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The assessment of radiological impact to the environment is usually carried out by the dose rate estimation to hypothetical entities named Reference Animals and Plants (RAPs). There are many codes to carry out this assessment, which requires the definition of a scenario and using site-specific transfer parameters when possible. Transfer parameters present a geographical bias, as they are mostly derived from temperate and arctic climate datasets, but there is a scarcity of data for Mediterranean climates. In this study, a terrestrial Mediterranean scenario was defined using the distribution of activity concentrations of anthropogenic ( 90 Sr, 137 Cs) and naturally occurring radionuclides ( 40  K, 210 Pb, 210 Po, 226,228 Ra, 235,238 U, 232 Th) in Cáceres province (Spain). Site-specific transfer factors, CR wo-media , defined as the ratio between the concentration in the whole organism and the medium (soil in this case) were considered. Dose rate assessments for terrestrial RAPs were carried out using Tier 3 in ERICA Tool, ranging 0.23-3.73 µGy/h which is below the screening level of 10 µGy/h. Therefore, no harmful effects are expected to occur. Internal dose rate predominates over external one because the main contributors are naturally occurring radionuclides (in most cases 40  K, 226,228 Ra, 210 Pb, 210 Po), which are mostly α-emitting radionuclides. These results can be used for the evaluation of other radiological and nuclear installations in Mediterranean climates, as they set the background dose rate., (© 2024. The Author(s).)

The radionuclide concentration of man-made radionuclides on non-human biota in freshwater ecosystems has been extensively studied in environments affected by the Chernobyl and Fukushima accidents, in both humid continental and subtropical climates, respectively. However, there are very few studies that assess the long-term effects of operating nuclear facilities in Mediterranean environments. In the present study, a temporal analysis of the impact on carp, cattail, and bulrushes in the cooling pond of the currently operating Almaraz nuclear power plant was investigated for the period 2000-2020. The results do not show a general trend in man-made radionuclide concentrations. Instead, depending on their availability and the type of organism, trends decrease over time. This is also reflected in the effective half-lives obtained, which are lower than the physical half-life for some radionuclides. Transfer coefficients for the main man-made radionuclides detected were obtained, and it was found that these were significantly lower than the typical ranges found for benthic fish and vascular plants in freshwater ecosystems. Finally, the internal and external doses received by the carp have been evaluated using ERICA tool, and it has been observed that the main contribution to the total dose is due to the internal dose (0.65-7.04) × 10 -4  µGy/h., (© 2024. The Author(s).)

