The supergiant fast X-ray transients XTE J1739-302 and IGR J08408-4503 in quiescence with XMM-Newton

Context. Supergiant fast X-ray transients are a subclass of high mass X-ray binaries that host a neutron star accreting mass from the wind of its OB supergiant companion. They are characterized by an extremely pronounced and rapid variability in X-rays, which still lacks an unambiguous interpretation. A number of deep pointed observations with XMM-Newton have been carried out to study the quiescent emission of these sources and gain insight into the mechanism that causes their X-ray variability. Aims. We continued this study by using three XMM-Newton observations of the two supergiant fast X-ray transient prototypes XTEJ1739-302 and IGR J08408-4503 in quiescence. Methods. An in-depth timing and spectral analysis of these data have been carried out. Results. We found that the quiescent emission of these sources is characterized by both complex timing and spectral variability, with multiple small flares occurring sporadically after periods of lower X-ray emission. Some evidence is found in the XMM-Newton spectra of a soft component below ~2 keV, similar to that observed in the two supergiant fast X-ray transients AXJ1845.0-0433 and IGRJ16207-5129 and in many other high mass X-ray binaries. Conclusions.We suggest some possible interpretations of the timing and spectral properties of the quiescent emission of XTEJ1739- 302 and IGR J08408-4503 in the context of the different theoretical models proposed to interpret the behavior of the supergiant fast X-ray transients.Comment: 13 pages, 14 figures. Accepted for publication in A&A. V2: Corrected few typo

Image Content Enhancement Through Salient Regions Segmentation for People With Color Vision Deficiencies

Color vision deficiencies affect visual perception of colors and, more generally, color images. Several sciences such as genetics, biology, medicine, and computer vision are involved in studying and analyzing vision deficiencies. As we know from visual saliency findings, human visual system tends to fix some specific points and regions of the image in the first seconds of observation summing up the most important and meaningful parts of the scene. In this article, we provide some studies about human visual system behavior differences between normal and color vision-deficient visual systems. We eye-tracked the human fixations in first 3 seconds of observation of color images to build real fixation point maps. One of our contributions is to detect the main differences between the aforementioned human visual systems related to color vision deficiencies by analyzing real fixation maps among people with and without color vision deficiencies. Another contribution is to provide a method to enhance color regions of the image by using a detailed color mapping of the segmented salient regions of the given image. The segmentation is performed by using the difference between the original input image and the corresponding color blind altered image. A second eye-tracking of color blind people with the images enhanced by using recoloring of segmented salient regions reveals that the real fixation points are then more coherent (up to 10%) with the normal visual system. The eye-tracking data collected during our experiments are in a publicly available dataset called Eye-Tracking of Color Vision Deficiencies

Localization of volatile acidity reducing factors in grape

Must clarification processes cause an increase in the acetate content of wine at the end of the alcoholic fermatation process, this phenomenon being particularly noticeable when fermentation is obtained by means of the so-called 'high acetate-producer' yeast strains. The influence of different must fractions (free run juice, pressed juice, skins and seeds) on acetate production in white grape was investigated, and the addition of skins and and seeds to a synthetic nutritive medium (MNS) was seen to cause a considerable reduction in acetate production. Strain-related differences become evident when the grape bunch is subjected to heat shock (90°C) before musting. In such conditions, acetate content after fermentation is approximately the same as that of the control specimen (not heat treated) for the low acetate-producer strain (S191c) and higher for the high producer strain (S22b). This suggests the presence of some thermolabile factor that is responsible for inhibiting acetate production. In order to determine the chemical nature of this factor, a series of tests was performed on two substances contained in grape skins and seeds, i.e., polyphenolic compounds and unsaturated fatty acids. A reduction in acetate production was observed in the presence of both substances, their effect being greater when used in connection with high acetate-producer yeast strains

Image Content Enhancement Through Salient Regions Segmentation for People With Color Vision Deficiencies.

Color vision deficiencies affect visual perception of colors and, more generally, color images. Several sciences such as genetics, biology, medicine, and computer vision are involved in studying and analyzing vision deficiencies. As we know from visual saliency findings, human visual system tends to fix some specific points and regions of the image in the first seconds of observation summing up the most important and meaningful parts of the scene. In this article, we provide some studies about human visual system behavior differences between normal and color vision-deficient visual systems. We eye-tracked the human fixations in first 3 seconds of observation of color images to build real fixation point maps. One of our contributions is to detect the main differences between the aforementioned human visual systems related to color vision deficiencies by analyzing real fixation maps among people with and without color vision deficiencies. Another contribution is to provide a method to enhance color regions of the image by using a detailed color mapping of the segmented salient regions of the given image. The segmentation is performed by using the difference between the original input image and the corresponding color blind altered image. A second eye-tracking of color blind people with the images enhanced by using recoloring of segmented salient regions reveals that the real fixation points are then more coherent (up to 10%) with the normal visual system. The eye-tracking data collected during our experiments are in a publicly available dataset called Eye-Tracking of Color Vision Deficiencies

A joint coregistration of rotated multitemporal SAR images based on the cross-cross-correlation

Accurate synthetic aperture radar (SAR) images coregistration is on the base of several remote sensing applications, such as interferometry, change detection, etc. This paper proposes a new algorithm for jointly coregister a stack of multitemporal SAR images exploiting the cross-correlations computed for each couple of patches' cross-correlation. By doing so, the method is capable of exploit also the respective misregistration information between the slave during the estimation process. This methodology is applied to improve the performance of the constrained Least Squares (CLS) optimization method that does not account for the reciprocal information related to the slaves. Tests on real-recorded data shown the benefits of the proposed method in terms of root mean square error (RMSE) for images affected by respective rotations

