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Sample records for digestive tractus implication

  1. Tractus Catena Collapse Pits

    NASA Technical Reports Server (NTRS)

    2004-01-01

    [figure removed for brevity, see original site]

    We will be looking at collapse pits for the next two weeks. Collapse pits on Mars are formed in several ways. In volcanic areas, channelized lava flows can form roofs which insulate the flowing lava. These features are termed lava tubes on Earth and are common features in basaltic flows. After the lava has drained, parts of the roof of the tube will collapse under its own weight. These collapse pits will only be as deep as the bottom of the original lava tube. Another type of collapse feature associated with volcanic areas arises when very large eruptions completely evacuate the magma chamber beneath the volcano. The weight of the volcano will cause the entire edifice to subside into the void space below it. Structural features including fractures and graben will form during the subsidence. Many times collapse pits will form within the graben. In addition to volcanic collapse pits, Mars has many collapse pits formed when volatiles (such as subsurface ice) are released from the surface layers. As the volatiles leave, the weight of the surrounding rock causes collapse pits to form.

    These collapse pits are found in graben located in Tractus Catena. These features are related to subsidence after magma chamber evacuation of Alba Patera.

    Image information: VIS instrument. Latitude 35.8, Longitude 241.7 East (118.3 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA

  2. [Immune response and digestive cancers: Prognostic and therapeutic implications].

    PubMed

    Bibeau, Frédéric; Bazille, Céline; Svrcek, Magali; Pierson, Rémi; Lagorce-Pagès, Christine; Cohen, Romain; André, Thierry

    2017-02-01

    The aim of this article is to emphasize the impact of the immune response in digestive cancers, especially from colorectal (CRC) origin. In this setting, an adaptive lymphocytic infiltrate underlines the prognostic impact of the immune response, because it is associated to a favorable outcome. The next challenge will be to validate, in a prospective therapeutic trial, the integration of the immune response as decisional parameter for adjuvant therapy. The immune response is also a predictive parameter in microsatellite instable metastatic CRC, characterized by an adaptive lymphocytic infiltrate, leading to a very high response rate to immune therapies. However, prognostic and predictive biomarkers still need to be optimized in order to better select patients. These data are also valuable for digestive non-colorectal cancers, which are briefly analyzed. The methodology for the assessment of these prognostic and predictive biomarkers, which represents an important issue in precision medicine, is also discussed.

  3. HER2 aberrations and heterogeneity in cancers of the digestive system: Implications for pathologists and gastroenterologists

    PubMed Central

    Fusco, Nicola; Bosari, Silvano

    2016-01-01

    Management of cancers of the digestive system has progressed rapidly into the molecular era. Despite the significant recent achievements in the diagnosis and treatment of these patients, the number of deaths for these tumors has currently plateaued. Many investigations have assessed the role of HER2 in tumors of the digestive system in both prognostic and therapeutic settings, with heterogeneous results. Novel testing and treatment guidelines are emerging, in particular in gastric and colorectal cancers. However, further advances are needed. In this review we provide a comprehensive overview of the current state-of-knowledge of HER2 alterations in the most common tumors of the digestive system and discuss the operational implications of HER2 testing. PMID:27672288

  4. Glucose sensing by GABAergic neurons in the mouse nucleus tractus solitarii

    PubMed Central

    Boychuk, Carie R.; Gyarmati, Peter; Xu, Hong

    2015-01-01

    Changes in blood glucose concentration alter autonomic function in a manner consistent with altered neural activity in brain regions controlling digestive processes, including neurons in the brain stem nucleus tractus solitarii (NTS), which process viscerosensory information. With whole cell or on-cell patch-clamp recordings, responses to elevating glucose concentration from 2.5 to 15 mM were assessed in identified GABAergic NTS neurons in slices from transgenic mice that express EGFP in a subset of GABA neurons. Single-cell real-time RT-PCR was also performed to detect glutamic acid decarboxylase (GAD67) in recorded neurons. In most identified GABA neurons (73%), elevating glucose concentration from 2.5 to 15 mM resulted in either increased (40%) or decreased (33%) neuronal excitability, reflected by altered membrane potential and/or action potential firing. Effects on membrane potential were maintained when action potentials or fast synaptic inputs were blocked, suggesting direct glucose sensing by GABA neurons. Glucose-inhibited GABA neurons were found predominantly in the lateral NTS, whereas glucose-excited cells were mainly in the medial NTS, suggesting regional segregation of responses. Responses were prevented in the presence of glucosamine, a glucokinase (GCK) inhibitor. Depolarizing responses were prevented when KATP channel activity was blocked with tolbutamide. Whereas effects on synaptic input to identified GABAergic neurons were variable in GABA neurons, elevating glucose increased glutamate release subsequent to stimulation of tractus solitarius in unlabeled, unidentified neurons. These results indicate that GABAergic NTS neurons act as GCK-dependent glucose sensors in the vagal complex, providing a means of modulating central autonomic signals when glucose is elevated. PMID:26084907

  5. Glucose sensing by GABAergic neurons in the mouse nucleus tractus solitarii.

    PubMed

    Boychuk, Carie R; Gyarmati, Peter; Xu, Hong; Smith, Bret N

    2015-08-01

    Changes in blood glucose concentration alter autonomic function in a manner consistent with altered neural activity in brain regions controlling digestive processes, including neurons in the brain stem nucleus tractus solitarii (NTS), which process viscerosensory information. With whole cell or on-cell patch-clamp recordings, responses to elevating glucose concentration from 2.5 to 15 mM were assessed in identified GABAergic NTS neurons in slices from transgenic mice that express EGFP in a subset of GABA neurons. Single-cell real-time RT-PCR was also performed to detect glutamic acid decarboxylase (GAD67) in recorded neurons. In most identified GABA neurons (73%), elevating glucose concentration from 2.5 to 15 mM resulted in either increased (40%) or decreased (33%) neuronal excitability, reflected by altered membrane potential and/or action potential firing. Effects on membrane potential were maintained when action potentials or fast synaptic inputs were blocked, suggesting direct glucose sensing by GABA neurons. Glucose-inhibited GABA neurons were found predominantly in the lateral NTS, whereas glucose-excited cells were mainly in the medial NTS, suggesting regional segregation of responses. Responses were prevented in the presence of glucosamine, a glucokinase (GCK) inhibitor. Depolarizing responses were prevented when KATP channel activity was blocked with tolbutamide. Whereas effects on synaptic input to identified GABAergic neurons were variable in GABA neurons, elevating glucose increased glutamate release subsequent to stimulation of tractus solitarius in unlabeled, unidentified neurons. These results indicate that GABAergic NTS neurons act as GCK-dependent glucose sensors in the vagal complex, providing a means of modulating central autonomic signals when glucose is elevated.

  6. Baroreflex failure in a patient with central nervous system lesions involving the nucleus tractus solitarii

    NASA Technical Reports Server (NTRS)

    Biaggioni, I.; Whetsell, W. O.; Jobe, J.; Nadeau, J. H.

    1994-01-01

    Animal studies have shown the importance of the nucleus tractus solitarii, a collection of neurons in the brain stem, in the acute regulation of blood pressure. Impulses arising from the carotid and aortic baroreceptors converge in this center, where the first synapse of the baroreflex is located. Stimulation of the nucleus tractus solitarii provides an inhibitory signal to other brain stem structures, particularly the rostral ventrolateral medulla, resulting in a reduction in sympathetic outflow and a decrease in blood pressure. Conversely, experimental lesions of the nucleus tractus solitarii lead to loss of baroreflex control of blood pressure, sympathetic activation, and severe hypertension in animals. In humans, baroreflex failure due to deafferentation of baroreceptors has been previously reported and is characterized by episodes of severe hypertension and tachycardia. We present a patient with an undetermined process of the central nervous system characterized pathologically by ubiquitous infarctions that were particularly prominent in the nucleus tractus solitarii bilaterally but spared the rostral ventrolateral medulla. Absence of a functioning baroreflex was evidenced by the lack of reflex tachycardia to the hypotensive effects of sodium nitroprusside, exaggerated pressor responses to handgrip and cold pressor test, and exaggerated depressor responses to meals and centrally acting alpha 2-agonists. This clinicopathological correlate suggests that the patient's baroreflex failure can be explained by the unique combination of the destruction of sympathetic inhibitory centers (ie, the nucleus tractus solitarii) and preservation of centers that exert a positive modulation on sympathetic tone (ie, the rostral ventrolateral medulla).

  7. Characterization of neurons of the nucleus tractus solitarius pars centralis.

    PubMed

    Baptista, V; Zheng, Z L; Coleman, F H; Rogers, R C; Travagli, R A

    2005-08-09

    Esophageal sensory afferent inputs terminate principally in the central subnucleus of the tractus solitarius (cNTS). Neurons of the cNTS comprise two major neurochemical subpopulations. One contains neurons that are nitric oxide synthase (NOS) immunoreactive (-IR) while the other comprises neurons that are tyrosine hydroxylase (TH)-IR. We have shown recently that TH-IR neurons are involved in esophageal-distention induced gastric relaxation. We used whole cell patch clamp techniques in rat brainstem slices combined with immunohistochemical and morphological reconstructions to characterize cNTS neurons. Postrecording reconstruction of cNTS neurons revealed two morphological neuronal subtypes; one group of cells (41 out of 131 neurons, i.e., 31%) had a multipolar soma, while the other group (87 out of 131 neurons, i.e., 66%) had a bipolar soma. Of the 43 cells in which we conducted a neurochemical examination, 15 displayed TH-IR (9 with bipolar morphology, 6 with multipolar morphology) while the remaining 28 neurons did not display TH-IR (18 with bipolar morphology, 10 with multipolar morphology). Even though the range of electrophysiological properties varied significantly, morphological or neurochemical distinctions did not reveal characteristics peculiar to the subgroups. Spontaneous excitatory postsynaptic currents (sEPSC) recorded in cNTS neurons had a frequency of 1.5 +/- 0.15 events s(-1) and an amplitude of 27 +/- 1.2 pA (Vh = -50 mV) and were abolished by pretreatment with 30 muM AP-5 and 10 muM CNQX, indicating the involvement of both NMDA and non-NMDA receptors. Some cNTS neurons also received a GABAergic input that was abolished by perfusion with 30-50 muM bicuculline. In conclusion, our data show that despite the heterogeneity of morphological and neurochemical membrane properties, the electrophysiological characteristics of cNTS neurons are not a distinguishing feature.

  8. Terreneuvian Orthothecid (Hyolitha) Digestive Tracts from Northern Montagne Noire, France; Taphonomic, Ontogenetic and Phylogenetic Implications

    PubMed Central

    Devaere, Léa; Clausen, Sébastien; Álvaro, J. Javier; Peel, John S.; Vachard, Daniel

    2014-01-01

    More than 285 specimens of Conotheca subcurvata with three-dimensionally preserved digestive tracts were recovered from the Terreneuvian (early Cambrian) Heraultia Limestone of the northern Montagne Noire, southern France. They represent one of the oldest occurrences of such preserved guts. The newly discovered operculum of some complete specimens provides additional data allowing emendation of the species diagnosis. Infestation of the U-shaped digestive tracts by smooth uniseriate, branching to anastomosing filaments along with isolated botryoidal coccoids attests to their early, microbially mediated phosphatisation. Apart from taphonomic deformation, C. subcurvata exhibits three different configurations of the digestive tract: (1) anal tube and gut parallel, straight to slightly undulating; (2) anal tube straight and loosely folded gut; and (3) anal tube straight and gut straight with local zigzag folds. The arrangement of the digestive tracts and its correlation with the mean apertural diameter of the specimens are interpreted as ontogenetically dependent. The simple U-shaped gut, usually considered as characteristic of the Hyolithida, developed in earlier stages of C. subcurvata, whereas the more complex orthothecid type-3 only appears in largest specimens. This growth pattern suggests a distinct phylogenetic relationship between these two hyolith orders through heterochronic processes. PMID:24533118

  9. Terreneuvian orthothecid (Hyolitha) digestive tracts from northern Montagne Noire, France; taphonomic, ontogenetic and phylogenetic implications.

    PubMed

    Devaere, Léa; Clausen, Sébastien; Alvaro, J Javier; Peel, John S; Vachard, Daniel

    2014-01-01

    More than 285 specimens of Conotheca subcurvata with three-dimensionally preserved digestive tracts were recovered from the Terreneuvian (early Cambrian) Heraultia Limestone of the northern Montagne Noire, southern France. They represent one of the oldest occurrences of such preserved guts. The newly discovered operculum of some complete specimens provides additional data allowing emendation of the species diagnosis. Infestation of the U-shaped digestive tracts by smooth uniseriate, branching to anastomosing filaments along with isolated botryoidal coccoids attests to their early, microbially mediated phosphatisation. Apart from taphonomic deformation, C. subcurvata exhibits three different configurations of the digestive tract: (1) anal tube and gut parallel, straight to slightly undulating; (2) anal tube straight and loosely folded gut; and (3) anal tube straight and gut straight with local zigzag folds. The arrangement of the digestive tracts and its correlation with the mean apertural diameter of the specimens are interpreted as ontogenetically dependent. The simple U-shaped gut, usually considered as characteristic of the Hyolithida, developed in earlier stages of C. subcurvata, whereas the more complex orthothecid type-3 only appears in largest specimens. This growth pattern suggests a distinct phylogenetic relationship between these two hyolith orders through heterochronic processes.

