553 research outputs found

    Fertimetro, a Principle and Device to Measure Soil Nutrient Availability for Plants by Microbial Degradation Rates on Differently-Spiked Buried Threads

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    A novel patented method (PCT/IB2012/001157: Squartini, Concheri, Tiozzo, University of Padova) and the corresponding application devices, suitable to measure soil fertility, are presented. The availability or deficiency of specific nutrients for crops is assessed by monitoring the kinetics of progressive weakening of cotton or silk threads due to in situ microbial activity. The method is based on a nutrient-primed incremented substrate degradation principle. Threads are buried as is or pre-impregnated with N or P solutions, and the acceleration of the degradation rate for the N-supplemented or P-supplemented thread, in comparison to the untreated thread, is proportional to the lack of the corresponding nutrient in that soil. Tests were validated on corn crops in plots receiving increasing fertilizer rates in a historical rotation that has been established since 1962. The measurement carried out in May significantly correlated with the subsequent crop yields recorded in October. The analysis allows an early, inexpensive, fast, and reproducible self-assessment at field level to improve fertilization rates. The device is envisaged as a user-friendly tool for agronomy, horticulture, and any environmental applications where organic matter cycling, soil quality, and specific nutrients excess or deficiency are critical considerations

    The entropy of alpha-continued fractions: numerical results

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    We consider the one-parameter family of interval maps arising from generalized continued fraction expansions known as alpha-continued fractions. For such maps, we perform a numerical study of the behaviour of metric entropy as a function of the parameter. The behaviour of entropy is known to be quite regular for parameters for which a matching condition on the orbits of the endpoints holds. We give a detailed description of the set M where this condition is met: it consists of a countable union of open intervals, corresponding to different combinatorial data, which appear to be arranged in a hierarchical structure. Our experimental data suggest that the complement of M is a proper subset of the set of bounded-type numbers, hence it has measure zero. Furthermore, we give evidence that the entropy on matching intervals is smooth; on the other hand, we can construct points outside of M on which it is not even locally monotone.Comment: 33 pages, 14 figure

    Identification of differentially expressed genes from multipotent epithelia at the onset of an asexual development

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    © The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Scientific Reports 6 (2016): 27357, doi:10.1038/srep27357.Organisms that have evolved alternative modes of reproduction, complementary to the sexual mode, are found across metazoans. The chordate Botryllus schlosseri is an emerging model for asexual development studies. Botryllus can rebuild its entire body from a portion of adult epithelia in a continuous and stereotyped process called blastogenesis. Anatomy and ontogenies of blastogenesis are well described, however molecular signatures triggering this developmental process are entirely unknown. We isolated tissues at the site of blastogenesis onset and from the same epithelia where this process is never triggered. We linearly amplified an ultra-low amount of mRNA (<10ng) and generated three transcriptome datasets. To provide a conservative landscape of transcripts differentially expressed between blastogenic vs. non-blastogenic epithelia we compared three different mapping and analysis strategies with a de novo assembled transcriptome and partially assembled genome as references, additionally a self-mapping strategy on the dataset. A subset of differentially expressed genes were analyzed and validated by in situ hybridization. The comparison of different analyses allowed us to isolate stringent sets of target genes, including transcripts with potential involvement in the onset of a non-embryonic developmental pathway. The results provide a good entry point to approach regenerative event in a basal chordate.This work was supported by AFM Telethon grant (#16611), IRG Marie Curie grant (#276974), ANR (ANR-14-CE02-0019-01) and IDEX Super (INDIBIO). L.R. was supported by an UPMC-EMREGENCE grant and by a FRM grant (#FDT20140931163). A.C. was supported by a FRM grant (ING 20140129231)

    Comparative muscle development of scyphozoan jellyfish with simple and complex life cycles

