14,946 research outputs found
A linear filter to reconstruct the ISW effect from CMB and LSS observations
The extraction of a signal from some observational data sets that contain
different contaminant emissions, often at a greater level than the signal
itself, is a common problem in Astrophysics and Cosmology. The signal can be
recovered, for instance, using a simple Wiener filter. However, in certain
cases, additional information may also be available, such as a second
observation which correlates to a certain level with the sought signal. In
order to improve the quality of the reconstruction, it would be useful to
include as well this additional information. Under these circumstances, we have
constructed a linear filter, the linear covariance-based filter, that extracts
the signal from the data but takes also into account the correlation with the
second observation. To illustrate the performance of the method, we present a
simple application to reconstruct the so-called Integrated Sachs-Wolfe effect
from simulated observations of the Cosmic Microwave Background and of
catalogues of galaxies.Comment: 8 pages, 6 figures, accepted for publication in the IEEE Journal of
Selected Topics in Signal Processin
Estimation of dietary intake and content of lead and cadmium in infant cereals marketed in Spain
Lead and cadmium have become highly toxic metallic elements. There is an obvious
5 toxicological impact of these elements on infants since their intestinal absorption is
6 significantly higher than in adults, thus it is desirable to quantify lead and cadmium levels in
7 commonly consumed infant foods. Zeeman background correction, transversely heated
8 graphite furnace atomic absorption spectrometry, was used to determine both the lead and
9 cadmium content of 91 Spanish infant cereals. Cereals were assessed in terms of different
10 types, cereal predominant in formulation and whether it was obtained organically or
11 conventionally. Preliminary analysis revealed a noticeably higher content of lead and
12 cadmium (median, Q1-Q3) in organic cereals (n = 17, Pb: 26.07; 21.36-51.63; Cd: 18.52;
16.56-28.50 μg kg-1 13 ) in relation to conventional ones (n =74, Pb: 10.78; 6.43-19.33; Cd: 7.12;
4.40-11.77 μg kg-1 14 ). Three formulations exceeded European lead maximum levels. Added
15 ingredients (milk, cocoa, fruit and honey) to the cereal base provide lead enrichment. For
16 cadmium, this pattern was observed by cereal based on cocoa, but also the raw materials
17 contributed with a dilution phenomenon, decreasing the final cadmium concentration in infant
18 cereal. Apart from several organically produced cereals, lead content showed a narrow
19 variation, where gluten-free cereals provide lower cadmium content than formulations
20 containing gluten. Dietary intakes of both elements were assessed in comparison with the
21 reference intake values proposed by the EFSA Panel on Contaminants in the Food Chain.
22 Organic infant cereals based on honey and cocoa supplied the highest risk intakes of lead and
23 cadmium, respectively. In accordance with the actual state of knowledge on lead and
24 cadmium toxicity and attending to the upper limits calculated from risk intake values set by
25 EFSA, it seems prudent to call for a revision of both heavy metals content regulated by EC to
set a maximum guideline values for infant cereal at 55 and 45 μg kg-1 26 , respectively
Survey of total mercury and arsenic content in infant cereals marketed in Spain and estimated dietary intake.
Due to the fact that infants and children are especially sensitive to mercury and arsenic
7 exposure, predominantly through diet, a strict control of the most widely consumed
8 infant foods, especially infant cereals, is of paramount importance. Levels of both total
9 mercury and arsenic in 91 different infant cereals from ten different manufacturers in
10 Spain were determined by flow injection adapted to cold vapor and hydride generation
11 atomic absorption spectrometry, respectively. Cereals were assessed in terms of the
12 different types, the predominating cereal in the formulation, the added ingredients, and
13 whether the cereal was organically or conventionally obtained. In general, the content of
14 toxic elements (median (Q1;Q3)) found in infant cereals based on conventionally
obtained raw materials (n=74, Hg: 2.11 (0.42;4.58), As: 21.0 (9.4;50.9) μg·Kg-1 15 ) was
16 lower than in cereals produced by organic methods (n= 17, Hg: 5.48 (4.54;7.64), As:
96.3 (87.5;152.3) μg·Kg-1 17 ). Mercury content in infant cereals shows the higher values in
18 those formulations with ingredients susceptible to particulate contamination such as
19 gluten-free or cacao-based cereals. The highest arsenic content appears in the rice-based
20 cereals. The mercury and the inorganic arsenic dietary intakes for infants fed on the
21 infant cereals studied were assessed, taking into account the different stages of growth.