  10. Bias in determining aluminum concentrations: Comparison of digestion methods and implications on Al management.

    PubMed

    He, Y Thomas; Ziemkiewicz, Paul F

    2016-09-01

    Aluminum is an important aquatic contaminant due to its ubiquity, toxicity and low regulatory discharge limits. Aluminum is mobilized in mining related, acidic drainage and is commonly a regulated pollutant. However, while aquatic toxicity studies and toxicity criteria are based on dissolved aluminum(Ald), discharge levels are, for statutory reasons, based on total recoverable aluminum (Alt). The rationale for using total recoverable aluminum recognizes the potential for the release of exchangeable, toxic cations or dissolution of metastable metal flocs in the event the discharge enters an acidic receiving stream. The digestion methods used in determining total recoverable metals are not meant to dissolve aluminosilicate clay particles but we found that they do, resulting in positively biased total recoverable aluminum values. This study explored the interaction between total suspended solids (TSS) and total recoverable aluminum using three digestion methods to evaluate which method introduced the least bias. Using field collected water and sediment samples from two coal mine drainage sites in Central West Virginia, three total recoverable digestion methods (USEPA Method 200.7, M1; USGS In-Bottle method, M2; and a Modified In-Bottle method, M3) were used to determine total recoverable aluminum across a range of total suspended solids concentrations. Baseline simulation experiments were conducted at pH 2.5, 3.5, 4.5 and 5.5 at different total suspended solids concentrations. Results indicated that dissolved aluminum did not respond to increasing total suspended solids concentrations while determined total recoverable aluminum increased with total suspended solids, indicating varying degrees of clay dissolution and, thus bias in the total recoverable aluminum concentration. While all three digestion methods overestimated total recoverable aluminum, at the same total suspended solids concentration, total recoverable aluminum extracted by USEPA Method 200.7 (M1) was

  11. Dairy manure resource recovery utilizing two-stage anaerobic digestion - Implications of solids fractionation.

    PubMed

    Stowe, Edmond J; Coats, Erik R; Brinkman, Cynthia K

    2015-12-01

    Dairy manure management is increasingly becoming an environmental challenge. In this regard, manure anaerobic digestion (AD) can be applied to address environmental concerns; however, dairy manure AD remains economically uncompetitive. Ongoing research is focused on enhanced resource recovery from manure, including maximizing AD methane yield through a novel multi-stage AD configuration. Research presented herein centered on the hypothesis that separately digesting fine and coarse solids from fermented dairy manure would improve methane production; the hypothesis was disproven. While maximum methane concentration was realized on fine solids, combined solids AD yielded enhanced VS destruction. The diverse combined-solids substrate enriched for a more heterogeneous bacterial/archaeal consortium that balanced fermentation and methanogenesis to yield maximum product (methane). However, results suggest that targeted AD of the fat-rich fine solids could be a more optimal approach for processing manure; alternate (non-AD) methods could then be applied to extract value from the fibrous fraction.

  12. Implications from distinct sulfate-reducing bacteria populations between cattle manure and digestate in the elucidation of H2S production during anaerobic digestion of animal slurry.

    PubMed

    St-Pierre, Benoit; Wright, André-Denis G

    2017-04-07

    Biogas produced from the anaerobic digestion of animal slurry consists mainly of methane (CH4) and carbon dioxide (CO2), but also includes other minor gases, such as hydrogen sulfide (H2S). Since it can act as a potent corrosive agent and presents a health hazard even at low concentrations, H2S is considered an undesirable by-product of anaerobic digestion. Sulfate-reducing bacteria (SRBs) have been identified as the main biological source of H2S in a number of natural, biological, and human-made habitats, and thus represent likely candidate microorganisms responsible for the production of H2S in anaerobic manure digesters. Phylogenetically, SRBs form a divergent group of bacteria that share a common anaerobic respiration pathway that allows them to use sulfate as a terminal electron acceptor. While the composition and activity of SRBs have been well documented in other environments, their metabolic potential remains largely uncharacterized and their populations poorly defined in anaerobic manure digesters. In this context, a combination of in vitro culture-based studies and DNA-based approaches, respectively, were used to gain further insight. Unexpectedly, only low to nondetectable levels of H2S were produced by digestate collected from a manure biogas plant documented to have persistently high concentrations of H2S in its biogas (2000-3000 ppm). In contrast, combining digestate with untreated manure (a substrate with comparatively lower sulfate and SRB cell densities than digestate) was found to produce elevated H2S levels in culture. While a 16S rRNA gene-based community composition approach did not reveal likely candidate SRBs in digestate or untreated manure, the use of the dsrAB gene as a phylogenetic marker provided more insight. In digestate, the predominant SRBs were found to be uncharacterized species likely belonging to the genus Desulfosporosinus (Peptococcaceae, Clostridiales, Firmicutes), while Desulfovibrio-related SRBs (Desulfovibrionaceae

  13. Anaplastic Lymphoma Kinase Rearrangement in Digestive Tract Cancer: Implication for Targeted Therapy in Chinese Population

    PubMed Central

    Wu, Jian; Guo, Lei; Qiu, Tian; Ling, Yun; Shan, Ling; Zhou, Haitao; Zhao, Dongbing; Wang, Jian; Liang, Jianwei; Zhao, Jianjun; Jiao, Yuchen; Lu, Ning; Zhao, Hong

    2015-01-01

    Background Anaplastic lymphoma kinase (ALK) rearrangements define a subgroup of lung cancer which is eligible to targeted kinase inhibition. The aim of this study is to observe the incidence rate of ALK fusion in a large cohort of Chinese digestive tract cancer patients. Patients and Methods Tissue microarray (TMA) was constructed from 808 digestive tract cancer cases, including 169 esophageal squamous cell carcinoma, 182 gastric cancer and 457 colorectal cancer (CRC) cases. We tested all cases for ALK expression via a fully automated immunohistochemistry (IHC) assay. The IHC-positive cases were subjected to fluorescence in situ hybridization (FISH), real-time polymerase chain reaction (qRT-PCR), target gene enrichment and sequencing for confirmation of ALK gene rearrangement and discovery of novel fusion partner. Results Among the tested cases, 2 (0.44%) CRC cases showed positive both by IHC and FISH. By qRT-PCR, EML4–ALK fusion was found in one IHC-positive CRC case. In another IHC-positive CRC case, target gene enrichment and sequencing revealed ALK was fused to a novel partner, spectrin beta non-erythrocytic 1 (SPTBN1). One gastric cancer case showed partially positive IHC result, but no fusion was found by FISH and gene sequencing. Conclusions The incidence rate of ALK gene fusion in Chinese CRC patients was 0.44%,but not detectable in gastric and esophageal cancers. The novel SPTBN1 -ALK fusion, together with other ALK fusion genes, may become a potential target for anti-ALK therapy. PMID:26678488

  14. Anaerobic digestion of agricultural and other substrates--implications for greenhouse gas emissions.

    PubMed

    Pucker, J; Jungmeier, G; Siegl, S; Pötsch, E M

    2013-06-01

    The greenhouse gas (GHG) emissions, expressed in carbon dioxide equivalents (CO2-eq), of different Austrian biogas systems were analyzed and evaluated using life-cycle assessment (LCA) as part of a national project. Six commercial biogas plants were investigated and the analysis included the complete process chain: viz., the production and collection of substrates, the fermentation of the substrates in the biogas plant, the upgrading of biogas to biomethane (if applicable) and the use of the biogas or biomethane for heat and electricity or as transportation fuel. Furthermore, the LCA included the GHG emissions of construction, operation and dismantling of the major components involved in the process chain, as well as the use of by-products (e.g. fermentation residues used as fertilizers). All of the biogas systems reduced GHG emissions (in CO2-eq) compared with fossil reference systems. The potential for GHG reduction of the individual biogas systems varied between 60% and 100%. Type of feedstock and its reference use, agricultural practices, coverage of storage tanks for fermentation residues, methane leakage at the combined heat and power plant unit and the proportion of energy used as heat were identified as key factors influencing the GHG emissions of anaerobic digestion processes.

  15. American alligator digestion rate of blue crabs and its implications for stomach contents analysis

    USGS Publications Warehouse

    Nifong, James C.; Rosenblatt, Adam E.; Johnson, Nathan A.; Barichivich, William; Silliman, Brian; Heithaus, Michael R.

    2012-01-01

    Stomach contents analysis (SCA) provides a snap-shot observation of a consumer's diet. Interpretation of SCA data can be complicated by many factors, including variation in gastric residence times and digestion rates among prey taxa. Although some SCA methods are reported to efficiently remove all stomach contents, the effectiveness of these techniques has rarely been tested for large irregular shaped prey with hard exoskeletons. We used a controlled feeding trial to estimate gastric residency time and decomposition rate of a large crustacean prey item, the Blue Crab (Callinectes sapidus), which is consumed by American Alligators (Alligator mississippiensis), an abundant apex predator in coastal habitats of the southeastern United States. The decomposition rate of C. sapidus in the stomachs of A. mississippiensis followed a predictable pattern, and some crab pieces remained in stomachs for at least 14 days. We also found that certain portions of C. sapidus were prone to becoming caught within the stomach or esophagus, meaning not all crab parts are consistently recovered using gastric lavage techniques. However, because the state of decomposition of crabs was predictable, it is possible to estimate time since consumption for crabs recovered from wild alligators. This information, coupled with a detailed understanding of crab distributions and alligator movement tactics could help elucidate patterns of cross-ecosystem foraging by the American Alligator in coastal habitats

  16. Members of the uncultured bacterial candidate division WWE1 are implicated in anaerobic digestion of cellulose

    PubMed Central

    Limam, Rim Driss; Chouari, Rakia; Mazéas, Laurent; Wu, Ting-Di; Li, Tianlun; Grossin-Debattista, Julien; Guerquin-Kern, Jean-Luc; Saidi, Mouldi; Landoulsi, Ahmed; Sghir, Abdelghani; Bouchez, Théodore

    2014-01-01

    Clones of the WWE1 (Waste Water of Evry 1) candidate division were retrieved during the exploration of the bacterial diversity of an anaerobic mesophilic (35 ± 0.5°C) digester. In order to investigate the metabolic function of WWE1 members, a 16S rRNA gene-based stable isotope probing (SIP) method was used. Eighty-seven percent of 16S r rRNA gene sequences affiliated to WWE1 candidate division were retrieved in a clone library obtained after polymerase chain reaction (PCR) amplification of enriched DNA fraction from anaerobic municipal solid waste samples incubated with 13C-cellulose, at the end of the incubation (day 63) using a Pla46F-1390R primer pair. The design of a specific WWE1 probe associated with the fluorescence in situ hybridization (FISH) technique corroborated the abundant representation of WWE1 members in our 13C-cellulose incubations. Secondary ion mass spectrometry–in situ hybridization (SIMSISH) using an iodine-labeled oligonucleotide probe combined with high-resolution nanometer-scale SIMS (NanoSIMS) observation confirmed the isotopic enrichment of members of WWE1 candidate division. The 13C apparent isotopic composition of hybridized WWE1 cells reached the value of about 40% early during the cellulose degradation process, suggesting that these bacteria play a role either in an extracellular cellulose hydrolysis process and/or in the uptake fermentation products. PMID:24497501

  17. Activation of 5-hyrdoxytryptamine 7 receptors within the rat nucleus tractus solitarii modulates synaptic properties

    PubMed Central

    Matott, Michael P.; Kline, David D.

    2016-01-01

    Serotonin (5-HT) is a potent neuromodulator with multiple receptor types within the cardiorespiratory system, including the nucleus tractus solitarii (nTS) - the central termination site of visceral afferent fibers. The 5-HT7 receptor facilitates cardiorespiratory reflexes through its action in the brainstem and likely in the nTS. However, the mechanism and site of action for these effects is not clear. In this study, we examined the expression and function of 5-HT7 receptors in the nTS of Sprague-Dawley rats. 5-HT7 receptor mRNA and protein were identified across the rostrocaudal extent of the nTS. To determine 5-HT7 receptor function, we examined nTS synaptic properties following 5-HT7 receptor activation in monosynaptic nTS neurons in the in vitro brainstem slice preparation. Application of 5-HT7 receptor agonists altered tractus solitarii evoked and spontaneous excitatory postsynaptic currents which were attenuated with a selective 5-HT7 receptor antagonist. 5-HT7 receptor-mediated changes in excitatory postsynaptic currents were also altered by block of 5-HT1A and GABAA receptors. Interestingly, 5-HT7 receptor activation also reduced the amplitude but not frequency of GABAA-mediated inhibitory currents. Together these results indicate a complex role for 5-HT7 receptors in the nTS that mediate its diverse effects on cardiorespiratory parameters. PMID:26779891

  18. Hypoxia-induced cellular and vascular changes in the nucleus tractus solitarius and ventrolateral medulla.

    PubMed

    Kaur, Charanjit; Viswanathan, Sivakumar; Ling, Eng-Ang

    2011-03-01

    Major changes in arterial pressure, autonomic, and respiratory activity occur in response to hypoxia. We analyzed structural damage and increased vascular permeability in the ventrolateral medulla and nucleus tractus solitarius, which control autonomic, respiratory, and cardiovascular functions in adult Wistar rats subjected to 2 hours of hypoxia (7% oxygen + 93% nitrogen) for up to 14 days after hypoxicexposure. Brainstem tissue levels of vascular endothelial growth factor (VEGF), nitric oxide (NO), and glutamate were significantly increased over control levels after hypoxic injury. By electron microscopy, swollen neurons and dendrites, degenerating axons, disrupted myelin sheaths, and swollen astrocyte processes were observed in the nucleus tractus solitarius and ventrolateral medulla. Leakage of intravenously administered horseradish peroxidase was observed through vascular walls in hypoxic rats. These results suggest that increased VEGF and NO production in hypoxia resulted in increased vascular permeability, which, along with increased levels of glutamate, may have induced structural alterations of the neurons, dendrites, and axons. Administration of the antioxidant neurohormone melatonin (10mg/kg) before and after the hypoxia reduced VEGF, NO, and glutamate levels and improved ultrastructural abnormalities induced by hypoxia exposure, suggesting that it may have a therapeutic potential in reducing hypoxia-associated brainstem damage.

  19. Metacomprehension. ERIC Digest.

    ERIC Educational Resources Information Center

    Standiford, Sally N.

