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1.
J Dairy Sci ; 107(1): 169-183, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37690729

ABSTRACT

Our objectives were to determine the effect of fat (skim to whole milk) and protein (3.4%-10.5%) concentration on the sensory and physical properties of milk beverage base that had lactose and other low molecular components removed by ultrafiltration (UF). In experiment 1, a matrix of 16 treatments was produced to achieve 4 levels of lactose removal (0%, 30%, 70%, and 97%) at each of 4 fat levels (skim, 1%, 2%, and whole milk). In experiment 2, a matrix of 12 treatments was produced to achieve 4 levels of lactose removal (0%, 30%, 70%, and 97%) at each of 3 protein concentrations (3.4%, 6.5%, and 10.5% protein). Physical and sensory properties of these products were determined. Removal of >95% of milk lactose by UF required a diafiltration volume of approximately 3 times the milk volume. Lactose and low molecular weight solute removal increased whiteness across the range from skim to whole milk while decreasing viscosity and making milk flavor blander. In addition, lactose (and other low molecular weight solute) removal by UF decreased titratable acidity by more than 50% and increased milk pH at 20°C to >7.0. Future work on milk and milk-based beverages with lactose removed by UF needs to focus on interaction of the remaining milk solids with added flavorings, changing casein to whey protein ratio before removal of lactose by UF, and the effect of lactose and low molecular weight solute removal on heat stability, particularly for neutral-pH, shelf-stable milk-based beverages.


Subject(s)
Milk , Ultrafiltration , Animals , Ultrafiltration/veterinary , Milk/chemistry , Lactose/analysis , Caseins/analysis , Whey Proteins/analysis , Milk Proteins/analysis , Food Handling , Hydrogen-Ion Concentration
2.
Trop Anim Health Prod ; 53(4): 445, 2021 Aug 24.
Article in English | MEDLINE | ID: mdl-34427775

ABSTRACT

To assess the effect of hair type on the heat stress response, 20 Criollo Limonero heifers with slick (n = 11) or normal hair (n = 9) were studied. Under a high temperature-humidity index (THI) environment, heat stress response was assessed through physiological variables that included respiration rate (RR), heart rate (HR), ruminal frequency (RMF), rectal temperature (RT), saliva pH (SPH), and lymphocyte count (LC) in the morning (5:00 AM, 27.4 °C, 64% relative humidity, THI = 77) and afternoon (1:00 PM, 34.5 °C, 70% relative humidity, THI = 88). A case-control study using a split plot design was used. Data were analyzed using ANOVA (PROC MIXED SAS 2010) and a statistical model comprising the fixed effects of hair length, sampling hour, interaction of hair length by sampling hour, and the random effect of animal nested within hair type on physiological variables associated with heat stress response. Sampling hour influenced (P < 0.0001) RR, RT, and (P < 0.003) SPH. Hair length influenced RR (P < 0.01) and RT (P < 0.04) and tended to influence LC (P < 0.07). The interaction of sampling hour by hair influenced RR (P < 0.04), RT (P < 0.0002), and both SPH and LC (P < 0.05). During afternoon hours, slick-haired heifers had lower values for RR (81 ± 4.2 vs 102 ± 4.7 bpm; P < 0.01), RT (39.5 ± 0.1 vs 40.3 ± 0.1 C°; P < 0.002), and LC (60 ± 3.2 vs 72.3 ± 3.6; P < 0.09) than normal-haired heifers. In normal-haired heifers, SPH increased during afternoon compared to morning-hours (8.66 ± 0.1 vs 9.11 ± 0.1; P < 0.04). It was concluded that slick-coated heifers exhibited an enhanced capability to cope with heat stress compared to normal-haired heifers likely due to an enhanced capacity for heat dissipation.