In many small communities in the Mediterranean area, groundwater is usually the only water body available. Depending mainly on the surrounding geology, their concentration of naturally occurring radionuclides may pose a radiological hazard. Removal of uranium and radium from drinking water is the best way to avoid it, i.e., reverse osmosis (RO), but consuming a lot of energy. Thus, two modified drinking water treatment plants (DWTPs) using zeolites coated with manganese dioxide as adsorbent material were analyzed as an alternative to RO. Groundwater salinity can negatively affect this process. Radium removal decreased as water salinity increased; but it had a major impact on uranium, rendering the adsorption effectless in one DWTP. Waste management and how to avoid it from becoming radioactive are of major concern. Radium and uranium were associated to the reducible fraction in the filter material and also to the carbonate fraction in the case of uranium. Regeneration of the filter material using KCl solutions was able to remove 81% and 63% of uranium and radium, respectively., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Worldwide, dairy sector consumes 19% of the water in the livestock sector. However, in Latin America, the amount of water used in this sector is unknown, especially in arid zones. On the other hand, water footprint (WF) is a methodology to estimate the use of water to produce a product. The aim of this work was to estimate the WF of dairy production in the arid zone of the Peruvian central coast. Data from five dairy farms were used. The WF was calculated in its three dimensions: green water, blue water and grey water. In addition, the WF was measured for categories: feed, drinking and service. To measure the WF of feed production, the CROPWAT software was used, whilst the NRC (2001) equations were used to estimate the drinking water. The reference unit was cubic metres per kilogram of fat and protein corrected milk (FPCM). In average, 99% of the WF comes from feed production, followed by drinking water (0.4%). From the three dimensions of the WF, green water is responsible of 60% of the WF, followed by the blue water (30%). Imported water represented 63% of the WF. In general, WF of dairy production in these systems was 0.66 m 3 /kg FPCM. In conclusion, feed production, as the main source of WF from which most is imported, shows the possibility of reducing the WF of these systems by prioritizing and optimizing water consumption by crops using local resources with lower water requirements., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Sheep milk production is incipient in Mexico with scarce knowledge on the performance of dairy ewes from different breeds. The objective of this study was to evaluate the effect of breed (Awassi (Aw), East Friesian (EF) and other (Ot)), parity number (1, 2 and 3 or more (+ 3)), litter size (1 and 2 or more (+ 2)) and lambing season (spring-summer (SS) and autumn-winter (AW)) on day of peak yield (DP), peak yield (PY), persistency (P), total milk yield (TMY), 305-day milk yield (TMY305d), 150-day milk yield (TMY150d) and lactation length (LL) of crossbred dairy ewes in a flock of the central highlands of Mexico. A total of 4312 weekly milk yield records collected from 2014 to 2015 were used to model 133 lactations using a random regression model with a fifth-order orthogonal polynomial. Flock mean values of curve parameters were 42 days at DP, 1.2 kg/day at PY, - 3.5 g/day of P, 190 kg TMY, 189 kg TMY305, 124 kg TMY150 and 269 days of LL. Multiparous ewes had significantly higher (P < 0.05) PY and TMY than primiparous ewes. Ewes that lambed in AW had 15% higher PY and produced 14% more TMY than ewes that lambed in SS (P < 0.05). Correlations among curve parameters were significant except for the correlation between PY and LL and between P and TMY150d. TMY was strongly correlated with LL (0.91). Predominantly Awassi crossbred ewes had lower curve parameter values than predominantly East Friesian and other crossbred ewes., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Maize silage is appreciated for dairy cows due to its high energy content. Mexico is a centre of origin for maize and small-scale dairy farmers use landrace 'criollo' maize silages to feed their herds. However, the characteristics of landrace 'criollo' maize silages in terms of starch content, which defines their nutritional value in terms of energy, are not known. The objective was to characterise criollo maize silages in terms of starch content. Seventy-seven silage samples from 2011 to 2015 were analysed for contents of dry matter (DM), organic matter (OM), neutral detergent fibre (NDF), acid detergent fibre (ADF), crude protein (CP), in vitro dry matter digestibility (IVDMD), and starch content. A factor analysis using principal component analysis as an extraction method was undertaken, and a hierarchical cluster analysis performed. Five factors affected the starch content of silages and five maize silage clusters identified. There was a positive association between IVDMD and metabolisable energy and between crude protein and acid detergent fibre; moreover, a positive relation was found between dry matter and maize starch contents. Significant differences were found (P < 0.001) for the contents of IVDMD, ME, ashes, OM, DM, and starch. The DM content of group 1 silage did not show any significant differences from other groups, except with group 2 silage, which had the lowest contents of DM and starch. Therefore, group 1 and 5 silage had the highest DM and starch contents, while group 3 silage had the highest IVDMD values and ME contents; finally, group 4 had the highest ash contents. Starch content in criollo maize silages was higher that reports for other maize races and is influenced by climate conditions and dry matter content., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

The objective of this study was to estimate the carbon footprint (CF) of milk production (in kg of CO 2 equivalents (CO 2 e) per kg of fat and protein corrected milk (FPCM)) in dairy farms of the San Martín region, in the Peruvian Amazon. A cradle-to-farm gate characterization and analysis were carried out on eight representative dairy farms. Greenhouse gas (GHG) emissions were estimated using equations, following the 2019 refinement of the 2006 IPCC Guidelines. The results showed an average milk production of 9.7 ± 0.82 L milk/cow/day, Gyr x Holstein crosses as the predominant breed, use of cultivated grasses such as Brachiaria brizantha, living fences (Guazuma ulmifolia Lam) as the predominant silvopastoral arrangement, and low level of external inputs such as feed or grain additives. In relation to CF, an average value of 2.26 ± 0.49 kg CO 2 e/kg FPCM was obtained, with enteric fermentation being the most important source (1.81 ± 0.51 kg CO 2 e/kg FPCM), followed by manure management, land use, and energy/transport (0.26 ± 0.06, 0.14 ± 0.04, and 0.05 ± 0.04 kg CO 2 e/kg FPCM, respectively). Differences were found between farmers, obtaining lower CF values (1.76 vs 3.09 kg CO 2 e/kg FPCM) on farms with better feed quality, higher production levels, and a higher percentage of lactating animals compared to dry cows. It is concluded that dairy farms in the Peruvian Amazon region can reduce their emissions if they improve their current feeding practices., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