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    International audienceBackground : Simple life cycles arise from complex life cycles when one or more developmental stages are lost. This raises a fundamental question - how can an intermediate stage, such as a larva, be removed, and development still produce a normal adult? To address this question, we examined the development in several species of pelagiid jellyfish. Most members of Pelagiidae have a complex life cycle with a sessile polyp that gives rise to ephyrae (juvenile medusae); but one species within Pelagiidae, Pelagia noctiluca, spends its whole life in the water column, developing from a larva directly into an ephyra. In many complex life cycles, adult features develop from cell populations that remain quiescent in larvae, and this is known as life cycle compartmentalization and may facilitate the evolution of direct life cycles. A second type of metamorphic processes, known as remodeling, occurs when adult features are formed through modification of already differentiated larval structures. We examined muscle morphology to determine which of these alternatives may be present in Pelagiidae.Results : We first examined the structure and development of polyp and ephyra musculature in Chrysaora quinquecirrha, a close relative of P. noctiluca with a complex life cycle. Using phallotoxin staining and confocal microscopy, we verified that polyps have four to six cord muscles that persist in strobilae and discovered that cord muscles is physically separated from ephyra muscle. When cord muscle is removed from ephyra segments, normal ephyra muscle still develops. This suggests that polyp cord muscle is not necessary for ephyra muscle formation. We also found no evidence of polyp-like muscle in P. noctiluca. In both species, we discovered that ephyra muscle arises de novo in a similar manner, regardless of the life cycle.Conclusions : The separate origins of polyp and ephyra muscle in C. quinquecirrha and the absence of polyp-like muscle in P. noctiluca suggest that polyp muscle is not remodeled to form ephyra muscle in Pelagiidae. Life cycle stages in Scyphozoa may instead be compartmentalized. Because polyp muscle is not directly remodeled, this may have facilitated the loss of the polyp stage in the evolution of P. noctiluca

    Instruments Measuring Self-Care in Children and Young Adults With Chronic Conditions: A Systematic Review

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    : Children and young adults (CYAs) with chronic conditions need to engage in self-care to improve their quality of life. This study aimed to retrieve the literature on instruments to assess self-care in CYAs living with chronic conditions and evaluate the psychometric proprieties of the instruments retrieved. A systematic literature review was conducted on six databases to identify peer-reviewed papers that described or used an evaluation instrument of self-care in CYAs with chronic conditions. Twenty-three articles describing 11 instruments of self-care were identified. Five instruments (45.45%) were developed for specific diseases, while six (54.54%) for various chronic illnesses. Most of the instruments were focused on treatment adherence within self-care maintenance (i.e., behaviors to maintain illness stability), excluding the monitoring of clinical parameters or the management of exacerbations. This review provides an overview of available instruments that measure self-care in CYAs with chronic conditions, which health professionals could use for patient education

    Hyaluronan uptake by adult human skin fibroblasts in vitro

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    Low and high molecular weight hyaluronan (HA) was added to adult human fibroblasts grown in monolayer to assess its influence on CD44 expression, its internalisation and effect on cell growth. CD44 expression on the surface of in vitro fibroblasts was not modified by different concentrations of FCS, whereas it was sensitive to cell cycle, being higher in the growing than in the resting phase. Independently from molecular weight, upon addition of exogenous HA (from 0.1 up to 1 mg/mL) to fibroblasts in the growing phase, a slight but constant decrease of the expression of CD44 on the surface of fibroblasts was observed; moreover, HA induced a rearrangement of CD44 into patches in close relationship with the terminal regions of stress fibers, which became thicker and more rigid after a few hours from the addition of HA to the medium. Fluorescent HA, added to the culture medium, rapidly attached to the plasma membrane and in less than two minutes was observed within cells, partly in association with its receptor CD44. By the contemporary use of neutral red, which accumulates into functional lysosomes, the great majority of internalised HA was found within lysosomes. HA receptor RHAMM-IHABP was rather homogeneously localised within the cytoplasm of normal growing fibroblasts. Upon addition of HA, the RHAMM-IHABP distribution became discontinuous around the nucleus. Addition of HA to fibroblasts induced a significant inhibition of cell growth, which was dependent on HA concentration and irrespective of HA molecular weight, at least in the ranges tested. Results show that extra-cellular HA is rapidly taken up by human dermal fibroblasts together with its CD44 receptor, and transported mostly to the lysosomes. Both low and high molecular weight HA induced down-regulation of cell proliferation, which would seem to be mediated by HA catabolism

