233 research outputs found
Reducing the fine-tuning of gauge-mediated SUSY breaking
Despite their appealing features, models with gauge-mediated supersymmetry
breaking (GMSB) typically present a high degree of fine-tuning, due to the
initial absence of the top trilinear scalar couplings, . In this paper,
we carefully evaluate such a tuning, showing that is worse than per mil in the
minimal model. Then, we examine some existing proposals to generate
term in this context. We find that, although the stops can be made lighter,
usually the tuning does not improve (it may be even worse), with some
exceptions, which involve the generation of at one loop or tree level. We
examine both possibilities and propose a conceptually simplified version of the
latter; which is arguably the optimum GMSB setup (with minimal matter content),
concerning the fine-tuning issue. The resulting fine-tuning is better than one
per mil, still severe but similar to other minimal supersymmetric standard
model constructions. We also explore the so-called "little
problem", i.e. the fact that a large -term is normally accompanied by a
similar or larger sfermion mass, which typically implies an increase in the
fine-tuning. Finally, we find the version of GMSB for which this ratio is
optimized, which, nevertheless, does not minimize the fine-tuning.Comment: 16 pages, 11 figures, 1 appendix. Discussion extended, matches EPJC
published versio
What is a Natural SUSY scenario?
The idea of "Natural SUSY", understood as a supersymmetric scenario where the
fine-tuning is as mild as possible, is a reasonable guide to explore
supersymmetric phenomenology. In this paper, we re-examine this issue in the
context of the MSSM including several improvements, such as the mixing of the
fine-tuning conditions for different soft terms and the presence of potential
extra fine-tunings that must be combined with the electroweak one. We give
tables and plots that allow to easily evaluate the fine-tuning and the
corresponding naturalness bounds for any theoretical model defined at any
high-energy (HE) scale. Then, we analyze in detail the complete fine-tuning
bounds for the unconstrained MSSM, defined at any HE scale. We show that
Natural SUSY does not demand light stops. Actually, an average stop mass below
800 GeV is disfavored, though one of the stops might be very light. Regarding
phenomenology, the most stringent upper bound from naturalness is the one on
the gluino mass, which typically sets the present level of fine-tuning at
. However, this result presents a strong dependence on the HE
scale. E.g. if the latter is GeV the level of fine-tuning is four
times less severe. Finally, the most robust result of Natural SUSY is by far
that Higgsinos should be rather light, certainly below 700 GeV for a
fine-tuning of or milder. Incidentally, this upper bound is not
far from TeV, which is the value required if dark matter is made of
Higgsinos.Comment: 41 pages, 8 figures, 9 tables. References added, matches JHEP
published versio
Perkinsosis in molluscs: A review
The genus Perkinsus includes protistan parasites infecting marine molluscs throughout the world, some of which are associated with mass mortalities. Life cycle involves vegetative proliferation within the host, by which a cell named trophozoite undergoes successive bipartitioning. Other stages have been observed in vitro or in vivo, depending on the species: hypnospore, zoosporangium and zoospore. Molecular taxonomy supports a close affinity between dinoflagellates and Perkinsus spp. Six species of Perkinsus are currently considered valid: P. marinus, P. olseni, P. qugwadi, P. chesapeaki, P. andrewsi and P. mediterraneus. Histology and, above all, incubation of host tissues in Ray’s fluid thioglycollate medium (RFTM) are classic diagnostic methods. In addition, more sensitive and quicker molecular diagnostic techniques based on either immunoassays or PCR have been developed for Perkinsus spp. Epizootiological studies have shown a marked influence of water temperature and salinity on P. marinus infection in oysters Crassostrea virginica, thus determining parasite geographical range and temporal disease dynamics (seasonality). In vitro cultures have been established for four Perkinsus spp. Immune response to infection varies depending on host and involves phagocytosis or encapsulation of the parasite cells by host haemocytes. A polypeptide is secreted by clam Tapes philippinarum haemocytes that could kill the parasite. In vitro cultured