    Intended for administrators and policymakers as well as teachers, this digest explores the nature of students' metacomprehension, or their awareness of their own understanding, and the implications of this awareness for reading instruction. After defining metacomprehension, the digest discusses why this awareness is important to the learning…

  20. Digestive Diseases

    MedlinePlus

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

  1. Digestive System

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old Digestive System KidsHealth > For Parents > Digestive System A A A ... the body can absorb and use. About the Digestive System Almost all animals have a tube-type digestive ...

  2. Implications of full-scale implementation of an anammox-based process as post-treatment of a municipal anaerobic sludge digester operated with co-digestion.

    PubMed

    Vázquez-Padín, J R; Morales, N; Gutiérrez, R; Fernández, R; Rogalla, F; Barrio, J P; Campos, J L; Mosquera-Corral, A; Méndez, R

    2014-01-01

    The feasibility of treating the supernatant of a municipal sludge digester supplemented with co-substrates by means of an anammox-based process (ELAN(®)) was tested in Guillarei (NW of Spain). Ammonia concentration measured in the supernatant of the sludge digester varied in the range 800-1,500 g N/m(3) due to the fact that the sludge produced in the plant was co-digested with wastes coming from surrounding food industries. Treating this supernatant in the ELAN(®) reactor, nitrogen removal rates up to 1.1 kg N/(m(3) d) were reached in experiments run in a pilot plant reactor operated in batch mode. No nitrite oxidation was registered after several months of operation despite the average dissolved oxygen (DO) concentrations being 1.5 g O2/m(3) and the temperature reaching values as low as 18 °C. By keeping the DO set point at 1-2 g O2/m(3) and tuning the hydraulic retention time, the stability of the process was guaranteed and the presence of co-substrates in the anaerobic digester did not affect negatively the operation of the autotrophic nitrogen removal process. Due to the success of the pilot plant experiment, an upscale of the process to full scale is proposed. Mass balances applied to Guillarei wastewater treatment plant revealed that in the main stream line the average denitrification rate calculated with the data of year 2011 was 226 kg N/d. Since the nitrogen removal efficiency is limited by the amount of readily biodegradable organic matter available to carry out denitrification in the water line, the implementation of an anammox-based process to treat the supernatant seems the best option to improve the effluent quality in terms of nitrogen content. The nitrogen removal rate in the sludge line would be 30 times higher than the one in the water line. The implementation of the process would improve the energetic balance and the nitrogen removal performance of the plant.

  3. Estrogen-dependent enhancement of NO production in the nucleus tractus solitarius contributes to ethanol-induced hypotension in conscious female rats

    PubMed Central

    Li, Guichu; Abdel-Rahman, Abdel A.

    2009-01-01

    Background Our previous pharmacological and cellular studies showed that peripheral (cardiac and vascular) NOS-derived NO is implicated in the estrogen-dependent hypotensive action of ethanol in female rats. The objective of this study was to test the hypothesis that enhanced NO production in the nucleus tractus solitarius (NTS) is implicated in the estrogen-dependent hypotensive action of ethanol. Methods To achieve this goal, we utilized in vivo electrochemistry to measure real time changes in neuronal NO to investigate the acute effects of intragastric ethanol (0, 0.5 or 1 g/kg) on NO in NTS neurons, blood pressure (BP) and heart rate (HR) in conscious female rats in the absence (ovariectomized, OVX, rats) or presence of estrogen. Results In sham operated (SO) rats, ethanol elicited dose-related increase in NTS NO and reduction in BP. These neurochemical and blood pressure effects of ethanol were absent in OVX rats. Whether the neurochemical effect of ethanol and the associated hypotension are dependent on rapid estrogen signaling was investigated. In OVX rats pretreated, 30 min earlier, with estrogen (E2, 1µg/kg), intragastric ethanol (1 g/kg) increased NTS NO and reduced BP and these responses were comparable to those obtained in SO rats. Conclusions The present findings suggest that increased production of NO in NTS neurons contributes to ethanol-evoked hypotension in female rats. Further, ethanol enhancement of neuronal NO production in the brainstem is dependent on rapid estrogen signaling. PMID:19076118

  4. Key role of 5-HT3 receptors in the nucleus tractus solitarii in cardiovagal stress reactivity.

    PubMed

    Sévoz-Couche, Caroline; Brouillard, Charly

    2017-03-01

    Serotonin plays a modulatory role in central control of the autonomic nervous system (ANS). The nucleus tractus solitarii (NTS) in the medulla is an area of viscerosomatic integration innervated by both central and peripheral serotonergic fibers. Influences from different origins therefore trigger the release of serotonin into the NTS and exert multiple influences on the ANS. This major influence on the ANS is also mediated by activation of several receptors in the NTS. In particular, the NTS is the central zone with the highest density of serotonin3 (5-HT3) receptors. In this review, we present evidence that 5-HT3 receptors in the NTS play a key role in one of the crucial homeostatic responses to acute and chronic stress: inhibitory modulation of the parasympathetic component of the ANS. The possible functional interactions of 5-HT3 receptors with GABAA and NK1 receptors in the NTS are also discussed.

  5. The nucleus of the tractus solitarius of the dog. A morphological and morphometric analysis.

    PubMed Central

    Ruiz Pesini, P; Cifuentes, J M; Fernandez-Troconiz, P

    1991-01-01

    The neuronal and fibrous architecture of the nucleus of the tractus solitarius (NTS) of the dog has been studied in transversely cut Nissl, myelin and reduced silver stained serial sections. Eight distinct subdivisions, clearly delimited both by their cytoarchitectonic and fibrous characteristics, have been identified. They are: the commissural, gelatinous, lateral, interstitial, dorsolateral, ventrolateral, intermediate and medial subdivisions. Their rostrocaudal extensions and locations in relation to the obex are summarised in Table 1. A morphometric analysis was additionally done. The frequency distributions of cell areas and cell form factor of each subdivision are represented by histograms in Figures 8 and 9 respectively. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 PMID:1717419

  6. Re-evaluation of the mechanisms of dietary fibre and implications for macronutrient bioaccessibility, digestion and postprandial metabolism.

    PubMed

    Grundy, Myriam M-L; Edwards, Cathrina H; Mackie, Alan R; Gidley, Michael J; Butterworth, Peter J; Ellis, Peter R

    2016-09-01

    The positive effects of dietary fibre on health are now widely recognised; however, our understanding of the mechanisms involved in producing such benefits remains unclear. There are even uncertainties about how dietary fibre in plant foods should be defined and analysed. This review attempts to clarify the confusion regarding the mechanisms of action of dietary fibre and deals with current knowledge on the wide variety of dietary fibre materials, comprising mainly of NSP that are not digested by enzymes of the gastrointestinal (GI) tract. These non-digestible materials range from intact cell walls of plant tissues to individual polysaccharide solutions often used in mechanistic studies. We discuss how the structure and properties of fibre are affected during food processing and how this can impact on nutrient digestibility. Dietary fibre can have multiple effects on GI function, including GI transit time and increased digesta viscosity, thereby affecting flow and mixing behaviour. Moreover, cell wall encapsulation influences macronutrient digestibility through limited access to digestive enzymes and/or substrate and product release. Moreover, encapsulation of starch can limit the extent of gelatinisation during hydrothermal processing of plant foods. Emphasis is placed on the effects of diverse forms of fibre on rates and extents of starch and lipid digestion, and how it is important that a better understanding of such interactions with respect to the physiology and biochemistry of digestion is needed. In conclusion, we point to areas of further investigation that are expected to contribute to realisation of the full potential of dietary fibre on health and well-being of humans.

  7. Hypoglycemia-activated GLUT2 neurons of the nucleus tractus solitarius stimulate vagal activity and glucagon secretion.

    PubMed

    Lamy, Christophe M; Sanno, Hitomi; Labouèbe, Gwenaël; Picard, Alexandre; Magnan, Christophe; Chatton, Jean-Yves; Thorens, Bernard

    2014-03-04

    Glucose-sensing neurons in the brainstem participate in the regulation of energy homeostasis but have been poorly characterized because of the lack of specific markers to identify them. Here we show that GLUT2-expressing neurons of the nucleus of the tractus solitarius form a distinct population of hypoglycemia-activated neurons. Their response to low glucose is mediated by reduced intracellular glucose metabolism, increased AMP-activated protein kinase activity, and closure of leak K(+) channels. These are GABAergic neurons that send projections to the vagal motor nucleus. Light-induced stimulation of channelrhodospin-expressing GLUT2 neurons in vivo led to increased parasympathetic nerve firing and glucagon secretion. Thus GLUT2 neurons of the nucleus tractus solitarius link hypoglycemia detection to counterregulatory response. These results may help identify the cause of hypoglycemia-associated autonomic failure, a major threat in the insulin treatment of diabetes.

  8. Extended secondhand tobacco smoke exposure induces plasticity in nucleus tractus solitarius second-order lung afferent neurons in young guinea pigs.

    PubMed

    Sekizawa, Shin-Ichi; Chen, Chao-Yin; Bechtold, Andrea G; Tabor, Jocelyn M; Bric, John M; Pinkerton, Kent E; Joad, Jesse P; Bonham, Ann C

    2008-08-01

    Infants and young children experiencing extended exposure to secondhand smoke (SHS) have an increased occurrence of asthma, as well as increased cough, wheeze, mucus production and airway hyper-reactivity. Plasticity in lung reflex pathways has been implicated in causing these symptoms, as have changes in substance P-related mechanisms. Using whole-cell voltage-clamp recordings and immunohistochemistry in brainstem slices containing anatomically identified second-order lung afferent nucleus tractus solitarius (NTS) neurons, we determined whether extended SHS exposure during the equivalent period of human childhood modified evoked or spontaneous excitatory synaptic transmission, and whether those modifications were altered by endogenous substance P. SHS exposure enhanced evoked synaptic transmission between sensory afferents and the NTS second-order neurons by eliminating synaptic depression of evoked excitatory postsynaptic currents (eEPSCs), an effect reversed by the neurokinin-1-receptor antagonist (SR140333). The recruitment of substance P in enhancing evoked synaptic transmission was further supported by an increased number of substance P-expressing lung afferent central terminals synapsing onto the second-order lung afferent neurons. SHS exposure did not change background spontaneous EPSCs. The data suggest that substance P in the NTS augments evoked synaptic transmission of lung sensory input following extended exposure to a pollutant. The mechanism may help to explain some of the exaggerated respiratory responses of children exposed to SHS.

  9. Changes in Digestive Rate of a Predatory Beetle over Its Larval Stage: Its Implications for Dietary Breadth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prey and non-prey foods differ substantially in their suitability for zoophytophagous omnivores, but the relative quality of these foods depends on the stage-specific digestive capabilities of the organism in question. Quantitative (or real-time) PCR involving food-specific primer sets was used to m...

  10. Binturong (Arctictis binturong) and Kinkajou (Potos flavus) Digestive Strategy: Implications for Interpreting Frugivory in Carnivora and Primates

    PubMed Central

    Lambert, Joanna E.; Fellner, Vivek; McKenney, Erin; Hartstone-Rose, Adam

    2014-01-01

    Exclusive frugivory is rare. As a food resource, fruit is temporally and spatially patchy, low in protein, and variable in terms of energy yield from different carbohydrate types. Here, we evaluate the digestive physiology of two frugivorous Carnivora species (Potos flavus, Arctictis binturong) that converge with primates in a diversity of ecological and anatomical traits related to fruit consumption. We conducted feeding trials to determine mean digestive retention times (MRT) on captive animals at the Carnivore Preservation Trust (now Carolina Tiger Rescue), Pittsboro, NC. Fecal samples were collected on study subjects for in vitro analysis to determine methane, pH, and short chain fatty acid profiles; fiber was assayed using standard neutral detergent (NDF) and acid detergent (ADF) fiber methods. Results indicate that both carnivoran species have rapid digestive passage for mammals that consume a predominantly plant-based diet: A. binturong MRT = 6.5 hrs (0.3); P. flavus MRT = 2.5 hrs (1.6). In vitro experiments revealed no fermentation of structural polysaccharides – methane levels did not shift from 0 h to either 24 or 48 hours and no short chain fatty acids were detected. In both species, however, pH declined from one incubation period to another suggesting acidification and bacterial activity of microbes using soluble carbohydrates. A comparison with primates indicates that the study species are most similar in digestive retention times to Ateles – the most frugivorous anthropoid primate taxon. PMID:25157614

  11. Environmental implications of anaerobic digestion for manure management in dairy farms in Mexico: a life cycle perspective.

    PubMed

    Rivas-García, Pasiano; Botello-Álvarez, José E; Abel Seabra, Joaquim E; da Silva Walter, Arnaldo C; Estrada-Baltazar, Alejandro

    2015-01-01

    The environmental profile of milk production in Mexico was analysed for three manure management scenarios: fertilization (F), anaerobic digestion (AD) and enhanced anaerobic digestion (EAD). The study used the life cycle assessment (LCA) technique, considering a 'cradle-to-gate' approach. The assessment model was constructed using SimaPro LCA software, and the life cycle impact assessment was performed according to the ReCiPe method. Dairy farms with AD and EAD scenarios were found to exhibit, respectively, 12% and 27% less greenhouse gas emissions, 58% and 31% less terrestrial acidification, and 3% and 18% less freshwater eutrophication than the F scenario. A different trend was observed in the damage to resource availability indicator, as the F scenario presented 6% and 22% less damage than the EAD and AD scenarios, respectively. The magnitude of environmental damage from milk production in the three dairy manure management scenarios, using a general single score indicator, was 0.118, 0.107 and 0.081 Pt/L of milk for the F, AD and EAD scenarios, respectively. These results indicate that manure management systems with anaerobic digestion can improve the environmental profile of each litre of milk produced.

  12. Kinetic Stability of Proteins in Beans and Peas: Implications for Protein Digestibility, Seed Germination, and Plant Adaptation.

