR]

Abstract: An X-ray transmission microtomography (CT) system combined with an X-ray fluorescence microtomography (XRFμCT) system was implemented in the Brazilian Synchrotron Light Laboratory (LNLS), in order to determine the elemental distribution in prostate samples aiming at establishing a correlation between the concentration of some elements and the characteristics and pathology of the tissues. The CT images were reconstructed using a filtered-back projection algorithm and the XRFμCT images were reconstructed using a filtered-back projection algorithm with absorption corrections. [Copyright &y& Elsevier]

Arsenic (As) and antimony (Sb) are potentially hazardous metalloids and their presence in the environment is often related to mineral deposits, mines, and thermal springs. Despite their similar chemical properties, the distribution and behavior of As and Sb in nature has been shown to differ. In order to contribute to a better understanding of As and Sb in the environment as well as the important parameters controlling their mobility, this study presents a synthesis of geochemical results in the Altiplano-Puna of Chile and Bolivian Sb belt. Analyses include (i) solid-state partitioning, (ii) mineralogical studies and (iii) concentrations of both metalloids in groundwater, surface water, porewater, and fluvial and lake sediments in distinct seasons. Consistencies were found between the mobilization patterns of As and Sb in the studied sites where As is generally more mobile than Sb; however, mining-affected areas in the Bolivian Sb belt tend to be associated with a higher proportion of mobile Sb. From a mineralogical standpoint, As is generally associated with iron oxides and hydroxides and As-bearing pyrites, while Sb is linked to iron oxides, hydroxides, and clay-sized phyllosilicates. When compared to different metallogenic settings outside the Altiplano-Puna plateau (the Loa River Basin of northern Chile and Xikuangshan Mine in China), the following conclusions are consistent with the results obtained from the Altiplano-Puna: dissolved Sb concentrations tend to decrease with distance from the respective mining facility, the mobility of Sb is typically lower than As, and the preferred mineralogical associations are iron oxides and hydroxides. Finally, based on the seasonal analysis of As and Sb, it is conceptualized that wetlands behave as a source of As and as a sink and source of Sb depending on the water column; in addition, consideration must be taken regarding aeolian weathering. [Display omitted] • Arsenic and Sb were analyzed in distinct environments, including the Bolivian Sb belt. • Arsenic generally presents increased partitioning and concentrations when compared to Sb. • At mining-affected sites, Sb is more partitioned and highly concentrated. • Main mineral associations with As include iron oxides, hydroxides, silicates, and sulfides. • Main mineral associations with Sb include iron oxides, hydroxides, and phyllosilicates. [ABSTRACT FROM AUTHOR]

Abstract: In recent years, bone quantification led to a deeper knowledge of the 3D microarchitecture. In this study the bone architecture of rats was investigated based on 2D/3D morphometric analysis using microcomputed tomography, aiming at determining the effect of the image acquisition pixel on the quality of some 2D/3D morphometric parameters, such as porosity and trabecular density. Six pairs of bone samples were used and the scans were carried out using high microcomputed tomography system, operating at three different pixel sizes of 33.3μm, 15.0μm and 9.5μm. The results showed 2D parameters values lower than those obtained in the 3D analysis, mainly for trabecular density, separation and thickness. [Copyright &y& Elsevier]