P. marinus cells secrete proteases that are likely involved in degradation of host tissues. P. marinus can suppress the toxic oxygen radicals produced by host haemocytes. In addition to host death, sublethal effects caused by Perkinsus spp. (reduction of fecundity, growth, and condition) may have significant ecological and economic implications. Various strategies have been assayed to mitigate the consequences of P. marinus epizootics on the oyster industry: modifications of management/culture procedures, selective breeding to obtain resistant oyster strains, and the use of triploid oysters and allochthonous oyster species. Some chemotherapeutants have been proved to inhibit or kill parasite cells in vitro
Characterizing the Epigenetic and Transcriptomic Responses to Perkinsus marinus Infection in the Eastern Oyster Crassostrea virginica
© Copyright © 2020 Johnson, Sirovy, Casas, La Peyre and Kelly. Eastern oysters in the northern Gulf of Mexico are routinely infected with the protistan parasite Perkinsus marinus, the cause of the disease commonly known as dermo. Recent experimental challenges among Atlantic coast populations have identified both resistant and susceptible genotypes using comparative transcriptomics. While controlled experimental challenges are essential first assessments, expanding this analysis to field reared individuals provides an opportunity to identify key genomic signatures of infection that appear both in the laboratory and in the field. In this study we combined reduced representation bisulfite sequencing with 3′ RNA sequencing (Tag-seq) to describe two molecular phenotypes associated with infection in oysters outplanted at a common garden field site. These combined approaches allowed us to examine changes in DNA methylation and gene expression for a large number of individuals (n = 40) that developed infections during the course of a common garden outplant experiment. Our epigenetic analysis of DNA methylation identified significant changes in gene body methylation associated with increasing infection intensity, across genes associated with immune responses. There was a smaller transcriptomic response to increasing infection intensities with 32 genes showing differential expression; however, only 40% of these genes were found to also be differentially methylated. While there was no clear pattern between direction of differential methylation and gene expression, there was a significant effect of percent methylation on gene-by-gene expression levels and the coefficient of variation in gene body methylation between treatments. These results show that in C. virginica, heavily methylated genes have high levels of gene expression with low levels of variation. Comparing our differential expression results with previously published experimental P. marinus challenges identified overlapping expression patterns for genes associated with C1q-domain-containing and V-type proton ATPase proteins. Through our comparative transcriptomic approach using field reared individuals and co-expression network analysis we have also been able to identify a network of genes that change in expression in response to infection. These combined analyses provide evidence for a conserved response to P. marinus infections across infection intensities and suggest that DNA methylation may not be a reliable predictor of differential gene expression in long-term infections
Differential Spatiotemporal Patterns of Galectin Expression are a Hallmark of Endotheliochorial Placentation
Problem: Galectins influence the progress of pregnancy by regulating key processes associated with embryo-maternal cross talk, including angiogenesis and placentation. Galectin family members exert multiple roles in the context of hemochorial and epitheliochorial placentation; however, the galectin prolife in endotheliochorial placenta remains to be investigated. Method of study: Here, we used immunohistochemistry to analyze galectin (gal)-1, gal-3 and gal-9 expression during early and late endotheliochorial placentation in two different species (dogs and cats). Results: We found that during early feline gestation, all three galectin members were more strongly expressed on trophoblast and maternal vessels compared to the decidua. This was accompanied by an overall decrease of gal-1, gal-3 and gal-9 expressions in late feline gestation. In canine early pregnancy, we observed that gal-1 and gal-9 were expressed strongly in cytotrophoblast (CTB) cells compared to gal-3, and no