Anaerobic co-digestion of food waste and dairy manure: effects of food waste particle size and organic loading rate.

Science.gov (United States)

Agyeman, Fred O; Tao, Wendong

2014-01-15

This study was to comprehensively evaluate the effects of food waste particle size on co-digestion of food waste and dairy manure at organic loading rates increased stepwise from 0.67 to 3 g/L/d of volatile solids (VS). Three anaerobic digesters were fed semi-continuously with equal VS amounts of food waste and dairy manure. Food waste was ground to 2.5 mm (fine), 4 mm (medium), and 8 mm (coarse) for the three digesters, respectively. Methane production rate and specific methane yield were significantly higher in the digester with fine food waste. Digestate dewaterability was improved significantly by reducing food waste particle size. Specific methane yield was highest at the organic loading rate of 2g VS/L/d, being 0.63, 0.56, and 0.47 L CH4/g VS with fine, medium, and coarse food waste, respectively. Methane production rate was highest (1.40-1.53 L CH4/L/d) at the organic loading rate of 3 g VS/L/d. The energy used to grind food waste was minor compared with the heating value of the methane produced. Copyright © 2013 Elsevier Ltd. All rights reserved.

Psychrophilic anaerobic digestion of guinea pig manure in low-cost tubular digesters at high altitude.

Science.gov (United States)

Garfí, Marianna; Ferrer-Martí, Laia; Villegas, Vidal; Ferrer, Ivet

2011-05-01

Guinea pig is one of the most common livestock in rural communities of the Andes. The aim of this research was to study the anaerobic digestion of guinea pig manure in low-cost unheated tubular digesters at high altitude. To this end, the performance of two pilot digesters was monitored during 7 months; and two greenhouse designs were compared. In the dome roof digester the temperature and biogas production were significantly higher than in the shed roof digester. However, the biogas production rate was low (0.04 m(biogas)(3)m(digester)(-3) d(-1)), which is attributed to the low organic loading rate (0.6 kg(VS)m(digester)(-3)d(-1)) and temperature (23°C) of the system, among other factors. In a preliminary fertilization study, the potato yield per hectare was increased by 100% using the effluent as biofertilizer. Improving manure management techniques, increasing the organic loading rate and co digesting other substrates may be considered to enhance the process. Copyright © 2011 Elsevier Ltd. All rights reserved.

Nutrient digestibility response to sugarcane bagasse addition and corn particle size in normal and high Na diets for broilers.

Science.gov (United States)

Kheravii, S K; Swick, R A; Choct, M; Wu, S-B

2018-04-01

Improving diet digestibility is important to the broiler industry. Therefore, this study focused on optimizing the physical structure of feed ingredients and addition of dietary fiber as strategies to improve nutrient digestibility in low and high sodium diets. A total of 672 day-old Ross 308 male broilers was allocated to 48 pens using a 2 × 2 × 2 factorial arrangement of treatments with 2 particle sizes of corn (coarse 3,576 μm or fine 1,113 μm geometric mean diameter), 2 levels of sugarcane bagasse (SB) (0 or 2%), and 2 levels of Na (0.16 or 0.4%). Protein digestibility coefficient was measured using pooled distal ileal digesta of 3 birds per pen on d 24. Meanwhile, starch and gross energy digestibility coefficients were measured using pooled duodenal, distal jejunal, and distal ileal digesta of 3 birds per pen on d 24. Coarsely ground corn (CC) resulted in improved ileal protein digestibility (P digestibility in the duodenum (P digestibility in distal ileum (P digestibility (P digestibility only in birds fed the diet with finely ground corn (FC) and 0.16% Na. These findings demonstrate that SB and CC are able to improve nutrient digestibility. It can be recommended for the poultry industry to use SB and coarsely ground corn in feed to improve the utilization of nutrients.

Rural versus nonrural differences in BMC, volumetric BMD, and bone size: a population-based cross-sectional study.

Science.gov (United States)

Specker, Bonny; Binkley, Teresa; Fahrenwald, Nancy

2004-12-01

Despite reports of lower fracture risk among rural versus urban populations, few studies have investigated rural versus urban differences in bone mineral content (BMC) and bone mineral density (BMD). Population differences in cross-sectional bone geometry and understanding lifestyle factors responsible for these differences may reveal insights into the reason for differences in fracture risk. We hypothesized that if lifestyle differences in bone mass, size, and geometry are a result of muscle strength, activity, or dietary differences, Hutterite and rural populations should have greater bone mass compared to nonrural populations. The study population consisted of 1189 individuals: 504 rural Hutterites (188 men), 349 rural individuals (>75% life farming, 184 men), and 336 nonrural individuals (never lived on farm, 134 men) aged 20 to 66 years. BMC, bone area, and areal BMD (aBMD) of the total body (TB), hip, femoral neck (FN), and spine by DXA; volumetric BMD (vBMD) and bone geometry at the 4% and 20% radius; polar stress strain index (pSSI), a measure of bone strength, at the 20% pQCT site; and strength, 7-day activity recall, and 24-h diet recall were collected and compared among groups. Hutterite women and men had greater grip strength compared to rural and nonrural populations (both, P BMC and areal size than the nonrural population, while Hutterites had greater BMC and areal size than rural population at some (TB, FN for females only), but not all (proximal hip), sites. Cortical vBMD was inversely associated with periosteal circumference at the 20% radius in women (r=-0.25, P BMC, aBMD, vBMD, or bone size.

Assessment of the influence of amylose-LPC complexation on the extent of wheat starch digestibility by size-exclusion chromatography.

Science.gov (United States)

Ahmadi-Abhari, S; Woortman, A J J; Hamer, R J; Loos, K

2013-12-15

Amylose forms inclusion complexes with lysophosphatidylcholine (LPC), that decrease the susceptibility of amylose to amylase degradation. This study on the influence of complexation on starch susceptibility to amylase explains the nature of this protective effect. Wheat starch suspensions (9% w/w) containing 0.5-5% LPC were subjected to hydrolysis by porcine pancreatic α-amylase at 37 °C for several digestion times. The digesta were analysed by size-exclusion chromatography (SEC). The molar mass distribution was closely dependent on the digestion time and amount of LPC. This study precisely demonstrates the alteration of the digestion profile of starch on a molecular level, influenced by amylose-LPC complexation; however the effect depends on the digestion time. During 15 and 30 min digestion, inclusion complexes not only protect amylopectin in the initial hydrolysis stage, but also demonstrate lower susceptibility of the molecular amylose complexes to amylase hydrolysis. Digestion for 240 min resulted in a lower oligosaccharide peak concentration, in the presence of a high LPC concentration, which is related to less degradation of complexed amylose fraction. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effects on roughage inclusion and particle size on digestion and ruminal fermentation characteristics of beef steers

Science.gov (United States)

Roughage is fed to cattle to promote ruminal health and decrease digestive upset, but inclusion in finishing diets is limited due to the cost per unit of energy. Rumination behavior may be a means to standardize roughage in beef cattle finishing diets, and increasing particle size of roughage could ...

Size effects on acid bisulfite pretreatment efficiency: multiple product yields in spent liquor and enzymatic digestibility of pretreated solids

Science.gov (United States)

Yalan Liu; Jinwu Wang; Michael P. Wolcott

2017-01-01

Currently, feedstock size effects on chemical pretreatment performance were not clear due to the complexity of the pretreatment process and multiple evaluation standards such as the sugar recovery in spent liquor or enzymatic digestibility. In this study, we evaluated the size effects by various ways: the sugar recovery and coproduct yields in spent liquor, the...

Determination of denaturated proteins and biotoxins by on-line size-exclusion chromatography-digestion-liquid chromatography-electrospray mass spectrometry

NARCIS (Netherlands)

Carol, J.; Gorseling, M.C.J.K.; Jong, C.F. de; Lingeman, H.; Kientz, C.E.; Baar, B.L.M. van; Irth, H.

2005-01-01

A multidimensional analytical method for the rapid determination and identification of proteins has been developed. The method is based on the size-exclusion fractionation of protein-containing samples, subsequent on-line trypsin digestion and desalination, and reversed-phase high-performance liquid

Forage fiber effects on particle size reduction, ruminal stratification, and selective retention in heifers fed highly digestible grass/clover silages.

Science.gov (United States)

Schulze, A K S; Weisbjerg, M R; Storm, A C; Nørgaard, P

2014-06-01

The objective of this study was to investigate the effect of NDF content in highly digestible grass/clover silage on particle size reduction, ruminal stratification, and selective retention in dairy heifers. The reduction in particle size from feed to feces was evaluated and related to feed intake, chewing activity, and apparent digestibility. Four grass/clover harvests (Mixtures of Lolium perenne, Trifolium pratense, and Trifolium repens) were performed from early May to late August at different maturities, at different regrowth stages, and with different clover proportions, resulting in silages with NDF contents of 312, 360, 371, and 446 g/kg DM, respectively, and decreasing NDF digestibility with greater NDF content. Four rumen-fistulated dairy heifers were fed silage at 90% of ad libitum level as the only feed source in a 4 × 4 Latin square design. Silage, ingested feed boluses, medial and ventral ruminal digesta, and feces samples were washed with neutral detergent in nylon bags of 10-μm pore size, freeze dried, and divided into small (1 mm) particles by dry-sieving. Chewing activity, rumen pool size, and apparent digestibility were measured. Intake of NDF increased linearly from 2.3 to 2.8 kg/d with greater NDF content of forages (P = 0.01), but silages were exposed to similar eating time (P = 0.55) and rumination time per kg NDF (P = 0.35). No linear effect of NDF content was found on proportion of LP in ingested feed boluses (P = 0.31), medial rumen digesta (P = 0.95), ventral rumen digesta (P = 0.84), and feces (P = 0.09). Greater proportions of DM (P ruminal digesta compared with ventral rumen, and differences in DM proportion increased with greater NDF content (P = 0.02). Particle size distributions were similar for digesta from the medial and ventral rumen regardless of NDF content of the silages (P > 0.13). The LP proportion was >30% of particles in the ventral and medial rumen, whereas in the feces, the LP proportion was content of the silages

Impact of government subsidies on household biogas use in rural China

International Nuclear Information System (INIS)

Sun, Dingqiang; Bai, Junfei; Qiu, Huanguang; Cai, Yaqing

2014-01-01

In this paper, we evaluate empirically the impact of biogas subsidies on household biogas energy use in rural China. Special attention was given to the problem of sample selection bias in assessing the impact of subsidies on biogas energy use because biogas subsidies often change the propensity for installing biogas digesters. Using data from a large-scale household survey, the results indicate that biogas subsidies did promote the construction of biogas digesters. The results suggest that a 10 percentage point increase in subsidy-cost ratio would lead to a 3% increase in digester installations. We also found that biogas subsidies correlated negatively with average time of digester use. A 10 percentage point increase in the subsidy-cost ratio would result in a 4.3% reduction in the average working time of digesters. These results suggest that the net effect of the current subsidy policy on rural household biogas use was near-negligible. Indeed, a 10 percentage point increase in the subsidy-cost ratio resulted in a mere 1.15% increase in biogas use. These findings indicate that biogas subsidies have possibly not been targeted effectively at households that would actually prefer to use biogas energy. - Highlights: • We evaluate empirically the impact of biogas subsidies on household biogas energy use in rural China. • Results indicate that biogas subsidies did promote the construction of biogas digesters. • We also find that biogas subsidies were correlated negatively with average time of digester use. • The results suggest that the net effect of the current subsidy policy on rural household biogas use was near-negligible. • A 10 percentage point increase in the subsidy-cost ratio leads to merely 1.15% increases in biogas use

Child health, nutrition and family size: a comparative study of rural and urban children.

Science.gov (United States)

Balderama-guzman, V

1978-01-01

771 children from Baras, Rizal, and Pasay City, Philippines were studied. House interviews of mothers using precoded questionnaires were conducted and the children were given a complete physical examination. The study objectives were to compare the health and nutritional status of children in a rural and an urban area in greater Manila and to determine how family size affects the nutritional status of children 3 years and younger. The following were among the study results: 1) the weight curves of both urban and rural groups were similar until age 4-1/2 years, but beyond this age the mean weight curve of the rural group exceeded that of the urban group; 2) urban children between ages 1-5 enjoyed a height advantage; 3) there was a positive correlation between malnutrition and excessive family size; 4) the high prevalence of malnutrition among children 1-4 years of age was due to food deprivation because of poverty, parental ignorance, inappropriate folklores, oversized families, high episodes of illnesses, and inadequate medical care; and 5) dietary assessment of both groups showed the inadequacy of the quality and quantity of basic nutrients and elements needed for growth, development, and repair of tissues.

Effect of the particle size of maize, rice, and sorghum in extruded diets for dogs on starch gelatinization, digestibility, and the fecal concentration of fermentation products.

Science.gov (United States)

Bazolli, R S; Vasconcellos, R S; de-Oliveira, L D; Sá, F C; Pereira, G T; Carciofi, A C

2015-06-01

The influence of rice, maize, and sorghum raw material particle size in extruded dry dog food on the digestibility of nutrients and energy and the fecal concentration of fermentation products was investigated. Three diets with similar nutrient compositions were formulated, each with 1 starch source. Before incorporation into diets, the cereals were ground into 3 different particle sizes (approximately 300, 450, and 600 µm); therefore, a total of 9 diets were in a 3 × 3 factorial arrangement (3 cereals and 3 particle sizes). Fifty-four beagle dogs (12.0 ± 0.1 kg BW) were randomly assigned to the diets, with 6 dogs per diet. The digestibility was measured with the chromium oxide method. The data were evaluated with ANOVA considering the carbohydrate source, grinding effect, and interactions. The means were compared with the Tukey test and polynomial contrasts (P 0.05); only GE digestibility was reduced at the largest MGD (P production of feces with less lactate (P dogs fed maize and sorghum foods, an increase in propionate and butyrate concentrations were observed as MGD increased (P dogs fed different particle sizes of the cereal starches in the extruded diets, the digestibility and fecal characteristics were affected, and this effect was ingredient dependent.

Effect of dietary fiber and diet particle size on nutrient digestibility and gastrointestinal secretory function in growing pigs

Science.gov (United States)

Effect of diet composition (DC) and particle size (PS) on nutrient digestibility, gastrointestinal hormones, total bile acids (TBA), total cholesterol and glucose concentrations in plasma were evaluated in finishing pigs (n=8/diet) fed finely (374±29 µm) or coarsely (631±35 µm) ground corn-soybean m...

Geographical Mobility, Income, Life Satisfaction and Family Size Preferences: An Empirical Study on Rural Households in Shaanxi and Henan Provinces in China.

Science.gov (United States)

Chen, Jiangsheng; Yang, Hong

Employing data from the China rural-urban mobility survey conducted in 2010, this study investigates the influence of family demographic characteristics on the income, life satisfaction, and potential for rural-urban mobility at the rural household level of two provinces of China: Shaanxi and Henan. A larger labor force in a rural household was found to reduce a family's ability or inclination to move to a city. The findings reveal that family size negatively affects the average income per family member and reduces the marginal income of the labor force and that minor children can improve the life satisfaction of family members. We conclude that a larger family size does not translate to more benefits for a rural household. Family size preference is found to be a reflection of parents' concerns about elderly care and is deemed to be unfavorable for urbanization in P. R. China.

Effect of raw soya bean particle size on productive performance and digestion of dairy cows.

Science.gov (United States)

Naves, A B; Freitas Júnior, J E; Barletta, R V; Gandra, J R; Calomeni, G D; Gardinal, R; Takiya, C S; Vendramini, T H A; Mingoti, R D; Rennó, F P

2016-08-01

Differing soya bean particle sizes may affect productive performance and ruminal fermentation due to the level of fatty acid (FA) exposure of the cotyledon in soya bean grain and because the protein in small particles is more rapidly degraded than the protein in large particles, which influence ruminal fibre digestion and the amounts of ruminally undegradable nutrients. The objective of this experiment was to investigate the effects of raw soya bean particle size on productive performance, digestion and milk FA profile of dairy cows. Twelve Holstein cows were assigned to three 4 × 4 Latin squares with 21-day periods. At the start of the experiment, cows were 121 days in milk (DIM) and yielded 30.2 kg/day of milk. Cows were fed 4 diets: (i) control diet (CO), without raw soya bean; (ii) whole raw soya bean (WRS); (iii) cracked raw soya bean in Wiley mill 4-mm screen (CS4); and (iv) cracked raw soya bean in Wiley mill 2-mm screen (CS2). The inclusion of soya beans (whole or cracked) was 200 g/kg on dry matter (DM) basis and partially replaced ground corn and soya bean meal. Uncorrected milk yield and composition were not influenced by experimental diets; however, fat-corrected milk (FCM) decreased when cows were fed soya bean treatments. Soya bean diets increased the intake of ether extract (EE) and net energy of lactation (NEL ), and decreased the intake of DM and non-fibre carbohydrate (NFC). Ruminal propionate concentration was lower in cows fed WRS than cows fed CS2 or CS4. Cows fed cracked raw soya bean presented lower nitrogen in faeces than cows fed WRS. The milk of cows fed WRS, CS2 and CS4 presented higher unsaturated FA than cows fed CO. The addition of raw soya bean in cow diets, regardless of the particle size, did not impair uncorrected milk yield and nutrient digestion, and increased the concentration of unsaturated FA in milk. Cows fed cracked raw soya bean presented similar productive performance to cows fed whole raw soya bean. Journal of

Diets high in resistant starch and arabinoxylan modulate digestion processes and SCFA pool size in the large intestine and faecal microbial composition in pigs.

Science.gov (United States)

Nielsen, Tina S; Lærke, Helle N; Theil, Peter K; Sørensen, Jens F; Saarinen, Markku; Forssten, Sofia; Knudsen, Knud E Bach

2014-12-14

The effects of a high level of dietary fibre (DF) either as arabinoxylan (AX) or resistant starch (RS) on digestion processes, SCFA concentration and pool size in various intestinal segments and on the microbial composition in the faeces were studied in a model experiment with pigs. A total of thirty female pigs (body weight 63.1 (sem 4.4) kg) were fed a low-DF, high-fat Western-style control diet (WSD), an AX-rich diet (AXD) or a RS-rich diet (RSD) for 3 weeks. Diet significantly affected the digestibility of DM, protein, fat, NSP and NSP components, and the arabinose:xylose ratio, as well as the disappearance of NSP and AX in the large intestine. RS was mainly digested in the caecum. AX was digested at a slower rate than RS. The digesta from AXD-fed pigs passed from the ileum to the distal colon more than twice as fast as those from WSD-fed pigs, with those from RSD-fed pigs being intermediate (PEubacterium rectale, Bifidobacterium spp. and Lactobacillus spp. in the faeces sampled at week 3 of the experimental period (P< 0.05). In the caecum, proximal and mid colon, AXD feeding resulted in a 3- to 5-fold higher pool size of butyrate compared with WSD feeding, with the RSD being intermediate (P <0.001). In conclusion, the RSD and AXD differently affected digestion processes compared with the WSD, and the AXD most efficiently shifted the microbial composition towards butyrogenic species in the faeces and increased the large-intestinal butyrate pool size.

Electricity purchase agreements and distributed energy policies for anaerobic digesters

International Nuclear Information System (INIS)

Binkley, David; Harsh, Stephen; Wolf, Christopher A.; Safferman, Steven; Kirk, Dana

2013-01-01

Anaerobic digestion is increasingly recognized for its ability to produce renewable energy and reduce greenhouse gas emissions from livestock operations. In 2010, there were 2645 U.S. dairy farms with herd sizes large enough to support anaerobic digesters, yet only 156 systems were in operation (U.S. Environmental Protection Agency (U.S. EPA), 2010a. Market Opportunities for Biogas Recovery Systems at U.S. Livestock Facilities. AgSTAR Program; U.S. Environmental Protection Agency (U.S. EPA), 2011. Operational Anaerobic Digesters, Sorted by State (Dairy). AgSTAR Program.). This study analyzes the net present value of digester systems under alternative electricity purchase agreements and how returns are affected by standby charges, net metering policies and the use of feed-in-tariffs. In order for digester potential to be fully realized on a state or national level, changes to distributed energy policy are required. Results indicated that standby charges can reduce revenues from offsetting electricity by an average of nearly 20%. Net metering rules limit participation among larger farms and negatively affect profitability by restricting engine–generator size. Lastly, the effectiveness of a fixed price feed-in-tariff policy for digesters is significantly affected by project size differentiation. Digester energy policies are similar nationwide, making this study useful for government regulatory agencies and digester owners throughout the U.S. - Highlights: ► Anaerobic digester net present value was examined over a range of herd sizes. ► Standby charges reduce electricity sales revenues by an average of nearly 20%. ► Net metering rules reduce profitability by restricting engine–generator size. ► Feed-in-tariffs for digesters are significantly affected by project size.

Economies of scale and firm size optimum in rural water supply

Science.gov (United States)

Sauer, Johannes

2005-11-01

This article is focused on modeling and analyzing the cost structure of water-supplying companies. A cross-sectional data set was collected with respect to water firms in rural areas of former East and West Germany. The empirical data are analyzed by applying a symmetric generalized McFadden (SGM) functional form. This flexible functional form allows for testing the concavity required by microeconomic theory as well as the global imposition of such curvature restrictions without any loss of flexibility. The original specification of the SGM cost function is modified to incorporate fixed factors of water production and supply as, for example, groundwater intake or the number of connections supplied. The estimated flexible and global curvature correct cost function is then used to derive scale elasticities as well as the optimal firm size. The results show that no water supplier in the sample produces at constant returns to scale. The optimal firm size was found to be on average about three times larger than the existing one. These findings deliver evidence for the hypothesis that the legally set supplying areas, oriented at public administrative criteria as well as local characteristics of water resources, are economically inefficient. Hence structural inefficiency in the rural water sector is confirmed to be policy induced.

Effects of feeding level and NDF content of grass-clover silages on chewing activity, fecal particle size and NDF digestibility in dairy heifers

DEFF Research Database (Denmark)

Schulze, Anne-Katrine Skovsted; Weisbjerg, Martin Riis; Nørgaard, Peder

2014-01-01

intake (PRumination time per kg DM intake (Pcontents (Prumination with greater...... NDF content (Prumination time increased with greater NDF content (Pcontent (P...The objective of this study was to assess effects of feed intake and NDF content of highly digestible grass-clover silage on chewing behavior, fecal particle size distribution and apparent digestibility in restrictively fed heifers. Four grass-clover silages (Lolium perenne, Trifolium pratense...

Oxidative potential of size-fractionated atmospheric aerosol in urban and rural sites across Europe.

Science.gov (United States)

Shafer, Martin M; Hemming, Jocelyn D C; Antkiewicz, Dagmara S; Schauer, James J

2016-07-18

In this study we applied several assays, an in vitro rat alveolar macrophage model, a chemical ROS probe (DTT, dithiothreitol), and cytokine induction (TNFα) to examine relationships between PM-induced generation of reactive oxygen species (ROS) and PM composition, using a unique set of size-resolved PM samples obtained from urban and rural environments across Europe. From April-July 2012, we collected PM from roadside canyon, roadside motorway, and background urban sites in each of six European cities and from three rural sites spanning the continent. A Hi-Vol sampler was used to collect PM in three size classes (PM>7, PM7-3, PM3) and PM was characterized for total elements, and oxidative activity quantified in unfiltered and filtered PM extracts. We measured a remarkable uniformity in air concentrations of ROS and especially DTT activity across the continent. Only a 4-fold difference was documented for DTT across the urban sites and a similar variance was documented for ROS, implying that chemical drivers of oxidative activity are relatively similar between sites. The ROS and DTT specific activity was greater at urban background sites (and also rural sites) than at urban canyon locations. PM3 dominated the size distribution of both ROS activity (86% of total) and DTT activity (76% of total), reflecting both the large contribution of PM3 to total PM mass levels and importantly the higher specific oxidative activity of the PM3 in comparison with the larger particles. The soluble fraction of total activity was very high for DTT (94%) as well as for ROS (64%) in the PM3. However in the larger PM size fractions the contributions of the insoluble components became increasingly significant. The dominance of the insoluble PM drivers of activity was particularly evident in the TNFα data, where the insoluble contribution to cytokine production could be 100-fold greater than that from soluble components. ROS and DTT activity were strongly correlated in the PM3 (r = 0

Examining the relationship between school district size and science achievement in Texas including rural school administrator perceptions of challenges and solutions

Science.gov (United States)

Mann, Matthew James

Rural and small schools have almost one-third of all public school enrollment in America, yet typically have the fewest financial and research based resources. Educational models have been developed with either the urban or suburban school in mind, and the rural school is often left with no other alternative except this paradigm. Rural based educational resources are rare and the ability to access these resources for rural school districts almost non-existent. Federal and state based education agencies provide some rural educational based programs, but have had virtually no success in answering rural school issues. With federal and state interest in science initiatives, the challenge that rural schools face weigh in. To align with that focus, this study examined Texas middle school student achievement in science and its relationship with school district enrollment size. This study involved a sequential transformative mixed methodology with the quantitative phase driving the second qualitative portion. The quantitative research was a non-experimental causal-comparative study conducted to determine whether there is a significant difference between student achievement on the 2010 Texas Assessment of Knowledge and Skills 8 th grade science results and school district enrollment size. The school districts were distributed into four categories by size including: a) small districts (32-550); b) medium districts (551-1500); c) large districts (1501-6000); and d) mega-sized districts (6001-202,773). A one-way analysis of variance (ANOVA) was conducted to compare the district averages from the 2010 TAKS 8th grade science assessment results and the four district enrollment groups. The second phase of the study was qualitative utilizing constructivism and critical theory to identify the issues facing rural and small school administrators concerning science based curriculum and development. These themes and issues were sought through a case study method and through use of semi

Determination of metal concentrations in certified plastic reference materials after small-size autoclave and microwave-assisted digestion followed with inductively coupled plasma optical emission spectrometry

Science.gov (United States)

Lehtimäki, Esa; Väisänen, Ari

2017-01-01

The digestion methods for the determination of As, Cd, Cr, Pb, Sb, Sn and Zn concentrations in plastic samples using microwave-assisted digestion (MW-AD) and small-size autoclave digestion was developed. The certified polyethylene, polypropylene, polyvinyl chloride and acrylonitrile butadiene styrene certified reference materials were used in order to find digestion method working properly for several sample matrices. Efficiency of the digestion methods was evaluated by analyzing the residual carbon in digests by TOC analyzer. MW-AD using a mixture of 7 mL of HNO3 and 3 mL of H2O2 as a digestion solution resulted in excellent recoveries for As, Cd, Pb, Sb and Zn, and were in the range of 92-107% for all the analytes except Pb in polyethylene material. Autoclave digestion using 5 mL of concentrated HNO3 as a digestion solution resulted in similar recoveries with the exception of a higher As recovery (98%). Tin recovery resulted in low level after both MW-AD and autoclave digestion. Autoclave digestion was further developed resulting in a partially open two-step digestion process especially for the determination of Sn and Cr. The method resulted in higher recoveries of Sn and Cr (87 and 76%) but with the lower concentration of easily volatile As, Cd and Sb.

Effects of food deprivation and particle size of ground wheat on digestibility of food components in broilers fed on a pelleted diet.

Science.gov (United States)

Péron, A; Bastianelli, D; Oury, F X; Gomez, J; Carré, B

2005-04-01

The first aim of the experiment was to study the effect of wheat (Triticum aestivum) particle size on the digestibility of starch in a pelleted diet given to broilers. The second aim was to study the consequences of food deprivation before the excreta collection period (from 21 to 24 d). Wheat from a strong hardness cultivar was incorporated at 546.1 g/kg in diets. The other main ingredients were soybean meal (353.5 g/kg) and rapeseed oil (55.0 g/kg). Diets were given as pellets. The experimental design was a 2 x 2 factorial design testing two particle sizes of wheat flour and two procedures of a balance experiment (with or without food deprivation). Birds given diet C (wheat coarse grinding before pelleting) had significantly greater gizzard weight than birds fed on diet F (wheat fine grinding before pelleting). Starch digestibility value was significantly increased when birds were fed on diet F. This effect was halved by food deprivation. No significant effect of grain particle size was observed for protein and lipid digestibility values. However, food deprivation decreased apparent protein digestibility, with an effect which was more pronounced for fine than for coarse grinding. AMEN of the diet was significantly improved by fine grinding of wheat and decreased by food deprivation. However, no significant differences in growth performance were induced by differences in wheat grinding. No significant effect of grinding was observed on the water excretion:feed intake ratio. No significant difference was observed for vent score between treatments. There was over-excretion of starch in the first hours of refeeding following food deprivation.

Proteome Profiles of Digested Products of Commercial Meat Sources

Science.gov (United States)

Li, Li; Liu, Yuan; Zhou, Guanghong; Xu, Xinglian; Li, Chunbao

2017-01-01

This study was designed to characterize in vitro-digested products of proteins from four commercial meat products, including dry-cured ham, cooked ham, emulsion-type sausage, and dry-cured sausage. The samples were homogenized and incubated with pepsin and trypsin. The digestibility and particle sizes of digested products were measured. Nano-LC–MS/MS was applied to characterize peptides. The results showed the highest digestibility and the lowest particle size in dry-cured ham (P meat products. Our findings give an insight into nutritional values of different meat products. PMID:28396857

Alternative co-digestion scenarios for efficient fixed-dome reactor biomethanation processes

DEFF Research Database (Denmark)

Fotidis, Ioannis; Laranjeiro, Tiago; Angelidaki, Irini

2016-01-01

where low-tech reactors have been abandoned. Thus, the aims of this study were: a) to identify and evaluate alternative biomasses as anaerobic digestion substrates at a remote rural area site in India; b) to propose an efficient continuous biomethanation scenario for low-tech reactors; c) to assess......-digestion scenario with 45% and 13% higher energy recovery from biomasses' utilization and 69% and 25% less greenhouse gas (GHG) emissions, compared to R30 and R45, respectively. These results indicate that it is possible to operate efficiently low-tech biogas reactors with utilized biomasses as anaerobic digestion...

Digestion of Bangka monazite with sulfuric acid

International Nuclear Information System (INIS)

Riesna Prassanti

2012-01-01

Technology of Bangka monazite processing with alkaline method has been mastered by PPGN BATAN with the product in the form of RE (Rare Earth) which is contain U < 2 ppm and Th 12 - 16 ppm. Hence, as comparator, the research of Bangka monazite processing with acid method using sulfuric acid has been done. The aim of this research is to obtain the optimal condition of Bangka monazite's digestion using sulfuric acid so that all elements contained in the monazite that are U, Th, RE, PO 4 dissolved as much as possible. The research parameter's arc monazite particle's size, sulfuric acid consumption (weight ratio of monazite ore : sulfuric acid), digestion temperature, digestion time and consumption of wash water. The results showed that the optimal conditions of digestion are 250+ 325 mesh of monazite particle's size, 1 : 2.5 of weight ratio of monazite ore: sulfuric acid, 190°C of digestion temperature, 3 hours of digestion time and 8 times of weight monazite's feed of wash water with the recovery of digested U = 99.90 %, Th = 99.44 %, RE = 98.64 % and PO 4 = 99.88 %. (author)

CHARACTERIZATION OF CO-PRODUCTS OF THE PILOT DIGESTERS TO ANIMAL BIOMASS IN TUNISIA

Directory of Open Access Journals (Sweden)

Y. M’Sadak

2015-05-01

Full Text Available This work consists in evaluating the Co-products of the biomethanisation applied to the animal biomass on the level of various types of digesters (experimental I, II, III and IV, rural and industrial.This work made it possible to arise certain number of observations: The energy performances are more interesting in the case of the digesters powered with the avicolous droppings; the reduction of the polluting load as of SM is more important in the case of the industrial digester, whereas for the BDO5, it is in favor of the experimental digester II; The agronomic use of the secondary by-products proves very encouraging and powerful.

Sizing through simulation of systems for photovoltaic solar energy applied to rural electrification

International Nuclear Information System (INIS)

Rodríguez‐Borges, Ciaddy Gina; Sarmiento‐Sera, Antonio

2011-01-01

The present work is based on the sizing method by means of simulation of the photovoltaic systems energy behavior, applied to rural electrification in regions far from the electric net. The denomination of infra/over sized systems is made and a requested analysis of one particular case is exposed, where it is considered two energy options of different qualities of electric service and the economic valuation of each option is requested, with its corresponding argument. The quality level is established with the fault index in the electricity service for energy lack in the batteries, besides the quantity of energy autonomy days of the system. As conclusions, in infra-sizing conditions systems, and with established quality level of service, multiple sizing solutions exist, and under certain conditions, not always the systems with more quality level, are those of more cost, as well as the presence of a minimum cost in the sizing can be obtained by simulation methods. (author)

The Dilemma and Way-Out of Urban and Rural Planning Management in China’s Small and Medium-Sized Cities

Institute of Scientific and Technical Information of China (English)

Dawei; WANG; Yandong; WANG

2014-01-01

In China, for small and medium-sized cities, urban and rural planning management should play an important role during the process of urbanization. However, it failed to do that in reality due to a series of limits, such as local fiscal deficiency, scarce human resources, incomplete management systems, historic planning defects, inadequate supervisions, and imperfect regulations, etc. This paper made a comprehensive analysis on the dilemma of urban and rural planning management in China’s small and medium-sized cities and the interests and status of the government, enterprises and public in space resource allocation and put forward the methods to improve the quality of planning management in China’s small and medium-sized cities from the view of systems and mechanisms.

Improved design of anaerobic digesters for household biogas production in indonesia: one cow, one digester, and one hour of cooking per day.

Science.gov (United States)

Usack, Joseph G; Wiratni, Wiratni; Angenent, Largus T

2014-01-01

A government-sponsored initiative in Indonesia to design and implement low-cost anaerobic digestion systems resulted in 21 full-scale systems with the aim to satisfy the cooking fuel demands of rural households owning at least one cow. The full-scale design consisted of a 0.3 m diameter PVC pipe, which was operated as a conventional plug-flow system. The system generated enough methane to power a cooking stove for ∼ 1 h. However, eventual clogging from solids accumulation inside the bioreactor proved to be a major drawback. Here, we improved the digester configuration to remedy clogging while maintaining system performance. Controlled experiments were performed using four 9-L laboratory-scale digesters operated at a temperature of 27 ± 1 °C, a volatile solids loading rate of 2.0 g VS · L(-1) · day(-1), and a 21-day hydraulic retention time. Two of the digesters were replicates of the original design (control digesters), while the other two digesters included internal mixing or effluent recycle (experimental digesters). The performance of each digester was compared based on methane yields, VS removal efficiencies, and steady-state solids concentrations during an operating period of 311 days. Statistical analyses revealed that internal mixing and effluent recycling resulted in reduced solids accumulation compared to the controls without diminishing methane yields or solids removal efficiencies.

Improved Design of Anaerobic Digesters for Household Biogas Production in Indonesia: One Cow, One Digester, and One Hour of Cooking per Day

Directory of Open Access Journals (Sweden)

Joseph G. Usack

2014-01-01

Full Text Available A government-sponsored initiative in Indonesia to design and implement low-cost anaerobic digestion systems resulted in 21 full-scale systems with the aim to satisfy the cooking fuel demands of rural households owning at least one cow. The full-scale design consisted of a 0.3 m diameter PVC pipe, which was operated as a conventional plug-flow system. The system generated enough methane to power a cooking stove for ∼1 h. However, eventual clogging from solids accumulation inside the bioreactor proved to be a major drawback. Here, we improved the digester configuration to remedy clogging while maintaining system performance. Controlled experiments were performed using four 9-L laboratory-scale digesters operated at a temperature of 27±1°C, a volatile solids loading rate of 2.0 g VS·L−1·day−1, and a 21-day hydraulic retention time. Two of the digesters were replicates of the original design (control digesters, while the other two digesters included internal mixing or effluent recycle (experimental digesters. The performance of each digester was compared based on methane yields, VS removal efficiencies, and steady-state solids concentrations during an operating period of 311 days. Statistical analyses revealed that internal mixing and effluent recycling resulted in reduced solids accumulation compared to the controls without diminishing methane yields or solids removal efficiencies.

Co-digestion of rice straw and cow dung to supply cooking fuel and fertilizers in rural India: Impact on human health, resource flows and climate change.

Science.gov (United States)

Sfez, Sophie; De Meester, Steven; Dewulf, Jo

2017-12-31

Anaerobic digestion of cow dung with new feedstock such as crop residues to increase the biogas potential is an option to help overcoming several issues faced by India. Anaerobic digestion provides biogas that can replace biomass cooking fuels and reduce indoor air pollution. It also provides digestate, a fertilizer that can contribute to compensate nutrient shortage on agricultural land. Moreover, it avoids the burning of rice straw in the fields which contributes to air pollution in India and climate change globally. Not only the technical and economical feasibility but also the environmental sustainability of such systems needs to be assessed. The potential effects of implementing community digesters co-digesting cow dung and rice straw on carbon and nutrients flows, human health, resource efficiency and climate change are analyzed by conducting a Substance Flow Analysis and a Life Cycle Assessment. The implementation of the technology is considered at the level of the state of Chhattisgarh. Implementing this scenario reduces the dependency of the rural community to nitrogen and phosphorus from synthetic fertilizers only by 0.1 and 1.6%, respectively, but the dependency of farmers to potassium from synthetic fertilizers by 31%. The prospective scenario returns more organic carbon to agricultural land and thus has a potential positive effect on soil quality. The implementation of the prospective scenario can reduce the health impact of the local population by 48%, increase the resource efficiency of the system by 60% and lower the impact on climate change by 13%. This study highlights the large potential of anaerobic digestion to overcome the aforementioned issues faced by India. It demonstrates the need to couple local and global assessments and to conduct analyses at the substance level to assess the sustainability of such systems. Copyright © 2017 Elsevier B.V. All rights reserved.

Blood Parameters, Digestive Organ Size and Intestinal Microflora of Broiler Chicks Fed Sorghum as Partial Substitute of Corn

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Anca GHEORGHE

2017-11-01

Full Text Available A study was conducted to evaluate the effects of dietary white sorghum (WS, as partial substitute of corn on blood parameters, digestive organ size and intestinal microflora of broilers at 35 d. Cobb 500 broilers (n=400, assigned to 2 groups, were fed with isocaloric and isonitrogenous corn-soybean meal control diets (C or corn-WS-soybean meal diets (WS, where corn was partially replaced (50% with WS. At 35 d, sixteen broilers per group were selected for blood sampling, gastrointestinal (GIT measurements, digesta pH and ileum microflora analysis. There was no effect (P>0.05 of the dietary WS inclusion on blood biochemistry parameters, GIT development and digesta pH of broilers. In our study, dietary WS significantly reduced the ileal population of Enterobacteriaceae (-1.38%; P<0.0001 and E. coli (-1.16%; P=0.020, and increased the Lactobacillus spp. (+1.07%; P=0.014 compared with the C diet. In conclusion, feeding white sorghum, as partial substitute of corn in broiler diets, did not affect blood parameters, digestive organ size and digesta pH, that support the obtained performance. In addition, sorghum had a positive effect of the ileal microflora increasing the beneficial bacterial Lactobacillus spp.

Supplementing energy demand of rural households in Bangladesh through appropriate biogas technology

DEFF Research Database (Denmark)

Ashekuzzaman, S.M.; Badruzzaman, A.B.M.; Rafiqul Hoque, A.T.M.

2010-01-01

This paper has sought to show the potential of energy recovery from rurally available agro and household organic wastes and thus, the possible impact on supplementing energy demand, reducing deforestation, and replacing fossil fuel as well as avoided greenhouse gases. Results show that co......-digestion of a wide range of manure, crop residues and household wastes with cow manure was successful to produce increased gas yield than what would be if cow dung is digested separately and the energy value from this can supplement 57–79% of the rural energy demand, depending on the methane yield from organic waste...

Growth performance and total tract nutrient digestion for Holstein heifers limit-fed diets high in distillers grains with different forage particle sizes

Science.gov (United States)

This study evaluated dairy heifer growth performance and total tract nutrient digestion when fed diets high in dried distillers grains with solubles (DDGS) with different forage particle size. An 8-wk randomized complete block design study was conducted utilizing twenty-two Holstein heifers (123 ±...

Open vessel microwave digestion of food matrices (T6)

International Nuclear Information System (INIS)

Rhodes, L.; LeBlanc, G.

2002-01-01

Full text: Advancements in the field of open vessel microwave digestion continue to provide solutions for industries requiring acid digestion of large sample sizes. Those interesting in digesting food matrices are particularly interested in working with large amounts of sample and then diluting small final volumes. This paper will show the advantages of instantaneous regent addition and post-digestion evaporation when performing an open vessel digestion and evaporation methods for various food matrices will be presented along with analyte recovery data. (author)

Waste treatment and energy production from small-scale wastewater digesters.

Science.gov (United States)

Lansing, Stephanie; Maile-Moskowitz, Ayella; Eaton, Alexander

2017-12-01

Three tubular anaerobic digestion (AD) systems were installed in Haiti to treat black water (toilet-based wastewater), including a three cell 36m 3 clinic digester (CD), a two cell 2m 3 hotel digester (HD), and a three-cell 3m 3 farm digester (FD) for worker use. During digestion, total coliforms were reduced by 99.1%, E. coli by 98.5%, and chemical oxygen demand (COD) by 93.6%. Nutrients in the effluent averaged 99.4mg/L NH 4 + and 10.6mg/L PO 4 2- , producing an effective organic fertilizer. Average biogas production in CD was 108L/d, with 65.4% CH 4 . Survey participants (n=573) were willing to pay $0.10-0.30 per use for sanitation facilities. Seventy-two percent of the rural population surveyed in Cange, Haiti lacked access to improved sanitation due to financial constraints. The economic analysis calculated an investment cost for a shared toilet AD systems of $16-$47 (USD) per person based on daily use at design capacity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Canonical correlation analysis of infant's size at birth and maternal factors: a study in rural northwest Bangladesh.

Science.gov (United States)

Kabir, Alamgir; Merrill, Rebecca D; Shamim, Abu Ahmed; Klemn, Rolf D W; Labrique, Alain B; Christian, Parul; West, Keith P; Nasser, Mohammed

2014-01-01

This analysis was conducted to explore the association between 5 birth size measurements (weight, length and head, chest and mid-upper arm [MUAC] circumferences) as dependent variables and 10 maternal factors as independent variables using canonical correlation analysis (CCA). CCA considers simultaneously sets of dependent and independent variables and, thus, generates a substantially reduced type 1 error. Data were from women delivering a singleton live birth (n = 14,506) while participating in a double-masked, cluster-randomized, placebo-controlled maternal vitamin A or β-carotene supplementation trial in rural Bangladesh. The first canonical correlation was 0.42 (P<0.001), demonstrating a moderate positive correlation mainly between the 5 birth size measurements and 5 maternal factors (preterm delivery, early pregnancy MUAC, infant sex, age and parity). A significant interaction between infant sex and preterm delivery on birth size was also revealed from the score plot. Thirteen percent of birth size variability was explained by the composite score of the maternal factors (Redundancy, RY/X = 0.131). Given an ability to accommodate numerous relationships and reduce complexities of multiple comparisons, CCA identified the 5 maternal variables able to predict birth size in this rural Bangladesh setting. CCA may offer an efficient, practical and inclusive approach to assessing the association between two sets of variables, addressing the innate complexity of interactions.

Canonical correlation analysis of infant's size at birth and maternal factors: a study in rural northwest Bangladesh.

Directory of Open Access Journals (Sweden)

Alamgir Kabir

Full Text Available This analysis was conducted to explore the association between 5 birth size measurements (weight, length and head, chest and mid-upper arm [MUAC] circumferences as dependent variables and 10 maternal factors as independent variables using canonical correlation analysis (CCA. CCA considers simultaneously sets of dependent and independent variables and, thus, generates a substantially reduced type 1 error. Data were from women delivering a singleton live birth (n = 14,506 while participating in a double-masked, cluster-randomized, placebo-controlled maternal vitamin A or β-carotene supplementation trial in rural Bangladesh. The first canonical correlation was 0.42 (P<0.001, demonstrating a moderate positive correlation mainly between the 5 birth size measurements and 5 maternal factors (preterm delivery, early pregnancy MUAC, infant sex, age and parity. A significant interaction between infant sex and preterm delivery on birth size was also revealed from the score plot. Thirteen percent of birth size variability was explained by the composite score of the maternal factors (Redundancy, RY/X = 0.131. Given an ability to accommodate numerous relationships and reduce complexities of multiple comparisons, CCA identified the 5 maternal variables able to predict birth size in this rural Bangladesh setting. CCA may offer an efficient, practical and inclusive approach to assessing the association between two sets of variables, addressing the innate complexity of interactions.

Cluster analysis of rural, urban, and curbside atmospheric particle size data.

Science.gov (United States)

Beddows, David C S; Dall'Osto, Manuel; Harrison, Roy M

2009-07-01

Particle size is a key determinant of the hazard posed by airborne particles. Continuous multivariate particle size data have been collected using aerosol particle size spectrometers sited at four locations within the UK: Harwell (Oxfordshire); Regents Park (London); British Telecom Tower (London); and Marylebone Road (London). These data have been analyzed using k-means cluster analysis, deduced to be the preferred cluster analysis technique, selected from an option of four partitional cluster packages, namelythe following: Fuzzy; k-means; k-median; and Model-Based clustering. Using cluster validation indices k-means clustering was shown to produce clusters with the smallest size, furthest separation, and importantly the highest degree of similarity between the elements within each partition. Using k-means clustering, the complexity of the data set is reduced allowing characterization of the data according to the temporal and spatial trends of the clusters. At Harwell, the rural background measurement site, the cluster analysis showed that the spectra may be differentiated by their modal-diameters and average temporal trends showing either high counts during the day-time or night-time hours. Likewise for the urban sites, the cluster analysis differentiated the spectra into a small number of size distributions according their modal-diameter, the location of the measurement site, and time of day. The responsible aerosol emission, formation, and dynamic processes can be inferred according to the cluster characteristics and correlation to concurrently measured meteorological, gas phase, and particle phase measurements.

Performance of dry anaerobic technology in the co-digestion of rural organic solid wastes in China

International Nuclear Information System (INIS)

Yang, Tianxue; Li, Yingjun; Gao, Jixi; Huang, Caihong; Chen, Bin; Zhang, Lieyu; Wang, Xiaowei; Zhao, Ying; Xi, Beidou; Li, Xiang

2015-01-01

The dry anaerobic co-digestion of LW (livestock waste), OFHW (organic fraction of household waste), and AR (agricultural residue) was evaluated in terms of pH stability, organic removal rate, and methane yield. The total quantity of the solids involved in the digestion was adjusted to 25%. All the reactors were inoculated by 20% (in dry weight) of the municipal sludge. The dynamic changes in the pH values of the LW-AR-OFHW mixture co-digestions underwent four stages and differed from those of wet anaerobic digestion. The decrease in VS (volatile solids), volume, and weight of the LW-AR-OFHW mixtures was higher than those in AR and OFHW. The VS, volume, and weight reductions in LW-AR-OFHW co-digestion were 54.7%, 82.2%, and 72.7%, respectively. However, the VS, volume, and weight reductions in AR were only 11.1%, 20.5%, and 19.8%, respectively, and those in OFHW were only 27.4%, 45.0%, and 40.9%, respectively. The LW-AR-OFHW mixture co-digestions enhanced the methane production of the co-digester (256 m 3 /ton VS), whereas AR and OFHW produced only 12 and 93 m 3 methane/ton VS, respectively. - Highlights: • The pH values dynamic of LW-AR-OFHW differed from wet anaerobic digestion. • The degradation effect of LW-AR-OFHW was better than those of AR and OFHW. • The LW-AR-OFHW mixture co-digestions enhanced the methane production.

Effects of corn-based diet starch content and corn particle size on lactation performance, digestibility, and bacterial protein flow in dairy cows.

Science.gov (United States)

Fredin, S M; Ferraretto, L F; Akins, M S; Bertics, S J; Shaver, R D

2015-01-01

An experiment was conducted to determine the effects of dietary starch content in corn-based diets and corn particle size on lactation performance, nutrient digestibility, and bacterial protein flow in dairy cows using the omasal and reticular sampling technique. Eight ruminally cannulated lactating multiparous Holstein cows were used in a replicated 4×4 Latin square design with a 2×2 factorial arrangement of treatments. Treatments were fine (FG; mean particle size=552µm) and coarse (CG; 1,270µm) ground dry shelled corn in normal- (NS) and reduced- (RS) starch diets fed as total mixed rations. The NS and RS rations contained 27 and 18% starch (dry matter basis), respectively, and were formulated by partially replacing corn with soy hull pellets. Mean dry matter intake was unaffected by treatment (23.2kg/d). Cows fed NS diets produced 1.9kg/d more milk and 0.06kg/d more milk protein compared with cows fed RS diets. Cows fed NSFG and RSCG diets produced more fat-corrected milk than did cows fed NSCG and RSFG diets. Milk urea concentration was decreased for cows fed NS diets (12.4mg/dL) compared with RS diets (13.5mg/dL). Ruminal digestibility of neutral detergent fiber (NDF; % of NDF intake) determined by the omasal sampling technique was increased in cows fed RS diets compared with NS diets (43.4 vs. 34.9%), and total-tract digestibility of NDF (% of NDF intake) was increased in cows fed RS diets compared with those fed NS diets (50.1 vs. 43.1%). Ruminal digestibility of starch (% of starch intake) determined by the omasal sampling technique was greater in cows fed NS diets compared with those fed RS diets (85.6 vs. 81.6%). Total-tract starch digestion was increased in cows fed RS diets compared with those fed NS diets (96.9 vs. 94.6%) and in cows fed FG diets compared with those fed CG diets (98.0 vs. 93.5%). Bacterial protein flow was unaffected by treatment. The omasal and reticular sampling techniques resulted in similar treatment effects for nutrient flow

The Physical State of Emulsified Edible Oil Modulates Its in Vitro Digestion.

Science.gov (United States)

Guo, Qing; Bellissimo, Nick; Rousseau, Dérick

2017-10-18

Emulsified lipid digestion was tailored by manipulating the physical state of dispersed oil droplets in whey protein stabilized oil-in-water (O/W) emulsions, where the oil phase consisted of one of five ratios of soybean oil (SO) and fully hydrogenated soybean oil (FHSO). The evolution in particle size distribution, structural changes during oral, gastric, and intestinal digestion, and free fatty acid release during intestinal digestion were all investigated. Irrespective of the physical state and structure of the dispersed oil/fat, all emulsions were stable against droplet size increases during oral digestion. During gastric digestion, the 50:50 SO:FHSO emulsion was more stable against physical breakdown than any other emulsion. All emulsions underwent flocculation and coalescence or partial coalescence upon intestinal digestion, with the SO emulsion being hydrolyzed the most rapidly. The melting point of all emulsions containing FHSO was above 37 °C, with the presence of solid fat within the dispersed oil droplets greatly limiting lipolysis. Fat crystal polymorph and nanoplatelet size did not play an important role in the rate and extent of lipid digestion. Free fatty acid release modeled by the Weibull distribution function showed that the rate of lipid digestion (κ) decreased with increasing solid fat content, and followed an exponential relationship (R 2 = 0.95). Overall, lipid digestion was heavily altered by the physical state of the dispersed oil phase within O/W emulsions.

Effects of particle size and adaptation duration on the digestible and metabolizable energy contents and digestibility of various chemical constituents in wheat for finishing pigs determined by the direct or indirect method.

Science.gov (United States)

Fan, Yuanfang; Guo, Panpan; Yang, Yuyuan; Xia, Tian; Liu, Ling; Ma, Yongxi

2017-04-01

This experiment was conducted as a 3×2×2 factorial design to examine the effects of particle size (mean particle size of 331, 640, or 862 μm), evaluation method (direct vs indirect method) and adaptation duration (7 or 26 days) on the energy content and the apparent total tract digestibility (ATTD) of various chemical components in wheat when fed to finishing pigs. Forty-two barrows (Duroc×Landrace×Yorkshire) with an initial body weight of 63.0±0.8 kg were individually placed in metabolic cages and randomly allotted to 1 of 7 diets with 6 pigs fed each diet. For the indirect method, the pigs were fed either a corn-soybean meal based basal diet or diets in which 38.94% of the basal diet was substituted by wheat of the different particle sizes. In the direct method, the diets contained 97.34% wheat with the different particle sizes. For both the direct and indirect methods, the pigs were adapted to their diets for either 7 or 26 days. A reduction in particle size linearly increased the digestible energy (DE) and metabolizable energy (ME) contents as well as the ATTD of gross energy, crude protein, organic matter, ether extract (EE) and acid detergent fiber (ADF) (penergy, crude protein, dry matter and organic matter were higher (pdirect method, but the ATTD of ADF, EE, and neutral detergent fiber were higher when determined by the indirect method (pdirect method but quadratic equations (p = 0.073 and p = 0.088, respectively) about ATTD of ADF and EE when determined by the indirect method. Decreasing particle size can improve the DE and ME contents of wheat; both of the direct and indirect methods of evaluation are suitable for evaluating the DE and ME contents of wheat with different particle sizes; and an adaptation duration of 7 d is sufficient to evaluate DE and ME contents of wheat in finishing pigs.

Characterization of co-products of the pilot digesters to animal ...

African Journals Online (AJOL)

This work consists in evaluating the Co-products of the biomethanisation applied to the animal biomass on the level of various types of digesters (experimental I, II, III and IV, rural and industrial). This work made it possible to arise certain number of observations: The energy performances are more interesting in the case of ...

The effects of particle size, milling method, and thermal treatment of feed on performance, apparent ileal digestibility, and pH of the digesta in laying hens.

Science.gov (United States)

Ruhnke, Isabelle; Röhe, Ilen; Krämer, Carolin; Goodarzi Boroojeni, Farshad; Knorr, Fanny; Mader, Anneluise; Schulze, Erin; Hafeez, Abdul; Neumann, Konrad; Löwe, Rainer; Zentek, Jürgen

2015-04-01

Various milling methods result in different particle size distributions and, in combination with mash and thermal treatment (expandate) of the feed, may have an impact on nutrient digestibility, pH of the digesta and subsequently the performance of an animal. Since this aspect has not been widely considered in laying hens, the objective of the present study was to investigate the effects of milling method, expansion, and particle size of feed on performance, apparent ileal nutrient digestibility, and pH of digesta in laying hens. Twelve variants of the same diet were produced. Four different milling techniques (hammer mill, roller mill, disc mill, and wedge-shaped disc mill) were used to grind the feed cereals. Coarse feed was obtained from all four mills. Additionally, fine feed was obtained from the hammer mill and the roller mill. Each of the six feed variants was offered as mash or expandate, resulting in a total of 12 treatments. The duration of the experimental period was 21 days. A total of 576 layers, each 19 weeks of age, were used in eight replicates. The statistical analysis for the four milling methods and two thermal treatments was performed using a 4×2 factorial arrangement. The effect of particle size was investigated using a 2×2×2 factorial arrangement including the coarse and fine particle sizes that were produced with the hammer mill and the roller mill as well as the mash and expandate. The animal performance and the pH of the digesta were not affected by the treatments. Ileal digestibility of starch was significantly improved by feeding mash compared to expandate (P=0.013) and by feeding coarse compared to fine feed (P=0.028). Based on this study, the tested milling methods can be used for the production of feed for laying hens without affecting performance and digestibility of nutrients. © 2015 Poultry Science Association Inc.

Economic viability of anaerobic digestion

Energy Technology Data Exchange (ETDEWEB)

Wellinger, A. [INFOENERGIE, Ettenhausen (Switzerland)

1996-01-01

The industrial application of anaerobic digestion is a relatively new, yet proven waste treatment technology. Anaerobic digestion reduces and upgrades organic waste, and is a good way to control air pollution as it reduces methane and nitrous gas emissions. For environmental and energy considerations, anaerobic digestion is a nearly perfect waste treatment process. However, its economic viability is still in question. A number of parameters - type of waste (solid or liquid), digester system, facility size, product quality and end use, environmental requirements, cost of alternative treatments (including labor), and interest rates - define the investment and operating costs of an anaerobic digestion facility. Therefore, identical facilities that treat the same amount and type of waste may, depending on location, legislation, and end product characteristics, reveal radically different costs. A good approach for evaluating the economics of anaerobic digestion is to compare it to treatment techniques such as aeration or conventional sewage treatment (for industrial wastewater), or composting and incineration (for solid organic waste). For example, the cost (per ton of waste) of in-vessel composting with biofilters is somewhat higher than that of anaerobic digestion, but the investment costs 1 1/2 to 2 times more than either composting or anaerobic digestion. Two distinct advantages of anaerobic digestion are: (1) it requires less land than either composting or incinerating, which translates into lower costs and milder environmental and community impacts (especially in densely populated areas); and (2) it produces net energy, which can be used to operate the facility or sold to nearby industries.

Dynamic effect of total solid content, low substrate/inoculum ratio and particle size on solid-state anaerobic digestion.

Science.gov (United States)

Motte, J-C; Escudié, R; Bernet, N; Delgenes, J-P; Steyer, J-P; Dumas, C

2013-09-01

Among all the process parameters of solid-state anaerobic digestion (SS-AD), total solid content (TS), inoculation (S/X ratio) and size of the organic solid particles can be optimized to improve methane yield and process stability. To evaluate the effects of each parameter and their interactions on methane production, a three level Box-Behnken experimental design was implemented in SS-AD batch tests degrading wheat straw by adjusting: TS content from 15% to 25%, S/X ratio (in volatile solids) between 28 and 47 and particle size with a mean diameter ranging from 0.1 to 1.4mm. A dynamic analysis of the methane production indicates that the S/X ratio has only an effect during the start-up phase of the SS-AD. During the growing phase, TS content becomes the main parameter governing the methane production and its strong interaction with the particle size suggests the important role of water compartmentation on SS-AD. Copyright © 2013 Elsevier Ltd. All rights reserved.

Sizing of integrated energy systems in rural areas; Dimensionamento de sistemas integrados de energia em areas rurais

Energy Technology Data Exchange (ETDEWEB)

Nogueira, Carlos Eduardo Camargo [Universidade Estadual do Oeste do Parana (UNIOESTE), Cascavel, PR (Brazil). Centro de Ciencias Exatas e Tecnologicas], e-mail: cecn@correios.net.br; Zuern, Hans Helmut [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Energia Eletrica], e-mail: hans@labspot.ufsc.br

2004-07-01

The purpose of this work was to develop a new model for sizing integrated energy systems in rural areas, based on simulation techniques and linear programming, producing a system with minimum cost and high reliability level. The used reliability level was the loss of power supply probability (LPSP), for periods of consecutive hours. With the developed model, many simulations are accomplished with the parameters and sizing variables, making possible the analysis of different scenarios for the optimized energy systems. (author)

Diets high in resistent starch and arabinoxylan modulate digestion processes and SCFA pool size in the large intestine and faecal microbial composition in pigs

DEFF Research Database (Denmark)

Nielsen, Tina Skau; Lærke, Helle Nygaard; Theil, Peter Kappel

2014-01-01

The effects of a high level of dietary fibre (DF) either as arabinoxylan (AX) or resistant starch (RS) on digestion processes, SCFA concentration and pool size in various intestinal segments and on the microbial composition in the faeces were studied in a model experiment with pigs. A total...... resulted in a 3- to 5-fold higher pool size of butyrate compared with WSD feeding, with the RSD being intermediate (P microbial composition towards butyrogenic...

