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101.
Gaming,States, and Tax Revenues—the Tortoise or the Hare: A CGE Comparative Assessment of Casino Resorts and Games‐Only Casinos 下载免费PDF全文
Theoretically speaking, heavy tax rates on gambling should dampen growth of the casino revenues. Indeed, a cursory glance at data across U.S. states suggests that more jobs and income are generated directly by the gaming industry when lower tax rates are applied. Using a detailed computable general equilibrium model, we evaluate the effects of a proposed machine‐based casino on New Jersey's economy as well as on the state's existing set of casino resorts in Atlantic City. We find few winners other than the state's tax coffers. 相似文献
102.
Partial characterization of digestive proteases of the three‐spot cichlid Cichlasoma trimaculatum (Günter 1867) 下载免费PDF全文
F.J. Toledo‐Solís G. Márquez‐Couturier A. Uscanga‐Martínez R. Guerrero‐Zárate N. Perales‐García R. Martínez‐García W.M. Contreras‐Sánchez S. Camarillo‐Coop C.A. Álvarez‐González 《Aquaculture Nutrition》2016,22(6):1230-1238
Partial characterization of digestive proteases in the three‐spot cichlid Cichlasoma trimaculatum juveniles was conducted. It was determined that there is higher alkaline proteases activity (3.95 ± 0.32 IU mg?1 protein) compared to acidic proteases (2.01 ± 0.57 IU mg?1 protein). Optimal temperature for alkaline proteases is 60 °C which resulted in more thermostability to temperature changes. On the other hand, optimal temperature for acidic proteases is 50 °C. Optimal pH for acidic proteases was pH 2, while for alkaline proteases, it was pH 10, which resulted in more stability in relation to pH changes than acidic protease. The use of specific inhibitors and the SDS‐PAGE electrophoresis analysis revealed seven types of bands for alkaline proteases, which make evident the main presence of serine proteases. In acidic proteases, more than 98 g kg?1 of the activity was inhibited with pepstatin A inhibitor. Therefore, it is evident that C. trimaculatum digestion is composed by acidic and alkaline proteases; thus, it should be considered an omnivorous fish. 相似文献
103.
Two year‐classes of Atlantic cod were reared in indoor tanks from November 2002 to November 2004. The average annual mortality was 21% and 36% for males and females respectively. The highest monthly mortality rates in females were observed around and during the spawning periods from March to July, maximally 7% and 20% for year‐class 2001 and 18% and 34% for year‐class 2000. The mortality in males was less dependent on season, reaching a maximum of 7% and 5% month?1 for year‐class 2001 and 2000 respectively. The maximum mortality during spawning increased with age from: 7%, 19% and 34% per month for 2‐, 3‐ and 4‐year‐old females respectively. The average gonadosomatic indices in 3‐ and 4‐year‐old mature females that died during the spawning periods were 22% and 26% respectively and most of them were spawning when they died. The results suggest that egg‐retention may have been the main cause of death in females during spawning. 相似文献
104.
B. F. Carvalho C. L. S. Ávila M. N. Pereira R. F. Schwan 《Grass and Forage Science》2017,72(2):355-368
The ensiling of sugarcane results in high dry‐matter (DM) loss, but the addition of glycerine may compensate for the loss during ensiling. Methanol is the most undesirable contaminant of crude glycerine destined for animal feeding. The aim of this study was to evaluate the ability of the yeast strain Pichia methanolica NCYC 1381 to reduce the methanol concentration in sugarcane silage inoculated with Lactobacillus hilgardii CCMA 0170 + glycerine. A randomized design consisted of four dose rates of glycerine (0, 4, 8 and 12% of fresh forage), three periods of silage fermentation (11, 34 and 68 d) and three combinations of microbial additives [L. hilgardii (LH), L. hilgardii plus P. methanolica (LH + PM) and without microbial additive (WI)]. The DM of the fresh sugarcane was 275 g kg?1. The linear reduction in neutral detergent fibre caused by glycerine inclusion was probably due to a dilution effect. The LH treatment increased the concentrations of the succinic, acetic and propionic acids, and 1,2‐propanediol, and reduced the yeast population. The LH + PM treatment increased DM loss of sugarcane silage with 12% glycerine and L. hilgardii CCMA 0170 (6·1 log cfu g?1 of FM) reduced the DM loss when compared to the silage without additives. Under the conditions of the experiment, the P. methanolica treatment did not reduce the methanol concentration in silage. 相似文献
105.
Berzas Nevado J. J. García Bermejo L. F. Martín-Álvarez P. J. Rodríguez Martín-Doimeadios R. C. 《Water, air, and soil pollution》2004,155(1-4):269-289
A systematic hydrochemical study of the endangered Ruidera Pools Natural Park (Central Spain) has been carried out. An alarming pollution state of the water, mainly caused by nitrate, was stated with values up to 62 mg L-1 and 40% of all water samples showing nitrate concentrations higher than 50 mg L-1. The groundwater was confirmed to be the origin of nitrate input into this hydrosystem. Multivariate statistical treatment of the analytical results for principal components, combined with hierarchical clustering of samples allowed us to describe the behaviour of this hydrosystem. From our findings, the pools can be classified in two main groups depending on the main source of the water input, which is either surface or groundwater. Simultaneously, a comprehensive study has been undertaken to achieve a characterization of sediments by analysing major components and heavy metal. From these analyses, no heavy metal pollution was found. 相似文献
106.