    PubMed

    Xia, Ke; Pittelli, Sandy; Church, Jennifer; Colón, Wilfredo

    2016-10-12

    Kinetically stable proteins (KSPs) are resistant to the denaturing detergent sodium dodecyl sulfate (SDS). Such resilience makes KSPs resistant to proteolytic degradation and may have arisen in nature as a mechanism for organismal adaptation and survival against harsh conditions. Legumes are well-known for possessing degradation-resistant proteins that often diminish their nutritional value. Here we applied diagonal two-dimensional (D2D) SDS-polyacrylamide gel electrophoresis (PAGE), a method that allows for the proteomics-level identification of KSPs, to a group of 12 legumes (mostly beans and peas) of agricultural and nutritional importance. Our proteomics results show beans that are more difficult to digest, such as soybean, lima beans, and various common beans, have high contents of KSPs. In contrast, mung bean, red lentil, and various peas that are highly digestible contain low amounts of KSPs. Identified proteins with high kinetic stability are associated with warm-season beans, which germinate at higher temperatures. In contrast, peas and red lentil, which are cool-season legumes, contain low levels of KSPs. Thus, our results show protein kinetic stability is an important factor in the digestibility of legume proteins and may relate to nutrition efficiency, timing of seed germination, and legume resistance to biotic stressors. Furthermore, we show D2D SDS-PAGE is a powerful method that could be applied for determining the abundance and identity of KSPs in engineered and wild legumes and for advancing basic research and associated applications.

  13. Propofol facilitated excitatory postsynaptic currents frequency on nucleus tractus solitarii (NTS) neurons.

    PubMed

    Jin, Zhenhua; Choi, Myung-Jin; Park, Cheung-Seog; Park, Young Seek; Jin, Young-Ho

    2012-01-13

    Propofol, an intravenous anesthetic, is broadly used for general anesthesia and diagnostic sedations due to its fast onset and recovery. Propofol depresses respiratory and cardiovascular reflex responses, however, their underlying mechanisms are not well known. Cardiorespiratory information from visceral afferent vagus nerves is integrated in the nucleus tractus solitarii (NTS). Cardiac and respiratory signals transducing vagal afferent neurons release the excitatory neurotransmitter glutamate onto NTS neurons in an activity dependent manner and trigger negative feedback reflex responses. In this experiment, the effects of propofol on glutamatergic synaptic responses at NTS neurons was tested using patch clamp methods. Glutamatergic excitatory postsynaptic currents (EPSC) were recorded at chloride reversal potential (-49mV) without γ-aminobutyric acid type A (GABA(A)) receptor antagonists. Propofol (≥3μM) facilitated frequency of the spontaneous EPSCs in a concentration dependent manner without altering amplitude and decay time. The GABA(A) receptor selective antagonist, gabazine (6μM), attenuated propofol effects on glutamate release. Propofol (10μM) evoked glutamate release was also blocked in the presence of the voltage dependent Na(+) and Ca(2+) channel blockers TTX (0.3μM) and Cd(2+) (0.2mM), respectively. In addition, the Na(+)-K(+)-Cl(-) cotransporter type 1 antagonist bumetanide (10μM) also inhibited propofol evoked increase in sEPSC frequency. These results suggest that propofol evoked glutamate release onto NTS neurons by GABA(A) receptor-mediated depolarization of the presynaptic excitatory terminals.

  14. Chronic intermittent hypoxia affects integration of sensory input by neurons in the nucleus tractus solitarii.

    PubMed

    Kline, David D

    2010-11-30

    The autonomic nervous and respiratory systems, as well as their coupling, adapt over a wide range of conditions. Chronic intermittent hypoxia (CIH) is a model for recurrent apneas and induces alterations in breathing and increases in sympathetic nerve activity which may ultimately result in hypertension if left untreated. These alterations are believed to be due to increases in the carotid body chemoreflex pathway. Here we present evidence that the nucleus tractus solitarii (nTS), the central brainstem termination site of chemoreceptor afferents, expresses a form of synaptic plasticity that increases overall nTS activity following intermittent hypoxia. Following CIH, an increase in presynaptic spontaneous neurotransmitter release occurs under baseline conditions. Furthermore, during and following afferent stimulation there is an augmentation of spontaneous transmitter release that occurs out of synchrony with sensory stimulation. On the other hand, afferent evoked synchronous transmitter release is attenuated. Overall, this shift from synchronous to asynchronous transmitter release enhances nTS cellular discharge. The role of the neurotransmitter dopamine in CIH-induced plasticity is also discussed. Dopamine attenuates synaptic transmission in nTS cells by blockade of N-type calcium channels, and this mechanism occurs tonically following normoxia and CIH. This dopaminergic pathway, however, is not altered in CIH. Taken together, alterations in nTS synaptic activity may play a role in the changes of chemoreflex function and cardiorespiratory activity in the CIH apnea model.

  15. Aldosterone induces rapid sodium intake by a nongenomic mechanism in the nucleus tractus solitarius

    PubMed Central

    Qiao, Hu; Hu, Bo; Zhou, Hong; Yan, Jianqun; Jia, Ru; Lu, Bo; Sun, Bo; Luo, Xiao; Fan, Yuanyuan; Wang, Nan

    2016-01-01

    The purpose of this study was to determine whether aldosterone has a rapid action in the nucleus tractus solitarius (NTS) that increases sodium intake, and to examine whether this effect of aldosterone, if present, is mediated by G protein-coupled estrogen receptor (GPER). Adult male Sprague-Dawley rats with a stainless-steel cannula in the NTS were used. Aldosterone was injected into the NTS at the doses of 1, 5, 10 and 20 ng 0.1 μl−1. A rapid dose-related increase of 0.3 M NaCl intake was induced within 30 min and this increase was not suppressed by the mineralocorticoid receptor (MR) antagonist spironolactone (10 ng 0.1 μl−1). Water intake was not affected by aldosterone. The GPER agonist G-1 produced a parallel and significant increase in sodium intake, while pre-treatment with GPER antagonist G15 (10 ng 0.1 μl−1) blocked the G-1 or aldosterone-induced rapid sodium intake. In addition, sodium intake induced by sodium depletion or low-sodium diet fell within 30 min after injection into the NTS of the MR antagonist spironolactone, while G15 had no effect. Our results confirm previous reports, and support the hypothesis that aldosterone evokes rapid sodium intake through a non-genomic mechanism involving GPER in NTS. PMID:27934887

  16. Sudden Death Following Selective Neuronal Lesions in the Rat Nucleus Tractus Solitarii

    PubMed Central

    Talman, William T.; Lin, Li-Hsien

    2013-01-01

    In efforts to assess baroreflex and cardiovascular responses in rats in which substance P (SP) or catecholamine transmission had been eliminated we studied animals after bilateral injections into the nucleus tractus solitarii (NTS) of SP or stabilized SP (SSP) conjugated to saporin (SP-SAP or SSP-SAP respectively) or SAP conjugated to an antibody to dopamine-β-hydroxylase (anti-DBH-SAP). We found that SP- and SSP-SAP eliminated NTS neurons that expressed the SP neurokinin-1 receptor (NK1R) while anti-DBH-SAP eliminated NTS neurons expressing tyrosine hydroxylase (TH) and DBH. The toxins were selective. Thus SP-or SSP-SAP did not eliminate TH/DBH neurons and anti-DBH-SAP did not eliminate NK1R neurons in the NTS. Each toxin, however, led to chronic lability of arterial blood pressure, diminished baroreflex function, cardiac ventricular irritability, coagulation necrosis of cardiac myocytes and, in some animals, sudden death associated with asystole. However, when TH/DBH neurons were targeted and eliminated by injection of 6-hydroxydopamine (6-OHDA), none of the cardiovascular or cardiac changes occurred. The studies reviewed here reveal that selective lesions of the NTS lead to altered baroreflex control and to cardiac changes that may lead to sudden death. Though the findings could support a role for SP or catecholamines in baroreflex transmission neither is proven in that NK1R colocalizes with glutamate receptors. Thus neurons with both are lost when treated with SP- or SSP-SAP. In addition, loss of catecholamine neurons after treatment with 6-OHDA does not affect cardiovascular control. Thus, the effect of the toxins may depend on an action of SAP independent of the effects of the SAP conjugates on targeted neuronal types. PMID:23245583

  17. Endogenous Opiates in the Nucleus Tractus Solitarius Mediate Electroacupuncture-Induced Sleep Activities in Rats

    PubMed Central

    Cheng, Chiung-Hsiang; Yi, Pei-Lu; Lin, Jaung-Geng; Chang, Fang-Chia

    2011-01-01

    Electroacupuncture (EA) possesses various therapeutic effects, including alleviation of pain, reduction of inflammation and improvement of sleep disturbance. The mechanisms of EA on sleep improvement, however, remain to be determined. It has been stated in ancient Chinese literature that the Anmian (EX17) acupoint is one of the trigger points that alleviates insomnia. We previously demonstrated that EA stimulation of Anmian acupoints in rats during the dark period enhances non-rapid eye movement (NREM) sleep, which involves the induction of cholinergic activity in the nucleus tractus solitarius (NTS). In addition to cholinergic activation of the NTS, activation of the endogenous opioidergic system may also be a mechanism by which acupuncture affects sleep. Therefore, this study was designed to investigate the involvement of the NTS opioidergic system in EA-induced alterations in sleep. Our present results indicate that EA of Anmian acupoints increased NREM sleep, but not rapid eye movement sleep, during the dark period in rats. This enhancement in NREM sleep was dose-dependently blocked by microinjection of opioid receptor antagonist, naloxone, and the μ-opioid receptor antagonist, naloxonazine, into the NTS; administrations of δ-receptor antagonist, natrindole, and the κ-receptor antagonist, nor-binaltrophimine, however, did not affect EA-induced alterations in sleep. Furthermore, β-endorphin was significantly increased in both the brainstem and hippocampus after the EA stimuli, an effect blocked by administration of the muscarinic antagonist scopolamine into the NTS. Our findings suggest that mechanisms of EA-induced NREM sleep enhancement may be mediated, in part, by cholinergic activation, stimulation of the opiodergic neurons to increase the concentrations of β-endorphin and the involvement of the μ-opioid receptors. PMID:19729491

  18. Glutamate receptors in the nucleus tractus solitarius contribute to ventilatory acclimatization to hypoxia in rat

    PubMed Central

    Pamenter, Matthew E; Carr, J Austin; Go, Ariel; Fu, Zhenxing; Reid, Stephen G; Powell, Frank L

    2014-01-01

    When exposed to a hypoxic environment the body's first response is a reflex increase in ventilation, termed the hypoxic ventilatory response (HVR). With chronic sustained hypoxia (CSH), such as during acclimatization to high altitude, an additional time-dependent increase in ventilation occurs, which increases the HVR. This secondary increase persists after exposure to CSH and involves plasticity within the circuits in the central nervous system that control breathing. Currently these mechanisms of HVR plasticity are unknown and we hypothesized that they involve glutamatergic synapses in the nucleus tractus solitarius (NTS), where afferent endings from arterial chemoreceptors terminate. To test this, we treated rats held in normoxia (CON) or 10% O2 (CSH) for 7 days and measured ventilation in conscious, unrestrained animals before and after microinjecting glutamate receptor agonists and antagonists into the NTS. In normoxia, AMPA increased ventilation 25% and 50% in CON and CSH, respectively, while NMDA doubled ventilation in both groups (P < 0.05). Specific AMPA and NMDA receptor antagonists (NBQX and MK801, respectively) abolished these effects. MK801 significantly decreased the HVR in CON rats, and completely blocked the acute HVR in CSH rats but had no effect on ventilation in normoxia. NBQX decreased ventilation whenever it was increased relative to normoxic controls; i.e. acute hypoxia in CON and CSH, and normoxia in CSH. These results support our hypothesis that glutamate receptors in the NTS contribute to plasticity in the HVR with CSH. The mechanism underlying this synaptic plasticity is probably glutamate receptor modification, as in CSH rats the expression of phosphorylated NR1 and GluR1 proteins in the NTS increased 35% and 70%, respectively, relative to that in CON rats. PMID:24492841

  19. Glutamate receptors in the nucleus tractus solitarius contribute to ventilatory acclimatization to hypoxia in rat.

    PubMed

    Pamenter, Matthew E; Carr, J Austin; Go, Ariel; Fu, Zhenxing; Reid, Stephen G; Powell, Frank L

    2014-04-15

    When exposed to a hypoxic environment the body's first response is a reflex increase in ventilation, termed the hypoxic ventilatory response (HVR). With chronic sustained hypoxia (CSH), such as during acclimatization to high altitude, an additional time-dependent increase in ventilation occurs, which increases the HVR. This secondary increase persists after exposure to CSH and involves plasticity within the circuits in the central nervous system that control breathing. Currently these mechanisms of HVR plasticity are unknown and we hypothesized that they involve glutamatergic synapses in the nucleus tractus solitarius (NTS), where afferent endings from arterial chemoreceptors terminate. To test this, we treated rats held in normoxia (CON) or 10% O2 (CSH) for 7 days and measured ventilation in conscious, unrestrained animals before and after microinjecting glutamate receptor agonists and antagonists into the NTS. In normoxia, AMPA increased ventilation 25% and 50% in CON and CSH, respectively, while NMDA doubled ventilation in both groups (P < 0.05). Specific AMPA and NMDA receptor antagonists (NBQX and MK801, respectively) abolished these effects. MK801 significantly decreased the HVR in CON rats, and completely blocked the acute HVR in CSH rats but had no effect on ventilation in normoxia. NBQX decreased ventilation whenever it was increased relative to normoxic controls; i.e. acute hypoxia in CON and CSH, and normoxia in CSH. These results support our hypothesis that glutamate receptors in the NTS contribute to plasticity in the HVR with CSH. The mechanism underlying this synaptic plasticity is probably glutamate receptor modification, as in CSH rats the expression of phosphorylated NR1 and GluR1 proteins in the NTS increased 35% and 70%, respectively, relative to that in CON rats.