22 Organic infant cereals based on cocoa showed the highest risk intakes of mercury, very
23 close to exceeding the intake reference. Just the opposite, 95% of the organically
24 produced infant cereals and 70% of the conventional gluten-free infant cereals showed
25 an inadmissible risk of arsenic intake. Thus, it seems prudent to call for continued
26 efforts in standardizing routine quality control and in reducing arsenic levels in infant
27 cereals; in addition it is essential that relevant legislation be established and regulated
28 by EC regarding these two toxic elements
Surveillance of aflatoxin content in dairy cow feedstuff from Navarra (Spain)
Aflatoxins (B1, B2, G1 and G2) are produced by the fungi Aspergillus (A. flavus and A. parasiticus) in substrates used in cattle feed manufacturing. Aflatoxin M1 (AFM1) is a major metabolite of Aflatoxin B1 (AFB1) which may be present in milk from animals that consume contaminated feed. Levels of aflatoxins in 78 dairy cow feedstuff samples from 40 farms located in Navarra were determined by HPLC-FLD (High Performance Liquid Chromatography with fluorescence detection) and post-column derivatization. The influence of geographical location, season and type of feeding system on aflatoxin content was studied. The climatic profile of AFB1 pointed to spring as the season with the highest aflatoxin level (0.086 μg/kg), followed by winter and summer (0.075 and 0.030 μg/kg, respectively), and to a lesser degree, autumn (0.017 μg/kg). Moreover, wet and dry TMR (Total Mixed Ration) feeding systems (i.e. AFB1: 0.076 and 0.068 μg/kg; Aflatoxin G1 (AFG1): 0.050 and 0.011 μg/kg, respectively) showed a greater content of the analyzed aflatoxins in comparison with compound feed (i.e. AFB1: 0.039 μg/kg; AFG1: 0.007 μg/kg). The fact that the majority of the samples collected were based on compound feed shows that this type was preferred by most dairy farmers. The undetectable levels of aflatoxins in the organic homemade compound feedstuff are also worth mentioning. While none of the feedstuff samples contained amounts over those permitted under European legislation (5 μg/kg), the theoretical extrapolation of the carryover rate suggested in previously published experiments of AFB1 to AFM1 in secreted cow's milk predicts that only one of the feed samples studied had a positive aflatoxin level (53.4 ng/kg) higher than the legal limit for raw cow's milk
Effect of phytoremediated port sediment as an agricultural medium for pomegranate cultivation: Mobility of contaminants in the plant
Although the dredging of ports is a necessary management activity, it generates immense quantities of sediments, that are defined by the European Union as residues. On the other hand, the relevant peat demand for plant cultivation compromises its availability worldwide. In this context, the present work wanted to find an alternative substrate in order to replace and/or reduce the use of peat in agriculture, through the study of the suitability, concerning the exchange of substrate–plant–water pollutants, of the dredged remediated sediments as a fruit-growing media. Forty-five pomegranate trees (Punica granatum L. cv “Purple Queen”) were cultivated in three types of substrates (100% peat as a control, 100% dredged remediated sediments and 50% both mixed). The metal ion content and pesticide residues were analysed in the different plant parts (root, stem, leaves and fruits) and in drainage water. The results showed a limited transfer of pollutants. All the pollutants were below the legal limits, confirming that the dredged sediments could be used as a growing media, alone or mixed with other substrates. Thus, the results point out the need to open a European debate on the reuse and reconsideration of this residue from a circular economy point of view
Application of lca methodology to the production of strawberry on substrates with peat and sediments from ports
The Life Cycle Assessment (LCA) methodology was applied to identify the potential environmental impact of dredged sediments used as growing media for food crops. The dredged sediments used came from Livorno port and were previously phytoremediated. For the assay, strawberry plants (Fragaria x ananassa Duch vr. ‘San Andreas’) were used. The plants were cultivated on three different substrates (100% peat, 100% dredged sediment and 50% mix peat/sediment) to identify the real impact of the culture media on the growing process. LCA was calculated and analyzed according to ISO 14040:2006 by SimaPro software. ReCipe Midpoint (E) V1.13/Europe Recipe E method was applied. One kilogram of produced strawberry, for each crop media tested, was defined as the functional unit. Eighteen impact categories were selected where Marine Eutrophication (ME), Human Toxicity (HT) and Freshwater Ecotoxicity (FET) were identified as relevant impact categories. The LCA results showed an increase in the environmental impact of strawberry cultivation using 100% sediment against 100% peat, due to the decrease in fruit production caused by the sediment. Nevertheless, the decrease in the environmental impact and the fruit production increase identified when the sediment is used mixed (<50%) with other substrates. The appropriate use of these substrates would be justified within the context of the circular economy
Distribution of basement membrane antigens in glomeruli of mice with autoimmune glomerulonephritis.
