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1.
Animal ; 18(5): 101158, 2024 May.
Article in English | MEDLINE | ID: mdl-38703756

ABSTRACT

The transformation of pastures from a degraded state to sustainable productivity is a major challenge in tropical livestock production. Stoloniferous forage legumes such as Arachis pintoi (forage peanut) are one of the most promising alternatives for intensifying pasture-based beef livestock operations with reduced greenhouse gas (GHG) emissions. This 2-year study assessed beef cattle performance, nutrient intake and digestibility, and balance of GHG emissions in three pasture types (PT): (1) mixed Palisade grass - Urochloa brizantha (Hochst. ex A. Rich.) R.D. Webster (syn. Brachiaria brizantha Stapf cv. Marandu) and forage peanut (A. pintoi Krapov. & W.C. Greg. cv. BRS Mandobi) pastures (Mixed), (2) monoculture Palisade grass pastures with 150 kg of N/ha per year (Fertilised), and (3) monoculture Palisade grass without N fertiliser (Control). Continuous stocking with a variable stocking rate was used in a randomised complete block design, with four replicates per treatment. The average daily gain and carcass gain were not influenced by the PT (P = 0.439 and P = 0.100, respectively) and were, on average, 0.433 kg/animal per day and 83.4 kg/animal, respectively. Fertilised and Mixed pastures increased by 102 and 31.5%, respectively, the liveweight gain per area (kg/ha/yr) compared to the Control pasture (P < 0.001). The heifers in the Mixed pasture had lower CH4 emissions (g/animal per day; P = 0.009), achieving a reduction of 12.6 and 10.1% when compared to the Fertilised and Control pastures, respectively. Annual (N2O) emissions (g/animal) and per kg carcass weight gain were 59.8 and 63.1% lower, respectively, in the Mixed pasture compared to the Fertilised pasture (P < 0.001). Mixed pasture mitigated approximately 23% of kg CO2eq/kg of carcass when substituting 150 kg of N/ha per year via fertiliser. Mixed pastures with forage peanut are a promising solution to recover degraded tropical pastures by providing increased animal production with lower GHG emissions.


Subject(s)
Animal Feed , Animal Husbandry , Arachis , Greenhouse Gases , Animals , Cattle/physiology , Animal Feed/analysis , Greenhouse Gases/analysis , Animal Husbandry/methods , Diet/veterinary , Male , Female , Animal Nutritional Physiological Phenomena , Digestion , Fabaceae
2.
J Med Econ ; 26(1): 1108-1121, 2023.
Article in English | MEDLINE | ID: mdl-37632452

ABSTRACT

OBJECTIVE: Nivolumab plus ipilimumab (NIVO + IPI) and pembrolizumab plus axitinib (PEM + AXI) have demonstrated significant clinical benefits as first-line (1 L) treatments for intermediate/poor-risk advanced renal cell carcinoma (aRCC) patients. This study aimed to assess the cost-effectiveness of NIVO + IPI versus PEM + AXI from a Brazilian private healthcare system perspective, utilizing a novel approach to estimate comparative efficacy between the treatments. METHODS: A three-state partitioned survival model (progression-free, progressed, and death) was developed to estimate costs, life-years (LYs), quality-adjusted LYs (QALYs), and the incremental cost-utility ratio (ICUR) over a 40-year time horizon. In the absence of head-to-head comparisons between NIVO + IPI and PEM + AXI, clinical data for NIVO + IPI was obtained from CheckMate 214 (NCT02231749) and for PEM + AXI from KEYNOTE-426 (NCT02853331). A matching-adjusted indirect comparison was conducted to account for the imbalance of treatment effect modifiers between the trials. Patient characteristics, resource use, health state utilities, and costs were based on Brazilian-specific sources. Costs and health outcomes were both discounted by 5% annually in line with Brazilian guidelines. The robustness of the results was evaluated through extensive sensitivity analysis and scenario analyses. RESULTS: When comparing the matched versus unmatched OS, PFS, and TTD curves there was no noteworthy difference. NIVO + IPI was associated with cost savings (R$ 350,232), higher LYs (5.54 vs. 4.61), and QALYs (4.74 vs. 3.76) versus PEM + AXI, resulting in NIVO + IPI dominating PEM + AXI. Key model drivers were the treatment duration for PEM, NIVO, and AXI. NIVO + IPI remained dominant in all scenario analyses, which indicated that model results were robust to alternative modelling inputs or assumptions. CONCLUSIONS: This analysis shows that NIVO + IPI is estimated to be a life-extending and potentially cost-saving 1 L treatment option when compared with PEM + AXI for intermediate/poor-risk a RCC patients in the Brazilian private healthcare system.