Subject(s)
Cattle Diseases , Heat Stress Disorders , Animals , Body Temperature Regulation , Case-Control Studies , Cattle , Female , Heat Stress Disorders/veterinary , Heat-Shock Response , Humidity
3.
Fish Shellfish Immunol ; 95: 564-573, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31706009

ABSTRACT

Soybean meal is one of the most promising alternatives to replace fishmeal in the aquaculture industry. However, its ingestion triggers an intestinal inflammatory process that compromises fish health and nutrition. Therefore, finding strategies that reduce the deleterious effects of a soy protein-based diet are relevant. In this work we analyzed the effects of an aloe vera (Aloe barbadensis miller, AV) extract on intestinal inflammation and innate immunity of zebrafish by adding it to the water and by supplementing it in a soybean meal-based diet. To search for potential immunomodulatory effects of AV, we tested its effectiveness in two inflammation assays and compared fish fed with either fishmeal or soybean meal-based feed supplemented with AV. Our results show a strong anti-inflammatory effect of AV. Furthermore, while soy-based meal strongly induces the expression of inflammation markers, supplementation with AV reverted this effect. Finally, we show that fish fed with a soy meal diet are highly susceptible to bacterial infection, but that this condition is significantly reduced when the soy meal is supplemented with AV. Our results suggest that AV is a good candidate to be incorporated as an additive in farmed fish diets to facilitate the replacement of fishmeal by soybean meal, maintaining intestinal health.


Subject(s)
Aloe/chemistry , Anti-Inflammatory Agents/therapeutic use , Inflammation/therapy , Intestines/immunology , Plant Extracts/therapeutic use , Soybean Proteins/adverse effects , Zebrafish/immunology , Animal Feed , Animals , Aquaculture , Dietary Supplements/analysis , Intestines/drug effects , Soybean Proteins/administration & dosage
4.
Appl Radiat Isot ; 127: 103-108, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28551490

ABSTRACT

Zinc borate, Zn(BO2)2, doped with different concentrations of terbium (0.5-8mol%) was synthesized and polycrystalline samples were characterized by Scanning Electron Microscopy and X-Ray Diffraction. The Zn(BO2)2 was formed in the pure samples sintered at 750 and 800°C which has the body centered cubic structure, and a ZnB4O7 primitive orthorhombic phase was present. The thermoluminescent intensity was dependents on the thermal treatment (250-500°C) and also on the impurity concentration. The linear dose-response was obtained between 0.022-27.7Gy and 0.5-50Gy when the samples were exposed to beta and gamma radiation, respectively. The complex structure of the glow curves was analyzed by the Computerized Glow Curve Deconvolution method. The kinetics parameters were calculated assuming the general order kinetics model describing accurately the TL process. The glow curves of Tb3+-doped zinc borate phosphor were well deconvolved by six glow peaks. Zinc borate with 8mol% of impurity concentration exhibited an intense radioluminescent emission. The radioluminescent spectra show their maximum bands at 370, 490, 545 and 700nm related to the terbium ion in the zinc borate. These obtained results suggest that the terbium doped zinc borate is a promising phosphor for use in radiation dosimetry because of its high TL sensitivity to the ionizing radiation.

5.
Scand J Med Sci Sports ; 24 Suppl 1: 57-65, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24944132

ABSTRACT

We evaluated the effects of recreational football training combined with calorie-restricted diet (football + diet) vs calorie-restricted diet alone (diet) on aerobic fitness, lipid profile, and insulin resistance indicators in type 2 diabetes (T2D) patients. Forty-four T2D patients aged 48-68 years (27 females, 17 males) were randomly allocated to the football + diet group (FDG; n = 22) or to the diet group (DG; n = 22), of whom 19 FDG and 15 DG subjects completed the study. The football training was performed for 3 × 40 min/week for 12 weeks. Dual-energy X-ray absorptiometry scanning, treadmill testing, and fasting blood samplings were performed pre and post-intervention. After 12 weeks, maximal oxygen uptake (VO2max ) was elevated (P < 0.05) by 10 ± 4% in FDG but not in DG (-3 ± 4%, P < 0.05). After 12 weeks, reductions in blood triglycerides (0.4 ± 0.1 mmol/L), total cholesterol (0.6 ± 0.2 mmol/L), low-density lipoprotein, and very low-density lipoprotein levels were observed only in FDG. Fat mass decreased (P < 0.05) by 3.4 ± 0.4 kg in FDG and 3.7 ± 0.4 kg in DG. The lower (P < 0.05) glucagon and homeostatic model assessment of insulin resistance indicated an improvement in insulin sensitivity in FDG. In conclusion, football combined with restricted diet was effective in enhancing VO2max , reducing total cholesterol and triglycerides, and increasing insulin sensitivity, potentially providing better tools for the prevention of T2D complications than diet alone.