  20. Endogenous opiates in the nucleus tractus solitarius mediate electroacupuncture-induced sleep activities in rats.

    PubMed

    Cheng, Chiung-Hsiang; Yi, Pei-Lu; Lin, Jaung-Geng; Chang, Fang-Chia

    2011-01-01

    Electroacupuncture (EA) possesses various therapeutic effects, including alleviation of pain, reduction of inflammation and improvement of sleep disturbance. The mechanisms of EA on sleep improvement, however, remain to be determined. It has been stated in ancient Chinese literature that the Anmian (EX17) acupoint is one of the trigger points that alleviates insomnia. We previously demonstrated that EA stimulation of Anmian acupoints in rats during the dark period enhances non-rapid eye movement (NREM) sleep, which involves the induction of cholinergic activity in the nucleus tractus solitarius (NTS). In addition to cholinergic activation of the NTS, activation of the endogenous opioidergic system may also be a mechanism by which acupuncture affects sleep. Therefore, this study was designed to investigate the involvement of the NTS opioidergic system in EA-induced alterations in sleep. Our present results indicate that EA of Anmian acupoints increased NREM sleep, but not rapid eye movement sleep, during the dark period in rats. This enhancement in NREM sleep was dose-dependently blocked by microinjection of opioid receptor antagonist, naloxone, and the μ-opioid receptor antagonist, naloxonazine, into the NTS; administrations of δ-receptor antagonist, natrindole, and the κ-receptor antagonist, nor-binaltrophimine, however, did not affect EA-induced alterations in sleep. Furthermore, β-endorphin was significantly increased in both the brainstem and hippocampus after the EA stimuli, an effect blocked by administration of the muscarinic antagonist scopolamine into the NTS. Our findings suggest that mechanisms of EA-induced NREM sleep enhancement may be mediated, in part, by cholinergic activation, stimulation of the opiodergic neurons to increase the concentrations of β-endorphin and the involvement of the μ-opioid receptors.

  1. Leptin signaling in the nucleus tractus solitarii increases sympathetic nerve activity to the kidney.

    PubMed

    Mark, Allyn L; Agassandian, Khristofor; Morgan, Donald A; Liu, Xuebo; Cassell, Martin D; Rahmouni, Kamal

    2009-02-01

    The hypothalamic arcuate nucleus was initially regarded as the principal site of leptin action, but there is increasing evidence for functional leptin receptors in extrahypothalamic sites, including the nucleus tractus solitarii (NTS). We demonstrated previously that arcuate injection of leptin increases sympathetic nerve activity (SNA) to brown adipose tissue and kidney. In this study, we tested the hypothesis that leptin signaling in the NTS affects sympathetic neural outflow. Using a stereotaxic device in anesthetized rats, we microinjected leptin (0.25 to 1.00 microg) or saline into the NTS while recording SNA to kidney and brown adipose tissue. Microinjection of leptin into the commissural and medial subnuclei of the caudal NTS at the level of the area postrema in Sprague-Dawley rats produced a dose-related increase in renal SNA (+112+/-15% with leptin 1 microg; n=7; P<0.001) but did not increase SNA to brown adipose tissue (-15+/-12%; P value not significant). This effect depended on intact functional leptin receptors, because it was not observed in Zucker obese rats that have a missense mutation in the leptin receptor. Rostral NTS injection of leptin failed to increase SNA, indicating that leptin signaling in the NTS is probably confined to the caudal NTS at the level of the area postrema. In summary, this study demonstrates that leptin signaling in the caudal NTS increases SNA to the kidney but not to the brown adipose tissue. The study strengthens the concept of a distributed brain network of leptin action and demonstrates that these distributed brain sites can mediate contrasting sympathetic responses to leptin.

  2. Carcinome papillaire sur kyste du tractus thyréoglosse: à propos de deux cas

    PubMed Central

    Dbab, Lamia; Nouri, Hassan; Iguelouane, Nassim; Rochdi, Youssef; Aderdour, Lahcen; Raji, Abdelaziz

    2015-01-01

    L'objectif de ce travail est de présenté deux cas de carcinomes papillaire sur kystes du tractus thyréoglosse (KTT) et d'exposer notre attitude thérapeutique. Il s'agit de deux patientes, une âgée de 30 ans et l'autre de 45 ans, qui ont été opéré dans notre centre. Le diagnostic du carcinome papillaire sur KTT a été retenu après étude anatomopathologique du kyste après exérèse selon la technique de Sistrunk. Une thyroïdectomie totale suivie d'une irathérapie et d'une hormonothérapie freinatrice a été réalisé chez l'une des patientes, pour l'autre une thyroïdectomie totale associée à une hormonothérapie freinatrice a été préconisé. L'évolution été favorable après un recule de 4 ans pour la première patiente et de 2 ans pour la deuxième. La thyroïdectomie totale après exérèse complète du KTT est le traitement recommandé pour le carcinome papillaire sur KTT. Il a été démontré qu'un cancer latent de la thyroïde peut être développé même après des années après l'exérèse du KTT. Le traitement du carcinome papillaire sur KTT est bien codifié, permettant un excellent pronostic. PMID:26848352

  3. Moderate Hyperbilirubinemia Alters Neonatal Cardiorespiratory Control and Induces Inflammation in the Nucleus Tractus Solitarius

    PubMed Central

    Specq, Marie-Laure; Bourgoin-Heck, Mélisande; Samson, Nathalie; Corbin, François; Gestreau, Christian; Richer, Maxime; Kadhim, Hazim; Praud, Jean-Paul

    2016-01-01

    Hyperbilirubinemia (HB) occurs in 90% of preterm newborns. Moderate HB can induce acute neurological disorders while severe HB has been linked to a higher incidence of apneas of prematurity. The present study aimed to test the hypothesis that even moderate HB disrupts cardiorespiratory control in preterm lambs. Two groups of preterm lambs (born 14 days prior to term), namely control (n = 6) and HB (n = 5), were studied. At day 5 of life, moderate HB (150–250 μmol/L) was induced during 17 h in the HB group after which cardiorespiratory control as well as laryngeal and pulmonary chemoreflexes were assessed during baseline recordings and during hypoxia. Recordings were repeated 72 h after HB induction, just before euthanasia. In addition, neuropathological studies were performed to investigate for cerebral bilirubin deposition as well as for signs of glial reactivity in brainstem structures involved in cardiorespiratory control. Results revealed that sustained and moderate HB: (i) decreased baseline respiratory rate and increased the time spent in apnea; (ii) blunted the cardiorespiratory inhibition normally observed during both laryngeal and pulmonary chemoreflexes; and (iii) increased heart rate in response to acute hypoxia. These acute physiological changes were concurrent with an activation of Alzheimer type II astrocytes throughout the brain, including the brainstem. Concomitantly, bilirubin deposits were observed in the leptomeninges, but not in brain parenchyma. While most cardiorespiratory alterations returned to normal 72 h after HB normalization, the expression of glial fibrillary acid protein (GFAP) and ionized calcium binding adaptor molecule 1 (Iba1) was still increased within the nucleus tractus solitarius. In conclusion, moderate and sustained HB in preterm lambs induced cardiorespiratory alterations, the latter of which were associated with neurohistopathological changes. These changes are indicative of an inflammatory response in the brainstem

  4. The PI3K signaling-mediated nitric oxide contributes to cardiovascular effects of angiotensin-(1-7) in the nucleus tractus solitarii of rats.

    PubMed

    Wu, Zhao-Tang; Ren, Chang-Zhen; Yang, Ya-Hong; Zhang, Ru-Wen; Sun, Jia-Cen; Wang, Yang-Kai; Su, Ding-Feng; Wang, Wei-Zhong

    2016-01-30

    Angiotensin-1-7 [Ang-(1-7)], acting via the Mas receptor in the central nervous system, is involved in the regulation of cardiovascular activity. Nitric oxide (NO) is implicated as an important modulator in the nucleus tractus solitarii (NTS), a key region involved in control of cardiovascular activity. The aim of the present study was to determine the role of phosphatidylinositol 3-kinase (PI3K) signaling in mediating the effect of Ang-(1-7) on NO generation in the NTS. In Sprague-Dawley rats, acute injection of Ang-(1-7) into the NTS significantly increased NO generation and neuronal/endothelial NO synthase (n/eNOS) activity, which were abolished by the selective Mas receptor antagonist d-Alanine-[Ang-(1-7)] (A-779), the PI3K inhibitor LY294002, or the Akt inhibitor triciribine (TCN). Western blotting analysis further demonstrated that Ang-(1-7) significantly increased levels of Akt/NOS phosphorylation in the NTS, and Ang-(1-7)-induced e/nNOS phosphorylation was antagonized by LY294002 or TCN. Furthermore, gene knockdown of PI3K by lentivirus containing small hairpin RNA in the NTS prevented the Ang-(1-7)-induced increases in NOS/Akt phosphorylation and NO production. The physiological (in vivo) experiments showed that pretreatment with the NOS inhibitor l-NAME, LY294002, or TCN abolished the decreases in blood pressure, heart rate, and renal sympathetic nerve activity induced by Ang-(1-7) injected into the NTS. Our findings suggest that nitric oxide release meditated by the Mas-PI3K-NOS signaling pathway is involved in the cardiovascular effects of Ang-(1-7) in the NTS.

  5. Administrative Implications of Mainstreaming. NAESP School Leadership Digest Second Series, Number 7. ERIC/CEM Research Analysis Series, Number 22.

    ERIC Educational Resources Information Center

    Coursen, David

    "Mainstreaming" is defined as a program whereby handicapped children are placed in regular classrooms for all or part of the school day, with steps taken to see that their special needs are satisfied within this arrangement. Key court decisions are cited because the implications of mainstreaming for contemporary education can be properly…

  6. Neural set point for the control of arterial pressure: role of the nucleus tractus solitarius

    PubMed Central

    2010-01-01

    Background Physiological experiments have shown that the mean arterial blood pressure (MAP) can not be regulated after chemo and cardiopulmonary receptor denervation. Neuro-physiological information suggests that the nucleus tractus solitarius (NTS) is the only structure that receives information from its rostral neural nuclei and from the cardiovascular receptors and projects to nuclei that regulate the circulatory variables. Methods From a control theory perspective, to answer if the cardiovascular regulation has a set point, we should find out whether in the cardiovascular control there is something equivalent to a comparator evaluating the error signal (between the rostral projections to the NTS and the feedback inputs). The NTS would function as a comparator if: a) its lesion suppresses cardiovascular regulation; b) the negative feedback loop still responds normally to perturbations (such as mechanical or electrical) after cutting the rostral afferent fibers to the NTS; c) perturbation of rostral neural structures (RNS) to the NTS modifies the set point without changing the dynamics of the elicited response; and d) cardiovascular responses to perturbations on neural structures within the negative feedback loop compensate for much faster than perturbations on the NTS rostral structures. Results From the control theory framework, experimental evidence found currently in the literature plus experimental results from our group was put together showing that the above-mentioned conditions (to show that the NTS functions as a comparator) are satisfied. Conclusions Physiological experiments suggest that long-term blood pressure is regulated by the nervous system. The NTS functions as a comparator (evaluating the error signal) between its RNS and the cardiovascular receptor afferents and projects to nuclei that regulate the circulatory variables. The mean arterial pressure (MAP) is regulated by the feedback of chemo and cardiopulmonary receptors and the baroreflex

  7. Energetic costs and implications of the intake of plant secondary metabolites on digestive and renal morphology in two austral passerines.

    PubMed

    Barceló, Gonzalo; Ríos, Juan Manuel; Maldonado, Karin; Sabat, Pablo

    2016-07-01

    Seed-eating birds have a diet of high nutritional value; however, they must cope with plant secondary metabolites (PSM). We postulated that the detoxification capacity of birds is associated with a metabolic cost, given that the organs responsible for detoxification significantly contribute to energetic metabolism. We used an experimental approach to assess the effects of phenol-enriched diets on two passerines with different feeding habits: the omnivorous rufous-collared sparrow (Zonotrichia capensis) and the granivorous common diuca-finch (Diuca diuca). The birds were fed with one of three diets: control diet, supplemented with tannic acid, or supplemented with Opuntia ficus-indica phenolic extract (a common food of the sparrow but not the finch). After 5 weeks of exposure to the diets, we measured basal metabolic rates (BMR), energy intake, glucuronic acid output and digestive and kidney structure. In both species, detoxification capacity expressed as glucuronic acid output was higher in individuals consuming phenol-enriched diets compared to the control diet. However, whereas sparrows increase energy intake and intestinal mass when feeding on phenol-enriched diets, finches had lower intestinal mass and energy intake remains stable. Furthermore, sparrows had higher BMR on phenol-enriched diets compared to the control group, whereas in the finches BMR remains unchanged. Interspecific differences in response to phenols intake may be determined by the dietary habits of these species. While both species can feed on moderate phenolic diets for 5 weeks, energy costs may differ due to different responses in food intake and organ structure to counteract the effects of PSM intake.