Subject(s)
Carcinoma, Renal Cell , Kidney Neoplasms , Humans , Nivolumab/therapeutic use , Ipilimumab/therapeutic use , Carcinoma, Renal Cell/drug therapy , Carcinoma, Renal Cell/pathology , Axitinib/therapeutic use , Prognosis , Cost-Benefit Analysis , Brazil , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Delivery of Health Care , Kidney Neoplasms/drug therapy , Kidney Neoplasms/pathology
3.
J Sci Med Sport ; 25(4): 281-286, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34895837

ABSTRACT

OBJECTIVES: Athletes performing sports on high level are at increased risk for sudden cardiac death. This includes paediatric athletes, even though data on screening strategies in this age group remain scarce. This study aimed to assess electrocardiogram interpretation criteria in paediatric athletes and to evaluate the cost of screening. METHODS: National, multicentre, retrospective, observational study on 891 athletes of paediatric age (<18 years) evaluated by history, physical examination and 12-lead electrocardiogram. The primary outcome measure was abnormal electrocardiogram findings according to the International Recommendations for Electrographic Interpretation in Athletes. The secondary outcome measure was cost of screening. RESULTS: 19 athletes (2.1%) presented abnormal electrocardiogram findings requiring further investigations, mainly abnormal T-wave inversion. These 19 athletes were predominantly males, performing endurance sports with a mean volume of 10 weekly hours for a mean duration of 6 years of training. Further investigations did not identify any relevant pathology. All athletes were cleared for competition with regular follow-up. Total costs of the screening were 108,860 USD (122 USD per athlete). CONCLUSIONS: Our study using the International Recommendations for Electrographic Interpretation in Athletes identified a low count of abnormal findings in paediatric athletes, yet raising substantially the cost of screening. Hence, the utility of electrocardiogram-inclusive screening of paediatric athletes remains to be elucidated by longitudinal data.


Subject(s)
Heart Diseases , Adolescent , Athletes , Child , Costs and Cost Analysis , Death, Sudden, Cardiac/prevention & control , Electrocardiography , Heart Diseases/diagnosis , Humans , Male , Retrospective Studies , Switzerland
4.
J Dairy Sci ; 104(10): 10828-10840, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34275635

ABSTRACT

There is an increasing recognition throughout the world that many of the feeding problems of dairy herds are linked to the presence of aerobically deteriorated parts on a silo face, causing farmers to pose questions on what amount of silage should be removed daily to feed their animals. Since an adequate feed-out rate helps to prevent silage spoilage, a simple tool is needed to manage the aerobic deterioration of corn silages during feed-out. The aims of this study were to develop an unloading rate index, which we have called the mass feed-out rate (MFR), expressed in kilograms of fresh matter silage unloaded daily per square meter of silo face, to better predict the aerobic deterioration of silage and to offer management solutions to help prevent spoilage, through a survey on 97 commercial dairy farms in Italy and Brazil. Silages were sampled and analyzed for their main microbial, fermentative, and nutritional characteristics, whereas silage temperatures were measured in the core and peripheral areas of the silo working face. Moreover, a detailed questionnaire on silo management and silage utilization was administered to the farmers during each farm visit. The size and silage density of the silos presented a wide variability in the 2 countries, thus indicating that different management practices were adopted during corn harvesting, silo filling, and silage compaction. The differences between pH and temperature in the peripheral areas and in the core of the silage (dpH and dT, respectively) were tested as a single indicator to identify any aerobic deteriorated areas on the silo face, associated with the yeast and mold counts. Both indicators correctly identified aerobic deterioration in 86.6% and 93.8% of the studied silos, respectively. The lactic acid and ethanol increased as the MFR increased, whereas the starch, dT, and the yeast and mold counts decreased with increasing MFR. A daily removal rate of over 250 kg of silage/m2 markedly reduced the risk of spoilage in corn silages at a farm level in both temperate and tropical environments. The new MFR index can substitute for the commonly used linear feed-out rate as it includes the silage density and can be obtained from 1 single recording.