Subject(s)
Cholesterol/blood , Diabetes Mellitus, Type 2/therapy , Exercise Therapy/methods , Insulin Resistance , Physical Fitness , Soccer/physiology , Triglycerides/blood , Aged , Biomarkers/blood , Blood Glucose/metabolism , Brazil , Caloric Restriction , Combined Modality Therapy , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/physiopathology , Female , Heart Rate , Humans , Male , Middle Aged , Oxygen Consumption , Treatment Outcome
6.
J Environ Manage ; 143: 197-207, 2014 Oct 01.
Article in English | MEDLINE | ID: mdl-24912107

ABSTRACT

In the central part of the Iberian Peninsula there are old sealed landfills containing soils co-contaminated by several heavy metals (Cu, Zn, Pb, Cd, Ni, As, Cr, Fe, Al, Mn) and organic pollutants of different families (hydrocarbons, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, pesticides and other organochlorinated compounds, phenols and volatile compounds), which this work will address. We have focused on phytoremedial plants that are able to deal with this type of complex pollution, not only species that tolerate the joint effect of heavy metals in the soil, but also those that can take advantage of associated bacteria to efficiently break down organic compounds. This study was carried out with Lupinus luteus and its endophytes in two greenhouse experiments: A) growing in a substrate artificially contaminated with benzo(a)pyrene (BaP), and B) using real co-contaminated landfill soils. Endophytes of roots and shoots were isolated in both bioassays. Plant growth-promotion tests and organic pollutant tolerance and degradation tests were conducted on all strains isolated in bioassay A), and on those proving to be pure cultures from bioassay B). The selected landfill is described as are isolation and test procedures. Results indicate that plants did not show toxicity symptoms when exposed to BaP but did when grown in landfill soil. Some endophytes demonstrated plant growth-promotion capacity and tolerance to BaP and other organic compounds (diesel and PCB commercial mixtures). A few strains may even have the capacity to metabolize those organic pollutants. The overall decline in plant growth-promotion capacity in those strains isolated from the landfill soil experiment, compared with those from the bioassay with BaP, may indicate that lupin endophytes are not adapted to metal concentration in roots and shoots and fail to grow. As a result, most isolated root endophytes must have colonized root tissues from the soil. While preliminary degradation tests showed promising results (some strains exhibiting the potential to use organic pollutants as their sole source of carbon), these are not conclusive and further in-depth degradation assays need to be performed.


Subject(s)
Biodegradation, Environmental , Endophytes , Lupinus/metabolism , Metals, Heavy/metabolism , Plant Roots/microbiology , Soil Pollutants/analysis , Bacteria/metabolism , Benzo(a)pyrene/pharmacokinetics , Benzo(a)pyrene/toxicity , Biological Assay , Carbon/metabolism , Hydrocarbons/analysis , Hydrocarbons/pharmacokinetics , Lupinus/drug effects , Lupinus/growth & development , Metals, Heavy/analysis , Plant Roots/metabolism , Polychlorinated Biphenyls/analysis , Polychlorinated Biphenyls/pharmacokinetics , Polycyclic Aromatic Hydrocarbons/analysis , Polycyclic Aromatic Hydrocarbons/pharmacokinetics , Soil , Soil Microbiology , Soil Pollutants/pharmacokinetics , Spain , Waste Disposal Facilities
7.
Theriogenology ; 79(7): 1041-4, 2013 Apr 15.
Article in English | MEDLINE | ID: mdl-23465721