  8. Role of GABAergic neurones in the nucleus tractus solitarii in modulation of cardiovascular activity.

    PubMed

    Zubcevic, Jasenka; Potts, Jeffrey T

    2010-09-01

    GABAergic neurones are interspersed throughout the nucleus tractus solitarii (NTS), and their tonic activity is crucial to the maintenance of cardiorespiratory homeostasis. However, the mechanisms that regulate the magnitude of GABAergic inhibition in the NTS remain unknown. We hypothesized that the level of GABAergic inhibition is proportionally regulated by the level of excitatory synaptic input to the NTS from baroreceptors. Using the in situ working heart-brainstem preparation in normotensive and spontaneously hypertensive rats, we blocked GABA(A) receptor-mediated neurotransmission in the NTS with gabazine (a specific GABA(A) receptor antagonist) at two levels of perfusion pressure (low PP, 60-70 mmHg; and high PP, 105-125 mmHg) while monitoring the immediate changes in cardiorespiratory variables. In normotensive rats, gabazine produced an immediate bradycardia consistent with disinhibition of NTS circuit neurones that regulate heart rate (HR) which was proportional to the level of arterial pressure (HR at low PP, 57 +/- 9 beats min(1); at high PP, 177 +/- 9 beats min(1); P < 0.001), suggesting that GABAergic circuitry in the NTS modulating heart rate was arterial pressure dependent. In contrast, there was no significant difference in the magnitude of gabazine-induced bradycardia in spontaneously hypertensive rats at low or high PP (HR at low PP, 45 +/- 10 beats min(1); at high PP, 58 +/- 7 beats min(1)). With regard to thoracic sympathetic nerve activity (tSNA), at high PP there was a significant reduction in tSNA during the inspiratory (I) phase of the respiratory cycle, but only in the normotensive rat (tSNA = 18.7 +/- 10%). At low PP, gabazine caused an elevation of the postinspiration phase of tSNA in both normotensive (tSNA = 23.7 +/- 2.9%) and hypertensive rats (tSNA = 44.2 +/- 14%). At low PP, gabazine produced no change in tSNA during the mid-expiration phase in either rat strain, but at high PP we observed a significant reduction in the mid

  9. Substance P presynaptically depresses the transmission of sensory input to bronchopulmonary neurons in the guinea pig nucleus tractus solitarii

    PubMed Central

    Sekizawa, Shin-ichi; Joad, Jesse P; Bonham, Ann C

    2003-01-01

    Substance P modulates the reflex regulation of respiratory function by its actions both peripherally and in the CNS, particularly in the nucleus tractus solitarii (NTS), the first central site for synaptic contact of the lung and airway afferent fibres. There is considerable evidence that the actions of substance P in the NTS augment respiratory reflex output, but the precise effects on synaptic transmission have not yet been determined. Therefore, we determined the effects of substance P on synaptic transmission at the first central synapses by using whole-cell voltage clamping in an NTS slice preparation. Studies were performed on second-order neurons in the slice anatomically identified as receiving monosynaptic input from sensory nerves in the lungs and airways. This was done by the fluorescent labelling of terminal boutons after 1,1′-dioctadecyl-3,3,3′,3′-tetra-methylindocarbo-cyanine perchlorate (DiI) was applied via tracheal instillation. Substance P (1.0, 0.3 and 0.1 μM) significantly decreased the amplitude of excitatory postsynaptic currents (eEPSCs) evoked by stimulation of the tractus solitarius, in a concentration-dependent manner. The decrease was accompanied by an increase in the paired-pulse ratio of two consecutive eEPSCs, and a decrease in the frequency, but not the amplitude, of spontaneous EPSCs and miniature EPSCs, findings consistent with a presynaptic site of action. The effects were consistently and significantly attenuated by a neurokinin-1 (NK1) receptor antagonist (SR140333, 3 μM). The data suggest a new site of action for substance P in the NTS (NK1 receptors on the central terminals of sensory fibres) and a new mechanism (depression of synaptic transmission) for regulating respiratory reflex function. PMID:14561836

  10. In vitro digestive fluid extraction as a measure of the bioavailability of sediment-associated polycyclic aromatic hydrocarbons: Sources of variation and implications for partitioning models

    SciTech Connect

    Weston, D.P.; Mayer, L.M.

    1998-05-01

    In vitro extraction of contaminated sediments using the digestive fluid of a deposit-feeding polychaete has recently been proposed to study contaminant bioaccumulation mechanisms and perhaps to better quantify the bioavailable contaminant fraction. This approach was evaluated using digestive fluid from the polychaete Arenicola brasiliensis and six marine sediments containing both spiked radiolabeled polycyclic aromatic hydrocarbons (PAHs) and in situ-contaminated unlabeled PAHs. The proportion of total contaminant extracted by digestive fluid from each sediment varied from 22 to 71% and 13 to 52%, for phenanthrene and benzo[a]pyrene, respectively. The proportions of contaminant solubilized were inversely correlated with the sediments` organic carbon content. The extent of PAH solubilization among sediments by A. brasiliensis digestive fluid was highly correlated with that of digestive fluid from the echiuran Urechis caupo and appears to be a consequence of surfactant properties of the fluids rather than of their enzymatic activity. The proportion of PAHs solubilized in vitro was similar to in vivo measurements of solubilization for contaminant exposures lasting about 24 h. However, with continued exposure, in vivo PAH concentrations in the digestive fluid increased fivefold, suggesting that digestive fluid is retained in the gut longer than sediment and thus accumulates PAHs through sequential digestion of many gut volumes. This phenomenon may enhance contaminant fugacity in the gut and increase the potential for bioaccumulation or toxicity.

  11. Reversible alterations in epithelial cell turnover in digestive gland of winkles (Littorina littorea) exposed to cadmium and their implications for biomarker measurements.

    PubMed

    Zaldibar, B; Cancio, I; Marigómez, I

    2007-02-28

    In marine molluscs, the epithelium of the digestive gland is composed of two cell types, namely, digestive and basophilic cells. Under normal physiological conditions digestive cells outnumber basophilic cells, but under different stress situations the composition of the epithelium changes, basophilic cells apparently replace digestive cell. Winkles, Littorina littorea, were exposed to 1.25mg/l Cd for 20 days to provoke cell type replacement. Then, animals were depurated in clean seawater for 10 days to determine whether cell type replacement was reversible. Digestive glands were fixed in Carnoy and paraffin embedded for histological analysis. The volume densities of basophilic cells (Vv(BAS)) and digestive cells (Vv(DIG)) were calculated by stereology on hematoxylin-eosin stained sections. Vv(BAS) increased and Vv(DIG) decreased in Cd-exposed animals. After estimation of cell size and absolute cell numbers, these changes were attributed to digestive cell loss and concomitant basophilic cell hypertrophy but not to increased numbers of basophilic cells. Cell type composition and cell size almost fully returned to normal values after 10-day depuration. Accordingly, PCNA immunohistochemistry demonstrated that proliferating digestive cells were more abundant in winkles exposed to Cd and after 10-day depuration than in control specimens, suggesting that net digestive cell loss was accompanied by increased digestive cell proliferation. Thus, Cd-exposure seems to provoke an enhanced digestive cell turnover in order to cope with Cd detoxification. Intralysosomal accumulation of metals (autometallographied black silver deposits; BSD) was used as a biomarker of exposure to Cd and lysosomal structural changes as an effect biomarker to see whether cell type composition might have any effect on these endpoints. BSD formed around Cd ions, in digestive cell lysosomes of Cd-exposed winkles whereas basophilic cells appeared devoid of them. After depuration, BSD were less

  12. Digested disorder

    PubMed Central

    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

  13. Digestive Diseases

    MedlinePlus

    ... Digestive Diseases in the United States Healthy Moments Radio Listen to health tips from Dr. Rodgers in ... la salud en español Health Statistics Healthy Moments Radio Broadcast Clinical Trials For Health Care Professionals Community ...

  14. Glucan-rich diet is digested and taken up by the carnivorous sundew (Drosera rotundifolia L.): implication for a novel role of plant β-1,3-glucanases.

    PubMed

    Michalko, Jaroslav; Socha, Peter; Mészáros, Patrik; Blehová, Alžbeta; Libantová, Jana; Moravčíková, Jana; Matušíková, Ildikó

    2013-10-01

    Carnivory in plants evolved as an adaptation strategy to nutrient-poor environments. Thanks to specialized traps, carnivorous plants can gain nutrients from various heterotrophic sources such as small insects. Digestion in traps requires a coordinated action of several hydrolytic enzymes that break down complex substances into simple absorbable nutrients. Among these, several pathogenesis-related proteins including β-1,3-glucanases have previously been identified in digestive fluid of some carnivorous species. Here we show that a single acidic endo-β-1,3-glucanase of ~50 kDa is present in the digestive fluid of the flypaper-trapped sundew (Drosera rotundifolia L.). The enzyme is inducible with a complex plant β-glucan laminarin from which it releases simple saccharides when supplied to leaves as a substrate. Moreover, thin-layer chromatography of digestive exudates showed that the simplest degradation products (especially glucose) are taken up by the leaves. These results for the first time point on involvement of β-1,3-glucanases in digestion of carnivorous plants and demonstrate the uptake of saccharide-based compounds by traps. Such a strategy could enable the plant to utilize other types of nutritional sources e.g., pollen grains, fungal spores or detritus from environment. Possible multiple roles of β-1,3-glucanases in the digestive fluid of carnivorous sundew are also discussed.

  15. Chronic alcohol exposure alters transcription broadly in a key integrative brain nucleus for homeostasis: the nucleus tractus solitarius.

    PubMed

    Covarrubias, Maria Yolanda; Khan, Rishi L; Vadigepalli, Rajanikanth; Hoek, Jan B; Schwaber, James S

    2005-12-14

    Chronic exposure to alcohol modifies physiological processes in the brain, and the severe symptoms resulting from sudden removal of alcohol from the diet indicate that these modifications are functionally important. We investigated the gene expression patterns in response to chronic alcohol exposure (21-28 wk) in the rat nucleus tractus solitarius (NTS), a brain nucleus with a key integrative role in homeostasis and cardiorespiratory function. Using methods and an experimental design optimized for detecting transcriptional changes less than twofold, we found 575 differentially expressed genes. We tested these genes for significant associations with physiological functions and signaling pathways using Gene Ontology terms and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, respectively. Chronic alcohol exposure resulted in significant NTS gene regulation related to the general processes of synaptic transmission, intracellular signaling, and cation transport as well as specific neuronal functions including plasticity and seizure behavior that could be related to alcohol withdrawal symptoms. The differentially expressed genes were also significantly enriched for enzymes of lipid metabolism, glucose metabolism, oxidative phosphorylation, MAP kinase signaling, and calcium signaling pathways from KEGG. Intriguingly, many of the genes we found to be differentially expressed in the NTS are known to be involved in alcohol-induced oxidative stress and/or cell death. The study provides evidence of very extensive alterations of physiological gene expression in the NTS in the adapted state to chronic alcohol exposure.

  16. Hindbrain nucleus tractus solitarius glucagon-like peptide-1 receptor signaling reduces appetitive and motivational aspects of feeding

    PubMed Central

    Grill, Harvey J.

    2014-01-01

    Central glucagon-like peptide-1 receptor (GLP-1R) signaling reduces food intake by affecting a variety of neural processes, including those mediating satiation, motivation, and reward. While the literature suggests that separable neurons and circuits control these processes, this notion has not been adequately investigated. The intake inhibitory effects of GLP-1R signaling in the hindbrain medial nucleus tractus solitarius (mNTS) have been attributed to interactions with vagally transmitted gastrointestinal satiation signals that are also processed by these neurons. Here, behavioral and pharmacological techniques are used to test the novel hypothesis that the reduction of food intake following mNTS GLP-1R stimulation also results from effects on food-motivated appetitive behaviors. Results show that mNTS GLP-1R activation by microinjection of exendin-4, a long-acting GLP-1R agonist, reduced 1) intake of a palatable high-fat diet, 2) operant responding for sucrose under a progressive ratio schedule of reinforcement and 3) the expression of a conditioned place preference for a palatable food. Together, these data demonstrate that the intake inhibitory effects of mNTS GLP-1R signaling extend beyond satiation and include effects on food reward and motivation that are typically ascribed to midbrain and forebrain neurons. PMID:24944243

  17. The cough reflex is upregulated by lisinopril microinjected into the caudal nucleus tractus solitarii of the rabbit.

    PubMed

    Cinelli, Elenia; Bongianni, Fulvia; Pantaleo, Tito; Mutolo, Donatella

    2015-12-01

    We have previously shown that cough potentiation induced by intravenous administration of the AT1 receptor antagonist losartan is lower than that induced by the ACE inhibitor lisinopril in anesthetized and awake rabbits. Since losartan and lisinopril cross the blood-brain barrier, their central action on the cough reflex can be hypothesized. Mechanical stimulation of the tracheobronchial tree and citric acid inhalation were used to induce cough reflex responses in pentobarbital sodium-anesthetized, spontaneously breathing rabbits. Bilateral microinjections (30-50 nl) of losartan (5mM), lisinopril (1mM), bradykinin (0.05 mM), HOE-140 (0.2mM, a bradykinin B2 receptor antagonist) and CP-99,994 (1mM, an NK1 receptor antagonist) were performed into the caudal nucleus tractus solitarii, the predominant site of termination of cough-related afferents. Lisinopril, but not losartan increased the cough number. This effect was reverted by HOE-140 or CP-99,994. Cough potentiation was also induced by bradykinin. The results support for the first time a central protussive action of lisinopril mediated by an accumulation of bradykinin and substance P.

  18. EEG effects of microinjection of naloxone in the region of the nucleus tractus solitarius of the rat.

    PubMed

    Bronzino, J D; Oley, N; Kelly, M L; Cordova, C; Morgane, P J

    1983-07-18

    In recent years, we have carried out several studies on brainstem mechanisms associated with pain modulation. Of particular interest has been the region of the nucleus tractus solitarius (NTS) at the level of the area postrema (AP) in the dorsomedial medulla. This region has been found to be rich in opiate receptors and to be involved in pain modulation. Having previously demonstrated the EEG and behavioral effects of systemic administration of morphine, we initiated the present study to determine whether microinjection of naloxone directly into the region of the NTS will modify any or all of the EEG effects induced by subsequent systemic administration of morphine. Our results have shown that microinjections of naloxone into the region of the NTS block the cortical EEG synchronizing effects of systemically administered morphine. These results indicate that morphine-induced cortical EEG synchronization is mediated through the region of the NTS. This region may, therefore, comprise part of an opiate sensitive system which can influence cortical EEG activity.

  19. Activation of microglia and astrocytes in the nucleus tractus solitarius during ventilatory acclimatization to 10% hypoxia in unanesthetized mice.