The study reviewed carbon footprint (CF) analyses for milk production in Latin America from cradle to farm gate. The objective was to estimate (1) the effect of feeding management (zero-grazing, semi-confinement, and pasture), (2) cattle system (specialized dairy vs. dual-purpose), and (3) region (tropical vs. temperate) on milk production (kg/cow/day) and CF (kg CO 2 eq/kg fat and protein corrected milk (FPCM)). A systematic literature review was conducted, and for the final analysis, a total of 32 individual CF (from 11 studies) were used. Studies included in the final analysis allowed to calculate CF per kg FPCM, included upstream emissions calculations, and used the IPCC's tier 2 approach for enteric methane emissions. The range of the CF observed in the region was from 1.54 to 3.57 kg CO2eq/kg FPCM. Feeding management had a significant effect on milk production, but not on CF. Zero-grazing compared with pasture systems had a 140% greater milk production (20.1 vs. 8.4 kg milk/cow/day), but numerically greater CF for pasture systems (2.6 vs. 1.7 kg CO 2 eq/kg FPCM). Compared with specialized dairy cattle, dual-purpose cattle produced less milk (P < 0.001) and higher CF (P < 0.05). Compared with temperate regions, tropical region systems produced less milk and higher CF. In conclusion, in Latin America, the cattle system and region have a significant impact on CF, whereas the feeding management (zero-grazing, semi-confinement, and pasture) does not impact the CF of milk produced., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Small-scale dairy systems (SSDS) are important source of livelihood and socio-economic wellbeing for the rearers in general. The reduction of methane emissions with the inclusion of sunflower seed or seed-meal in rations for dairy cows has been reported in several studies. However, studies pertaining to the use of sunflower silage in dairy cattle feeding are lacking. The present study was conducted to assess the productive, economic, and environmental effects of the inclusion of graded levels of sunflower silage at 0%, 20%, 40%, and 60% (SFSL) along with maize silage (MZSL) on a dry matter basis. The silage was provided to eight Holstein cows in two 4×4 Latin-squares with 14-day periods. The study encompassed the productive performance of the cows, composition of feeds, besides the feeding costs, and enteric methane emissions estimated. The study indicated that inclusion of SFSL in the diet enhanced (P<0.001) the FCM by 3.5% and milk-fat content. SFSL increased feeding costs, but income/feeding costs ratios did not differ across the treatments. The higher inclusion of SFSL reduced methane emissions/kg of DM intake, / kg of milk, and in energy lost as methane. The inclusion of sunflower silage in feeding strategies for cows may be a viable alternative by increasing their milk yields and milk fat content and reducing methane emissions without affecting the income/feeding costs ratios.

In Mexico little is known about high-altitude glacial psychrotolerant or psychrophilic fungal species, with most glacial fungi isolated from polar environments or Alpine glaciers. It has been documented that some of these species may play an important role in bioremediation of contaminated environments with heavy metals. In the present study, 75 fungi were isolated from glaciers in Citlaltépetl (5675 masl) and Iztaccíhuatl (5286 masl) volcanoes. Combining morphological characteristics and molecular methods, based on ITS rDNA, 38 fungi were partially identified to genus level, 35 belonging to Ascomycota and three to Mucoromycota. The most abundant genera were Cladosporium, followed by Alternaria and Sordariomycetes order. All isolated fungi were psychrotolerant, pigmented and resistant to different concentrations of Cr(III) and Pb(II), while none tolerated Hg(II). Fungi most tolerant to Cr(III) and Pb(II) belong to the genera Stemphylium, Cladosporium and Penicillium and to a lesser extent Aureobasidium and Sordariomycetes. To our knowledge, this is the first report on cultivable mycobiota richness and their Cr and Pb tolerance. The results open new research possibilities about fungal diversity and heavy metals myco-remediation. Extremophilic fungal communities should be further investigated before global warming causes permanent changes and we miss the opportunity to describe these sites in Mexico.