ABSTRACT

The objective was to assess the effect of biostimulation by the male presence and social organization on the interval from calving to resumption of ovarian cyclicity (ICR). Thirty Angus cows were allocated according parity into three groups (10 per group); two groups were exposed to bulls, and a third group not exposed to bulls served as a control. Dominance values (with subsequent arc-sin transformation) were calculated from daily recorded agonistic interactions and later organized into dominance order comprising three social categories as follows: dominant (D), intermediate (I), and subordinates (S). The ICR was established by determining presence of luteal tissue and a rise of blood progesterone concentration above 1 ng/mL using ultrasonography and a solid-phase, nonextraction radioimmunoassay (Coat-a-Count; Diagnostics Products Corporation, Los Angeles, CA, USA), respectively. The effect of biostimulation, dominance order, and treatment by dominance order on ICR was statistically analyzed applying ANOVA using PROC GLM of SAS (2010). The ICR was influenced by biostimulation (P < 0.002) and dominance order (P < 0.004). The ICR increased as dominance order decreased (D = 34.5 ± 6 days; I = 45.0 ± 6; S = 53.1 ± 4 days; P < 0.01). However, when comparing cows within social categories, ICR was reduced in the group exposed to bulls (D = 26.3 ± 8.2 days; I = 42.0 ± 6.4 days; S = 46.1 ± 4.1 days) compared with those not exposed to bulls (D = 43.0 ± 8.2 days; I = 48.0 ± 10.1 days; S = 60.2 ± 6.4 days) cows. In conclusion, biostimulation and social dominance influenced the ICR.


Subject(s)
Cattle/physiology , Estrous Cycle/physiology , Postpartum Period , Social Dominance , Animals , Corpus Luteum/growth & development , Female , Male , Progesterone/blood , Sexual Behavior, Animal , Social Behavior
9.
Ecotoxicology ; 21(7): 1965-78, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22623112

ABSTRACT

This study addresses the effects of soil polluted with more than one heavy metal in a grass species. A 16-week bioassay with Avena sativa L. was conducted in microcosms using soils from two abandoned mines in central Spain that contained levels above World Health Organization (WHO) reference limits for soils of more than three heavy metals. Pollution effects were examined at cell, tissue, organ, plant and population levels. For this purpose, dry weight, maximum height and number of leaves were determined; leaf tissues were observed by low temperature scanning electron microscopy; the metal contents of roots and shoots were determined by plasma emission spectroscopy and their distribution in different tissues was analyzed by X-ray microanalysis using an environmental scanning electron microscope. The results explain the accumulation and translocation of soil metals by this plant species; their effects in cells, tissues and growth of plants; and allow inference on population effects. The discussion of the methodological approach leads us to propose a valid protocol to assess the effects of a set of heavy metals present in the topsoil of polluted sites on a plant population. We recommend its use for an ecotoxicological diagnosis and risk analysis of similarly polluted sites.


Subject(s)
Avena/drug effects , Environmental Monitoring/methods , Metals, Heavy/toxicity , Soil Pollutants/toxicity , Avena/growth & development , Avena/metabolism , Avena/ultrastructure
10.
J Environ Manage ; 95 Suppl: S50-4, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21075508

ABSTRACT

Assessing the environmental impact of a soil-topped landfill requires an accurate ecotoxicological diagnosis. This paper describes various diagnostic protocols for this purpose and their application to a real case: the urban solid waste (USW) municipal landfill of Getafe (Madrid, Spain). After their initial sealing with soil from the surroundings about 20 years ago, most USW landfills in the autonomous community of Madrid have continued to receive waste. This has hindered precise assessment of their impact on their environment and affected ecosystems. The procedure proposed here overcomes this problem by assessing the situation in edaphic, aquatic and ecological terms. The present study focused on the most influential soil variables (viz. salinity due largely to the presence of anions, and heavy metals and organic compounds). These variables were also determined in surface waters of the wetland most strongly affected by leachates running down landfill slopes. Determinations included the characterization of plant communities and microbial biodiversity. The study was supplemented with a bioassay under controlled conditions in pots containing soil contaminated with variable concentrations of Zn (as ZnCl(2)) intended to assess ecochemical actions in a population of Bromus rubens, which grows profusely in the landfill.