Subject(s)
Silage , Zea mays , Aerobiosis , Animals , Fermentation , Fungi , Silage/analysis , Yeasts
5.
Arq. bras. med. vet. zootec. (Online) ; 71(6): 2009-2016, Nov.-Dec. 2019. tab
Article in English | LILACS, VETINDEX | ID: biblio-1055139

ABSTRACT

This study evaluated how changing the structure of Brachiaria brizantha cv. Marandu pasture under different forage allowances (FA) of 4, 7, 10 and 13kg DM/100kg BW (body weight) affected animal behavior over a two-year evaluation period. The experiment was conducted as a randomized block design with three replications (paddock). Sward height, total forage, and stem mass were lower for pastures managed with lower FA. Lower leaf mass was observed for lower FA in the second year. In hand-plucked samples, leaf and stem percentages remained unchanged in the morning but leaf percentage increased while stems decreased in the afternoon. Permanence time decreased linearly with increasing FA. In turn, a quadratic effect was observed for displacement rate. The bite rate was similar among different FAs. The results demonstrate that FA varying between 7 and 10kg DM/100kg BW are more suitable to balance the amounts of leaves and stems in the sward. The studied FA levels do not limit forage availability. Permanence time decreases and displacement rate increases as FA increases.(AU)


O objetivo foi avaliar como mudanças na estrutura de pastos de Brachiaria brizantha cv. Marandu, sob diferentes ofertas de forragem (OF) de 4, 7, 10 e 13kg MS/100kg PC, afetam o comportamento animal durante um período de avaliação de dois anos. O delineamento utilizado foi em blocos ao acaso, com três repetições (piquetes). A altura do dossel, a massa de forragem total e de colmos foram menores em pastos manejados com menores OF. A menor massa de folhas foi observada na menor OF no segundo ano. Nas amostras de pastejo simulado, as porcentagens de folhas e colmos não diferiram pela manhã, mas a porcentagem de folhas aumentou, enquanto a de colmos diminuiu à tarde. O tempo de permanência dos animais diminuiu linearmente com o aumento das OF. Efeito quadrático foi observado para taxa de deslocamento. A taxa de bocados foi similar entre as OF. Os resultados demonstram que variar as OF entre 7 e 10kg MS/100kg PC é mais adequado para balancear as quantidades de folhas e colmos no dossel forrageiro. Os níveis de OF estudados não limitam a forragem disponível. O tempo de permanência diminuí e a taxa de deslocamento aumenta com o aumento das OF.(AU)


Subject(s)
Animals , Male , Cattle , Pasture , Eating , Feeding Behavior
6.
J Dairy Sci ; 102(10): 9039-9042, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31326162

ABSTRACT

The techniques used to assess pH in silages vary greatly. The aim of this study was to evaluate the effects of water-to-sample ratio, extraction procedure, and standing time on pH determination. Silage samples (n = 20 for each silage) were chosen to represent diverse crops (corn, elephant grass, sugarcane, and forage peanut) to have a varied ensilability index and thus a wide range in final pH. Three water-to-sample ratios and 2 extraction procedures were used to measure pH at 0, 5, 10, 15, 30, 60, and 120 min of standing time. The ratios (undried silage to water) were 9:60, 25:100, and 30:270. The samples with the first 2 ratios were manually extracted, using a glass beaker and a glass stirring rod. The samples with the 30:270 ratio were extracted by using a stomacher blender for 4 min at 200 rpm. An electrode was used to perform pH readings. Dry matter (DM), water-soluble carbohydrates, and lactic acid concentrations were determined. The experimental design was completely randomized using a mixed repeated-measures model. Mean separation was performed using the Tukey test at P < 0.10 using the MIXED procedure of SAS (SAS Institute Inc., Cary, NC). The DM concentrations ranged from 24.5 to 40.2, 15.8 to 25.9, 26.9 to 30.6, and 17.8 to 21.4% for corn, elephant grass, sugarcane, and forage peanut silages, respectively. The lactic acid concentrations ranged from 2.9 to 10.1, 1.8 to 4.4, 0.7 to 11.4, and 0.3 to 1.4% of DM for corn, elephant grass, sugarcane, and forage peanut silages, respectively. The pH values measured by the 9:60 method were greater than other techniques at any standing times. The pH values from the 25:100 and 30:270 methods did not differ for elephant grass and forage peanut silages at any standing times. However, the 30:270 method had greater pH values for corn and sugarcane silages than the 25:100 technique at any standing times. The pH values measured by the 30:270 method did not vary for any of the silages according to standing time. Nevertheless, the pH values of the 25:100 method were greater from 0 to 10 min than for other standing times for all silages. Thus, for this method, there was pH stabilization from 15 min of standing time on. Overall, the 25:100 and 30:270 methods are recommended for assessment of silage pH. Fifteen minutes of standing time should be used for the 25:100 method but the pH reading can be performed immediately after mixing for the 30:270 technique.