Feeding behavior and digestive physiology in sea cucumber Apostichopus japonicus.

Science.gov (United States)

Sun, Jiamin; Zhang, Libin; Pan, Yang; Lin, Chenggang; Wang, Fang; Kan, Rentao; Yang, Hongsheng

2015-02-01

The feeding behavior and digestive physiology of the sea cucumber, Apostichopus japonicus are not well understood. A better understanding may provide useful information for the development of the aquaculture of this species. In this article the tentacle locomotion, feeding rhythms, ingestion rate (IR), feces production rate (FPR) and digestive enzyme activities were studied in three size groups (small, medium and large) of sea cucumber under a 12h light/12h dark cycle. Frame-by-frame video analysis revealed that all size groups had similar feeding strategies using a grasping motion to pick up sediment particles. The tentacle insertion rates of the large size group were significantly faster than those of the small and medium-sized groups (Psea cucumber were nocturnal and their feeding peaks occurred at 02:00-04:00. The medium and large-sized groups also had a second feeding peak during the day. Both IR and FPR in all groups were significantly higher at night than those during the daytime (P<0.05). Additionally, the peak activities of digestive enzymes were 2-4h earlier than the peak of feeding. Taken together, these results demonstrated that the light/dark cycle was a powerful environment factor that influenced biological rhythms of A. japonicus, which had the ability to optimize the digestive processes for a forthcoming ingestion. Copyright © 2014 Elsevier Inc. All rights reserved.

Potential impact of inorganic nanoparticles on macronutrient digestion: titanium dioxide nanoparticles slightly reduce lipid digestion under simulated gastrointestinal conditions.

Science.gov (United States)

Li, Qian; Li, Ti; Liu, Chengmei; DeLoid, Glen; Pyrgiotakis, Georgios; Demokritou, Philip; Zhang, Ruojie; Xiao, Hang; McClements, David Julian

Titanium dioxide (TiO 2 ) particles are used in some food products to alter their optical properties, such as whiteness or brightness. These additives typically contain a population of TiO 2 nanoparticles (d digestion through two physicochemical mechanisms: (i) a fraction of the lipase adsorbs to TiO 2 particle surfaces, thereby reducing the amount available to hydrolyze lipid droplets; (ii) some TiO 2 particles adsorb to the surfaces of lipid droplets, thereby reducing the lipid surface area exposed to lipase. The importance of these mechanisms was tested by passing protein-coated lipid droplets (2%, w/w) through the simulated GIT in the absence and presence of TiO 2 (0.5%, w/w) nanoparticles (18 nm) and fine particles (167 nm). Changes in particle characteristics (size, organization, and charge) and lipid digestion were then measured. Both TiO 2 nanoparticles and fine particles had little impact on the aggregation state and charge of the lipid droplets in the different GIT regions, as well as on the rate and extent of lipid digestion. This suggests that the theoretically predicted impact of particle size on lipid digestion was not seen in practice.

Mini-Digest of Education Statistics, 2010. NCES 2011-016

Science.gov (United States)

Snyder, Thomas D.

2011-01-01

This pocket-sized compilation of statistical information covers prekindergarten through graduate school to describe the current American education scene. The "Mini-Digest" is designed as an easy reference for materials found in detail in the "Digest of Education Statistics". These volumes include selections of data from many…

Air pollution and inhalation exposure to particulate matter of different sizes in rural households using improved stoves in central China.

Science.gov (United States)

Liu, Weijian; Shen, Guofeng; Chen, Yuanchen; Shen, Huizhong; Huang, Ye; Li, Tongchao; Wang, Yilong; Fu, Xiaofang; Tao, Shu; Liu, Wenxin; Huang-Fu, Yibo; Zhang, Weihao; Xue, Chunyu; Liu, Guangqing; Wu, Fuyong; Wong, Minghung

2018-01-01

Household air pollution is considered to be among the top environmental risks in China. To examine the performance of improved stoves for reduction of indoor particulate matter (PM) emission and exposure in rural households, individual inhalation exposure to size-resolved PM was investigated using personal portable samplers carried by residents using wood gasifier stoves or improved coal stoves in a rural county in Central China. Concentrations of PM with different sizes in stationary indoor and outdoor air were also monitored at paired sites. The stationary concentrations of size-resolved PM in indoor air were greater than those in outdoor air, especially finer particles PM 0.25 . The daily averaged exposure concentrations of PM 0.25 , PM 1.0 , PM 2.5 and total suspended particle for all the surveyed residents were 74.4±41.1, 159.3±74.3, 176.7±78.1 and 217.9±78.1μg/m 3 , respectively. Even using the improved stoves, the individual exposure to indoor PM far exceeded the air quality guideline by WHO at 25μg/m 3 . Submicron particles PM 1.0 were the dominant PM fraction for personal exposure and indoor and outdoor air. Personal exposure exhibited a closer correlation with indoor PM concentrations than that for outdoor concentrations. Both inhalation exposure and indoor air PM concentrations in the rural households with gasifier firewood stoves were evidently lower than the reported results using traditional firewood stoves. However, local governments in the studied rural areas should exercise caution when widely and hastily promoting gasifier firewood stoves in place of improved coal stoves, due to the higher PM levels in indoor and outdoor air and personal inhaled exposure. Copyright © 2017. Published by Elsevier B.V.

Mini-Digest of Education Statistics, 2008. NCES 2009-021

Science.gov (United States)

Snyder, Thomas D.

2009-01-01

This publication is the 14th edition of the "Mini-Digest of Education Statistics," a pocket-sized compilation of statistical information covering the broad field of American education from kindergarten through graduate school. The "Mini-Digest" is designed as an easy reference for materials found in much greater detail in the…

Casemix funding in rural NSW: exploring the effects of isolation and size.

Science.gov (United States)

Hindle, D; Frances, M; Pearse, J

1998-01-01

The New South Wales Department of Health (NSW Health) wishes to make appropriate use of casemix data as inputs to the determination of funding levels for small rural hospitals. However, other factors such as hospital size and degree of isolation might need to be taken into account. The study reported here involved correlation of actual expenditures with those predicted by use of a casemix model alone, across 105 small public hospitals in the State. We then explored the extent to which the correlation could be increased by the addition of distance and isolation variables. It was found that actual costs were highly correlated with those predicted from the casemix data alone, and that the correlation increased when both the distance and the size variables were introduced. However, contrary to expectations, reduced size was associated with reduced costs, and reduced isolation was associated with increased costs. It was concluded that, while the predicted relationships may be present, they are likely to be relatively weak and are probably being masked by other factors not present in the model. In particular, it seems likely that there are variations in severity within the acute admitted patient category which are not fully explained by the casemix instrument used in this study (the DRG classification). We suggest that other terms be introduced to control for this possibility before any further attempt is made to test whether size and distance factors can be identified which work in the expected direction.

In vitro digestibility of lucerne hay using bag method

Directory of Open Access Journals (Sweden)

constantin gavan

2013-10-01

Full Text Available A filter bag method was used for estimating apparent dry matter (DM digestibility, apparent digestible organic matter in DM, true DM digestibility, true digestible organic matter in DM and Digestibility of neutral detergent fibre. The forage sample analysed comprised tree plant parts (whole, leaf and stem of alfalfa (Medicago sativa, one degree of particle breakdown (1 mm sieve size at miliing and two field replicates at Agricultural Research and Developement Station (ARDS Șimnic-Craiova. Rumen fluid was used from two cannulated dairy cows. The use of filter bags can give acceptable results for the in vitro digestibility of forages. The escape of soluble matter from bags with samples high in solubles could influence the microbial population and hence increase cell wall degradation in bags with samples low in soluble matter, if  all are in the same incubation vessel.

The progress and prospects of rural biogas production in China

International Nuclear Information System (INIS)

Chen, Ling; Zhao, Lixin; Ren, Changshan; Wang, Fei

2012-01-01

Biogas production is an important aspect of China's energy strategy. After decades’ application and research, China biogas has achieved considerable accomplishments. This study presents the progress and prospect of biogas technologies and industry in China. Two biogas patterns exist in China, that is, household-scaled digester for scattered farmers and biogas plant for centralized biogas production. Household-scaled digester which is simple and practical has been widely used and fully developed. Biogas plants have being sprung up with different materials, process and biogas utilization technologies. By the end of 2010, 38.51 million household-scaled digesters, and 27,436 large- and medium-scaled biogas plants for agricultural wastes were built. The calculation result of biogas potential from agricultural wastes shows that those used raw materials account for only 1.90% of the total availability. Chinese government promulgated several laws and policies, and gave financial supports to promote the development of biogas. However, some problems such as inferior equipment technology, imperfect policy incentive hamper its wide application and promotion. With the rapid development of economy and the improvement of rural living condition, China biogas industry is expected to advance toward orientation of scalization, industrialization and commercialization. - Highlights: ► Developing progress of biogas production in China is evaluated comprehensively. ► Status of biogas industrialization is estimated. ► New problems which occurred during rural biogas construction were analyzed. ► Biogas production potentials from agricultural wastes in China were calculated. ► Prospect of China rural biogas is expected.

Experimental determination of submicron aerosol dry deposition velocity onto rural canopies: influence of aerosol size, of micro meteorological parameters and of the substrate

International Nuclear Information System (INIS)

Damay, P.

2010-04-01

To evaluate the impact of accidental or chronic pollutant releases on ecosystems, we must study the dry deposition of aerosols in rural areas. The lack of experimental data on the dry deposition velocity of particle sizes below 1 μm over rural environments leads to uncertainties regarding models and differences between them, which exceed one order of magnitude. The aim of this study is to develop a method, especially using an Electrical Low Pressure Impactor (Outdoor ELPIDEKATI) to determine aerosol dry deposition velocities (Vd) over rural areas through experimental measurements. This method is based on eddy covariance flux calculation and spectral analysis correction. Dry deposition velocities were obtained for atmospheric aerosols sizing from 7 nm to 2 μm, in the South-West of France on a flat terrain under varied meteorological conditions and varied substrates (maize, grass and earth). Vd was analysed as a function of the particle diameters, and the impact of micro meteorological parameters was studied. (author)

Is There A Rural-Urban Technology Gap? Results of the ERS Rural Manufacturing Survey

OpenAIRE

Gale, H. Frederick, Jr.

1997-01-01

Advanced technology use is less prevalent in rural than in urban manufacturing plants, but plants of comparable size in the same industry use about the same level of technology, regardless of urban/rural location. The rural gap comes about because the mix of rural industries is more heavily weighted with "low-technology" industries. Both rural and urban businesses rate inadequate worker skills as the most important barrier to use of new production technologies and management practices, while ...

A comparative study of factors influencing decisions on desired family size among married men and women in Bokkos, a rural local government area in Plateau state.

Science.gov (United States)

Kahansim, Makshwar L; Hadejia, Idris S; Sambo, Mohammed N

2013-03-01

The total fertility rate of Nigerian women has remained high at 5.7. This is even higher for women in rural areas. Men and women in rural areas desire more children than those in urban areas. This study was aimed at describing and comparing the factors that influence family size decisions among men and women in Bokkos, a rural Local Government Area in Plateau state, Nigeria. A cross sectional descriptive comparative study was used. Data was collected using structured interviewer administered questionnaires. Seventy two percent of women and 83.6% of men who desire to have 1-4 children had at least a secondary school education. Close to seventy percent of both men and women would have fewer children if they are certain of their survival to adulthood. Over 50% of the respondents believe that the husbands should have the final say on family size decisions. Preference for male children influences decisions on family size among men and women in the study population.

Characterisation of protein families in spider digestive fluids and their role in extra-oral digestion.

Science.gov (United States)

Walter, André; Bechsgaard, Jesper; Scavenius, Carsten; Dyrlund, Thomas S; Sanggaard, Kristian W; Enghild, Jan J; Bilde, Trine

2017-08-10

Spiders are predaceous arthropods that are capable of subduing and consuming relatively large prey items compared to their own body size. For this purpose, spiders have evolved potent venoms to immobilise prey and digestive fluids that break down nutrients inside the prey's body by means of extra-oral digestion (EOD). Both secretions contain an array of active proteins, and an overlap of some components has been anecdotally reported, but not quantified. We systematically investigated the extent of such protein overlap. As venom injection and EOD succeed each other, we further infer functional explanations, and, by comparing two spider species belonging to different clades, assess its adaptive significance for spider EOD in general. We describe the protein composition of the digestive fluids of the mygalomorph Acanthoscurria geniculata and the araneomorph Stegodyphus mimosarum, in comparison with previously published data on a third spider species. We found a number of similar hydrolases being highly abundant in all three species. Among them, members of the family of astacin-like metalloproteases were particularly abundant. While the importance of these proteases in spider venom and digestive fluid was previously noted, we now highlight their widespread use across different spider taxa. Finally, we found species specific differences in the protein overlap between venom and digestive fluid, with the difference being significantly greater in S. mimosarum compared to A. geniculata. The injection of venom precedes the injection with digestive fluid, and the overlap of proteins between venom and digestive fluid suggests an early involvement in EOD. Species specific differences in the overlap may reflect differences in ecology between our two study species. The protein composition of the digestive fluid of all the three species we compared is highly similar, suggesting that the cocktail of enzymes is highly conserved and adapted to spider EOD.

Engineering Digestion: Multiscale Processes of Food Digestion.

Science.gov (United States)

Bornhorst, Gail M; Gouseti, Ourania; Wickham, Martin S J; Bakalis, Serafim

2016-03-01

Food digestion is a complex, multiscale process that has recently become of interest to the food industry due to the developing links between food and health or disease. Food digestion can be studied by using either in vitro or in vivo models, each having certain advantages or disadvantages. The recent interest in food digestion has resulted in a large number of studies in this area, yet few have provided an in-depth, quantitative description of digestion processes. To provide a framework to develop these quantitative comparisons, a summary is given here between digestion processes and parallel unit operations in the food and chemical industry. Characterization parameters and phenomena are suggested for each step of digestion. In addition to the quantitative characterization of digestion processes, the multiscale aspect of digestion must also be considered. In both food systems and the gastrointestinal tract, multiple length scales are involved in food breakdown, mixing, absorption. These different length scales influence digestion processes independently as well as through interrelated mechanisms. To facilitate optimized development of functional food products, a multiscale, engineering approach may be taken to describe food digestion processes. A framework for this approach is described in this review, as well as examples that demonstrate the importance of process characterization as well as the multiple, interrelated length scales in the digestion process. © 2016 Institute of Food Technologists®

[Anaerobic digestion of lignocellulosic biomass with animal digestion mechanisms].

Science.gov (United States)

Wu, Hao; Zhang, Pan-Yue; Guo, Jian-Bin; Wu, Yong-Jie

2013-02-01

Lignocellulosic material is the most abundant renewable resource in the earth. Herbivores and wood-eating insects are highly effective in the digestion of plant cellulose, while anaerobic digestion process simulating animal alimentary tract still remains inefficient. The digestion mechanisms of herbivores and wood-eating insects and the development of anaerobic digestion processes of lignocellulose were reviewed for better understanding of animal digestion mechanisms and their application in design and operation of the anaerobic digestion reactor. Highly effective digestion of lignocellulosic materials in animal digestive system results from the synergistic effect of various digestive enzymes and a series of physical and biochemical reactions. Microbial fermentation system is strongly supported by powerful pretreatment, such as rumination of ruminants, cellulase catalysis and alkali treatment in digestive tract of wood-eating insects. Oxygen concentration gradient along the digestive tract may stimulate the hydrolytic activity of some microorganisms. In addition, the excellent arrangement of solid retention time, digesta flow and end product discharge enhance the animal digestion of wood cellulose. Although anaerobic digestion processes inoculated with rumen microorganisms based rumen digestion mechanisms were developed to treat lignocellulose, the fermentation was more greatly limited by the environmental conditions in the anaerobic digestion reactors than that in rumen or hindgut. Therefore, the anaerobic digestion processes simulating animal digestion mechanisms can effectively enhance the degradation of wood cellulose and other organic solid wastes.

Life-cycle energy production and emissions mitigation by comprehensive biogas-digestate utilization.

Science.gov (United States)

Chen, Shaoqing; Chen, Bin; Song, Dan

2012-06-01

In the context of global energy shortages and climate change, developing biogas plants with links to agricultural system has become an important strategy for cleaner rural energy and renewable agriculture. In this study, a life-cycle energy and environmental assessment was performed for a biogas-digestate utilization system in China. The results suggest that biogas utilization (heating, illumination, and fuel) and comprehensive digestate reuse are of equal importance in the total energy production of the system, and they also play an important role in systemic greenhouse gas mitigation. Improvement can be achieved in both energy production and emissions mitigation when the ratio of the current three biogas utilization pathways is adjusted. Regarding digestate reuse, a tradeoff between energy and environmental performance can be obtained by focusing on the substitution for top-dressing, base fertilizers, and the application to seed soaking. Copyright © 2012 Elsevier Ltd. All rights reserved.

Digestive cell lysosomes as main targets for Ag accumulation and toxicity in marine mussels, Mytilus galloprovincialis, exposed to maltose-stabilised Ag nanoparticles of different sizes.

Science.gov (United States)

Jimeno-Romero, A; Bilbao, E; Izagirre, U; Cajaraville, M P; Marigómez, I; Soto, M

2017-03-01

Bioavailability and toxicity of maltose-stabilised AgNPs of different sizes (20, 40 and 100 nm) in mussels were compared with bulk and aqueous forms of the metal through a two-tier experimental approach. In the first tier, mussels were exposed for 3 d to a range of concentrations (0.75, 75, 750 μg Ag/l) in the form of Ag20-Mal, Ag40-Mal, Ag100-Mal, bulk Ag and aqueous Ag (as AgNO 3 ), as well as to the concentrations of maltose used in the formulation of NPs. Mortality, bioaccumulation, tissue and cell distribution and lysosomal responses were investigated. In the second tier, mussels were exposed for 21 d to Ag20-Mal, Ag100-Mal, bulk Ag and aqueous Ag at the lowest effective concentration selected after Tier 1 (0.75 μg Ag/l), biomarkers and toxicopathic effects were investigated. Aqueous Ag was lethal within 3 d at 75 μg Ag/l; Ag NPs or bulk Ag did not produce significant mortality at 750 μg Ag/l. Ag accumulation was limited and metallothionein gene transcription was not regulated although metal accumulation occurred in digestive, brown and stomach epithelial cells and in gut lumen after exposure to AgNPs and aqueous Ag starting at low concentrations after 1 d. Electrondense particles (lysosomes and residual bodies after exposure to AgNPs contained Ag and S (X-ray). Intralysosomal metal accumulation and lysosomal membrane destabilisation were enhanced after exposure to all the forms of Ag and more marked after exposure to Ag20-Mal than to larger NPs. 21 d exposure to AgNPs provoked digestive cell loss and loss of digestive gland integrity, resulting in atrophy-necrosis in digestive alveoli and oedema/hyperplasia in gills (Ag NP), vacuolisation in digestive cells (aqueous Ag) and haemocyte infiltration of connective tissue (all treatments). Intralysosomal metal accumulation, lysosomal responses and toxicopathic effects are enhanced at decreasing sizes and appear to be caused by Ag +  ions released from NPs, although the metal was not substantially

Optimized sizing model for renewable energy systems in rural areas; Modelo de dimensionamento otimizado para sistemas energeticos renovaveis em ambiente rurais

Energy Technology Data Exchange (ETDEWEB)

Nogueira, Carlos E.C. [UNIOESTE, Cascavel, PR (Brazil). Centro de Ciencias Exatas e Tecnologicas]. E-mail: cecn@correios.net.br; Zuern, Hans H. [Santa Catarina Univ., Florianopolis, SC (Brazil). Dept. de Engenharia Eletrica

2005-05-15

The purpose of this research was to develop a methodology for sizing integrated renewable energy systems, useful for rural areas, using simulation and optimization tools developed in MATLAB 6.0. The sizing model produces a system with minimum cost and high reliability level, based on the concept of loss of power supply probability (LPSP) for consecutive hours. An optimization model is presented and three different sizing scenarios are calculated and compared, showing flexibility in the elaboration of different project conceptions. The obtained results show a complete sizing of the energy conversion devices and a long-term cost evaluation. (author)

One Size Fits All? The Validity of a Composite Poverty Index Across Urban and Rural Households in South Africa.

Science.gov (United States)

Steinert, Janina Isabel; Cluver, Lucie Dale; Melendez-Torres, G J; Vollmer, Sebastian

2018-01-01

Composite indices have been prominently used in poverty research. However, validity of these indices remains subject to debate. This paper examines the validity of a common type of composite poverty indices using data from a cross-sectional survey of 2477 households in urban and rural KwaZulu-Natal, South Africa. Multiple-group comparisons in structural equation modelling were employed for testing differences in the measurement model across urban and rural groups. The analysis revealed substantial variations between urban and rural respondents both in the conceptualisation of poverty as well as in the weights and importance assigned to individual poverty indicators. The validity of a 'one size fits all' measurement model can therefore not be confirmed. In consequence, it becomes virtually impossible to determine a household's poverty level relative to the full sample. Findings from our analysis have important practical implications in nuancing how we can sensitively use composite poverty indices to identify poor people.

State-of-the-art of the development and appliance of anaerobic digestion in Brazil; Estagio de desenvolvimento e aplicacao da digestao anaerobica no Brasil

Energy Technology Data Exchange (ETDEWEB)

Hirata, Yukie Saito; Craveiro, Americo Martins [Instituto de Pesquisas Tecnologicas (IPT), Sao Paulo, SP (Brazil)

1988-12-31

This paper presents the up-to-date situation of both research and application of anaerobic digestion in Brazil. Concerning application, rural digesters have accounted around 7520 units and this number is expected to increase very slowly. For anaerobic treatment of industrial and domestic effluents, inversely, a rapid growth is expected for the near future. (author) 9 refs., 3 tabs.

The cost of digestion in the fish-eating myotis (Myotis vivesi).

Science.gov (United States)

Welch, Kenneth C; Otálora-Ardila, Aída; Herrera M, L Gerardo; Flores-Martínez, José Juan

2015-04-15

Flying vertebrates, such as bats, face special challenges with regards to the throughput and digestion of food. On the one hand, as potentially energy-limited organisms, bats must ingest and assimilate energy efficiently in order to satisfy high resting and active metabolic demands. On the other hand, the assimilation of nutrients must be accomplished using a digestive tract that is, compared with that of similarly sized non-flying vertebrates, significantly shorter. Despite these competing demands, and the relative breadth of dietary diversity among bats, little work has been done describing the cost of digestion, termed 'specific dynamic action' (SDA). Here, we provide the first systematic assessment of the SDA response in a bat, the fish-eating myotis (Myotis vivesi). Given the shorter digestive tract and the relatively higher resting and active metabolic rates of bats in general, and based on anecdotal published evidence, we hypothesized that the SDA response in fish-eating myotis would be dependent on meal size and both significantly more brief and intense than in small, non-flying mammals. In agreement with our hypothesis, we found that the peak metabolic rate during digestion, relative to rest, was significantly higher in these bats compared with any other mammals or vertebrates, except for some infrequently eating reptiles and amphibians. Additionally, we found that the magnitude and duration of the SDA response were related to meal size. However, we found that the duration of the SDA response, while generally similar to reported gut transit times in other small bats, was not substantially shorter than in similarly sized non-flying mammals. © 2015. Published by The Company of Biologists Ltd.

Nanoscale Molecules Under Thermodynamic Control:" Digestive Ripening" or " Nanomachining"

Energy Technology Data Exchange (ETDEWEB)

Klabunde, Kenneth J. [Kansas State Univ., Manhattan, KS (United States)

2015-06-04

Overall Research Goals and Specific Objectives: Nanoscale materials are becoming ubiquitous in science and engineering, and are found widely in nature. However, their formation processes and uniquely high chemical reactivities are not understood well, indeed are often mysterious. Over recent years, a number of research teams have described nanoparticle synthesis, and aging, thermal treatment, or etching times have been mentioned. We have used the terms “digestive ripening” and “nanomachining” and have suggested that thermodynamics plays an important part in the size adjustment to monodisperse arrays being formed. Since there is scant theoretical understanding of digestive ripening, the overall goal in our research is to learn what experimental parameters (ligand used, temperature, solvent, time) are most important, how to control nanoparticle size and shape after initial crude nanoparticles have been synthesized, and gain better understanding of the chemical mechanism details. Specific objectives for the past twentynine months since the grant began have been to (1) Secure and train personnel;as of 2011, a postdoc Deepa Jose, female from the Indian Institute of Science in Bangalore, India; Yijun Sun, a second year graduate student, female from China; and Jessica Changstrom, female from the USA, GK12 fellow (program for enhancing teaching ability) are actively carrying out research. (2) Find out what happens to sulfur bound hydrogen of thiol when it interacts with gold nanoparticles. Our findings are discussed in detail later. (3) Determine the effect of particle size, shape, and temperature on dodecyl thiol assited digestive ripening of gold nanoparticles. See our discussions later. (4) To understand in detail the ligand interaction in molecular clusters and nanoparticles (5) Determine the effect of chain length of amines on Au nanoparticle size under digestive ripening conditions (carbon chain length varied from 4-18). (6) Determine the catalytic activity

Model calibration and validation for OFMSW and sewage sludge co-digestion reactors

International Nuclear Information System (INIS)

Esposito, G.; Frunzo, L.; Panico, A.; Pirozzi, F.

2011-01-01

Highlights: → Disintegration is the limiting step of the anaerobic co-digestion process. → Disintegration kinetic constant does not depend on the waste particle size. → Disintegration kinetic constant depends only on the waste nature and composition. → The model calibration can be performed on organic waste of any particle size. - Abstract: A mathematical model has recently been proposed by the authors to simulate the biochemical processes that prevail in a co-digestion reactor fed with sewage sludge and the organic fraction of municipal solid waste. This model is based on the Anaerobic Digestion Model no. 1 of the International Water Association, which has been extended to include the co-digestion processes, using surface-based kinetics to model the organic waste disintegration and conversion to carbohydrates, proteins and lipids. When organic waste solids are present in the reactor influent, the disintegration process is the rate-limiting step of the overall co-digestion process. The main advantage of the proposed modeling approach is that the kinetic constant of such a process does not depend on the waste particle size distribution (PSD) and rather depends only on the nature and composition of the waste particles. The model calibration aimed to assess the kinetic constant of the disintegration process can therefore be conducted using organic waste samples of any PSD, and the resulting value will be suitable for all the organic wastes of the same nature as the investigated samples, independently of their PSD. This assumption was proven in this study by biomethane potential experiments that were conducted on organic waste samples with different particle sizes. The results of these experiments were used to calibrate and validate the mathematical model, resulting in a good agreement between the simulated and observed data for any investigated particle size of the solid waste. This study confirms the strength of the proposed model and calibration procedure

The morphometry of quadrifid digestive glands in traps of three Utricularia species: Does gland size correlate with trap size?

Czech Academy of Sciences Publication Activity Database

Adamec, Lubomír

2016-01-01

Roč. 56, č. 1 (2016), s. 27-38 ISSN 0079-2047 Institutional support: RVO:67985939 Keywords : aquatic Utricularia * traps * digestive-absorptive glands Subject RIV: EF - Botanics Impact factor: 0.500, year: 2016

Levels and Speciation of Platinum in Size-Fractionated Atmospheric Aerosol in Urban and Rural Sites across Europe

Science.gov (United States)

Shafer, Martin; Antkiewicz, Dagmara; Overdier, Joel; Schauer, James

2016-04-01

In this study we characterized the levels and speciation of platinum in a unique set of size-resolved atmospheric aerosol (PM) samples obtained from urban environments across Europe. From April-July 2012 we collected PM from roadside canyon, roadside motorway, and background urban sites in each of six European cities (Amsterdam, Frankfurt, London, Milan, Stockholm, and Thessaloniki). A Hi-Vol sampler was used to collect PM in three size classes (>PM7, PM7-PM3, PM3) and characterized for total platinum, soluble platinum (in a suite of physiologically relevant fluids - lung fluid (ALF), Gambles saline, 0.07M HCl, and MQ) and speciated forms (colloidal and anionic) within the soluble fractions. In addition we measured 50 other elements by SF-ICPMS, soluble ions by IC, and soluble organic carbon in the PM. Order-of-magnitude differences in air concentrations of total platinum were observed between urban sites, ranging from 4 to over 45 pg/m3; with a median level of 6 pg/m3. When platinum concentrations are normalized to PM mass the cross Europe and site-to-site variability was substantially reduced - a 3-fold variation from 200 to 600 ng/g was observed. Roadside canyon sites in London, Stockholm and Thessaloniki exhibited the highest concentrations; however levels at urban background sites were remarkably similar across the cities. Relatively consistent and low concentrations (1 to 2 pg/m3) of total platinum were observed at rural background sites across Europe. The contribution of coarse particles (>7 micron and 7-3 micron) to air concentrations of total platinum was very significant (>35% at nearly all sites). Soluble platinum fractions ranged from 2 to 6% (MQ to HCl) in rural background sites to 5 to 20% (MQ to HCl) in roadway canyon sites in London and Thessaloniki; with the extractable platinum fractions a strong function of pH. With the exception of urban canyon sites in London and Thessaloniki, soluble platinum concentrations in the fine aerosol (PM3) were all

Steam explosion pretreatment of softwood: the effect of the explosive decompression on enzymatic digestibility.

Science.gov (United States)

Pielhop, Thomas; Amgarten, Janick; von Rohr, Philipp Rudolf; Studer, Michael H

2016-01-01

Steam explosion pretreatment has been examined in many studies for enhancing the enzymatic digestibility of lignocellulosic biomass and is currently the most common pretreatment method in commercial biorefineries. The information available about the effect of the explosive decompression on the biochemical conversion is, however, very limited, and no studies prove that the latter is actually enhanced by the explosion. Hence, it is of great value to discern between the effect of the explosion on the one hand and the steaming on the other hand, to identify their particular influences on enzymatic digestibility. The effect of the explosive decompression in the steam explosion pretreatment of spruce wood chips on their enzymatic cellulose digestibility was studied systematically. The explosion had a high influence on digestibility, improving it by up to 90 % compared to a steam pretreatment without explosion. Two factors were identified to be essentially responsible for the effect of the explosion on enzymatic digestibility: pretreatment severity and pressure difference of the explosion. A higher pretreatment severity can soften up and weaken the lignocellulose structure more, so that the explosion can better break up the biomass and decrease its particle size, which enhances its digestibility. In particular, increasing the pressure difference of the explosion leads to more defibration, a smaller particle size and a better digestibility. Though differences were found in the micro- and nanostructure of exploded and non-exploded biomass, the only influence of the explosion on digestibility was found to be the macroscopic particle size reduction. Steam explosion treatments with a high severity and a high pressure difference of the explosion lead to a comparatively high cellulose digestibility of the-typically very recalcitrant-softwood biomass. This is the first study to show that explosion can enhance the enzymatic digestibility of lignocellulosic biomass. If the

Validation of an in vitro digestive system for studying macronutrient decomposition in humans.

Science.gov (United States)

Kopf-Bolanz, Katrin A; Schwander, Flurina; Gijs, Martin; Vergères, Guy; Portmann, Reto; Egger, Lotti

2012-02-01

The digestive process transforms nutrients and bioactive compounds contained in food to physiologically active compounds. In vitro digestion systems have proven to be powerful tools for understanding and monitoring the complex transformation processes that take place during digestion. Moreover, the investigation of the physiological effects of certain nutrients demands an in vitro digestive process that is close to human physiology. In this study, human digestion was simulated with a 3-step in vitro process that was validated in depth by choosing pasteurized milk as an example of a complex food matrix. The evolution and decomposition of the macronutrients was followed over the entire digestive process to the level of intestinal enterocyte action, using protein and peptide analysis by SDS-PAGE, reversed-phase HPLC, size exclusion HPLC, and liquid chromatography-MS. The mean peptide size after in vitro digestion of pasteurized milk was 5-6 amino acids (AA). Interestingly, mostly essential AA (93.6%) were released during in vitro milk digestion, a significantly different relative distribution compared to the total essential AA concentration of bovine milk (44.5%). All TG were degraded to FFA and monoacylglycerols. Herein, we present a human in vitro digestion model validated for its ability to degrade the macronutrients of dairy products comparable to physiological ranges. It is suited to be used in combination with a human intestinal cell culture system, allowing ex vivo bioavailability measurements and assessment of the bioactive properties of food components.

Improved Design of Anaerobic Digesters for Household Biogas Production in Indonesia: One Cow, One Digester, and One Hour of Cooking per Day

OpenAIRE

Usack, Joseph G.; Wiratni, Wiratni; Angenent, Largus T.

2014-01-01

A government-sponsored initiative in Indonesia to design and implement low-cost anaerobic digestion systems resulted in 21 full-scale systems with the aim to satisfy the cooking fuel demands of rural households owning at least one cow. The full-scale design consisted of a 0.3 m diameter PVC pipe, which was operated as a conventional plug-flow system. The system generated enough methane to power a cooking stove for ∼ 1 h. However, eventual clogging from solids accumulation inside the bioreacto...

The influence of neighbors' family size preference on progression to high parity births in rural Nepal.

Science.gov (United States)

Jennings, Elyse A; Barber, Jennifer S

2013-03-01

Large families can have a negative impact on the health and well-being of women, children, and their communities. Seventy-three percent of the individuals in our rural Nepalese sample report that two children is their ideal number, yet about half of the married women continue childbearing after their second child. Using longitudinal data from the Chitwan Valley Family Study, we explore the influence of women's and neighbors' family size preferences on women's progression to high parity births, comparing this influence across two cohorts. We find that neighbors' family size preferences influence women's fertility, that older cohorts of women are more influenced by their neighbors' preferences than are younger cohorts of women, and that the influence of neighbors' preferences is independent of women's own preferences. © 2013 The Population Council, Inc.

Low-heat, mild alkaline pretreatment of switchgrass for anaerobic digestion.

Science.gov (United States)

Jin, Guang; Bierma, Tom; Walker, Paul M

2014-01-01

This study examines the effectiveness of alkaline pretreatment under mild heat conditions (100°C or 212°F) on the anaerobic co-digestion of switchgrass. The effects of alkaline concentration, types of alkaline, heating time and rinsing were evaluated. In addition to batch studies, continuous-feed studies were performed in triplicate to identify potential digester operational problems caused by switchgrass co-digestion while accounting for uncertainty due to digester variability. Few studies have examined anaerobic digestion of switchgrass or the effects of mild heating to enhance alkaline pretreatment prior to biomass digestion. Results indicate that pretreatment can significantly enhance digestion of coarse-ground (≤ 0.78 cm particle size) switchgrass. Energy conversion efficiency as high as 63% was observed, and was comparable or superior to fine-grinding as a pretreatment method. The optimal NaOH concentration was found to be 5.5% (wt/wt alkaline/biomass) with a 91.7% moisture level. No evidence of operational problems such as solids build-up, poor mixing, or floating materials were observed. These results suggest the use of waste heat from a generator could reduce the concentration of alkaline required to adequately pretreat lignocellulosic feedstock prior to anaerobic digestion.

Digestive Diseases

Science.gov (United States)

... cells and provide energy. This process is called digestion. Your digestive system is a series of hollow organs joined ... are also involved. They produce juices to help digestion. There are many types of digestive disorders. The ...

Normative influence and desired family size among young people in rural Egypt.

Science.gov (United States)

Harbour, Catherine

2011-06-01

Research has identified the lack of acceptance of a two-child-family norm as the biggest obstacle to achieving replacement-level fertility in Egypt. This analysis examines norms about desired family size for 1,366 males and 1,367 females aged 15-24 in 2004 in rural Minya governorate. Two-level random-effects multivariate logistic regression models, stratified by sex and grouped by neighborhood, are used to assess normative influence at the household and neighborhood levels, controlling for individual- and household-level covariates. In the final model, young males in neighborhoods where more people desire a small family are 33 percent more likely to desire a small family than are young males in other neighborhoods. Young females in households with one or more adults preferring a small family are 78 percent more likely to desire a small family, and young females in households with one or more young people who prefer a small family are 37 percent more likely to desire a small family themselves, compared with those living with adults or with young people, respectively, who do not prefer a small family. Programs aiming to reduce fertility should be aware of gender differences in the sources of normative influence on desired family size.

Forage fiber effects on particle size reduction, ruminal stratification, and selective retention in heifers fed highly digestible grass/clover silages

DEFF Research Database (Denmark)

Schulze, Anne-Katrine Skovsted; Weisbjerg, Martin Riis; Storm, Adam Christian

2014-01-01

The objective of this study was to investigate the effect of NDF content in highly digestible grass/clover silage on particle size reduction, ruminal stratification, and selective retention in dairy heifers. The reduction in particle size from feed to feces was evaluated and related to feed intake...... measured. Intake of NDF increased linearly from 2.3 to 2.8 kg/d with greater NDF content of forages (P = 0.01), but silages were exposed to similar eating time (P = 0.55) and rumination time per kg NDF (P = 0.35). No linear effect of NDF content was found on proportion of LP in ingested feed boluses (P = 0.......31), medial rumen digesta (P = 0.95), ventral rumen digesta (P = 0.84), and feces (P = 0.09). Greater proportions of DM (P ruminal digesta compared with ventral rumen, and differences in DM proportion increased with greater NDF content (P = 0...

Anaerobic digestion of organic by-products from meat-processing industry. The effect of pre-treatments and co-digestion

Energy Technology Data Exchange (ETDEWEB)

Luste, S.

2011-07-01

Anaerobic digestion is a multi-beneficial biological treatment during which micro-organisms degrade organic material producing biogas (i.e. methane) and stabilised end-product (i.e. digestate). Methane is a versatile renewable energy source and digestate can be used as an organic fertiliser and/or soil improver. Because of the increasing consumption and tightening environment and health legislation, production of organic wastes suitable for anaerobic digestion increases. Animal by-products (ABP) from the meat-processing industry are often rendered (contaminated material), used as feedstock (in fur breeding), or composted. However, ABPs studied could not be utilised in fodder or in animal food production and have currently been rendered or directed to composting, despite being mostly considered unsuitable for composting. Many ABPs are energy-rich, wet and pasty materials and suitable for the anaerobic digestion process. Moreover, suitable pre-treatment to hydrolyse solid materials and/or co-digestion of two or several materials may improve the anaerobic digestion with ultimate goal to increase the methane production, stabilisation and reusability of digestate. The case chosen for more detailed research was that of a middle-sized Finnish meat-processing industry. The aim of the thesis was to evaluate the feasibility of different ABPs presently available for treatment as raw material for anaerobic digestion. Another objective was to enhance the anaerobic digestion process via specific pre-treatments and co-digestion cases with the ultimate aim to increase the methane production and the quality of the digestate. The general goal was to observe the overall process from the perspective of real-circumstances in Finland to rise to needs in practice and to produce exploitable information for adopting sustainable development locally and case-specifically into practice via versatile anaerobic digestion technology. The ABPs studied were highly bio-degradable and especially

Rural Tourism - Alternative to the Development of Rural Areas

Directory of Open Access Journals (Sweden)

Maria Cristina PAIU

2017-06-01

Full Text Available Rural tourism through its content and its features is a distinct component in the economy of a region, and the sustainable, efficient use of local tourism resources can be an extremely important activity by: adding added value, boosting productivity, employment and increasing the living standard of the population. Rural tourism is considered a lever to mitigate local imbalances and besides attracting touristic areas in the circuit, it also has consequences on territorial development: housing construction, road development, development of public services and the development of small and medium-sized enterprises. Consequently, rural tourism has an impact on a country's economic and social development strategy, but also on a branch level.

Decentralized Biogas Technology of Anaerobic Digestion and Farm Ecosystem: Opportunities and Challenges

Energy Technology Data Exchange (ETDEWEB)

Wang, Junye, E-mail: junyew@athabascau.ca [Faculty of Science and Technology, Athabasca University, Athabasca, AB (Canada)

2014-03-26

Long-term economic and environmental concerns have resulted in a great amount of research on renewable sources of biomass and bioenergy to replace fossil fuels in the past decades. Decentralized biogas technology is one of the most potential technologies of biomass and bioenergy by using agricultural waste materials (e.g., animal manure, crop straw, and by-products from food industries) as feedstocks. By-products from biogas production, called digestate, are nutrient rich, which could potentially be reused as green fertilizers in agriculture, thereby providing a sustainable substitute for synthetic fertilizers for farm ecosystem. Thus, the biogas production of anaerobic digestion is win–win option for livestock and crop producers to address issues of waste management and energy supply, and to avoid contamination of surface and ground waters and emissions of odors and greenhouse gases. In this paper, we review biogas production technology and then evaluate environmental effects of digestate used as fertilizer. Finally, we discuss issues of deployment of decentralized biogas technology for farm ecosystem. Economic and technological barriers still exist for large scale deployment of biogas technology in rural region. Two national scale deployments in China and Nepal showed that the operational status of biogas digesters is not optimal and up to 50% of plants are non-functional after a short operation period regardless of the social and economic factors. Main barriers are a wide variation of feedstocks and environmental conditions (e.g., temperature) over space and time. It becomes clear that the experimental conditions of the pilot plants need to be adjusted and calibrated to the local feedstocks and climate. Also, more research needs to be done in cold fermentation technology. Thus, collaboration of all relevant designers, farmers, stakeholders, and regulators is proposed as the way forward, particularly as their complexity has been identified as the major hurdle

Decentralized Biogas Technology of Anaerobic Digestion and Farm Ecosystem: Opportunities and Challenges

International Nuclear Information System (INIS)

Wang, Junye

2014-01-01

Long-term economic and environmental concerns have resulted in a great amount of research on renewable sources of biomass and bioenergy to replace fossil fuels in the past decades. Decentralized biogas technology is one of the most potential technologies of biomass and bioenergy by using agricultural waste materials (e.g., animal manure, crop straw, and by-products from food industries) as feedstocks. By-products from biogas production, called digestate, are nutrient rich, which could potentially be reused as green fertilizers in agriculture, thereby providing a sustainable substitute for synthetic fertilizers for farm ecosystem. Thus, the biogas production of anaerobic digestion is win–win option for livestock and crop producers to address issues of waste management and energy supply, and to avoid contamination of surface and ground waters and emissions of odors and greenhouse gases. In this paper, we review biogas production technology and then evaluate environmental effects of digestate used as fertilizer. Finally, we discuss issues of deployment of decentralized biogas technology for farm ecosystem. Economic and technological barriers still exist for large scale deployment of biogas technology in rural region. Two national scale deployments in China and Nepal showed that the operational status of biogas digesters is not optimal and up to 50% of plants are non-functional after a short operation period regardless of the social and economic factors. Main barriers are a wide variation of feedstocks and environmental conditions (e.g., temperature) over space and time. It becomes clear that the experimental conditions of the pilot plants need to be adjusted and calibrated to the local feedstocks and climate. Also, more research needs to be done in cold fermentation technology. Thus, collaboration of all relevant designers, farmers, stakeholders, and regulators is proposed as the way forward, particularly as their complexity has been identified as the major hurdle

Libyan intuitive for rural electrification

International Nuclear Information System (INIS)

Ibrahim, I. M. Saleh; Kreama, N. M.; Khalat, M. A.

2006-01-01

One of the obstacles in rural electrification is choosing the type of the electric source which best fits rural areas technically, socially, and economically. Renewable sources can be used to electrify rural areas. Rural electrification in Libya by photovoltaic systems in a national program which is devoted to electrify isolated villages, as part of this program the installation of 300 systems was started at the beginning of the year 2003 with a total power of 400 K Wp, the sizes of stand alone systems are 1.8 K Wp, 1.2 K Wp, 0.75 K Wp, and 0.15 K Wp, beside a hybrid system of diesel and PV. The systems was designed to supply different family needs a total of 5000 inhabitants will benefit from this project. In this paper we will introduce the rural photovoltaic electrification in Libya program, company the performance of three different PV sizes through the first two years of working. The systems performing well and with performance ratio much more than the deigned, very little power failure was reported, and there are social and technical issues to be addressed before, and after the installation of the PV system.(Author)

Thirty or sixty percent milk replacer reduction for calves: effects on alfalfa hay intake and digestibility, digestive kinetics and ruminal fermentation.

Science.gov (United States)

Broesder, J T; Judkins, M B; Krysl, L J; Gunter, S A; Barton, R K

1990-09-01

Twelve artificially reared, male Holstein calves, ruminally cannulated at 53 d of age, were used in a split-plot design to study the effects of no milk replacer reduction (CON), or reduction by 30% (30R) or 60% (60R) of this value on alfalfa hay intake and digestibility, ruminal fermentation and digestive kinetics. Milk replacer reduction began at 53 d of age and continued until 135 d of age, after which no milk replacer was fed. All calves had ad libitum access to long-stemmed alfalfa hay from birth. Five collection periods were conducted at average calf ages of 72, 87, 108, 129 and 151 d. Reducing the amount of milk replacer fed resulted in a linear increase (P less than .05) in forage OM intake; however, total OM intake (forage + milk) was not different (P greater than .10) among milk reduction groups. Size of particles in feces exhibited quadratic effects in response to milk replacer reduction (P less than .05) but only in the small (less than 150 microns) size groupings. Ruminal pH and ammonia and individual VFA concentrations (except isobutyrate) were not altered by milk reduction (P greater than .10) but increased (P less than .01) with calf age. Milk replacer reduction had a quadratic effect (P less than .05) on fluid outflow rate from the rumen, increasing as milk replacer was reduced. Other fluid and particulate kinetic data, as well as NDF digestion rate and DM digestion showed no effects (P greater than .10) from milk replacer reduction but changed with calf age. Milk replacer reduction increased forage intake but had minimal effects on digestive variables evaluated, suggesting that intake of milk replacer by calves can be reduced by up to 60% without disturbing forage fermentation and passage.

In vivo digestion of bovine milk fat globules: effect of processing and interfacial structural changes. I. Gastric digestion.

Science.gov (United States)

Gallier, Sophie; Cui, Jack; Olson, Trent D; Rutherfurd, Shane M; Ye, Aiqian; Moughan, Paul J; Singh, Harjinder

2013-12-01

The aim was to study the in vivo gastric digestion of fat globules in bovine cream from raw, pasteurised or pasteurised and homogenised milk. Fasted rats were gavaged once and chyme samples were collected after 30, 120 and 180 min post-gavage. Proteins from raw (RC) and pasteurised (PC) creams appeared to be digested faster and to a greater extent. Free fatty acids (FAs) increased throughout the 3h postprandial period. Short and medium chain FAs were released more rapidly than long chain FAs which were hydrolysed to a greater degree from PC. The size of the fat globules of all creams increased in the stomach. Protein aggregates were observed in pasteurised and homogenised cream chyme. Protrusions, probably caused by the accumulation of insoluble lipolytic products, appeared at the surface of the globules in RC and PC chyme. Overall, PC proteins and lipids appeared to be digested to a greater extent. Copyright © 2013 Elsevier Ltd. All rights reserved.

Chromosome sizes and phylogenetic relationships between serotypes of Actinobacillus pleuropneumoniae

OpenAIRE

Chevallier, Bruno; Dugourd, Dominique; Tarasiuk, Kazimirez; Harel, Josée; Gottschalk, Marcelo; Kobisch, Marylène; Frey, Joachim

2017-01-01

The genome size of Actinobacillus pleuropneumoniae was determined by pulsed field gel electrophoresis of AscI and ApaI digested chromosomal DNA. The genome size of the type strain 4074T (serotype 1) was determined to be 2404±40 kb. The chromosome sizes for the reference strains of the other serotypes range between 2.3 and 2.4 Mb. The restriction pattern profiles of AscI, ApaI and NheI digested chromosomes showed a high degree of polymorphism among the different serotype reference strains and ...

Comparative Digestive Physiology

Science.gov (United States)

Karasov, William H.; Douglas, Angela E.

2015-01-01

In vertebrates and invertebrates, morphological and functional features of gastrointestinal (GI) tracts generally reflect food chemistry, such as content of carbohydrates, proteins, fats, and material(s) refractory to rapid digestion (e.g., cellulose). The expression of digestive enzymes and nutrient transporters approximately matches the dietary load of their respective substrates, with relatively modest excess capacity. Mechanisms explaining differences in hydrolase activity between populations and species include gene copy number variations and single-nucleotide polymorphisms. Transcriptional and posttranscriptional adjustments mediate phenotypic changes in the expression of hydrolases and transporters in response to dietary signals. Many species respond to higher food intake by flexibly increasing digestive compartment size. Fermentative processes by symbiotic microorganisms are important for cellulose degradation but are relatively slow, so animals that rely on those processes typically possess special enlarged compartment(s) to maintain a microbiota and other GI structures that slow digesta flow. The taxon richness of the gut microbiota, usually identified by 16S rRNA gene sequencing, is typically an order of magnitude greater in vertebrates than invertebrates, and the interspecific variation in microbial composition is strongly influenced by diet. Many of the nutrient transporters are orthologous across different animal phyla, though functional details may vary (e.g., glucose and amino acid transport with K+ rather than Na+ as a counter ion). Paracellular absorption is important in many birds. Natural toxins are ubiquitous in foods and may influence key features such as digesta transit, enzymatic breakdown, microbial fermentation, and absorption PMID:23720328

Pretreatments to enhance the digestibility of lignocellulosic biomass

NARCIS (Netherlands)

Hendriks, A.T.W.M.; Zeeman, G.

2009-01-01

Lignocellulosic biomass represents a rather unused source for biogas and ethanol production. Many factors, like lignin content, crystallinity of cellulose, and particle size, limit the digestibility of the hemicellulose and cellulose present in the lignocellulosic biomass. Pretreatments have as a

Principals as Assessment Leaders in Rural Schools

Science.gov (United States)

Renihan, Patrick; Noonan, Brian

2012-01-01

This article reports a study of rural school principals' assessment leadership roles and the impact of rural context on their work. The study involved three focus groups of principals serving small rural schools of varied size and grade configuration in three systems. Principals viewed assessment as a matter of teacher accountability and as a…

Energy conservation and self-sufficiency in rural property; Geracao e auto-suficiencia de energias em imovel rural familiar

Energy Technology Data Exchange (ETDEWEB)

Schuch, Sergio Luis [Instituto Paranaense de Assistencia Tecnica e Extensao Rural (EMATER), Toledo, PR (Brazil)], e-mail: slschuch@hotmail.com; Lawder, Jose Henrique [Evolucao Engenharia Eletrica, Toledo, PR (Brazil)], e-mail: jose_lawder@uol.com.br; Feiden, Armin; Nogueira, Carlos Eduardo Camargo; Siqueira, Jair Antonio Cruz [Universidade Estadual do Oeste do Parana (UNIOESTE), Cascavel, PR (Brazil)], e-mails: armin_feiden@yahoo.com.br, cecn1@yahoo.com.br, jairsiqueira@unioeste.br

2011-07-01

This paper aims to highlight an innovative system designed to generate bioenergy in Toledo - PR, applied in a rural residential property. This system is composed by a simple digester model, because it eliminates masonry and hood storage. Cattle slurry and water from barn's floor cleaning are conducted to an anaerobic biodigester chamber. Biogas production is stored in a polypropylene canvas balloon. After compression, the biogas is used to replace liquefied petroleum gas in central water heating and cooking foods. The wood used in sugar cane molasses has been replaced with higher efficiency by biogas. Also was installed Otto engine providing thermal and electrical power generation at the same time. The electrical power output is biphasic and about 70 Amperes. This system deployed in rural property provides energy self-sufficiency and contribute to the reduction of operational costs of the property. (author)

Energy conservation and self-sufficiency in rural property; Geracao e auto-suficiencia de energias em imovel rural familiar

Energy Technology Data Exchange (ETDEWEB)

Schuch, Sergio Luis [Instituto Paranaense de Assistencia Tecnica e Extensao Rural (EMATER), Toledo, PR (Brazil)], e-mail: slschuch@hotmail.com; Lawder, Jose Henrique [Evolucao Engenharia Eletrica, Toledo, PR (Brazil)], e-mail: jose_lawder@uol.com.br; Feiden, Armin; Nogueira, Carlos Eduardo Camargo; Siqueira, Jair Antonio Cruz [Universidade Estadual do Oeste do Parana (UNIOESTE), Cascavel, PR (Brazil)], e-mails: armin_feiden@yahoo.com.br, cecn1@yahoo.com.br, jairsiqueira@unioeste.br

2011-07-01

This paper aims to highlight an innovative system designed to generate bioenergy in Toledo - PR, applied in a rural residential property. This system is composed by a simple digester model, because it eliminates masonry and hood storage. Cattle slurry and water from barn's floor cleaning are conducted to an anaerobic biodigester chamber. Biogas production is stored in a polypropylene canvas balloon. After compression, the biogas is used to replace liquefied petroleum gas in central water heating and cooking foods. The wood used in sugar cane molasses has been replaced with higher efficiency by biogas. Also was installed Otto engine providing thermal and electrical power generation at the same time. The electrical power output is biphasic and about 70 Amperes. This system deployed in rural property provides energy self-sufficiency and contribute to the reduction of operational costs of the property. (author)

Family Size and Rural Poverty -in the Kwahu South District in Ghana ...

African Journals Online (AJOL)

Rural Poverty is one of the greatest social problems confronting the world today. The problem is more pronounced in the developing countries. Ghana is no exception to this global problem of rural poverty. Ghana as a nation has adopted a lot of measures to address poverty. From the early 1980's to 2002, the country has ...

Poor prognosis of hexokinase 2 overexpression in solid tumors of digestive system: a meta-analysis.

Science.gov (United States)

Wu, Jiayuan; Hu, Liren; Wu, Fenping; Zou, Lei; He, Taiping

2017-05-09

Several previous studies have reported the prognostic value of hexokinase 2 (HK2) in digestive system tumors. However, these studies were limited by the small sample sizes and the results were inconsistent among them. Therefore, we conducted a meta-analysis based on 15 studies with 1932 patients to assess the relationship between HK2 overexpression and overall survival (OS) of digestive system malignancies. The relationship of HK2 and clinicopathological features was also evaluated. Hazard ratio (HR) or odds ratio (OR) with its 95% confidence intervals (CI) were calculated to estimate the effect size. Positive HK2 expression showed poor OS in all tumor types (HR = 1.75 [1.41-2.18], P digestive system cancers.

Financial Performance of Rural Medicare ACOs.

Science.gov (United States)

Nattinger, Matthew C; Mueller, Keith; Ullrich, Fred; Zhu, Xi

2018-12-01

The Centers for Medicare & Medicaid Services (CMS) has facilitated the development of Medicare accountable care organizations (ACOs), mostly through the Medicare Shared Savings Program (MSSP). To inform the operation of the Center for Medicare & Medicaid Innovation's (CMMI) ACO programs, we assess the financial performance of rural ACOs based on different levels of rural presence. We used the 2014 performance data for Medicare ACOs to examine the financial performance of rural ACOs with different levels of rural presence: exclusively rural, mostly rural, and mixed rural/metropolitan. Of the ACOs reporting performance data, we identified 97 ACOs with a measurable rural presence. We found that successful rural ACO financial performance is associated with the ACO's organizational type (eg, physician-based) and that 8 of the 11 rural ACOs participating in the Advanced Payment Program (APP) garnered savings for Medicare. Unlike previous work, we did not find an association between ACO size or experience and rural ACO financial performance. Our findings suggest that rural ACO financial success is likely associated with factors unique to rural environments. Given the emphasis CMS has placed on rural ACO development, further research to identify these factors is warranted. © 2016 National Rural Health Association.

Developmental plasticity of growth and digestive efficiency in dependence of early-life food availability

Science.gov (United States)

Kotrschal, Alexander; Szidat, Sönke; Taborsky, Barbara

2014-01-01

Nutrition is a potent mediator of developmental plasticity. If food is scarce, developing organisms may invest into growth to outgrow size-dependent mortality (short-term benefit) and/or into an efficient digestion system (long-term benefit). We investigated this potential trade-off, by determining the influence of food availability on juvenile body and organ growth, and on adult digestive efficiency in the cichlid fish Simochromis pleurospilus. We reared two groups of fish at constant high or low food rations, and we switched four other groups between these two rations at an early and late juvenile period. We measured juvenile growth and organ sizes at different developmental stages and determined adult digestive efficiency. Fish kept at constant, high rations grew considerably faster than low-food fish. Nevertheless, S. pleurospilus partly buffered the negative effects of low food availability by developing heavier digestive organs, and they were therefore more efficient in digesting their food as adults. Results of fish exposed to a ration switch during either the early or late juvenile period suggest (i) that the ability to show compensatory growth after early exposure to low food availability persists during the juvenile period, (ii) that digestive efficiency is influenced by varying juvenile food availability during the late juvenile phase and (iii) that the efficiency of the adult digestive system is correlated with the growth rate during a narrow time window of juvenile period. PMID:25866430

Parasitic infections of digestive tract of dogs in territory of Braničevo District

OpenAIRE

Đurić, Boban; Ilić, Tamara; Trailović, Dragiša; Kulišić, Zoran; Dimitrijević, Sanda

2011-01-01

This paper presents the results of two-year investigations of parasitic infections of the digestive tract of dogs originating from the territories of eight municipalities of Braničevo District. Investigations were performed on 345 dogs of different breeds and age categories, originating from rural and urban environments. The investigations encompassed dogs bred in decent hygiene conditions, as well as dogs living in unhygienic conditions. Some of the dogs c...

Household anaerobic digester for bioenergy production in developing countries: opportunities and challenges.

Science.gov (United States)

Surendra, K C; Takara, Devin; Jasinski, Jonas; Khanal, Samir Kumar

2013-01-01

Access to clean and affordable energy is vital for advancing development objectives, particularly in rural areas of developing countries. There are some three billion people in these regions, however, who lack consistent access to energy and rely on traditional solid fuels such as firewood, cattle manure, and crop residues for meeting cooking and heating needs. Excessive use of such highly polluting resources creates serious environmental, social and public health issues. In this context, household digesters (which convert readily available feedstocks such as cattle manure, human excreta, and crop residues into biogas) have the potential to play a significant role in supplying methane as a clean, renewable energy resource for remote geographies. In addition to bioenergy production, the slurry generated from anaerobic digestion is rich in nutrients and can improve the physical, chemical, and biological attributes of soil when applied to agricultural land. This type of approach has the potential to significantly reduce greenhouse gas emissions while simultaneously improving the quality of life. Despite a long history of research and innovation for the development and optimization of household digesters, little is known and has been reported for the application of these systems in decentralized communities. The primary purpose of this paper seeks to review the dearth of literature pertaining to small-scale anaerobic digesters in remote geographies and in regions where much of the world's population reside.

Digestibility of gluten proteins is reduced by baking and enhanced by starch digestion.