Subject(s)
Ecotoxicology/methods , Refuse Disposal , Soil Pollutants/analysis , Soil , Biodiversity , Biota , Bromus , Metals, Heavy/analysis , Organic Chemicals/analysis , Plants , Soil Microbiology , Spain , Wetlands , Zinc/analysis
11.
J Environ Manage ; 95 Suppl: S285-90, 2012 Mar.
Article in English | MEDLINE | ID: mdl-20724060

ABSTRACT

Landfills are often the final recipient of a range of environmentally important contaminants such as hydrocarbons, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). In this study the influence of these contaminants on microbial activity and diversity was assessed in a municipal solid waste (MSW) landfill placed in Torrejón de Ardoz (Madrid, Spain). Soil samples were collected from four selected areas (T2, T2B, T8 and T9) in which the amount of total hydrocarbons, PAHs and PCBs were measured. Soil biomass, substrate induced respiration (SIR) and physiological profiles of soil samples were also determined and used as indicators of total microbial activity. Highest concentration of total hydrocarbons was detected in T2 and T9 samples, with both PCBs and benzopyrene being detected in T9 sample. Results corresponding to microbial estimation (viable bacteria and fungi, and SIR) and microbiological enzyme activities showed that highest values corresponded to areas with the lowest concentration of hydrocarbons (T2B and T8). It is noticeable that in such areas was detected the lowest concentration of the pollutants PAHs and PCBs. A negative significant correlation between soil hydrocarbons concentration and SIR, total bacteria and fungi counts and most of the enzyme activities determined was established. DGGE analysis was also carried out to determine the microbial communities' structure in the soil samples, establishing different profiles of Bacteria and Archaea communities in each analysed area. Through the statistical analysis a significant negative correlation was only found for Bacteria domain when Shannon index and hydrocarbon concentration were correlated. In addition, a bacterial 16S rRNA gene based clone library was prepared from each soil. From the clones analysed in the samples, the majority corresponded to Proteobacteria, followed by Acidobacteria and Actinobacteria. It is important to remark that the most polluted sample (T9) showed the lowest microbial diversity only formed by six phyla being Proteobacteria and Acidobacteria the most representative.


Subject(s)
Refuse Disposal/methods , Soil Microbiology , Soil Pollutants/toxicity , Xenobiotics/toxicity , Actinobacteria/drug effects , Actinobacteria/genetics , Bacteria/drug effects , Biodiversity , Fungi/drug effects , Fungi/genetics , Polychlorinated Biphenyls/toxicity , Polycyclic Aromatic Hydrocarbons/toxicity , Proteobacteria/drug effects , Proteobacteria/genetics , RNA, Ribosomal, 16S , Soil/chemistry , Soil Pollutants/analysis , Spain
12.
J Environ Manage ; 95 Suppl: S42-9, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21764209

ABSTRACT

This study was designed to determine the state of polluted soils in the main landfills of the Community of Madrid (central Spain), as part of a continuous assessment of the impacts of urban solid waste (USW) landfills that were capped with a layer of soil 20 years ago. Our analysis of this problem has been highly conditioned by the constant re-use of many of the USW landfills, since they have never been the target of any specific restoration plan. Our periodical analysis of cover soils and soils from discharge areas of the landfills indicates soil pollution has worsened over the years. Here, we examined heavy metal, salts, and organic compounds in soil and surface water samples taken from 15 landfills in the Madrid region. Impacts of the landfill soil covers on nematode and plant diversity were also evaluated. These analyses continue to reveal the presence of heavy metals (Zn, Cu, Cr, Ni, Pb, Cd) in soils, and salts (sulphates, chlorides and nitrates) in soils and surface waters. In addition, non-agricultural organic compounds, mainly aromatic and aliphatic hydrocarbons, often appeared in very high concentrations, and high levels of insecticides such as gamma-HCH (lindane) were also detected in soils. Around 50% of the water samples collected showed chemical demand of oxygen (CDO) values in excess of 150 mg/l. Traces of phenolic compounds were detected in some landfills, some of which exhibited high levels of 2-chlorophenol and pentachlorophenol. All these factors are conditioning both the revegetation of the landfill systems and the remediation of their slopes and terrestrial ecosystems arising in their discharge areas. This work updates the current situation and discusses risks for the health of the ecosystems, humans, domestic animals and wildlife living close to these landfills.