    PubMed

    Tadmouri, A; Champagnat, J; Morin-Surun, M P

    2014-05-01

    Nucleus tractus solitarius (NTS) is the integrative sensory relay of autonomic functions in the brainstem. To explore the nonneuronal cellular basis of central chemosensitivity during the first 24 hr of ventilatory acclimatization to hypoxia (VHA), we have investigated glial activation markers in the NTS. Conscious mice (C57/BL6) were placed in a hermetic hypoxia chamber containing a plethysmograph to record ventilation. After 4 days of habituation to the normoxic environment, mice were subjected to physiological hypoxia (10% O2 ) for 1, 6, or 24 hr. To dissociate interactions between microglia and astrocytes, another group received daily minocycline, a microglia activation blocker. By immunochemical localization of astrocytes (GFAP), activated microglia (Cd11b), and total microglia (Iba-1), we identified an oxygen-sensing glial layer in the NTS, in which astrocytes are first activated after 1-6 hr of hypoxia, followed by microglia after 6-24 hr of hypoxia. Minocycline administration suppressed microglial activation and decreased astrocyte activation at 6 hr and VHA at 24 hr of hypoxia. These results suggest that astrocytes contribute to the neuronal response during the first hour of hypoxia, whereas microglial cells, via cross-talk with astrocytes, are involved in the VHA during the first 24 hr of acclimatization.

  20. Pathogenesis of Cognitive Dysfunction in Patients with Obstructive Sleep Apnea: A Hypothesis with Emphasis on the Nucleus Tractus Solitarius

    PubMed Central

    Daulatzai, Mak Adam

    2012-01-01

    OSA is characterized by the quintessential triad of intermittent apnea, hypoxia, and hypoxemia due to pharyngeal collapse. This paper highlights the upstream mechanisms that may trigger cognitive decline in OSA. Three interrelated steps underpin cognitive dysfunction in OSA patients. First, several risk factors upregulate peripheral inflammation; these crucial factors promote neuroinflammation, cerebrovascular endothelial dysfunction, and oxidative stress in OSA. Secondly, the neuroinflammation exerts negative impact globally on the CNS, and thirdly, important foci in the neocortex and brainstem are rendered inflamed and dysfunctional. A strong link is known to exist between neuroinflammation and neurodegeneration. A unique perspective delineated here underscores the importance of dysfunctional brainstem nuclei in etiopathogenesis of cognitive decline in OSA patients. Nucleus tractus solitarius (NTS) is the central integration hub for afferents from upper airway (somatosensory/gustatory), respiratory, gastrointestinal, cardiovascular (baroreceptor and chemoreceptor) and other systems. The NTS has an essential role in sympathetic and parasympathetic systems also; it projects to most key brain regions and modulates numerous physiological functions. Inflamed and dysfunctional NTS and other key brainstem nuclei may play a pivotal role in triggering memory and cognitive dysfunction in OSA. Attenuation of upstream factors and amelioration of the NTS dysfunction remain important challenges. PMID:23470865

  1. Digestive and appendicular soft-parts, with behavioural implications, in a large Ordovician trilobite from the Fezouata Lagerstätte, Morocco.

    PubMed

    Gutiérrez-Marco, Juan C; García-Bellido, Diego C; Rábano, Isabel; Sá, Artur A

    2017-01-10

    Trilobites were one of the most successful groups of marine arthropods during the Palaeozoic era, yet their soft-part anatomy is only known from a few exceptionally-preserved specimens found in a handful of localities from the Cambrian to the Devonian. This is because, even if the sclerotized appendages were not destroyed during early taphonomic stages, they are often overprinted by the three-dimensional, mineralised exoskeleton. Inferences about the ventral anatomy and behavioural activities of trilobites can also be derived from the ichnological record, which suggests that most Cruziana and Rusophycus trace fossils were possibly produced by the actions of trilobites. Three specimens of the asaphid trilobite Megistaspis (Ekeraspis) hammondi, have been discovered in the Lower Ordovician Fezouata Konservat-Lagerstätte of southern Morocco, preserving appendages and digestive tract. The digestive structures include a crop with digestive caeca, while the appendages display exopodal setae and slight heteropody (cephalic endopods larger and more spinose than thoracic and pygidial ones). The combination of these digestive structures and the heteropody has never been described together among trilobites, and the latter could assist in the understanding of the production of certain comb-like traces of the Cruziana rugosa group, which are extraordinarily abundant on the shallow marine shelves around Gondwana.

  2. Digestive and appendicular soft-parts, with behavioural implications, in a large Ordovician trilobite from the Fezouata Lagerstätte, Morocco

    PubMed Central

    Gutiérrez-Marco, Juan C.; García-Bellido, Diego C.; Rábano, Isabel; Sá, Artur A.

    2017-01-01

    Trilobites were one of the most successful groups of marine arthropods during the Palaeozoic era, yet their soft-part anatomy is only known from a few exceptionally-preserved specimens found in a handful of localities from the Cambrian to the Devonian. This is because, even if the sclerotized appendages were not destroyed during early taphonomic stages, they are often overprinted by the three-dimensional, mineralised exoskeleton. Inferences about the ventral anatomy and behavioural activities of trilobites can also be derived from the ichnological record, which suggests that most Cruziana and Rusophycus trace fossils were possibly produced by the actions of trilobites. Three specimens of the asaphid trilobite Megistaspis (Ekeraspis) hammondi, have been discovered in the Lower Ordovician Fezouata Konservat-Lagerstätte of southern Morocco, preserving appendages and digestive tract. The digestive structures include a crop with digestive caeca, while the appendages display exopodal setae and slight heteropody (cephalic endopods larger and more spinose than thoracic and pygidial ones). The combination of these digestive structures and the heteropody has never been described together among trilobites, and the latter could assist in the understanding of the production of certain comb-like traces of the Cruziana rugosa group, which are extraordinarily abundant on the shallow marine shelves around Gondwana. PMID:28071705

  3. Depressed GABA and glutamate synaptic signaling by 5-HT1A receptors in the nucleus tractus solitarii and their role in cardiorespiratory function

    PubMed Central

    Ostrowski, Tim D.; Ostrowski, Daniela; Hasser, Eileen M.

    2014-01-01

    Serotonin (5-HT), and its 5-HT1A receptor (5-HT1AR) subtype, is a powerful modulator of the cardiorespiratory system and its sensory reflexes. The nucleus tractus solitarii (nTS) serves as the first central station for visceral afferent integration and is critical for cardiorespiratory reflex responses. However, the physiological and synaptic role of 5-HT1ARs in the nTS is relatively unknown. In the present study, we examined the distribution and modulation of 5-HT1ARs on cardiorespiratory and synaptic parameters in the nTS. 5-HT1ARs were widely distributed to cell bodies within the nTS but not synaptic terminals. In anesthetized rats, activation of 5-HT1ARs by microinjection of the 5-HT1AR agonist 8-OH-DPAT into the caudal nTS decreased minute phrenic neural activity via a reduction in phrenic amplitude. In brain stem slices, 8-OH-DPAT decreased the amplitude of glutamatergic tractus solitarii-evoked excitatory postsynaptic currents, and reduced overall spontaneous excitatory nTS network activity. These effects persisted in the presence of GABAA receptor blockade and were antagonized by coapplication of 5-HT1AR blocker WAY-100135. 5-HT1AR blockade alone had no effect on tractus solitarii-evoked excitatory postsynaptic currents, but increased excitatory network activity. On the other hand, GABAergic nTS-evoked inhibitory postsynaptic currents did not change by activation of the 5-HT1ARs, but spontaneous inhibitory nTS network activity decreased. Blocking 5-HT1ARs tended to increase nTS-evoked inhibitory postsynaptic currents and inhibitory network activity. Taken together, 5-HT1ARs in the caudal nTS decrease breathing, likely via attenuation of afferent transmission, as well as overall nTS network activity. PMID:24671532

  4. TREATMENT OF MUSCLE MECHANOREFLEX DYSFUNCTION IN HYPERTENSION: EFFECTS OF L-ARGININE DIALYSIS IN THE NUCLEUS TRACTUS SOLITARII

    PubMed Central

    Leal, Anna K.; Mitchell, Jere H.; Smith, Scott A.

    2013-01-01

    The blood pressure response to exercise is exaggerated in hypertension. Recent evidence suggests that an overactive skeletal muscle mechanoreflex contributes significantly to this augmented circulatory responsiveness. Sensory information from the mechanoreflex is processed within the nucleus tractus solitarii (NTS) of the medulla oblongata. Normally, endogenously produced nitric oxide (NO) within the NTS attenuates the increase in mean arterial pressure (MAP) induced by mechanoreflex stimulation. Thus, it has been suggested that decreases in NTS-NO production underlie the generation of mechanoreflex dysfunction in hypertension. Supporting this postulate, it has been shown that blocking NO production within the NTS of normotensive rats reproduces the exaggerated pressor response elicited by mechanoreflex activation in hypertensive animals. What is not known is whether increasing NO production within the NTS of hypertensive rats mitigates mechanoreflex overactivity. In this study, the mechanoreflex was selectively activated by passively stretching hindlimb muscle before and after the dialysis of 1 and 10 μM L-arginine (a NO precursor) within the NTS of decerebrate normotensive Wistar Kyoto (WKY) and spontaneously hypertensive (SHR) rats. Stretch induced larger elevations in MAP in SHR compared to WKY. In both groups, dialysis of 1 μM L-arginine significantly attenuated the pressor response to stretch. However, at the 10 μM dose, L-arginine had no effect on the MAP response to stretch in WKY while it enhanced the response in SHR. The data demonstrate that increasing NO availability within the NTS using lower doses of L-arginine partially normalizes mechanoreflex dysfunction in hypertension whereas higher doses do not. The findings could prove valuable in the development of treatment options for mechanoreflex overactivity in this disease. PMID:23771911

  5. Leptin signaling in the medial nucleus tractus solitarius reduces food seeking and willingness to work for food.

    PubMed

    Kanoski, Scott E; Alhadeff, Amber L; Fortin, Samantha M; Gilbert, Jennifer R; Grill, Harvey J

    2014-02-01

    The adipose-derived hormone leptin signals in the medial nucleus tractus solitarius (mNTS) to suppress food intake, in part, by amplifying within-meal gastrointestinal (GI) satiation signals. Here we show that mNTS leptin receptor (LepRb) signaling also reduces appetitive and motivational aspects of feeding, and that these effects can depend on energy status. Using the lowest dose that significantly suppressed 3-h cumulative food intake, unilateral leptin (0.3 μg) administration to the mNTS (3 h before testing) reduced operant lever pressing for sucrose under increasing work demands (progressive ratio reinforcement schedule) regardless of whether animals were energy deplete (food restricted) or replete (ad libitum fed). However, in a separate test of food-motivated responding in which there was no opportunity to consume food (conditioned place preference (CPP) for an environment previously associated with a palatable food reward), mNTS leptin administration suppressed food-seeking behavior only in chronically food-restricted rats. On the other hand, mNTS LepRb signaling did not reduce CPP expression for morphine reinforcement regardless of energy status, suggesting that mNTS leptin signaling differentially influences motivated responding for food vs opioid reward. Overall results show that mNTS LepRb signaling reduces food intake and appetitive food-motivated responding independent of energy status in situations involving orosensory and postingestive contact with food, whereas food-seeking behavior independent of food consumption is only reduced by mNTS LepRb activation in a state of energy deficit. These findings reveal a novel appetitive role for LepRb signaling in the mNTS, a brain region traditionally linked with processing of meal-related GI satiation signals.

  6. Medial nucleus tractus solitarius oxytocin receptor signaling and food intake control: the role of gastrointestinal satiation signal processing

    PubMed Central

    Alhadeff, Amber L.; Grill, Harvey J.

    2015-01-01

    Central oxytocin (OT) administration reduces food intake and its effects are mediated, in part, by hindbrain oxytocin receptor (OT-R) signaling. The neural substrate and mechanisms mediating the intake inhibitory effects of hindbrain OT-R signaling are undefined. We examined the hypothesis that hindbrain OT-R-mediated feeding inhibition results from an interaction between medial nucleus tractus solitarius (mNTS) OT-R signaling and the processing of gastrointestinal (GI) satiation signals by neurons of the mNTS. Here, we demonstrated that mNTS or fourth ventricle (4V) microinjections of OT in rats reduced chow intake in a dose-dependent manner. To examine whether the intake suppressive effects of mNTS OT-R signaling is mediated by GI signal processing, rats were injected with OT to the 4V (1 μg) or mNTS (0.3 μg), followed by self-ingestion of a nutrient preload, where either treatment was designed to be without effect on chow intake. Results showed that the combination of mNTS OT-R signaling and GI signaling processing by preload ingestion reduced chow intake significantly and to a greater extent than either stimulus alone. Using enzyme immunoassay, endogenous OT content in mNTS-enriched dorsal vagal complex (DVC) in response to ingestion of nutrient preload was measured. Results revealed that preload ingestion significantly elevated endogenous DVC OT content. Taken together, these findings provide evidence that mNTS neurons are a site of action for hindbrain OT-R signaling in food intake control and that the intake inhibitory effects of hindbrain mNTS OT-R signaling are mediated by interactions with GI satiation signal processing by mNTS neurons. PMID:25740340

  7. Medial nucleus tractus solitarius oxytocin receptor signaling and food intake control: the role of gastrointestinal satiation signal processing.