Subject(s)
Lactic Acid/analysis , Silage/analysis , Animals , Edible Grain , Fermentation , Hydrogen-Ion Concentration , Saccharum , Zea mays
7.
Orthopade ; 46(12): 1045-1054, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29085983

ABSTRACT

BACKGROUND: Posterior glenoid bone loss in primary glenohumeral osteoarthritis (GHOA) presents a challenge when considering replacement surgery. Results with anatomic shoulder arthroplasty are unpredictable due to posterior humeral instability and limited bone stock for glenoid component fixation. OBJECTIVES: To describe and evaluate the results of a "shaped" humeral head autograft with reverse shoulder arthroplasty (RSA) for the treatment of primary GHOA with significant posterior glenoid bone loss and an intact, functional rotator cuff. MATERIALS AND METHODS: We retrospectively reviewed 29 "shaped" humeral head autografts with RSA for the treatment of GHOA with B2 (n = 16), B3 (n = 10), or C (n = 3) glenoid morphology based on the Walch classification system. Average glenoid retroversion was 32.3°. Humeral head autografts were "shaped" to match each patient's individual glenoid morphology. Functional outcome scores, range of motion, strength, and radiographic outcomes were evaluated. RESULTS: At average follow-up of 34.6 months (range 23.7-88.9 months), significant improvements were seen in all functional outcome scores, ranges of motion, and strength (p <0.01). No recurrent instability or glenoid fixation failure occurred. Two complications (1 superficial and 1 deep infection) in 2 patients were identified. All autografts incorporated without radiographic evidence of loosening. Scapular notching was observed in 8 shoulders. No negative correlations were identified with glenoid morphology. CONCLUSIONS: "Shaped" humeral head autograft with RSA for the treatment of primary GHOA with significant posterior glenoid bone loss is associated with excellent clinical and radiographic outcomes and a low complication profile at short- to mid-term follow-up.


Subject(s)
Arthroplasty/methods , Autografts , Bone Transplantation/methods , Glenoid Cavity/surgery , Humeral Head/surgery , Osteoarthritis/surgery , Shoulder Joint/surgery , Aged , Follow-Up Studies , Glenoid Cavity/diagnostic imaging , Humans , Humeral Head/diagnostic imaging , Male , Osteoarthritis/diagnostic imaging , Postoperative Complications/diagnostic imaging , Postoperative Complications/etiology , Range of Motion, Articular/physiology , Retrospective Studies , Shoulder Joint/diagnostic imaging
8.
Obes Rev ; 18(8): 832-851, 2017 08.
Article in English | MEDLINE | ID: mdl-28524627

ABSTRACT

Imbalances in the gut microbiota, the bacteria that inhabit the intestines, are central to the pathogenesis of obesity. This systematic review assesses the association between the gut microbiota and weight loss in overweight/obese adults and its potential manipulation as a target for treating obesity. This review identified 43 studies using the keywords 'overweight' or 'obesity' and 'microbiota' and related terms; among these studies, 17 used dietary interventions, 11 used bariatric surgery and 15 used microbiota manipulation. The studies differed in their methodologies as well as their intervention lengths. Restrictive diets decreased the microbiota abundance, correlated with nutrient deficiency rather than weight loss and generally reduced the butyrate producers Firmicutes, Lactobacillus sp. and Bifidobacterium sp. The impact of surgical intervention depended on the given technique and showed a similar effect on butyrate producers, in addition to increasing the presence of the Proteobacteria phylum, which is related to changes in the intestinal absorptive surface, pH and digestion time. Probiotics differed in strain and duration with diverse effects on the microbiota, and they tended to reduce body fat. Prebiotics had a bifidogenic effect and increased butyrate producers, likely due to cross-feeding interactions, contributing to the gut barrier and improving metabolic outcomes. All of the interventions under consideration had impacts on the gut microbiota, although they did not always correlate with weight loss. These results show that restrictive diets and bariatric surgery reduce microbial abundance and promote changes in microbial composition that could have long-term detrimental effects on the colon. In contrast, prebiotics might restore a healthy microbiome and reduce body fat.