    Pediatric nurses in pediatricians' offices: a survey for primary care pediatricians

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    Background: The role played by nurses in caring for children in pediatricians' officies in the community is crucial to ensure integrated care. In Italy, pediatricians are responsible for the health of children aged 0-14 years living in the community. This study aimed to describe Italian primary care pediatricians' opinions about the usefulness of several nursing activities that pediatric nurses could perform in pediatricians' offices. Methods: An online survey with pediatricians working in primary care in Italy was conducted between April-December 2018. A 40-item questionnaire was used to assess four types of nursing activities: clinical care, healthcare education, disease prevention, and organizational activities. The answers ranged from 1 (not useful at all) to 6 (very useful). Moreover, three open-ended questions completed the questionnaire. Results: Overall, 707 pediatricians completed the online survey. Participants were mainly female (63%), with a mean age of 57.74 (SD = 6.42). The presence of a pediatric nurse within the pediatrician's office was considered very useful, especially for healthcare education (Mean 4.90; SD 1.12) and disease prevention (Mean 4.82; SD 1.11). Multivariate analysis confirmed that pediatricians 'with less working experience', 'having their office in a small town', and 'collaborating with a secretary and other workers in the office' rated the nurse's activities significantly more useful. Conclusions: A pediatric nurse in the pediatrician's office can significantly contribute to many activities for children and their families in the community. These activities include clinical care, healthcare education, disease prevention, and the organizational processes of the office. Synergic professional activity between pediatricians and pediatric nurses could ensure higher health care standards in the primary care setting

    The current practice of family-centred care in Italian neonatal intensive care units: A multi-centre descriptive study

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    © 2018 Elsevier Ltd Objectives: To explore family-centred care practices in Italian neonatal intensive care units and describe areas for improvement. Methods: A cross-sectional, multicentre, survey was conducted using the Italian language version of “Advancing family-centred new-born intensive care: a self-assessment inventory”. The instrument is divided into 10 sections rating the status of family-centred care (1 = not at all, 5 = very well) and ranking the perceived priority for change/improvement (1 = low, 3 = high). A representative group of staff and parent for each unit were invited to complete the survey. Data was collected between January and June 2015. Correlations among unit characteristics and sections within the survey were explored. Settings: All Italian neonatal intensive care units (n = 105) were invited. Results: Forty-six (43.8%) units returned the survey. The “Leadership” section scored highest in status of family-centred care (mean = 3.45; SD 0.78) and scored highest in priority for change (mean = 2.44; SD 0.49). Section “Families as Advisors and Leaders” scored lowest both in status (mean = 1.66; SD 0.67) and in priority for change (mean = 2.09; SD 0.59). The number of discharged infants was positively correlated with many sections in priority for change (r 0.402–0.421; p &lt;.01). Conclusion: This study showed a variability in the organisation of family-centred care practices in Italian neonatal intensive care units and the need to involve parents as partners in the care team. Although family-centred care is considered important by Italian neonatology healthcare professionals, much remains to be done to improve family-centred care practices in neonatal intensive care units in Italy

    Measurement of the Branching Fraction for B- --> D0 K*-

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    We present a measurement of the branching fraction for the decay B- --> D0 K*- using a sample of approximately 86 million BBbar pairs collected by the BaBar detector from e+e- collisions near the Y(4S) resonance. The D0 is detected through its decays to K- pi+, K- pi+ pi0 and K- pi+ pi- pi+, and the K*- through its decay to K0S pi-. We measure the branching fraction to be B.F.(B- --> D0 K*-)= (6.3 +/- 0.7(stat.) +/- 0.5(syst.)) x 10^{-4}.Comment: 7 pages, 1 postscript figure, submitted to Phys. Rev. D (Rapid Communications
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