5,506 research outputs found
Effect of injection depth of digestate liquid fraction on soil carbon dioxide emission and maize biomass production
The aim of this study was to evaluate, in open field conditions, the effect of injection depth of digestate liquid fraction (10 cm, 25 cm and 35 cm) in clay loam soil, on CO2 emission. An un-amended soil was considered as control. The study was performed in 2014 on a farm located in Terrasa Padovana, Veneto region (Italy) distributing digestate before maize sowing. Digestate injection determined a high soil CO2 emission in the first
hour after application, followed by a progressive reduction in as early as 24 h, reaching significantly lower values, similar to those measured in the un-amended control, after 48 h. Gas emissions measured 1 h
after digestate application decreased as injection depth increased with significantly higher emission values in the 10 cm treatment (median value 23.7 g CO2 m\u20132 h\u20131) than in the 35 cm one (median value 2.5 g
CO2 m\u20132 h\u20131). In the 3 days between digestate distribution and maize sowing, soil CO2 emission was significantly higher in the amended treatments than un-amended one, with median values of 1.53 g CO2
m\u20132 h\u20131 and 0.46 g CO2 m\u20132 h\u20131 respectively. During maize growing season, no significant soil CO2 emission difference was monitored among treatments, with a median value of 0.33 g CO2 m\u20132 h\u20131. Digestate application significantly improved maize aboveground dry biomass with an average yield of 22.0 Mg ha\u20131 and 16.2 Mg ha\u20131 in amended and un-amended plots, respectively, due to the different amount of nutrients supplied
Dark Matter and IMF normalization in Virgo dwarf early-type galaxies
In this work we analyze the dark matter (DM) fraction, , and
mass-to-light ratio mismatch parameter, (computed with respect
to a Milky-Way-like IMF), for a sample of 39 dwarf early-type galaxies (dEs) in
the Virgo cluster. Both and are estimated within the
central (one effective radius) galaxy regions, with a Jeans dynamical analysis
that relies on galaxy velocity dispersions, structural parameters, and stellar
M/L ratios from the SMAKCED survey. In this first attempt to constrain,
simultaneously, the IMF normalization and the DM content, we explore the impact
of different assumptions on the DM model profile. On average, for a NFW
profile, the is consistent with a Chabrier-like normalization
(), with . One of the main results of
the present work is that for at least a few systems the is
heavier than the MW-like value (i.e. either top- or bottom-heavy). When
introducing tangential anisotropy, larger and smaller
are derived. Adopting a steeper concentration-mass relation than that from
simulations, we find lower () and larger . A
constant M/L profile with null gives the heaviest
(). In the MONDian framework, we find consistent results to those for
our reference NFW model. If confirmed, the large scatter of for
dEs would provide (further) evidence for a non-universal IMF in early-type
systems. On average, our reference estimates are consistent with those
found for low- () early-type
galaxies (ETGs). Furthermore, we find consistent with values from the
SMAKCED survey, and find a double-value behavior of with stellar mass,
which mirrors the trend of dynamical M/L and global star formation efficiency
with mass.Comment: 11 pages, 3 figures, 1 table, published on MNRAS. Figure 1 has been
updated with respect to version 1, including the range of values found if the
S\'ersic index, n, is varied from 0.5 to 2 (dark-green curves
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European local authorities’ financial resilience in the face of austerity: a comparison across Austria, Italy and England
European local authorities have been particularly stricken by the current context of decline and cutback management, and represent an ideal place where to study how governments respond to shocks affecting their financial conditions and management. Along these lines, this paper adopt the perspective of financial resilience for looking at the current context of austerity, and related responses, by shedding new lights on the role of internal capacities and conditions in influencing such responses and, ultimately, performance. Through a multiple case study analysis based on 12 European local authorities in Austria, Italy and England, the paper identifies the main shocks perceived by local management, the related short-term and long-term responses, highlighting the dynamics of financial vulnerabilty, awareness, anticipatory capacity, flexibility and recovery ability (ie, financial resilience) in its interaction with the external context and shocks. From the analysis, four patterns of resilience emerge: pro-active resilience, adaptive resilience, passive/fatalist resilience, complacent resilience