Science.gov (United States)

Smith, Frances; Pan, Xiaoyan; Bellido, Vincent; Toole, Geraldine A; Gates, Fred K; Wickham, Martin S J; Shewry, Peter R; Bakalis, Serafim; Padfield, Philip; Mills, E N Clare

2015-10-01

Resistance of proteins to gastrointestinal digestion may play a role in determining immune-mediated adverse reactions to foods. However, digestion studies have largely been restricted to purified proteins and the impact of food processing and food matrices on protein digestibility is poorly understood. Digestibility of a total gliadin fraction (TGF), flour (cv Hereward), and bread was assessed using in vitro batch digestion with simulated oral, gastric, and duodenal phases. Protein digestion was monitored by SDS-PAGE and immunoblotting using monoclonal antibodies specific for celiac-toxic sequences (QQSF, QPFP) and starch digestion by measuring undigested starch. Whereas the TGF was rapidly digested during the gastric phase the gluten proteins in bread were virtually undigested and digested rapidly during the duodenal phase only if amylase was included. Duodenal starch digestion was also slower in the absence of duodenal proteases. The baking process reduces the digestibility of wheat gluten proteins, including those containing sequences active in celiac disease. Starch digestion affects the extent of protein digestion, probably because of gluten-starch complex formation during baking. Digestion studies using purified protein fractions alone are therefore not predictive of digestion in complex food matrices. © 2015 The Authors. Molecular Nutrition & Food Research published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Physicochemical properties and starch digestibility of Chinese noodles in relation to optimal cooking time.

Science.gov (United States)

Ye, Xiaoting; Sui, Zhongquan

2016-03-01

Changes in the physicochemical properties and starch digestibility of white salted noodles (WSN) at different cooking stage were investigated. The noodles were dried in fresh air and then cooked for 2-12 min by boiling in distilled water to determine the properties of cooking quality, textural properties and optical characteristic. For starch digestibility, dry noodles were milled and sieved into various particle size classes ranging from 0.5 mm to 5.0 mm, and hydrolyzed by porcine pancreatic α-amylase. The optimal cooking time of WSN determined by squeezing between glasses was 6 min. The results showed that the kinetics of solvation of starch and protein molecules were responsible for changes of the physicochemical properties of WSN during cooking. The susceptibility of starch to α-amylase was influenced by the cooking time, particle size and enzyme treatment. The greater value of rapidly digestible starch (RDS) and lower value of slowly digestible starch (SDS) and resistant starch (RS) were reached at the optimal cooking stage ranging between 63.14-71.97%, 2.47-10.74% and 23.94-26.88%, respectively, indicating the susceptibility on hydrolysis by enzyme was important in defining the cooked stage. The study suggested that cooking quality and digestibility were not correlated but the texture greatly controls the digestibility of the noodles. Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of Acylglycerol Composition and Fatty Acyl Chain Length on Lipid Digestion in pH-Stat Digestion Model and Simulated In Vitro Digestion Model.

Science.gov (United States)

Qi, Jin F; Jia, Cai H; Shin, Jung A; Woo, Jeong M; Wang, Xiang Y; Park, Jong T; Hong, Soon T; Lee, K-T

2016-02-01

In this study, a pH-stat digestion model and a simulated in vitro digestion model were employed to evaluate the digestion degree of lipids depending on different acylglycerols and acyl chain length (that is, diacylglycerol [DAG] compared with soybean oil representing long-chain triacylglycerol compared with medium-chain triacylglycerol [MCT]). In the pH-stat digestion model, differences were observed among the digestion degrees of 3 oils using digestion rate (k), digestion half-time (t1/2 ), and digestion extent (Φmax). The results showed the digestion rate order was MCT > soybean oil > DAG. Accordingly, the order of digestion half-times was MCT digestion model, digestion rates (k') and digestion half-times (t'1/2 ) were also obtained and the results showed a digestion rate order of MCT (k' = 0.068 min(-1) ) > soybean oil (k' = 0.037 min(-1) ) > DAG (k' = 0.024 min(-1) ). Consequently, the order of digestion half-times was MCT (t'1/2 = 10.20 min) digested faster than soybean oil, and that soybean oil was digested faster than DAG. © 2015 Institute of Food Technologists®

Carcinoids tumors of the digestive tract

International Nuclear Information System (INIS)

Carvalho, S.M.R. de; Prais, M.; Matushita, J.P.K.; Matushita, J.S.

1989-01-01

Eighteen cases of carcinoid tumors in the digestive tract have been analyzed. They have been selected at Hospital dos Servidores do Estado do Rio de Janeiro, taking into account patients, age and sex, lesions' location and size, clinical manifestations, presence of metastases as well as a classical carcinoid syndrome establisment. Carcinoid tumors come from the digestive tract 'argenta fim'' cells, the ones which produce endocrines. Such endocrines are responsible for a great number of clinical manifestations. The classical syndrome is directly related to the presence of hepatic metastases. The authors propose to correlate what has been found with descriptions in medical literature emphasizing the radiographic aspects which have been observed. A frequent ''apendicular'' location and the difficulty of giving a precise diagnosis before surgery is also emphasized. (author) [pt

Anaerobic co-digestion of canola straw and buffalo dung: optimization of methane production in batch experiments

International Nuclear Information System (INIS)

Sahito, A.R.; Brohi, K.M.

2014-01-01

In several regions of the Pakistan, crop cultivation is leading to the production crop residues and its disposal problems. It has been suggested that the co-digestion of the crop residues with the buffalo dung might be a disposal way for the wasted portion of the crops residue. The objective of present study was to optimize the anaerobic co-digestion of canola straw and the buffalo dung through batch experiments in order to obtain maximum methane production. The optimization was carried out in three stages. In first stage, the best canola straw to buffalo dung ratio was evaluated. In second stage, the best concentration of sodium hydrogen carbonate was assessedas the alkaline pretreatment chemical, whereas in the third stage most suitable particle size of the canola strawwas evaluated. The assessment criteria for the optimization of a co-digestion were cumulative methane production and ABD (Anaerobic Biodegradability). The results yield that anaerobic co-digestibility of the canola straw and the buffalo dung is obviously influenced by all the three factors of optimization. The maximum methane production was obtained as 911 NmL from the canola straw to buffalo dung ratio of 40:60, the alkaline doze of 0.6 gNaHCO/sub 3/ gVS and canola straw particle size of 2mm. However, because of the higher shredding cost to produce 2mm sized canola straw, particle size 4mm could be the best canola straw particle size. (author)

Anaerobic Co-Digestion of Canola Straw and Buffalo Dung: Optimization of Methane Production in Batch Experiments

Directory of Open Access Journals (Sweden)

Abdul Razaque Sahito

2014-01-01

Full Text Available In several regions of the Pakistan, crop cultivation is leading to the production crop residues and its disposal problems. It has been suggested that the co-digestion of the crop residues with the buffalo dung might be a disposal way for the wasted portion of the crops' residue. The objective of present study was to optimize the anaerobic co-digestion of canola straw and the buffalo dung through batch experiments in order to obtain maximum methane production. The optimization was carried out in three stages. In first stage, the best canola straw to buffalo dung ratio was evaluated. In second stage, the best concentration of sodium hydrogen carbonate was assessedas the alkaline pretreatment chemical, whereas in the third stage most suitable particle size of the canola strawwas evaluated. The assessment criteria for the optimization of a co-digestion were cumulative methane production and ABD (Anaerobic Biodegradability. The results yield that anaerobic co-digestibility of the canola straw and the buffalo dung is obviously influenced by all the three factors of optimization. The maximum methane production was obtained as 911 NmL from the canola straw to buffalo dung ratio of 40:60, the alkaline doze of 0.6 gNaHCO3 / gVS and canola straw particle size of 2mm. However, because of the higher shredding cost to produce 2mm sized canola straw, particle size 4mm could be the best canola straw particle size.

CFD simulation of gas and non-Newtonian fluid two-phase flow in anaerobic digesters.

Science.gov (United States)

Wu, Binxin

2010-07-01

This paper presents an Eulerian multiphase flow model that characterizes gas mixing in anaerobic digesters. In the model development, liquid manure is assumed to be water or a non-Newtonian fluid that is dependent on total solids (TS) concentration. To establish the appropriate models for different TS levels, twelve turbulence models are evaluated by comparing the frictional pressure drops of gas and non-Newtonian fluid two-phase flow in a horizontal pipe obtained from computational fluid dynamics (CFD) with those from a correlation analysis. The commercial CFD software, Fluent12.0, is employed to simulate the multiphase flow in the digesters. The simulation results in a small-sized digester are validated against the experimental data from literature. Comparison of two gas mixing designs in a medium-sized digester demonstrates that mixing intensity is insensitive to the TS in confined gas mixing, whereas there are significant decreases with increases of TS in unconfined gas mixing. Moreover, comparison of three mixing methods indicates that gas mixing is more efficient than mixing by pumped circulation while it is less efficient than mechanical mixing.

Transforming anaerobic digestion with the Model T of digesters

Energy Technology Data Exchange (ETDEWEB)

Martin, J.F.; Ciotola, R.; Castano, J.; Eger, C.; Schlea, D. [Ohio State Univ., Columbus, OH (United States). Ecological Engineering Program

2010-07-01

Most livestock farmers in the United States do not take advantage of anaerobic digester technology because of the high cost and large scale. These limitations therefore reduce the production of renewable energy from farmlands. In order to expand anaerobic digestion methods and improve environmental quality, affordable and smaller-scale digesters should be developed to enable most livestock farmers to convert manure to methane. Doing so would improve their economic efficiency and environmental sustainability. This paper provided an analogy to the development of the Model T to better explain the need and potential for this technology. A modified fixed-dome digester was installed on the Ohio State University dairy in Columbus, Ohio. The digester was unheated, buried, had a volume of 1 m{sup 3} and received diluted dairy manure as feedstock. Biogas was produced at digester temperatures as low 10 degrees C during colder ambient temperatures. Water quality also improved. Results from the first year of operation will be analyzed to improve performance and enable future development of this technology.

Anaerobic Digestion: Process

DEFF Research Database (Denmark)

Angelidaki, Irini; Batstone, Damien J.

2011-01-01

Organic waste may degrade anaerobically in nature as well as in engineered systems. The latter is called anaerobic digestion or biogasification. Anaerobic digestion produces two main outputs: An energy-rich gas called biogas and an effluent. The effluent, which may be a solid as well as liquid...... with very little dry matter may also be called a digest. The digest should not be termed compost unless it specifically has been composted in an aerated step. This chapter describes the basic processes of anaerobic digestion. Chapter 9.5 describes the anaerobic treatment technologies, and Chapter 9...

Anaerobic digestion apparatus and process. Procede et installation de digestion anaerobie

Energy Technology Data Exchange (ETDEWEB)

De Baere, L.

1989-05-09

This invention concerns a process for the anaerobic digestion of apparently solid organic matter. The matter is mixed and kneaded with an inoculant to form an apparently solid mass having a water content which varies from around 55 wt % to around 75 wt %. This mass is then introduced into a digestor, where it is digested for a period of around less than 50 days. The biogas produced during the anaerobic digestion stage is recovered, said biogas being a byproduct of the digestion process. The digested mass is extracted, and at least a third, by weight, of that mass is recycled to act as the inoculant. The non-recycled digested mass is removed.

Effects of continuous addition of nitrate to a thermophilic anaerobic digestion system

International Nuclear Information System (INIS)

Rivard, C.J.

1983-01-01

The biodegradation of complex organic matter is regulated partially by the ability to dump electrons which build up in the form of reduced nicotinamide adenine dinucleotide (NAD). The effects of the continuous addition of the oxidant, nitrate, were investigated on a single-stage, thermophilic, anaerobic digester. The digester acclimated rapidly to nitrate addition. The continuous addition of nitrate resulted in a constant inhibition of total gas (30%) and methane production (36%). Reduction in total gas and methane production was accompanied by increases in sludge pH and acetate, propionate, and ammonium ion pools. Effluent particle size distribution revealed a shift to smaller particle sizes in the nitrate-pumped sludge. The continuous addition of nitrate resulted in lower numbers of methanogens and sulfate reducers in the sludge, with increases in nitrate-reducing and cellulose-degrading microorganisms. These findings indicate that added nitrate underwent dissimilatory reduction to ammonium ion, as determined from gas analysis, ammonium pools, and 15 N-nitrate-label experiments. Continuous nitrate addition to a single-phase digestion system was determined to inhibit methane production from biomass and wastes. Thus for the single-stage digestion system in which maximum methane production is desired, the addition of nitrate is not recommended. However, in a multistage digestion system, the continuous addition of nitrate in the primary stage to increase the rate and extent of degradation of organic matter to volatile fatty acids, which then would serve as feed to a second stage, may be advantageous

Access to Productive Resources: The Catalyst to Rural Women's ...

African Journals Online (AJOL)

However, rural women in post-apartheid South Africa are experiencing hardships in laying hold of such resources. The pertinent questions the article seeks to interrogate are: who should determine the resource needs of rural women? Are the one size fit all programmes ideal for alleviating rural women's poverty. This article ...

Downstream reduction of rural channel size with contrasting urban effects in small coastal streams of southeastern Australia

Science.gov (United States)

Nanson, G. C.; Young, R. W.

1981-07-01

Although most streams show a downstream increase in channel size corresponding to a downstream increase in flood discharges, those flowing off the Illawarra escarpment of New South Wales show a marked reduction of channel size, accompanied by a down-stream increase in flood frequency in their lower reaches. Within the confined and steeply sloping valleys of the escarpment foothills, bed and bank sediments are relatively coarse and uncohesive, and channels increase in size, corresponding to increasing discharge downstream. However, once these streams emerge into more open rural valleys at lower slopes and are accompanied by extensive floodplains formed of fine cohesive sediment, there is a dramatic reduction in channel size. This decrease in channel size apparently results from a sudden decline in channel slope and associated stream power, the cohesive nature of downstream alluvium, its retention on the channel banks by a dense cover of pasture grasses, and the availability of an extensive floodplain to carry displaced floodwater. Under these conditions floodwaters very frequently spill out over the floodplain and the downstream channel-flow becomes a relatively unimportant component of the total peak discharge. This emphasizes the importance of these floodplains as a part of the total channel system. In situations where urban development has increased peak runoff and reduced the available area of effective floodplain, stream channels formed in this fine alluvium rapidly entrench and increase in cross-sectional area by 2-3 times. Minor man-induced channel alteration and maintenance appears to trigger this enlargement.

Body size and hosts of Triatoma infestans populations affect the size of bloodmeal contents and female fecundity in rural northwestern Argentina.

Science.gov (United States)

Gürtler, Ricardo E; Fernández, María Del Pilar; Cecere, María Carla; Cohen, Joel E

2017-12-01

Human sleeping quarters (domiciles) and chicken coops are key source habitats of Triatoma infestans-the principal vector of the infection that causes Chagas disease-in rural communities in northern Argentina. Here we investigated the links among individual bug bloodmeal contents (BMC, mg), female fecundity, body length (L, mm), host blood sources and habitats. We tested whether L, habitat and host blood conferred relative fitness advantages using generalized linear mixed-effects models and a multimodel inference approach with model averaging. The data analyzed include 769 late-stage triatomines collected in 120 sites from six habitats in 87 houses in Figueroa, Santiago del Estero, during austral spring. L correlated positively with other body-size surrogates and was modified by habitat type, bug stage and recent feeding. Bugs from chicken coops were significantly larger than pig-corral and kitchen bugs. The best-fitting model of log BMC included habitat, a recent feeding, bug stage, log Lc (mean-centered log L) and all two-way interactions including log Lc. Human- and chicken-fed bugs had significantly larger BMC than bugs fed on other hosts whereas goat-fed bugs ranked last, in consistency with average blood-feeding rates. Fecundity was maximal in chicken-fed bugs from chicken coops, submaximal in human- and pig-fed bugs, and minimal in goat-fed bugs. This study is the first to reveal the allometric effects of body-size surrogates on BMC and female fecundity in a large set of triatomine populations occupying multiple habitats, and discloses the links between body size, microsite temperatures and various fitness components that affect the risks of transmission of Trypanosoma cruzi.

Body size and hosts of Triatoma infestans populations affect the size of bloodmeal contents and female fecundity in rural northwestern Argentina.

Directory of Open Access Journals (Sweden)

Ricardo E Gürtler

2017-12-01

Full Text Available Human sleeping quarters (domiciles and chicken coops are key source habitats of Triatoma infestans-the principal vector of the infection that causes Chagas disease-in rural communities in northern Argentina. Here we investigated the links among individual bug bloodmeal contents (BMC, mg, female fecundity, body length (L, mm, host blood sources and habitats. We tested whether L, habitat and host blood conferred relative fitness advantages using generalized linear mixed-effects models and a multimodel inference approach with model averaging. The data analyzed include 769 late-stage triatomines collected in 120 sites from six habitats in 87 houses in Figueroa, Santiago del Estero, during austral spring. L correlated positively with other body-size surrogates and was modified by habitat type, bug stage and recent feeding. Bugs from chicken coops were significantly larger than pig-corral and kitchen bugs. The best-fitting model of log BMC included habitat, a recent feeding, bug stage, log Lc (mean-centered log L and all two-way interactions including log Lc. Human- and chicken-fed bugs had significantly larger BMC than bugs fed on other hosts whereas goat-fed bugs ranked last, in consistency with average blood-feeding rates. Fecundity was maximal in chicken-fed bugs from chicken coops, submaximal in human- and pig-fed bugs, and minimal in goat-fed bugs. This study is the first to reveal the allometric effects of body-size surrogates on BMC and female fecundity in a large set of triatomine populations occupying multiple habitats, and discloses the links between body size, microsite temperatures and various fitness components that affect the risks of transmission of Trypanosoma cruzi.

Anaerobic co-digestion of dairy manure and potato waste

Science.gov (United States)

Yadanaparthi, Sai Krishna Reddy

Dairy and potato are two important agricultural commodities in Idaho. Both the dairy and potato processing industries produce a huge amount of waste which could cause environmental pollution. To minimize the impact of potential pollution associated with dairy manure (DM) and potato waste (PW), anaerobic co-digestion has been considered as one of the best treatment process. The purpose of this research is to evaluate the anaerobic co-digestion of dairy manure and potato waste in terms of process stability, biogas generation, construction and operating costs, and potential revenue. For this purpose, I conducted 1) a literature review, 2) a lab study on anaerobic co-digestion of dairy manure and potato waste at three different temperature ranges (ambient (20-25°C), mesophilic (35-37°C) and thermophilic (55-57°C) with five mixing ratios (DM:PW-100:0, 90:10, 80:20, 60:40, 40:60), and 3) a financial analysis for anaerobic digesters based on assumed different capital costs and the results from the lab co-digestion study. The literature review indicates that several types of organic waste were co-digested with DM. Dairy manure is a suitable base matter for the co-digestion process in terms of digestion process stability and methane (CH4) production (Chapter 2). The lab tests showed that co-digestion of DM with PW was better than digestion of DM alone in terms of biogas and CH4 productions (Chapter 3). The financial analysis reveals DM and PW can be used as substrate for full size anaerobic digesters to generate positive cash flow within a ten year time period. Based on this research, the following conclusions and recommendations were made: ▸ The ratio of DM:PW-80:20 is recommended at thermophilic temperatures and the ratio of DM:PW-90:10 was recommended at mesophilic temperatures for optimum biogas and CH4 productions. ▸ In cases of anaerobic digesters operated with electricity generation equipment (generators), low cost plug flow digesters (capital cost of 600/cow

[The rural population problem in China and its solution].

Science.gov (United States)

Zhao, S

1980-03-01

The author discusses the question of whether the size of China's rural population, representing approximately 85 percent of the total population, is too large. Suggestions for reducing the size of the rural population are considered, including the development of brigade- and commune-level enterprises, the development of industries in newly emerging urban areas, the development of satellite towns, and the encouragement of internal migration.

Measuring the attractiveness of rural communities in accounting for differences of rural primary care workforce supply.

Science.gov (United States)

McGrail, Matthew R; Wingrove, Peter M; Petterson, Stephen M; Humphreys, John S; Russell, Deborah J; Bazemore, Andrew W

2017-01-01

Many rural communities continue to experience an undersupply of primary care doctor services. While key professional factors relating to difficulties of recruitment and retention of rural primary care doctors are widely identified, less attention has been given to the role of community and place aspects on supply. Place-related attributes contribute to a community's overall amenity or attractiveness, which arguably influence both rural recruitment and retention relocation decisions of doctors. This bi-national study of Australia and the USA, two developed nations with similar geographic and rural access profiles, investigates the extent to which variations in community amenity indicators are associated with spatial variations in the supply of rural primary care doctors. Measures from two dimensions of community amenity: geographic location, specifically isolation/proximity; and economics and sociodemographics were included in this study, along with a proxy measure (jurisdiction) of a third dimension, environmental amenity. Data were chiefly collated from the American Community Survey and the Australian Census of Population and Housing, with additional calculated proximity measures. Rural primary care supply was measured using provider-to-population ratios in 1949 US rural counties and in 370 Australian rural local government areas. Additionally, the more sophisticated two-step floating catchment area method was used to measure Australian rural primary care supply in 1116 rural towns, with population sizes ranging from 500 to 50 000. Associations between supply and community amenity indicators were examined using Pearson's correlation coefficients and ordinary least squares multiple linear regression models. It was found that increased population size, having a hospital in the county, increased house prices and affluence, and a more educated and older population were all significantly associated with increased workforce supply across rural areas of both countries

Digestion proteomics: tracking lactoferrin truncation and peptide release during simulated gastric digestion.

Science.gov (United States)

Grosvenor, Anita J; Haigh, Brendan J; Dyer, Jolon M

2014-11-01

The extent to which nutritional and functional benefit is derived from proteins in food is related to its breakdown and digestion in the body after consumption. Further, detailed information about food protein truncation during digestion is critical to understanding and optimising the availability of bioactives, in controlling and limiting allergen release, and in minimising or monitoring the effects of processing and food preparation. However, tracking the complex array of products formed during the digestion of proteins is not easily accomplished using classical proteomics. We here present and develop a novel proteomic approach using isobaric labelling to mapping and tracking protein truncation and peptide release during simulated gastric digestion, using bovine lactoferrin as a model food protein. The relative abundance of related peptides was tracked throughout a digestion time course, and the effect of pasteurisation on peptide release assessed. The new approach to food digestion proteomics developed here therefore appears to be highly suitable not only for tracking the truncation and relative abundance of released peptides during gastric digestion, but also for determining the effects of protein modification on digestibility and potential bioavailability.

Neutral fat hydrolysis and long-chain fatty acid oxidation during anaerobic digestion of slaughterhouse wastewater.

Science.gov (United States)

Masse, L; Massé, D I; Kennedy, K J; Chou, S P

2002-07-05

Neutral fat hydrolysis and long-chain fatty acid (LCFA) oxidation rates were determined during the digestion of slaughterhouse wastewater in anaerobic sequencing batch reactors operated at 25 degrees C. The experimental substrate consisted of filtered slaughterhouse wastewater supplemented with pork fat particles at various average initial sizes (D(in)) ranging from 60 to 450 microm. At the D(in) tested, there was no significant particle size effect on the first-order hydrolysis rate. The neutral fat hydrolysis rate averaged 0.63 +/- 0.07 d(-1). LCFA oxidation rate was modelled using a Monod-type equation. The maximum substrate utilization rate (kmax) and the half-saturation concentration (Ks) averaged 164 +/- 37 mg LCFA/L/d and 35 +/- 31 mg LCFA/L, respectively. Pork fat particle degradation was mainly controlled by LCFA oxidation rate and, to a lesser extent, by neutral fat hydrolysis rate. Hydrolysis pretreatment of fat-containing wastewaters and sludges should not substantially accelerate their anaerobic treatment. At a D(in) of 450 microm, fat particles were found to inhibit methane production during the initial 20 h of digestion. Inhibition of methane production in the early phase of digestion was the only significant effect of fat particle size on anaerobic digestion of pork slaughterhouse wastewater. Soluble COD could not be used to determine the rate of lipid hydrolysis due to LCFA adsorption on the biomass.

Assessment of by-products of bioenergy systems (anaerobic digestion and gasification) as potential crop nutrient.

Science.gov (United States)

Kataki, Sampriti; Hazarika, Samarendra; Baruah, D C

2017-01-01

-products were found to be within the permitted range specified for organic fertilizer (vermicompost) in India. However, higher Al content of the digestates in whole, solid and ash phase (0.06-16.97gkg -1 fresh matter) can be a concern in acid soil which may cause Al toxicity. Understanding on agrochemical characteristics of bioenergy by-products with varying feedstock and application option is expected to promote their valorization opportunities considering user specific requirements. In the context of agriculturally dominant but energy deficient rural Indian scenario, integrated production of bioenergy and by-product based fertilizer could be very significant to meet the critical additional requirement of both energy and fertilizer. Copyright © 2016 Elsevier Ltd. All rights reserved.

Prediction of in vivo neutral detergent fiber digestibility and digestion rate of potentially digestible neutral detergent fiber: comparison of models.

Science.gov (United States)

Huhtanen, P; Seppälä, A; Ahvenjärvi, S; Rinne, M

2008-10-01

Eleven 1-pool, seven 2-pool, and three 3-pool models were compared in fitting gas production data and predicting in vivo NDF digestibility and effective first-order digestion rate of potentially digestible NDF (pdNDF). Isolated NDF from 15 grass silages harvested at different stages of maturity was incubated in triplicate in rumen fluid-buffer solution for 72 h to estimate the digestion kinetics from cumulative gas production profiles. In vivo digestibility was estimated by the total fecal collection method in sheep fed at a maintenance level of feeding. The concentration of pdNDF was estimated by a 12-d in situ incubation. The parameter values from gas production profiles and pdNDF were used in a 2-compartment rumen model to predict pdNDF digestibility using 50 h of rumen residence time distributed in a ratio of 0.4:0.6 between the non-escapable and escapable pools. The effective first-order digestion rate was computed both from observed in vivo and model-predicted pdNDF digestibility assuming the passage kinetic model described above. There were marked differences between the models in fitting the gas production data. The fit improved with increasing number of pools, suggesting that silage pdNDF is not a homogenous substrate. Generally, the models predicted in vivo NDF digestibility and digestion rate accurately. However, a good fit of gas production data was not necessarily translated into improved predictions of the in vivo data. The models overestimating the asymptotic gas volumes tended to underestimate the in vivo digestibility. Investigating the time-related residuals during the later phases of fermentation is important when the data are used to estimate the first-order digestion rate of pdNDF. Relatively simple models such as the France model or even a single exponential model with discrete lag period satisfied the minimum criteria for a good model. Further, the comparison of feedstuffs on the basis of parameter values is more unequivocal than in the case

Digested disorder

Science.gov (United States)

DeForte, Shelly; Reddy, Krishna D; Uversky, Vladimir N

2013-01-01

The current literature on intrinsically disordered proteins is overwhelming. To keep interested readers up to speed with this literature, we continue a “Digested Disorder” project and represent a series of reader’s digest type articles objectively representing the research papers and reviews on intrinsically disordered proteins. The only 2 criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the period of April, May, and June of 2013. The papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings. PMID:28516028

Does rural space benefit from location of anaerobic digestion plants? Perspective of communal administration

Czech Academy of Sciences Publication Activity Database

Martinát, Stanislav; Mintálová, T.; Dvořák, Petr; Navrátil, J.; Klusáček, Petr; Kunc, J.

2013-01-01

Roč. 7, č. 2 (2013), s. 41-49 ISSN 1337-6748 R&D Projects: GA MŠk EE2.3.20.0025 Institutional support: RVO:68145535 Keywords : renewable sources of energy * public acceptance * a naerobic digestion plants * the Czech Republic Subject RIV: DE - Earth Magnetism, Geodesy, Geography http://geografia.science.upjs.sk/images/geographia_cassoviensis/articles/GC-2013-7-2/Martinat_akol_tlac3.pdf

Anaerobic digestion and co-digestion of slaughterhouse wastes

Directory of Open Access Journals (Sweden)

Sonia Castellucci

2013-09-01

Full Text Available The use of renewable energy is becoming increasingly necessary in order to address the global warming problem and, as a consequence, has become an high priority for many countries. Biomass is a clean and renewable energy source with growing potential to replace conventional fossil fuels. Among biomass, residual and waste ones represent a great resource for energy generation since they permit both to eliminate a possible waste and to produce energy. In the present work, the case of slaughterhouse wastes (SHWs has been investigated. Anaerobic digestion is nowadays considered as one of the most important and sustainable conversion technology exploiting organic matter and biodegradable wastes. Biogas results from this bio-chemical process and mainly consists of methane and carbon dioxide, leading to produce thermal energy and/or electricity. In this paper, the European Regulations on animal by-products (ABPs are described, and some previous study on anaerobic digestion and co-digestion of ABPs - more precisely SHWs - are considered and compared in order to fix a starting point for future tests on their co-digestion in a micro-scale pilot digester. This is to define optimal feed ratio values which ensure an increasing content of methane in the outgoing biogas.

Long-term thermophilic mono-digestion of rendering wastes and co-digestion with potato pulp

International Nuclear Information System (INIS)

Bayr, S.; Ojanperä, M.; Kaparaju, P.; Rintala, J.

2014-01-01

Highlights: • Rendering wastes’ mono-digestion and co-digestion with potato pulp were studied. • CSTR process with OLR of 1.5 kg VS/m 3 d, HRT of 50 d was unstable in mono-digestion. • Free NH 3 inhibited mono-digestion of rendering wastes. • CSTR process with OLR of 1.5 kg VS/m 3 d, HRT of 50 d was stable in co-digestion. • Co-digestion increased methane yield somewhat compared to mono-digestion. - Abstract: In this study, mono-digestion of rendering wastes and co-digestion of rendering wastes with potato pulp were studied for the first time in continuous stirred tank reactor (CSTR) experiments at 55 °C. Rendering wastes have high protein and lipid contents and are considered good substrates for methane production. However, accumulation of digestion intermediate products viz., volatile fatty acids (VFAs), long chain fatty acids (LCFAs) and ammonia nitrogen (NH 4 -N and/or free NH 3 ) can cause process imbalance during the digestion. Mono-digestion of rendering wastes at an organic loading rate (OLR) of 1.5 kg volatile solids (VS)/m 3 d and hydraulic retention time (HRT) of 50 d was unstable and resulted in methane yields of 450 dm 3 /kg VS fed . On the other hand, co-digestion of rendering wastes with potato pulp (60% wet weight, WW) at the same OLR and HRT improved the process stability and increased methane yields (500–680 dm 3 /kg VS fed ). Thus, it can be concluded that co-digestion of rendering wastes with potato pulp could improve the process stability and methane yields from these difficult to treat industrial waste materials

PELATIHAN TEKNOLOGI FERMENTASI KOMBINASI FESES SAPI DAN BABI DALAM DIGESTER MOBILE SEBAGAI UPAYA PRODUKSI BIOENERGI ALTERNATIF

Directory of Open Access Journals (Sweden)

Suryatika Suryatika

2012-10-01

Full Text Available Has done community service in order to provide the knowledge and skills to members of a group of cattle in the village of Pengotan, Bangli about how processing cow manure and pig waste into biogas, as an environmentally friendly alternative energy. Method of activities with demoplot how to create installations, mobile digester, which is a fermentation tank where the cow and pig feces to produce biogas (bioenergy is ready to use. The group of farmers who participated in the training activities of household-scale biogas production is very enthusiastic follow until the end. Almost 100% of participants acknowledged that mobile digester offered as a place of production of biogas can be accepted and become the solution of cultural problems that have been developed in rural areas Pengotan.

Interactions between seed traits and digestive processes determine the germinability of bird-dispersed seeds.

Science.gov (United States)

Kleyheeg, Erik; Claessens, Mascha; Soons, Merel B

2018-01-01

Waterbirds disperse a wide range of plant seeds via their guts, promoting biotic connectivity between isolated habitat patches. However, the intensity of digestive forces encountered by seeds, and therefore their potential to survive digestive tract passage, varies within and between waterbird species. Here, we investigate under controlled conditions how the interaction between seed traits and digestive strategies affect the germinability of seeds following waterbird-mediated dispersal. We exposed seeds of 30 wetland plant species to the main digestive processes in the dabbling duck digestive system: mechanical, chemical and intestinal digestion. These were simulated by 1) a pressure test and scarification treatment, 2) incubation in simulated gastric juice, and 3) incubation in intestinal contents of culled mallards (Anas platyrhynchos). We evaluated their separate and combined effects on seed germination, and identified the role of seed size and seed coat traits in resisting the digestive forces. Seeds were generally resistant to separate digestive processes, but highly sensitive to a combination. Resistance to mechanical break-down was reduced by up to 80% by chemical pre-treatment, especially for seeds with permeable coats. Scarified seeds were 12-17% more vulnerable to chemical and intestinal digestive processes than undamaged seeds. Large seeds and seeds with thin, permeable coats were particularly sensitive to chemical and intestinal digestion. These results indicate that efficient digestion of seeds requires multiple digestive processes. The gizzard, responsible for mechanical digestion, plays a key role in seed survival. Omnivorous birds, which have relatively light gizzards compared to pure herbivores or granivores, are thus most likely to disperse seeds successfully. Regardless of digestive strategy, small seeds with tough seed coats are most resistant to digestion and may be adapted to endozoochorous dispersal by waterbirds.

Interactions between seed traits and digestive processes determine the germinability of bird-dispersed seeds

Science.gov (United States)

Soons, Merel B.

2018-01-01

Waterbirds disperse a wide range of plant seeds via their guts, promoting biotic connectivity between isolated habitat patches. However, the intensity of digestive forces encountered by seeds, and therefore their potential to survive digestive tract passage, varies within and between waterbird species. Here, we investigate under controlled conditions how the interaction between seed traits and digestive strategies affect the germinability of seeds following waterbird-mediated dispersal. We exposed seeds of 30 wetland plant species to the main digestive processes in the dabbling duck digestive system: mechanical, chemical and intestinal digestion. These were simulated by 1) a pressure test and scarification treatment, 2) incubation in simulated gastric juice, and 3) incubation in intestinal contents of culled mallards (Anas platyrhynchos). We evaluated their separate and combined effects on seed germination, and identified the role of seed size and seed coat traits in resisting the digestive forces. Seeds were generally resistant to separate digestive processes, but highly sensitive to a combination. Resistance to mechanical break-down was reduced by up to 80% by chemical pre-treatment, especially for seeds with permeable coats. Scarified seeds were 12–17% more vulnerable to chemical and intestinal digestive processes than undamaged seeds. Large seeds and seeds with thin, permeable coats were particularly sensitive to chemical and intestinal digestion. These results indicate that efficient digestion of seeds requires multiple digestive processes. The gizzard, responsible for mechanical digestion, plays a key role in seed survival. Omnivorous birds, which have relatively light gizzards compared to pure herbivores or granivores, are thus most likely to disperse seeds successfully. Regardless of digestive strategy, small seeds with tough seed coats are most resistant to digestion and may be adapted to endozoochorous dispersal by waterbirds. PMID:29614085

African and local wind-blown dist contributions at three rural sites in SE Spain: the aerosol size distribution

International Nuclear Information System (INIS)

Orza, J. A. G.; Cabello, M.; Lidon, V.; Martinez, J.

2009-01-01

The entrainment of particulate material into the atmosphere by wind action on surface soils both disturbed and natural, as well as directly due to human activities like agricultural practices, mineral industry operations, construction works and traffic, is a significant contribution to the aerosol load in Mediterranean semi-arid areas. A further crustal contribution in the region comes from the frequent arrival of African mineral dust plumes. We summarize some of the results obtained after 4-6 month campaigns at three rural sites in SE Spain where the aerosol number size distribution (31 size bins between 0.25 and 32 μm) was continuously measured. The influence of both local wind speed and the arrival of air masses loaded with African dust on the airborne particulate distribution is assessed. Similarities and differences between the three locations give information that allows a better understanding of the influence of both local wind speed and African dust outbreaks (ADO), while highlight what is mostly related to local features. (Author)

Anaerobic Digestion and its Applications

Science.gov (United States)

Anaerobic digestion is a natural biological process. The initials "AD" may refer to the process of anaerobic digestion, or the built systems of anaerobic digesters. While there are many kinds of digesters, the biology is basically the same for all. Anaerobic digesters are built...

Stochastic modelling of the economic viability of on-farm co-digestion of pig manure and food waste in Ireland

International Nuclear Information System (INIS)

Dennehy, C.; Lawlor, P.G.; Gardiner, G.E.; Jiang, Y.; Shalloo, L.; Zhan, X.

2017-01-01

Highlights: •Assessed economic viability of on-farm manure mono- and co-digestion. •Assessed three farm sizes: 521 sows; 2607 sows; and 5214 sows. •Mono-digestion of manure alone not economically viable. •Co-digestion viable on small farms as food waste likely to be sourced. •Viability on larger farms dependent on securing sufficient food waste. -- Abstract: The majority of studies analysing the economic potential of biogas systems utilise deterministic models to assess the viability of a system using fixed inputs. However, changes in market conditions can significantly affect the viability of biogas plants, and need to be accounted for. This study assessed the economic potential of undertaking on-farm anaerobic co-digestion of food waste (FW) and pig manure (PM) using both deterministic and stochastic modelling approaches. The financial viability of three co-digestion plants sized to treat PM generated from 521, 2607 and 5214 sow integrated units was assessed. Under current market conditions the largest co-digestion scenario modelled was found to be unviable. Stochastic modelling of four key input variables (FW availability, renewable electricity tariff, gate fees and digestate disposal costs) was undertaken to assess the sensitivity of project viability to changes in market conditions. Due to the high likelihood of accessing sufficient FW, the smallest co-digestion scenario was found to be the least sensitive to any future changes in market conditions. Due to its potential to treat greater amounts of FW than the smallest scenario, a co-digestion plant designed for a 2607 sow farm had the highest revenue generating potential under optimal market conditions; however, it was more sensitive to changes in FW availability than the smaller scenario. This study illustrates the need for farm-based biogas plant projects to secure long-term, stable supplies of co-substrates and to size plants’ capacity based on the availability of the co-substrates which drive

Digested disorder

Science.gov (United States)

Reddy, Krishna D; DeForte, Shelly; Uversky, Vladimir N

2014-01-01

The current literature on intrinsically disordered proteins grows fast. To keep interested readers up to speed with this literature, we continue a “Digested Disorder” project and represent a new issue of reader’s digest of the research papers and reviews on intrinsically disordered proteins. The only 2 criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the third quarter of 2013; i.e., during the period of June, July, and September of 2013. Similar to previous issues, the papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings. PMID:28232877

The oldest known digestive system consisting of both paired digestive glands and a crop from exceptionally preserved trilobites of the Guanshan Biota (Early Cambrian, China.

Directory of Open Access Journals (Sweden)

Melanie J Hopkins

Full Text Available The early Cambrian Guanshan biota of eastern Yunnan, China, contains exceptionally preserved animals and algae. Most diverse and abundant are the arthropods, of which there are at least 11 species of trilobites represented by numerous specimens. Many trilobite specimens show soft-body preservation via iron oxide pseudomorphs of pyrite replacement. Here we describe digestive structures from two species of trilobite, Palaeolenus lantenoisi and Redlichia mansuyi. Multiple specimens of both species contain the preserved remains of an expanded stomach region (a "crop" under the glabella, a structure which has not been observed in trilobites this old, despite numerous examples of trilobite gut traces from other Cambrian Lagerstätten. In addition, at least one specimen of Palaeolenus lantenoisi shows the preservation of an unusual combination of digestive structures: a crop and paired digestive glands along the alimentary tract. This combination of digestive structures has also never been observed in trilobites this old, and is rare in general, with prior evidence of it from one juvenile trilobite specimen from the late Cambrian Orsten fauna of Sweden and possibly one adult trilobite specimen from the Early Ordovician Fezouata Lagerstätte. The variation in the fidelity of preservation of digestive structures within and across different Lagerstätten may be due to variation in the type, quality, and point of digestion of food among specimens in addition to differences in mode of preservation. The presence and combination of these digestive features in the Guanshan trilobites contradicts current models of how the trilobite digestive system was structured and evolved over time. Most notably, the crop is not a derived structure as previously proposed, although it is possible that the relative size of the crop increased over the evolutionary history of the clade.

The oldest known digestive system consisting of both paired digestive glands and a crop from exceptionally preserved trilobites of the Guanshan Biota (Early Cambrian, China).

Science.gov (United States)

Hopkins, Melanie J; Chen, Feiyang; Hu, Shixue; Zhang, Zhifei

2017-01-01

The early Cambrian Guanshan biota of eastern Yunnan, China, contains exceptionally preserved animals and algae. Most diverse and abundant are the arthropods, of which there are at least 11 species of trilobites represented by numerous specimens. Many trilobite specimens show soft-body preservation via iron oxide pseudomorphs of pyrite replacement. Here we describe digestive structures from two species of trilobite, Palaeolenus lantenoisi and Redlichia mansuyi. Multiple specimens of both species contain the preserved remains of an expanded stomach region (a "crop") under the glabella, a structure which has not been observed in trilobites this old, despite numerous examples of trilobite gut traces from other Cambrian Lagerstätten. In addition, at least one specimen of Palaeolenus lantenoisi shows the preservation of an unusual combination of digestive structures: a crop and paired digestive glands along the alimentary tract. This combination of digestive structures has also never been observed in trilobites this old, and is rare in general, with prior evidence of it from one juvenile trilobite specimen from the late Cambrian Orsten fauna of Sweden and possibly one adult trilobite specimen from the Early Ordovician Fezouata Lagerstätte. The variation in the fidelity of preservation of digestive structures within and across different Lagerstätten may be due to variation in the type, quality, and point of digestion of food among specimens in addition to differences in mode of preservation. The presence and combination of these digestive features in the Guanshan trilobites contradicts current models of how the trilobite digestive system was structured and evolved over time. Most notably, the crop is not a derived structure as previously proposed, although it is possible that the relative size of the crop increased over the evolutionary history of the clade.

Sociodemographic and environmental correlates of active commuting in rural America.

Science.gov (United States)

Fan, Jessie X; Wen, Ming; Kowaleski-Jones, Lori

2015-01-01

This research investigated participation rates in 3 modes of active commuting (AC) and their sociodemographic and physical environmental correlates in rural America. The 2000 Census supplemented with other data sets were used to analyze AC rates in percentage of workers walking, biking, and taking public transportation to work in 14,209 nonmetropolitan rural tracts identified by RUCA codes, including 4,067 small rural and 10,142 town-micropolitan rural tracts. Sociodemographic and physical environmental variables were correlated with 3 AC modes simultaneously using Seemingly Unrelated Regression for nonmetro rural, and for small rural and town-micropolitan rural separately. The average AC rates in rural tracts were 3.63%, 0.26%, and 0.56% for walking, biking, and public transportation to work, respectively, with small rural tracts having a higher rate of walking but lower rates of biking and public transportation to work than town-micropolitan tracts. In general, better economic well-being was negatively associated with AC but percentage of college-educated was a positive correlate. Population density was positively associated with AC but greenness and proximity to parks were negative correlates. However, significant differences existed for different AC modes, and between small rural and town-micropolitan rural tracts. Sociodemographic factors explained more variance in AC than physical environmental factors but the detailed relationships were complex, varying by AC mode and by degree of rurality. Any strategy to promote AC in rural America needs to be sensitive to the population size of the area and assessed in a comprehensive manner to avoid a "one size fits all" approach. © 2014 National Rural Health Association.

Long-term thermophilic mono-digestion of rendering wastes and co-digestion with potato pulp

Energy Technology Data Exchange (ETDEWEB)

Bayr, S., E-mail: suvi.bayr@jyu.fi; Ojanperä, M.; Kaparaju, P.; Rintala, J.

2014-10-15

Highlights: • Rendering wastes’ mono-digestion and co-digestion with potato pulp were studied. • CSTR process with OLR of 1.5 kg VS/m{sup 3} d, HRT of 50 d was unstable in mono-digestion. • Free NH{sub 3} inhibited mono-digestion of rendering wastes. • CSTR process with OLR of 1.5 kg VS/m{sup 3} d, HRT of 50 d was stable in co-digestion. • Co-digestion increased methane yield somewhat compared to mono-digestion. - Abstract: In this study, mono-digestion of rendering wastes and co-digestion of rendering wastes with potato pulp were studied for the first time in continuous stirred tank reactor (CSTR) experiments at 55 °C. Rendering wastes have high protein and lipid contents and are considered good substrates for methane production. However, accumulation of digestion intermediate products viz., volatile fatty acids (VFAs), long chain fatty acids (LCFAs) and ammonia nitrogen (NH{sub 4}-N and/or free NH{sub 3}) can cause process imbalance during the digestion. Mono-digestion of rendering wastes at an organic loading rate (OLR) of 1.5 kg volatile solids (VS)/m{sup 3} d and hydraulic retention time (HRT) of 50 d was unstable and resulted in methane yields of 450 dm{sup 3}/kg VS{sub fed}. On the other hand, co-digestion of rendering wastes with potato pulp (60% wet weight, WW) at the same OLR and HRT improved the process stability and increased methane yields (500–680 dm{sup 3}/kg VS{sub fed}). Thus, it can be concluded that co-digestion of rendering wastes with potato pulp could improve the process stability and methane yields from these difficult to treat industrial waste materials.

The foodomics approach for the evaluation of protein bioaccessibility in processed meat upon in vitro digestion.

Science.gov (United States)

Bordoni, Alessandra; Laghi, Luca; Babini, Elena; Di Nunzio, Mattia; Picone, Gianfranco; Ciampa, Alessandra; Valli, Veronica; Danesi, Francesca; Capozzi, Francesco

2014-06-01

The present work describes a foodomics protocol coupling an in vitro static simulation of digestion to a combination of omics techniques, to grant an overview of the protein digestibility of a meat-based food, namely Bresaola. The proteolytic activity mediated by the digestive enzymes is evaluated through Bradford and SDS-PAGE assays, combined to NMR relaxometry and spectroscopy, to obtain information ranging from the microscopic to the molecular level, respectively. The simple proteomics tool adopted here points out that a clear increase of bioaccessible proteins occurs in the gastric phase, rapidly disappearing during the following duodenal digestion. However, SDS-PAGE and the Bradford assay cannot follow the fate of the digested proteins when the products are sized meat matrix. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Digested disorder, Quarterly intrinsic disorder digest (October-November-December, 2013).

Science.gov (United States)

DeForte, Shelly; Reddy, Krishna D; Uversky, Vladimir N

2015-01-01

This is the 4th issue of the Digested Disorder series that represents reader's digest of the scientific literature on intrinsically disordered proteins. The only 2 criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the fourth quarter of 2013; i.e. during the period of October, November, and December of 2013. Similar to previous issues, the papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings.

In vitro digestion and physicochemical characteristics of corn starch mixed with amino acid modified by low pressure treatment.

Science.gov (United States)

Ji, Ying

2018-03-01

The digestibility and molecular structure of corn starch mixed with amino acid modified by low-pressure treatment (LPT) was investigated. Amino acid induced a significant increase in the slowly digestible starch (SDS) and decrease in the rapidly digestible starch (RDS) after LPT. The reason is the formation of ester bond between the molecular chains of amino acid and starch. Low pressure treatment altered greatly the morphology of corn starch mixed with or without amino acid. After LPT, less ordered Maltese and more granule fragments were observed for starch-amino acid complex. An increase in size distribution was obvious after LPT and the size distribution curves provided from a new variety. We found that higher enthalpy and relative crystallinity of the starch-amino acid complex were associated with a higher SDS content. It can be inferred that LPT had a greater impact on the digestion and structural characterization of corn starch mixed with amino acids. Copyright © 2017 Elsevier Ltd. All rights reserved.

All Rural Places Are Not Created Equal: Revisiting the Rural Mortality Penalty in the United States

Science.gov (United States)

2014-01-01

Objectives. I investigated mortality disparities between urban and rural areas by measuring disparities in urban US areas compared with 6 rural classifications, ranging from suburban to remote locales. Methods. Data from the Compressed Mortality File, National Center for Health Statistics, from 1968 to 2007, was used to calculate age-adjusted mortality rates for all rural and urban regions by year. Criteria measuring disparity between regions included excess deaths, annual rate of change in mortality, and proportion of excess deaths by population size. I used multivariable analysis to test for differences in determinants across regions. Results. The rural mortality penalty existed in all rural classifications, but the degree of disparity varied considerably. Rural–urban continuum code 6 was highly disadvantaged, and rural–urban continuum code 9 displayed a favorable mortality profile. Population, socioeconomic, and health care determinants of mortality varied across regions. Conclusions. A 2-decade long trend in mortality disparities existed in all rural classifications, but the penalty was not distributed evenly. This constitutes an important public health problem. Research should target the slow rates of improvement in mortality in the rural United States as an area of concern. PMID:25211763

Digested disorder: Quarterly intrinsic disorder digest (April-May-June, 2013).

Science.gov (United States)

DeForte, Shelly; Reddy, Krishna D; Uversky, Vladimir N

2013-01-01

The current literature on intrinsically disordered proteins is overwhelming. To keep interested readers up to speed with this literature, we continue a "Digested Disorder" project and represent a series of reader's digest type articles objectively representing the research papers and reviews on intrinsically disordered proteins. The only 2 criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the period of April, May, and June of 2013. The papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings.

Urbanization disrupts latitude-size rule in 17-year cicadas.

Science.gov (United States)

Beasley, DeAnna E; Penick, Clint A; Boateng, Nana S; Menninger, Holly L; Dunn, Robert R

2018-03-01

Many ectotherms show a decrease in body size with increasing latitude due to changes in climate, a pattern termed converse Bergmann's rule. Urban conditions-particularly warmer temperatures and fragmented landscapes-may impose stresses on development that could disrupt these body size patterns. To test the impact of urbanization on development and latitudinal trends in body size, we launched a citizen science project to collect periodical cicadas ( Magicicada septendecim ) from across their latitudinal range during the 2013 emergence of Brood II. Periodical cicadas are long-lived insects whose distribution spans a broad latitudinal range covering both urban and rural habitats. We used a geometric morphometric approach to assess body size and developmental stress based on fluctuating asymmetry in wing shape. Body size of rural cicadas followed converse Bergmann's rule, but this pattern was disrupted in urban habitats. In the north, urban cicadas were larger than their rural counterparts, while southern populations showed little variation in body size between habitats. We detected no evidence of differences in developmental stress due to urbanization. To our knowledge, this is the first evidence that urbanization disrupts biogeographical trends in body size, and this pattern highlights how the effects of urbanization may differ over a species' range.

Digested disorder: Quarterly intrinsic disorder digest (July-August-September, 2013).

Science.gov (United States)

Reddy, Krishna D; DeForte, Shelly; Uversky, Vladimir N

2014-01-01

The current literature on intrinsically disordered proteins grows fast. To keep interested readers up to speed with this literature, we continue a "Digested Disorder" project and represent a new issue of reader's digest of the research papers and reviews on intrinsically disordered proteins. The only 2 criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the third quarter of 2013; i.e., during the period of June, July, and September of 2013. Similar to previous issues, the papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings.

Rural Credit in Vietnam

DEFF Research Database (Denmark)

Barslund, Mikkel Christoffer; Tarp, Finn

This paper uses a survey of 932 rural households to uncover how the rural credit market operates in four provinces of Vietnam. Households obtain credit through formal and informal lenders, but formal loans are almost entirely for production and asset accumulation. Interest rates fell from 1997...... to 2002, reflecting increased market integration; but the determinants of formal and informal credit demand are distinct. Credit rationing depends on education and credit history, but we find no evidence of a bias against women. Regional differences are striking, and a ‘one size fits all’ approach...... to credit policy is clearly inappropriate....

A high-throughput assay for quantifying appetite and digestive dynamics

Science.gov (United States)

Guggiana-Nilo, Drago; Soucy, Edward; Song, Erin Yue; Lei Wee, Caroline; Engert, Florian

2015-01-01

Food intake and digestion are vital functions, and their dysregulation is fundamental for many human diseases. Current methods do not support their dynamic quantification on large scales in unrestrained vertebrates. Here, we combine an infrared macroscope with fluorescently labeled food to quantify feeding behavior and intestinal nutrient metabolism with high temporal resolution, sensitivity, and throughput in naturally behaving zebrafish larvae. Using this method and rate-based modeling, we demonstrate that zebrafish larvae match nutrient intake to their bodily demand and that larvae adjust their digestion rate, according to the ingested meal size. Such adaptive feedback mechanisms make this model system amenable to identify potential chemical modulators. As proof of concept, we demonstrate that nicotine, l-lysine, ghrelin, and insulin have analogous impact on food intake as in mammals. Consequently, the method presented here will promote large-scale translational research of food intake and digestive function in a naturally behaving vertebrate. PMID:26108871

Characterization of biochar prepared from biogas digestate.

Science.gov (United States)

Hung, Chao-Yi; Tsai, Wen-Tien; Chen, Jie-Wei; Lin, Yu-Quan; Chang, Yuan-Ming

2017-08-01

In the study, the biogas digestate was evaluated as a potential feedstock for preparing biochars at a broad temperature range of 300-900°C. The physico-chemical and pore properties of the resulting biochars (denoted as SDBC, solid digestate biochar), including calorific value (higher heating value), surface area/pore volume/pore size distribution, true density, scanning electron microscopy - energy dispersive X-ray spectroscopy (SEM-EDS) and X-ray powder diffraction (XRD), were studied. It was found that the higher heating values of the SDBC products were on a decreasing trend as pyrolysis temperature increased, but they indicated an increase in true density. The results are probably associated with the active pyrolysis of the lignocellulosic fragments and the calcination (or shrinkage) processes, thus resulting in the increased contents of aromatic carbon clusters and main mineral constituents remained. Based on the pore properties, pyrolysis temperature at around 800°C seemed to be the optimal condition for producing SDBC, where its Brunauer-Emmet-Teller (BET) surface area (>100m 2 /g) largely increased as compared to that of the digestate feedstock (700°C) due to the high aromaticity via the thermal decomposition of lignocelluloses and the volatilization of inorganic minerals. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evaluation of the pepsin digestibility assay for predicting amino acid digestibility of meat and bone meals.

Science.gov (United States)

Davis, T M; Parsons, C M; Utterback, P L; Kirstein, D

2015-05-01

Sixteen meat and bone meal (MBM) samples were obtained and selected from various company plants to provide a wide range in pepsin nitrogen digestibility values. Pepsin digestibility was determined using either 0.02 or 0.002% pepsin. Amino acid (AA) digestibility of the 16 MBM samples was then determined using a precision-fed cecectomized rooster assay. The 0.02% pepsin digestibility values were numerically higher than the 0.002% pepsin values. The values varied from 77 to 93% for 0.02% pepsin and from 67 to 91% for 0.002% pepsin. The rooster AA digestibility results showed a wide range of values among MBM samples mostly due to the 4 samples having lowest and highest AA digestibility. A precision-fed broiler chick ileal AA digestibility assay confirmed that there were large differences in AA digestibility among the MBM samples having the lowest and highest rooster digestibility values. Correlation analyses between pepsin and AA digestibility values showed that the correlation values (r) were highly significant (P digestibility values were not included in the correlation analyses, the correlation coefficient values (r) were generally very low and not significant (P > 0.05). The results indicated that the pepsin nitrogen digestibility assay is only useful for detecting large differences in AA digestibility among MBM. There also was no advantage for using 0.02 versus 0.002% pepsin. © 2015 Poultry Science Association Inc.

Enhanced dewaterability of sludge during anaerobic digestion with thermal hydrolysis pretreatment: New insights through structure evolution.

Science.gov (United States)

Zhang, Jingsi; Li, Ning; Dai, Xiaohu; Tao, Wenquan; Jenkinson, Ian R; Li, Zhuo

2017-12-19

Comprehensive insights into the sludge digestate dewaterability were gained through porous network structure of sludge. We measured the evolution of digestate dewaterability, represented by the solid content of centrifugally dewatered cake, in high-solids sequencing batch digesters with and without thermal hydrolysis pretreatment (THP). The results show that the dewaterability of the sludge after digestion was improved by 3.5% (±0.5%) for unpretreated sludge and 5.1% (±0.4%) for thermally hydrolyzed sludge. Compared to the unpretreated sludge digestate, thermal hydrolysis pretreatment eventually resulted in an improvement of dewaterability by 4.6% (±0.5%). Smaller particle size and larger surface area of sludge were induced by thermal hydrolysis and anaerobic digestion treatments. The structure strength and compactness of sludge, represented by elastic modulus and fractal dimension respectively, decreased with increase of digestion time. The porous network structure was broken up by thermal hydrolysis pretreatment and was further weakened during anaerobic digestion, which correspondingly improved the dewaterability of digestates. The logarithm of elastic modulus increased linearly with fractal dimension regardless of the pretreatment. Both fractal dimension and elastic modulus showed linear relationship with dewaterability. The rheological characterization combined with the analysis of fractal dimension of sewage sludge porous network structure was found applicable in quantitative evaluation of sludge dewaterability, which depended positively on both thermal hydrolysis and anaerobic digestion. Copyright © 2017 Elsevier Ltd. All rights reserved.

Digestive Physiology of Octopus maya and O. mimus: Temporality of Digestion and Assimilation Processes

Science.gov (United States)

Gallardo, Pedro; Olivares, Alberto; Martínez-Yáñez, Rosario; Caamal-Monsreal, Claudia; Domingues, Pedro M.; Mascaró, Maite; Sánchez, Ariadna; Pascual, Cristina; Rosas, Carlos

2017-01-01

Digestive physiology is one of the bottlenecks of octopus aquaculture. Although, there are successful experimentally formulated feeds, knowledge of the digestive physiology of cephalopods is fragmented, and focused mainly on Octopus vulgaris. Considering that the digestive physiology could vary in tropical and sub-tropical species through temperature modulations of the digestive dynamics and nutritional requirements of different organisms, the present review was focused on the digestive physiology timing of Octopus maya and Octopus mimus, two promising aquaculture species living in tropical (22–30°C) and sub-tropical (15–24°C) ecosystems, respectively. We provide a detailed description of how soluble and complex nutrients are digested, absorbed, and assimilated in these species, describing the digestive process and providing insight into how the environment can modulate the digestion and final use of nutrients for these and presumably other octopus species. To date, research on these octopus species has demonstrated that soluble protein and other nutrients flow through the digestive tract to the digestive gland in a similar manner in both species. However, differences in the use of nutrients were noted: in O. mimus, lipids were mobilized faster than protein, while in O. maya, the inverse process was observed, suggesting that lipid mobilization in species that live in relatively colder environments occurs differently to those in tropical ecosystems. Those differences are related to the particular adaptations of animals to their habitat, and indicate that this knowledge is important when formulating feed for octopus species. PMID:28620313

Digested BLG can induce tolerance when co-administered with intact BLG in Brown Norway rats

DEFF Research Database (Denmark)

Bøgh, Katrine Lindholm; Barkholt, Vibeke; Madsen, Charlotte Bernhard

the human gastro-duodenal digestion process. Four different fractions of BLG-digest was made, based on sizes of peptides or aggregates hereof. Intact BLG and the four fractions of BLG-digesta were characterized by protein chemical analyses. Brown Norway (BN) rats were immunised i.p. three times without......Background: Milk is a major constituent of small children’s diet. Milk allergy is also one of the most common allergies in small children. Prevention, treatment and general understanding of this allergy are therefore important. Methods: Intact BLG was digested in an in vitro model simulating...... the use of adjuvant with either PBS (control), 200 µg of intact BLG, 30 µg of intact BLG, 200 µg of digested BLG (with 30 µg of intact BLG), 200 µg of digested BLG, 200 µg of a fraction of large complexes or 200 µg of a fraction of small complexes (all three without intact BLG). Sera from BN rats were...

