This work deals with the characteristics of highly segmented double-sided silicon detectors. These are fundamental parts in many new state-of-the-art particle detection systems, and therefore they ...must perform optimally. We propose a test bench that can handle 256 electronic channels with off-the-shelf equipment, as well as a detector quality control protocol to ensure that the detectors meet the requirements. Detectors with a large number of strips bring new technological challenges and issues that need to be carefully monitored and understood. One of the standard 500 μm thick detectors of the GRIT array was investigated, undergoing studies that revealed its IV curve, charge collection efficiency, and energy resolution. From the data obtained, we calculated, among other things, the depletion voltage (110 V), the resistivity of the bulk material (9 kΩ·cm), and the electronic noise contribution (8 keV). We present, for the first time, a methodology called "the energy triangle'' to visualize the effect of charge sharing between two adjacent strips and to study the hit distribution with the interstrip-to-strip hit ratio (ISR).
► Temperature promotes Maillard reaction in chitosan-based films. ► Remarkable variations in functional properties of chitosan-based films due to the effect of temperature. ► Chitosan film forming ...solutions exhibit antimicrobial activity.
Chitosan-based films for food packaging applications were prepared by casting and dried at room temperature or heat-treated in order to study functional properties and antimicrobial activity. In all cases, films were flexible and transparent, regardless of chitosan molecular weight, glycerol content, and temperature. Regarding antimicrobial activity, chitosan film forming solutions showed antimicrobial behaviour against Escherichia coli and Lactobacillus plantarum. It was also observed that the bacteriostatic property of chitosan-based films against bacteria employed in this study was notably affected by temperature. Moreover, temperature produced significant variation in the functional properties of chitosan-based films, such as colour, wettability, resistance against UV light and mechanical properties. In good agreement with this behaviour, total soluble matter (TSM), fourier transform infrared (FTIR) spectroscopy, thermo-gravimetric analysis (TGA) and X-ray diffraction (XRD) results suggested a change in the chemical structure of chitosan films, possibly due to Maillard reaction when heat treatment was used.
Abstract
Anthozoan cnidarians (corals and sea anemones) include some of the world’s most important foundation species, capable of building massive reef complexes that support entire ecosystems. ...Although previous molecular phylogenetic analyses have revealed widespread homoplasy of the morphological characters traditionally used to define orders and families of anthozoans, analyses using mitochondrial genes or rDNA have failed to resolve many key nodes in the phylogeny. With a fully resolved, time-calibrated phylogeny for 234 species constructed from hundreds of ultraconserved elements and exon loci, we explore the evolutionary origins of the major clades of Anthozoa and some of their salient morphological features. The phylogeny supports reciprocally monophyletic Hexacorallia and Octocorallia, with Ceriantharia as the earliest diverging hexacorals; two reciprocally monophyletic clades of Octocorallia; and monophyly of all hexacoral orders with the exception of the enigmatic sea anemone Relicanthus daphneae. Divergence dating analyses place Anthozoa in the Cryogenian to Tonian periods (648–894 Ma), older than has been suggested by previous studies. Ancestral state reconstructions indicate that the ancestral anthozoan was a solitary polyp that had bilateral symmetry and lacked a skeleton. Colonial growth forms and the ability to precipitate calcium carbonate evolved in the Ediacaran (578 Ma) and Cambrian (503 Ma) respectively; these hallmarks of reef-building species have subsequently arisen multiple times independently in different orders. Anthozoans formed associations with photosymbionts by the Devonian (383 Ma), and photosymbioses have been gained and lost repeatedly in all orders. Together, these results have profound implications for the interpretation of the Precambrian environment and the early evolution of metazoans.Bilateral symmetry; coloniality; coral; early metazoans; exon capture; Hexacorallia; Octocorallia photosymbiosis; sea anemone; ultraconserved elements.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Female androgenetic alopecia (FAGA) is a common cause of hair loss in women. Typically, it is characterized by a reduction of hair density on biparietal and vertex regions of the scalp with ...preservation of the anterior hair implantation line. However, it can also appear with recession of the anterior hairline known as FAGA with male pattern (FAGA-M). In these cases, it is important to consider a state of hyperandrogenism and look for other signs such as hirsutism, acne, and menstrual irregularities. A sudden onset in a postmenopausal woman must make us suspicious of an androgen-secreting tumor. We present two cases of FAGA-M secondary to an ovarian tumor that was successfully resolved after surgical treatment.