Subject(s)
Metals, Heavy/analysis , Organic Chemicals/analysis , Refuse Disposal/methods , Salts/analysis , Soil Pollutants/analysis , Water Pollutants, Chemical/analysis , Animals , Biodiversity , Biological Oxygen Demand Analysis , Chlorides/analysis , Cities , Environment , Insecticides/analysis , Nematoda , Nitrates/analysis , Plants , Soil Pollutants/chemistry , Spain , Sulfates/analysis
16.
Endoscopy ; 41(6): 532-8, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19533558

ABSTRACT

BACKGROUND AND STUDY AIMS: Endoscopic retrograde cholangiography (ERC) with stenting is the procedure of choice for biliary decompression in patients with obstructive jaundice. In cases where biliary access cannot be achieved, interventional endoscopic ultrasound-guided cholangiography (IEUC) has become an alternative to percutaneous transhepatic cholangiography (PTC). PATIENTS AND METHODS: We report on 5 years of experience in patients who underwent IEUC after failed endoscopic retrograde cholangiopancreatography (ERCP). Endoscopic ultrasound-guided access to the targeted biliary duct was attempted with one of two approaches: transgastric-transhepatic (intrahepatic) or transenteric-transcholedochal (extrahepatic). A stent was then advanced over the wire and into the biliary tree. RESULTS: A total of 49 patients underwent IEUC: 35 had biliary obstruction due to malignancy and 14 had a benign etiology. The overall success rate of IEUC was 84% (41/49), with an overall complication rate of 16%. Of the 35 patients who underwent the intrahepatic approach, 23 had a stent placed across the major papilla, one had a stent placed intraductally in the common bile duct, and three patients underwent placement of a gastrohepatic stent. Resolution of obstruction was achieved in 29 patients, with a success rate of 83%. In all, 14 patients underwent an extrahepatic approach. In 8/14 (57%), stent placement across the major papilla was achieved. A transenteric stent was placed in four patients. Biliary decompression was achieved in 12/14 cases (86%). Based on intention-to-treat analysis, the intrahepatic approach achieved success in 29 of 40 cases (73%), and the extrahepatic approach was successful in seven of nine cases (78%). There were no procedure-related deaths. CONCLUSION: IEUC offers a feasible alternative to PTC in patients with obstructive jaundice in whom ERC has failed.


Subject(s)
Cholangiography/methods , Cholestasis/diagnostic imaging , Endosonography , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Endoscopy, Digestive System , Feasibility Studies , Female , Humans , Male , Middle Aged , Radiography, Interventional/methods , Stents , Young Adult
17.
J Phys Condens Matter ; 21(14): 145401, 2009 Apr 08.
Article in English | MEDLINE | ID: mdl-21825332

ABSTRACT

The LiNbO(3) congruent crystals doped with small Nd concentrations, <1 mol% Nd, and co-doped with Mg ions, 0-9 mol% Mg, were systematically investigated by means of micro-Raman spectroscopy in the Y and Z crystal directions. Results obtained from an undoped congruent crystal, an Nd-doped crystal, a Mg-doped crystal and Nd, Mg-co-doped crystals are compared. From the analyses of the results obtained in the Y direction, the Nd and Mg content dependence of the two lowest-Raman A(1)(TO(1)) and A(1)(TO(2)) modes, the half-width composition and the area ratio of the A(1)(TO(4)) and E(TO(8)) bands, we reached several conclusions about the incorporation mechanism of the Nd and Mg ions into the LiNbO(3) lattice. Likewise the Raman shift and half-width of the E(TO(1)) and E(TO(7)) modes were investigated in the Z direction. Results indicate that Mg and Nd ions are located in the Li site for low doping concentrations and for larger concentrations there is a replacement in both Li and Nb ion sites.