Influence of different pre-treatment routes on the anaerobic digestion of a filamentous algae

DEFF Research Database (Denmark)

Ehimen, Ehiazesebhor Augustine; Holm-Nielsen, Jens Bo; Poulsen, M.

2013-01-01

biomass blending (20% compared to use of a mechanical size reduction method alone. The methane yields from Rhizoclonium biomass were however observed to be considerably lower than those of other algae species from......The anaerobic digestion of outdoor cultivated Rhizoclonium biomass was investigated in this study. The influence of applying mechanical and biological pre-treatment methods prior to the biomass digestion on the overall methane yields was examined. The results show that the application of a combined...

Digestion of thyroglobulin with purified thyroid lysosomes: preferential release of iodoamino acids

International Nuclear Information System (INIS)

Tokuyama, T.; Yoshinari, M.; Rawitch, A.B.; Taurog, A.

1987-01-01

[ 131 I]Thyroglobulin [( 131 I]Tg), prepared by either enzymatic iodination of human goiter Tg in vitro or isolation from the thyroids of rats previously injected with 131 I, was digested with a solubilized enzyme mixture prepared from purified hog thyroid lysosomes. The digestion was performed at 37 C for 24 h under nitrogen at pH 5.0 in the presence of 4 mM dithiothreitol. Under these conditions the release of free [ 131 I] iodoamino acids (MIT, DIT, T4, and T3) was quantitatively very similar to that observed with a standard pronase digestion procedure. To determine whether other amino acids in Tg were released as quantitatively as the iodoamino acids, free amino acids in the lysosomal digest were measured, and total free amino acid release was compared with a similar analysis performed after digestion of [ 131 I]Tg with 6 N HCl. Total amino acid release was much less complete than iodoamino acid release, indicating preferential release of iodoamino acids from Tg by lysosomal digestion. Analysis of the lysosomal digest by HPLC on a size exclusion column indicated that Tg was degraded to peptides with a mol wt less than 4000. Assuming that the in vitro lysosomal digestion system represents a valid model for the physiological proteolytic system that degrades Tg, the results of the present study suggest that a substantial portion of the Tg in the thyroid is not degraded to free amino acids and that peptide fragments of Tg are normally present in the thyroid. In such a case, the fate and possible physiological activity of these fragments require further elucidation

Integration of metabolism and digestion in the hyrax | Fairall | South ...

African Journals Online (AJOL)

Metabolic adaptations and digestive ability were integrated to explain the ecological efficiency of the hyrax (Procavia capensis). Metabolic rate was shown to decrease linearly with a drop in ambient temperature, but at a lower rate than an animal of equivalent size, the guinea-pig (Cavia porcel/us). This is achieved by ...

Rural school in the Tenza Valley, rural education and agroecology reflections on rural “development”

Directory of Open Access Journals (Sweden)

Mejia Alfonso Miguel Fernando

2011-08-01

Full Text Available size: 10pt; mso-fareast-font-family: MinionPro-Regular; mso-fareast-language: EN-US; mso-ansi-language: EN-US; mso-bidi-language: AR-SA;" lang="EN-US">

size: 10pt; mso-fareast-font-family: MinionPro-Regular; mso-ansi-language: EN-US;" lang="EN-US">The municipality of Sutatenza (Boyaca, constitutes an important reference for rural education in Colombia due to “Radio Sutatenza” (Educational Radio and the People’s Cultural Action in the mid-twentieth century. Currently, in the same town, a process called the Campesina Community School del Valle de Tenza has been brewing, under an agroecological approach, guided in its work to the cultural and productive Andean farmers, their families and their young people to cultivate in them a return the field. This article addresses this educational experience for contrasting approaches of “development” with the perceptions and visions that emerge from the rural world, without being radically different, it raises important questions for the call for and controversy of development, from the local.

Fringe Benefits Provision by Rural Small Businesses

OpenAIRE

Jayachandran N. Variyam; David S. Kraybill

1998-01-01

We examine the relationship between employer size and the provision of fringe benefits in a large sample of rural businesses. A clear employer size-benefits relationship exists only in the case of health insurance, while other benefits are not strongly linked to employer size. The negative relationship between employer size and health insurance is weaker, though still existent, in businesses whose employees have relatively high skill levels. Single, independent establishments and sole proprie...

The hydro digest

Energy Technology Data Exchange (ETDEWEB)

Scheil, Hermann [Itaipu Mondig, Power Generation Group (KWU), Siemens AG, Erlangen (Germany)

2000-12-01

Digest WK is an analysis and diagnostics system for turbine generators in large hydroelectric plant: it was developed from the Digest system which has been used in steam turbine plants for many years. The system is in use at the world's biggest hydro plant in Itaipu Binacional between Paraguay and Brazil. The system is described under the sub-headings of (a) monitoring concept; (b) the Digest WK system; (c) vibration monitoring; (d) generator temperature analysis and (e) outlook.

Investigation of digestion Kinetics in commercial starches using in-situ small-angle neutron scattering

International Nuclear Information System (INIS)

Blazek, Jaroslav; Gilbert, Elliot Paul

2009-01-01

Full text: The digestion of starch has been the subject of many investigations, mostly involving in vitro measurement of the susceptibility of starches to attack by different enzymes, rather than measuring actual digestibility in vivo. The rate and extent of amylolytic hydrolysis of granular starches is known to vary according to botanical origin. Granule characteristics considered to influence susceptibility to attack by alpha-amylase include crystallinity, granule size and available specific surface, amylose content, porosity, structural inhomogeneities and degree of integrity. Most in-vitro studies of granular starch digestion have been limited to samples for which aliquots have been removed from the reaction mixture at various time intervals and freeze-dried to be subsequently characterized using a range of techniques. It remains unclear whether sample preparation creates artefacts in the samples. In this study, we have studied the kinetics of starch digestion of several commercial granular starches by time-resolved small-angle neutron scattering using an in-situ digestion chamber allowing, for the first time, to follow structural changes of starch in the course of digestion directly in the digestion mixture. Additionally, samples before and after digestion were studied by x-ray diffraction, small-angle x-ray scattering, differential scanning calorimetry and microscopy. Microscopy revealed that studied starches, which varied in their amylose content and digestion kinetics, followed different modes of attack The multidisciplinary approach allowed the nanostructural changes detected by small-angle scattering in the course of enzymic breakdown to be correlated with changes in crystallinity and functional properties.

Motivations for childbearing and fertility behavior among urban and rural families of Iran.

Science.gov (United States)

Hekmat, F; Kabacoff, R I; Klein, H E

1983-01-01

A sample of 384 husbands and wives were randomly selected and interviewed to investigate the implication of fertility norms and motivations for childbearing on fertility and family planning behavior among Iranian families in urban and rural areas of Iran, after the Islamic Revolution of 1979. The term "fertility behavior" refers to actual family size, which is defined as number of children the respondent has living at the time of the interview. "Family planning behavior" refers to the duration of time that the subject has used any birth control method(s). Rural families demonstrated larger actual and ideal family sizes than urban families. The rural sample had a median actual family size of 3.5 children and a median ideal family size of 4.7 children. For the urban sample these figures were 2.2 and 2.3, respectively. The median number of years married was 12.33 for rural and 13.91 for urban respondents. Urban respondents tended to emphasize the psychological and emotional benefits and liabilities associated with having children while rural respondents tended to emphasize both economic and security related motivations. Both groups endorsed infant mortality as a motivation for having more children. Male and female respondents were remarkably similar in their endorsed motivations. There was a significant positive correlation between desired and ideal family size. The correlations among ideal/desired family size and practicing birth control methods were the same and significant at the .001 level. The relationship between motivations for childbearing and years of practicing birth control methods was also significant at the .001 level. Stepwise regression analyses were performed to examine the important predictors of fertility and family planning behavior. For both actual family size and years on birth control, males and females were very similar in terms of predictor importance. Those respondents with less education and large ideal family size tended to have larger

The Need and Use the Rural ICT Services in Iranian Rural Areas

Directory of Open Access Journals (Sweden)

Amir Mozafar Amini

2015-11-01

Full Text Available Nowadays, Internet access and use of information resources in all human societies are experiencing a rising trend, and different communities are used each with multiple infrastructures due to the benefits of ICT. The present study was based on applied research. In this research, a hybrid approach involving quantitative methods (survey and qualitative (observation, interviews was used. Statistical population of this study consists of two parts, the first part responsible for rural ICT offices, with a population of 125 people using Cochran Formula 80 subjects were selected as first sample, and the second part of the rural of first sample villages with a population of 84,836 people using Cochran formula and randomized-comparative method were studied as second sample. The questionnaire was subjected to reliability testing by using data collection in the pilot study with Cronbach’s Alpha value 0.73 to 0.95 for all variables. SPSS statistical software was used to analysis the data. The results of the study indicate that the overall performance of the agencies providing services to the rural was lower-middle in the offices in banking services has received first place, and the final ranking in the provision of health services. The results of study showed that rural employment, level education and family size effect on the rate of rural ICT offices.

Inside the guts of wood-eating catfishes: can they digest wood?

Science.gov (United States)

German, Donovan P

2009-11-01

To better understand the structure and function of the gastrointestinal (GI) tracts of wood-eating catfishes, the gross morphology, length, and microvilli surface area (MVSA) of the intestines of wild-caught Panaque nocturnus, P. cf. nigrolineatus "Marañon", and Hypostomus pyrineusi were measured, and contrasted against these same metrics of a closely related detritivore, Pterygoplichthys disjunctivus. All four species had anatomically unspecialized intestines with no kinks, valves, or ceca of any kind. The wood-eating catfishes had body size-corrected intestinal lengths that were 35% shorter than the detritivore. The MVSA of all four species decreased distally in the intestine, indicating that nutrient absorption preferentially takes place in the proximal and mid-intestine, consistent with digestive enzyme activity and luminal carbohydrate profiles for these same species. Wild-caught Pt. disjunctivus, and P. nigrolineatus obtained via the aquarium trade, poorly digested wood cellulose (<33% digestibility) in laboratory feeding trials, lost weight when consuming wood, and passed stained wood through their digestive tracts in less than 4 h. Furthermore, no selective retention of small particles was observed in either species in any region of the gut. Collectively, these results corroborate digestive enzyme activity profiles and gastrointestinal fermentation levels in the fishes' GI tracts, suggesting that the wood-eating catfishes are not true xylivores such as beavers and termites, but rather, are detritivores like so many other fishes from the family Loricariidae.

Impact of Protein Gel Porosity on the Digestion of Lipid Emulsions.

Science.gov (United States)

Sarkar, Anwesha; Juan, Jean-Marc; Kolodziejczyk, Eric; Acquistapace, Simone; Donato-Capel, Laurence; Wooster, Tim J

2015-10-14

The present study sought to understand how the microstructure of protein gels impacts lipolysis of gelled emulsions. The selected system consisted of an oil-in-water (o/w) emulsion embedded within gelatin gels. The gelatin-gelled emulsions consisted of a discontinuous network of aggregated emulsion droplets (mesoscale), dispersed within a continuous network of gelatin (microscale). The viscoelastic properties of the gelled emulsions were dominated by the rheological behavior of the gelatin, suggesting a gelatin continuous microstructure rather than a bicontinuous gel. A direct relationship between the speed of fat digestion and gel average mesh size was found, indicating that the digestion of fat within gelatin-gelled emulsions is controlled by the ability of the gel's microstructure to slow lipase diffusion to the interface of fat droplets. Digestion of fat was facilitated by gradual breakdown of the gelatin network, which mainly occurred via surface erosion catalyzed by proteases. Overall, this work has demonstrated that the lipolysis kinetics of gelled emulsions is driven by the microstructure of protein gels; this knowledge is key for the future development of microstructures to control fat digestion and/or the delivery of nutrients to different parts of the gastrointestinal tract.

Bio digester : anaerobic methanogenesis

NARCIS (Netherlands)

Bullema, Marten; Hulzen, Hans; Keizer, Melvin; Pruisscher, Gerlof; Smint, Martin; Vincent, Helene

2014-01-01

As part of the theme 13 and 14, our group have to realize a project in the field of the renewable energy. This project consist of the design of a bio-digester for the canteen of Zernikeplein. Gert Hofstede is our client. To produce energy, a bio-digester uses the anaerobic digestion, which is made

Solid anaerobic digestion batch with liquid digestate recirculation and wet anaerobic digestion of organic waste: Comparison of system performances and identification of microbial guilds.

Science.gov (United States)

Di Maria, Francesco; Barratta, Martino; Bianconi, Francesco; Placidi, Pisana; Passeri, Daniele

2017-01-01

Solid anaerobic digestion batch (SADB) with liquid digestate recirculation and wet anaerobic digestion of organic waste were experimentally investigated. SADB was operated at an organic loading rate (OLR) of 4.55kgVS/m 3 day, generating about 252NL CH 4 /kgVS, whereas the wet digester was operated at an OLR of 0.9kgVS/m 3 day, generating about 320NL CH 4 /kgVS. The initial total volatile fatty acids concentrations for SADB and wet digestion were about 12,500mg/L and 4500mg/L, respectively. There were higher concentrations of ammonium and COD for the SADB compared to the wet one. The genomic analysis performed by high throughput sequencing returned a number of sequences for each sample ranging from 110,619 to 373,307. More than 93% were assigned to the Bacteria domain. Seven and nine major phyla were sequenced for the SADB and wet digestion, respectively, with Bacteroidetes, Firmicutes and Proteobacteria being the dominant phyla in both digesters. Taxonomic profiles suggested a methanogenic pathway characterized by a relevant syntrophic acetate-oxidizing metabolism mainly in the liquid digestate of the SADB. This result also confirms the benefits of liquid digestate recirculation for improving the efficiency of AD performed with high solids (>30%w/w) content. Copyright © 2016 Elsevier Ltd. All rights reserved.

Modelling methane emission mitigation by anaerobic digestion: effect of storage conditions and co-digestion.

Science.gov (United States)

Moset, Veronica; Wahid, R; Ward, A; Møller, H B

2018-03-13

In this work the methane conversion factor (MCF) of untreated and anaerobically digested cattle manure (CM) as a function of storage temperature, time and co-digestion was measured in an in vitro experiment and modelled based on IPCC (2006) methodology (Tier 2). For this, one sample of untreated CM, one sample of mono-digested CM and three samples of CM co-digested with grass were incubated at seven different temperatures (from 5°C to 50°C) over 346 days. The main results showed that ultimate methane yield (B 0 ) of CM is higher than the B 0 reported by the IPCC (2006). Two temperature ranges should be considered for MCF evolution, below 15°C very low MCF was measured in this work for untreated CM, mono and co-digested samples. At higher temperatures, MCF obtained in this work and that provided by the IPCC could be comparable depending on storage time. Anaerobic mono-digestion decreased MCF compared to untreated CM at all temperatures and times, except in the temperature range between 20°C and 25°C if storage time is low, due to a lag phase observed in CM. This lag phase would probably not happen in real storage conditions depending on the proportion of old manure remaining in the storage tank. Co-digestion with grass-decreased MCF compared to mono-digestion, but increased CH 4 production in terms of fresh matter due to the higher B 0 of the mixture. Storage time, temperature and co-digestion should be considered in the quantification of CH 4 emission from digested material.

The challenges of anaerobic digestion and the role of biochar in optimizing anaerobic digestion.

Science.gov (United States)

Fagbohungbe, Michael O; Herbert, Ben M J; Hurst, Lois; Ibeto, Cynthia N; Li, Hong; Usmani, Shams Q; Semple, Kirk T

2017-03-01

Biochar, like most other adsorbents, is a carbonaceous material, which is formed from the combustion of plant materials, in low-zero oxygen conditions and results in a material, which has the capacity to sorb chemicals onto its surfaces. Currently, research is being carried out to investigate the relevance of biochar in improving the soil ecosystem, digestate quality and most recently the anaerobic digestion process. Anaerobic digestion (AD) of organic substrates provides both a sustainable source of energy and a digestate with the potential to enhance plant growth and soil health. In order to ensure that these benefits are realised, the anaerobic digestion system must be optimized for process stability and high nutrient retention capacity in the digestate produced. Substrate-induced inhibition is a major issue, which can disrupt the stable functioning of the AD system reducing microbial breakdown of the organic waste and formation of methane, which in turn reduces energy output. Likewise, the spreading of digestate on land can often result in nutrient loss, surface runoff and leaching. This review will examine substrate inhibition and their impact on anaerobic digestion, nutrient leaching and their environmental implications, the properties and functionality of biochar material in counteracting these challenges. Copyright © 2016 Elsevier Ltd. All rights reserved.

Metionina mais cistina digestível e relação metionina mais cistina digestível: lisina para codornas japonesas Digestible methionine plus cystine and relation digestible methionine plus cystine: lysine for japanese quails

Directory of Open Access Journals (Sweden)

Julio Francisco Valiati Marin

2011-09-01

Full Text Available Objetivou-se determinar o melhor nível de metionina mais cistina digestível e a melhor relação metionina mais cistina digestível:lisina digestível em diferentes níveis de proteína para codorna em postura. Foram utilizadas 400 codornas japonesas produtoras de ovos de consumo com 45 dias de idade, em delineamento inteiramente casualizado, num esquema fatorial 2 x 5, dois níveis de proteína bruta (19,5% e 21,5% e cinco níveis de metionina mais cistina digestível (0,60%; 0,67%; 0,74%; 0,81% e 0,88%, com cinco repetições e oito aves por unidade experimental. Foram analisadas as taxas de postura (%, peso médio dos ovos (g, massa de ovos (g de ovos/ave/dia, consumo de ração (g/ave/dia, conversão alimentar (g de ração/g de ovos, peso e porcentagem de gema (g e %, peso e porcentagem de clara (g e % e peso e porcentagem de casca (g e %. Para o nível de 19,5% de proteína 0,60% de metionina mais cistina digestível e relação metionina mais cistina digestível:lisina digestível de 0,66% foram suficientes para otimizar a produção. Para o nível de 21,5% de proteína 0,851% de metionina mais cistina digestível com relação metionina mais cistina digestível:lisina digestível de 0,935% com consumo diário de 223,3mg/ave levou a uma melhor produção de ovos de codornas.This research had the purpose to determine the best level of digestible methionine plus cystine and the best relation of digestible methionine plus cystine:digestible lysine in different levels of protein for laying Japanese quails. 400 laying Japanese quails, with 45 days of age were used in a completely randomized design, with a factorial 2 x 5, two crude protein levels (19,5% and 21,5% and five levels of digestible methionine plus cystine (0,60%; 0,67%; 0,74%; 0,81% e 0,88%, with five replicates and eight quails per experimental unity. There were analysis of the posture rate (%, egg average weight (g egg mass (egg grams/bird/day, feed intake (g/bird/day, feed

Development of bioenergy technology for rural micro mills production of milk, ice and bio fertilizer; Desenvolvimento de tecnologia de bioenergia rural para micro usinas de producao de leite, gelo e bio fertilizante

Energy Technology Data Exchange (ETDEWEB)

Selvam, Pagandai V. Pannir; Almeida, Louizy Minora C.A. de; Israel, S B.S. , [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Dept. de Engenharia Quimica

2008-07-01

The generation of thermal energy is the great importance for the agribusiness of dairy industry to conservation the quality of milk, taking into account that the electricity is the main source currently used for the thermal energy input. The small agribusiness dairy industry currently practiced in Brazil faces several problems related to the cost of electricity and the distance of rural properties of networks of power. In the current scenario of Brazilian dairy production, there is need for the generation of cold for the milk cooling, and also the heat for the production of hot water around 50 deg C to 60 deg C and also for cleaning of equipment used for milk production and processing. The main objective of this study is the modeling and simulation of integrated recovery process of solid waste, effluents and bioconversion. The specific project objectives are: comparison study of options and technological routes of low cost material for power generation using conventional and innovative digester; study of new technologies in the use of organic waste for anaerobic digestion for biogas and fertilizer production; enabling the use of low cost digesters with appropriate technology and alternative materials (composites); minimize problems such as environmental pollution and shortage of electricity in rural agroindustry related to milk. A system was developed for energy generating based on the work of UNICAMP (Universidade Estadual de Campinas) using the water-water heat pump for simultaneous production of ice for cooling of milk and hot water for cleaning and disinfecting facilities and equipment. The results obtained in this project were done using process simulation software Superpro design. (author)

Actinidin enhances protein digestion in the small intestine as assessed using an in vitro digestion model.

Science.gov (United States)

Kaur, Lovedeep; Rutherfurd, Shane M; Moughan, Paul J; Drummond, Lynley; Boland, Mike J

2010-04-28

This paper describes an in vitro study that tests the proposition that actinidin from green kiwifruit influences the digestion of proteins in the small intestine. Different food proteins, from sources including soy, meat, milk, and cereals, were incubated in the presence or absence of green kiwifruit extract (containing actinidin) using a two-stage in vitro digestion system consisting of an incubation with pepsin at stomach pH (simulating gastric digestion) and then with added pancreatin at small intestinal pH, simulating upper tract digestion in humans. The digests from the small intestinal stage (following the gastric digestion phase) were subjected to gel electrophoresis (SDS-PAGE) to assess loss of intact protein and development of large peptides during the in vitro simulated digestion. Kiwifruit extract influenced the digestion patterns of all of the proteins to various extents. For some proteins, actinidin had little impact on digestion. However, for other proteins, the presence of kiwifruit extract resulted in a substantially greater loss of intact protein and different peptide patterns from those seen after digestion with pepsin and pancreatin alone. In particular, enhanced digestion of whey protein isolate, zein, gluten, and gliadin was observed. In addition, reverse-phase HPLC (RP-HPLC) analysis showed that a 2.5 h incubation of sodium caseinate with kiwifruit extract alone resulted in approximately 45% loss of intact protein.

Digested disorder: Quarterly intrinsic disorder digest (January/February/March, 2013).

Science.gov (United States)

Uversky, Vladimir N

2013-01-01

The current literature on intrinsically disordered proteins is blooming. A simple PubMed search for "intrinsically disordered protein OR natively unfolded protein" returns about 1,800 hits (as of June 17, 2013), with many papers published quite recently. To keep interested readers up to speed with this literature, we are starting a "Digested Disorder" project, which will encompass a series of reader's digest type of publications aiming at the objective representation of the research papers and reviews on intrinsically disordered proteins. The only two criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest covers papers published during the period of January, February and March of 2013. The papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings.

The value of cooperatives in rural electrification

International Nuclear Information System (INIS)

Yadoo, Annabel; Cruickshank, Heather

2010-01-01

The electricity sectors of many developing countries underwent substantial reforms during the 1980s and 1990s, driven by global agendas of privatization and liberalization. However, rural electrification offered little by way of market incentives for profit-seeking private companies and was often neglected. As a consequence, delivery models for rural electrification need to change. This paper will review the experiences of various rural electrification delivery models that have been established in developing countries, including concessionary models, dealership approaches and the strengthening of small and medium-sized energy businesses. It will use examples from the USA, Bangladesh and Nepal, together with a detailed case study of a Nepali rural electric cooperative, to explore the role that local cooperatives can play in extending electricity access. It is shown that although there is no magic bullet solution to deliver rural electrification, if offered appropriate financial and institutional support, socially orientated cooperative businesses can be a willing, efficient and effective means of extending and managing rural electricity services. It is expected that this paper will be of particular value to policy-makers, donors, project planners and implementers currently working in the field of rural electrification.

Digestibility of nutrients and aspects of the digestive physiology of ...

African Journals Online (AJOL)

The greater cane rat, Thryonomys swinderianus, utilizes high fibrous plant material and is an important meat source in West Africa. An insight in its digestive physiology will enhance our understanding of its feeding habits. Digestibility coefficients of the food were determined during two seasons before the animals were ...

Improved biogas production and biodegradation of oilseed rape straw by using kitchen waste and duck droppings as co-substrates in two-phase anaerobic digestion

Science.gov (United States)

Wang, Chuqiao; Hong, Feng; Lu, Yong; Liu, Hengming

2017-01-01

Oilseed rape straw (ORS) is a kind of biorefractory waste widely existing in the rural area of China, which is highly suitable to mix with kitchen waste (KW) and duck droppings (DD) in two-phase anaerobic digestion (AD). This research introduced the importance of KW and DD addition to improve the biogas production and biodegradation of ORS. A set of comparative experiments were conducted on two-phase mono- and co-digestion with organic load of 60 g VS/L. The total methane yield (TMY) and the biodegradation of ORS of co-digestions were obviously improving, and the synergistic effect found in the two-phase co-digestions. The optimum mixing ratio of ORS, KW and DD was 50:40:10, and the corresponding TMY and VS degradation rate of ORS were 374.5 mL/g VS and 49.7%, respectively. Addition of KW and DD maintained the pH within the optimal range for the hydrolyzing-acidification, improved the phase separation and buffering capacity of AD system. PMID:28767709

The impacts of hammer-mill screen size and grain particle size on the performance of broiler chickens offered diets based on two red sorghum varieties.

Science.gov (United States)

Selle, P H; Truong, H H; Khoddami, A; Moss, A F; Roberts, T H; Liu, S Y

2016-12-12

1. The two red grain sorghums were extensively characterised. Kafirin, polyphenolic compounds, free, conjugated and bound phenolic acids, phytate concentrations and starch pasting profiles were determined. 2. The experiment consisted of a 2 × 4 factorial array of dietary treatments comprising two red sorghum varieties (Tiger and Block I) ground through 4 hammer-mill screen sizes (2.0, 3.2, 4.8 6.0 mm) prior to incorporation into nutritionally equivalent diets. Eight steam-pelleted dietary treatments were each offered to 7 replicates (6 male Ross 308 birds per cage) from 7 to 28 d post-hatch. 3. Effects of dietary treatments on growth performance, relative gizzard and pancreas weights, nutrient utilisation, apparent starch and protein (N) digestibility coefficients and disappearance rates from 4 small intestinal segments were determined. 4. The 2.0-mm hammer-mill screen generated an average geometric mean particle size of 794 μm and the 6.0-mm screen a mean particle size of 1405 μm. However, hammer-mill screen size did not influence weight gain or FCR. The 6.0-mm screen size generated significantly higher starch and protein (N) digestibility coefficients in the distal jejunum and distal ileum than the 2.0-mm hammer-mill screen. 5. Tiger sorghum was superior to Block I sorghum, as significant advantages were observed for feed conversion ratios (3.25%), AME (0.37 MJ), ME:GE ratios (4.15%), AMEn (0.53 MJ), distal ileal starch digestibility coefficients (2.46%) and protein (N) digestibility coefficients in the distal jejunum (4.66%), proximal ileum (1.96%) and distal ileum (2.16%). The inferior Block I sorghum contained more kafirin (67.1 versus 51.3 g/kg), phytate (9.79 versus 8.40 g/kg), total phenolic compounds (4.68 versus 4.12 mg GAE/g), flavan-4-ols (7.98 versus 5.04 ABS/ml/g), total phenolic acids (554 versus 402 μg/g) and total ferulic acid (375 versus 281 μg/g) in comparison to Tiger sorghum.

Smoking and Your Digestive System

Science.gov (United States)

... it Works Zollinger-Ellison Syndrome Smoking and the Digestive System Smoking affects the entire body, increasing the ... caused by cigarette smoking. 2 What is the digestive system? The digestive system is made up of ...

Co-digestion to support low temperature anaerobic pretreatment of municipal sewage in a UASB-digester.

Science.gov (United States)

Zhang, Lei; Hendrickx, Tim L G; Kampman, Christel; Temmink, Hardy; Zeeman, Grietje

2013-11-01

The aim of this work was to demonstrate that co-digestion improves soluble sewage COD removal efficiency in treatment of low temperature municipal sewage by a UASB-digester system. A pilot scale UASB-digester system was applied to treat real municipal sewage, and glucose was chosen as a model co-substrate. Co-substrate was added in the sludge digester to produce additional methanogenic biomass, which was continuously recycled to inoculate the UASB reactor. Soluble sewage COD removal efficiency increased from 6 to 23%, which was similar to its biological methane potential (BMP). Specific methanogenic activity of the UASB and of the digester sludge at 15°C tripled to a value respectively of 43 and 39 mg CH4-COD/(g VSS d). Methane production in the UASB reactor increased by more than 90% due to its doubled methanogenic capacity. Therefore, co-digestion is a suitable approach to support a UASB-digester for pretreatment of low temperature municipal sewage. Copyright © 2013 Elsevier Ltd. All rights reserved.

The in vitro digestibility of beef varies with its inherent ultimate pH.

Science.gov (United States)

Farouk, Mustafa M; Wu, Guojie; Frost, Deborah A; Clerens, Stefan; Knowles, Scott O

2014-11-01

Animal carcasses and cuts of meat are usually differentiated and valued according to size and compositional attributes. An underappreciated variable of red meat is its inherent ultimate pH (pHu) value, which affects organoleptic and processing characteristics. This study tests the hypothesis that high pHu aged meat would be more digestible than low pHu unaged (fresh) meat. Longissimus dorsi muscles collected from 59 bull carcasses had pHu values of 5.6-6.9. These were aged for 21 days at -1.5 °C, then raw and cooked (72 °C) samples were enzymatically digested at 37 °C with pepsin (pH 1.9 for 90 min) followed by pancreatin (pH 8.0 for an additional 120 min) to simulate conditions in the stomach and small intestine, respectively. Meat proteins and peptides in the digests were separated by 1D SDS PAGE. Regardless of pHu, ageing or cooking, most sarcoplasmic and myofibrillar proteins were rapidly digested by pepsin, with concomitant release of products identified by LC-MS/MS as mainly myosin-1, -2 and -7, α-actinin-2 or -3 and tropomyosin beta and alpha chains. These products were resistant to further digestion for the entire 210 min duration of the incubation. In terms of rate and extent of digestibility of these resistant products, high pHu > low pHu (P unaged (P meat samples increased with increasing pHu (P meat was highly digestible but could be further differentiated on the basis of its pHu and the ease of digestibility of proteins. Specific carcasses or cuts could be targeted to consumer groups in order to provide benefits and add value.

Ideal family size in a rural Tswana population | De Villiers | South ...

African Journals Online (AJOL)

A questionnaire was used to discover what 350 rural Tswanas believed the ideal number of children to be; results were tabulated according to age and sex. It appears· that older people tend to want more children and, more surprisingly, that men and women agree on the ideal number of children in a family; this is contrary to ...

Laboratory scale studies on the mesophilic anaerobic digestion of cheese whey in different digester configurations

Energy Technology Data Exchange (ETDEWEB)

Lo, K.V.; Liao, P.H.

1988-02-01

A two-phase system consisting of two reactors in series was used to study the mesophilic anaerobic digestion of cheese whey. A completely-mixed reactor and an anaerobic rotating biological contact reactor were used in series. The results indicated that ethanol and volatile fatty acids were the major products in the first reactor. Acidogenic pretreatment prior to the methanogenic phase resulted in an increase in methane production in the second reactor over that in one-stage digestion. High treatment efficiency in terms of reduction of chemical oxygen demand was also obtained for the two-phase digestion than that of the one-stage digestion. When comparing the system's performance in terms of methane production rate, the two-phase digestion had no advantage over the one-stage digestion.

Treatment of melanoidin wastewater by anaerobic digestion and coagulation.

Science.gov (United States)

Arimi, Milton M; Zhang, Yongjun; Götz, Gesine; Geißen, Sven-Uwe

2015-01-01

Melanoidins are dark-coloured recalcitrant pollutants found in many industrial wastewaters including coffee-manufacturing effluent, molasses distillery wastewater (MDWW) and other wastewater with molasses as the raw material. The wastewaters are mostly treated with anaerobic digestion after some dilution to minimize the inhibition effect. However, the dark colour and recalcitrant dissolved organic carbon (DOC) mainly caused by melanoidin are not effectively removed. The aim of this study was to investigate the removal of colour and remnant DOC by different coagulants from anaerobically digested MDWW. From the six coagulants tested, ferric chloride had the highest melanoidin (48%), colour (92.7%) and DOC (63.3%) removal at pH 5 and a dosage of 1.6 g/l. Both polymer and inorganic salt coagulants tested had optimal colour, melanoidin and DOC removal at acidic pH. The molecular size distribution of synthetic melanoidins by liquid chromatography-organic carbon detection indicated a preferential removal of high-molecular-weight melanoidins over low weight melanoidins by the coagulation. Further studies should focus on how to improve biodegradability of the treated effluent for it to be reused as dilution water for anaerobic digestion.

THE RURAL TOURISM IN DANUBE DELTA

Directory of Open Access Journals (Sweden)

Ionica SOARE

2014-06-01

Full Text Available Purpose - the purpose of this paper is to evaluate the rural areas has market size and forecast its development as an economic activity. The present paper aims at analyzing the rural areas has in Danube Delta. In an enviable BAs which have responsibility for their particular isolated, such as the Danube Delta and the Danube that used, fishing and rural areas has the main activities that provide jobs and income sources for local populations. Design/methodology/approach - A survey was administered to customers’ rural hostel accommodation in Danube Delta. Descriptive statistics method was mainly adopted to calculate the mean with standard deviation of entry assumes variable, and to examine the different levels of consumers' awareness. The index values of product familiarity, the ratio between entries assumes product's familiarity value and the average value. Findings - the research results show hash has rural consumers have different perception and accomplished through behaviour. The information channels of brand hash mainly from friends, relatives and neighbours, so word of mouth spreading is very important for a brand. Women show a higher sensitivity in health and are currently operating the propensity than referred to follow the recommendations for nutrition. Research limitations/implications - This item is intended to synthesize developments and challenges," on June 13th rural market growth has. The results of this paper should be considered tentatively until has also features replicated by larger has rural consumers. Originality/value - members of rural areas has consumer's behavior would improve marketing and the development of rural areas has products, in order to reduce consumer confusion.

Anaerobic digestion of agricultural wastes

Energy Technology Data Exchange (ETDEWEB)

Hobson, P N

1984-01-01

Farm digesters can operate satisfactorily and have a useful role on the farm. Gas production from the farm digester treating animal slurries could be boosted by adding silage liquid, old potatoes, waste cabbages and other crop wastes to the slurry, although the energy economics of maceration have not been calculated. Pollution control and types of digester are discussed. Uses of digested slurry other than for fertilizers are being tested - as protein supplement to farm animal feeds, silage making, hydroponics, fish farming and growing of worms on algae. Overall, digestion could be a contributor to power requirements especially in countries with high all year round crop production.

Acid digestion of geological and environmental samples using open-vessel focused microwave digestion.

Science.gov (United States)

Taylor, Vivien F; Toms, Andrew; Longerich, Henry P

2002-01-01

The application of open vessel focused microwave acid digestion is described for the preparation of geological and environmental samples for analysis using inductively coupled plasma-mass spectrometry (ICP-MS). The method is compared to conventional closed-vessel high pressure methods which are limited in the use of HF to break down silicates. Open-vessel acid digestion more conveniently enables the use of HF to remove Si from geological and plant samples as volatile SiF4, as well as evaporation-to-dryness and sequential acid addition during the procedure. Rock reference materials (G-2 granite, MRG-1 gabbros, SY-2 syenite, JA-1 andesite, and JB-2 and SRM-688 basalts) and plant reference materials (BCR and IAEA lichens, peach leaves, apple leaves, Durham wheat flour, and pine needles) were digested with results comparable to conventional hotplate digestion. The microwave digestion method gave poor results for granitic samples containing refractory minerals, however fusion was the preferred method of preparation for these samples. Sample preparation time was reduced from several days, using conventional hotplate digestion method, to one hour per sample using our microwave method.

Processing traits and digestibility of extruded dog foods with soy protein concentrate.

Science.gov (United States)

Venturini, K S; Sarcinelli, M F; Baller, M A; Putarov, T C; Malheiros, E B; Carciofi, A C

2018-04-11

Soya bean protein concentrate (SPC) with two particle sizes were evaluated on extrusion parameters, kibble formation, digestibility and palatability of dog foods. Eight diets were extruded: PBM-control diet based on poultry by-product meal (PBM); GM-a diet in which corn gluten meal (GM) replaced 45% of the diet protein; cSPC15%, cSPC30% and cSPC45%-diets in which SPC of coarse particle size (600 μm) replaced 15%, 30% and 45% of the diet protein; and sSPC15%, sSPC30% and sSPC45%-diets in which SPC of small particle size (200 μm) replaced 15%, 30% and 45% of the diet protein. The digestibility of nutrients was evaluated for the PBM, GM, cSPC45% and sSPC45% diets, using six dogs per food. The PBM, GM and cSPC45% diets were compared for palatability. Data were submitted for analysis of variance, and the means were compared by polynomial contrasts or Tukey's test (p beans resulted in an ingredient with low fermentable fibre content, which did not alter faecal formation or characteristics. © 2018 Blackwell Verlag GmbH.

Touching the Past, Enroute to the Future: Cultural Journalism in the Curriculum of Rural Schools. ERIC Digest.

Science.gov (United States)

Olmstead, Kathryn

This digest describes the development of cultural journalism and its place in the contemporary curriculum. In the field of cultural journalism, the traditional skills and values of many different groups are chronicled, defined, for example, by ethnic origin, origin, occupation, or environment. The term "cultural journalism" was first…

Effects of size and thermophilic pre-hydrolysis of banana peel during anaerobic digestion, and biomethanation potential of key tropical fruit wastes.

Science.gov (United States)

Odedina, Mary Jesuyemi; Charnnok, Boonya; Saritpongteeraka, Kanyarat; Chaiprapat, Sumate

2017-10-01

Methane production potential of tropical fruit wastes, namely lady-finger banana peel, rambutan waste and longan waste were compared using BMP assay and stoichiometric modified Buswell and Mueller equation. Methane yields based on volatile solid (VS) were in the order of ground banana peel, chopped banana peel, chopped longan waste, and chopped rambutan waste (330.6, 268.3, 234.6 and 193.2 mLCH 4 /gVS) that corresponded to their calculated biodegradability. In continuous operations of banana peel digestion at feed concentrations based on total solid (TS) 1-2%, mesophilic single stage digester run at 20-day hydraulic retention time (20-day HRT) failed at 2%TS, but successfully recovered at 1.5%TS. Pre-hydrolysis thermophilic reactor (4-d HRT) was placed as pre-treatment to mesophilic reactor (20-d HRT). Higher biogas (with an evolution of H 2 ) and energy yields were obtained and greater system stability was achieved over the single stage digestion, particularly at higher solid feedstock. The best performance of two stage digestion was 68.5% VS destruction and energy yield of 2510.9kJ/kgVS added at a feed concentration of 2%TS. Copyright © 2017 Elsevier Ltd. All rights reserved.

Developing a Family-Size Biogas-Fueled Electricity Generating System

OpenAIRE

Haryanto, Agus; Marotin, Fadli; Triyono, Sugeng; Hasanudin, Udin

2017-01-01

The purpose of this study is to develop a family-size biogas-fueled electricity generating system consisting of anaerobic digester, bio-filter scrubber, and power generating engine. Biogas was produced from a pilot scale wet anaerobic digester (5-m3 capacity). The biogas was filtered using bio-scrubber column filled with locally made compost to reduce hydrogen sulfide (H2S) content. Biogas composition was analysed using a gas chromatograph and its H2S level was measured using a H2S detector. ...

The Rural Inpatient Mortality Study: Does Urban-Rural County Classification Predict Hospital Mortality in California?

Science.gov (United States)

Linnen, Daniel T; Kornak, John; Stephens, Caroline

2018-03-28

Evidence suggests an association between rurality and decreased life expectancy. To determine whether rural hospitals have higher hospital mortality, given that very sick patients may be transferred to regional hospitals. In this ecologic study, we combined Medicare hospital mortality ratings (N = 1267) with US census data, critical access hospital classification, and National Center for Health Statistics urban-rural county classifications. Ratings included mortality for coronary artery bypass grafting, stroke, chronic obstructive pulmonary disease, heart attack, heart failure, and pneumonia across 277 California hospitals between July 2011 and June 2014. We used generalized estimating equations to evaluate the association of urban-rural county classifications on mortality ratings. Unfavorable Medicare hospital mortality rating "worse than the national rate" compared with "better" or "same." Compared with large central "metro" (metropolitan) counties, hospitals in medium-sized metro counties had 6.4 times the odds of rating "worse than the national rate" for hospital mortality (95% confidence interval = 2.8-14.8, p centers may contribute to these results, a potential factor that future research should examine.

Chemical Composition, Starch Digestibility and Antioxidant Capacity of Tortilla Made with a Blend of Quality Protein Maize and Black Bean

Directory of Open Access Journals (Sweden)

Luis A. Bello-Pérez

2011-12-01

Full Text Available Tortilla and beans are the basic components in the diet of people in the urban and rural areas of Mexico. Quality protein maize is suggested for tortilla preparation because it presents an increase in lysine and tryptophan levels. Beans contain important amounts of dietary fiber. The objective of this study was to prepare tortilla with bean and assesses the chemical composition, starch digestibility and antioxidant capacity using a quality protein maize variety. Tortilla with bean had higher protein, ash, dietary fiber and resistant starch content, and lower digestible starch than control tortilla. The hydrolysis rate (60 to 50% and the predicted glycemic index (88 to 80 of tortilla decreased with the addition of bean in the blend. Extractable polyphenols and proanthocyanidins were higher in the tortilla with bean than control tortilla. This pattern produced higher antioxidant capacity of tortilla with bean (17.6 μmol Trolox eq/g than control tortilla (7.8 μmol Trolox eq/g. The addition of bean to tortilla modified the starch digestibility and antioxidant characteristics of tortilla, obtaining a product with nutraceutical characteristics.

Effect of fiber source on cell wall digestibility and rate of passage in rabbits.

Science.gov (United States)

García, J; Carabaño, R; de Blas, J C

1999-04-01

The influence of fiber source on fiber digestion and mean retention time was investigated. Six fibrous feedstuffs with wide differences in chemical composition and particle size were selected: paprika meal, olive leaves, alfalfa hay, soybean hulls, sodium hydroxide-treated barley straw, and sunflower hulls. Six diets were formulated to contain one of these ingredients as the sole source of fiber. To avoid nutrient imbalances, fiber sources were supplemented with different proportions of a concentrate free of fiber based on soy protein isolate, wheat flour, lard, and a vitamin and mineral mix to obtain diets containing at least 18.5% CP and 5% starch. Fecal apparent digestibility of nonstarch polysaccharides (NSPd) and its monomers, NDF, NDF-ADL, and ADF-ADL, were determined using four New Zealand White x California growing rabbits per diet. Total, ileorectal, and cecal mean retention times (tMRT, i-rMRT, and cMRT, respectively) were determined for diets based on paprika meal, olive leaves, soybean hulls, and sunflower hulls in 16 does (four per diet) fitted with T-cannulas at the terminal ileum. In both trials, DMI was negatively correlated with the proportion of fine particles (FP: 1.25 mm) (P lignification of NDF, considering lignin as the difference between ADL and acid detergent cutin, was only included as the third variable for the model of NDF digestibility. Digestibility of NSP was positively correlated with those of NDF, NDF-ADL, and ADF-ADL (r = .82, .87 and .85, respectively, P < .001); the latter was also highly correlated with the digestibility of the glucose included in the NSP fraction (r = .86; P < .001). Cecal mean retention time accounted for 63% of average tMRT, for most of the variability in tMRT (r = .99; P < .001), and was positively related to NSPd (r = .89; P < .001). From these results, we conclude that particle size is a major factor affecting fiber digestion efficiency, rate of passage, and feed intake in rabbits.

Rural Neighborhood Walkability: Implications for Assessment.

Science.gov (United States)

Kegler, Michelle C; Alcantara, Iris; Haardörfer, Regine; Gemma, Alexandra; Ballard, Denise; Gazmararian, Julie

2015-06-16

Physical activity levels, including walking, are lower in the southern U.S., particularly in rural areas. This study investigated the concept of rural neighborhood walkability to aid in developing tools for assessing walkability and to identify intervention targets in rural communities. Semi-structured interviews were conducted with physically active adults (n = 29) in rural Georgia. Mean age of participants was 55.9 years; 66% were male, 76% were white, and 24% were African American. Participants drew maps of their neighborhoods and discussed the relevance of typical domains of walkability to their decisions to exercise. Comparative analyses were conducted to identify major themes. The majority felt the concept of neighborhood was applicable and viewed their neighborhood as small geographically (less than 0.5 square miles). Sidewalks were not viewed as essential for neighborhood-based physical activity and typical destinations for walking were largely absent. Destinations within walking distance included neighbors' homes and bodies of water. Views were mixed on whether shade, safety, dogs, and aesthetics affected decisions to exercise in their neighborhoods. Measures of neighborhood walkability in rural areas should acknowledge the small size of self-defined neighborhoods, that walking in rural areas is likely for leisure time exercise, and that some domains may not be relevant.

Determination of digestible and metabolizable energy of fishmeal and soybean meal in rainbow trout with two different sizes (Oncorhynchus mykiss).

Science.gov (United States)

Allameh, Sayed Kamaleddin; Soofiani, Nasrollah Mahboobi; Pourreza, Javad

2007-10-15

The present research carried out to measure digestible (DE) and Metabolizable Energy (ME) for fishmeal and soybean meal in rainbow trout with two different sizes (120 and 220 g mean body weights). DE and ME are evaluation systems for feedstuffs and also, necessary for diet formulation. The fishes were maintained in metabolic chamber with single ingredient assay of feeding and chromic oxide (Cr2O3) was used as an external marker using total fecal collection method. Gross energy and chromic oxide values measured in feces, fishmeal and soybean meal. The results indicated that DE offishmeal was 3700 and 3591 kcal kg(-1) in 120 and 220 g body weight rainbow trout, respectively. Soybean meal had 3004 and 2889 kcal kg(-1) respectively. Calculated ME from DE were 3204 and 3110 kcal kg(-1) for fishmeal and 2601 and 2502 kcal kg(-1) for soybean meal in 120 and 220 g rainbow trout, respectively. The results showed that rainbow trout can utilize fishmeal more efficiently than soybean meal.

Anaerobic digestion and related best management practices : utilizing life cycle assessment

Energy Technology Data Exchange (ETDEWEB)

Venczel, M.Z. [Clarkson Univ., Potsdam, NY (United States); Powers, S.E. [Clarkson Univ., Potsdam, NY (United States)

2010-07-01

This paper reported on a life cycle assessment (LCA) study that compared the environmental impacts of business-as-usual manure management with those of a manure management operation incorporating anaerobic digestion with combined heat and power generation. The case study was based on a medium sized dairy farm in northern New York State. The study identified the benefits resulting from the displacement of fossil fuels, and reduction of related emissions. Although anaerobic digestion of dairy manure with energy recovery through biogas combustion is viewed as a positive environmental approach to increase the use of renewable energy, there are potential negative impacts that can counteract the environmental benefits. The negative impacts are associated with emissions of methane and nitrogen species during digestion and after spreading of digester effluent. The environmental impacts and their causes should be evaluated in order to promote best management practices. Knowledge gained from an LCA was used in this study to assess the benefits associated with various management practices. The study showed that the design and construction of biogas systems must minimize the potential for fugitive emissions of biogas that can readily outweigh the benefits associated fossil fuel displacement. The environmental trade-offs associated with various manure management and energy recovery systems were also described.

Self-help initiatives and rural development in Ibesikpo community of ...

African Journals Online (AJOL)

This study investigates the impact of self-help initiatives on rural development in Ibesikpo community of Akwa Ibom State, Nigeria. Self help initiatives were defined in terms of provision of employment, education and health-care. A sample size of 369 rural dwellers was drawn and data were analyzed using simple regression ...

Your Digestive System and How It Works

Science.gov (United States)

... System & How it Works Zollinger-Ellison Syndrome Your Digestive System & How it Works What is the digestive system? The digestive system is made up of ... you eat or drink each day. Why is digestion important? Digestion is important because your body needs ...

United States Nuclear Regulatory Commission Staff Practice and Procedure Digest. Supplement 2 to Digest No. 1

International Nuclear Information System (INIS)

1978-02-01

This is the second in a series of Supplements to the NRC Practice and Procedure Digest. This Supplement updates the Digest by including pertinent Commission, Appeal Board, and Licensing Board rulings for the period April 1, 1977 to September 30, 1977. The Supplement also adds a number of new topics. The Supplement is structured in the same manner as the Digest. For the convenience of users, the text of the Supplement is preceded by an index which lists the Digest topic headings which are supplemented. In using the main Digest, this index to Supplement 2 as well as the index to Supplement 1 should be consulted to assure that the Digest discussion has not been superseded or updated by information in the Supplements

Effect of low solids retention time and focused pulsed pre-treatment on anaerobic digestion of waste activated sludge.

Science.gov (United States)

Lee, Il-Su; Rittmann, Bruce E

2011-02-01

The interacting effects of Focused Pulsed (FP) treatment and solids retention time (SRT) were evaluated in laboratory-scale digesters operated at SRTs of 2-20 days. Anaerobic digestion and methanogenesis of waste activated sludge (WAS) were stable for SRT ≥ 5 days, but the effluent soluble organic compounds increased significantly for SRT=2 days due to a combination of faster hydrolysis kinetics and washout of methanogens. FP treatment increased the CH(4) production rate and TCOD removal efficiency by up to 33% and 18%, respectively, at a SRT of 20 days. These effects were the result of an increase in the hydrolysis rate, since the concentrations of soluble components remained low for SRT ≥ 5 days. Alternately, FP pre-treatment of WAS allowed the same conversion of TCOD to CH(4) with a smaller SRT and digester size: e.g., 40% size savings with a CH(4) conversion of 0.23 g CH(4)-COD/g COD(in). Copyright © 2010 Elsevier Ltd. All rights reserved.

United States Nuclear Regulatory Commission Staff Practice and Procedure Digest. Supplement 3 to Digest No. 1

International Nuclear Information System (INIS)

1978-04-01

This is the third of a series of Supplements to the NRC Practice and Procedure Digest. This Supplement updates the Digest by including pertinent Commission, Appeal Board, and Licensing Board rulings for the period October 1, 1977 to December 31, 1977. The Supplement also adds several new topics. The Supplement is structured in the same manner as the Digest. For the convenience of users, the text of the Supplement is preceded by an index which lists the Digest topic headings which are supplemented. In using the main Digest, this index to Supplement 3 as well as those to Supplements 1 and 2 should be consulted to assure that the Digest discussion has not been superseded or updated by information in the Supplements. Supplement 3 is intended for use as a ''pocket part''. It should be inserted after Supplements 1 and 2, following the main Digest. Notice is hereby given that all disclaimers with respect to content, accuracy and completeness of information, express or implied warranties, and use of or reliance upon information presented, set forth in regard to the Digest itself, are equally applicable to this Supplement

Digestão dos carboidratos de alimentos volumosos em eqüinos Digestion of carbohydrates of forages in horses

Directory of Open Access Journals (Sweden)

Eliane da Silva Morgado

2009-01-01

, peanut forage (Arachis pintoi, desmodio (Desmodium ovalifolium, pigeon pea (Cajanus cajan, lime-yellow pea (Macrotyloma axillare, stylo (Stylosanthes guianensis e coastcross (Cynodon dactylon, evaluated with the mobile nylon bag technique. In assay 2, four horses were allotted to a 4 × 4 Latin Square design and fed with coastcross hay with four different processed forms with the objective of evaluating whether a reduction of the particle size affected the carbohydrate digestibility. Results showed that horses had high digestion of non-fibrous carbohydrate and hydrolysable carbohydrate and rapidly fermentable carbohydrate fractions of forages. Among the forages analyzed, peanut forage, stylo and lime-yellow pea, presented high nutrient digestibility, and the peanut forage nutrients presented digestibility above 70%, demonstrating potential to be used in diets for horses. The coastcross hay processing in different grinding degrees does not affect the fibrous and non-fibrous carbohydrate fractions digestibility. Analysis of fibrous and non-fibrous carbohydrate fractions is a good indicative of nutritional value of feeds, and could be included in the evaluation of the quality of diets for horses.

Benefits of Rural Biogas Implementation to Economy and Environment: Boyolali Case Study

Directory of Open Access Journals (Sweden)

Zakaria Tazi Hnyine

2016-02-01

Full Text Available Selo, a small agricultural-based village in Boyolali, Central-Java, Indonesia has initiated small-scale rural biogas adoption as it presumably reduces the consumption of LPG, firewood, chemical fertilizer and (women’s overall workload, which especially suitable due to the relatively high use of cattle in that area As environmental problems such as global warming from fossil fuel consumption and land degradation from deforestation and overuse of chemical fertilizers, and socio-economic problems as gender empowerment and self-sufficiency are becoming more pressing, it is useful to analyse the benefits of biogas as an alternative renewable energy technology (RET provision in rural areas. This paper aims to assess the benefits of rural biogas adoption from an economic perspective, through calculating the direct and indirect benefits obtained from biogas adoption in Selo. For this, a field survey was carried out in Selo to ask questions to biogas users (N=21 and non-users (N=5 on their energy and fertilizer consumption, as well as emissions reductions resulting from biogas adoption. Based on the analysis, oon average, a household with biogas saves 490 kWh month–1, 20,000 IDR month–1,185 kg CO2e month–1.Chemical fertilizer consumption remains remarkably high, which may due to a lack of awareness on the potential of digester slurry by the farmers, for indeed, reduction of chemical fertilizer use would help address some environmental problems. Biogas quality of one household has also been determined by comparing its heating value to that of methane; the methane percentage (MP was approximately 31%. The quality is considerably lower than expected from the literature (i.e. around 60%, which may be due to the farmers neither mixing nor supplying water to the dung. Trainings providing methods for improving digester overall effectiveness to particularly the women-folk may enhance digester management and thus biogas production, as they form the main

A life cycle perspective on land use and project economics of electricity from wind and anaerobic digestion

International Nuclear Information System (INIS)

Ciliberti, Carlo; Jordaan, Sarah M.; Smith, Stephen V.; Spatari, Sabrina

2016-01-01

Feed-in tariffs and Renewable Portfolio Standards (RPS) are among the most prominent policies to address anthropogenic influence on climate change. Implementation of RPS favorably affects renewable energy supply and rural development while reducing the land available for meeting demand for food and feed resulting from global population growth. Even in the vast Great Plains of the United States, land requirements are primary considerations between increasing renewable energy capacity and food and feed production. This study applied life cycle assessment (LCA) and project economics to estimate and compare the land intensity and profitability of anaerobic digestion and wind energy projects in the Great Plains. The results show that significantly more energy and revenue can be generated per hectare of land using wind versus anaerobic digestion. Economically, the benefit-to-cost ratios of wind farms were almost twice as favorable as anaerobic digester facilities. Wind farms have consistent benefit-to-cost ratios of 2.15 while the anaerobic digester facilities benefit to cost ratios range from 1.2 to 1.25. Legislature changes to RPS could incentivize increasing the number of anaerobic digesters while also assisting in reversing the current trend of diminishing dairy farms while reducing climate change risks and creating new economic opportunities for renewable energy. - Highlights: • Wind 1160 GW h to 28,706 GW h between 2 and 129 ha. • AD 29 GW h to 393 GW h between 14 and 105 ha. • More energy and revenue can be generated per hectare using wind energy AD. • An ideal solution for dairy farmers may be an integrated solution • State legislature changes to RPS could incentivize increasing AD facilities.

What Aspects of Rural Life Contribute to Rural-Urban Health Disparities in Older Adults? Evidence From a National Survey.

Science.gov (United States)

Cohen, Steven A; Cook, Sarah K; Sando, Trisha A; Sabik, Natalie J

2017-11-29

Rural-urban health disparities are well-documented and particularly problematic for older adults. However, determining which specific aspects of rural or urban living initiate these disparities remains unclear. The purpose of this study was to assess associations between place-based characteristics of rural-urban status and health among adults age 65+. Data from the 2012 Behavioral Risk Factor Surveillance System were geographically linked to place-based characteristics from the American Community Survey. Self-reported health (SRH), obesity, and health checkup within the last year were modeled against rural-urban status (distance to nearest metropolitan area, population size, population density, percent urban, Urban Influence Codes [UIC], Rural-Urban Continuum Codes [RUCC], and Rural-Urban Commuting Area [RUCA]) using generalized linear models, accounting for covariates and complex sampling, overall, and stratified by area-level income. In general, increasing urbanicity was associated with a reduction in negative SRH for all 7 measures of rural-urban status. For low-income counties, this association held for all measures and characteristics of rural-urban status except population density. However, for high-income counties, the association was reversed-respondents living in areas of increasing urbanicity were more likely to report negative SRH for 4 of the 7 measures (RUCC, UIC, RUCA, and percent urban). Findings were mixed for the outcome of obesity, where rural areas had higher levels, except in low-income counties, where the association between rurality and obesity was reversed (OR 1.033, 95%CI: 1.002-1.064). These results suggest that rural-urban status is both a continuum and multidimensional. Distinct elements of rural-urban status may influence health in nuanced ways that require additional exploration in future studies. © 2017 National Rural Health Association.

Status of Technical and Vocational Education in Rural Institutions in ...

African Journals Online (AJOL)

This study was aimed at assessing the state of technical and vocational education in rural institutions in Delta State. Three research questions guided the study. A sample size of fifty (50) principals from 50 rural institutions in Delta State was used for the study. Data were collected using a questionnaire. The study reveals that ...

Population dynamics and rural poverty.

Science.gov (United States)

Fong, M S

1985-01-01

An overview of the relationship between demographic factors and rural poverty in developing countries is presented. The author examines both the micro- and macro-level perspectives of this relationship and the determinants and consequences of population growth. The author notes the prospects for a rapid increase in the rural labor force and considers its implications for the agricultural production structure and the need for institutional change. Consideration is also given to the continuing demand for high fertility at the family level and the role of infant and child mortality in the poverty cycle. "The paper concludes by drawing attention to the need for developing the mechanism for reconciliation of social and individual optima with respect to family size and population growth." The need for rural development projects that take demographic factors into account is stressed as is the need for effective population programs. (summary in FRE, ITA) excerpt

Characteristics of Ambient Black Carbon Mass and Size-Resolved Particle Number Concentrations during Corn Straw Open-Field Burning Episode Observations at a Rural Site in Southern Taiwan.