galectin expression was observed in syncytiotrophoblast (STB) cells. Progression of canine gestation was accompanied by increased gal-1 and gal-3 expressions on STB cells, whereas gal-9 expression remained similar in CTB and STB. Conclusion: These data suggest that both the maternal and fetal compartments are characterized by a spatiotemporal regulation of galectin expression during endotheliochorial placentation. This strongly suggests the involvement of the galectin family in important developmental processes during gestation including immunemodulation, trophoblast invasion and angiogenesis. A conserved functional role for galectins during mammalian placental development emerges from these studies.Facultad de Ciencias Veterinaria
Differential Spatiotemporal Patterns of Galectin Expression are a Hallmark of Endotheliochorial Placentation
Problem: Galectins influence the progress of pregnancy by regulating key processes associated with embryo-maternal cross talk, including angiogenesis and placentation. Galectin family members exert multiple roles in the context of hemochorial and epitheliochorial placentation; however, the galectin prolife in endotheliochorial placenta remains to be investigated. Method of study: Here, we used immunohistochemistry to analyze galectin (gal)-1, gal-3 and gal-9 expression during early and late endotheliochorial placentation in two different species (dogs and cats). Results: We found that during early feline gestation, all three galectin members were more strongly expressed on trophoblast and maternal vessels compared to the decidua. This was accompanied by an overall decrease of gal-1, gal-3 and gal-9 expressions in late feline gestation. In canine early pregnancy, we observed that gal-1 and gal-9 were expressed strongly in cytotrophoblast (CTB) cells compared to gal-3, and no galectin expression was observed in syncytiotrophoblast (STB) cells. Progression of canine gestation was accompanied by increased gal-1 and gal-3 expressions on STB cells, whereas gal-9 expression remained similar in CTB and STB. Conclusion: These data suggest that both the maternal and fetal compartments are characterized by a spatiotemporal regulation of galectin expression during endotheliochorial placentation. This strongly suggests the involvement of the galectin family in important developmental processes during gestation including immunemodulation, trophoblast invasion and angiogenesis. A conserved functional role for galectins during mammalian placental development emerges from these studies.Facultad de Ciencias Veterinaria
Monitoring UF membrane performance treating surface-groundwater blends: limitations of FEEM-PARAFAC on the assessment of the organic matter role
The decrease of water quantity and quality in water scarcity areas is palliated by improving water treatments with membrane technologies. System performance and efficiency, and then cost, is mainly affected by membrane fouling, which is still not well understood and controlled appropriately. In this study, the influence of content and composition of dissolved organic matter (DOM) on a membrane ultrafiltration (UF) stage from a full-scale UF stage in a drinking water treatment plant (DWTP) fed with surface water, groundwater (or blends of them) was investigated. Excitation-emission matrix (EEM) fluorescence spectroscopy coupled with parallel factor analysis (PARAFAC) was used to characterize and assess DOM changes in water samples Water streams feeding the UF stage showed high variability in DOM content and composition. FEEM-PARAFAC analysis allowed the differentiation of seven different organic components. Additionally to the characterization and monitoring of DOM in the full-scale UF stage, a bench scale UF pilot was run to experimentally correlate the impact of water quality with membrane performance. The experiments included testing synthetic solutions of model foulants (synthetic humic acid and bovine serum albumin) and blends of complex waters. To quantify fouling, the total fouling index (TFI) and the hydraulically irreversible fouling index (HIFI) were calculated for each filtration run. According to the results obtained, the correlation plots between the PARAFAC components and the fouling indices pointed at microbial byproducts (C1) and humic-like components (C2, C4, C5) as the ones showing higher correlations
A Comparative Study of the Efficacy of an Intervention with a Nutritional Supplement for Patients with Chronic Kidney Disease: A Randomized Trial.