peer reviewedGlomerulonephritis was induced in mice by the repeated injection of human glomeruli or purified glomerular basement membrane. The glomerular basement membranes of nephritic animals were observed to develop subepithelial extensions, "spikes." Although normally Type IV collagen is found throughout the full thickness of basement membranes, the "spikes" reacted with antibodies to laminin but not with antibodies to Type IV collagen. It is proposed that in murine autoimmune glomerulonephritis, the visceral epithelial cells produce an excess of laminin
Energy conversion theorems for some linear steady-states
One of the main issues that real energy converters present, when they produce
effective work, is the inevitable entropy production. Within the context of
Non-equilibrium Thermodynamics, entropy production tends to energetically
degrade man-made or living systems. On the other hand, it is also not useful to
think about designing an energy converter that works in the so-called minimum
entropy production regime since the effective power output and efficiency are
zero. In this manuscript, we establish some \textit{Energy Conversion Theorems}
similar to Prigogine's one with constrained forces, their purpose is to reveal
trade-offs between design and the so-called operation modes for
--linear isothermal energy converters. The objective
functions that give rise to those thermodynamic constraints show stability. A
two--meshes electric circuit was built as an example to demonstrate the
Theorems' validity. Likewise, we reveal a type of energetic hierarchy for power
output, efficiency and dissipation function when the circuit is tuned to any of
the operating regimes studied here: maximum power output (), maximum
efficient power (), maximum omega function (), maximum
ecological function (), maximum efficiency () and minimum
dissipation function ().Comment: 33 pages, 15 figures, 2 table
Comparison of central versus peripheral delivery of pregabalin in neuropathic pain states
<p>Abstract</p> <p>Background</p> <p>Although pregabalin therapy is beneficial for neuropathic pain (NeP) by targeting the CaVα<sub>2</sub>δ-1 subunit, its site of action is uncertain. Direct targeting of the central nervous system may be beneficial for the avoidance of systemic side effects.</p> <p>Results</p> <p>We used intranasal, intrathecal, and near-nerve chamber forms of delivery of varying concentrations of pregabalin or saline delivered over 14 days in rat models of experimental diabetic peripheral neuropathy and spinal nerve ligation. As well, radiolabelled pregabalin was administered to determine localization with different deliveries. We evaluated tactile allodynia and thermal hyperalgesia at multiple time points, and then analyzed harvested nervous system tissues for molecular and immunohistochemical changes in CaVα<sub>2</sub>δ-1 protein expression. Both intrathecal and intranasal pregabalin administration at high concentrations relieved NeP behaviors, while near-nerve pregabalin delivery had no effect. NeP was associated with upregulation of CACNA2D1 mRNA and CaVα<sub>2</sub>δ-1 protein within peripheral nerve, dorsal root ganglia (DRG), and dorsal spinal cord, but not brain. Pregabalin's effect was limited to suppression of CaVα<sub>2</sub>δ-1 protein (but not CACNA2D1 mRNA) expression at the spinal dorsal horn in neuropathic pain states. Dorsal root ligation prevented CaVα<sub>2</sub>δ-1 protein trafficking anterograde from the dorsal root ganglia to the dorsal horn after neuropathic pain initiation.</p> <p>Conclusions</p> <p>Either intranasal or intrathecal pregabalin relieves neuropathic pain behaviours, perhaps due to pregabalin's effect upon anterograde CaVα<sub>2</sub>δ-1 protein trafficking from the DRG to the dorsal horn. Intranasal delivery of agents such as pregabalin may be an attractive alternative to systemic therapy for management of neuropathic pain states.</p
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