Science.gov (United States)

Cheng, Yu-Hsiang; Yang, Li-Sing

2016-07-08

Information on the effect of open-field burning of agricultural residues on ambient black carbon (BC) mass and size-resolved particle number concentrations is scarce. In this study, to understand the effect of such open-field burning on short-term air quality, real-time variations of the BC mass and size-resolved particle number concentrations were monitored before and during a corn straw open-field burning episode at a rural site. Correlations between the BC mass and size-resolved particle number concentrations during the episode were investigated. Moreover, the particle number size distribution and absorption Ångström exponent were determined for obtaining the characteristics of aerosol emissions from the corn straw open-field burning. The results can be used to address public health concerns and as a reference for managing similar episodes of open-field burning of agricultural residues.

Livestock Anaerobic Digester Database

Science.gov (United States)

The Anaerobic Digester Database provides basic information about anaerobic digesters on livestock farms in the United States, organized in Excel spreadsheets. It includes projects that are under construction, operating, or shut down.

Gas production analysis of a fixed-dome digester operated under temperate climates in central Ohio

Energy Technology Data Exchange (ETDEWEB)

Castano, J.; Martin, J.F.; Ciotola, R.; Schlea, D.; Eger, C. [Ohio State Univ., Columbus, OH (United States). Ecological Engineering Program

2010-07-01

Anaerobic digestion is not used in small farms in the United States because of the high costs and large size of existing digesters. More affordable digesters are needed to realize the environmental and energetic benefits on smaller farms in temperate climates. Field and laboratory experiments were conducted to determine the effects of seasonal temperature variation on gas production. Once a baseline for gas production and digester function is determined, then methods can be identified to increase gas production in these conditions. A 1 cubic metre modified fixed-dome digester was buried just below the soil surface at the Ohio State University dairy farm. The digester was fed with 1 kg/m{sup 3} per day of diluted cow manure. The kinetics associated with 6 specific anaerobic trophic groups at 5 and 15 degrees C were determined through laboratory experiments. The average ambient temperature from October through December 2009 was 7.2 degrees C, while the average digester temperature was 8.6 degrees C. The average specific gas production during this period was 0.01746 litres/Kg of volatile solids (VS). Preliminary results showed an average reduction of 44 per cent in VS and volatile fatty acids concentration of 8441 mg/litre inside the digester, from which 61 per cent, 26 per cent, 1 per cent, 7 per cent, and 5 per cent were acetic, propionic, isobutyric, isovaleric and valeric acids, respectively. These preliminary results suggest that the decreasing gas production is associated with a kinetic constraint for a specific trophic group.

In vivo digestion of bovine milk fat globules: effect of processing and interfacial structural changes. II. Upper digestive tract digestion.

Science.gov (United States)

Gallier, Sophie; Zhu, Xiang Q; Rutherfurd, Shane M; Ye, Aiqian; Moughan, Paul J; Singh, Harjinder

2013-12-01

The aim of this research was to study the effect of milk processing on the in vivo upper digestive tract digestion of milk fat globules. Fasted rats were serially gavaged over a 5h period with cream from raw, pasteurised, or pasteurised and homogenised milk. Only a few intact dietary proteins and peptides were present in the small intestinal digesta. Significantly (Praw (448 mg g(-1) digesta dry matter (DDM)) and homogenised creams (528 mg g(-1) DDM), as compared to pasteurised and homogenised cream (249 mg g(-1) DDM). Microscopy techniques were used to investigate the structural changes during digestion. Liquid-crystalline lamellar phases surrounding the fat globules, fatty acid soap crystals and lipid-mucin interactions were evident in all small intestinal digesta. Overall, the pasteurised and homogenised cream appeared to be digested to a greater extent. Copyright © 2013 Elsevier Ltd. All rights reserved.

Co-digestion to support low temperature anaerobic pretreatment of municipal sewage in a UASB–digester

NARCIS (Netherlands)

Lei Zhang,; Hendrickx, T.L.G.; Kampman, C.; Temmink, B.G.; Zeeman, G.

2013-01-01

The aim of this work was to demonstrate that co-digestion improves soluble sewage COD removal efficiency in treatment of low temperature municipal sewage by a UASB–digester system. A pilot scale UASB–digester system was applied to treat real municipal sewage, and glucose was chosen as a model

Optimization of solid state anaerobic digestion of the OFMSW by digestate recirculation: A new approach

International Nuclear Information System (INIS)

Michele, Pognani; Giuliana, D’Imporzano; Carlo, Minetti; Sergio, Scotti; Fabrizio, Adani

2015-01-01

Highlights: • Solid State Anaerobic Digestion (SSAD) of OFMSW can be optimized by irrigation with digestate. • Digestate spreading allows keeping optimal process parameters and high hydrolysis rate. • The 18.4% of CH 4 was produced in the reactor, leaving the 49.7% in the percolate. • Successive CSTR feed with percolate shows a biogas enriched in methane (more than 80%). • The proposed process allow producing the 68% of OFMSW potential CH 4 , getting high quality organic amendment. - Abstract: Dry anaerobic digestion (AD) of OFMSW was optimized in order to produce biogas avoiding the use of solid inoculum. Doing so the dry AD was performed irrigating the solid waste with liquid digestate (flow rate of 1:1.18–1:0.9 w/w waste/digestate; 21 d of hydraulic retention time – HRT) in order to remove fermentation products inhibiting AD process. Results indicated that a high hydrolysis rate of organic matter (OM) and partial biogas production were obtained directly during the dry AD. Hydrolysate OM was removed from digester by the percolate flow and it was subsequently used to feed a liquid anaerobic digester. During dry AD a total loss of 36.9% of total solids was recorded. Methane balance indicated that 18.4% of potential methane can be produced during dry AD and 49.7% by the percolate. Nevertheless results obtained for liquid AD digestion indicated that only 20.4% and 25.7% of potential producible methane was generated by adopting 15 and 20 days of HRT, probably due to the AD inhibition due to high presence of toxic ammonia forms in the liquid medium

Optimization of solid state anaerobic digestion of the OFMSW by digestate recirculation: A new approach

Energy Technology Data Exchange (ETDEWEB)

Michele, Pognani, E-mail: michele.pognani@unimi.it [Gruppo Ricicla – DiSAA, Università degli Studi di Milano, Soil and Env. Lab, Via Celoria, 2, 20133 Milano (Italy); Giuliana, D’Imporzano, E-mail: giuliana.dimporzano@unimi.it [Gruppo Ricicla – DiSAA, Università degli Studi di Milano, Soil and Env. Lab, Via Celoria, 2, 20133 Milano (Italy); Gruppo Ricicla - DiSAA, Università degli Studi di Milano, Biomass and Bioenergy Lab., Parco Tecnologico Padano, Via Einstein, Loc. C.na Codazza, 26900 Lodi (Italy); Carlo, Minetti, E-mail: carlo.minetti@a2a.eu [Ecodeco, a2a Group, Cascina Darsena 1, 27010 Giussago, Pavia (Italy); Sergio, Scotti, E-mail: sergio.scotti@a2a.eu [Ecodeco, a2a Group, Cascina Darsena 1, 27010 Giussago, Pavia (Italy); Fabrizio, Adani, E-mail: farbrizio.adani@unimi.it [Gruppo Ricicla – DiSAA, Università degli Studi di Milano, Soil and Env. Lab, Via Celoria, 2, 20133 Milano (Italy); Gruppo Ricicla - DiSAA, Università degli Studi di Milano, Biomass and Bioenergy Lab., Parco Tecnologico Padano, Via Einstein, Loc. C.na Codazza, 26900 Lodi (Italy)

2015-01-15

Highlights: • Solid State Anaerobic Digestion (SSAD) of OFMSW can be optimized by irrigation with digestate. • Digestate spreading allows keeping optimal process parameters and high hydrolysis rate. • The 18.4% of CH{sub 4} was produced in the reactor, leaving the 49.7% in the percolate. • Successive CSTR feed with percolate shows a biogas enriched in methane (more than 80%). • The proposed process allow producing the 68% of OFMSW potential CH{sub 4}, getting high quality organic amendment. - Abstract: Dry anaerobic digestion (AD) of OFMSW was optimized in order to produce biogas avoiding the use of solid inoculum. Doing so the dry AD was performed irrigating the solid waste with liquid digestate (flow rate of 1:1.18–1:0.9 w/w waste/digestate; 21 d of hydraulic retention time – HRT) in order to remove fermentation products inhibiting AD process. Results indicated that a high hydrolysis rate of organic matter (OM) and partial biogas production were obtained directly during the dry AD. Hydrolysate OM was removed from digester by the percolate flow and it was subsequently used to feed a liquid anaerobic digester. During dry AD a total loss of 36.9% of total solids was recorded. Methane balance indicated that 18.4% of potential methane can be produced during dry AD and 49.7% by the percolate. Nevertheless results obtained for liquid AD digestion indicated that only 20.4% and 25.7% of potential producible methane was generated by adopting 15 and 20 days of HRT, probably due to the AD inhibition due to high presence of toxic ammonia forms in the liquid medium.

Parasitic infections of digestive tract of dogs in territory of Braničevo District

Directory of Open Access Journals (Sweden)

Đurić Boban

2011-01-01

Full Text Available This paper presents the results of two-year investigations of parasitic infections of the digestive tract of dogs originating from the territories of eight municipalities of Braničevo District. Investigations were performed on 345 dogs of different breeds and age categories, originating from rural and urban environments. The investigations encompassed dogs bred in decent hygiene conditions, as well as dogs living in unhygienic conditions. Some of the dogs covered by these analyses were dewormed, but the bulk of the sampled material originated from dogs that were not treated with antihelminthics. Eight species of parasites of the digestive tract were diagnosed in the examined dogs from the territory of the Braničevo District: Toxocara canis, Ancylostoma caninum, Uncinaria stenocephala, Trichuris vulpis, coccidiae, Dipylidium caninum, Taenia spp. and Alaria alata. Today, it is still necessary to keep dogs in rural environments and isolated areas, since these animals are used to guard real estate and cattle. For quite some time now, there has also been wide-spread interest in keeping dogs in urban areas as well. It is evident on the grounds of data from big towns that the number of dogs in urban environments has been increasing constantly all over the world. However, the conditions for naturally maintaining dogs in towns have become increasingly more difficult and complicated. The amount of free space and the number of yards are constantly being reduced, so that dog owners are compelled to keep their pets in apartments. These altered living and diet conditions have resulted in more complex and varied health problems of dogs.

Digestion of chrysanthemum stunt viroid by leaf extracts of Capsicum chinense indicates strong RNA-digesting activity.

Science.gov (United States)

Iraklis, Boubourakas; Kanda, Hiroko; Nabeshima, Tomoyuki; Onda, Mayu; Ota, Nao; Koeda, Sota; Hosokawa, Munetaka

2016-08-01

CSVd could not infect Nicotiana benthamiana when the plants were pretreated with crude leaf extract of Capsicum chinense 'Sy-2'. C. chinense leaves were revealed to contain strong RNA-digesting activity. Several studies have identified active antiviral and antiviroid agents in plants. Capsicum plants are known to contain antiviral agents, but the mechanism of their activity has not been determined. We aimed to elucidate the mechanism of Capsicum extract's antiviroid activity. Chrysanthemum stunt viroid (CSVd) was inoculated into Nicotiana benthamiana plants before or after treating the plants with a leaf extract of Capsicum chinense 'Sy-2'. CSVd infection was determined using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) 3 weeks after inoculation. When Capsicum extract was sprayed or painted onto N. benthamiana before inoculation, it was effective in preventing infection by CSVd. To evaluate CSVd digestion activity in leaf extracts, CSVd was mixed with leaf extracts of Mirabilis, Phytolacca, Pelargonium and Capsicum. CSVd-digesting activities were examined by quantifying undigested CSVd using qRT-PCR, and RNA gel blotting permitted visualization of the digested CSVd. Only Capsicum leaf extract digested CSVd, and in the Capsicum treatment, small digested CSVd products were detected by RNA gel blot analysis. When the digesting experiment was performed for various cultivars and species of Capsicum, only cultivars of C. chinense showed strong CSVd-digesting activity. Our observations indicated that Capsicum extract contains strong RNA-digesting activity, leading to the conclusion that this activity is the main mechanism for protection from infection by CSVd through spraying or painting before inoculation. To our knowledge, this is the first report of a strong RNA-digesting activity by a plant extract.

Analysis of digester design concepts

Energy Technology Data Exchange (ETDEWEB)

Ashare, E.; Wilson, E. H.

1979-01-29

Engineering economic analyses were performed on various digester design concepts to determine the relative performance for various biomass feedstocks. A comprehensive literature survey describing the state-of-the-art of the various digestion designs is included. The digester designs included in the analyses are CSTR, plug flow, batch, CSTR in series, multi-stage digestion and biomethanation. Other process options investigated included pretreatment processes such as shredding, degritting, and chemical pretreatment, and post-digestion processes, such as dewatering and gas purification. The biomass sources considered include feedlot manure, rice straw, and bagasse. The results of the analysis indicate that the most economical (on a unit gas cost basis) digester design concept is the plug flow reactor. This conclusion results from this system providing a high gas production rate combined with a low capital hole-in-the-ground digester design concept. The costs determined in this analysis do not include any credits or penalties for feedstock or by-products, but present the costs only for conversion of biomass to methane. The batch land-fill type digester design was shown to have a unit gas cost comparable to that for a conventional stirred tank digester, with the potential of reducing the cost if a land-fill site were available for a lower cost per unit volume. The use of chemical pretreatment resulted in a higher unit gas cost, primarily due to the cost of pretreatment chemical. A sensitivity analysis indicated that the use of chemical pretreatment could improve the economics provided a process could be developed which utilized either less pretreatment chemical or a less costly chemical. The use of other process options resulted in higher unit gas costs. These options should only be used when necessary for proper process performance, or to result in production of a valuable by-product.

Economic growth, poverty and rural labour markets in India: a survey of research.

OpenAIRE

Bardhan K

1983-01-01

ILO pub-WEP pub. Working paper on the relationship between agricultural development, agrarian structures, rural employment and poverty in India - based on a literature survey, examines trends in rural population, agricultural income, labour contracts, farm size and food prices; investigates the role of agricultural credit, wage determination and labour market segmentation; considers the informal sector and rural public works. Bibliography.

Food waste co-digestion with slaughterhouse waste and sewage sludge: Digestate conditioning and supernatant quality.

Science.gov (United States)

Borowski, Sebastian; Boniecki, Paweł; Kubacki, Przemysław; Czyżowska, Agata

2018-04-01

In this study, the anaerobic mesophilic co-digestion of food waste (FW) with municipal sewage sludge (MSS) and slaughterhouse waste (SHW) was undertaken in 3-dm 3 laboratory reactors as well as in 50-dm 3 reactors operated in semi-continuous conditions. The highest methane yield of around 0.63 m 3 CH 4 /kgVS fed was achieved for the mixture of FW and SHW treated in the laboratory digester operated at solids retention time (SRT) of 30 days, whereas the co-digestion of FW with MSS under similar operating conditions produced 0.46 m 3 of methane from 1 kgVS fed . No significant differences between methane yields from laboratory digesters and large-scale reactors were reported. The conditioning tests with the digestates from reactor experiments revealed the highest efficiency of inorganic coagulants among all investigated chemicals, which applied in a dose of 10 g/kg allowed to reduce capiliary suction time (CST) of the digestate below 20 s. The combined conditioning with coagulants and bentonite did not further reduce the CST value but improved the quality of the digestate supernatant. In particular, the concentrations of suspended solids, COD as well as metals in the supernatant were considerably lowered. Copyright © 2017. Published by Elsevier Ltd.

Digesters and demographics: identifying support for anaerobic digesters on dairy farms.

Science.gov (United States)

Sanders, D J; Roberts, M C; Ernst, S C; Thraen, C S

2010-11-01

The dairy industry in the United States is amidst a long-running trend toward fewer, larger dairy farms. This development has created a backlash in some communities over concerns such as odor, waste management, and environmental degradation. Separately, anaerobic digestion has advanced as a waste management technology that potentially offers solutions to some of these issues, providing odor control and a combustible biogas among other things. These digesters require significant capital investments. Voluntary consumer premiums for the renewable energy produced have been used in some instances as a means to move adoption of such systems toward financial feasibility. This project employed a survey to measure Ohio consumers' willingness to pay a premium for renewable energy produced by anaerobic digesters on dairy farms. Cluster analysis was used to segment consumers by willingness to pay, age, education, income, self-identified political inclination, and a composite variable that served as a proxy for respondents' environmental stewardship. Four distinctive groups emerged from the data. Older, less educated respondents were found to have the least amount of support for digesters on dairy farms, whereas politically liberal, environmentally proactive respondents demonstrated the strongest support. Well-educated, affluent respondents and young respondents fell between these 2 groups. Most large dairy farms are generally met with fairly negative responses from their local communities; in contrast, this research finds some popular support for anaerobic digestion technology. Going forward, establishing a positive link between support for anaerobic digesters and for their use on large dairies could open up a new route for less-contested large dairy farm developments. Evaluation of community demographics could become an important part of finding an optimal location for a large dairy farm. Copyright © 2010 American Dairy Science Association. Published by Elsevier Inc. All

A kinetic model to simulate the effect of cooking time-temperature on the gastric digestion of meat

OpenAIRE

Kondjoyan, Alain; Daudin, Jean-Dominique; Portanguen, Stéphane; Aubry, Laurent; Sante-Lhoutellier, Veronique

2014-01-01

A kinetic model was developed to predict the effect of cooking time and temperature on the digestibility of myofibrillar proteins. The predictions were confronted to the measurement of the in vitro digestibility of myofibrillar proteins coming from either slices of beef meat heated in water bath or from a piece of meat roasted in a domestic oven. The model was able to simulate the in vitro measurements for the meat pieces of different sizes cooked under different condi...

Impact of food processing on rye product properties and their in vitro digestion.

Science.gov (United States)

Johansson, Daniel P; Gutiérrez, José L Vázquez; Landberg, Rikard; Alminger, Marie; Langton, Maud

2018-06-01

Rye products have been reported to elicit postprandial insulin and glucose responses which may be beneficial for prevention of type-2 diabetes. However, mechanisms underlying variations in responses related to processing techniques are not fully understood. Five differently processed rye products (sourdough-fermented bread, fermented and unfermented crispbread, extrusion-cooked rye, and porridge) and refined wheat bread were characterised. Two in vitro methods, a dynamic method simulating digestion in the stomach and small intestine and a static method, simulating conditions in the stomach were used to determine viscosity development, structural changes and release of glucose during digestion. Structural and compositional differences induced by processing influenced product digestion. Gastric disintegration and digesta particle size were related to characteristics of the starch/protein matrix, while digesta viscosity was reduced due to fibre degradation during fermentation. More cohesive boluses were associated with slower glucose release. Sourdough fermentation increased amylose leakage and appeared to inhibit starch hydrolysis despite low digesta viscosity and rapid disintegration. The net release of glucose during digestion of foods is determined by several factors which may vary in their importance depending on product specific properties.

'Poorly defined': unknown unknowns in New Zealand Rural Health.

Science.gov (United States)

Fearnley, David; Lawrenson, Ross; Nixon, Garry

2016-08-05

There is a considerable mismatch between the population that accesses rural healthcare in New Zealand and the population defined as 'rural' using the current statistics New Zealand rural and urban categorisations. Statistics New Zealand definitions (based on population size or density) do not accurately identify the population of New Zealanders who actually access rural health services. In fact, around 40% of people who access rural health services are classified as 'urban' under the Statistics New Zealand definition, while a further 20% of people who are currently classified as 'rural' actually have ready access to urban health services. Although there is some recognition that current definitions are suboptimal, the extent of the uncertainty arising from these definitions is not widely appreciated. This mismatch is sufficient to potentially undermine the validity of both nationally-collated statistics and also any research undertaken using Statistics New Zealand data. Under these circumstances it is not surprising that the differences between rural and urban health care found in other countries with similar health services have been difficult to demonstrate in New Zealand. This article explains the extent of this mismatch and suggests how definitions of rural might be improved to allow a better understanding of New Zealand rural health.

Monitoring the aeration efficiency and carbon footprint of a medium-sized WWTP: experimental results on oxidation tank and aerobic digester.

Science.gov (United States)

Caivano, Marianna; Bellandi, Giacomo; Mancini, Ignazio M; Masi, Salvatore; Brienza, Rosanna; Panariello, Simona; Gori, Riccardo; Caniani, Donatella

2017-03-01

The efficiency of aeration systems should be monitored to guarantee suitable biological processes. Among the available tools for evaluating the aeration efficiency, the off-gas method is one of the most useful. Increasing interest towards reducing greenhouse gas (GHG) emissions from biological processes has resulted in researchers using this method to quantify N 2 O and CO 2 concentrations in the off-gas. Experimental measurements of direct GHG emissions from aerobic digesters (AeDs) are not available in literature yet. In this study, the floating hood technique was used for the first time to monitor AeDs. The floating hood technique was used to evaluate oxygen transfer rates in an activated sludge (AS) tank of a medium-sized municipal wastewater treatment plant located in Italy. Very low values of oxygen transfer efficiency were found, confirming that small-to-medium-sized plants are often scarcely monitored and wrongly managed. Average CO 2 and N 2 O emissions from the AS tank were 0.14 kg CO2 /kg bCOD and 0.007 kg CO2,eq /kg bCOD , respectively. For an AeD, 3 × 10 -10  kg CO2 /kg bCOD direct CO 2 emissions were measured, while CO 2,eq emissions from N 2 O were 4 × 10 -9  kg CO2,eq /kg bCOD . The results for the AS tank and the AeD were used to estimate the net carbon and energy footprint of the entire plant.

Bio-synthesis and antimicrobial activity of silver nanoparticles using anaerobically digested parthenium slurry.

Science.gov (United States)

Adur, Alaknanda J; Nandini, N; Shilpashree Mayachar, K; Ramya, R; Srinatha, N

2018-06-01

Silver nanoparticles were prepared through eco-friendly, cost effective, bio-mediated technique using anaerobically digested Parthenium hysterophorous digested slurry (PDS) for the first time. The synthesized nanoparticles were characterized through different techniques such as UV-Vis spectrophotometer for optical properties; X-ray diffractometer (XRD), high resolution transmission electron spectroscopy (HR-TEM) and Fourier Transform Infra Red (FTIR) Spectroscopy for structural property investigations. It was observed that the prepared silver nanoparticles were crystallized in face centered cubic crystal structure with an average particle size of 19 nm as confirmed from XRD. Also HR-TEM studies reveal the formation of nano-sized silver particles with face centered cubic nano structure. In addition, absorption spectra exhibit Surface Plasmon Resonance (SPR) which suggests the formation of silver nanoparticles. FTIR results show the presence of different characteristic functional groups and their stretching / bending vibrations in turn responsible for the bioreduction of silver ions in Parthenium digested slurry. Further investigations on antimicrobial activity were done by subjecting the synthesized silver nanoparticles on E-coli and Pseudomonas as marker organisms for the group of gram negative bacteria by well plate method on enrichment media. The result obtained shows a clear zone of inhibition confirming the antibacterial activity. Overall, the investigated results confirm the biosynthesized silver nanoparticles are potential candidates for antimicrobial activity applications. Copyright © 2018 Elsevier B.V. All rights reserved.

Do digestive contents confound body mass as a measure of relative condition in nestling songbirds?

Science.gov (United States)

Streby, Henry M.; Peterson, Sean M.; Lehman, Justin A.; Kramer, Gunnar R.; Vernasco, Ben J.; Andersen, David E.

2014-01-01

Relative nestling condition, typically measured as nestling mass or as an index including nestling mass, is commonly purported to correlate with fledgling songbird survival. However, most studies directly investigating fledgling survival have found no such relationship. We weighed feces and stomach contents of nestling golden-winged warblers (Vermivora chrysoptera) to investigate the potential contribution of variation in digestive contents to differences in nestling mass. We estimated that the mass of a seventh-day (near fledging) nestling golden-winged warbler varies by 0.65 g (approx. 9% of mean nestling mass) depending on the contents of the nestling's digestive system at the time of weighing, and that digestive contents are dissimilar among nestlings at any moment the brood is removed from the nest for weighing. Our conservative estimate of within-individual variation in digestive contents equals 72% and 24% of the mean within-brood and population-wide range in nestling mass, respectively. Based on our results, a substantive but typically unknown amount of the variation in body mass among nestlings is confounded by differences in digestive contents. We conclude that short-term variation in digestive contents likely precludes the use of body mass, and therefore any mass-dependent index, as a measure of relative nestling condition or as a predictor of survival in golden-winged warblers and likely in many other songbirds of similar size.

Lysosomal responses in the digestive gland of the freshwater mussel, Dreissena polymorpha, experimentally exposed to cadmium

International Nuclear Information System (INIS)

Giamberini, Laure; Cajaraville, Miren P.

2005-01-01

In order to examine the possible use of lysosomal response as a biomarker of freshwater quality, structural changes of lysosomes were measured by image analysis in the digestive gland of the zebra mussel, Dreissena polymorpha, exposed in laboratory conditions to cadmium. Mussels were exposed to the metal (10 and 200 μg/L) for 3 weeks and randomly collected after 7 and 21 days. At each treatment day, digestive tissues were excised and β-glucuronidase activity was revealed in cryotome sections. Four stereological parameters were calculated: lysosomal volume density, lysosomal surface density, lysosomal surface to volume ratio, and lysosomal numerical density. The changes observed in this study reflected a general activation of the lysosomal system, including an increase in both the number and the size of lysosomes in the digestive gland cells of mussels exposed to cadmium. The digestive lysosomal response in zebra mussels was related to exposure time and to metal concentration, demonstrating the potential of this biomarker in freshwater biomonitoring

Digestibility marker and ileal amino acid digestibility in phytase-supplemented soybean or canola meals for growing pigs.

Science.gov (United States)

Favero, A; Ragland, D; Vieira, S L; Owusu-Asiedu, A; Adeola, O

2014-12-01

Two experiments using soybean meal (SBM) or canola meal (CM) were conducted to investigate whether the choice of digestibility marker influenced the apparent ileal digestibility (AID) or standardized ileal digestibility (SID) of N and AA in diets supplemented with phytase. In each experiment, 18 barrows fitted with T-cannulas at the ileocecal junction were assigned to 3 diets consisting of a N-free diet to determine endogenous losses of N and AA, a semipurified diet (SBM in Exp. 1 or CM in Exp. 2), and the semipurified diet supplemented with phytase at 1,000 phytase units/kg. Three digestibility markers including acid-insoluble ash (AIA), chromic oxide (Cr2O3), and titanium dioxide (TiO2) were added to each diet at 3 g/kg. Each diet was fed for 7 d, consisting of a 5-d adjustment and a 2-d collection of ileal digesta. In both studies, basal ileal endogenous losses determined with Cr2O3 as a digestibility marker were lower (Pdigestibility markers. Using SBM as the protein source in Exp. 1, there was no interaction between phytase and digestibility marker on AID or SID of AA. The AID of N and AA in SBM using AIA as a digestibility marker tended to be lower (Pdigestibility markers. Phytase supplementation increased (Pdigestibility marker tended to be associated with lower (Pdigestibility marker and phytase. Phytase supplementation had effects (Pdigestibility marker. With Cr2O3 or TiO2 as the digestibility marker in the CM diets, phytase supplementation increased (Pdigestibility marker. In contrast, there were no clear improvements in AA digestibility from phytase supplementation for SBM. Phytase effects on AID or SID of AA were dependent on the digestibility marker used in diets when CM was used as the protein source but not when SBM was used as the protein source. Therefore, AA digestibility response to phytase supplementation may depend on the protein being evaluated as well as the choice of digestibility marker.

Anaerobic digestion of onion residuals using a mesophilic Anaerobic Phased Solids Digester

International Nuclear Information System (INIS)

Romano, Rowena T.; Zhang, Ruihong

2011-01-01

The anaerobic digestion of onion residual from an onion processing plant was studied under batch-fed and continuously-fed mesophilic (35 ± 2 o C) conditions in an Anaerobic Phased Solids (APS) Digester. The batch digestion tests were performed at an initial loading of 2.8 gVS L -1 and retention time of 14 days. The biogas and methane yields, and volatile solids reduction from the onion residual were determined to be 0.69 ± 0.06 L gVS -1 , 0.38 ± 0.05 L CH 4 gVS -1 , and 64 ± 17%, respectively. Continuous digestion tests were carried out at organic loading rates (OLRs) of 0.5-2.0 gVS L -1 d -1 . Hydrated lime (Ca(OH) 2 ) was added to the APS-Digester along with the onion residual at 16 mg Ca(OH) 2 gVS -1 to control the pH of the biogasification reactor above 7.0. At steady state the average biogas yields were 0.51, 0.56, and 0.62 L gVS -1 for the OLRs of 0.5, 1.0, and 2.0 gVS L -1 d -1 respectively. The methane yields at steady state were 0.29, 0.32, and 0.31 L CH 4 gVS -1 for the OLRs of 0.5, 1.0, and 2.0 gVS L -1 d -1 respectively. The study shows that the digestion of onion residual required proper alkalinity and pH control, which was possible through the use of caustic chemicals. However, such chemicals will begin to have an inhibitory effect on the microbial population at high loading rates, and therefore alternative operational parameters are needed. -- Highlights: → An APS-Digester was used to study biogas production from onion solid residues. → Biogas and methane yields from onion solids were determined. → Study showed substantial findings for treating onion solid residues.

Anaerobic digestion for sustainable development: a natural approach.

Science.gov (United States)

Gljzen, H J

2002-01-01

After the discovery of methane gas by Alessandro Volta in 1776, it took about 100 years before anaerobic processes for the treatment of wastewater and sludges were introduced. The development of high rate anaerobic digesters for the treatment of sewage and industrial wastewater took until the nineteen-seventies and for solid waste even till the nineteen-eighties. All digesters have in common that they apply natural anaerobic consortia of microorganisms for degradation and transformation processes. In view of this, it could be rewarding to evaluate the efficiency of natural ecosystems for their possible application. Examples of high rate anaerobic natural systems include the forestomach of ruminants and the hindgut of certain insects, such as termites and cockroaches. These 'natural reactors' exhibit volumetric methane production rates as high as 35 l/l.d. The development of anaerobic reactors based on such natural anaerobic systems could produce eco-technologies for the effective management of a wide variety of solid wastes and industrial wastewater. Important limitations of anaerobic treatment of domestic sewage relate to the absence of nutrient and pathogen removal. A combination of anaerobic pre-treatment followed by photosynthetic posttreatment is proposed for the effective recovery of energy and nutrients from sewage. This eco-technology approach is based on the recognition that the main nutrient assimilating capacity is housed in photosynthetic plants. The proposed anaerobic-photosynthetic process is energy efficient, cost effective and applicable under a wide variety of rural and urban conditions. a natural systems approach towards waste management could generate affordable eco-technologies for effective treatment and resource recovery.

In vitro starch digestion correlates well with rate and extent of starch digestion in broiler chickens

NARCIS (Netherlands)

Weurding, R.E.; Veldman, R.; Veen, W.A.G.; Aar, van der P.J.; Verstegen, M.W.A.

2001-01-01

Current feed evaluation systems for poultry are based on digested components (fat, protein and nitrogen-free extracts). Digestible starch is the most important energy source in broiler chicken feeds and is part of the nitrogen-free extract fraction. Digestible starch may be predicted using an in

Usage and recall of FMCG brands by rural consumers and relevant facts

Directory of Open Access Journals (Sweden)

Savanam Chandra Sekhar

2015-01-01

Full Text Available India is a country of villages. It has mammoth rural population of 833 million spread over 640,867 villages. Rural markets are small in size, distantly scattered and heterogeneous. They provide awesome opportunities for fast moving consumer goods (FMCG companies. Rural consumers aspire to use brands rather than just commodities. At this juncture, understand rural consumer usage of FMCG brands and awareness is perceived appropriate. The objective of this research paper is to study the usage and recall of FMCG brands by rural consumers in Prakasam district of Andhra Pradesh in India. Thus, a modest attempt is made in this paper to divulge relevant facts of the topic with empirical data. This article is quite useful to the stakeholders of rural marketing.

Covering Materials for Anaerobic Digesters Producing Biogas

International Nuclear Information System (INIS)

Itodo, I. N.; Philips, T. K.

2002-01-01

The suitability of foam, concrete and clay soil as covering material on anaerobic digesters producing biogas was investigated using four batch-type digesters of 20 litres volume. The methane yield from the digesters was of the order: foam >control> concrete > clay soil. The digester covered with foam had the highest methane yield, best temperature control and most favourable pH conditions. It is most suitable as cover material on anaerobic digesters

Anaerobic digestion in mesophilic and room temperature conditions: Digestion performance and soil-borne pathogen survival.

Science.gov (United States)

Chen, Le; Jian, Shanshan; Bi, Jinhua; Li, Yunlong; Chang, Zhizhou; He, Jian; Ye, Xiaomei

2016-05-01

Tomato plant waste (TPW) was used as the feedstock of a batch anaerobic reactor to evaluate the effect of anaerobic digestion on Ralstonia solanacearum and Phytophthora capsici survival. Batch experiments were carried out for TS (total solid) concentrations of 2%, 4% and 6% respectively, at mesophilic (37±1°C) and room (20-25°C) temperatures. Results showed that higher digestion performance was achieved under mesophilic digestion temperature and lower TS concentration conditions. The biogas production ranged from 71 to 416L/kg VS (volatile solids). The inactivation of anaerobic digestion tended to increase as digestion performance improved. The maximum log copies reduction of R. solanacearum and P. capsici detected by quantitative PCR (polymerase chain reaction) were 3.80 and 4.08 respectively in reactors with 4% TS concentration at mesophilic temperatures. However, both in mesophilic and room temperature conditions, the lowest reduction of R. solanacearum was found in the reactors with 6% TS concentration, which possessed the highest VFA (volatile fatty acid) concentration. These findings indicated that simple accumulation of VFAs failed to restrain R. solanacearum effectively, although the VFAs were considered poisonous. P. capsici was nearly completely dead under all conditions. Based on the digestion performance and the pathogen survival rate, a model was established to evaluate the digestate biosafety. Copyright © 2015. Published by Elsevier B.V.

Development of the Digestive System-Experimental Challenges and Approaches of Infant Lipid Digestion.

Science.gov (United States)

Abrahamse, Evan; Minekus, Mans; van Aken, George A; van de Heijning, Bert; Knol, Jan; Bartke, Nana; Oozeer, Raish; van der Beek, Eline M; Ludwig, Thomas

2012-12-01

At least during the first 6 months after birth, the nutrition of infants should ideally consist of human milk which provides 40-60 % of energy from lipids. Beyond energy, human milk also delivers lipids with a specific functionality, such as essential fatty acids (FA), phospholipids, and cholesterol. Healthy development, especially of the nervous and digestive systems, depends fundamentally on these. Epidemiological data suggest that human milk provides unique health benefits during early infancy that extend to long-lasting benefits. Preclinical findings show that qualitative changes in dietary lipids, i.e., lipid structure and FA composition, during early life may contribute to the reported long-term effects. Little is known in this respect about the development of digestive function and the digestion and absorption of lipids by the newborn. This review gives a detailed overview of the distinct functionalities that dietary lipids from human milk and infant formula provide and the profound differences in the physiology and biochemistry of lipid digestion between infants and adults. Fundamental mechanisms of infant lipid digestion can, however, almost exclusively be elucidated in vitro. Experimental approaches and their challenges are reviewed in depth.

Digestive enzyme activities in the guts of bonnethead sharks (Sphyrna tiburo) provide insight into their digestive strategy and evidence for microbial digestion in their hindguts.

Science.gov (United States)

Jhaveri, Parth; Papastamatiou, Yannis P; German, Donovan P

2015-11-01

Few investigations have studied digestive enzyme activities in the alimentary tracts of sharks to gain insight into how these organisms digest their meals. In this study, we examined the activity levels of proteases, carbohydrases, and lipase in the pancreas, and along the anterior intestine, spiral intestine, and colon of the bonnethead shark, Sphyrna tiburo. We then interpreted our data in the context of a rate-yield continuum to discern this shark's digestive strategy. Our data show anticipated decreasing patterns in the activities of pancreatic enzymes moving posteriorly along the gut, but also show mid spiral intestine peaks in aminopeptidase and lipase activities, which support the spiral intestine as the main site of absorption in bonnetheads. Interestingly, we observed spikes in the activity levels of N-acetyl-β-D-glucosaminidase and β-glucosidase in the bonnethead colon, and these chitin- and cellulose-degrading enzymes, respectively, are likely of microbial origin in this distal gut region. Taken in the context of intake and relatively long transit times of food through the gut, the colonic spikes in N-acetyl-β-D-glucosaminidase and β-glucosidase activities suggest that bonnetheads take a yield-maximizing strategy to the digestive process, with some reliance on microbial digestion in their hindguts. This is one of the first studies to examine digestive enzyme activities along the gut of any shark, and importantly, the data match with previous observations that sharks take an extended time to digest their meals (consistent with a yield-maximizing digestive strategy) and that the spiral intestine is the primary site of absorption in sharks. Copyright © 2015 Elsevier Inc. All rights reserved.

Digestion of biogenic wastes from households, industry and wastes harvested on public grounds. Vergaerung biogener Abfaelle aus Haushalt, Industrie und Landschaftspflege; Schlussbericht: Band A

Energy Technology Data Exchange (ETDEWEB)

1991-01-01

The mass and biogas potentials of organic municipal and industrial solid wastes, as well as of wastes harvested on public grounds, have been determined. The mass potential was found to be around 285'000 tons of digestible organic matter per year. By digesting all this matter, theoretically, about 130'000'000 m[sup 3] of biogas or 3 PJ of energy could be generated yearly. The practical realizable potential is estimated to be nearly 2 PJ/a, including the savings by substituting the energy needed nowadays for the importation of peat and for the production of artificial fertilizers. Considering the fact, that the incineration of organic wastes costs more than biological treatment, the potential is relatively easy to realize. More than 50% of the humus losses of Swiss soils could be compensated by the application of digestion and composting technology. The different technologies for anaerobic digestion of solid organic wastes are compared: the thermophilic, one-stage digestion seems to be further advanced in development than (mesophilic) two-stage digestion. Co-digestion of sludges of municipal waste water treatment plants and solid organic wastes may be advantageous for rural areas. An appropriate marketing strategy for the application of the solid product, however, has to be looked at. Because the two-stage process seems to have some advantages regarding the rate of organic matter breakdown, the product quality and the hygienic conditions, a mesophilic two-stage experimental plant has been constructed. The results of the first experiment of a simple combination of a percolated hydrolytic step with a pulsating, dynamic anaerobic filter are presented. Data on the quality of the solid product from anaerobic digestion of biogenic solid wastes are given. (author) 9 figs., 11 tabs., 75 refs.

Spare capacity and phenotypic flexibility in the digestive system of a migratory bird: defining the limits of animal design.

Science.gov (United States)

McWilliams, Scott R; Karasov, William H

2014-05-22

Flexible phenotypes enable animals to live in environments that change over space and time, and knowing the limits to and the required time scale for this flexibility provides insights into constraints on energy and nutrient intake, diet diversity and niche width. We quantified the level of immediate and ultimate spare capacity, and thus the extent of phenotypic flexibility, in the digestive system of a migratory bird in response to increased energy demand, and identified the digestive constraints responsible for the limits on sustained energy intake. Immediate spare capacity decreased from approximately 50% for birds acclimated to relatively benign temperatures to less than 20% as birds approached their maximum sustainable energy intake. Ultimate spare capacity enabled an increase in feeding rate of approximately 126% as measured in birds acclimated for weeks at -29°C compared with +21°C. Increased gut size and not tissue-specific differences in nutrient uptake or changes in digestive efficiency or retention time were primarily responsible for this increase in capacity with energy demand, and this change required more than 1-2 days. Thus, the pace of change in digestive organ size may often constrain energy intake and, for birds, retard the pace of their migration.

Histological development of the digestive system of the Amazonian pimelodid catfish Pseudoplatystoma punctifer.

Science.gov (United States)

Gisbert, E; Moreira, C; Castro-Ruiz, D; Oztürk, S; Fernández, C; Gilles, S; Nuñez, J; Duponchelle, F; Tello, S; Renno, J F; García-Dávila, C; Darias, M J

2014-11-01

The organogenesis of the digestive system was described in the Amazonian pimelodid catfish species Pseudoplatystoma punctifer from hatching (3.5 mm total length, TL) to 41 days post-fertilization (dpf) (58.1 mm TL) reared at 28°C. Newly hatched larvae showed a simple digestive tract, which appeared as a straight undifferentiated and unfolded tube lined by a single layer of columnar epithelial cells (future enterocytes). During the endogenous feeding period, comprised between 20 and 96 h post-fertilization (3.5 to 6.1 mm TL), the larval digestive system experienced a fast transformation with the almost complete development and differentiation of most of digestive organs (buccopahrynx, oesophagus, intestine, liver and exocrine pancreas). Yolk reserves were not completely depleted at the onset of exogenous feeding (4 dpf, 6.1 mm TL), and a period of mixed nutrition was observed up to 6 to 7 dpf (6.8 to 7.3 mm TL) when yolk was definitively exhausted. The stomach was the organ that latest achieved its complete differentiation, characterized by the development of abundant gastric glands in the fundic stomach between 10 and 15 dpf (10.9 to 15.8 mm TL) and the formation of the pyloric sphincter at the junction of the pyloric stomach and the anterior intestine at 15 dpf (15.8 mm TL). The above-mentioned morphological and histological features observed suggested the achievement of a digestive system characteristic of P. punctifer juveniles and adults. The ontogeny of the digestive system in P. punctifer followed the same general pattern as in most Siluriform species so far, although some species-specific differences in the timing of differentiation of several digestive structures were noted, which might be related to different reproductive guilds, egg and larval size or even different larval rearing practices. According to present findings on the histological development of the digestive system in P. punctifer, some recommendations regarding the rearing practices of this

Risk assessment of metals in road-deposited sediment along an urban–rural gradient

International Nuclear Information System (INIS)

Zhao, Hongtao; Li, Xuyong

2013-01-01

We applied the traditional risk assessment methods originally designed for soils and river sediments to evaluation of risk associated with metals in road-deposited sediment (RDS) along an urban–rural gradient that included central urban (UCA), urban village (UVA), central suburban county (CSA), rural town (RTA), and rural village (RVA) areas in the Beijing metropolitan region. A new indicator RI RDS was developed which integrated the RDS characteristics of mobility, grain size and amount with the potential ecological risk index. The risk associated with metals in RDS in urban areas was generally higher than that in rural areas based on the assessment using traditional methods, but the risk was higher in urban and rural village areas than the areas with higher administration units based on the indicator RI RDS . These findings implied that RDS characteristics variation with the urban–rural gradient must be considered in metal risk assessment and RDS washoff pollution control. Highlights: ► Spatial pattern of metal risk level associated with road-deposited sediment (RDS) along urban–rural gradients varied. ► Risk level of metals changed significantly when grain size was considered. ► A new index integrating RDS characteristics and potential ecological risk was developed. ► Results from the new index were improved relative to those of traditional assessment methods. -- A new index integrating road-deposited sediment characteristics and potential ecological risk was developed to assess metal risk along the urban–rural gradient

The digestion of dietary triacylglycerols

DEFF Research Database (Denmark)

Mu, Huiling; Høy, Carl-Erik

2004-01-01

Dietary triacylglycerols (TAGs) are the major lipid components in the human diet and they are carriers of energy as well as important fatty acids. Many factors affect the digestion and absorption of TAGs. Evidence is accumulating that, in addition to the overall fatty acid profile, the TAG......, or one may speculate additionally on the possibilities of modifying the structure of fats to affect their absorption and the distribution of the fatty acids in the body after digestion and uptake. In this review we will summarize diverse aspects of TAG digestion and absorption, as well as the influences...... of the fatty acid composition and the intramolecular structure of dietary TAGs on their digestion and absorption....

Anaerobic digestion coupled with digestate injection reduced odour emissions from soil during manure distribution.

Science.gov (United States)

Orzi, V; Riva, C; Scaglia, B; D'Imporzano, G; Tambone, F; Adani, F

2018-04-15

This work aimed to measure the odour impact of untreated cow and pig slurries and treated (digestate and liquid fraction of digestate) manures when they were used on soil at a field scale, while also testing different spreading methods, i.e. surface vs. injection. Five experiments were performed in 2012-2016 on different farms. Odours were quantitatively (specific odour emission rate - SOER) (OU E m -2 h -1 ) measured by using dynamic olfactometry and qualitatively, i.e. to obtain an "odour fingerprint", by using an electronic nose (EN). Anaerobic digestion was effective in allowing the reduction of potential odour emission from digestates, so that when they were dosed on soil, odours emitted were much lower than those from soils on which untreated slurries were used. Slurries/digestate injection reduced much more odour emitted by soils so that SOER tended to become more similar to that of the control (untreated soil) although the odours were slightly greater. Odour fingerprint data indicated that there was a direct correlation between SOER and odour fingerprints. This was due to the ability of EN to detect ammonia, S-compounds and methane that were (the first two mainly), also, responsible for odours. Very good regression was found for Log SOER and EN by using a Partial Least Square (PLS) approach (R 2 =0.73; R 2 cv =0.66; Pfingerprints for control (Blank) and injected organic matrices were virtually identical, due to the creation of cavities in the soil during the injection that decreased the treated surface. Anaerobic digestion and subsequent digestate injection allowed us to reduce odour impact, avoiding annoyance to local inhabitants. Copyright © 2017 Elsevier B.V. All rights reserved.

What factors influence physiotherapy service provision in rural communities? A pilot study.

Science.gov (United States)

Adams, Robyn; Sheppard, Lorraine; Jones, Anne; Lefmann, Sophie

2014-06-01

To obtain stakeholder perspectives on factors influencing rural physiotherapy service provision and insights into decision making about service provision. Purposive sampling, open-ended survey questions and semi-structured interviews were used in this exploratory, qualitative study. A rural centre and its regional referral centre formed the pilot sites. Nine participant perspectives were obtained on rural physiotherapy services. Stakeholder perspectives on factors influencing rural physiotherapy service provision and service level decision making. Workforce capacity and capability, decision maker's knowledge of the role and scope of physiotherapy, consideration of physiotherapy within resource allocation decisions and proof of practice emerged as key issues. The latter three were particularly reflected in public sector participant comments. Business models and market size were identified factors in influencing private practice. Influencing factors described by participants both align and extend our understanding of issues described in the rural physiotherapy literature. Participant insights add depth and meaning to quantitative data by revealing impacts on local service provision. Available funding and facility priorities were key determinants of public sector physiotherapy service provision, with market size and business model appearing more influential in private practice. The level of self direction or choice about which services to provide, emerged as a point of difference between public and private providers. Decisions by public sector physiotherapists about service provision appear constrained by existing capacity and workload. Further research into service level decision making might provide valuable insights into rural health service delivery. © 2014 National Rural Health Alliance Inc.

Anaerobic Digestion. Student Manual. Biological Treatment Process Control.

Science.gov (United States)

Carnegie, John W., Ed.

This student manual contains the textual material for a four-lesson unit on anaerobic digestion control. Areas addressed include: (1) anaerobic sludge digestion (considering the nature of raw sludge, purposes of anaerobic digestion, the results of digestion, types of equipment, and other topics); (2) digester process control (considering feeding…

Participation and innovation, the keys to rural development: The case of rural Medellin

Directory of Open Access Journals (Sweden)

Rodríguez Adolfo Hernandez

2011-08-01

Full Text Available

size: 10pt; mso-fareast-font-family: MinionPro-Regular; mso-ansi-language: EN-US;" lang="EN-US">The challenge of rural development in the Municipality of Medellin has to do with a political decision to assess processes based on participation and innovation in rural communities. The authorities have the opportunity to establish a territory in order to guarantee stability and consolidation of the populations considering their many activities when the districts are threatened by rampant urban sprawl. The opportunity exists to rebuild civil society in the territory based on cultural identity and to build new spaces without exclusion.

Non-farm businesses local economic integration level: the case of six Portuguese small and medium-sized Markettowns - a sector approach

OpenAIRE

Diniz, Francisco

2004-01-01

Small and medium-sized towns in rural areas are of particular interest at this stage in the evolution of the European CAP. Serious consideration is being given to mechanisms that could transfer resources from the agricultural sector into a more diversified rural economy in order to safeguard the well-being of both the farming community and the wider rural population while still preserving the environmental assets which are such a valued feature of Europe's rural areas. Small and medium-sized ...

Ethnomedicinal plants used for digestive system disorders by the Karen of northern Thailand.

Science.gov (United States)

Tangjitman, Kornkanok; Wongsawad, Chalobol; Kamwong, Kaweesin; Sukkho, Treetip; Trisonthi, Chusie

2015-04-09

Digestive system disorders have a substantial effect on worldwide morbidity and mortality rates, including in Thailand, where the majority of the rural areas have a lack of proper sanitation and awareness about disease prevention. This has led to the prevalence of different types of digestive diseases. Karen people in Thailand still use medicinal plants as first aid remedies in treating these diseases. Therefore, this study aimed at documenting the plants used to cure and prevent different types of digestive system disorders by Karen people of Chiang Mai Province, northern Thailand. Ethnomedicinal data were collected from six key informants and 172 non-specialist informants regarding their traditional knowledge of medicinal plants. Quantitative approaches were used to determine Use Value (UV), Informant Consensus Factor (ICF) and Fidelity Level (FL) values. The study revealed that 36 medicinal plant species belonging to 31 genera and 24 families were used to treat digestive system disorders. The most prevalent plant families were Zingiberaceae (6 species), Euphorbiaceae (4 species) and Fabaceae (4 species). Leaves were the most commonly used plant part accounting for 32.6% of the plants, followed by the bark (18.6%). About 60% of the administrations were given orally by potion (60%) and consumption as food was also indicated (14%). The highest ICF values were recorded for carminative disorders, stomachaches, geographic tongue, constipation, appetite stimulants and food poisoning (1.00 each) indicating the best agreement among the informants knowledge of medicinal plants that were used to treat aliments in these categories. The highest fidelity level values were recorded for Punica granatum (100.00), Psidium guajava (95.45), and Gymnopetalum integrifolium (90.91) showing conformity of knowledge on species with the best healing potential. Medicinal plants still play an important role among Karen culture. The present information on these medicinal plants, which have

Dietary acrylamide: What happens during digestion.

Science.gov (United States)

Sansano, M; Heredia, A; Peinado, I; Andrés, A

2017-12-15

Acrylamide is a well-known potentially carcinogen compound formed during thermal processing as an intermediate of Maillard reactions. Three objectives were addressed: the impact of gastric digestion on acrylamide content of French Fries, chips, chicken nuggets, onions rings, breakfast cereals, biscuits, crackers, instant coffee and coffee substitute; the acrylamide content evolution during gastrointestinal digestion of French fries and chips; and the effectiveness of blanching and air-frying on acrylamide mitigation after gastrointestinal digestion. A significant increase (p-value digestion (maximum registered for sweet biscuits, from 30±8 to 150±48µg/kg). However, at the end of the intestinal stage, acrylamide values were statistically similar (p-value=0.132) for French fries and lower than the initial values (before digestion) in potato chips (p-value=0.027). Finally, the low acrylamide content found in blanched and air-fried samples, remained still lower than for deep fried samples even after gastrointestinal digestion. Copyright © 2017 Elsevier Ltd. All rights reserved.

Characterization of the methanogen community in a household anaerobic digester fed with swine manure in China.

Science.gov (United States)

Qin, Huibin; Lang, Huihua; Yang, Hongjiang

2013-09-01

Household anaerobic digesters have been installed across rural China for biogas production, but information on methanogen community structure in these small biogas units is sparsely available. By creating clone libraries for 16S rRNA and methyl coenzyme M reductase alpha subunit (mcrA) genes, we investigated the methanogenic consortia in a household biogas digester treating swine manure. Operational taxonomic units (OTUs) were defined by comparative sequence analysis, seven OTUs were identified in the 16S rRNA gene library, and ten OTUs were identified in the mcrA gene library. Both libraries were dominated by clones highly related to the type strain Methanocorpusculum labreanum Z, 64.0 % for 16S rRNA gene clones and 64.3 % for mcrA gene clones. Additionally, gas chromatography assays showed that formic acid was 84.54 % of the total volatile fatty acids and methane was 57.20 % of the biogas composition. Our results may help further isolation and characterization of methanogenic starter strains for industrial biogas production.

Measurement of true ileal calcium digestibility in meat and bone meal for broiler chickens using the direct method.

Science.gov (United States)

Anwar, M N; Ravindran, V; Morel, P C H; Ravindran, G; Cowieson, A J

2016-01-01

The objective of the study that is presented herein was to determine the true ileal calcium (Ca) digestibility in meat and bone meal (MBM) for broiler chickens using the direct method. Four MBM samples (coded as MBM-1, MBM-2, MBM-3 and MBM-4) were obtained and analyzed for nutrient composition, particle size distribution and bone to soft tissue ratio. The Ca concentrations of MBM-1, MBM-2, MBM-3 and MBM-4 were determined to be 71, 118, 114 and 81 g/kg, respectively. The corresponding geometric mean particle diameters and bone to soft tissue ratios were 0.866, 0.622, 0.875 and 0.781 mm, and 1:1.49, 1:0.98, 1:0.92 and 1:1.35, respectively. Five experimental diets, including four diets with similar Ca concentration (8.3 g/kg) from each MBM and a Ca and phosphorus-free diet, were developed. Meat and bone meal served as the sole source of Ca in the MBM diets. Titanium dioxide (3 g/kg) was incorporated in all diets as an indigestible marker. Each experimental diet was randomly allotted to six replicate cages (eight birds per cage) and offered from d 28 to 31 post-hatch. Apparent ileal Ca digestibility was calculated by the indicator method and corrected for ileal endogenous Ca losses to determine the true ileal Ca digestibility. Ileal endogenous Ca losses were determined to be 88 mg/kg dry matter intake. True ileal Ca digestibility coefficients of MBM-1, MBM-2, MBM-3 and MBM-4 were determined to be 0.560, 0.446, 0.517 and 0.413, respectively. True Ca digestibility of MBM-1 was higher (P 0.05) to that of MBM-3. True Ca digestibility of MBM-2 was similar (P > 0.05) to MBM-3 and MBM-4, while that of MBM-3 was higher (P digestibility in feed ingredients and that Ca in MBM is not highly available as often assumed. The variability in true Ca digestibility of MBM samples could not be attributed to Ca content, percentage bones or particle size. © 2015 Poultry Science Association Inc.

Enhancement and Optimization Mechanisms of Biogas Production for Rural Household Energy in Developing Countries: A review

Directory of Open Access Journals (Sweden)

Yitayal Addis Alemayehu

2015-10-01

Full Text Available Anaerobic digestion is common but vital process used for biogas and fertilizer production as well as one method for waste treatment. The process is currently used in developing countries primarily for biogas production in the household level of rural people. The aim of this review is to indicate possible ways of including rural households who own less than four heads of cattle for the biogas programs in developing countries. The review provides different research out puts on using biogas substrates other than cow dung or its mix through different enhancement and optimization mechanisms. Many biodegradable materials have been studied for alternative methane production. Therefore, these substrates could be used for production by addressing the optimum conditions for each factor and each processes for enhanced and optimized biogas production.

Comparison of various pretreatments for ethanol production enhancement from solid residue after rumen fluid digestion of rice straw.

Science.gov (United States)

Zhang, Haibo; Zhang, Panyue; Ye, Jie; Wu, Yan; Liu, Jianbo; Fang, Wei; Xu, Dong; Wang, Bei; Yan, Li; Zeng, Guangming

2018-01-01

The rumen digested residue of rice straw contains high residual carbohydrates, which makes it a potential cellulosic ethanol feedstock. This study evaluated the feasibility and effectiveness of applying microwave assisted alkali (MAP), ultrasound assisted alkali (UAP), and ball milling pretreatment (BMP) to enhance ethanol production from two digested residues (2.5%-DR and 10%-DR) after rumen fluid digestion of rice straw at 2.5% and 10.0% solid content. Results revealed that 2.5%-DR and 10%-DR had a cellulose content of 36.4% and 41.7%, respectively. MAP and UAP improved enzymatic hydrolysis of digested residue by removing the lignin and hemicellulose, while BMP by decreasing the particle size and crystallinity. BMP was concluded as the suitable pretreatment, resulting in an ethanol yield of 116.65 and 147.42mgg -1 for 2.5%-DR and 10%-DR, respectively. The integrated system including BMP for digested residue at 2.5% solid content achieved a maximum energy output of 7010kJkg -1 . Copyright © 2017 Elsevier Ltd. All rights reserved.

A Meta-Analysis of the Diagnostic Accuracy of Circular RNAs in Digestive System Malignancy.

Science.gov (United States)

Chen, Zhiqiang; Zhang, Long; Han, Guoyong; Zuo, Xueliang; Zhang, Yao; Zhu, Qin; Wu, Jindao; Wang, Xuehao

2018-01-01

Circular RNAs (circRNAs), a novel class of noncoding RNAs, have been found to be dysregulated in various cancers. However, the clinical application value of these circRNAs in digestive system cancers remains to be clarified. We aimed to comprehensively explore the potential role of circRNAs as diagnostic indicators in digestive system malignancies. Relevant studies were systematically retrieved from PubMed, Web of Science and the Cochrane Library. The data that were required to complete 2 × 2 contingency tables were obtained from the included studies. Stratified analyses by cancer type, sample size and publication year were performed. Thirteen studies with 2,276 individuals were included in the meta-analysis. The pooled sensitivity and specificity of circRNAs in the diagnosis of digestive system malignancy were 0.72 [95% confidence interval (CI): 0.65-0.77] and 0.77 (95% CI: 0.72-0.81), respectively. The overall positive likelihood ratio was 3.09 (95% CI: 2.64-3.62), and the overall negative likelihood ratio was 0.37 (95% CI: 0.31-0.44). The pooled diagnostic odds ratio was 8.38 (95% CI: 6.86-10.25), and the overall area under the curve was 0.81 (95% CI: 0.77-0.84), indicating good discriminative ability of circRNAs as biomarkers for digestive system malignancy. circRNAs distinguish patients with digestive system cancer from controls with relatively high diagnostic accuracy. circRNAs may be used as potential biomarkers for the diagnosis of digestive system malignancy. © 2018 The Author(s). Published by S. Karger AG, Basel.