Subject(s)
Bariatric Surgery , Gastrointestinal Microbiome , Intestines/microbiology , Obesity/therapy , Overweight/therapy , Weight Loss/physiology , Humans , Obesity/diet therapy , Obesity/microbiology , Obesity/surgery , Overweight/diet therapy , Overweight/microbiology , Overweight/surgery
9.
J Dairy Sci ; 100(6): 4565-4573, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28390718

ABSTRACT

The objective of this study was to evaluate 2 systems for covering corn silage in bunker silos. The first system consisted of a sheet of 45-µm-thick oxygen barrier film (OB, polyethylene + ethylene-vinyl alcohol) placed along the length of the sidewall before filling. After filling, the excess film was pulled over the wall on top of the silage, and a sheet of polyethylene was placed on top. The second system involved using a standard sheet (ST) of 180-µm-thick polyethylene film. Eight commercial bunker silos were divided into 2 parts lengthwise so that one-half of the silo was covered with OB and the other half with a ST system. During the filling, 3 net bags with chopped corn were buried in the central part (halfway between the top and bottom of the silo) of the bunkers (CCOR) in 3 sections 10 m apart. After filling, 18 net bags (9 per covering system) were buried 40 cm below the top surface of the 3 sections. These bags were placed at 3 distances from the bunker walls (0 to 50 cm, 51 to 100 cm, and 101 to 150 cm). During unloading, the bags were removed from the silos to determine the dry matter (DM) losses, fermentation end products, and nutritive value. The Milk2006 spreadsheet was used to estimate milk per tonne of DM. The model included the fixed effect of treatment (7 different locations in the bunker) and the random effect of the silo. Two contrasts were tested to compare silages in the top laterals (shoulders) with that in the CCOR (CCOR vs. OB and CCOR vs. ST). Three contrasts compared the corresponding distances of the silage covered by the 2 systems (OB50 vs. ST50, OB100 vs. ST100 and OB150 vs. ST150). Variables were analyzed with the PROC MIXED procedure of the SAS at the 5% level. The OB method produced well-fermented silages, which were similar to CCOR, whereas the OB system showed less lactic acid and greater pH and mold counts compared with CCOR. The ST method had 116.2 kg of milk/t less than the CCOR, as the OB system and the CCOR were similar (1,258.3 and 1,294.0 kg/t, respectively). Regarding the distances from the walls, the effects were more pronounced from 0 to 101 cm. The OB50 and OB100 silages had better quality and lower mold counts and DM losses than ST50 and ST100. The OB system reduced DM and nutrient losses at the shoulders in farm bunker corn silages compared with no sidewall plastic. The OB film should lap onto the crop for at least 200 cm so that 150 cm are covered outward from the wall.


Subject(s)
Fermentation , Food Storage/methods , Nutritive Value , Oxygen , Plastics/chemistry , Silage , Zea mays , Animal Husbandry , Animals , Ethanol , Food Storage/instrumentation , Hydrogen-Ion Concentration , Lactic Acid/analysis , Polyethylene , Vinyl Compounds
10.
Genet Mol Res ; 15(1)2016 Mar 31.
Article in English | MEDLINE | ID: mdl-27051039

ABSTRACT

We verified the prevalence of human papillomavirus (HPV) E6/E7 protein mRNA expression in patients with low-grade squamous intraepithelial lesions (LSILs) and negative cervicovaginal cytology. To investigate the relationship between mRNA expression and viral infection type, we assessed genotyping in single infections. Samples from 825 women were submitted to the E6/E7 survey. We noticed a larger percentage of E6/E7 mRNA expression in the atypical squamous cells of undetermined significance (ASC-US) and LSIL cytologies. Negative results of mRNA expression were in accordance with negative cytologies. In positive cases, the infection by a single HPV type was most common, with type 16 being most prevalent. The expression of mRNA was most prevalent in ASC-US and LSIL cytologies, compared with the negative cytology. The infection by a HPV type was more frequent in cases of positive expression, with HPV type 16 being found most frequently. Patients with LSIL cytologies had a higher percentage of multiple infections.