Growth,tissue metabolites and digestive functionality in Sparus aurata juveniles fed different levels of macroalgae,Gracilaria cornea and Ulva rigida 下载免费PDF全文
Antonio Jesús Vizcaíno Sara Isabel Mendes José Luis Varela Ignacio Ruiz‐Jarabo Rosa Rico Felix L. Figueroa Roberto Abdala Miguel Ángel Moriñigo Juan Miguel Mancera Francisco Javier Alarcón 《Aquaculture Research》2016,47(10):3224-3238
The aim of this study was to evaluate the inclusion of two macroalgae as dietary ingredients on growth, body composition, intermediate metabolism, intestinal enzymes and gut histology of Sparus aurata juveniles. Six isocaloric and isonitrogenous diets incorporating 5%, 15% or 25% of Gracilaria cornea or Ulva rigida meal were tested against a control diet. Duplicate groups of fifteen fish (14 g) were fed the experimental diets for 70 days. Growth performance showed an inverse linear relationship with the inclusion level of Gracilaria. Feed conversion ratio increased significantly in fish fed 25% Gracilaria. Ulva presented a quadratic relationship with the lowest SGR at 15% of inclusion. Fish fed 25% Ulva exhibited significantly lower lipid content than those fed control diet. Overall, metabolites did not show differences with specimens fed control diet, except for plasmatic glucose and muscle lactate. Intestinal proteolytic activity was reduced with the macroalgae inclusion level, but all fish showed the same enzyme pattern. The histological study revealed no negative effect on liver and intestine structure by the macroalgae inclusion. The present work demonstrated that these ingredients can be used in practical diets for sea bream, but a more comprehensive research is needed to determine the optimum dietary level in a longer feeding trial. 相似文献
107.
Gaping and loss of fillet firmness in farmed salmon (Salmo salar L.) closely correlated with post‐slaughter cleaning of the abdominal cavity 下载免费PDF全文
This study analysed the effect of cleaning intensity of the abdominal cavity and storage temperature from slaughter to the end of processing on the quality of farmed salmon (Salmo salar L.) fillets. These two parameters were manipulated in an experimental setup using in total thirty salmon with an average weight of 4.2 kg. The experiment was designed to imitate realistic scenarios in a normal production process in the Faroe Islands. The salmon stored at low temperatures had an average muscle temperature of 4.65°C, whereas the salmon stored at ambient temperature had an average muscle temperature of 11.27°C. After the salmon were gutted to remove all viscera except the kidney, the abdominal cavity was either rinsed lightly or meticulously cleansed of kidneys, all blood and bodily fluids. A wide range of quality and production parameters were measured either straight after cleaning or after the salmon had been stored in chipped ice at 1.5°C for 7 days. All measured parameters were analysed for possible correlations by principal component analysis (PCA). Blood and remains left in the abdominal cavity were shown to have a significant negative effect on fillet firmness (P < 0.01) and gaping (P < 0.01). The different storage temperatures between slaughter and gutting, tested in this experiment, did not significantly affect fillet firmness or gaping. However, the fillet colour showed significant negative correlation (P < 0.01) with the storage temperatures applied. 相似文献
108.
109.
Soil microbiological properties and its stratification ratios for soil quality assessment under different cover crop management systems in a semiarid vineyard 下载免费PDF全文
In vineyards in Spain, tillage and semiarid Mediterranean climatic conditions accelerate organic matter loss from the soil. Cover crops are a conservation management practice that can provoke changes in soil quality which requires evaluation. Stratification ratios of soil properties such as soil organic C and labile C fractions have been proposed for the assessment of soil quality under different soil management systems. Our objective was to study the effect of different cover crop management on various soil parameters and their stratification ratios. We evaluated three different soil managements in a Typic Haploxerept from NE Spain: conventional tillage (CT); 5‐y continuous cover crop of resident vegetation (RV); and 4‐y continuous cover crop of Festuca longifolia Thuill., followed by 1‐y Bromus catharticus L. after resowing (BV). We monitored soil organic C, particulate organic C, water soluble C, potentially mineralizable N, microbial biomass C, β‐glucosidase and urease enzymatic activities, and water stable aggregates at 0–2.5, 2.5–5, 5–15, 15–25, and 25–45 cm soil depths. We calculated soil depth stratification ratios of those soil properties. Resident cover crop increased microbiological properties, labile C fractions, and aggregation with respect to conventional tillage at 0–2.5 and 2.5–5 cm soil depths. However, for Bromus cover crop the same soil properties were lower than for the resident cover crop at 0–2.5 cm depth. Stratification ratios of β‐glucosidase and urease enzymatic activities, and particulate organic C showed a higher sensitivity than other soil properties; therefore, they would be the best indicators for soil quality assessment in semiarid Mediterranean vineyards. 相似文献
110.
The compensation heat pulse (CHP) method is widely used to estimate sap flow and transpiration in conducting organs of woody plants. Previous studies have reported a natural azimuthal variability in sap flow, which could have practical implications in locating the CHP probes and integrating their output. Sap flow of several olive trees (Olea europaea L. cv. 'Arbequina') previously grown under different irrigation treatments were monitored by the CHP method, and their xylem anatomical characteristics were analyzed from wood samples taken at the same location in which the probes were installed. A significant azimuthal variability in the sap flow was found in a well-irrigated olive tree monitored by eight CHP probes. The azimuthal variability was well related to crown architecture, but poorly to azimuthal differences in the xylem anatomical characteristics. Well-irrigated and deficit-irrigated olive trees showed similar xylem anatomical characteristics, but they differed in xylem growth and in the ratio of nocturnal-to-diurnal sap flow (N/D index). The results of this work indicate that transpiration cannot be accurately estimated by the CHP method in olive trees if a small number of sensors are employed and that the N/D index could be used as a sensitive water status indicator. 相似文献