18.
Environ Geochem Health ; 30(2): 127-33, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18246431

ABSTRACT

Abandoned metal mines in the Sierra de Guadarrama, Madrid, Spain, are often located in areas of high ecological value. This is true of an abandoned barium mine situated in the heart of a bird sanctuary. Today the area sustains grasslands, interspersed with oakwood formations of Quercus ilex and heywood scrub (Retama sphaerocarpa L.), used by cattle, sheep and wild animals. Our study was designed to establish a relationship between the plant biodiversity of these grasslands and the bioavailability of heavy metals in the topsoil layer of this abandoned mine. We conducted soil chemical analyses and performed a greenhouse evaluation of the effects of different soil heavy metal concentrations on biodiversity. The greenhouse bioassays were run for 6 months using soil samples obtained from the mine polluted with heavy metals (Cu, Zn, Pb and Cd) and from a control pasture. Soil heavy metal and Na concentrations, along with the pH, had intense negative effects on plant biodiversity, as determined through changes in the Shannon index and species richness. Numbers of grasses, legumes, and composites were reduced, whilst other species (including ruderals) were affected to a lesser extent. Zinc had the greatest effect on biodiversity, followed by Cd and Cu. When we compared the sensitivity of the biodiversity indicators to the different metal content variables, pseudototal metal concentrations determined by X-ray fluorescence (XRF) were the most sensitive, followed by available and soluble metal contents. Worse correlations between biodiversity variables and metal variables were shown by pseudototal contents obtained by plasma emission spectroscopy (ICP-OES). Our results highlight the importance of using as many different indicators as possible to reliably assess the response shown by plants to heavy metal soil pollution.


Subject(s)
Biodiversity , Metals, Heavy/analysis , Plants , Soil Pollutants/analysis , Environmental Monitoring , Mining , Sodium/analysis , Spain
19.
Radiat Prot Dosimetry ; 119(1-4): 280-4, 2006.
Article in English | MEDLINE | ID: mdl-16644984

ABSTRACT

The thermoluminescence (TL) behaviour of solid solutions of lead doped KCl(1-x)Br(x) (X = 0.02, 0.35, 0.50, 0.65, 0.85, 1) mixed crystals exposed to gamma radiation at different doses from 60Co is reported. The TL glow curves of KCl(1-x)Br(x):Pb2+ crystal exposed in the range of 0-140 Gy is strongly dependent on composition X. The maximum temperature of the main TL glow peak was found to shift towards lower temperatures as composition X increased and a significant enhancement of the TL efficiency in KCl(1-x)Br(x):Pb2+ was found for X = 0.50 which is attributed to an increase in the vacancy concentration of the mixed halides at middle composition. The participation of the F-centre in the TL phenomenon particularly related to the main TL glow peak observed in mixed samples was also confirmed.


Subject(s)
Models, Chemical , Potassium Chloride/chemistry , Potassium Chloride/radiation effects , Thermoluminescent Dosimetry/instrumentation , Bromides/chemistry , Bromides/radiation effects , Computer Simulation , Dose-Response Relationship, Radiation , Equipment Design , Equipment Failure Analysis , Gamma Rays , Lead/chemistry , Lead/radiation effects , Light , Materials Testing , Radiation Dosage , Thermoluminescent Dosimetry/methods
20.
Theriogenology ; 66(4): 710-6, 2006 Sep 01.
Article in English | MEDLINE | ID: mdl-16325900

ABSTRACT

The objective of this study was to evaluate the effect of biostimulation by bull exposure on the expression of estrus in postpartum Angus cows. Ninety Angus cows and their calves were allocated by parity and body frame to three pens (30/pen). From 1-week post partum, one epididectomized mature Angus bull was placed with Groups A and B (BE), whereas Group C served as a Control (NE). Data for duration of estrus (DE), total mounts received (TMR), and intensity of estrus (IE) were recorded using HeatWatch. At either the first or second postpartum estrus, there were no differences between BE and NE cows for DE, TMR and IE. However, the period after onset of estrus, cow within treatment and the interaction treatment by period exerted a significant influence on IE. Overall, the greatest IE (P<0.0001) was observed during the first two periods (6h). At the first postpartum estrus, IE tended (P<0.11) to be greater in BE than NE cows during the first 3h after onset of estrus. However, IE was greater (P<0.02) in NE cows than BE cows during 4-6h after onset of estrus. At the second postpartum estrus, IE did not differ between BE and NE cows during the first 3h after onset of estrus. However, from 4 to 9h after onset of estrus, IE was greater (P<006) in NE cows than BE cows. From the results of this study, it was concluded that DE, TMR and IE were not influenced by biostimulation. However, the manner in which mounting activities were distributed across the duration of estrus was influenced by the presence of bulls.


Subject(s)
Cattle/physiology , Estrus/physiology , Postpartum Period/physiology , Sexual Behavior, Animal/physiology , Social Environment , Animals , Behavior, Animal/physiology , Female , Male , Time Factors
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