Subject(s)
Oncogene Proteins, Viral/genetics , Papillomavirus E7 Proteins/genetics , RNA, Messenger/genetics , Repressor Proteins/genetics , Squamous Intraepithelial Lesions of the Cervix/genetics , Adolescent , Adult , Aged , Female , Humans , Middle Aged , Oncogene Proteins, Viral/metabolism , Papillomavirus E7 Proteins/metabolism , RNA, Messenger/metabolism , Repressor Proteins/metabolism , Squamous Intraepithelial Lesions of the Cervix/pathology , Squamous Intraepithelial Lesions of the Cervix/virology
11.
Arq. bras. med. vet. zootec ; 65(4): 1149-1157, Aug. 2013. tab
Article in Portuguese | LILACS | ID: lil-684474

ABSTRACT

Avaliaram-se os efeitos da substituição da monensina sódica pelo bicarbonato de sódio em dietas de novilhas em confinamento em relação ao desempenho animal, à conversão alimentar e ao parâmetro de fermentação ruminal. Foram utilizadas 56 novilhas mestiças, confinadas por 112 dias, submetidas a dietas com duas porcentagens de concentrado, 50% e 80% da matéria seca, com adição de monensina sódica ou bicarbonato de sódio, em fatorial 2x2. O volumoso utilizado para compor as dietas testadas foi composto de silagem de milho e cana-de-açúcar na proporção de 60:40, respectivamente. O nitrogênio amoniacal foi maior nos animais alimentos com dietas com alto grão. A monensina, na dieta 80:20, proporcionou maiores valores de nitrogênio amoniacal, uma e nove horas após o consumo da ração. O uso de bicarbonato promoveu os maiores valores de pH ruminal na dieta com 50% de concentrado, de seis a 18 horas após o consumo. Não houve efeito do aditivo sobre o desempenho animal. A alta inclusão de grãos na dieta propiciou aumento do desempenho animal e da eficiência alimentar. Conclui-se que o uso de bicarbonato de sódio em dietas para terminação de animais em confinamento é uma opção viável em substituição à monensina sódica para a manipulação da fermentação ruminal.


The effects of replacing monensin with sodium bicarbonate in diets for confined heifers on weight gain (WG), dry matter intake (DMI), feed:gain ratio (FGR) and rumen fermentation parameters were evaluated. Fifity six heifers were utilized (Santa Gertrudis x Braunvieh). Diets were formulated with two levels of concentrate (50% and 80% concentrate) with sodium monensin or sodium bicarbonate. The DMI was higest in heifers with an intake of 80% concentrate. There was not difference when the same concentrate levels were evaluated in relation to the DMI. The heifers at 80% concentrate showed highest WG. There was no significant difference in relation to WG between monensin and bicarbonate treatments and levels concentrate proportions. There were significant effects regarding FGR between treatments. The heifers on 80% concentrate showed lowest FGR. In the evaluation of N-NH3, the highest values were observed, on the whole, at 80:20 diets in relation to 50:50 diets. In the additive use, the monensin on 80:20 diets promoted the highest values of N-NH3 at 1 for 9 hours after feed intake. In the values of ruminal pH, the bicarbonate increased the values on 50:50 at 6 for18 hours after feed intake, in relation to the 80:20 diet. In this case, it was concluded that the use of sodium bicarbonate in diets for confined finishing heifers is a viable option for the replacement of monensin sodium.


Subject(s)
Animals , Sodium Bicarbonate/analysis , Diet , Ionophores/chemistry , Cattle/classification
12.
Environ Geochem Health ; 11(3-4): 187-92, 1989 Dec.
Article in English | MEDLINE | ID: mdl-24202429

ABSTRACT

Acid mine drainage is commonly associated with land disturbances that encounter and expose iron sulphides to oxidising atmospheric conditions. The attendant acidic conditions solubilise a host of trace metals. Within this flow regime the potential exists to contaminate surface drinking water supplies with a variety of trace materials. Accordingly, in evaluating the applications for mines located in the headwaters of water sheds, the pre-mining prediction of the occurrence of acid mine drainage is of paramount importance.There is general agreement among investigators that coal organic sulphur is a nonparticipant in acid mine drainage generation; however, there is no scientific documentation to support this concensus. Using simulated weathering, kinetic, mass balance, petrographic analysis and a peroxide oxidation procedure, coal organic sulphur is shown to be a nonparticipant in acid mine drainage generation. Calculations for assessing the acid-generating potential of a sedimentary rock should not include organic sulphur content.

14.
Science ; 195(4279): 675-6, 1977 Feb 18.
Article in English | MEDLINE | ID: mdl-17816416

ABSTRACT

The sulfur found in coal stems in large part from sulfur incorporation at the peat-forming stage. Ester sulfate (a carbon-oxygen-sulfur linkage) is a major contributor to the sulfur in peat and thus is an important determiner of the quantity and forms of sulfur eventually found in coal.

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