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•Sources, fate and occurrence of phthalates and BPA in aquifers have been reviewed.•Phthalates and BPA have been globally detected in groundwater reservoirs.•Landfills, sewage sludge ...and wastewater are the main sources to groundwater pollution.•Some phthalate and BPA features and soil conditions promote the transport to aquifers.•Worldwide guidelines values for drinking water vary in a wide range of concentrations.
Phthalic acid esters (PAEs) or phthalates and bisphenol A (BPA) are emerging organic contaminants (EOCs) that may harm biota and human health. Humans can be exposed to these contaminants by drinking water consumption from water sources such as groundwater. Before their presence in aquifer systems, phthalates and BPA can be found in many matrices due to anthropogenic activities, which result in long-term transport to groundwater reservoirs by different mechanisms and reaction processes. The worldwide occurrence of phthalates and BPA concentrations in groundwater have ranged from 0.1 × 10−3 to 3 203.33 µg L−1 and from 0.09 × 10−3 to 228.04 µg L−1, respectively. Therefore, the aim of this review is to describe the groundwater contamination pathways of phthalates and BPA from the main environmental sources to groundwater. Overall, this article provides an overview that integrates phthalate and BPA environmental cycling, from their origin to human reception via groundwater consumption. Additionally, in this review, the readers can use the information provided as a principal basis for existing policy ratification and for governments to develop legislation that may incorporate these endocrine disrupting compounds (EDCs) as priority contaminants. Indeed, this may trigger the enactment of regulatory guidelines and public policies that help to reduce the exposure of these EDCs in humans by drinking water consumption.
Evolutionary convergence in lignin-degrading enzymes Ayuso-Fernández, Iván; Ruiz-Dueñas, Francisco J.; Martínez, Angel T.
Proceedings of the National Academy of Sciences - PNAS,
06/2018, Letnik:
115, Številka:
25
Journal Article
Recenzirano
Odprti dostop
The resurrection of ancestral enzymes of now-extinct organisms (paleogenetics) is a developing field that allows the study of evolutionary hypotheses otherwise impossible to be tested. In the present ...study, we target fungal peroxidases that play a key role in lignin degradation, an essential process in the carbon cycle and often a limiting step in biobased industries. Ligninolytic peroxidases are secreted by wood-rotting fungi, the origin of which was recently established in the Carboniferous period associated with the appearance of these enzymes. These first peroxidases were not able to degrade lignin directly and used diffusible metal cations to attack its phenolic moiety. The phylogenetic analysis of the peroxidases of Polyporales, the order in which most extant wood-rotting fungi are included, suggests that later in evolution these enzymes would have acquired the ability to degrade nonphenolic lignin using a tryptophanyl radical interacting with the bulky polymer at the surface of the enzyme. Here, we track this powerful strategy for lignin degradation as a phenotypic trait in fungi and show that it is not an isolated event in the evolution of Polyporales. Using ancestral enzyme resurrection, we study the molecular changes that led to the appearance of the same surface oxidation site in two distant peroxidase lineages. By characterization of the resurrected enzymes, we demonstrate convergent evolution at the amino acid level during the evolution of these fungi and track the different changes leading to phylogenetically distant ligninolytic peroxidases from ancestors lacking the ability to degrade nonphenolic lignin.
Transparent and colorless citric acid-incorporated fish gelatin/chitosan composite films were prepared in this work. The addition of citric acid into film forming formulations slowed down the ...swelling rate and swelling values of the films, which maintained their integrity and resulted in flexible hydrated films. Furthermore, citric acid acted as plasticizer, increasing the elongation at break of the films. Additionally, films showed good UV barrier properties and the incorporation of citric acid and chitosan reduced the E. coli growth, especially for the films prepared with 20 wt % citric acid, highlighting the potential use of these films as active food packaging. These results were related to the changes observed by Fourier transform infrared (FTIR) analysis, which revealed the different protein structure achieved as a function of citric acid and chitosan contents.
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•Transparent and colorless monolayer citric acid-incorporated gelatin/chitosan films.•Citric acid content greatly affected the protein structure.•Citric acid addition decreased the film swelling.•Chitosan improved the antibacterial activity of films.•Resistant, flexible and hydrophobic films were developed.
Leptin action in normal and pathological pregnancies Pérez‐Pérez, Antonio; Toro, Ayelén; Vilariño‐García, Teresa ...