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Financial resilience in local authorities: an exploration of Anglo-Italian experiences
For more than thirty years public management and accounting theories and practice have been strongly influenced by the search for efficiency, heralded by the New Public Management and similar public sector modernization movements. Public administrations have focused their attention on economy, efficiency and effectiveness, looking for cost containment, matching resources and goals, output maximization or input minimization. Even the wave of development of performance measurement and management tools have mainly emphasized the importance of short-term efficiency, often without worrying too much about their ability to ensure public administrations’ responsiveness in the face of unexpected events and crises
Chemistry vs. Physics: A Comparison of How Biology Majors View Each Discipline
A student's beliefs about science and learning science may be more or less sophisticated depending on the specific science discipline. In this study, we used the physics and chemistry versions of the Colorado Learning Attitudes about Science Survey (CLASS) to measure student beliefs in the large, introductory physics and chemistry courses, respectively. We compare how biology majors -- generally required to take both of the courses -- view these two disciplines. We find that these students' beliefs are more sophisticated about physics (more like the experts in that discipline) than they are about chemistry. At the start of the term, the average % Overall Favorable score on the CLASS is 59% in physics and 53% in chemistry. The students' responses are statistically more expert-like in physics than in chemistry on 10 statements (P lesser-than-or-equal-to 0.01), indicating that these students think chemistry is more about memorizing disconnected pieces of information and sample problems, and has less to do with the real world. In addition, these students' view of chemistry degraded over the course of the term. Their favorable scores shifted -5.7% and -13.5% in 'Overall' and the 'Real World Connection' category, respectively; in the physics course, which used a variety of research-based teaching practices, these scores shifted 0.0% and +0.3%, respectively. The chemistry shifts are comparable to those previously observed in traditional introductory physics courses
Invariant NKT cells and rheumatic disease: Focus on primary sjogren syndrome
Primary Sjogren syndrome (pSS) is a complex autoimmune disease mainly affecting salivary and lacrimal glands. Several factors contribute to pSS pathogenesis; in particular, innate immunity seems to play a key role in disease etiology. Invariant natural killer (NK) T cells (iNKT) are a T-cell subset able to recognize glycolipid antigens. Their function remains unclear, but studies have pointed out their ability to modulate the immune system through the promotion of specific cytokine milieu. In this review, we discussed the possible role of iNKT in pSS development, as well as their implications as future markers of disease activity
Global Properties of the Rich Cluster ABCG 209 at z~0.2. Spectroscopic and Photometric Catalogue
This paper is aimed at giving an overview of the global properties of the
rich cluster of galaxies ABCG 209. This is achieved by complementing the
already available data with new medium resolution spectroscopy and NIR
photometry which allow us to i) analyse in detail the cluster dynamics,
distinguishing among galaxies belonging to different substructures and deriving
their individual velocity distributions, using a total sample of 148 galaxies
in the cluster region, of which 134 belonging to the cluster; ii) derive the
cluster NIR luminosity function; iii) study the Kormendy relation and the
photometric plane of cluster early-type galaxies (ETGs). Finally we provide an
extensive photometric (optical and NIR) and spectroscopic dataset for such a
complex system to be used in further analyses investigating the nature,
formation and evolution of rich clusters of galaxies. The observational
scenario confirms that ABCG 209 is presently undergoing strong dynamical
evolution with the merging of two or more subclumps. This interpretation is
also supported by the detection of a radio halo (Giovannini et al. 2006)
suggesting that there is a recent or ongoing merging. Cluster ETGs follow a
Kormendy relation whose slope is consistent with previous studies both at
optical and NIR wavelengths. We investigate the origin of the intrinsic scatter
of the photometric plane due to trends of stellar populations, using line
indices as indicators of age, metallicity and alpha/Fe enhancement. We find
that the chemical evolution of galaxies could be responsible for the intrinsic
dispersion of the Photometric Plane.Comment: 39 pages, 17 figures, MNRAS in pres
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