Knowledge of soil-to-plant transfer processes is a key element that can have a significant health impact. Much effort has been taken to characterize the speciation of anthropogenic radionuclides released into the environment. However, the information about naturally occurring radionuclides is scarce. This work evaluate the potential risks of transference, that is, the bioavailability of the 234,238 U, 226 Ra, 228,230,232 Th, and 210 Po in three different soils collected in Mediterranean ecosystems. Chemical speciation of these radionuclides was carried out according to two different methods, Pavlotskaya and a modification of Tessier's protocol. Most of these radionuclides were associated to fractions strongly bound to soil particles and not able to be transferred. Increasing concentrations of U and Th extracted with increasing volume of NH 4 OAc 1 M were observed, until it reached saturation. Readily bioavailable fraction in both methods (either exchangeable or water soluble + exchangeable) decreased in the following order: 226 Ra >  234,238  U >  228,230,232 Th >  210 Po. It was found that < 3% of the natural radionuclide concentration in soil are readily bioavailable for plant uptake in this region of Spain, and the resulting human health risk is negligible from natural radionuclide ingestion.

Inorganic fertilizers are used as agricultural countermeasures intended to inhibit the soil to plant transfer of radionuclides after a radioactive fallout. Two NH 4 + fertilizers, diammonium phosphate (DAP) and NPK, were applied to soil contaminated with a mixture of radionuclides to analyze whether they modify the transfer of 137 Cs, 90 Sr, and 60 Co and stable elements (K, Na, Ca, and Mg) to wheat plantlets grown under controlled laboratory conditions. DAP introduced NH 4 + in the soil, which can increase 137 Cs transfer, while NPK also introduced K + , which can decrease it. The application of DAP increased the accumulation of 137 Cs in wheat plantlets with increasing application rate, so did the 137 Cs/K in plantlets. Regarding the NPK application, the 137 Cs increased in all treatments, but at maximum rate, the available K introduced by the fertilizer was probably able to partially satisfy the nutritional requirements of the wheat plantlet and the 137 Cs decreased relative to the recommended rate. The 137 Cs/K ratio in plantlet decreased with increasing NPK rates. The transfer of 90 Sr increased with increasing DAP rate and only at the maximum NPK rate. The 60 Co transfer only increased at the maximum application rates for DAP and NPK. These modifications should be considered when using these fertilizers as agricultural countermeasures.

Although the pathogenesis of ischemia reperfusion (IR) injury is based on complex mechanisms, free radicals play a central role. We evaluated membrane fluidity and lipid peroxidation during pancreas transplantation (PT) performed in 12 pigs (six donors and six recipients). Fluidity was measured by fluorescence spectroscopy, and malondialdehyde (MDA) and 4-hydroxyalkenals (4-HDA) concentrations were used as an index of lipid oxidation. Pancreatic tissues were collected as follows: (A) donor, immediately before vascular clamping; (B) graft, following perfusion lavage with University of Wisconsin preservation fluid; (C) graft, after 16 h of cold ischemia; and (D) recipient, 30 min vascular postreperfusion. Fluidity and MDA and 4-HDA concentrations were similar in cases A, B, and C. However, there was significant membrane rigidity and increased lipid peroxidation after reperfusion (D). These findings suggest that reperfusion exaggerates oxidative damage and may account for the rigidity in the membranes of allografts during PT.

Organic dyes have great potential for its use in solar cells. In this recent work, the molecular structure and properties of Dye 7 were obtained using density functional theory (DFT) and different levels of calculation. Upon comparing the molecular structure and the ultraviolet visible spectrum with experimental data reported in the literature, it was found that the M05-2X/6-31G(d) level of calculation gave the best approximation. Once the appropriate methodology had been obtained, the molecule was characterized by obtaining the infrared spectrum, dipole moment, total energy, isotropic polarizability, molecular orbital energies, free energy of solvation in different solvents, and the chemical reactivity sites using the condensed Fukui functions.