Headway on co-digestion of wastes

International Nuclear Information System (INIS)

Gokhale, Yogeshwar

2013-01-01

Full text: Many wastewater treatment plants (WWTPs) in Australia produce biogas either directly from the wastewater or from anaerobic digestion of the primary and/or secondary sludge, which in turn is used to create energy. Some WWTPs produce electricity from the biogas to either support the treatment plant or to export the electricity to the grid or both. High-strength organic wastes such as fats, oil and grease, food waste, commercial (restaurant) waste and brewery waste are attractive biogas sources that can be realised through co-digestion with the sludge from wastewater treatment. Co-digestion of high-strength waste can be a tricky business due to the varying nature of the waste, special handling requirements, and potential digester process issues like foaming. However, experiences over the past decade have helped identify mitigation measures and advanced designs to reduce these risks. Several WWTPs in the US accept fats, oil and grease (FOG) as a feedstock for co-digestion, and CH2M Hill has been involved in various capacities on some of those projects. The Douglas L. Smith Middle Basin Wastewater Treatment Plant (WWTP) in Johnson County, Kansas, includes an environmentally friendly approach for the treatment of FOG wastes from local restaurants and industrial sources. FOG waste receipts are handled using a separate onsite liquid receiving facility, and the FOG tanks and pipes are heated to minimise clogging. Co-digestion of FOG enhanced the gas production to fuel a 2.1 megawatt biogas co-generation system. Other CH2M Hill FOG co-digestion projects are FOG addition to the incinerator at the Hampton Roads Sanitation District in Virginia; FOG co-digestion at the Pinellas County in Florida; and FOG co-digestion and co-generation at the Essex Junction in Vermont. This experience was recently expanded to the co-digestion of other high-strength organic waste for Yarra Valley Water (YVW) and City West Water (CWW) in Victoria. The potential high-strength waste

Steam Digest 2002

Energy Technology Data Exchange (ETDEWEB)

2003-11-01

Steam Digest 2002 is a collection of articles published in the last year on steam system efficiency. DOE directly or indirectly facilitated the publication of the articles through it's BestPractices Steam effort. Steam Digest 2002 provides a variety of operational, design, marketing, and program and program assessment observations. Plant managers, engineers, and other plant operations personnel can refer to the information to improve industrial steam system management, efficiency, and performance.

The co-digestion of animal manure and food industry residues in the UK. The role of the NFFO as a catalyst

Energy Technology Data Exchange (ETDEWEB)

Lukehurste, C T

1997-08-01

The adoption of AD (anaerobig digestion) in the UK has been sporadic and limited to small installations or farms. In 1993 the North Tamar LEADER Project embarked on the first large scale community initiative to use AD as an instrument for environmental management and integrated rural development. At the same time a new turn-key construction company began to use the NFFO process to stimulate AD adoption and sales. This paper examines the two approaches and their contribution of the NFFO process. (au)

Kinetics and dynamic modelling of batch anaerobic digestion of municipal solid waste in a stirred reactor

International Nuclear Information System (INIS)

Nopharatana, Annop; Pullammanappallil, Pratap C.; Clarke, William P.

2007-01-01

A series of batch, slurry anaerobic digestion experiments were performed where the soluble and insoluble fractions, and unwashed MSW were separately digested in a 200 l stirred stainless steel vessel at a pH of 7.2 and a temperature of 38 deg. C. It was found that 7% of the total MSW COD was readily soluble, of which 80% was converted to biogas; 50% of the insoluble fraction was solubilised, of this only 80% was converted to biogas. The rate of digesting the insoluble fraction was about four times slower than the rate of digesting the soluble fraction; 48% of the total COD was converted to biogas and 40% of the total nitrogen was converted to ammonia. Soluble and insoluble fractions were broken down simultaneously. The minimum time to convert 95% of the degradable fraction to biogas was 20 days. The lag phase for the degradation of insoluble fraction of MSW can be overcome by acclimatising the culture with the soluble fraction. The rate of digestion and the methane yield was not affected by particle size (within the range of 2-50 mm). A dynamic model was developed to describe batch digestion of MSW. The parameters of the model were estimated using data from the separate digestion of soluble and insoluble fractions and validated against data from the digestion of unwashed MSW. Trends in the specific aceticlastic and formate-utilising methanogenic activity were used to estimate initial methanogenic biomass concentration and bacterial death rate coefficient. The kinetics of hydrolysis of insoluble fraction could be adequately described by a Contois equation and the kinetics of acidogenesis, and aceticlastic and hydrogen utilising methanogenesis by Monod equations

Anaerobic Digestion: Mass Balances and Products

DEFF Research Database (Denmark)

Møller, Jacob; Christensen, Thomas Højlund; Jansen, Jes la Cour

2011-01-01

While the basic processes involved in anaerobic digestion of waste are described in Chapter 9.4 and the main digestion technologies are presented in Chapter 9.5, this chapter focuses on mass balances, gas production and energy aspects, environmental emissions and unit process inventories. Underst......While the basic processes involved in anaerobic digestion of waste are described in Chapter 9.4 and the main digestion technologies are presented in Chapter 9.5, this chapter focuses on mass balances, gas production and energy aspects, environmental emissions and unit process inventories...

Mammalian mucosal α-glucosidases coordinate with α-amylase in the initial starch hydrolysis stage to have a role in starch digestion beyond glucogenesis.

Science.gov (United States)

Dhital, Sushil; Lin, Amy Hui-Mei; Hamaker, Bruce R; Gidley, Michael J; Muniandy, Anbuhkani

2013-01-01

Starch digestion in the human body is typically viewed in a sequential manner beginning with α-amylase and followed by α-glucosidase to produce glucose. This report indicates that the two enzyme types can act synergistically to digest granular starch structure. The aim of this study was to investigate how the mucosal α-glucosidases act with α-amylase to digest granular starch. Two types of enzyme extracts, pancreatic and intestinal extracts, were applied. The pancreatic extract containing predominantly α-amylase, and intestinal extract containing a combination of α-amylase and mucosal α-glucosidase activities, were applied to three granular maize starches with different amylose contents in an in vitro system. Relative glucogenesis, released maltooligosaccharide amounts, and structural changes of degraded residues were examined. Pancreatic extract-treated starches showed a hydrolysis limit over the 12 h incubation period with residues having a higher gelatinization temperature than the native starch. α-Amylase combined with the mucosal α-glucosidases in the intestinal extract showed higher glucogenesis as expected, but also higher maltooligosaccharide amounts indicating an overall greater degree of granular starch breakdown. Starch residues after intestinal extract digestion showed more starch fragmentation, higher gelatinization temperature, higher crystallinity (without any change in polymorph), and an increase of intermediate-sized or small-sized fractions of starch molecules, but did not show preferential hydrolysis of either amylose or amylopectin. Direct digestion of granular starch by mammalian recombinant mucosal α-glucosidases was observed which shows that these enzymes may work either independently or together with α-amylase to digest starch. Thus, mucosal α-glucosidases can have a synergistic effect with α-amylase on granular starch digestion, consistent with a role in overall starch digestion beyond their primary glucogenesis function.

Mammalian mucosal α-glucosidases coordinate with α-amylase in the initial starch hydrolysis stage to have a role in starch digestion beyond glucogenesis.

Directory of Open Access Journals (Sweden)

Sushil Dhital

Full Text Available Starch digestion in the human body is typically viewed in a sequential manner beginning with α-amylase and followed by α-glucosidase to produce glucose. This report indicates that the two enzyme types can act synergistically to digest granular starch structure. The aim of this study was to investigate how the mucosal α-glucosidases act with α-amylase to digest granular starch. Two types of enzyme extracts, pancreatic and intestinal extracts, were applied. The pancreatic extract containing predominantly α-amylase, and intestinal extract containing a combination of α-amylase and mucosal α-glucosidase activities, were applied to three granular maize starches with different amylose contents in an in vitro system. Relative glucogenesis, released maltooligosaccharide amounts, and structural changes of degraded residues were examined. Pancreatic extract-treated starches showed a hydrolysis limit over the 12 h incubation period with residues having a higher gelatinization temperature than the native starch. α-Amylase combined with the mucosal α-glucosidases in the intestinal extract showed higher glucogenesis as expected, but also higher maltooligosaccharide amounts indicating an overall greater degree of granular starch breakdown. Starch residues after intestinal extract digestion showed more starch fragmentation, higher gelatinization temperature, higher crystallinity (without any change in polymorph, and an increase of intermediate-sized or small-sized fractions of starch molecules, but did not show preferential hydrolysis of either amylose or amylopectin. Direct digestion of granular starch by mammalian recombinant mucosal α-glucosidases was observed which shows that these enzymes may work either independently or together with α-amylase to digest starch. Thus, mucosal α-glucosidases can have a synergistic effect with α-amylase on granular starch digestion, consistent with a role in overall starch digestion beyond their primary

Mammalian Mucosal α-Glucosidases Coordinate with α-Amylase in the Initial Starch Hydrolysis Stage to Have a Role in Starch Digestion beyond Glucogenesis

Science.gov (United States)

Dhital, Sushil; Lin, Amy Hui-Mei; Hamaker, Bruce R.; Gidley, Michael J.; Muniandy, Anbuhkani

2013-01-01

Starch digestion in the human body is typically viewed in a sequential manner beginning with α-amylase and followed by α-glucosidase to produce glucose. This report indicates that the two enzyme types can act synergistically to digest granular starch structure. The aim of this study was to investigate how the mucosal α-glucosidases act with α-amylase to digest granular starch. Two types of enzyme extracts, pancreatic and intestinal extracts, were applied. The pancreatic extract containing predominantly α-amylase, and intestinal extract containing a combination of α-amylase and mucosal α-glucosidase activities, were applied to three granular maize starches with different amylose contents in an in vitro system. Relative glucogenesis, released maltooligosaccharide amounts, and structural changes of degraded residues were examined. Pancreatic extract-treated starches showed a hydrolysis limit over the 12 h incubation period with residues having a higher gelatinization temperature than the native starch. α-Amylase combined with the mucosal α-glucosidases in the intestinal extract showed higher glucogenesis as expected, but also higher maltooligosaccharide amounts indicating an overall greater degree of granular starch breakdown. Starch residues after intestinal extract digestion showed more starch fragmentation, higher gelatinization temperature, higher crystallinity (without any change in polymorph), and an increase of intermediate-sized or small-sized fractions of starch molecules, but did not show preferential hydrolysis of either amylose or amylopectin. Direct digestion of granular starch by mammalian recombinant mucosal α-glucosidases was observed which shows that these enzymes may work either independently or together with α-amylase to digest starch. Thus, mucosal α-glucosidases can have a synergistic effect with α-amylase on granular starch digestion, consistent with a role in overall starch digestion beyond their primary glucogenesis function. PMID

Digestibilidade da silagem de grãos úmidos de milho com diferentes granulometrias para suínos Digestibility of high moisture corn grain silage with different particle size for swines

Directory of Open Access Journals (Sweden)

A.C. Lohmann

2010-02-01

Full Text Available Avaliou-se a composição química e determinaram-se os valores de energia digestível (ED e metabolizável (EM, os coeficientes de digestibilidade da matéria seca (CDMS, da proteína bruta (CDPB, da matéria mineral (CDMM; do extrato etéreo (CDEE; da fibra bruta (CDFB, da energia bruta (CDEB e do extrativo não nitrogenado (CDENN e os coeficientes de digestibilidade (CDEB e metabolizabilidade da energia bruta (CMEB da silagem de grãos úmidos de milho (SGUM. Foram utilizados 20 suínos, com peso vivo inicial de 28,89±4,9kg, distribuídos em gaiolas de metabolismo. Foi utilizada uma única SGUM, com quatro diferentes granulometrias 513, 587, 717 e 1363µm, que substituiu em 30% a dieta-referência. Os CDMS, CDPB, CDEE, CDMM e CDENN diminuíram com o aumento da granulometria da SGUM. Os CDEB e CMEB também diminuíram de 89,0 para 94,3%, e de 82,9 para 88,5%, respectivamente. Os valores energéticos variaram de 4439 a 4493kcal EB/kg, de 3999 a 4194kcal ED/kg e de 3729 a 3939kcal EM/kg, na matéria seca. Os CDEB e CMEB se reduziram até os diâmetros geométricos médios de 754 e 831µm, respectivamente. A digestibilidade dos nutrientes da SGUM foi influenciada negativamente ao se aumentar o diâmetro geométrico médio das partículas.The chemical composition; the values of digestible (DE and metabolizable (ME energy; the coefficients of digestibility of dry matter (CDDM, crude protein (CDCP, mineral matter (CDMM, ether extract (CDEE, crude fiber (CDFB, crude energy (CDCE, and non nitrogen extractive (CDENN; as well as the coefficient of metabolizability of gross energy (CMGE of high moisture corn grain silage (HMCGS were evaluated. Twenty swines, averaging 28.89±4.9kg of live weight, randomly allotted in metabolism cages were used. HMCGS with different particle sizes 513, 587, 717, and 1363µm, replacing 30% of basal diet was used. CDDM, CDCP, CDEE, CDMM, and CDENN decreased as the particle size of the HMCGS increased. CDGE and CMGE also

[Changes in prices of taxed sugar-sweetened beverages and nonessential energy dense food in rural and semi-rural areas in Mexico].

Science.gov (United States)

Colchero, M Arantxa; Zavala, J Alejandro; Batis, Carolina; Shamah-Levy, Teresa; Rivera-Dommarco, Juan A

2017-01-01

To estimate changes in prices associated with the implementation of the tax to sugar sweetened beverages (SSB) and to nonessential energy dense food in 2014. Price data were collected in rural and semi-rural areas in December 2013, and April and December 2014. Fixed effects models were used to estimate changes in prices of beverages and nonessential energy dense food, stratified by region, retailer and package size. The SSB tax did not pass completely through prices: prices increased on average 0.73 pesos per liter. For nonessential energy dense food, the tax passed completely or was overshifted for cookies, cereal bars and cereal boxes. The potential effect of the taxes on consumption could be attenuated in rural areas as the pass through prices was incomplete.

Digestive oncologist in the gastroenterology training curriculum

Science.gov (United States)

Mulder, Chris Jacob Johan; Peeters, Marc; Cats, Annemieke; Dahele, Anna; Droste, Jochim Terhaar sive

2011-01-01

Until the late 1980s, gastroenterology (GE) was considered a subspecialty of Internal Medicine. Today, GE also incorporates Hepatology. However, Digestive Oncology training is poorly defined in the Hepatogastroenterology (HGE)-curriculum. Therefore, a Digestive Oncology curriculum should be developed and this document might be a starting point for such a curriculum. HGE-specialists are increasingly resisting the paradigm in which they play only a diagnostic and technical role in the management of digestive tumors. We suggest minimum end-points in the standard HGE-curriculum for oncology, and recommend a focus year in the Netherlands for Digestive Oncology in the HGE-curriculum. To produce well-trained digestive oncologists, an advanced Digestive Oncology training program with specific qualifications in Digestive Oncology (2 years) has been developed. The schedule in Belgium includes a period of at least 6 mo to be spent in a medical oncology department. The goal of these programs remains the production of well-trained digestive oncologists. HGE specialists are part of the multidisciplinary oncological teams, and some have been administering chemotherapy in their countries for years. In this article, we provide a road map for the organization of a proper training in Digestive Oncology. We hope that the World Gastroenterology Organisation and other (inter)national societies will support the necessary certifications for this specific training in the HGE-curriculum. PMID:21556128

Size distribution of atmospheric Pb and 210Pb in rural New Jersey: implications for wet and dry deposition

International Nuclear Information System (INIS)

Knuth, R.H.; Knutson, E.O.; Feely, H.W.; Volchok, H.L.

1983-01-01

High volume cascade impactor samples taken during spring, 1980, at the Chester sampling station in northern New Jersey showed a small but persistent difference in the size distributions of Pb and 210 Pb. On the average, 69% of Pb was below 0.58 μm and 12% was above 3.45 μm. For 210 Pb, the corresponding figures were 71% and 2.8%. These 210 Pb data indicate larger particles than found in Colorado, but smaller than those found over the Mediterranean Sea. The average air concentrations for the two species were 111 ng/m 3 (Pb) and 10.9 fCi/m 3 ( 210 Pb), in good agreement with other reported results for rural northeast areas. Experimental results imply a factor of three difference in dry deposition velocity between the two species, providing a qualitative explanation of a previously observed difference in wet/dry deposition of the two species. 19 references, 1 figure, 6 tables

Lewy Body Digest eNewsletter

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... resources Join the fight against LBD! Donate Lewy Digest Click here to subscribe today to receive regular ... research in Lewy body dementia. April 2018 Lewy Digest Month of Compassion Caregiver Spotlight Research Centers of ...

Anaerobic digestion for sustainable development: a natural approach

Energy Technology Data Exchange (ETDEWEB)

Gijzen, H.J.

2002-07-01

After the discovery of methane gas by Alessandro Volta in 1776, it took about 100 years before anaerobic processes for the treatment of wastewater and sludges were introduced. The development of high rate anaerobic digesters for the treatment of sewage and industrial wastewater took until the nineteen-seventies and for solid waste even till the nineteen-eighties. All digesters have in common that they apply natural anaerobic consortia of microorganisms for degradation and transformation processes. In view of this, it could be rewarding to evaluate the efficiency of natural ecosystems for their possible application. Examples of high rate anaerobic natural systems include the forestomach of ruminants and the hindgut of certain insects, such as termites and cockroaches. These ''natural reactors'' exhibit volumetric methane production rates as high as 35 l/l.d. The development of anaerobic reactors based on such natural anaerobic systems could produce eco-technologies for the effective management of a wide variety of solid wastes and industrial wastewater. Important limitations of anaerobic treatment of domestic sewage relate to the absence of nutrient and pathogen removal. A combination of anaerobic pre-treatment followed by photosynthetic post-treatment is proposed for the effective recovery of energy and nutrients from sewage. This eco-technology approach is based on the recognition that the main nutrient assimilating capacity is housed in photosynthetic plants. The proposed anaerobic-photosynthetic process is energy efficient, cost effective and applicable under a wide variety of rural and urban conditions. In conclusion: a natural systems approach towards waste management could generate affordable eco-technologies for effective treatment and resource recovery. (author)

Particle size distribution of rice flour affecting the starch enzymatic hydrolysis and hydration properties.

Science.gov (United States)

de la Hera, Esther; Gomez, Manuel; Rosell, Cristina M

2013-10-15

Rice flour is becoming very attractive as raw material, but there is lack of information about the influence of particle size on its functional properties and starch digestibility. This study evaluates the degree of dependence of the rice flour functional properties, mainly derived from starch behavior, with the particle size distribution. Hydration properties of flours and gels and starch enzymatic hydrolysis of individual fractions were assessed. Particle size heterogeneity on rice flour significantly affected functional properties and starch features, at room temperature and also after gelatinization; and the extent of that effect was grain type dependent. Particle size heterogeneity on rice flour induces different pattern in starch enzymatic hydrolysis, with the long grain having slower hydrolysis as indicated the rate constant (k). No correlation between starch digestibility and hydration properties or the protein content was observed. It seems that in intact granules interactions with other grain components must be taken into account. Overall, particle size fractionation of rice flour might be advisable for selecting specific physico-chemical properties. Copyright © 2013. Published by Elsevier Ltd.

The repeatability of individual nutrient digestibility in pigs

NARCIS (Netherlands)

Ouweltjes, W.; Verschuren, L.M.G.; Pijlman, J.; Bergsma, R.; Schokker, D.; Knol, E.F.; Aar, van der P.J.; Molist, F.; Calus, M.P.L.

2018-01-01

Digestibility of nutrients in pig diets is an important component of overall feed efficiency. Targeted improvement of digestibility is currently mainly achieved by optimization of pig diets, based on information generated from digestibility trials that aim to establish fecal digestibility

High-solids anaerobic co-digestion of sewage sludge and food waste in comparison with mono digestions: stability and performance.

Science.gov (United States)

Dai, Xiaohu; Duan, Nina; Dong, Bin; Dai, Lingling

2013-02-01

System stability and performance of high-solids anaerobic co-digestion of dewatered sludge (DS) and food waste (FW) in comparison with mono digestions were investigated. System stability was improved in co-digestion systems with co-substrate acting as a diluting agent to toxic chemicals like ammonia or Na(+). For high-solids digestion of DS, the addition of FW not only improved system stability but also greatly enhanced volumetric biogas production. For high-solids digestion of FW, the addition of DS could reduce Na(+) concentration and help maintain satisfactory stability during the conversion of FW into biogas. System performances of co-digestion systems were mainly determined by the mixing ratios of DS and FW. Biogas production and volatile solids (VSs) reduction in digestion of the co-mixture of DS and FW increased linearly with higher ratios of FW. A kinetic model, which aimed to forecast the performance of co-digestion and to assist reactor design, was developed from long-term semi-continuous experiments. Maximum VS reduction for DS and FW was estimated to be 44.3% and 90.3%, respectively, and first order constant k was found to be 0.17d(-1) and 0.50 d(-1), respectively. Experimental data of co-digestion were in good conformity to the predictions of the model. Copyright © 2012 Elsevier Ltd. All rights reserved.

Personal Relationships and Digestive Disorders

Science.gov (United States)

... Teens Manage Your Health Finding a Doctor The Digestive System Symptoms & Causes How to Prepare for Tests ... Part in Studies Resources Publications Library En Español Digestive Health Matters Medical Definitions Links Books of Interest ...

Anaerobic Digestion Scale Levels and Their Energy Yields. A comparison of energy yields of different manure-and co-digestion scale levels

NARCIS (Netherlands)

Konneman, Bram

2007-01-01

Anaerobic digestion is a biological process whereby, in the absence of oxygen, organic matter is converted into biogas and digestate. In recent years anaerobic digestion has received re-newed attention in the Dutch agricultural sector. Co-digestion, in wh

Stability and in vitro digestibility of emulsions containing lecithin and whey proteins.

Science.gov (United States)

Mantovani, Raphaela Araujo; Cavallieri, Ângelo Luiz Fazani; Netto, Flavia Maria; Cunha, Rosiane Lopes

2013-09-01

The effect of pH and high-pressure homogenization on the properties of oil-in-water (O/W) emulsions stabilized by lecithin and/or whey proteins (WPI) was evaluated. For this purpose, emulsions were characterized by visual analysis, droplet size distribution, zeta potential, electrophoresis, rheological measurements and their response to in vitro digestion. Lecithin emulsions were stable even after 7 days of storage and WPI emulsions were unstable only at pH values close to the isoelectric point (pI) of proteins. Systems containing the mixture of lecithin and WPI showed high kinetic instability at pH 3, which was attributed to the electrostatic interaction between the emulsifiers oppositely charged at this pH value. At pH 5.5 and 7, the mixture led to reduction of the droplet size with enhanced emulsion stability compared to the systems with WPI or lecithin. The stability of WPI emulsions after the addition of lecithin, especially at pH 5.5, was associated with the increase of droplet surface charge density. The in vitro digestion evaluation showed that WPI emulsion was more stable against gastrointestinal conditions.

Semi-continuous anaerobic co-digestion of cow manure and steam-exploded Salix with recirculation of liquid digestate.

Science.gov (United States)

Estevez, Maria M; Sapci, Zehra; Linjordet, Roar; Schnürer, Anna; Morken, John

2014-04-01

The effects of recirculating the liquid fraction of the digestate during mesophilic anaerobic co-digestion of steam-exploded Salix and cow manure were investigated in laboratory-scale continuously stirred tank reactors. An average organic loading rate of 2.6 g VS L(-1) d(-1) and a hydraulic retention time (HRT) of 30 days were employed. Co-digestion of Salix and manure gave better methane yields than digestion of manure alone. Also, a 16% increase in the methane yield was achieved when digestate was recirculated and used instead of water to dilute the feedstock (1:1 dilution ratio). The reactor in which the larger fraction of digestate was recirculated (1:3 dilution ratio) gave the highest methane yields. Ammonia and volatile fatty acids did not reach inhibitory levels, and some potentially inhibitory compounds released during steam explosion (i.e., furfural and 5-hydroxy methyl furfural) were only detected at trace levels throughout the entire study period. However, accumulation of solids, which was more pronounced in the recycling reactors, led to decreased methane yields in those systems after three HRTs. Refraining from the use of fresh water to dilute biomass with a high-solids content and obtaining a final digestate with increased dry matter content might offer important economic benefits in full-scale processes. To ensure long-term stability in such an approach, it would be necessary to optimize separation of the fraction of digestate to be recirculated and also perform proper monitoring to avoid accumulation of solids. Copyright © 2014 Elsevier Ltd. All rights reserved.

Co-digestion of ley crop silage, straw and manure

Energy Technology Data Exchange (ETDEWEB)

Nordberg, Aa; Edstroem, M [Swedish Inst. of Agricultural Engineering, Uppsala (Sweden)

1997-08-01

Anaerobic co-digestion of ley crop silage, wheat straw and liquid manure with liquid recirculation was investigated in laboratory- and pilot scale. An organic loading rate of 6.0 g Vs L{sup -1} d{sup -1} was obtained when 20% of liquid manure (TS-basis) was added, whereas an organic loading rate of 2.5 g VS L{sup -1} d{sup -1} was obtained when the manure was replaced with a trace element solution. The methane yield varied between 0.28 and 0.32 L g VS{sup -1}, with the value being lowest for a mixture containing 60% silage, 20% straw and 20% manure (TS-basis), and highest for 100% ley crop silage. The concentration of ammonia-N was maintained at ca 2 g L{sup -1} by adjusting the C:N-ratio with straw. To achieve good mixing characteristics with a reasonable energy input at TS-concentrations around 10%, the particle sizes of straw and silage had to be reduced with a meat mincer. The digester effluent was dewatered, resulting in a solid phase that could be composted without having to add amendments or bulking agents, and a liquid phase containing 7-8% TS (mainly soluble and suspended solids). The liquid phase, which should be used as an organic fertilizer, contained up to 90% of the N and 74% of the P present in the residues. Calculations of the costs for a full-scale plant showed that a biogas price of SEK 0.125 MJ{sup -1} (0.45 k Wh{sup -1}) is necessary to balance the costs of a 1-MW plant. An increase in plant size to 4 MW together with an increase in compost price from SEK 100 tonnes{sup -1} to SEK 370 tonnes{sup -1} and a 20% rise in the methane yield through post-digestion (20%) would decrease the price to SEK 0.061 MJ{sup -1} (0.22 kWh{sup -1}). (au) 15 refs.

Macroscopic digestive tract anatomy of two small antelopes, the blackbuck (Antilope cervicapra) and the Arabian sand gazelle (Gazella subgutturosa marica)

DEFF Research Database (Denmark)

Sauer, Cathrine; Bertelsen, Mads Frost; Hammer, Sven

2016-01-01

The digestive tract anatomy of 14 blackbucks (Antilope cervicapra) and 7 Arabian sand gazelles (Gazella subgutturosa marica) was quantified by dimensions, area and weight. Data from the two small-sized antilopinae were evaluated against a larger comparative data set from other ruminants classified...... as having either a ‘cattle-type’ or ‘moose-type’ digestive system. The digestive anatomy of the blackbuck resembled that of 'cattle-type' ruminants, which corresponds to their feeding ecology and previous studies of solute and particle retention time; however, a surprising exception was the remarkably small...... time had led to the expectation of a more 'cattle-type' anatomy. The results show that outliers to general morphological trends exist, that findings on physiology and anatomy do not always match completely, and that differences in the digestive morphology among ruminant species are more difficult...

Brain size and urbanization in birds

Institute of Scientific and Technical Information of China (English)

Anders; Pape; M?ller; Johannes; Erritz?e

2015-01-01

Background: Brain size may affect the probability of invasion of urban habitats if a relatively larger brain entails superior ability to adapt to novel environments. However, once urbanized urban environments may provide poor quality food that has negative consequences for normal brain development resulting in an excess of individuals with small brains.Methods: Here we analyze the independent effects of mean, standard deviation and skewness in brain mass for invasion of urban habitats by 108 species of birds using phylogenetic multiple regression analyses weighted by sample size.Results: There was no significant difference in mean brain mass between urbanized and non-urbanized species or between urban and rural populations of the same species, and mean brain mass was not significantly correlated with time since urbanization. Bird species that became urbanized had a greater standard deviation in brain mass than non-urbanized species, and the standard deviation in brain mass increased with time since urbanization. Brain mass was significantly left skewed in species that remained rural, while there was no significant skew in urbanized species. The degree of left skew was greater in urban than in rural populations of the same species, and successfully urbanized species decreased the degree of left skew with time since urbanization. This is consistent with the hypothesis that sub-optimal brain development was more common in rural habitats resulting in disproportionately many individuals with very smal brains.Conclusions: These findings do not support the hypothesis that large brains promote urbanization, but suggest that skewness has played a role in the initial invasion of urban habitats, and that variance and skew in brain mass have increased as species have become urbanized.

Brain size and urbanization in birds

Institute of Scientific and Technical Information of China (English)

Anders Pape Mller; Johannes Erritze

2015-01-01

Background:Brain size may affect the probability of invasion of urban habitats if a relatively larger brain entails superior ability to adapt to novel environments. However, once urbanized urban environments may provide poor quality food that has negative consequences for normal brain development resulting in an excess of individuals with small brains. Methods:Here we analyze the independent effects of mean, standard deviation and skewness in brain mass for invasion of urban habitats by 108 species of birds using phylogenetic multiple regression analyses weighted by sample size. Results:There was no significant difference in mean brain mass between urbanized and non-urbanized species or between urban and rural populations of the same species, and mean brain mass was not significantly correlated with time since urbanization. Bird species that became urbanized had a greater standard deviation in brain mass than non-urbanized species, and the standard deviation in brain mass increased with time since urbanization. Brain mass was significantly left skewed in species that remained rural, while there was no significant skew in urbanized species. The degree of left skew was greater in urban than in rural populations of the same species, and successfully urbanized species decreased the degree of left skew with time since urbanization. This is consistent with the hypothesis that sub-optimal brain development was more common in rural habitats resulting in disproportionately many individuals with very smal brains. Conclusions:These findings do not support the hypothesis that large brains promote urbanization, but suggest that skewness has played a role in the initial invasion of urban habitats, and that variance and skew in brain mass have increased as species have become urbanized.

Anaerobic Digestion Alters Copper and Zinc Speciation.

Science.gov (United States)

Legros, Samuel; Levard, Clément; Marcato-Romain, Claire-Emmanuelle; Guiresse, Maritxu; Doelsch, Emmanuel

2017-09-19

Anaerobic digestion is a widely used organic waste treatment process. However, little is known on how it could alter the speciation of contaminants in organic waste. This study was focused on determining the influence of anaerobic digestion on the speciation of copper and zinc, two metals that generally occur at high concentration in organic waste. Copper and zinc speciation was investigated by X-ray absorption spectroscopy in four different raw organic wastes (predigestion) and their digested counterparts (postdigestion, i.e., digestates). The results highlighted an increase in the digestates of the proportion of amorphous or nanostructured copper sulfides as well as amorphous or nanostructured zinc sulfides and zinc phosphate as compared to raw waste. We therefore suggest that the environmental fate of these elements would be different when spreading either digestates or raw waste on cropland.

Application of Methanobrevibacter acididurans in anaerobic digestion.

Science.gov (United States)

Savant, D V; Ranade, D R

2004-01-01

To operate anaerobic digesters successfully under acidic conditions, hydrogen utilizing methanogens which can grow efficiently at low pH and tolerate high volatile fatty acids (VFA) are desirable. An acid tolerant hydrogenotrophic methanogen viz. Methanobrevibacter acididurans isolated from slurry of an anaerobic digester running on alcohol distillery wastewater has been described earlier by this lab. This organism could grow optimally at pH 6.0. In the experiments reported herein, M. acididurans showed better methanogenesis under acidic conditions with high VFA, particularly acetate, than Methanobacterium bryantii, a common hydrogenotrophic inhabitant of anaerobic digesters. Addition of M. acididurans culture to digesting slurry of acidogenic as well as methanogenic digesters running on distillery wastewater showed increase in methane production and decrease in accumulation of volatile fatty acids. The results proved the feasibility of application of M. acididurans in anaerobic digesters.

Small-scale household biogas digesters

DEFF Research Database (Denmark)

Bruun, Sander; Jensen, Lars Stoumann; Khanh Vu, Van Thi

2014-01-01

There are a number of advantages to small-scale biogas production on farms, including savings on firewood or fossil fuels and reductions in odour and greenhouse gas emissions. For these reasons, governments and development aid agencies have supported the installation of biogas digesters. However......, biogas digesters are often poorly managed and there is a lack of proper distribution systems for biogas. This results in methane being released inadvertently through leaks in digesters and tubing, and intentionally when production exceeds demand. As methane has a global warming potential 25 times greater......% of the produced biogas is released, depending on the type of fuel that has been replaced. The limited information available as regards methane leaking from small-scale biogas digesters in developing countries indicates that emissions may be as high as 40%. With the best estimates of global numbers of small...

Waste minimization through high-pressure microwave digestion of soils for gross α/β analyses

International Nuclear Information System (INIS)

Yaeger, J.S.; Smith, L.L.

1995-04-01

As a result of the U.S. Department of Energy's (DOE) environmental restoration and waste management activities, laboratories receive numerous analytical requests for gross α/β analyses. Traditional sample preparation methods for gross α/β analysis of environmental and mixed waste samples require repetitive leaching, which is time consuming and generates large volumes of secondary wastes. An alternative to leaching is microwave digestion. In the past. microwave technology has had limited application in the radiochemical laboratory because of restrictions on sample size resulting from vessel pressure limitations. However, new microwave vessel designs allow for pressures on the order of 11 MPa (1500 psi). A procedure is described in which microwave digestion is used to prepare environmental soil samples for gross α/β analysis. Results indicate that the described procedure meets performance requirements for several soil types and is equivalent to traditional digestion techniques. No statistical differences at the 95% confidence interval exist between the measurement on samples prepared from the hot plate and microwave digestion procedures for those soils tested. Moreover, microwave digestion allows samples to be prepared in a fraction of the time with significantly less acid and with lower potential of cross-contamination. In comparison to the traditional hot plate method, the waste volumes required for the microwave procedure are a factor of 10 lower, while the analyst time for sample processing is at least a factor of three lower

Fertilizer and sanitary quality of digestate biofertilizer from the co-digestion of food waste and human excreta.

Science.gov (United States)

Owamah, H I; Dahunsi, S O; Oranusi, U S; Alfa, M I

2014-04-01

This research was aimed at assessing the fertilizer quality and public health implications of using digestate biofertilizer from the anaerobic digestion of food wastes and human excreta. Twelve (12) kg of food wastes and 3kg of human excreta were mixed with water in a 1:1 w/v to make 30-l slurry that was fed into the anaerobic digester to ferment for 60days at mesophilic temperature (22-31°C). Though BOD, COD, organic carbon and ash content in the feedstock were reduced after anaerobic digestion by 50.0%, 10.6%, 74.3% and 1.5% respectively, nitrogen, pH and total solids however increased by 12.1%, 42.5% and 12.4% respectively. The C/N ratios of the feedstock and compost are 135:1 and 15.8:1. The residual total coliforms of 2.10×10(8)CFU/100ml in the digestate was above tolerable limits for direct application on farmlands. Microbial analysis of the digestate biofertilizer revealed the presence of Pseudomonas, Klebsiella, Clostridium, Bacillus, Bacteroides, Penicillum, Salmollena, and Aspergillus. Klebsiella, Bacillus, Pseudomonas, Penicillum and Aspergillus can boost the efficiency of the biofertilizer through nitrogen fixation and nutrient solubility in soils but Klebsiella again and Salmollena are potential health risks to end users. Further treatment of the digestate for more efficient destruction of pathogens is advised. Copyright © 2014 Elsevier Ltd. All rights reserved.

Energy and GHG Analysis of Rural Household Biogas Systems in China

Directory of Open Access Journals (Sweden)

Lixiao Zhang

2014-02-01

Full Text Available The Chinese government has taken great efforts to popularize rural household scale biogas digesters, since they are regarded as an effective approach to address energy shortage issues in rural areas and as a potential way of reducing greenhouse gas (GHG emissions. Focusing on a typical rural household biogas system, the aim of this study is to systematically quantify its total direct and indirect energy, concentrating on non-renewable energy and the associated GHG emission cost over the entire life cycle to understand its net dynamic benefits. The results show that the total energetic cost for biogas output is 2.19 J/J, of which 0.56 J is from non-renewable energy sources and the GHG emission cost is 4.54 × 10−5 g CO2-equivalent (CO2-eq, with respect to its design life cycle of 20 years. Correspondingly, a net non-renewable energy saving of 9.89 × 1010 J and GHG emission reduction of 50.45 t CO2-eq can be obtained considering the coal substitution and manure disposal. However, it must be run for at least 10 and 3 years, to obtain positive net non-renewable energy savings and GHG emission reduction benefits, respectively. These results have policy implications for development orientation, follow-up services, program management and even national financial subsidy methods.

Efeito da granulometria do bagaço de cana sobre as características digestivas e a contribuição nutritiva dos cecotrofos Effect particle size of sugar cane bagasse on the digestive traits and the cecotrophes nutritive contribution

Directory of Open Access Journals (Sweden)

Flávia da Silva Vieira

2003-08-01

Full Text Available Foram realizados dois experimentos com coelhos mestiços Nova Zelândia Branco x Califórnia, com o objetivo de avaliar o efeito da granulometria da fonte de fibra sobre as características digestivas de coelhos em crescimento e sobre a produção, composição química e a contribuição nutritiva dos cecotrofos, em termos de matéria seca (MS e proteína bruta (PB. Quatro dietas foram elaboradas com diferentes granulometrias do bagaço de cana com diâmetro geométrico médio (DGM de 0,231, 0,506, 0,616 e 0,833 mm. O desempenho e os pesos do sistema digestivo cheio, sistema digestivo vazio, conteúdo do sistema digestivo, ceco cheio, ceco vazio e conteúdo cecal não foram afetados significativamente, entretanto o nitrogênio amoniacal do conteúdo cecal aumentou significativamente com o aumento da granulometria do bagaço de cana. Na avaliação da cecotrofia, foi observado efeito linear significativo da granulometria sobre a produção de cecotrofos e o teor de MS e PB ingerido por cecotrofia, porém sua composição química não foi afetada.Two experiments using New Zealand White x Californian rabbits were carried out with the objective of evaluating the effect of fiber source particle size on digestive traits of growing rabbit and the production, chemical composition and cecotrophes nutritive contribuition on dry matter (DM and crude protein (CP base. Four diets were prepared with different particle size of sugar cane bagasse with average geometric diameters of .231, .506, .616 and .833 mm. The productive performance and weight of the full and empty digestive tract, digestive tract content, full and empty cecum and cecum content were not affected, however the ammonia nitrogen percentage in the caecum content was significantly increased by increasing particle size of sugar cane bagasse. In cecotrophy evaluation, effects of particle size on cecotrophes production, DM and CP content ingested were observed, but the cecotrophes chemical

Electric distribution infrastructures for rural areas in developing countries

International Nuclear Information System (INIS)

Thirault, D.

2004-03-01

The main objective of the thesis was to study the architecture (network topology, mode of distribution, operation of energy sources, etc) distribution networks possible and adapted to the problem of rural electrification. Chapter I sets the context of rural electrification by detailing first the challenges of rural electrification for sustainable economic development and energy resources of these countries and the various existing network architectures. Specifications for the study is finally defined. Chapter II describes the design method developed to compare the costs of different architectures and choose the most suitable. Chapter III shows a method of sizing systems Decentralized Rural Electrification including generators, batteries and windmills. Chapter IV describes the results of a reliability study was carried out on different solutions. Chapter V describes the work done to analyze the operation of a production center consists of a generator and a wind turbine. (author)

Digestive tract

International Nuclear Information System (INIS)

Rocha, A.F.G. da

1976-01-01

Scintiscanning of salivary glands with (sup 99m)Tc is commented. The uses of triolein - and oleic acid labelled with 131 I, 125 I or 82 Br are discussed in the study of fat absorption, as well as 14 C and 191 Y. The use of 57 Co as a radiotracer in the intestinal absorption of vitamin B 12 is analysed. Orientation is given about 51 Cr - albumin clearance in the study of plasmatic protein loss by digestive tract. The radiotracers 131 I, 125 I and 51 Cr are pointed out in the investigation of immunoglobulins. Consideration is given to the quantification of digestive bleedings by the use of 51 Cr [pt

Temperature-phased anaerobic digestion of food waste: A comparison with single-stage digestions based on performance and energy balance.

Science.gov (United States)

Xiao, Benyi; Qin, Yu; Zhang, Wenzhe; Wu, Jing; Qiang, Hong; Liu, Junxin; Li, Yu-You

2018-02-01

The temperature-phased anaerobic digestion (TPAD) of food waste was studied for the purpose of comparing with single-stage mesophilic and thermophilic anaerobic digestion. The biogas and methane yields in the TPAD during the steady period were 0.759 ± 0.115 L/g added VS and 0.454 ± 0.201 L/g added VS, which were lower than those in the two single-stage anaerobic digestion. The improper sludge retention time may be the reason for the lower biogas and methane production in TPAD. The removal of volatile solids in the TPAD was 78.55 ± 4.59% and the lowest among the three anaerobic digestion processes. The reaction ratios of the four anaerobic digestion steps in the TPAD were all lower than those in the two single-stage anaerobic digestion. The energy conversion efficiency of the degraded substrate in the TPAD was similar with those in single-stage mesophilic and thermophilic anaerobic digestion systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

Determinants of the European Union rural population change in 2007-2010

Directory of Open Access Journals (Sweden)

Michał Dudek

2013-06-01

Full Text Available Natural change and migration are important determinants of the economy and environment. In the EU strategic documents the socio-economic developmental priorities have a territorial aspect, referring to all the regions of the member states. Achievement of the Union’s sustainable growth policy objectives could be limited due to unfavourable demographic trends in rural areas. The paper, using the Eurostat data and selected measures of population reproduction, describes the changes in number of rural inhabitants in 2007-2010 and their main determinants. In the analysed period the rural population size increased. However, contrary to the urban and intermediate regions, since 2009 as a result of a surplus number of deaths over births, in the rural areas the negative values of population increase were observed.

Obesity and Your Digestive Health

Science.gov (United States)

OBESITY AND YOUR DIGESTIVE HEALTH Do You Know Your GI Risks? A Patient Education Resource from the American College of Gastroenterology GI Specialists ... reduce the quality and longevity of your life. Digestive Disorders Associated with Obesity Esophagus Gallbladder Pancreas Colon ...

Protein digestibility and ammonia excretion in catfish Clarias gariepinus culture

Directory of Open Access Journals (Sweden)

Bambang Gunadi

2014-01-01

Full Text Available ABSTRACT A series of experiments was performed to analyze protein digestibility, ammonia excretion, and also heterothropic bacteria and phytoplankton dynamics in the catfish Clarias gariepinus culture. In the digestibility experiment, catfish with an individual initial size of 43.67±0.83 g were stocked into 120 L conical fiberglass tanks at a density of 20 fish per tank. Fish were fed on with commercial diet supplemented with Cr2O3 indicator at a concentration of 1%. In the ammonia excretion experiment, catfish with an individual size of 111.6±9.5 and 40.6±3.4 g, respectively,  were placed into a 10 L chamber filled with 8 L of water. Total ammonia nitrogen (TAN in the chambers were monitored every hour for six consecutive hours. In the bacteria and phytoplankton dynamics experiment, catfish were stocked in the 25 m2 concrete tanks which was divided into two compartments (catfish 10 m2, and heterotrof compartments 15 m2. Catfish with individual size of 42,5±0 g were stocked into the tanks at a density of 100 fish per tank. Water was recirculated from catfish compartments to heterotrophic compartments. Fish were fed with floating feed. Molasses as carbon source for heterotrophic bacteria was applied daily. The experiment was conducted for six weeks. The results showed that the protein digestibility was 61.97±7.24%. Larger fish (size of 111.6 g excreted ammonia at a rate of 0.008±0.003 mg TAN/g fish-weight/hour, which was lower than that of the smaller catfish (size of 40.6 g, i.e. 0.012±0.004 mg TAN/g fish-weight/hour. Keywords: protein digestibility, ammonia excretion, catfish  ABSTRAK Serangkaian penelitian telah dilakukan untuk menganalisis ketercernaan pakan dan protein, ekskresi amonia, serta dinamika bakteri dan fitoplankton pada budidaya ikan lele (Clarias gariepinus. Pada penelitian ketercernaan pakan, ikan lele berukuran 43,67±0,83 g/ekor dipelihara dalam bak fiberglas berbentuk corong berukuran 120 L dengan kepadatan 20

Aquaporins in Digestive System.

Science.gov (United States)

Zhu, Shuai; Ran, Jianhua; Yang, Baoxue; Mei, Zhechuan

2017-01-01

In this chapter, we mainly discuss the expression and function of aquaporins (AQPs ) expressed in digestive system . AQPs in gastrointestinal tract include four members of aquaporin subfamily: AQP1, AQP4, AQP5 and AQP8, and a member of aquaglyceroporin subfamily: AQP3. In the digestive glands, especially the liver, we discuss three members of aquaporin subfamily: AQP1, AQP5 and AQP8, a member of aquaglyceroporin subfamily: AQP9. AQP3 is involved in the diarrhea and inflammatory bowel disease; AQP5 is relevant to gastric carcinoma cell proliferation and migration; AQP9 plays considerable role in glycerol metabolism , urea transport and hepatocellular carcinoma. Further investigation is necessary for specific locations and functions of AQPs in digestive system.

Biogas generation potential by anaerobic digestion for sustainable energy development in India

International Nuclear Information System (INIS)

Rao, P. Venkateswara; Baral, Saroj S.; Dey, Ranjan; Mutnuri, Srikanth

2010-01-01

The potential of biogas generation from anaerobic digestion of different waste biomass in India has been studied. Renewable energy from biomass is one of the most efficient and effective options among the various other alternative sources of energy currently available. The anaerobic digestion of biomass requires less capital investment and per unit production cost as compared to other renewable energy sources such as hydro, solar and wind. Further, renewable energy from biomass is available as a domestic resource in the rural areas, which is not subject to world price fluctuations or the supply uncertainties as of imported and conventional fuels. In India, energy demand from various sectors is increased substantially and the energy supply is not in pace with the demand which resulted in a deficit of 11,436 MW which is equivalent to 12.6% of peak demand in 2006. The total installed capacity of bioenergy generation till 2007 from solid biomass and waste to energy is about 1227 MW against a potential of 25,700 MW. The bioenergy potential from municipal solid waste, crop residue and agricultural waste, wastewater sludge, animal manure, industrial waste which includes distilleries, dairy plants, pulp and paper, poultry, slaughter houses, sugar industries is estimated. The total potential of biogas from all the above sources excluding wastewater has been estimated to be 40,734 Mm 3 /year. (author)

Sensitivity and optimization of artificial digestion in the inspection of meat for Trichinella spiralis.

Science.gov (United States)

Li, Feng; Cui, Jing; Wang, Zhong-Quan; Jiang, Peng

2010-08-01

In many countries, the method of choice in inspecting meat for Trichinella spiralis infection is artificial digestion. We conducted a study of the sensitivity of the artificial digestion method recommended by the International Commission on Trichinellosis for detecting T. spiralis larvae in meat and of the effect of modifications of some procedures used in the method on its sensitivity. As part of this, we evaluated the effects on larval recovery of the vessels used for larval settling, sieve sizes, and temperatures at which larvae passed through the sieves, using larvae from T. spiralis-infected mice. We observed the effects on larval recovery of digestion duration and of modified artificial digestion by using 10-g samples of infected mouse muscle alone or mixed with uninfected pork. The percentages of larvae recovered with the respective use of separatory funnels and conical cylinders were 51.20% and 98.70%. The rates of recovery of T. spiralis larvae at 4 degrees C after passage through sieves of 425-microm mesh (No. 40), 250-microm mesh (No. 60), and 180-microm mesh (No. 80) were 98.42%, 90.59%, and 81.63%, which exceeded the 97.79%, 85.10%, and 61.12% rates of recovery of motile larvae at 40 degrees C and the 95.12%, 78.60%, and 44.16% rates of recovery of dead larvae at 90 degrees C. The larval recovery rate after digestion for 2 hours (96.18%) was greater than that after 0.5 hours (88.00%). We then examined a modified digestion method in which 10-g samples of pork mixed with 300 mL of digestive solution were digested for 2 hours at 43 degrees C followed by chilling of digest solution to 4 degrees C before passing it through a 425-microm mesh (No. 40) sieve and allowing it to settle in a 1-L conical cylinder. With this procedure, the modified method detected T. spiralis in samples of pork meat weighing 10 g and containing either 1 larva per gram or 0.1 larva per gram. Further validation of digestion method incorporating these modifications is required with

The anaerobic digestion process

Energy Technology Data Exchange (ETDEWEB)

Rivard, C.J. [National Renewable Energy Lab., Golden, CO (United States); Boone, D.R. [Oregon Graduate Inst., Portland, OR (United States)

1996-01-01

The microbial process of converting organic matter into methane and carbon dioxide is so complex that anaerobic digesters have long been treated as {open_quotes}black boxes.{close_quotes} Research into this process during the past few decades has gradually unraveled this complexity, but many questions remain. The major biochemical reactions for forming methane by methanogens are largely understood, and evolutionary studies indicate that these microbes are as different from bacteria as they are from plants and animals. In anaerobic digesters, methanogens are at the terminus of a metabolic web, in which the reactions of myriads of other microbes produce a very limited range of compounds - mainly acetate, hydrogen, and formate - on which the methanogens grow and from which they form methane. {open_quotes}Interspecies hydrogen-transfer{close_quotes} and {open_quotes}interspecies formate-transfer{close_quotes} are major mechanisms by which methanogens obtain their substrates and by which volatile fatty acids are degraded. Present understanding of these reactions and other complex interactions among the bacteria involved in anaerobic digestion is only now to the point where anaerobic digesters need no longer be treated as black boxes.

Gut microbiota and bacterial translocation in digestive surgery: the impact of probiotics.

Science.gov (United States)

Komatsu, Shunichiro; Yokoyama, Yukihiro; Nagino, Masato

2017-05-01

It is conceivable that manipulation of the gut microbiota could reduce the incidence or magnitude of surgical complications in digestive surgery. However, the evidence remains inconclusive, although much effort has been devoted to randomized controlled trials (RCTs) and meta-analyses on probiotics. Furthermore, the mechanism behind the protective effects of probiotics appears elusive, our understanding of probiotic actions being fragmentary. The objective of this review is to assess the clinical relevance of the perioperative use of probiotics in major digestive surgery, based on a comprehensive view of the gut microbiota, bacterial translocation (BT), and host defense system. The first part of this article describes the pathophysiological events associated with the gut microbiota. Results of RCTs for the perioperative use of probiotics in major digestive surgery are reviewed in the latter part. The development of the structural and functional barrier to protect against BT primarily results from the generally cooperative interactions between the host and resident microbiota. There is a large body of evidence indicating that probiotics, by enhancing beneficial interactions, reinforce the host defense system to limit BT. The perioperative use of probiotics in patients undergoing hepatobiliary and pancreatic surgery is a promising approach for the prevention of postoperative infectious complications, while the effectiveness in colorectal surgery remains controversial due to substantial heterogeneity among the RCTs with small sample populations. Further studies, such as multi-center RCTs with a larger sample size, are necessary to confirm the clinical relevance of probiotic agents in major digestive surgery.

On the effect of aqueous ammonia soaking pretreatment on batch and continuous anaerobic digestion of digested swine manure fibers

DEFF Research Database (Denmark)

Mirtsou Xanthopoulou, Chrysoula; Jurado, Esperanza; Skiadas, Ioannis

2012-01-01

, their economical profitable operation relies on increasing the methane yield from manure, and especially of its solid fraction which is not so easily degradable. Aqueous Ammonia Soaking (AAS) has been successfully applied on digested fibers separated from the effluent of a manure-fed, full-scale anaerobic digester......-pretreated digested manure fibers on the kinetics of anaerobic digestion process. It was found that AAS treatment had a profound effect mainly on the hydrolysis rate of particulate carbohydrates....

Digestible lysine levels in diets supplemented with ractopamine

Directory of Open Access Journals (Sweden)

Evelar de Oliveira Souza

2011-10-01

Full Text Available In order evaluate digestible lysine levels in diets supplemented with 20 ppm of ractopamine on the performance and carcass traits, 64 barrows with high genetic potential at finishing phase were allotted in a completely randomized block design with four digestible lysine levels (0.80, 0.90, 1.00, and 1.10%, eight replicates and two pigs per experimental unit. Initial body weight and pigs' kinship were used as criteria in the blocks formation. Diets were mainly composed of corn and soybean meal supplemented with minerals, vitamins and amino acids to meet pigs' nutritional requirements at the finishing phase, except for digestible lysine. No effect of digestible lysine levels was observed in animal performance. The digestible lysine intake increased linearly by increasing the levels of digestible lysine in the diets. Carcass traits were not influenced by the dietary levels of digestible lysine. The level of 0.80% of digestible lysine in diets supplemented with 20 ppm ractopamine meets the nutritional requirements of castrated male pigs during the finishing phase.

Testing low cost anaerobic digestion (AD) systems

Science.gov (United States)

To evaluate the potential for low technology and low cost digesters for small dairies, BARC and researchers from the University of Maryland installed six modified Taiwanese-model field-scale (FS) digesters near the original dairy manure digester. The FS units receive the same post-separated liquid ...

The harmonized INFOGEST in vitro digestion method

NARCIS (Netherlands)

Egger, Lotti; Ménard, Olivia; Delgado-Andrade, Cristina; Alvito, Paula; Assunção, Ricardo; Balance, Simon; Barberá, Reyes; Brodkorb, Andre; Cattenoz, Thomas; Clemente, Alfonso; Comi, Irene; Dupont, Didier; Garcia-Llatas, Guadalupe; Lagarda, María Jesús; Feunteun, Le Steven; Janssen Duijghuijsen, Lonneke; Karakaya, Sibel; Lesmes, Uri; Mackie, Alan R.; Martins, Carla; Meynier, Anne; Miralles, Beatriz; Murray, B.S.; Pihlanto, Anne; Picariello, Gianluca; Santos, C.N.; Simsek, Sebnem; Recio, Isidra; Rigby, Neil; Rioux, Laurie Eve; Stoffers, Helena; Tavares, Ana; Tavares, Lucelia; Turgeon, Sylvie; Ulleberg, E.K.; Vegarud, G.E.; Vergères, Guy; Portmann, Reto

2016-01-01

Within the active field of in vitro digestion in food research, the COST Action INFOGEST aimed to harmonize in vitro protocols simulating human digestion on the basis of physiologically inferred conditions. A harmonized static in vitro digestion (IVD) method was recently published as a primary

Evaluation of the antioxidant activity in food model system of fish peptides released during simulated gastrointestinal digestion

DEFF Research Database (Denmark)

Nieva-Echevarria, B.; Jacobsen, Charlotte; García Moreno, Pedro Jesús

In the last decade, increasing evidences of the occurrence of lipid oxidation during digestion have been reported, in either in vivo or in vitro studies (1,2,3). As a result, the nutritional quality and safety of foodstuffs could be affected by the decrease of certain lipidic compounds of interest...... in the gastrointestinal tract. In fact, several studies have reported antioxidant activity of fish protein hydrolysates, coming from fish industry waste by-products (3,4). Thus, the potential release of peptides showing antioxidant properties during fish digestion cannot be ruled out. In order to shed light...... on these aspects, in vitro digestates of European sea bass were submitted to ultrafiltration using membranes with different cut off size. Afterwards, the potential antioxidant activity of the peptide fractions obtained was evaluated by comparing the oxidative stability of fish oil-in-water emulsions (5...

Acid digestion of organic materials

International Nuclear Information System (INIS)

Capp, P.D.

1988-01-01

To overcome the high temperatures involved in straight incineration of organic waste and the difficulty of extracting actinides from the ash various research establishments throughout the world, including Winfrith and Harwell in the UK, have carried out studies on an alternative chemical combustion method known as acid digestion. The basis of the technique is to digest the waste in concentrated sulphuric acid containing a few percent of nitric acid at a temperature of about 250 0 C. Acid digestion residues consist mainly of non-refractory inorganic sulphates and oxides from which any actinide materials can easily be extracted. (author)

Factors Influencing the Consumption of Pulses in Rural and Urban ...

African Journals Online (AJOL)

Model results revealed that household sizes and education levels of the decision makers residing ... Key words: Pulses consumption, urban and rural areas, Tanzania and double hurdle model ...... Food and Agriculture Organization Statistics.

Cow, sheep and llama manure at psychrophilic anaerobic co-digestion with low cost tubular digesters in cold climate and high altitude.

Science.gov (United States)

Martí-Herrero, J; Alvarez, R; Cespedes, R; Rojas, M R; Conde, V; Aliaga, L; Balboa, M; Danov, S

2015-04-01

The aim of this research is to evaluate the co-digestion of cow and llama manure combined with sheep manure, in psychrophilic conditions and real field low cost tubular digesters adapted to cold climate. Four digesters were monitored in cold climate conditions; one fed with cow manure, a second one with llama manure, the third one with co-digestion of cow-sheep manure and the fourth one was fed with llama-sheep manure. The slurry had a mean temperature of 16.6 °C, the organic load rate was 0.44 kgvs m(-3) d(-1) and the hydraulic retention time was 80 days. After one hundred days biogas production was stable, as was the methane content and the pH of the effluent. The co-digestion of cow-sheep manure results in a biogas production increase of 100% compared to the mono-digestion of cow manure, while co-digestion of llama-sheep manure results in a decrease of 50% in biogas production with respect to mono-digestion of llama manure. Copyright © 2015 Elsevier Ltd. All rights reserved.

Modeling the Dynamic Digestive System Microbiome†

OpenAIRE

Estes, Anne M.

2015-01-01

“Modeling the Dynamic Digestive System Microbiome” is a hands-on activity designed to demonstrate the dynamics of microbiome ecology using dried pasta and beans to model disturbance events in the human digestive system microbiome. This exercise demonstrates how microbiome diversity is influenced by: 1) niche availability and habitat space and 2) a major disturbance event, such as antibiotic use. Students use a pictorial key to examine prepared models of digestive system microbiomes to determi...

Substance Use Prevention among At-Risk Rural Youth: Piloting the Social Ecological "One Life" Program

Science.gov (United States)

Williams, Ronald D., Jr.; Barnes, Jeremy T.; Holman, Thomas; Hunt, Barry P.

2014-01-01

Substance use among youth is a significant health concern in the rural United States, particularly among at-risk students. While evidence-based programs are available, literature suggests that an underdeveloped rural health prevention workforce often limits the adoption of such programs. Additionally, population-size restrictions of national…

Rural Medicine Realities: The Impact of Immersion on Urban-Based Medical Students.

Science.gov (United States)

Crump, Allison M; Jeter, Karie; Mullins, Samantha; Shadoan, Amber; Ziegler, Craig; Crump, William J

2017-05-02

The purpose of our study was to determine what effect a rural-based 8-week surgical clerkship during the third year of medical school in a rural setting has on students' opinions about rural living and practice. Thirty-three third-year medical students completed a rural health opinion survey at the beginning and end of their 8-week rural rotation and a survey measuring their interest in rural practice after the rotation. The setting was a rural hospital with an average acute care census of 100 that is a regional referral center for 5 rural counties. Urban campus-based students had a statistically significant positive change in opinions about rural comfortable living, availability of quality services, community support, and medical resources. The urban campus-based students also showed a significantly increased interest in small town practice after the rotation. Our hypothesis that urban-based students would report an increased level of rural community support at the end of the rotation was confirmed. These urban-based students also reported positive opinions about rural living and practice. The students primarily based at the urban campus also showed a statistically significant more positive attitude toward pursuing a career in a small town after the 8-week experience. This suggests that brief rural immersion experiences may make the larger student pool at an urban campus available to address rural workforce challenges. Future studies at multiple rural sites with a larger sample size are needed to confirm this possibility. © 2017 National Rural Health Association.