Journal of cellular and molecular medicine,
February 2018, Letnik:
22, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Leptin is now considered an important signalling molecule of the reproductive system, as it regulates the production of gonadotrophins, the blastocyst formation and implantation, the normal ...placentation, as well as the foeto‐placental communication. Leptin is a peptide hormone secreted mainly by adipose tissue, and the placenta is the second leptin‐producing tissue in humans. Placental leptin is an important cytokine which regulates placental functions in an autocrine or paracrine manner. Leptin seems to play a crucial role during the first stages of pregnancy as it modulates critical processes such as proliferation, protein synthesis, invasion and apoptosis in placental cells. Furthermore, deregulation of leptin levels has been correlated with the pathogenesis of various disorders associated with reproduction and gestation, including polycystic ovary syndrome, recurrent miscarriage, gestational diabetes mellitus, pre‐eclampsia and intrauterine growth restriction. Due to the relevant incidence of the mentioned diseases and the importance of leptin, we decided to review the latest information available about leptin action in normal and pathological pregnancies to support the idea of leptin as an important factor and/or predictor of diverse disorders associated with reproduction and pregnancy.
Mentoring demonstrably increases the retention of undergraduate and graduate students and is moreover invaluable in shaping and nurturing academic careers. With the increasing diversification of the ...student body and of faculty ranks, there's a clear need for culturally responsive mentoring across these dimensions. Recognizing the low priority that academia has generally given to extending the practice of mentoring -- let alone providing mentoring for Black, indigenous, and people of color (BIPOC) and first generation students -- this book offers a proven and holistic model of mentoring practice, developed in the field of psychology, that not only helps mentees navigate their studies and the academy but provides them with an understanding of the systemic and racist barriers they will encounter, validates their cultural roots and contributions, and attends to their personal development. Further recognizing the demands that mentoring places on already busy faculty, the model addresses ways of distributing the work, inviting White and BIPOC faculty to participate, developing mentees' capacities to mentor those that follow them, building a network of mentoring across generations, and adopting group mentoring. Intentionally planned and implemented, the model becomes self-perpetuating, building an intergenerational cadre of mentors who can meet the growing and continuing needs of the BIPOC community. Opening with a review of the salient research on effective mentoring, and chapters that offer minority students' views on what has worked for them, as well as reflections by faculty mentors, the core of the book describes the Freedom Train model developed by the father of Black psychology, Dr. Joseph White, setting out the principles and processes that inform the Multiracial / Multiethnic / Multicultural (M3) Mentoring Model that evolved from it, and offers an example of group mentoring. While addressed principally to faculty interested in undertaking mentoring, and supporting minoritized students and faculty, the book also addresses Deans and Chairs and how they can create Freedom Train communities and networks by changing the cultural climate of their institutions, providing support, and modifying faculty evaluations and rewards that will in turn contribute to student retention as well as creative and productive scholarship and research. This is a timely and inspiring book for anyone in the academy concerned with the success of BIPOC students and invigorating their department's or school's scholarship. Foreword written by Nayeli Y. Chavez-Dueñas and Hector Y. Adames.
Neurodegeneration with brain iron accumulation (NBIA) is a group of inherited heterogeneous neurodegenerative rare disorders. These patients present with dystonia, spasticity, parkinsonism and ...neuropsychiatric disturbances, along with brain magnetic resonance imaging (MRI) evidence of iron accumulation. In sum, they are devastating disorders and to date, there is no specific treatment. Ten NBIA genes are accepted: PANK2, PLA2G6, C19orf12, COASY, FA2H, ATP13A2, WDR45, FTL, CP, and DCAF17; and nonetheless, a relevant percentage of patients remain without genetic diagnosis, suggesting that other novel NBIA genes remain to be discovered. Overlapping complex clinical pictures render an accurate differential diagnosis difficult. Little is known about the pathophysiology of NBIAs. The reported NBIA genes take part in a variety of pathways: CoA synthesis, lipid and iron metabolism, autophagy, and membrane remodeling. The next‐generation sequencing revolution has achieved relevant advances in genetics of Mendelian diseases and provide new genes for NBIAs, which are investigated according to 2 main strategies: genes involved in disorders with similar phenotype and genes that play a role in a pathway of interest. To achieve an effective therapy for NBIA patients, a better understanding of the biological process underlying disease is crucial, moving toward a new age of precision medicine.
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