Working with children who are victims of abuse: Emotions and representations of professionals in residential children's communities

Professionals who work in residential children's communities face many difficulties and, when the hosted children have a history of abuse and maltreatment, the risk of vicarious traumatization and professional burn-out, which has a negative effect on the professional's work and well-being as well as on the effectiveness at work, is very high. This qualitative study aims to explore, via the content analysis of text recorded in some Photolangage® groups, the representations of social workers and educators in residential children's communities on the theme of work management of physical and sexual abuse victims. The participants were 37 social workers from 6 residential communities for 0-6 years old child in the region of Palermo (Italy). The analysis of the discourse revealed four main themes: "emotional responses", "difficulty in coping with emotions related to abuse", "relationship with the institutional network" and "work methods/strategies", which seem to guide and inform the social workers in our daily relationship with children. These results, which are in line with clinical observations, indicate the importance of supporting, through tools such as supervision and analysis of professional practices, professionals who work with maltreated and abused children, the only way to protect their well-being and the "therapeutic role" in the care and protection of children which they fulfil

XMM-Newton observations of IGRJ18410-0535: The ingestion of a clump by a supergiant fast X-ray transient

IGRJ18410-0535 is a supergiant fast X-ray transients. This subclass of supergiant X-ray binaries typically undergoes few- hour-long outbursts reaching luminosities of 10^(36)-10^(37) erg/s, the occurrence of which has been ascribed to the combined effect of the intense magnetic field and rotation of the compact object hosted in them and/or the presence of dense structures ("clumps") in the wind of their supergiant companion. IGR J18410-0535 was observed for 45 ks by XMM-Newton as part of a program designed to study the quiescent emission of supergiant fast X-ray transients and clarify the origin of their peculiar X-ray variability. We carried out an in-depth spectral and timing analysis of these XMM-Newton data. IGR J18410-0535 underwent a bright X-ray flare that started about 5 ks after the beginning of the observation and lasted for \sim15 ks. Thanks to the capabilities of the instruments on-board XMM-Newton, the whole event could be followed in great detail. The results of our analysis provide strong convincing evidence that the flare was produced by the accretion of matter from a massive clump onto the compact object hosted in this system. By assuming that the clump is spherical and moves at the same velocity as the homogeneous stellar wind, we estimate a mass and radius of Mcl \simeq1.4\times10^(22) g and Rcl \simeq8\times10^(11) cm. These are in qualitative agreement with values expected from theoretical calculations. We found no evidence of pulsations at \sim4.7 s after investigating coherent modulations in the range 3.5 ms-100 s. A reanalysis of the archival ASCA and Swift data of IGR J18410-0535, for which these pulsations were previously detected, revealed that they were likely to be due to a statistical fluctuation and an instrumental effect, respectively.Comment: Accepted for publication on A&A. V2: Inserted correct version of Fig.1

HELLS and CDCA7 comprise a bipartite nucleosome remodeling complex defective in ICF syndrome

Mutations in CDCA7, the SNF2 family protein HELLS (LSH), or the DNA methyltransferase DNMT3b cause immunodeficiency–centro-meric instability–facial anomalies (ICF) syndrome. While it has been speculated that DNA methylation defects cause this disease, little is known about the molecular function of CDCA7 and its functional relationship to HELLS and DNMT3b. Systematic analysis of how the cell cycle, H3K9 methylation, and the mitotic kinase Aurora B affect proteomic profiles of chromatin in Xenopus egg extracts revealed that HELLS and CDCA7 form a stoichiometric complex on chromatin, in a manner sensitive to Aurora B. Although HELLS alone fails to remodel nucleosomes, we demonstrate that the HELLS–CDCA7 complex possesses nucleosome remodeling activity. Furthermore, CDCA7 is essential for loading HELLS onto chromatin, and CDCA7 harboring patient ICF mutations fails to recruit the complex to chromatin. Together, our study identifies a unique bipartite nucleosome remodeling complex where the functional remodeling activity is split between two proteins and thus delineates the defective pathway in ICF syndrome

Artificial decellularized extracellular matrix improves the regenerative capacity of adipose tissue derived stem cells on 3D printed polycaprolactone scaffolds

Ideal tissue engineering frameworks should be both an optimal biological microenvironment and a shape and stability providing framework. In this study we tried to combine the advantages of cell-derived artificial extracellular matrix (ECM) with those of 3D printed polycaprolactone (PCL) scaffolds. In Part A, both chondrogenic and osteogenic ECMs were produced by human adipose derived stem cells (hASCs) on 3D-printed PCL scaffolds and then decellularized to create cell free functionalized PCL scaffolds, named acPCL and aoPCL respectively. The decellularization resulted in a significant reduction of the DNA content as well as the removal of nuclei while the ECM was largely preserved. In Part B the bioactivation and the effect of the ac/aoPCL scaffolds on the proliferation, differentiation, and gene expression of hASCs was investigated. The ac/aoPCL scaffolds were found to be non-toxic and allow good adhesion, but do not affect proliferation. In the in vitro investigation of cartilage regeneration, biochemical analysis showed that acPCL scaffolds have an additional effect on chondrogenic differentiation as gene expression analysis showed markers of cartilage hypertrophy. The aoPCL showed a large influence on the differentiation of hASCs. In control medium they were able to stimulate hASCs to produce calcium alone and all genes relevant investigated for osteogenesis were significantly higher expressed on aoPCL than on unmodified PCL. Therefore, we believe that ac/aoPCL scaffolds have a high potential to improve regenerative capacity of unmodified PCL scaffolds and should be further investigated