The effects of gastric digestion on codfish allergenicity

DEFF Research Database (Denmark)

Untersmayr, Eva; Poulsen, Lars K.; Platzer, Michael H

2005-01-01

In a recent murine study, we showed that impaired gastric digestion supports the induction of fish allergy by protecting the digestion-sensitive major allergen parvalbumin and thus enhancing its sensitizing properties.......In a recent murine study, we showed that impaired gastric digestion supports the induction of fish allergy by protecting the digestion-sensitive major allergen parvalbumin and thus enhancing its sensitizing properties....

Narrowing the size distribution of CdTe nanocrystals using digestive ...

Indian Academy of Sciences (India)

2015-06-02

Jun 2, 2015 ... Several synthetic methods have been developed to get monodis- persed nanoparticles by carefully controlling the amount of precursor, capping agent, rate of the reaction and the reaction temperature. Size-selective precipitation, a post-synthetic method, is used to achieve monodispersed nanoparticles but ...

Amino acids digestibility of pelleted microparticle protein of fish meal and soybean meal in broiler chickens

Directory of Open Access Journals (Sweden)

N. Suthama

2018-05-01

Full Text Available Commom protein sources for poultry, fish meal and soybean meal, were ground to obtain reduced particle size. The particle was then dissolved in distilled water (1 : 4 w/v, and added with 2 mL virgin coconut oil for every 500 mL solution prior to ultrasound transducer (ultrasonic bath treatment to obtain protein microparticle. Reducing particle size is one possible way to increase protein utilization.180 birds were used for forced feeding and 10 other birds were plotted for endogenous correction, when they were one month and a half old. Microparticle protein of both ingredients were tested separately in either mash or pelleted forms and compared to intact protein. Completely randomized design with 3 treatments (intact, mash, and pellet and 6 replications (10 bidrs each was arranged for the respective ingredient. Protein and essential amino acid digestibilities, and calcium retention were the parameters measured. Analysis of variance continued to Duncan test were applied to statistically evaluate the data. Pelleted microparticle protein of fish meal and soybean meal, respectively, resulted in significantly (P<0.05 highest protein and amino acids digestibilities, and Ca retention although lower disgestibility of fewer amino acids was found in mash form. In conclusion, pelleted form of microparticle protein of either fish meal or soybean meal improve protein and mostly amino acids digestibilities, and calcium retention in broiler.

A HYBRID APPROACH FOR RURAL FEEDER DESIGN

Directory of Open Access Journals (Sweden)

DAMANJEET KAUR

2012-08-01

Full Text Available In this paper, a population based approach for conductor size selection in rural radial distribution system is presented. The proposed hybrid approach implies a particle swarm optimization (PSO approach in combination with mutant property of differential evolution (DE for conductor size selection in radial distribution system. The conductor size for each feeder segment is selected such that the total cost of capital investment and capitalized cost of energy losses is minimized while constraints of voltage at each node and current carrying capacity of conductor is within the limits. The applicability and effectiveness of the proposed method is demonstrated with the help of 32-node test system.

Preliminary experimental results of Sewage Sludge (SS) Co-digestion with Palm Oil Mill Effluent (POME) for Enhanced Biogas Production in Laboratory Scale Anaerobic Digester

International Nuclear Information System (INIS)

Sivasankari, R; Kumaran, P; Normanbhay, Saifuddin; Shamsuddin, Abd Halim

2013-01-01

An investigation on the feasibility of co-digesting Sewage Sludge with Palm Oil Mill Effluent for enhancing the biogas production and the corresponding effect of the co-digestion substrate ratio on the biogas production has been evaluated. Anaerobic co-digestion of POME with SS was performed at ratios of 100:0, 70:30, 60:40 and 0:100 to find the optimum blend required for enhanced waste digestion and biogas production. Single stage batch digestion was carried out for 12 days in a laboratory scale anaerobic digester. Co-digestion of sludge's at the 70:30 proportion resulted in optimal COD and C: N ratio which subsequently recorded the highest performance with regards to biogas production at 28.1 L's compared to the 1.98 L's of biogas produced from digestion of SS alone. From the results obtained, it is evident that co-digestion of POME and SS is an attractive option to be explored for enhancement of biogas production in anaerobic digesters.

Deregulated HOXB7 expression predicts poor prognosis of patients with malignancies of digestive system.

Science.gov (United States)

Liu, Fang-Teng; Chen, Han-Min; Xiong, Ying; Zhu, Zheng-Ming

2017-07-26

Numerous studies have investigated the relationship between deregulated HOXB7 expression with the clinical outcome in patients with digestive stem cancers, HOXB7 has showed negative impacts but with varying levels. We aimed to comprehensively evaluate the prediction and prognostic value of HOXB7 in digestive stem cancers. Electronic databases updated to December 1, 2016 were retrieved to collect relevant eligible studies to quantitatively explore the potential roles of HOXB7 as a prognostic indicator in digestive system cancers. A total of 9 studies (n = 1298 patients) was included in this synthetical meta-analysis. The pooled hazard ratios suggested that high expression of HOXB7 protein was associated with poor prognosis of OS in patients with digestive system cancers (HR = 1.97, 95% CI: 1.65-2.28, p= 0.000), and HOXB7 protein could act as an independent prognostic factor for predicting OS of patients with digestive system cancers (HR: 2.02, 95% CI: 1.69-2.36, p = 0.000). Statistical significance was also observed in subgroup meta-analysis based on the cancer type, histology type, country, sample size and publication date. Furthermore, we examined the correlations between HOXB7 protein and clinicopathological features. It showed that altered expression of HOXB7 protein was correlated with tumor invasion (p = 0.000), lymph node status (p = 0.000), distant metastasis (p = 0.001) and TNM stage (p = 0.000). However, the expression of HOXB7 protein was not associated with age (p = 0.64), gender (p = 0.40) or levels of differentiation (p = 0.19). High expression of HOXB7 protein was associated with poor prognosis of patients with digestive system cancers, as well as clinicopathologic characteristics, including the tumor invasion, lymph node status, distant metastasis and TNM stage. The expression of HOXB7 protein was not associated with age, gender or levels of differentiation. HOXB7 protein expression level in tumor tissue might serve as a novel prognostic marker for

Waste volume reduction by acid digestion

International Nuclear Information System (INIS)

Lerch, R.E.; Divine, J.R.

1975-06-01

Acid digestion is a process being developed at the Hanford Engineering Development Laboratory (HEDL) in Richland, Washington, to reduce the volume of alpha-contaminated combustible waste by converting it into a non-combustible residue. Typical waste materials such as polyvinylchloride (PVC), polyethylene, paper and other cellulosic materials, ion exchange resin, all types of rubber, etc., are digested in hot (230 0 C--270 0 C) concentrated sulfuric acid containing nitric acid oxidant to form inert residues generally having less than four percent of their original volume and less than twenty-five percent of their original mass. The process is currently being tested using non-radioactive waste in an Acid Digestion Test Unit (ADTU) with all glass equipment. Engineering tests to date have shown acid digestion to be a potentially attractive method for treating combustible waste materials. Based on results of the engineering tests, an acid digestion pilot unit capable of treating radioactive wastes is being designed and constructed. Design capacity of the pilot unit for radioactive waste will be 100 kg of waste per day. (U.S.)

A contemporary decennial global sample of changing agricultural field sizes

Science.gov (United States)

White, E.; Roy, D. P.

2011-12-01

In the last several hundred years agriculture has caused significant human induced Land Cover Land Use Change (LCLUC) with dramatic cropland expansion and a marked increase in agricultural productivity. The size of agricultural fields is a fundamental description of rural landscapes and provides an insight into the drivers of rural LCLUC. Increasing field sizes cause a subsequent decrease in the number of fields and therefore decreased landscape spatial complexity with impacts on biodiversity, habitat, soil erosion, plant-pollinator interactions, diffusion of disease pathogens and pests, and loss or degradation in buffers to nutrient, herbicide and pesticide flows. In this study, globally distributed locations with significant contemporary field size change were selected guided by a global map of agricultural yield and literature review and were selected to be representative of different driving forces of field size change (associated with technological innovation, socio-economic conditions, government policy, historic patterns of land cover land use, and environmental setting). Seasonal Landsat data acquired on a decadal basis (for 1980, 1990, 2000 and 2010) were used to extract field boundaries and the temporal changes in field size quantified and their causes discussed.

Bacterial population of piggery-waste anaerobic digesters

Energy Technology Data Exchange (ETDEWEB)

Hobson, P N; Shaw, B G

1974-08-01

A survey was made of the anaerobic and facultatively anaerobic bacteria present in piggery waste, digesting piggery waste and domestic anaerobic sludge used to start a piggery waste digester. An influence of the input waste was shown in that streptococci, the predominant facultatively anaerobic bacteria in the piggery waste, were the predominant bacteria in the digesting waste, and they replaced Entrobacter, predominant in the domestic sludge, when a piggery waste digestion had been established from this latter material. Cellulolytic or methanogenic bacteria could not be detected in the piggery waste but populations of these, and other hydrolytic bacteria, became established at different times during the build-up of digestion by gradual addition of piggery waste to water. The bacteria concerned in degradation of the waste constituents were all anaerobes. Production of methane from H/sub 2//CO/sub 2/, formate and butyrate could be detected in mixed cultures from dilutions of digester contents, but the only methanogenic bacterium that could be isolated in pure culture was Methanobacterium formicicum, which uses H/sub 2//CO/sub 2/ or formate only.

Rirang Uranium Ore Processing System Design: Agitated Digester

International Nuclear Information System (INIS)

Erni, R.A.; Susilaningtyas

1996-01-01

A closed tank digester equipped with a pitched blades turbine agitator has been designed to facilities Rirang uranium ore dissolution using concentrated sulphuric acid at high temperature. The digester was designed to accommodate the digestion of 6 kg of-65 mesh ore at 200 o C, acid resistant material (SS-3 16). It has the dimension of 33 cm high, 22 cm diameter, and elliptical bottom and height of 4 cm. Moreover, the dimension of the 4 blades agitator is as follows: 8 cm long, 1,6 cm blades width. The distance between the blades and digester required 0, 007 Hp for a 500 rpm agitation speed and + 24. 103 kcal energy equipment for heating. Digestion experiment using the agitated digester yielded data that are in good agreement with laboratory scale experiment

Restrictions and Countermeasures of Rural Vocational Education in Urban-rural Integration

Institute of Scientific and Technical Information of China (English)

2012-01-01

Developing rural vocational education is of great significance to urban-rural integration: developing rural vocational education is helpful to cultivating new farmers for construction of new socialist countryside,favorable to improving farmers’ ability of finding jobs and starting undertaking, and beneficial to transfer of rural surplus labor and acceleration of urbanization. Restrictions on development rural vocational education mainly include: low value cognition of society and social assessment of rural vocational education; out of balance of cost and expected return of rural vocational education; the quality of supply of rural vocational education failure to satisfy demand of socio-economic development; imperfect rural vocational education system. In view of these,following countermeasures and suggestions are put forward: strengthen propaganda and guidance to build environment of public opinion for rural vocational education; push forward rural vocational compulsory education system to lay social foundation for rural vocational education; reinforce policy support to assist in building rural vocational education system; improve education system to build overall framework of rural vocational education; perfect laws and regulations to establish system and norm for development of rural vocational education.

Managerial Strategies for the Conservation of Rurality in Rural Tourism

Directory of Open Access Journals (Sweden)

Cornelia Petroman

2010-10-01

Full Text Available If we admit that rurality designates small densities, open areas, small settlements below 1,000 inhabitants, and land reserved mainly to agricultural and forestry practices, and as natural area, if we admit that society tends to be traditional and that government al policies tend to conserve rather than to make rapid or radical changes, then we should admit that rural tourism should be an activity generating new incomes in the area. Rurality also means preserving a continuum in the approach of different types of areas with different characteristics, a concept that can also be of use in the identification of activities specific to rural tourism. Be they activities specific to the rural environment or activities common to the rural area, they need to aim at the conservation of rurality as a main tourism resource. Managerial strategies in rural tourism contribute effectively to rural development, provided they are sustainable and that rural tourism be not the only solution for rural development.

Apparent seed digestibility and germination of seeds after passage through the digestive system of northern bobwhite

Science.gov (United States)

Limited information is available regarding the digestibility or germination of seed after the passage through the digestive system of northern bobwhites (Colinus virginianus), especially of plants associated with the sand sagebrush (Artemisia filifolia)-mixed prairie community. Thus, our objectives...

Effect of Different Heat Treatments on In Vitro Digestion of Egg White Proteins and Identification of Bioactive Peptides in Digested Products.

Science.gov (United States)

Wang, Xuefen; Qiu, Ning; Liu, Yaping

2018-04-01

Chicken eggs are ingested by people after a series of processes, but to date, only a few studies have explored the nutrient variations caused by different heat treatments. In this work, the impacts of different heat treatments (4, 56, 65, and 100 °C on the in vitro digestibility of egg white proteins were investigated by hydrolysis with pepsin or pepsin + pancreatin to simulate human gastrointestinal digestion, and the digested products were identified using Nano-LC-ESI-MS/MS. Egg white proteins treated at 65 °C had the highest in vitro pepsin digestibility value whereas the pepsin + pancreatin digestibility increased significantly (P cooking temperature was raised. The molecular weight distribution of the digested products indicated that, when compared to pepsin-treated samples, pepsin + pancreatin-treated samples contained more low-molecular-weight peptides (m/z egg white digested products, especially in samples treated at 4 and 100 °C. These findings may facilitate a better understanding of nutritive values of egg white proteins and their digested products under different cooking temperatures, such as antibacterial and antioxidant peptides identified in the digestion samples treated, respectively at 4 and 100 °C. This study also provided information for improving the applications of eggs in the food industry as well as a theoretical basis for egg consumption. © 2018 Institute of Food Technologists®.

The rural villages electrification with a hybrid photovoltaic

International Nuclear Information System (INIS)

Kocev, Kiril; Dimitrov, Dimitar; Tugjarov, Gjorgji

2002-01-01

Depending on a daily load demand, distance from the utility grid and the available solar energy, the rural villages electrification with a hybrid photovoltaic (PV) system can be a cheaper solution than the classic electrification, by connecting them to the utility grid. Besides PV generator, the considered hybrid system is consisted of a battery and a diesel genset. For the concrete case - rural village with estimated daily load demand of 15.5 kWh/day, with the computer program PVFORM, which is modified for such hybrid system, were simulated a few hundreds PV systems, with different sizes of the PV generator and of the battery capacity. Analyzing the obtained results, it can be foreseen the influence of the component size on the system functionality. From the mass of possible system combinations, it is chosen one that has 42 % lower initial investment, than the initial investment for connection of the village to the utility grid. (Original)

Academic Life at the Franchise: Faculty Culture in a Rural Two-Year Branch Campus.

Science.gov (United States)

Wolfe, John R.; Strange, C. Carney

2003-01-01

This case study of faculty culture focused on the dynamics of a small, rural, two-year branch campus of a large state university. It reports descriptive themes concerning the isolation and rural location of the campus, its diminutive size, faculty role perspectives, and factors related to faculty role implementation. It provides a portrait of this…

Relationship between physiological measurements (SFG -scope for growth-) and the functionality of the digestive gland in Mytilus galloprovincialis.

Science.gov (United States)

Albentosa, Marina; Sánchez-Hernández, Miriam; Campillo, Juan Antonio; Moyano, Francisco Javier

2012-11-01

The present study was aimed to establish the relationship between the functionality of the digestive gland and physiological rates including SFG (scope for growth) in wild mussels, Mytilus galloprovincilis. The experimental set-up consisted in the evaluation of changes in the morphology of the gland, as well as in the activity of some key digestive enzymes (amylase, laminarinase, cellulase and protease) within a broad range of SFG obtained through manipulation of food ration. The higher SFG values were correlated to an increase in both the size of the digestive gland and the activities of enzymes when expressed in relation to individual. In contrast, no clear relations were observed when the activity of enzymes was expressed in relation to soluble protein, with the exception to amylase. The higher protease activities measured in mussels showing lower SFG may reflect an initial stage of catabolic processes intended to compensate the energy deficit produced by food restriction. The potential use of parameters measured in digestive glands in studies of marine pollution was discussed. Copyright © 2012 Elsevier Inc. All rights reserved.

Acid digestion of combustible radioactive wastes

International Nuclear Information System (INIS)

Allen, C.R.; Lerch, R.E.; Crippen, M.D.; Cowan, R.G.

1982-03-01

The following conclusions resulted from operation of Radioactive Acid Digestion Test Unit (RADTU) for processing transuranic waste: (1) the acid digestion process can be safely and efficiently operated for radioactive waste treatment.; (2) in transuranic waste treatment, there was no detectable radionuclide carryover into the exhaust off-gas. The plutonium decontamination factor (DF) between the digester and the second off-gas tower was >1.5 x 10 6 and the overall DF from the digester to the off-gas stack was >1 x 10 8 ; (3) plutonium can be easily leached from undried digestion residue with dilute nitric acid (>99% recovery). Leachability is significantly reduced if the residue is dried (>450 0 stack temp.) prior to leaching; (4) sulfuric acid recovery and recycle in the process is 100%; (5) nitric acid recovery is typically 35% to 40%. Losses are due to the formation of free nitrogen (N 2 ) during digestion, reaction with chlorides in waste (NO 2 stack was > 1.5 x 10 6 andl), and other process losses; (6) noncombustible components comprised approximately 6% by volume of glovebox waste and contained 18% of the plutonium; (7) the acid digestion process can effectively handle a wide variety of waste forms. Some design changes are desirable in the head end to reduce manual labor, particularly if large quantities of specific waste forms will be processed; (8) with the exception of residue removal and drying equipment, all systems performed satisfactorily and only minor design and equipment changes would be recommended to improve performance; and(9) the RADTU program met all of its planned primary objectives and all but one of additional secondary objectives

Digestive diseases

Science.gov (United States)

... prolapse Esophagus problems, such as stricture (narrowing) and achalasia Liver problems, such as hepatitis B or hepatitis ... has received extra training in the diagnosis and treatment of the digestive disorders. Other health care providers ...

Recruiting and retaining high-quality teachers in rural areas.

Science.gov (United States)

Monk, David H

2007-01-01

In examining recruitment and retention of teachers in rural areas, David Monk begins by noting the numerous possible characteristics of rural communities--small size, sparse settlement, distance from population concentrations, and an economic reliance on agricultural industries that are increasingly using seasonal and immigrant workers to minimize labor costs. Many, though not all, rural areas, he says, are seriously impoverished. Classes in rural schools are relatively small, and teachers tend to report satisfaction with their work environments and relatively few problems with discipline. But teacher turnover is often high, and hiring can be difficult. Monk observes that rural schools have a below-average share of highly trained teachers. Compensation in rural schools tends to be low, perhaps because of a lower fiscal capacity in rural areas, thus complicating efforts to attract and retain teachers. Several student characteristics, including relatively large shares of students with special needs and with limited English skills and lower shares of students attending college, can also make it difficult to recruit and retain high-quality teachers. Other challenges include meeting the needs of highly mobile children of low-income migrant farm workers. With respect to public policy, Monk asserts a need to focus on a subcategory of what might be called hard-to-staff rural schools rather than to develop a blanket set of policies for all rural schools. In particular, he recommends a focus on such indicators as low teacher qualifications, teaching in fields far removed from the area of training, difficulty in hiring, high turnover, a lack of diversity among teachers in the school, and the presence of migrant farm workers' children. Successful efforts to stimulate economic growth in these areas would be highly beneficial. He also calls attention to the potential for modern telecommunication and computing technologies to offset some of the drawbacks associated with teaching

Effect of volatile and acid accumulation in dung digestion

Energy Technology Data Exchange (ETDEWEB)

Rajagopal, G; Pathak, B N

1966-01-01

In continuation of laboratory experiments on the anaerobic digestion of cow dung experiments were carried out to determine the limiting concentrations of volatile acids and to investigate methods of regenerating digestion after failure. Volatile acids were increased by adding acetic acid to digesting dung slurry; digestion failed completely when volatile-acid concentration was 6194 mg per litre, at pH 4.4. Attempts were made to regenerate digestion by adding lime, after dilution with water, but although over a period the volatile-acid content was reduced from 5650 to 3730 mg per litre, and the pH value rose on average from 4.5 to 6.3, gas production remained at a low value until additional digested slurry was introduced, leading to resumption of normal digestion.

Multi criteria analysis for sustainability assessments of electricity generation systems in a rural community in South Africa

Energy Technology Data Exchange (ETDEWEB)

Amigun, B.; Mehlwana, M. [Council for Scientific and Industrial Research, Pretoria (South Africa). Sustainable Energy Futures, Natural Resources and the Environment; Musango, J.K. [Department of Energy (DoE), Pretoria (South Africa); Brent, A.C. [Stellenbosch Univ. (South Africa). Centre for Renewable and Sustainable Energy Studies

2011-07-01

One of the key challenges of the energy policy in South Africa is to ensure that rural areas have access to electricity. This is reflected in the key energy policy documents (the 1998 Energy White Paper and the 2002 Renewable Energy White Paper). Both these documents identified renewable energy resources as immediate alternatives to grid electricity in especially remote rural communities that are characterised by low population densities. Centralised energy generation and transmission is very costly and inefficient in these areas due to greater transmission and distribution losses. While the cost of electricity in South Africa is relatively cheaper, it is not accessible for many rural households. There are still over two million households in rural areas without access to electricity. This paper presents a multi-criteria decision analysis (MCDA) using the Analytical Hierarchy Process (AHP) technique to compare various electricity technologies (mainly renewables) in a specific rural community of South Africa using social, economic, environment and technical indicators. These technologies were than ranked against each indicator assuming that the high-level criteria have equal importance for sustainable development. It is demonstrated that energy from wind is the most sustainable, followed by photovoltaic, anaerobic digestion (biogas) and then gasification. A sensitivity analysis was also performed to verify the stability of the priority ranking. The outcome of this study will specifically assist energy planners and decision-makers to choose the best alternative from a range of technology alternatives in a milieu of conflicting and competing criteria. (orig.)

Influence of UK energy policy on the deployment of anaerobic digestion

Energy Technology Data Exchange (ETDEWEB)

Zglobisz, Natalia; Castillo-Castillo, Arturo [Centre for Environmental Policy, Imperial College London, Exhibition Road, London SW7 2AZ (United Kingdom); Grimes, Sue [Department of Civil and Environmental Engineering, Imperial College London, Exhibition Road, London SW7 2AZ (United Kingdom); Jones, Peter [Greater London Authority, Ivy House, North Kilworth, Leicestershire LE17 6HG (United Kingdom)

2010-10-15

Anaerobic digestion (AD) has the potential to contribute to greenhouse gas emissions reductions, improve energy security, increase generation of decentralised renewable electrical and thermal energy, produce low-impact fertiliser and enhance adherence to the principles of proximity as well as self-sufficiency in waste treatment, in energy generation and in resource use. Financial viability is scrutinised investigating optimal logistic pre-conditions such as catchment area or plant size. Given that a breakthrough in deployment does not only depend on technical aspects, the relative importance and magnitude of the necessary incentives is discussed. The influence of policy instruments is studied by devising different incentive scenarios for the United Kingdom. Substantial and predictable rewards for renewable electricity and heat are essential to harness the full potential of AD in addition to the current emphasis on landfill tax. A possible configuration of energy supply companies as a crucial vehicle to bring anaerobic digestion to market is highlighted. (author)

Influence of UK energy policy on the deployment of anaerobic digestion

International Nuclear Information System (INIS)

Zglobisz, Natalia; Castillo-Castillo, Arturo; Grimes, Sue; Jones, Peter

2010-01-01

Anaerobic digestion (AD) has the potential to contribute to greenhouse gas emissions reductions, improve energy security, increase generation of decentralised renewable electrical and thermal energy, produce low-impact fertiliser and enhance adherence to the principles of proximity as well as self-sufficiency in waste treatment, in energy generation and in resource use. Financial viability is scrutinised investigating optimal logistic pre-conditions such as catchment area or plant size. Given that a breakthrough in deployment does not only depend on technical aspects, the relative importance and magnitude of the necessary incentives is discussed. The influence of policy instruments is studied by devising different incentive scenarios for the United Kingdom. Substantial and predictable rewards for renewable electricity and heat are essential to harness the full potential of AD in addition to the current emphasis on landfill tax. A possible configuration of energy supply companies as a crucial vehicle to bring anaerobic digestion to market is highlighted.

Evaluation of anaerobic digestion processes for short sludge-age waste activated sludge combined with anammox treatment of digestate liquor.

Science.gov (United States)

Ge, Huoqing; Batstone, Damien; Keller, Jurg

2016-01-01

The need to reduce energy input and enhance energy recovery from wastewater is driving renewed interest in high-rate activated sludge treatment (i.e. short hydraulic and solids retention times (HRT and SRT, respectively)). This process generates short SRT activated sludge stream, which should be highly degradable. However, the evaluation of anaerobic digestion of short SRT sludge has been limited. This paper assesses anaerobic digestion of short SRT sludge digestion derived from meat processing wastewater under thermophilic and mesophilic conditions. The thermophilic digestion system (55°C) achieved 60 and 68% volatile solids destruction at 8 day and 10 day HRT, respectively, compared with 50% in the mesophilic digestion system (35°C, 10 day HRT). The digestion effluents from the thermophilic (8-10 day HRT) and mesophilic systems were stable, as assessed by residual methane potentials. The ammonia rich sludge dewatering liquor was effectively treated by a batch anammox process, which exhibited comparable nitrogen removal rate as the tests using a control synthetic ammonia solution, indicating that the dewatering liquor did not have inhibiting/toxic effects on the anammox activity.

Prospects of Anaerobic Digestion Technology in China

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

As the world's largest developing country, China must face the problem of managing municipal solid waste, and the challenge of organic waste disposal is even more serious. Considering the characteristics of traditional waste disposal technologies and the subsequent secondary pollution, anaerobic digestion has various advantages such as reduction in the land needed for disposal and preservation of environmental quality. In light of the energy crisis, this paper focuses on the potential production of biogas from biowaste through anaerobic digestion processes, the problems incurred by the waste collection system, and the efficiency of the anaerobic digestion process. Use of biogas in a combined heat and power cogeneration system is also discussed. Finally, the advantages of anaerobic digestion technology for the Chinese market are summarized. The anaerobic digestion is suggested to be a promising treating technology for the organic wastes in China.

Within-species digestive tract flexibility in rufous-collared sparrows and the climatic variability hypothesis.

Science.gov (United States)

Maldonado, Karin; Bozinovic, Francisco; Rojas, José M; Sabat, Pablo

2011-01-01

The climatic variability hypothesis (CVH) states that species are geographically more widespread at higher latitudes because individuals have a broader range of physiological tolerance or phenotypic flexibility as latitude and climatic variability increase. However, it remains unclear to what extent climatic variability or latitude, acting on the phenotype, account for any observed geographical gradient in mean range size. In this study, we analyzed the physiological flexibility within the CVH framework by using an intraspecific population experimental approach. We tested for a positive relationship between digestive-tract flexibility (i.e., morphology and enzyme activities) and latitude and climatic and natural diet variability in populations of rufous-collared sparrows (Zonotrichia capensis) captured in desert (27°S), Mediterranean (33°S), and cold-temperate (41°S) sites in Chile. In accordance with the CVH, we observed a positive relationship between the magnitude of digestive-tract flexibility and environmental variability but not latitude. The greatest digestive flexibility was observed in birds at middle latitudes, which experience the most environmental variability (a Mediterranean climate), whereas individuals from the most stable climates (desert and cold-temperate) exhibited little or no digestive-tract flexibility in response to experimental diets. Our findings support the idea that latitudinal gradients in geographical ranges may be strongly affected by the action of regional features, which makes it difficult to find general patterns in the distribution of species.

Creation of a mobile rural workforce following undergraduate longitudinal rural immersion.

Science.gov (United States)

Playford, Denese E; Ng, Wen Qi; Burkitt, Tessa

2016-05-01

This study followed the workforce choices of 10-years of graduates from a longitudinal rural immersion programme, which involved living for one academic year in a rural location as a medical student. The Rural Clinical School of Western Australia is a whole-of-state Rural Clinical School partnership involving two medical schools and fourteen rural/remote towns. For this longitudinal cohort study, all consenting graduates were contacted annually after graduation, with the outcome measure being rural work location (defined by the Australian Standard Geographical Classification -Remoteness Area) of any duration. There were 417 consenting graduates. Between 16 and 50% of contacted alumni worked rurally for a period of each post-graduate year. Aggregated over time, the majority took up to 30% of their postgraduate training rurally. There was considerable movement in and out of rural work. About 17% of contacted and practicing graduates were working full time rurally at the 2013 contact point. The majority remained in their state of training. The majority identified with GP and other rural-related colleges, and College-affiliation predicted amount of rural training time. Entry into rural work was equivalent for urban-origin and rural origin alumni, suggesting one year of RCS is sufficient to convert commitment to rural work. Undergraduate rural immersion is sufficient to create a graduate rural workforce that is far more mobile that was previously appreciated.

Dewaterability of sludge digested in extended aeration plants using ...

African Journals Online (AJOL)

Dewaterability of unconditioned sludge digested in full scale and lab scale experiments using either extended aeration (EA) or anaerobic digestion were compared on full and lab scale sand drying beds. Sludge digested in EA plants resulted in improvement in sludge dewaterability compared to sludge digested ...

Pressurized wet digestion in open vessels (T11)

International Nuclear Information System (INIS)

Kettisch, P.; Maichin, P.; Zischka, M.; Knapp, G.

2002-01-01

Full text: Pressurized wet digestion in closed vessels, microwave assisted or with conventional conductive heating, is the most important sample preparation technique for digestion or leaching procedures in element analysis. In comparison to open vessel digestion closed vessel digestion methods have many advantages, but there is one disadvantage - complex and expensive vessel designs. A new technique - pressurized wet digestion in open vessels - combine the advantages of closed vessel sample digestion with the application of simple and cheap open vessels made of quartz or PFA. The vessels are placed in a high pressure Asher HPA, which is adapted with a Teflon liner and filled partly with water. The analytical results with 30 ml quartz vessels, 22 ml PFA vessels and 1.5 ml PIA auto sampler cups will be shown. In principle every dimensions of vessels can be used. The vessels are loaded with sample material (max. 1.5 g with quartz vessels, max. 0.5 g with PFA vessels and 50 mg with auto sampler cups) and digestion reagent. Afterwards the vessels are simply covered with PTFE stoppers and not sealed. The vessels are transferred into a special adapted HPA and digested at temperatures up to 270 o C. The digestion time is 90 min. and cooling down to room temperature 30 min. The analytical results of CRM's are within the certified values and no cross contamination and losses of volatile elements could be observed. (author)

Sizing solar home systems for optimal development impact

International Nuclear Information System (INIS)

Bond, M.; Fuller, R.J.; Aye, Lu

2012-01-01

The paper compares the development impact of three different sized solar home systems (SHS) (10, 40 and 80 W p ) installed in rural East Timor. It describes research aimed to determine whether the higher cost of the larger systems was justified by additional household benefits. To assess the development impact of these different sizes of SHS the research used a combination of participatory and quantitative tools. Participatory exercises were conducted with seventy-seven small groups of SHS users in twenty-four rural communities and supplemented with a household survey of 195 SHS users. The combined results of these evaluation processes enabled the three sizes of SHS to be compared for two types of benefits—those associated with carrying out important household tasks and attributes of SHS which were advantageous compared to the use of non-electric lighting sources. The research findings showed that the small, 10 W p SHS provided much of the development impact of the larger systems. It suggests three significant implications for the design of SHS programs in contexts such as East Timor: provide more small systems rather than fewer large ones; provide lighting in the kitchen wherever possible; and carefully match SHS operating costs to the incomes of rural users. - Highlights: ► We compare development benefits for 3 sizes of solar home systems—10, 40 and 80 W p . ► Benefit assessment uses a combination of qualitative and quantitative approaches. ► Small systems are found to provide much of the benefits of the larger systems. ► To maximise benefits systems should be fitted with luminaires in kitchen areas. ► Financial benefits are important to users and may not accrue for large systems.

Acid-digestion treatment of plutonium-containing waste

International Nuclear Information System (INIS)

Wieczorek, H.; Kemmler, G.; Krause, H.

1981-01-01

The Radioactive Acid-Digestion Test Unit (RADTU) has been constructed at Hanford to demonstrate the application of the acid-digestion process for treating combustible transuranic wastes and scrap materials. The RADTU, with its original tray digestion vessel, has recently completed a six-month campaign processing potentially contaminated non-glovebox wastes from a Hanford plutonium facility. During this campaign, it processed 2100 kg largely cellulosic wastes at an average sustained processing rate of 3 kg/h as limited by the acid-waste contact and the water boil-off rate from the acid feeds. The on-line operating efficiency was nearly 50% on a twelve-hour day, five-day week basis. Following this campaign, a new annular high-rate digester has been installed for testing. In preliminary tests with simulated wastes, the new digester demonstrated a sustained capacity of 10 kg/h with greatly improved intimacy of contact between the digestion acid and the waste. The new design also doubles the heat-transfer surface, which is expected to provide at least twice the water boil-off rate of the previous tray digester design. Following shakedown testing with simulated and low-level wastes, the new unit will be used to process combustible plutonium scrap and waste from Hanford plutonium facilities for the purposes of volume reduction, plutonium recovery, and stabilization of the final waste form. (author)

Resistance of soil-bound prions to rumen digestion.

Directory of Open Access Journals (Sweden)

Samuel E Saunders

Full Text Available Before prion uptake and infection can occur in the lower gastrointestinal system, ingested prions are subjected to anaerobic digestion in the rumen of cervids and bovids. The susceptibility of soil-bound prions to rumen digestion has not been evaluated previously. In this study, prions from infectious brain homogenates as well as prions bound to a range of soils and soil minerals were subjected to in vitro rumen digestion, and changes in PrP levels were measured via western blot. Binding to clay appeared to protect noninfectious hamster PrP(c from complete digestion, while both unbound and soil-bound infectious PrP(Sc proved highly resistant to rumen digestion. In addition, no change in intracerebral incubation period was observed following active rumen digestion of unbound hamster HY TME prions and HY TME prions bound to a silty clay loam soil. These results demonstrate that both unbound and soil-bound prions readily survive rumen digestion without a reduction in infectivity, further supporting the potential for soil-mediated transmission of chronic wasting disease (CWD and scrapie in the environment.

Resistance of Soil-Bound Prions to Rumen Digestion

Science.gov (United States)

Saunders, Samuel E.; Bartelt-Hunt, Shannon L.; Bartz, Jason C.

2012-01-01

Before prion uptake and infection can occur in the lower gastrointestinal system, ingested prions are subjected to anaerobic digestion in the rumen of cervids and bovids. The susceptibility of soil-bound prions to rumen digestion has not been evaluated previously. In this study, prions from infectious brain homogenates as well as prions bound to a range of soils and soil minerals were subjected to in vitro rumen digestion, and changes in PrP levels were measured via western blot. Binding to clay appeared to protect noninfectious hamster PrPc from complete digestion, while both unbound and soil-bound infectious PrPSc proved highly resistant to rumen digestion. In addition, no change in intracerebral incubation period was observed following active rumen digestion of unbound hamster HY TME prions and HY TME prions bound to a silty clay loam soil. These results demonstrate that both unbound and soil-bound prions readily survive rumen digestion without a reduction in infectivity, further supporting the potential for soil-mediated transmission of chronic wasting disease (CWD) and scrapie in the environment. PMID:22937149

The Effect of Digestive Capacity on the Intake Rate of Toxic and Non-Toxic Prey in an Ecological Context.

Directory of Open Access Journals (Sweden)

Thomas Oudman

Full Text Available Digestive capacity often limits food intake rate in animals. Many species can flexibly adjust digestive organ mass, enabling them to increase intake rate in times of increased energy requirement and/or scarcity of high-quality prey. However, some prey species are defended by secondary compounds, thereby forcing a toxin limitation on the forager's intake rate, a constraint that potentially cannot be alleviated by enlarging digestive capacity. Hence, physiological flexibility may have a differential effect on intake of different prey types, and consequently on dietary preferences. We tested this effect in red knots (Calidris canutus canutus, medium-sized migratory shorebirds that feed on hard-shelled, usually mollusc, prey. Because they ingest their prey whole and crush the shell in their gizzard, the intake rate of red knots is generally constrained by digestive capacity. However, one of their main prey, the bivalve Loripes lucinalis, imposes a toxin constraint due to its symbiosis with sulphide-oxidizing bacteria. We manipulated gizzard sizes of red knots through prolonged exposure to hard-shelled or soft foods. We then measured maximum intake rates of toxic Loripes versus a non-toxic bivalve, Dosinia isocardia. We found that intake of Dosinia exponentially increased with gizzard mass, confirming earlier results with non-toxic prey, whereas intake of Loripes was independent of gizzard mass. Using linear programming, we show that this leads to markedly different expected diet preferences in red knots that try to maximize energy intake rate with a small versus a large gizzard. Intra- and inter-individual variation in digestive capacity is found in many animal species. Hence, the here proposed functional link with individual differences in foraging decisions may be general. We emphasize the potential relevance of individual variation in physiology when studying trophic interactions.

Characteristics of randomised trials on diseases in the digestive system registered in ClinicalTrials.gov: a retrospective analysis

DEFF Research Database (Denmark)

Wildt, Signe; Krag, Aleksander; Gluud, Liselotte

2011-01-01

Objectives To evaluate the adequacy of reporting of protocols for randomised trials on diseases of the digestive system registered in http://ClinicalTrials.gov and the consistency between primary outcomes, secondary outcomes and sample size specified in http://ClinicalTrials.gov and published...

Diurnal variation in ruminal pH on the digestibility of highly digestible perennial ryegrass during continuous culture fermentation.

Science.gov (United States)

Wales, W J; Kolver, E S; Thorne, P L; Egan, A R

2004-06-01

Dairy cows grazing high-digestibility pastures exhibit pronounced diurnal variation in ruminal pH, with pH being below values considered optimal for digestion. Using a dual-flow continuous culture system, the hypothesis that minimizing diurnal variation in pH would improve digestion of pasture when pH was low, but not at a higher pH, was tested. Four treatments were imposed, with pH either allowed to exhibit normal diurnal variation around an average pH of 6.1 or 5.6, or maintained at constant pH. Digesta samples were collected during the last 3 d of each of four, 9-d experimental periods. A constant pH at 5.6 compared with a constant pH of 6.1 reduced the digestibility of organic matter (OM), neutral detergent (NDF), and acid detergent fiber (ADF) by 7, 14, and 21%, respectively. When pH was allowed to vary (averaging 5.6), digestion of OM, NDF, and ADF were reduced by 15,30, and 36%, respectively, compared with pH varying at 6.1. There was little difference in digestion parameters when pH was either constant or varied with an average pH of 6.1. However, when average pH was 5.6, maintaining a constant pH significantly increased digestion of OM, NDF, and ADF by 5, 25, and 24% compared with a pH that exhibited normal diurnal variation. These in vitro results show that gains in digestibility and potential milk production can be made by minimizing diurnal variation in ruminal pH, but only when ruminal pH is low (5.6). However, larger gains in productivity can be achieved by increasing average daily ruminal pH from 5.6 to 6.1.

Effect of physical effectiveness on digestibility of ration for cows in early lactation.

Science.gov (United States)

Stojanovic, B; Grubic, G; Djordjevic, N; Bozickovic, A; Ivetic, A; Davidovic, V

2014-08-01

A study was conducted to investigate the effects of a diet particle size on nutrient digestibility in cows in early lactation. Treatments were diets with forage to concentrate ratio 43:57% in diet dry matter, with four different physically effective fibres (peNDF) content based on different cut length of corn silage and alfalfa haylage. The physical effectiveness factors (pef) and peNDF content of TMRs (total mixed ration) were determined using Penn State Particle Separator (PSPS) with two (pef8.0 , peNDF8.0) or three (pef1.18, peNDF1.18) sieves. The reducing of cut length of forages and particle size of diets did not affect on dry matter intake, while decreased peNDF intake by 16.34 and 8.83%, for peNDF8.0 and peNDF1.18 respectively. Apparent total tract digestibility of the nutrients was measured using two indicators: acid insoluble ash (AIA) and acid detergent insoluble lignin (ADL). Decreasing of forages cut length significantly increased apparent total tract digestibility of neutral detergent fibre (NDF) from 48.39% to 53.84% and from 53.9% to 58.66%, of crude protein from 73.96% to 79.24% and from 71.56% to 77.90%, with contemporary decreasing of non-fibre carbohydrate from 90.89% to 84.81% and from 91.99% to 86.80%, with AIA or ADL as indicator respectively. Dietary value of net energy for lactation (NEL) and energy intake was not affected by the peNDF content of the diet. Journal of Animal Physiology and Animal Nutrition © 2013 Blackwell Verlag GmbH.

Cayuga County Regional Digester: Vision Becomes Reality. Final Report

Energy Technology Data Exchange (ETDEWEB)

Zadeh, Kamyar V. [Blue Electron Technology Solutions International LLC, Manlius, NY (United States); Young, Jim [Cayuga Soil and Water Conservation District, Auburn, NY (United States)

2013-03-12

With an average herd size of 113 mature cows, Cayuga County is home to 280 dairy farms and 31,500 dairy milking cows producing approximately 855 million gallons of milk per year. The Cayuga Dairy industry is a major contributor to the countys economy, employing nearly 1200 people, while generating $140,000,000 of revenue from sale of milk alone. At the same time, the Cayuga County dairy industry also produces 5.7 million gallons of manure daily: (a) Nearly 34% of this manure is produced on smaller farms. (b) Digesters are expensive pieces of equipment and require attention and care. ( c) The on-farm digester systems have fairly long payback (>10 years) even for larger CAFO farms (>1000 milking cows). In 2005, Cayuga County Soil and Water Conservation District (The District), a Public Agency under Cayuga County, decided to undertake a centralized community digester project. The primary goal of the project was to develop an economically sustainable model, under the auspices of The District to address manure management issues facing the smaller dairies, improve the water quality and improve the quality of life for Cayuga County residents. It is believed that the District has accomplished this goal by completing construction of Cayuga County Regional Digester on a parcel of land behind the Cayuga County Natural Resource Center located at 7413 County House Road in the Town of Sennett in Cayuga County, New York. The digester facility consists of the following major components. 1. Transfer Station: This an indoor truck bay, where 35,000 gallons of manure from three local farms, 8,500 gallons of liquid organic food-processor waste, and 1,200 gallons of brown grease are unloaded from tanker trucks and the digested slurry is loaded onto the tanker trucks for delivery back to the participating farms. 2. Anaerobic Digester: The project utilizes a hydraulic mix anaerobic digester, a unique design that has no internal moving parts for mixing. The digester, which operates at

Design considerations for a farm-scale biogas plant based on pilot-scale anaerobic digesters loaded with rice straw and piggery wastewater

International Nuclear Information System (INIS)

Mussoline, Wendy; Esposito, Giovanni; Lens, Piet; Garuti, Gilberto; Giordano, Andrea

2012-01-01

Two pilot-scale (1 m 3 ) digesters filled with untreated rice straw and co-digested with raw pig wastewater were operated to obtain design parameters for a farm-scale biogas plant. Both digesters contained 50 kg of dry straw mixed with diluted pig wastewater to create dry digestion conditions (20% TS) and operated for 189 days with leachate recirculation. Digester A was designed for optimum performance (150 L of pig wastewater and mesophilic temperatures) while Digester B was designed to establish minimum inputs (60 L of pig wastewater at ambient temperatures). The pig wastewater provided sufficient buffering capacity to maintain appropriate pH values (between 7.0 and 8.1) and nutrient balances (TOC to TKN ratios of 20 in Digester A and 32 in Digester B). Total biogas production was 22,859 L in Digester A and 1420 L from Digester B, resulting in specific methane yields of 231 and 12 L CH 4 /kgVS added, respectively. Gas production in Digester A was directly correlated with temperature, but the overall lack of methanogenic activity was caused primarily by the reduced wastewater volume. Two theoretical farm-scale scenarios (considering both untreated and pretreated rice straw) were developed for a 100-ha rice farm. Either scenario can produce 100,000 m 3 CH 4 per year, yielding 328 MWh. Major differences including heat input, space requirements, loading frequency, digester volume, engine size, wastewater quantities, and additives are quantitatively defined. The appropriate choice for a farm-scale operation is the simplest model using untreated rice straw without additives, although six times more heat and twice as much reactor volume is required. -- Highlights: ► The co-digestion of untreated rice straw and piggery wastewater is investigated. ► Gas production increases with the volume of pig wastewater added and temperature. ► Pig wastewater alone can provide appropriate buffering capacity and nutrient balance. ► Pilot-scale results are used to establish

The Effects of Different Energy and Protein Ratio to Sheep’s Nutrient Intake and Digestibility

Directory of Open Access Journals (Sweden)

Sri Mawati

2013-06-01

Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} The objective of this research was to study the effects of different energy and protein ratio towards sheep’s nutrient intake and digestibility. Twenty four male sheep’s, 6 – 7 months old with initial average live weight 13+1.56 kg, coefficient variant11.78% were used in this research. The complete feed ration which consisted of King Grass (Pennisetum purpureum, soybean powder, rice bran, dried cassava and molasses was used in this research. Protein content on each component was 10, 12 and 14% and total digestible nutrients (TDN 60 and 65%, respectively. Dry matter (DM and organic matter (OM intake, DM and OM digestibility were studied in this research. Analysis of variance (ANOVA was employed to analyze the data. Test of Small Difference (P<0.05 was then carried out if significant different occurred. The research results showed that Dry matter and OM ration intake showed significant different among treatments (P<0.05. The highest DM intake was obtained at crude protein (CP 14% and TDN 65% i.e. 695.54 g while the lowest value was CP 14% and TDN 65% i.e. 462.11 g. Thus different DM and OM intake were caused by different ration ingredients composition. Dry matter and OM ration digestibility were not show

Environmental assessment of digestate treatment technologies using LCA methodology.

Science.gov (United States)

Vázquez-Rowe, Ian; Golkowska, Katarzyna; Lebuf, Viooltje; Vaneeckhaute, Céline; Michels, Evi; Meers, Erik; Benetto, Enrico; Koster, Daniel

2015-09-01

The production of biogas from energy crops, organic waste and manure has augmented considerably the amounts of digestate available in Flanders. This has pushed authorities to steadily introduce legislative changes to promote its use as a fertilising agent. There is limited arable land in Flanders, which entails that digestate has to compete with animal manure to be spread. This forces many anaerobic digestion plants to further treat digestate in such a way that it can either be exported or the nitrogen be removed. Nevertheless, the environmental impact of these treatment options is still widely unknown, as well as the influence of these impacts on the sustainability of Flemish anaerobic digestion plants in comparison to other regions where spreading of raw digestate is allowed. Despite important economic aspects that must be considered, the use of Life Cycle Assessment (LCA) is suggested in this study to identify the environmental impacts of spreading digestate directly as compared to four different treatment technologies. Results suggest relevant environmental gains when the digestate mix is treated using the examined conversion technologies prior to spreading, although important trade-offs between impact categories were observed and discussed. The promising results of digestate conversion technologies suggest that further LCA analyses should be performed to delve into, for instance, the appropriateness to shift to nutrient recovery technologies rather than digestate conversion treatments. Copyright © 2015 Elsevier Ltd. All rights reserved.

Acid digestion of combustible wastes: a status report

International Nuclear Information System (INIS)

Lerch, R.E.

1975-05-01

Work at the Hanford Engineering Development Laboratory on development of the acid digestion process for treating combustible wastes is discussed. Materials such as paper, rubber, and plastics are readily decomposed into a low volume, noncombustible residue. Engineering results using the Acid Digestion Test Unit are discussed. Tests to date generally duplicated earlier laboratory results with respect to waste processing rates, volume reduction, off-gas generation rates and volumes, acid consumption, and completeness of reaction. Demonstrated processing rates were as high as 5 kg/hr for short duration run periods. The tests indicated engineering feasibility of the acid digestion process and showed acid digestion to be a potentially attractive method for treating combustible nuclear wastes. Other areas discussed in the report are behavior of plutonium and americium during acid digestion, behavior of various construction materials, and safety. An integrated flowsheet for operation of an acid digestion unit is also presented. (U.S.)

A meta-analysis of feed digestion in dairy cows. 1. The effects of forage and concentrate factors on total diet digestibility.

Science.gov (United States)

Nousiainen, J; Rinne, M; Huhtanen, P

2009-10-01

A meta-analysis based on published experiments with lactating dairy cows was conducted to study the effects of dietary forage and concentrate factors on apparent total diet digestibility. A data set was collected that included a total of 497 dietary treatment means from 92 studies. The diets were based on grass silage or on legume or whole-crop cereal silages partly or completely substituted for grass silage. The silages were supplemented with concentrates given at a flat rate within a dietary comparison. For the statistical evaluation, the data were divided into 5 subsets to quantify silage (digestibility, 42 diets in 17 studies; fermentation characteristics, 108 diets in 39 studies) and concentrate (amount of supplementation, 142 diets in 59 studies; concentration of crude protein, 215 diets in 82 studies; carbohydrate composition, 66 diets in 23 studies) factors on total diet digestibility. The diet digestibility of dairy cows was determined by total fecal collection or by using acid-insoluble ash as an internal marker. Diet organic matter digestibility (OMD) at a maintenance level of feeding (OMD(m)) was estimated using sheep in vivo or corresponding in vitro digestibility values for the forage and reported ingredient and chemical composition values, with tabulated digestibility coefficients for the concentrate components of the diet. A mixed model regression analysis was used to detect the responses of different dietary factors on apparent total diet digestibility. Improved silage OMD(m) resulting from earlier harvest was translated into improved production-level OMD in cows (OMD(p)). The effects of silage fermentation characteristics on OMD(p) were quantitatively small, although sometimes significant. Concentrate supplementation improved total diet OMD(m), but this was not realized in lactating dairy cows because of linearly decreased neutral detergent fiber (NDF) digestibility as concentrate intake increased. Increasing the concentrate crude protein amount

Variation in In Vitro Digestibility of Barley Protein

DEFF Research Database (Denmark)

Buchmann, N. B.

1979-01-01

impaired digestibilities; these findings were partially verified in a repeated field trial, but were not confirmed in vivo. In vitro digestibilities of barleys grown in pots at various N-levels were positively correlated with protein or hordein content. In vitro digestibility was negatively correlated...

Composition and Digestibility of Deer Browse in Southern Forests

Science.gov (United States)

Henry L. Short; Robert M. Blair; E.A. Epps

1975-01-01

Twigs were most nutritious and digestible during early growth in spring; they were high in fiber content and low in digestibility during summer, autumn, and winter. Evergreen leaves did not vary substantially in nutrient content and digestibility throughout the year. By contrast, leaves of deciduous species were reduced in quality and digestibility after leaf-fall....

Importance of latrine communication in European rabbits shifts along a rural-to-urban gradient.

Science.gov (United States)

Ziege, Madlen; Bierbach, David; Bischoff, Svenja; Brandt, Anna-Lena; Brix, Mareike; Greshake, Bastian; Merker, Stefan; Wenninger, Sandra; Wronski, Torsten; Plath, Martin

2016-06-14

Information transfer in mammalian communication networks is often based on the deposition of excreta in latrines. Depending on the intended receiver(s), latrines are either formed at territorial boundaries (between-group communication) or in core areas of home ranges (within-group communication). The relative importance of both types of marking behavior should depend, amongst other factors, on population densities and social group sizes, which tend to differ between urban and rural wildlife populations. Our study is the first to assess (direct and indirect) anthropogenic influences on mammalian latrine-based communication networks along a rural-to-urban gradient in European rabbits (Oryctolagus cuniculus) living in urban, suburban and rural areas in and around Frankfurt am Main (Germany). The proportion of latrines located in close proximity to the burrow was higher at rural study sites compared to urban and suburban ones. At rural sites, we found the largest latrines and highest latrine densities close to the burrow, suggesting that core marking prevailed. By contrast, latrine dimensions and densities increased with increasing distance from the burrow in urban and suburban populations, suggesting a higher importance of peripheral marking. Increased population densities, but smaller social group sizes in urban rabbit populations may lead to an increased importance of between-group communication and thus, favor peripheral over core marking. Our study provides novel insights into the manifold ways by which man-made habitat alterations along a rural-to-urban gradient directly and indirectly affect wildlife populations, including latrine-based communication networks.

Discourses of Disability in the "Digest."

Science.gov (United States)

Barton, Ellen

2001-01-01

Presents an account of the discourse of disability in the "Reader's Digest" during its first 30 years (1922-1952). Concludes that the construction of disability in the "Digest" raises important questions that should enter the field of disability studies. (PM)

Characterizing Rural Food Access in Remote Areas.

Science.gov (United States)

Bardenhagen, Chris J; Pinard, Courtney A; Pirog, Rich; Yaroch, Amy Lazarus

2017-10-01

Residents of rural areas may have limited access to healthy foods, leading to higher incidence of diet related health issues. Smaller grocers in rural areas experience challenges in maintaining fresh produce and other healthy foods available for customers. This study assessed the rural food environment in northeast Lower Michigan in order to inform healthy food financing projects such as the Michigan Good Food Fund. The area's retail food businesses were categorized using secondary licensing, business, and nutrition program databases. Twenty of these stores were visited in person to verify the validity of the categories created, and to assess the availability of healthy foods in their aisles. In-depth interviews with key informants were carried out with store owners, economic development personnel, and other food system stakeholders having knowledge about food access, in order to learn more about the specific challenges that the area faces. Out-shopping, seasonality, and economic challenges were found to affect healthy food availability. Mid-sized independent stores were generally found to have a larger selection of healthy foods, but smaller rural groceries also have potential to provide fresh produce and increase food access. Potential healthy food financing projects are described and areas in need of further research are identified.

Microalgal Cultivation in Treating Liquid Digestate from Biogas Systems.

Science.gov (United States)

Xia, Ao; Murphy, Jerry D

2016-04-01

Biogas production via anaerobic digestion (AD) has rapidly developed in recent years. In addition to biogas, digestate is an important byproduct. Liquid digestate is the major fraction of digestate and may contain high levels of ammonia nitrogen. Traditional processing technologies (such as land application) require significant energy inputs and raise environmental risks (such as eutrophication). Alternatively, microalgae can efficiently remove the nutrients from digestate while producing high-value biomass that can be used for the production of biochemicals and biofuels. Both inorganic and organic carbon sources derived from biogas production can significantly improve microalgal production. Land requirement for microalgal cultivation is estimated as 3% of traditional direct land application of digestate. Copyright © 2015 Elsevier Ltd. All rights reserved.

Understanding the Effect of Particle Size and Processing on Almond Lipid Bioaccessibility through Microstructural Analysis: From Mastication to Faecal Collection

Science.gov (United States)

Mandalari, Giuseppina; Parker, Mary L.; Bisignano, Carlo; Raciti, Roberto; Baer, David J.; Wilde, Peter J.

2018-01-01

We have previously reported on the low lipid bioaccessibility from almond seeds during digestion in the upper gastrointestinal tract (GIT). In the present study, we quantified the lipid released during artificial mastication from four almond meals: natural raw almonds (NA), roasted almonds (RA), roasted diced almonds (DA) and almond butter from roasted almonds (AB). Lipid release after mastication (8.9% from NA, 11.8% from RA, 12.4% from DA and 6.2% from AB) was used to validate our theoretical mathematical model of lipid bioaccessibility. The total lipid potentially available for digestion in AB was 94.0%, which included the freely available lipid resulting from the initial sample processing and the further small amount of lipid released from the intact almond particles during mastication. Particle size distributions measured after mastication in NA, RA and DA showed most of the particles had a size of 1000 µm and above, whereas AB bolus mainly contained small particles (<850 µm). Microstructural analysis of faecal samples from volunteers consuming NA, RA, DA and AB confirmed that some lipid in NA, RA and DA remained encapsulated within the plant tissue throughout digestion, whereas almost complete digestion was observed in the AB sample. We conclude that the structure and particle size of the almond meals are the main factors in regulating lipid bioaccessibility in the gut. PMID:29443942

Understanding the Effect of Particle Size and Processing on Almond Lipid Bioaccessibility through Microstructural Analysis: From Mastication to Faecal Collection

Directory of Open Access Journals (Sweden)

Giuseppina Mandalari

2018-02-01

Full Text Available We have previously reported on the low lipid bioaccessibility from almond seeds during digestion in the upper gastrointestinal tract (GIT. In the present study, we quantified the lipid released during artificial mastication from four almond meals: natural raw almonds (NA, roasted almonds (RA, roasted diced almonds (DA and almond butter from roasted almonds (AB. Lipid release after mastication (8.9% from NA, 11.8% from RA, 12.4% from DA and 6.2% from AB was used to validate our theoretical mathematical model of lipid bioaccessibility. The total lipid potentially available for digestion in AB was 94.0%, which included the freely available lipid resulting from the initial sample processing and the further small amount of lipid released from the intact almond particles during mastication. Particle size distributions measured after mastication in NA, RA and DA showed most of the particles had a size of 1000 µm and above, whereas AB bolus mainly contained small particles (<850 µm. Microstructural analysis of faecal samples from volunteers consuming NA, RA, DA and AB confirmed that some lipid in NA, RA and DA remained encapsulated within the plant tissue throughout digestion, whereas almost complete digestion was observed in the AB sample. We conclude that the structure and particle size of the almond meals are the main factors in regulating lipid bioaccessibility in the gut.

Quarterly intrinsic disorder digest (January-February-March, 2014)

OpenAIRE

DeForte, Shelly; Reddy, Krishna D.; Uversky, Vladimir N.

2016-01-01

This is the 5th issue of the Digested Disorder series that represents a reader's digest of the scientific literature on intrinsically disordered proteins. We continue to use only 2 criteria for inclusion of a paper to this digest: The publication date (a paper should be published within the covered time frame) and the topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the first quarter of 2014; i.e., during ...