Chronic kidney disease (CKD) involves heterogeneous diseases that affect the renal structure and function. Malnutrition plays a crucial role during patients with CKD on hemodialysis (HD) treatment and is associated with an increased rate and duration of hospitalizations. The aim of this randomized, parallel, intervention-controlled trial was to assess whether the use of daily supplementation with a new nutritional product developed by the Grand Fontaine Laboratories improves the nutritional status and anthropometric parameters of stage 5 CKD patients, compared with standard renal dietary advice, after three months of follow-up. Dietary intake, anthropometric measurements, physical activity, and blood samples were collected at baseline and after three months of intervention. Significant improvements were observed within the intervention group in body weight (1.5 kg [95% CI: 0.9 to 2.12 kg]) and BMI (0.54 kg/m2 [95% CI: 0.31 to 0.77]; p-value between groups, 0.002 and 0.006, respectively). In the control group, significant decreases were observed in transferrin saturation (−5.04% [95% CI: −8.88 to −1.21]) and alpha-tocopherol levels (−3.31 umol/L [95% CI: −6.30 to −0.32]). We concluded that daily dietary intake of a specific renal nutritional complement in CKD patients with or at risk of malnutrition may prevent deterioration in nutritional parameters
Do sputum or circulating blood samples reflect the pulmonary transcriptomic differences of COPD patients? A multi-tissue transcriptomic network META-analysis
BACKGROUND: Previous studies have identified lung, sputum or blood transcriptomic biomarkers associated with the severity of airflow limitation in COPD. Yet, it is not clear whether the lung pathobiology is mirrored by these surrogate tissues. The aim of this study was to explore this question. METHODS: We used Weighted Gene Co-expression Network Analysis (WGCNA) to identify shared pathological mechanisms across four COPD gene-expression datasets: two sets of lung tissues (L1 n = 70; L2 n = 124), and one each of induced sputum (S; n = 121) and peripheral blood (B; n = 121). RESULTS: WGCNA analysis identified twenty-one gene co-expression modules in L1. A robust module preservation between the two L datasets was observed (86%), with less preservation in S (33%) and even less in B (23%). Three modules preserved across lung tissues and sputum (not blood) were associated with the severity of airflow limitation. Ontology enrichment analysis showed that these modules included genes related to mitochondrial function, ion-homeostasis, T cells and RNA processing. These findings were largely reproduced using the consensus WGCNA network approach. CONCLUSIONS: These observations indicate that major differences in lung tissue transcriptomics in patients with COPD are poorly mirrored in sputum and are unrelated to those determined in blood, suggesting that the systemic component in COPD is independently regulated. Finally, the fact that one of the preserved modules associated with FEV1 was enriched in mitochondria-related genes supports a role for mitochondrial dysfunction in the pathobiology of COPD
Reliability and validity study of the Spanish adaptation of the “Wijma Delivery Expectancy/Experience Questionnaire” (W-DEQ-A)
The Wijma Delivery Expectancy/Experience Questionnaire (W-DEQ-A) is an instrument that evaluates fear of childbirth through the expectations of women in relation to childbirth and their experience during the birth. The objective of this study was to translate the W-DEQ-A into Spanish and analyse its reliability and validity. The study was carried out in two phases: (1) adapting the questionnaire to Spanish and (2) a transversal study in a sample of 273 pregnant women in the Sexual and Reproductive Health centres in the Metropolitan Northern Barcelona in Catalonia (Spain). The psychometric properties were analysed in terms of reliability and construct validity. The confirmatory factorial analysis did not confirm the unidimensionality of the original structure of the WDEQ-A, as happened with the other studies in which it has previously been validated. The result of the exploratory factorial analysis suggests four factors, or dimensions, very similar but not identical to those obtained in other analysis studies of the W-DEQ-A. The Cronbach alpha and the omega scale were also adequate for all the scales and for each of the dimensions. The results of this study confirm the findings of other studies that suggest that the W-DEQ-A is multi-dimensional. In the Spanish version of the W-DEQ-A four dimensions have been identified to explore fear of childbirth in pregnant women. The Spanish version of the WDEQ-A (WDEQ-A-Sp) is reliable and valid for the measurement of fear of childbirth in clinical practice and for use in future research
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