Background: Treatment with GH promotes linear growth and decreases body fat in patients with isolated GH deficiency (GHD). However, few studies have analyzed how GH replacement modifies ghrelin levels and the adipokine profile and the relationship of these modifications with the metabolic changes., Aims: To analyze the eventual differences between serum levels of leptin, leptin soluble receptor (sOBR), resistin, adiponectin, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), total (TG) and acylated ghrelin (AG) and lipid and glycemic profiles in children with GHD, as well as to determine the effect of GH replacement on these parameters during the first year of therapy., Subjects and Methods: Thirty pre-pubertal (Tanner stage I) GHD children and 30 matched controls were enrolled. Children with GHD were studied before and after 6 and 12 months of GH treatment. Weight, height, BMI, fasting glucose, insulin, lipid profile and serum levels of adipokines and ghrelin were studied at every visit. Adi - pokines, insulin and ghrelin levels were determined by using commercial radio- and enzymoimmunoassays., Results: At baseline children with GHD had significantly higher sOBR (p<0.01) and adiponectin (p<0.01) levels than controls. Treatment with GH resulted in a decline in leptin (p<0.05) and TG (p<0.001) levels, an increase of homeostasis model assessment index and restored IGF-I levels (p<0.001)., Conclusions: These data indicate that GH replacement has a negative effect on leptin levels and may also produce a slight unfavorable effect on carbohydrate metabolism. In addition, the changes observed in the adipokine profile appear to be independent of body mass index.

South American siskin radiation was studied by both mitochondrial cytochrome b (mt cyt b) DNA sequencing and homologous phenotypic characters; the latter were coded separately according to sex. Mixed phenetic and molecular (total evidence) dendrograms were constructed and the corresponding analyses suggest that speciation started in the South American siskin group with a north to south separation (Carduelis notata/C. barbata) along the Andean spine. A second split may have taken place around the Peruvian Andean mountains, corresponding to the present distribution pattern of C. olivacea. The most recent speciation events seem to have occurred in three sister species pairs: (i) C. xanthogastra/C. atrata, (ii) C. magellanica/C. yarrellii, (iii) C. cucullata/C. crassirostris. Accumulation of consistent characters in both morphological and molecular data at the basal nodes of the dendrograms indicate that speciation events occurred within a short period of time. Our data also suggest that speciation probably occurred by sexual selection through female mating choice in this radiation. Additionally, studies of variable amino acid residues in the mt cyt b molecule show that the three variable amino acids found are placed in the mitochondrial transmembrane region, which is also part of the hypervariable region in mammals. Each of the three amino acid changes occur in each of the three postulated evolutionary groups.

Mitochondrial cytochrome b (cyt b) from 24 Carduelini species including crossbills, bullfinches, grosbeaks, rosefinches, and other related, but not conclusively classified species, was sequenced. These sequences were also compared with all the available sequences from the genera Carduelis, Serinus, and Passer. Phylogenetic analyses consistently gave the same groups of finches and the calculated divergence times suggest that speciation of the studied species occurred between 14 and 3 million years ago (Miocene-Pliocene), appearing before the Passer, Carduelis, and Serinus genera. Pleistocene glaciations may have been important in sub-speciation. Crossbills are integrated within the genus Carduelis, and within redpolls; the common crossbill shows subspeciation with Loxia japonica in the Pleistocene epoch. Pinicola enucleator groups together with bullfinches and is probably the ancestor of the group. Hawfinch is only distantly related to the studied groups, and might either represent an isolated genus or be related to the New World genus Hesperiphona. The grosbeak genera Eophona and Mycerobas are clearly sister groups, and species belonging to the former might have given rise to Mycerobas species. The isolated (in classification) Uragus sibiricus and Haematospiza sipahi are included within the genus Carpodacus (rosefinches); Carpodacus nipalensis is outside the genus Carpodacus in the molecular analyses and might be an isolated species or related to the genus Montifringilla.