In vitro gastrointestinal digestion study of a novel bio-tofu with special emphasis on the impact of microbial transglutaminase

Directory of Open Access Journals (Sweden)

Guangliang Xing

2016-12-01

Full Text Available We have developed a novel bio-tofu, made from mixed soy and cow milk (MSCM, using Lactobacillus helveticus MB2-1 and Lactobacillus plantarum B1-6 incorporated with microbial transglutaminase (MTGase as coagulant. MTGase was added to improve the textural properties and suit for cooking. However, the effect of MTGase on the digestion of mixed-protein fermented by lactic acid bacteria was unclear. This study aimed at evaluating the effect of MTGase on protein digestion of bio-tofu under simulated gastrointestinal digestion condition. The results showed that addition of MTGase could affect the particle size distribution, degree of hydrolysis, the content of soluble proteins and free amino acids. Based on the electrophoresis data, MTGase addition enhanced protein polymerization. During gastric and intestinal digestion process, proteins from bio-tofu were degraded into low molecular mass peptides. Our results suggested that incorporation of MTGase could lead to enzymatic modification of proteins of bio-tofu which may help in controlling energy intake and decrease the chance of food allergy.

In vitro gastrointestinal digestion study of a novel bio-tofu with special emphasis on the impact of microbial transglutaminase

Science.gov (United States)

Xing, Guangliang; Rui, Xin; Jiang, Mei; Xiao, Yu; Guan, Ying; Wang, Dan

2016-01-01

We have developed a novel bio-tofu, made from mixed soy and cow milk (MSCM), using Lactobacillus helveticus MB2-1 and Lactobacillus plantarum B1-6 incorporated with microbial transglutaminase (MTGase) as coagulant. MTGase was added to improve the textural properties and suit for cooking. However, the effect of MTGase on the digestion of mixed-protein fermented by lactic acid bacteria was unclear. This study aimed at evaluating the effect of MTGase on protein digestion of bio-tofu under simulated gastrointestinal digestion condition. The results showed that addition of MTGase could affect the particle size distribution, degree of hydrolysis, the content of soluble proteins and free amino acids. Based on the electrophoresis data, MTGase addition enhanced protein polymerization. During gastric and intestinal digestion process, proteins from bio-tofu were degraded into low molecular mass peptides. Our results suggested that incorporation of MTGase could lead to enzymatic modification of proteins of bio-tofu which may help in controlling energy intake and decrease the chance of food allergy. PMID:27994970

Processing biogas planet digestates into value-added products -BIOVIRTA

Energy Technology Data Exchange (ETDEWEB)

Paavola, T.; Rintala, J. (MTT Agrifood Research Finland, Jokioinen (Finland)), Email: teija.paavola@mtt.fi; Sahltroem, L.; Maunuksela, L.; Torniainen, M. (Finnish Food Safety Authority, EVIRA, Helsinki (Finland)), Email: leena.sahlstrom@evira.fi; Kaparaju, P.; Rintala, J. (Univ. of Jyvaeskylae (Finland)), Email: jukka.rintala@jyu.fi; Vikman, M.; Kapanen, A. (VTT Technical Research Centre of Finland, Espoo (Finland)), Email: minna.vikman@vtt.fi

2010-10-15

The objective of BIOVIRTA project is to develop technologies and practices with which digestates, originating from anaerobic digestion of different organic wastes and by-products, can be refined to value-added and safe products for various end-uses. It is expected that the operational preconditions for biogas plants will be significantly enhanced when the end-products are proven safe and applicable. Selection of the raw materials for anaerobic codigestion is the main operational strategy that could influence the nutrient content in the digestate. This has been clearly established in the laboratory and full-scale studies with various digestates originating from different raw materials, e.g. rendering and slaughterhouse byproducts. The nutrient content in the digestate also affects the opportunities to produce refined digestate products. In this project, the possibilities for several processing technologies, e.g. mechanical separation and stripping, have been intensively evaluated for the production of different digestate products. Their mass balances have also been estimated. The feasibility for the use of the digestate products has been assessed based on their chemical and hygienic quality and for various end-uses, including as organic fertiliser and/or soil improver in crop production. The preliminary results of these field-experiments showed that the yield of barley fertilised with digestate products was comparable to inorganic fertilisers. (orig.)

In vitro digestibility of individual amino acids in rumen-undegraded protein: the modified three-step procedure and the immobilized digestive enzyme assay.

Science.gov (United States)

Boucher, S E; Calsamiglia, S; Parsons, C M; Stern, M D; Moreno, M Ruiz; Vázquez-Añón, M; Schwab, C G

2009-08-01

Three soybean meal, 3 SoyPlus (West Central Cooperative, Ralston, IA), 5 distillers dried grains with solubles, and 5 fish meal samples were used to evaluate the modified 3-step in vitro procedure (TSP) and the in vitro immobilized digestive enzyme assay (IDEA; Novus International Inc., St. Louis, MO) for estimating digestibility of AA in rumen-undegraded protein (RUP-AA). In a previous experiment, each sample was ruminally incubated in situ for 16 h, and in vivo digestibility of AA in the intact samples and in the rumen-undegraded residues (RUR) was obtained for all samples using the precision-fed cecectomized rooster assay. For the modified TSP, 5 g of RUR was weighed into polyester bags, which were then heat-sealed and placed into Daisy(II) incubator bottles. Samples were incubated in a pepsin/HCl solution followed by incubation in a pancreatin solution. After this incubation, residues remaining in the bags were analyzed for AA, and digestibility of RUP-AA was calculated based on disappearance from the bags. In vitro RUP-AA digestibility estimates obtained with this procedure were highly correlated to in vivo estimates. Corresponding intact feeds were also analyzed via the pepsin/pancreatin steps of the modified TSP. In vitro estimates of AA digestibility of the feeds were highly correlated to in vivo RUP-AA digestibility, which suggests that the feeds may not need to be ruminally incubated before determining RUP-AA digestibility in vitro. The RUR were also analyzed via the IDEA kits. The IDEA values of the RUR were good predictors of RUP-AA digestibility in soybean meal, SoyPlus, and distillers dried grains with solubles, but the IDEA values were not as good predictors of RUP-AA digestibility in fish meal. However, the IDEA values of intact feed samples were also determined and were highly correlated to in vivo RUP-AA digestibility for all feed types, suggesting that the IDEA value of intact feeds may be a better predictor of RUP-AA digestibility than the IDEA

Digestibility coefficient and true digestible amino acid values of different cultivars of maize for poultry

Directory of Open Access Journals (Sweden)

Márcia Antonia Bartolomeu Agustini

2015-04-01

Full Text Available The digestibility and true digestible amino acid content of eight cultivars of maize was determined using the method of force-feeding roosters cecectomized. The experimental design was completely randomized, represented by eight cultivars, five replicates and a rooster each. Five roosters were kept fasting for corrections corresponding to metabolic and endogenous losses of amino acids. Significant differences (P <0.05 among maize cultivars for the true digestibility of amino acids, methionine, threonine, arginine, cystine and serine were observed. The values of true digestibility coefficients for essential amino acids, for methionine, threonine and arginine ranged from 85.61 to 93.57%, from 66.27 to 84.97% and 83.39 to 93.10% respectively. For the other essential amino acids, the average values were: 72.84% for lysine, 85.64% for methionine+cystine, 87.29% for histidine, 85.33% for valine, 87.11% for isoleucine, 94.04% for leucine and 90.65% for phenylalanine. The true digestibility coefficients of nonessential amino acids cystine and serine that showed significant difference ranged from 73.97 to 89.21% and from 77.31 to 92.68%, respectively. For other non-essential amino acids, average values were 88.28% for alanine, 82.68% for aspartic acid, 92.19% for glutamic acid and 87.84% for tyrosine. Due to the variations observed, it is recommended periodic analyzes of maize cultivars used to formulate diets, to ensure the feed quality and the performance of the animals.

Comparative economic analysis: Anaerobic digester case study

International Nuclear Information System (INIS)

Lusk, P.D.

1991-01-01

An economic guide is developed to assess the value of anaerobic digesters used on dairy farms. Two varieties of anaerobic digesters, a conventional mixed-tank mesophilic and an innovative earthen psychrophilic, are comparatively evaluated using a cost-effectiveness index. The two case study examples are also evaluated using three other investment merit statistics: simple payback period, net present value, and internal rate of return. Life-cycle savings are estimated for both varieties, with sensitivities considered for investment risk. The conclusion is that an earthen psychrophilic digester can have a significant economic advantage over a mixed-tank mesophilic digester because of lower capital cost and reduced operation and maintenance expenses. Because of this economic advantage, additional projects are being conducted in North Carolina to increase the rate of biogas utilization. The initial step includes using biogas for milk cooling at the dairy farm where the existing psychrophilic digester is located. Further, a new project is being initiated for electricity production with thermal reclaim at a swine operation

Anaerobic digestion of hog wastes

Energy Technology Data Exchange (ETDEWEB)

Taiganides, E P; Baumann, E R; Johnson, H P; Hazen, T E

1963-01-01

A short history, a list of advantages and limitations, and a short introduction to the principles of the process of anaerobic digestion are given. Six five gallon bottle digesters were daily fed hog manure, maintained at 35/sup 0/C, and constantly agitated. Satisfactory operation was assured at 3.2 g VS/l/day with a detention time of 10 days, yielding 490-643 ml gas/g VS/day with a CH/sub 4/ content of 59% (2.1 x 10/sup 7/ joules/m/sup 3/). A figure and discussion portray the interrelationships of loading rate, solids concentration and detention time. They estimate that a marginal profit might be obtained by the operation of a heated digester handling the wastes of 10,000 hogs.

Digestive morphophysiology of Gryllodes sigillatus (Orthoptera: Gryllidae).

Science.gov (United States)

Biagio, Fernanda P; Tamaki, Fabio K; Terra, Walter R; Ribeiro, Alberto F

2009-12-01

The evolution of the digestive system in the Order Orthoptera is disclosed from the study of the morphophysiology of the digestive process in its major taxa. This paper deals with a cricket representing the less known suborder Ensifera. Most amylase and trypsin activities occur in crop and caeca, respectively. Maltase and aminopeptidase are found in soluble and membrane-bound forms in caeca, with aminopeptidase also occurring in ventriculus. Amaranth was orally fed to Gryllodes sigillatus adults or injected into their haemolymph. The experiments were performed with starving and feeding insects with identical results. Following feeding of the dye the luminal side of the most anterior ventriculus (and in lesser amounts the midgut caeca) became heavily stained. In injected insects, the haemal side of the most posterior ventriculus was stained. This suggested that the anterior ventriculus is the main site of water absorption (the caeca is a secondary one), whereas the posterior ventriculus secretes water into the gut. Thus, a putative counter-current flux of fluid from posterior to anterior ventriculus may propel digestive enzyme recycling. This was confirmed by the finding that digestive enzymes are excreted at a low rate. The fine structure of midgut caeca and ventriculus cells revealed that they have morphological features that may be related to their involvement in secretion (movement from cell to lumen) and absorption (movement from lumen to cell) of fluids. Furthermore, morphological data showed that both merocrine and apocrine secretory mechanisms occur in midgut cells. The results showed that cricket digestion differs from that in grasshopper in having: (1) more membrane-bound digestive enzymes; (2) protein digestion slightly displaced toward the ventriculus; (3) midgut fluxes, and hence digestive enzyme recycling, in both starved and fed insects.

Anaerobic digestion and co-digestion of slaughterhouse waste (SHW): influence of heat and pressure pre-treatment in biogas yield.

Science.gov (United States)

Cuetos, M J; Gómez, X; Otero, M; Morán, A

2010-10-01

Mesophilic anaerobic digestion (34+/-1 degrees C) of pre-treated (for 20 min at 133 degrees C, >3 bar) slaughterhouse waste and its co-digestion with the organic fraction of municipal solid waste (OFMSW) have been assessed. Semi-continuously-fed digesters worked with a hydraulic retention time (HRT) of 36 d and organic loading rates (OLR) of 1.2 and 2.6 kg VS(feed)/m(3)d for digestion and co-digestion, respectively, with a previous acclimatization period in all cases. It was not possible to carry out an efficient treatment of hygienized waste, even less so when OFMSW was added as co-substrate. These digesters presented volatile fatty acids (VFA), long chain fatty acids (LCFA) and fats accumulation, leading to instability and inhibition of the degradation process. The aim of applying a heat and pressure pre-treatment to promote splitting of complex lipids and nitrogen-rich waste into simpler and more biodegradable constituents and to enhance biogas production was not successful. These results indicate that the temperature and the high pressure of the pre-treatment applied favoured the formation of compounds that are refractory to anaerobic digestion. The pre-treated slaughterhouse wastes and the final products of these systems were analyzed by FTIR and TGA. These tools verified the existence of complex nitrogen-containing polymers in the final effluents, confirming the formation of refractory compounds during pre-treatment. (c) 2010 Elsevier Ltd. All rights reserved.

- Invited Review - Calcium Digestibility and Metabolism in Pigs*

Science.gov (United States)

González-Vega, J. C.; Stein, H. H.

2014-01-01

Calcium (Ca) and phosphorus (P) are minerals that have important physiological functions in the body. For formulation of diets for pigs, it is necessary to consider an appropriate Ca:P ratio for an adequate absorption and utilization of both minerals. Although both minerals are important, much more research has been conducted on P digestibility than on Ca digestibility. Therefore, this review focuses on aspects that are important for the digestibility of Ca. Only values for apparent total tract digestibility (ATTD) of Ca have been reported in pigs, whereas values for both ATTD and standardized total tract digestibility (STTD) of P in feed ingredients have been reported. To be able to determine STTD values for Ca it is necessary to determine basal endogenous losses of Ca. Although most Ca is absorbed in the small intestine, there are indications that Ca may also be absorbed in the colon under some circumstances, but more research to verify the extent of Ca absorption in different parts of the intestinal tract is needed. Most P in plant ingredients is usually bound to phytate. Therefore, plant ingredients have low digestibility of P due to a lack of phytase secretion by pigs. During the last 2 decades, inclusion of microbial phytase in swine diets has improved P digestibility. However, it has been reported that a high inclusion of Ca reduces the efficacy of microbial phytase. It is possible that formation of insoluble calcium-phytate complexes, or Ca-P complexes, not only may affect the efficacy of phytase, but also the digestibility of P and Ca. Therefore, Ca, P, phytate, and phytase interactions are aspects that need to be considered in Ca digestibility studies. PMID:25049919

Soil sample preparation using microwave digestion for uranium analysis

International Nuclear Information System (INIS)

Mohagheghi, Amir H.; Preston, Rose; Akbarzadeh, Mansoor; Bakthiar, Steven

2000-01-01

A new sample preparation procedure has been developed for digestion of soil samples for uranium analysis. The technique employs a microwave oven digestion system to digest the sample and to prepare it for separation chemistry and analysis. The method significantly reduces the volume of acids used, eliminates a large fraction of acid vapor emissions, and speeds up the analysis time. The samples are analyzed by four separate techniques: Gamma Spectrometry, Alpha Spectroscopy using the open digestion method, Kinetic Phosphorescence Analysis (KPA) using open digestion, and KPA by Microwave digestion technique. The results for various analytical methods are compared and used to confirm the validity of the new procedure. The details of the preparation technique along with its benefits are discussed

In vitro digestibility of goat milk and kefir with a new standardised static digestion method (INFOGEST cost action) and bioactivities of the resultant peptides.

Science.gov (United States)

Nehir El, Sedef; Karakaya, Sibel; Simsek, Sebnem; Dupont, Didier; Menfaatli, Esra; Eker, Alper Tolga

2015-07-01

The hydrolysis degrees of goat milk and kefir during simulated gastrointestinal digestion and some bioactivities of the resulting peptides after fermentation and digestion were studied. A static in vitro digestion method by the COST FA1005 Action INFOGEST was used and goat milk and kefir were partially hydrolyzed during the gastric phase and had above 80% hydrolysis after duodenal digestion. There were no differences between the digestibility of goat milk and kefir (p > 0.05). Goat milk and kefir displayed about 7-fold antioxidant activity after digestion (p 0.05), however, after in vitro digestion calcium-binding capacity of the goat milk and kefir increased 2 and 5 fold, respectively (p < 0.05). Digested goat milk and kefir showed a higher dose-dependent inhibitory effect on α-amylase compared to undigested samples (p < 0.05). α-Glucosidase inhibitory activities and in vitro bile acid-binding capacities of the samples were not determined at the studied concentrations.

Social Problems Of Aged In A Rural Population

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Singh Charan

1995-01-01

Full Text Available Research Question: What are the social problems of aged persons in a rural population? Objectives: i To study social problems of aged. ii To identify measures to eliminate them. Study design: Cross- sectional. Setting: Rural areas of Machhra Rural Health & Training Centre attached with Deptt. of SPM, Medical College, Meerut. Participants: Population above 60 years of age. Sample Size: 1000 households from 5 villages, which had 464 participants. Study Variables: Chi- square test. Results: In all, 259 (55.8% aged persons were engaged in productive work while 205 (44.2% were not doing any productive work. Of 376 aged persons living in joint families, 207 (55% were being respected, 71(18.9% were indifferently treated and 98 (26.1% were being neglected by family members. Recommendations: It is a strong case for proper planning to improve the lot of old age population especially for their social problems at the earliest.

Anaerobic Digestion Assessment for Contingency Base Waste

Science.gov (United States)

2014-05-01

heating. The use of anaerobic digestion for high solids organic waste (15 to 50 percent solids; i.e., mixed organic solids, such as food waste, manure ...but the team was not able to identify any for anaerobic digestion . One potentially widespread source is manure from ruminant organisms, such as...plug-flow digesters treating swine manure and used cooking grease. Bioresource Technology 101:4362-4370. ERDC TR-14-3 63 Lansing, S., and A.R

The effects of digestion temperature and temperature shock on the biogas yields from the mesophilic anaerobic digestion of swine manure.

Science.gov (United States)

Chae, K J; Jang, Am; Yim, S K; Kim, In S

2008-01-01

In order to obtain basic design criteria for anaerobic digesters of swine manure, the effects of different digesting temperatures, temperature shocks and feed loads, on the biogas yields and methane content were evaluated. The digester temperatures were set at 25, 30 and 35 degrees C, with four feed loads of 5%, 10%, 20% and 40% (feed volume/digester volume). At a temperature of 30 degrees C, the methane yield was reduced by only 3% compared to 35 degrees C, while a 17.4% reduction was observed when the digestion was performed at 25 degrees C. Ultimate methane yields of 327, 389 and 403 mL CH(4)/g VS(added) were obtained at 25, 30 and 35 degrees C, respectively; with moderate feed loads from 5% to 20% (V/V). From the elemental analysis of swine manure, the theoretical biogas and methane yields at standard temperature and pressure were 1.12L biogas/g VS(destroyed) and 0.724 L CH(4)/g VS(destroyed), respectively. Also, the methane content increased with increasing digestion temperatures, but only to a small degree. Temperature shocks from 35 to 30 degrees C and again from 30 to 32 degrees C led to a decrease in the biogas production rate, but it rapidly resumed the value of the control reactor. In addition, no lasting damage was observed for the digestion performance, once it had recovered.

Exigências de lisina digestível para codornas japonesas na fase de postura Digestible lysine requirements for laying Japanese quails

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Fernando Guilherme Perazzo Costa

2008-12-01

Full Text Available Objetivou-se estimar as exigências nutricionais de lisina digestível para codornas japonesas em postura. Foram utilizadas 240 codornas distribuídas em delineamento de blocos casualizados, com cinco tratamentos, cada um com seis repetições de oito aves. Os tratamentos consistiram de uma ração basal deficiente em lisina e suplementada com L-lisina.HCL, de modo a apresentar 0,88; 0,96; 1,04; 1,12 ou 1,20% de lisina digestível. Avaliaram-se o consumo de ração (CR, a produção de ovos (PR, o peso (PO e a massa (MO do ovo, a conversão alimentar por massa (CMO e por dúzia (CDZ de ovos, os pesos de albúmen (PA, gema (PG e casca (PC, as porcentagens de albúmen (%A, gema (%G e casca (%C e a gravidade específica (GE dos ovos. O nível de lisina digestível da ração influenciou o consumo de ração, enquanto a produção de ovos respondeu de forma quadrática aos níveis de lisina. As demais variáveis analisadas não foram influenciadas pelo nível de lisina digestível da ração. A exigência de lisina digestível para codornas japonesas em postura foi estimada em 1,03% da ração, que corresponde a um consumo diário de 292 mg de lisina digestível.The objective was to estimate the nutritional requirements of digestible lysine for Japanese laying quails. Two hundred and forty Japanese quails were allotted to a completely randomized block designs, with five diets, with six replications of eight birds each. Diets consisted of a basal ration deficient in lysine and supplemented with five levels 0.88, 0.96, 1.04, 1.12 or 1.20% of digestible lysine. Feed consumption, egg production, egg weight and egg mass, feed conversion by egg mass (FCEM and by dozen egg were evaluated. It was also evaluated, albumen weight, yolk weight and shell weight, percentages of albumen, yolk and shell and egg specific gravity. Dietary digestible lysine level linearly influenced feed intake, while egg production was affected in a quadratic faction by digestible

Anaerobic Digestion Modeling: from One to Several Bacterial Populations

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Iván D. Ramírez-Rivas

2013-11-01

Full Text Available Anaerobic digestion systems are complex processes that unfortunately often suffer from instability causing digester failure. In order to be able to design, optimizing and operate efficiently anaerobic digestion systems, appropriate control strategies need to be designed. Such strategies require, in general, the development of mathematical models. The anaerobic digestion process comprises a complex network of sequential and parallel reactions of biochemical and physicochemical nature. Usually, such reactions contain a particular step, the so called rate-limiting step which, being the slowest, limits the reaction rate of the overall process. The first attempts for modeling anaerobic digestion led to models describing only the limiting step. However, over a wide range of operating conditions, the limiting step is not always the same. It may depend on wastewater characteristics, hydraulic loading, temperature, etc. It is apparent that the "limiting step hypothesis" leads to simple and readily usable models. Such models, however, do not describe very well the digester behavior, especially under transient operating conditions. This work reviews the current state-of-the-art in anaerobic digestion modeling. We give a brief description of the key anaerobic digestion models that have been developed so far for describing biomass growth systems, including the International Water Association’s Anaerobic Digestion Model 1 (ADM1 and we identify the areas that require further research endeavors.

The rural areas electrification with a hybrid photovoltaic systems

International Nuclear Information System (INIS)

Kocev, Kiril I.; Dimitrov, Dimitar; Tudzharov, Gjorgji

2001-01-01

Depending on a daily load demand, distance from the utility grid and the available solar energy, the rural villages electrification with a hybrid photovoltaic (PV) system can be a cheaper solution than the classic electrification, by connecting them to the utility grid. Besides PV generator, the considered hybrid system is consisted of a battery and a diesel gen set. For the concrete case - rural village with estimated daily load demand of 15.5 kWh/day, with the computer program PVFORM, which is modified for such hybrid system, were simulated a few hundreds PV systems, with different sizes of the PV generator and of the battery capacity. Analyzing the obtained results, it can be foreseen the influence of the component size on the system functionality. From the mass of possible system combinations, it is chosen one that has 42 % lower initial investment, than the initial investment for connection of the village to the utility grid. (Original)

Domestic solid waste and sewage improvement by anaerobic digestion: A stirred digester

Energy Technology Data Exchange (ETDEWEB)

Lebrato, J.; Perez-Rodriguez, J.L. [CSIC-UNSE, Instituto de Ciencia de Materiales, Sevilla (Spain); Maqueda, C. [CSIC Instituto de Recursos Naturales y Agrobiologia, Sevilla (Spain)

1995-05-01

The processing of the mixture of domestic solid waste and domestic sewage in an stirring digester was studied. The experimental set up consisted of six thermostatically controlled digesters of 1 l, each one in a bath at 35{+-}1oC and magnetically stirred. The best feeding for the culture was 1.7 g COD l{sup -1} day{sup -1}. The minimum hydraulic retention time was 6 days. The efficiency in COD removal of treatment varied between 90.1% and 72.4%. The biogas productivity was 0.19 l g{sup -1} COD day{sup -1}

Growth of Nile tilapia post-larvae from broodstock fed diet with different levels of digestible protein and digestible energy

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Silia Maria de Negreiros Sousa

2013-08-01

Full Text Available This study was carried out to evaluate the influence of different levels of digestible energy and digestible protein in diets of Nile tilapia (Oreochromis niloticus broodstock on offspring growth during sex reversal stage. A total of 2,700 post-larvae (8.2±0.001 mg derived from breeders fed nine diets with distinct levels of digestible protein (28, 34 and 40% DP and digestible energy (2,800; 3,400; and 4,000 kcal DE.kg-1 were stored in twenty-seven 70 L tanks. After 30 days of growth, their average final weight (AFW, g, average weight gain (AWG, g, final standard length (SL, cm, condition factor (CF, specific growth rate (SGR, %/day, stock uniformity (UNI, %, survival (SUR, % and sex reversal rate (SRR, % were measured. Although female nutrition is thought to influence the performance or quality of progeny during early life stages, no influence of diets supplied to broodstock was detected on any parameter. Nonetheless, the offspring presented commercially satisfactory growth rates. Thus, diets containing 28% of digestible protein and 2,800 kcal of digestible energy.kg of diet-1 can be used to feed Nile tilapia broodstock without jeopardizing offspring performance during the sex reversal phase.

United States Nuclear Regulatory Commission Staff Practice and Procedure Digest. Digest No. 2

International Nuclear Information System (INIS)

1978-08-01

This second edition of the NRC Staff Practice and Procedure Digest contains a digest of a number of Commission, Atomic Safety and Licensing Appeal Board and Atomic Safety and Licensing Board decisions issued during the period from July 1, 1972 to March 31, 1978 interpreting the NRC's Rules of Practice in 10 CFR Part 2. This second edition replaces the first edition and its supplements and includes appropriate changes reflecting the recent amendments to the Rules of Practice which became effective on May 26, 1978

Iron uptake by Caco-2 cells following in vitro digestion: effects of heat treatments of pork meat and pH of the digests.

Science.gov (United States)

Sørensen, Anne D; Bukhave, Klaus

2010-10-01

The present in vitro studies report on iron uptake by Caco-2 cells from pepsin and pepsin+pancreatin-digested pork meat proteins at pH values between 4.6 and 7 mimicking conditions in the duodenum and the proximal jejunum, respectively. Heat treatment of the pork meat resulted in increased iron uptake from pepsin-digested samples to Caco-2 cells at pH 4.6. The major enhancing effects on iron uptake by Caco-2 cells were observed after pepsin digestion in the pH range 4.6-6.0, whereas the pepsin+pancreatin-digested samples resulted in negligible iron uptake in Caco-2 cells at pH 7. Thus, the results emphasize the importance of separating pepsin-digested and pepsin+pancreatin-digested proteins during in vitro studies on iron availability. Furthermore, the present results showed the pH dependency of iron uptake anticipated. The enhancing effect of ascorbic acid was verified by increased iron uptake from pepsin-digested pork meat samples at pH 4.6, while no effect of ascorbic acid was observed at pH 7 in pepsin+pancreatin-digested samples. Copyright © 2010 Elsevier GmbH. All rights reserved.

Modified anaerobic digestion elutriated phased treatment for the anaerobic co-digestion of sewage sludge and food wastewater.

Science.gov (United States)

Mo, Kyung; Lee, Wonbae; Kim, Moonil

2017-02-01

A modified anaerobic digestion elutriated phased treatment (MADEPT) process was developed for investigating anaerobic co-digestion of sewage sludge and food wastewater. The anaerobic digestion elutriated phased treatment (ADEPT) process is similar to a two-phase system, however, in which the effluent from a methanogenic reactor recycles into an acidogenic reactor to elutriate mainly dissolved organics. Although ADEPT could reduce reactor volume significantly, the unsolubilized solids should be wasted from the system. The MADEPT process combines thermo-alkali solubilization with ADEPT to improve anaerobic performance and to minimize the sludge disposal. It was determined that the optimal volume mixing ratio of sewage sludge and food wastewater was 4 : 1 for the anaerobic co-digestion. The removal efficiencies of total chemical oxygen demand, volatile solids, and volatile suspended solids in the MADEPT process were 73%, 70%, and 64%, respectively. However, those in the ADEPT process were only 48%, 37%, and 40%, respectively, at the same hydraulic retention time (HRT) of 7 days. The gas production of MADEPT was two times higher than that of ADEPT. The thermo-alkali solubilization increased the concentration of dissolved organics so that they could be effectively degraded in a short HRT, implying that MADEPT could improve the performance of ADEPT in anaerobic co-digestion.

FEATURES DIGESTION OF STURGEON SPECIES (ACIPENSERIDAE (REVIEW

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M. Simon

2016-09-01

Full Text Available Purpose. To review scientific sources are about the anatomical, physiological and biochemical characteristics of the digestive system and proper digestion process in the sturgeon species (Acipenseridae. Outline the common anatomical and morphological characteristics of the gastrointestinal tract. Consider the activity of digestive enzymes and the influence of various factors. Findings. Review of scientific papers reveals that although the digestion of sturgeon are broadly similar to those of the cartilaginous and bony fish, there are a number of species specificity. In particular, sturgeon enzymes have a wider temperature and hydrogen ranges. It is confirmed that temperature adaptations of digestive system poikilothermic organ-isms are realised mainly thanks to reorganisations of fermental systems. It is shown that enzymes in sturgeons are adjustable, as their activity level significantly changes under the influence of divalent metal ions (Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+. The assumption that evolutionary adaptation of hydrolytic function of intestines of fishes to temperature conditions of an inhabitancy takes place, apparently, is made. The paper describes the effect of sex and age factors on the level of activity of enzymes of sturgeons. Set out the regularities of circadian rhythms of the fish of this family. Showed specific features of the liver and its involvement in lipid metabolism and antioxidant defense system. Practical value. The knowledge of hydrolysis characteristics of a diet of sturgeon species is important for the efficiency estimation of feeding and understanding of evolutionary and ecological aspects of digestion physiology. Systematized data on the digestive system of fish sturgeon species are of interest a wide range of research in two main areas. Firstly, although the sturgeon are relict species, but the adaptation of their digestive system is still going on, allowing you to analyze the evolutionary development of the

Caracterização do MP10 e MP2,5 e distribuição por tamanho de cloreto, nitrato e sulfato em atmosfera urbana e rural de Londrina Characterization of PM10 and PM2.5 and size distribution of chloride, nitrate and sulphate in urban and rural atmospheres of Londrina

Directory of Open Access Journals (Sweden)

Adriana de Marques Freitas

2009-01-01

Full Text Available Samplings of atmospheric particulate matter (PM were carried out between the months of March and April of 2007, simultaneously in two areas of Londrina, an urban (Historical Museum and other rural (Farm School-UEL. PM was collected using the cascade impactor consisting of four impaction stages (0.25 to 10 μm. The results indicated that the fine fraction (PM2.5 represented a significant portion of the mass of PM10 (70 and 67% in the urban and rural places, respectively. Cl-, NO3- and SO4(2- were determined by ion chromatography and the size distribution is presented. Natural and anthropogenic sources were suggested to the ionic components in the fine and coarse mode of PM.

Student Teachers' Ways of Thinking and Ways of Understanding Digestion and the Digestive System in Biology

Science.gov (United States)

Çimer, Sabiha Odabasi; Ursavas, Nazihan

2012-01-01

The purpose of this study was to identify the ways in which student teachers understand digestion and the digestive system and, subsequently, their ways of thinking, as reflected in their problem solving approaches and the justification schemes that they used to validate their claims. For this purpose, clinical interviews were conducted with 10…

Formation of reactive aldehydes (MDA, HHE, HNE) during the digestion of cod liver oil: comparison of human and porcine in vitro digestion models.

Science.gov (United States)

Tullberg, Cecilia; Larsson, Karin; Carlsson, Nils-Gunnar; Comi, Irene; Scheers, Nathalie; Vegarud, Gerd; Undeland, Ingrid

2016-03-01

In this work, we investigated lipid oxidation of cod liver oil during gastrointestinal (GI) digestion using two types of in vitro digestion models. In the first type of model, we used human GI juices, while we used digestive enzymes and bile from porcine origin in the second type of model. Human and porcine models were matched with respect to factors important for lipolysis, using a standardized digestion protocol. The digests were analysed for reactive oxidation products: malondialdehyde (MDA), 4-hydroxy-trans-2-nonenal (HNE), and 4-hydroxy-trans-2-hexenal (HHE) by liquid chromatography/atmospheric pressure chemical ionization-mass spectrometry (LC/APCI-MS), and for free fatty acids (FFA) obtained during the digestion by gas chromatography-mass spectrometry (GC-MS). The formation of the oxidation products MDA, HHE, and HNE was low during the gastric digestion, however, it increased during the duodenal digestion. The formation of the oxidation products reached higher levels when digestive juices of human origin were used (60 μM of MDA, 0.96 μM of HHE, and 1.6 μM of HNE) compared to when using enzymes and bile of porcine origin (9.8, and 0.36 μM of MDA; 0.16, and 0.026 μM of HHE; 0.23, and 0.005 μM of HNE, respectively, in porcine models I and II). In all models, FFA release was only detected during the intestinal step, and reached up to 31% of total fatty acids (FA). The findings in this work may be of importance when designing oxidation oriented lipid digestion studies.

Has Rural Banking Developed Rural Nigeria? | Amadasu | African ...

African Journals Online (AJOL)

There is problem of rural development in Nigeria because of increasing poverty in the rural areas where about 70% of the people live. Reducing poverty means increasing income. Increasing income means increasing bank loans and advances for efficient application to agricultural and industrial activities in the rural Nigeria ...

Biochemical, transcriptomic and proteomic analyses of digestion in the scorpion Tityus serrulatus: insights into function and evolution of digestion in an ancient arthropod.

Science.gov (United States)

Fuzita, Felipe J; Pinkse, Martijn W H; Patane, José S L; Juliano, Maria A; Verhaert, Peter D E M; Lopes, Adriana R

2015-01-01

Scorpions are among the oldest terrestrial arthropods and they have passed through small morphological changes during their evolutionary history on land. They are efficient predators capable of capturing and consuming large preys and due to envenomation these animals can become a human health challenge. Understanding the physiology of scorpions can not only lead to evolutionary insights but also is a crucial step in the development of control strategies. However, the digestive process in scorpions has been scarcely studied. In this work, we describe the combinatory use of next generation sequencing, proteomic analysis and biochemical assays in order to investigate the digestive process in the yellow scorpion Tityus serrulatus, mainly focusing in the initial protein digestion. The transcriptome generated database allowed the quantitative identification by mass spectrometry of different enzymes and proteins involved in digestion. All the results suggested that cysteine cathepsins play an important role in protein digestion. Two digestive cysteine cathepsins were isolated and characterized presenting acidic characteristics (pH optima and stability), zymogen conversion to the mature form after acidic activation and a cross-class inhibition by pepstatin. A more elucidative picture of the molecular mechanism of digestion in a scorpion was proposed based on our results from Tityus serrulatus. The midgut and midgut glands (MMG) are composed by secretory and digestive cells. In fasting animals, the secretory granules are ready for the next predation event, containing enzymes needed for alkaline extra-oral digestion which will compose the digestive fluid, such as trypsins, astacins and chitinase. The digestive vacuoles are filled with an acidic proteolytic cocktail to the intracellular digestion composed by cathepsins L, B, F, D and legumain. Other proteins as lipases, carbohydrases, ctenitoxins and a chitolectin with a perithrophin domain were also detected. Evolutionarily

Gastrointestinal physiology and digestive disorders in sleep.

Science.gov (United States)

Kanaly, Travis; Shaheen, Nicholas J; Vaughn, Bradley V

2009-11-01

The dynamic interplay of the digestive system and sleep is an excellent example of brain-body interaction. New advances in measuring techniques provide an opportunity to evaluate physiology that is dependent upon the sleep/wake state or circadian rhythm and potentially differentiate between normal and pathological conditions. Sleep-related changes in gastrointestinal physiology create vulnerabilities to digestive issues such as reflux, whereas disorders such as duodenal ulcers raise the importance of circadian variations in digestive system function. Advances in the area of normal sleep physiology have furthered our understanding of the underlying cause of irritable bowel syndrome, and the mechanisms by which sleep disruption may aggravate inflammatory bowel disease. Additionally, important early work has shown that the treatment of digestive disorders such as reflux can improve sleep quality just as the improvement in sleep may aid in the treatment of digestive disorders. For the clinician, these forward steps in our knowledge mark the start of an era in which understanding the effects of the sleep/wake state and circadian rhythms on gastrointestinal physiology promise to yield novel diagnostic and therapeutic opportunities.

Design and Fabrication of an Anaerobic Digester

Directory of Open Access Journals (Sweden)

M. S. Abubakar

2017-02-01

Full Text Available Anaerobic digester is a physical structure that provides a conducive environment for the multiplication of micro-organisms that degrades organic matter to generate biogas energy. Energy is required in agriculture for crop production, processing and storage, poultry production and electricity for farmstead and farm settlements. It is energy that propels agricultural mechanization, which minimizes the use of human and animal muscles and its inherent drudgery in agriculture. The energy demand required to meet up with the agricultural growth in Nigeria is high and growing every year. In this study the design and fabrication of an anaerobic digester was reported which is an attempt to boost energy requirement for small and medium dryland farmers in Nigeria. The design of the digester includes the following concept; the basic principles of anaerobic digestion processes, socio-economic status of the dryland farmers, amount of biogas to be produced. Finally, the digester was fabricated using locally available raw materials within the dryland area of Nigeria. At the end, preliminary flammability test was conducted and the biogas produced was found to be flammable.

Biogas/photovoltaic hybrid power system for decentralized energy supply of rural areas

International Nuclear Information System (INIS)

Borges Neto, M.R.; Carvalho, P.C.M.; Carioca, J.O.B.; Canafistula, F.J.F.

2010-01-01

Biomasses created from natural resources such as firewood, charcoal and forest crops are still the main source of energy in many communities in the developing countries of the world. The absence of modern techniques, in terms of energy conversion and the lack of resource planning, places a great burden on the environment, not only in terms of deforestation but the polluting residual emissions created by the burning of such fuels. Even in some developed countries, it is possible to find rural areas that have no access to the conventional national electrical grid. The lack of this facility is detrimental to the social and economic development of any country or community. Renewable energy systems have been used in many cases to mitigate these problems. The present paper introduces the concept of an alternative Hybrid Power System configuration that combines photovoltaic modules and digesters fuelled by goat manure as the basis for rural sustainable development. Attention is drawn to the Northeast Region of Brazil, one of the largest semi-arid regions in a single country. The regional conditions of Northeast of Brazil are not unique, suggesting that other countries of a similar nature would benefit from the same energy system.

Biogas/photovoltaic hybrid power system for decentralized energy supply of rural areas

Energy Technology Data Exchange (ETDEWEB)

Borges Neto, M.R. [Federal Institute of Education, Science and Technology of Sertao Pernambucano - IFSertao-PE, BR407, km 8, 56314-520 Petrolina, PE (Brazil); Federal University of Ceara, Department of Electrical Engineering, Caixa Postal 6001 - Campus do Pici, 60455-760 Fortaleza, CE (Brazil); Carvalho, P.C.M. [Federal University of Ceara, Department of Electrical Engineering, Caixa Postal 6001 - Campus do Pici, 60455-760 Fortaleza, CE (Brazil); Carioca, J.O.B. [Federal University of Ceara, Department of Food Engineering, Caixa Postal 6001 - Campus do Pici, 60455-760 Fortaleza, CE (Brazil); Canafistula, F.J.F. [Federal University of Ceara, Department of Agricultural Engineering, Caixa Postal 6001 - Campus do Pici, 60455-760 Fortaleza, CE (Brazil)

2010-08-15

Biomasses created from natural resources such as firewood, charcoal and forest crops are still the main source of energy in many communities in the developing countries of the world. The absence of modern techniques, in terms of energy conversion and the lack of resource planning, places a great burden on the environment, not only in terms of deforestation but the polluting residual emissions created by the burning of such fuels. Even in some developed countries, it is possible to find rural areas that have no access to the conventional national electrical grid. The lack of this facility is detrimental to the social and economic development of any country or community. Renewable energy systems have been used in many cases to mitigate these problems. The present paper introduces the concept of an alternative Hybrid Power System configuration that combines photovoltaic modules and digesters fuelled by goat manure as the basis for rural sustainable development. Attention is drawn to the Northeast Region of Brazil, one of the largest semi-arid regions in a single country. The regional conditions of Northeast of Brazil are not unique, suggesting that other countries of a similar nature would benefit from the same energy system. (author)

De-agrarianisation and rural employment in Igboland, south-eastern Nigeria

NARCIS (Netherlands)

Chukwuezi, B.

1999-01-01

This working paper provides research findings emanating from the De-Agrarianisation and Rural Employment (DARE) Research Programme, coordinated by the African Studies Centre, Leiden. The aim of the Programme was to examine, from a multidisciplinary perspective, the changes in size and significance

Effect of Recycle Sludge on Anaerobic Digestion of Palm Oil Mill Effluent in A Thermophilic Continuous Digester

Science.gov (United States)

Irvan; Trisakti, B.; Tomiuchi, Y.; Harahap, U.; Daimon, H.

2017-06-01

The objective of this research is to maintain short retention time and high degradation of palm oil mill effluent (POME) to biogas by applying recycle sludge. Fresh POME from Rambutan Mill without further treatment was used as feed. Two lab-scale digesters supported from Metawater Co. Ltd. have been applied to treat POME at thermophilic (55°C) condition. Both digesters were operated under intermittent operation mode. Experiments were performed in two methods: with and without recycle sludge. Hydraulic retention time (HRT) of both methods was maintained at 6 days, while sludge retention time (SRT) was maintained at various days. The result showed that by extending SRT in return sludge process where 25% of digested slurry recycled to the digester, improvement of volatile solid (VS) decomposition was obtained around 84% at HRT of 6 days and SRT of 21 days. Then, chemical oxygen demand (COD) removal efficiency could be reached until 85% by using recycle sludge.

EFFECT OF MALTING ON PROTEIN DIGESTIBILITY OF SOME ...

African Journals Online (AJOL)

Protein digestibility of sorghum is generally low. Malting is one of the processing methods which can be applied to improve this digestibility. It is a method whose technology is well known by local communities in Kenya. The objective of this study was to investigate the effect of malting on the digestibility of some varieties of ...

Community participation in rural health: a scoping review

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Kenny Amanda

2013-02-01

Full Text Available Abstract Background Major health inequities between urban and rural populations have resulted in rural health as a reform priority across a number of countries. However, while there is some commonality between rural areas, there is increasing recognition that a one size fits all approach to rural health is ineffective as it fails to align healthcare with local population need. Community participation is proposed as a strategy to engage communities in developing locally responsive healthcare. Current policy in several countries reflects a desire for meaningful, high level community participation, similar to Arnstein’s definition of citizen power. There is a significant gap in understanding how higher level community participation is best enacted in the rural context. The aim of our study was to identify examples, in the international literature, of higher level community participation in rural healthcare. Methods A scoping review was designed to map the existing evidence base on higher level community participation in rural healthcare planning, design, management and evaluation. Key search terms were developed and mapped. Selected databases and internet search engines were used that identified 99 relevant studies. Results We identified six articles that most closely demonstrated higher level community participation; Arnstein’s notion of citizen power. While the identified studies reflected key elements for effective higher level participation, little detail was provided about how groups were established and how the community was represented. The need for strong partnerships was reiterated, with some studies identifying the impact of relational interactions and social ties. In all studies, outcomes from community participation were not rigorously measured. Conclusions In an environment characterised by increasing interest in community participation in healthcare, greater understanding of the purpose, process and outcomes is a priority for

Techno-economic evaluation of masonry type animal feed solar cooker in rural areas of an Indian state Rajasthan

International Nuclear Information System (INIS)

Panwar, N.L.; Kothari, Surendra; Kaushik, S.C.

2013-01-01

Utilisation of animal draft power in agricultural operation and milk production is highly dependent on the feed and fodder. Properly cooked feed is digestive in nature and enhance milk production. Solar energy is promising option for slow cooking. Keeping this in view a masonry animal feed solar cooker (AFSC) was developed. It helps in the number of ways to improve the living standard of rural farmers and also reduce the CO 2 emission by replacing conventional fossil fuel. The AFSC can replace the 100 per cent biomass and save about 424.80 kg of CO 2 on annual basis and save about 24 INR per day. Usually women prepare animal feed in rural areas, hence cooking with AFSC save time and this time can be spear to take care of her family or in agricultural operation. This paper presents fuel replacement and reduction of carbon dioxide on annual basis and economic evaluation of AFSC. - Highlights: ► Considerable amount of energy can be saved on annual basis. ► This also helps to save the time and money of rural farmer. ► AFSC helps to reduce the greenhouse gas.

The influencing factors of energy poverty in rural Cameroon; Les determinants de la pauvrete energetique en milieu rural au Cameroun

Energy Technology Data Exchange (ETDEWEB)

Kamdem, Maxime; Edzengte, Joseph

2010-09-15

The objective of this study is to assess the influencing factors of energy poverty in rural Cameroon. The method used is in two stages: the first stage is a statistical analysis that has allowed to determine the level of energy poverty in rural areas, which is 7.5%. The second stage assesses the influencing factors of this poverty type. The results show that the revenue impacts on energy poverty, as well as the size of the household, in which the arrival of an additional person increases by 1.16% the chances that the household will suffer from energy poverty. [French] L'objectif de cette etude est d'evaluer les determinants de la pauvrete energetique en milieu rural au Cameroun. La methode mise en oeuvre procede en deux etapes : la premiere est une analyse statistique qui a permis de determiner le seuil de pauvrete energetique en milieu rural, qui se situe a 7,5%. La deuxieme etape evalue les determinants de ce type de pauvrete. Les resultats indiquent que le revenu explique la pauvrete energetique, de meme que la taille du menage dont l'arrivee d'une personne supplementaire accroit de 1,16% les chances de ce menage d'etre pauvre sur le plan energetique.

Results of a survey to determine demographic and business management factors associated with size and growth rate of rural mixed-animal veterinary practices.

Science.gov (United States)

Brusk, Amy M; White, Brad J; Goehl, Dan R; Dhuyvetter, Kevin C

2010-12-15

To determine potential associations between demographic and business management factors and practice size and growth rate in rural mixed-animal veterinary practices. Cross-sectional survey. 54 mixed-animal practitioners. A cross-sectional survey (96 questions) was electronically disseminated. Responses were collected, and outcomes (number of veterinarians [NV], growth in number of veterinarians [NVG], gross practice income [GPI], growth in gross practice income [GPIG], gross practice income per veterinarian [GPIV], and growth in gross practice income per veterinarian [GPIVG]) were calculated. Bivariate analyses were performed and multivariable models created to determine associations between survey responses and outcomes of interest. Survey respondents were from mixed-animal practices, and most (46/54 [85.2%]) practiced in small communities (business manager. Typically, practices had positive mean growth in NVG (4.4%), GPIG (8.5%), and GPIVG (8.1%), but growth rate was highly variable among practices. Factors associated with growth rate included main species interest, frequency for adjusting prices, use of a marketing plan, service fee structure, and sending a client newsletter. Mixed-animal practices had a large range in size and growth rate. Economic indices were impacted by common business management practices.

Influence of barley grain particle size and treatment with citric acid on digestibility, ruminal fermentation and microbial protein synthesis in Holstein calves.

Science.gov (United States)

Kazemi-Bonchenari, M; Salem, A Z M; López, S

2017-08-01

Chemical and physical treatments of barley grain increase ruminally resistant starch and can improve the rumen fermentation pattern. The objective of the present study was to evaluate the effects of chemical (addition of citric acid, CA) and physical (grinding to two different particle sizes, PS) treatment of barley grain on performance, rumen fermentation, microbial protein yield in the rumen and selected blood metabolites in growing calves. In all, 28 male Holstein calves (172±5.1 kg initial BW) were used in a complete randomised design with a factorial arrangement of 2 barley grain particle sizes×2 levels of citric acid. The diets were as follows: (i) small PS (average 1200 µm) barley grain soaked in water (no CA addition); (ii) small PS barley grain soaked in a CA solution (adding 20 g CA/kg barley); (iii) large PS (average 2400 µm) barley grain soaked in water (no citric acid addition) and (iv) large PS barley grain soaked in a citric acid solution (adding 20 g CA/kg barley). Barley grain was then incorporated at 35% in a total mixed ration and fed to the calves for 11 weeks. Feeding small PS barley decreased feed intake (P=0.02) and average daily weight gain (P=0.01). The addition of CA to barley grain did not affect intake but increased weight gain (P0.05). However, the molar proportion of propionate was increased (P=0.03) when barley was more finely ground, and that of acetate was increased (P=0.04) when CA was added to barley grain. The ruminal concentration of ammonia nitrogen was increased (Pgrain with citric acid increased fibre digestibility of total mixed rations, attenuated the decrease in ruminal pH, and improved weight gain and feed efficiency in male Holstein growing calves fed a high-cereal diet (550 g cereal grain/kg diet).

Are carnivore digestive separation mechanisms revealed on structure-rich diets?: Faecal inconsistency in dogs (Canis familiaris fed day old chicks.

Directory of Open Access Journals (Sweden)

Annelies De Cuyper

Full Text Available Pronounced variations in faecal consistency have been described anecdotally for some carnivore species fed a structure-rich diet. Typically two faecal consistencies are distinguished, namely hard and firm versus liquid and viscous faeces. It is possible that a separation mechanism is operating in the carnivore digestive tract, as in many herbivore species. Six beagle dogs were fed two experimental diets in a cross-over design of 7 days. Test diets consisted of chunked day old chicks differing only in particle size (fine = 7.8 mm vs coarse = 13 mm in order to vary dietary structure. Digestive retention time was measured using titanium oxide (TiO2 as marker. The total faecal output was scored for consistency and faecal fermentation profiles were evaluated through faecal short-chain fatty acid (SCFA and ammonia (NH3 analyses. A total of 181 faecal samples were collected. Dietary particle size did not affect faecal consistency, fermentative end products nor mean retention time (MRT. However, a faecal consistency dichotomy was observed with firm faeces (score 2-2.5 and soft faeces (score 4-4.5 being the most frequently occurring consistencies in an almost alternating pattern in every single dog. Firm and soft faeces differed distinctively in fermentative profiles. Although the structure difference between diets did not affect the faecal dichotomy, feeding whole prey provoked the occurrence of the latter which raises suspicion of a digestive separation mechanism in the canine digestive tract. Further faecal characterisation is however required in order to unravel the underlying mechanism.

Characterization of Spartina alterniflora as feedstock for anaerobic digestion

International Nuclear Information System (INIS)

Yang, Shiguan; Zheng, Zheng; Meng, Zhuo; Li, Jihong

2009-01-01

Smooth cordgrass (Spartina alterniflora), a saltmarsh plant with high production, was characterized for its potential for use as feedstock for anaerobic digestion processes. The anaerobic digestibility and biogas yield of S. alterniflora were evaluated by anaerobic batch digestion experiments performed at 35 ± 1 C at initial volatile solids (VS) of 6%. The nutrient content analysis indicated that S. alterniflora contained the required nutrition for anaerobic microorganisms, but its high C/N of 58.8, high K and Na contents of 8.1, 22.7 g kg -1 , respectively, may be disadvantageous to its anaerobic digestion. The cumulative biogas yield was determined to be 358 L kg -1 VS and the biodegradation efficiency was 45% after 60 days of digestion. The methane content of biogas increased from 53% on day 3 to around 62% after 13 days of digestion. The changes of volatile fatty acids (VFAs) indicated that the acidification of S. alterniflora was propionate-type fermentation with proportion of acetate and propionate ranging from 54.8% to 98.4%, and the hydrolysis of lignocellulose was the rate-limiting step for its anaerobic digestion. The analysis of cations suggested that K + and Mg 2+ , with the maximum concentration of 1.35 and 0.43 g L -1 in fermentation liquor, respectively, could be inhibitory to the anaerobic digestion of S. alterniflora. It is concluded that S. alterniflora can be transformed into clean energy by anaerobic digestion and the high contents of K, Na, Ca and Mg may be the inhibitory factors when S. alterniflora is digested by continuous or semi-continuous anaerobic process. (author)

Time trends and determinants of completed family size in a rural community from the Basque area of Spain (1800-1969).

Science.gov (United States)

Alfonso-Sánchez, Miguel A; Peña, José A; Calderón, Rosario

2003-10-01

The focus of this work is the analysis of changes in completed family size and possible determinants of that size over time, in an attempt to characterize the evolution of reproductive patterns during the demographic transition. With this purpose in mind, time trends are studied in relation to the mean number of live births per family (as an indirect measure of fertility), using family reconstitution techniques to trace the reproductive history of each married woman. The population surveyed is a Spanish rural community called Lanciego, located at the southern end of the province of Alava (Basque Country). A total of 24,510 parish records of baptisms, marriages and burials made between 1800 and 1969 were examined to obtain the demographic data set. For each reconstituted family, the variables included in the study were the number of live births per family or family size (FAMS), year of marriage (YEAR), age at marriage of both partners (AMAN, AWOM), wife's age at the end of marriage (WEND), duration of marriage (MARD), age at first maternity (A1CH), length of reproductive span (REPS) and number of children dying before their first anniversary (MINF). Through a principal component analysis, three factors were found that explained more than 75% of the total variance. Association of variables in factors I and III was particularly useful in characterizing the variability of mean family size in pre-transitional, transitional and post-transitional cohorts. During demographic transition, a decreasing trend is observed in the variables FAMS, REPS and MINF, while variables AWOM, AMAN, WEND and A1CH show a tendency to increase over the 20th century. Results obtained by multiple regression analysis confirm that the best predictors of family size (dependent variable) were REPS and MINF, which between them explained over 85% of the total variation in FAMS (R2 = 0.853). In Lanciego, birth control seems to be present on the evidence of an increase in age at first maternity and a

Optimal location of centralized biodigesters for small dairy farms: A case study from the United States

Directory of Open Access Journals (Sweden)

Deep Mukherjee

2015-06-01

Full Text Available Anaerobic digestion technology is available for converting livestock waste to bio-energy, but its potential is far from fully exploited in the United States because the technology has a scale effect. Utilization of the centralized anaerobic digester (CAD concept could make the technology economically feasible for smaller dairy farms. An interdisciplinary methodology to determine the cost minimizing location, size, and number of CAD facilities in a rural dairy region with mostly small farms is described. This study employs land suitability analysis, operations research model and Geographical Information System (GIS tools to evaluate the environmental, social, and economic constraints in selecting appropriate sites for CADs in Windham County, Connecticut. Results indicate that overall costs are lower if the CADs are of larger size and are smaller in number.

Horse manure as feedstock for anaerobic digestion.

Science.gov (United States)

Hadin, Sa; Eriksson, Ola

2016-10-01

Horse keeping is of great economic, social and environmental benefit for society, but causes environmental impacts throughout the whole chain from feed production to manure treatment. According to national statistics, the number of horses in Sweden is continually increasing and is currently approximately 360,000. This in turn leads to increasing amounts of horse manure that have to be managed and treated. Current practices could cause local and global environmental impacts due to poor performance or lack of proper management. Horse manure with its content of nutrients and organic material can however contribute to fertilisation of arable land and recovery of renewable energy following anaerobic digestion. At present anaerobic digestion of horse manure is not a common treatment. In this paper the potential for producing biogas and biofertiliser from horse manure is analysed based on a thorough literature review in combination with mathematical modelling and simulations. Anaerobic digestion was chosen as it has a high degree of resource conservation, both in terms of energy (biogas) and nutrients (digestate). Important factors regarding manure characteristics and operating factors in the biogas plant are identified. Two crucial factors are the type and amount of bedding material used, which has strong implications for feedstock characteristics, and the type of digestion method applied (dry or wet process). Straw and waste paper are identified as the best materials in an energy point of view. While the specific methane yield decreases with a high amount of bedding, the bedding material still makes a positive contribution to the energy balance. Thermophilic digestion increases the methane generation rate and yield, compared with mesophilic digestion, but the total effect is negligible. Copyright © 2016. Published by Elsevier Ltd.

Contamination and source differentiation of Pb in park soils along an urban-rural gradient in Shanghai

International Nuclear Information System (INIS)

Li Hongbo; Yu Shen; Li Guilin; Deng Hong; Luo Xiaosan

2011-01-01

Urban soil Pb contamination is a great human health risk. Lead distribution and source in topsoils from 14 parks in Shanghai, China were investigated along an urban-rural gradient. Topsoils were contaminated averagely with 65 mg Pb kg -1 , 2.5 times higher than local soil background concentrations. HCl-extracts contained more anthropogenic Pb signatures than total sample digests as revealed by the higher 207/206 Pb and 208/206 Pb ratios in extracts (0.8613 ± 0.0094 and 2.1085 ± 0.0121 versus total digests 0.8575 ± 0.0098 and 2.0959 ± 0.0116). This suggests a higher sensitivity of HCl-extraction than total digestion in identifying anthropogenic Pb sources. Coal combustion emission was identified as the major anthropogenic Pb source (averagely 47%) while leaded gasoline emission contributed 12% overall. Urbanization effects were observed by total Pb content and anthropogenic Pb contribution. This study suggests that to reduce Pb contamination, Shanghai might have to change its energy composition to clean energy. - Highlights: → Coal combustion emission is identified as a main Pb source in Shanghai park soils. → HCl-extraction is sensitive in identifying anthropogenic isotope Pb sources. → Soil Pb contamination and its anthropogenic sources showed urbanization effects. - Coal combustion emission was identified as the main anthropogenic source of soil Pb contamination affecting Shanghai parks.

Simulating Dinosaur Digestion in the Classroom.

Science.gov (United States)

Peczkis, Jan

1992-01-01

Describes an activity for use with a chapter on dinosaurs, prehistoric life, or digestion in which children make simulated dinosaur stomachs to gain hands-on experience about the theory of gastroliths, or stomach stones. Presents teacher information about the digestive processes in birds and dinosaurs. Discusses materials needed, objectives,…

Steam Digest 2001

Energy Technology Data Exchange (ETDEWEB)

2002-01-01

Steam Digest 2001 chronicles BestPractices Program's contributions to the industrial trade press for 2001, and presents articles that cover technical, financial and managerial aspects of steam optimization.

The impact of micro financing on poverty levels of rural women farm households in Abia state, Nigeria; implication for policy intervention

Directory of Open Access Journals (Sweden)

EZEH Innocent

2013-06-01

Full Text Available This study determined the impact of micro-finance on poverty level of rural women farm households in Abia State, Nigeria: Implication for policy intervention. A multi-stage random sampling technique was used to +select the local government areas, communities and respondents in the three (Aba, Ohafia and Umuahia agricultural zones of the State. The sample size was 240 (120 a piece for rural women farmer borrowers and non borrowers. Instrument of data collection was a set of structured and pre-tested questionnaire administered on both groups of rural women farmers. The result indicated that incidence of poverty or head count ratio was 0.558 for the rural women farmers borrowers and 0.933 for the rural women farmer non borrowers; poverty gap otherwise known as income short fall was 0.4547 for the rural women farmer borrowers and 0.6995 for the rural women farmer non borrowers. The result of the paired t-test showed that micro-finance impacted significantly on annual farm income, farm size and fertilizer use level of rural women farmer borrowers at given levels of significance. It was however, recommended that increased subsidy policy on agro-inputs and increased funding by the micro-finance will significantly aim at reducing the poverty levels of these women.