    PubMed

    Ong, Zhi Yi; Alhadeff, Amber L; Grill, Harvey J

    2015-05-01

    Central oxytocin (OT) administration reduces food intake and its effects are mediated, in part, by hindbrain oxytocin receptor (OT-R) signaling. The neural substrate and mechanisms mediating the intake inhibitory effects of hindbrain OT-R signaling are undefined. We examined the hypothesis that hindbrain OT-R-mediated feeding inhibition results from an interaction between medial nucleus tractus solitarius (mNTS) OT-R signaling and the processing of gastrointestinal (GI) satiation signals by neurons of the mNTS. Here, we demonstrated that mNTS or fourth ventricle (4V) microinjections of OT in rats reduced chow intake in a dose-dependent manner. To examine whether the intake suppressive effects of mNTS OT-R signaling is mediated by GI signal processing, rats were injected with OT to the 4V (1 μg) or mNTS (0.3 μg), followed by self-ingestion of a nutrient preload, where either treatment was designed to be without effect on chow intake. Results showed that the combination of mNTS OT-R signaling and GI signaling processing by preload ingestion reduced chow intake significantly and to a greater extent than either stimulus alone. Using enzyme immunoassay, endogenous OT content in mNTS-enriched dorsal vagal complex (DVC) in response to ingestion of nutrient preload was measured. Results revealed that preload ingestion significantly elevated endogenous DVC OT content. Taken together, these findings provide evidence that mNTS neurons are a site of action for hindbrain OT-R signaling in food intake control and that the intake inhibitory effects of hindbrain mNTS OT-R signaling are mediated by interactions with GI satiation signal processing by mNTS neurons.

  8. Fear extinction can be made state-dependent on peripheral epinephrine: role of norepinephrine in the nucleus tractus solitarius.

    PubMed

    Rosa, Jessica; Myskiw, Jociane C; Furini, Cristiane R G; Sapiras, Gerson G; Izquierdo, Ivan

    2014-09-01

    We investigate whether the extinction of inhibitory avoidance (IA) learning can be subjected to endogenous state-dependence with systemic injections of epinephrine (E), and whether endogenous norepinephrine (NE) and the nucleus tractus solitarius (NTS)→locus coeruleus→hippocampus/amygdala (HIPP/BLA) pathway participate in this. Rats trained in IA were submitted to two sessions of extinction 24 h apart: In the first, the animals were submitted to a training session of extinction, and in the second they were tested for the retention of extinction. Saline or E were given i.p. immediately after the extinction training (post-extinction training injections) and/or 6 min before the extinction test (pre-extinction test). Post-extinction training E (50 or 100 μg/kg) induced a poor retrieval of extinction in the test session of this task unless an additional E injection (50 μg/kg) was given prior to the extinction test. This suggested state-dependence. Muscimol (0.01 μg/side) microinfused into the NTS prior to the extinction test session blocked E-induced state-dependence. Norepinephrine (NE, 1 μg/side) infused bilaterally into NTS restores the extinction impairment caused by post-extinction training i.p. E. In animals with bilateral NTS blockade induced by muscimol, NE (1 μg/side) given prior to the extinction test into the CA1 region of the dorsal hippocampus or into the basolateral amygdala restored the normal extinction levels that had been impaired by muscimol. These results suggest a role for the NTS→locus coeruleus→HIPP/BLA pathway in the retrieval of extinction, as it has been shown to have in the consolidation of inhibitory avoidance and of object recognition learning.

  9. Modulation of the cough reflex by antitussive agents within the caudal aspect of the nucleus tractus solitarii in the rabbit.

    PubMed

    Mutolo, Donatella; Bongianni, Fulvia; Cinelli, Elenia; Fontana, Giovanni A; Pantaleo, Tito

    2008-07-01

    We have previously shown that ionotropic glutamate receptors in the caudal portion of the nucleus tractus solitarii (NTS), especially in the commissural NTS, play a prominent role in the mediation of tracheobronchial cough and that substance P potentiates this reflex. This NTS region could be a site of action of some centrally acting antitussive agents and a component of a drug-sensitive gating mechanism of cough. To address these issues, we investigated changes in baseline respiratory activity and cough responses to tracheobronchial mechanical stimulation following microinjections (30-50 nl) of centrally acting antitussive drugs into the caudal NTS of pentobarbitone-anesthetized, spontaneously breathing rabbits. [D-Ala2,N-Me-Phe4,Gly5-ol]-enkephalin (DAMGO) and baclofen decreased baseline respiratory frequency because of increases in the inspiratory time only at the higher concentration employed (5 mM and 1 mM, respectively). DAMGO (0.5 mM) and baclofen (0.1 mM) significantly decreased cough number, peak abdominal activity, peak tracheal pressure, and increased cough-related total cycle duration. At the higher concentrations, these agents suppressed the cough reflex. The effects of these two drugs were counteracted by specific antagonists (10 mM naloxone and 25 mM CGP-35348, respectively). The neurokinin-1 (NK1) receptor antagonist CP-99,994 (10 mM) abolished cough responses, whereas the NK2 receptor antagonist MEN 10376 (5 mM) had no effect. The results indicate that the caudal NTS is a site of action of some centrally acting drugs and a likely component of a neural system involved in cough regulation. A crucial role of substance P release in the mediation of reflex cough is also suggested.

  10. Effect of hyperoxic exposure during early development on neurotrophin expression in the carotid body and nucleus tractus solitarii

    PubMed Central

    Chavez-Valdez, Raul; Mason, Ariel; Nunes, Ana R.; Northington, Frances J.; Tankersley, Clarke; Ahlawat, Rajni; Johnson, Sheree M.

    2012-01-01

    Synaptic activity can modify expression of neurotrophins, which influence the development of neuronal circuits. In the newborn rat, early hyperoxia silences the synaptic activity and input from the carotid body, impairing the development and function of chemoreceptors. The purpose of this study was to determine whether early hyperoxic exposure, sufficient to induce hypoplasia of the carotid body and decrease the number of chemoafferents, would also modify neurotrophin expression within the nucleus tractus solitarii (nTS). Rat pups were exposed to hyperoxia (fraction of inspired oxygen 0.60) or normoxia until 7 or 14 days of postnatal development (PND). In the carotid body, hyperoxia decreased brain-derived neurotrophic factor (BDNF) protein expression by 93% (P = 0.04) after a 7-day exposure, followed by a decrease in retrogradely labeled chemoafferents by 55% (P = 0.004) within the petrosal ganglion at 14 days. Return to normoxia for 1 wk after a 14-day hyperoxic exposure did not reverse this effect. In the nTS, hyperoxia for 7 days: 1) decreased BDNF gene expression by 67% and protein expression by 18%; 2) attenuated upregulation of BDNF mRNA levels in response to acute hypoxia; and 3) upregulated p75 neurotrophic receptor, truncated tropomyosin kinase B (inactive receptor), and cleaved caspase-3. These effects were not observed in the locus coeruleus (LC). Hyperoxia for 14 days also decreased tyrosine hydroxylase levels by 18% (P = 0.04) in nTS but not in the LC. In conclusion, hyperoxic exposure during early PND reduces neurotrophin levels in the carotid body and the nTS and shifts the balance of neurotrophic support from prosurvival to proapoptotic in the nTS, the primary brain stem site for central integration of sensory and autonomic inputs. PMID:22422797

  11. The effect of endomorphins on the release of 3H-norepinephrine from rat nucleus tractus solitarii slices.

    PubMed

    Al-Khrasani, Mahmoud; Elor, Guy; Yusuf Abbas, Mamode; Rónai, András Z

    2003-03-28

    We used two, 3-min field stimulation cycles 30 min apart (S1, S2) in 3H-norepinephrine-loaded, superfused rat nucleus tractus solitarii-dorsal motor vagal nucleus (NTS-DVN) slices. The stimulation-induced release was expressed as the area above the baseline. Drugs were introduced 12 min before S2 and drug actions were characterized in terms of alterations of S2/S1 ratios. The S2/S1 ratio was 1.047 (0.946-1.159, n = 4, geometric mean and 95% confidence interval) in controls and 0.336 (0.230-0.490, n = 3), 0.726 (0.590-0.892, n = 4), 0.613 (0.594-0.683, n = 4) and 0.665 (0.500-0.886, n = 4) in the presence of 10(-6) M clonidine, D-Ala(2),MePhe(4),Gly(5)-ol-enkephalin (DAMGO), endomorphin-1 (Tyr-Pro-Trp-Phe-NH(2), EM-1) and -2 (Tyr-Pro-Phe-Phe-NH(2), EM-2) [the latter two in the presence of 10(-4) M diprotin A, an inhibitor of dipeptidyl-aminopeptidase IV (DAP-IV) enzyme]. The effect of DAMGO at 10(-5) M was significantly higher than at 10(-6) M, whereas the effect of endomorphins did not differ at the two concentration levels. Diprotin A potentiated only very modestly the action of endomorphins. These data (a) confirm the presence of functional mu-opioid receptors in the vagal complex, (b) render it likely that the enzymic degradation of endomorphins is not a highly effective process in brain slices and (c) may suggest that the apparent ceiling in the effect of endomorphins might be related to their partial agonist property.

  12. Secondhand tobacco smoke exposure differentially alters nucleus tractus solitarius neurons at two different ages in developing non-human primates

    SciTech Connect

    Sekizawa, Shin-ichi; Joad, Jesse P.; Pinkerton, Kent E.; Bonham, Ann C.

    2010-01-15

    Exposing children to secondhand tobacco smoke (SHS) is associated with increased risk for asthma, bronchiolitis and SIDS. The role for changes in the developing CNS contributing to these problems has not been fully explored. We used rhesus macaques to test the hypothesis that SHS exposure during development triggers neuroplastic changes in the nucleus tractus solitarius (NTS), where lung sensory information related to changes in airway and lung function is first integrated. Pregnant monkeys were exposed to filtered air (FA) or SHS for 6 h/day, 5 days/week starting at 50-day gestational age. Mother/infant pairs continued the exposures postnatally to age 3 or 13 months, which may be equivalent to approximately 1 or 4 years of human age, respectively. Whole-cell recordings were made of second-order NTS neurons in transverse brainstem slices. To target the consequences of SHS exposure based on neuronal subgroups, we classified NTS neurons into two phenotypes, rapid-onset spiking (RS) and delayed-onset spiking (DS), and then evaluated intrinsic and synaptic excitabilities in FA-exposed animals. RS neurons showed greater cell excitability especially at age of 3 months while DS neurons received greater amplitudes of excitatory postsynaptic currents (EPSCs). Developmental neuroplasticity such as increases in intrinsic and synaptic excitabilities were detected especially in DS neurons. In 3 month olds, SHS exposure effects were limited to excitatory changes in RS neurons, specifically increases in evoked EPSC amplitudes and increased spiking responses accompanied by shortened action potential width. By 13 months, the continued SHS exposure inhibited DS neuronal activity; decreases in evoked EPSC amplitudes and blunted spiking responses accompanied by prolonged action potential width. The influence of SHS exposure on age-related and phenotype specific changes may be associated with age-specific respiratory problems, for which SHS exposure can increase the risk, such as SIDS

  13. Spatio-Temporal, Genotypic, and Environmental Effects on Plant Soluble Protein and Digestible Carbohydrate Content: Implications for Insect Herbivores with Cotton as an Exemplar.

    PubMed

    Deans, Carrie A; Behmer, Spencer T; Fiene, Justin; Sword, Gregory A

    2016-11-01

    Plant soluble protein and digestible carbohydrate content significantly affect insect herbivore fitness, but studies reporting plant protein and carbohydrate content are rare. Instead, the elements nitrogen and carbon often are used as surrogates for plant protein and digestible carbohydrate content, respectively. However, this is problematic for two reasons. First, carbon is found in all organic molecules, which precludes strong correlations with ecologically important dietary macronutrients (e.g., digestible carbohydrates, the primary energy source for most insect herbivores). Second, some elements (e.g., nitrogen) are present in both macronutrients (e.g., protein) and non-nutritive secondary compounds (e.g., alkaloids, protease inhibitors); in these cases N values would greatly overestimate protein available for an insect herbivore. Thus, the objective of this study was to explicitly document plant protein-carbohydrate content and assess its variation in cotton (Gossypium hirsutum and G. barbadense), which is a nutritional resource for a number of insect herbivores. We did this by measuring plant soluble protein (P) and digestible carbohydrate (C) content across seven plant tissues, five varieties, and two growing environments. Significant differences in P and C concentration, total macronutrient content (P + C), and P:C ratio were observed across plant tissues, plant age and environment; smaller differences were seen across plant genotype. Foliar tissues had higher total P + C content compared to reproductive tissues, except for developing seeds and developing flowers, which contained twice the total P + C content; these two tissues also had the highest P content. Our data show that even agricultural monocultures offer a highly heterogeneous protein-carbohydrate landscape for insect herbivores. Characterizing plant resources using nutritional currencies (e.g., protein and carbohydrates) that are ecologically and physiologically-relevant to insect

  14. Anaerobic Digestion.

    PubMed

    Liebetrau, Jan; Sträuber, Heike; Kretzschmar, Jörg; Denysenko, Velina; Nelles, Michael

    2017-04-09

    The term anaerobic digestion usually refers to the microbial conversion of organic material to biogas, which mainly consists of methane and carbon dioxide. The technical application of the naturally-occurring process is used to provide a renewable energy carrier and - as the substrate is often waste material - to reduce the organic matter content of the substrate prior to disposal.Applications can be found in sewage sludge treatment, the treatment of industrial and municipal solid wastes and wastewaters (including landfill gas utilization), and the conversion of agricultural residues and energy crops.For biorefinery concepts, the anaerobic digestion (AD) process is, on the one hand, an option to treat organic residues from other production processes. Concomitant effects are the reduction of organic carbon within the treated substance, the conversion of nitrogen and sulfur components, and the production of an energy-rich gas - the biogas. On the other hand, the multistep conversion of complex organic material offers the possibility of interrupting the conversion chain and locking out intermediates for utilization as basic material within the chemical industry.

  15. Digestive System (For Teens)

    MedlinePlus

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Digestive System KidsHealth > For Teens > Digestive System A A A ... out of the body as feces. About the Digestive System Every morsel of food we eat has to ...

  16. NPY and VGF Immunoreactivity Increased in the Arcuate Nucleus, but Decreased in the Nucleus of the Tractus Solitarius, of Type-II Diabetic Patients

    PubMed Central

    Saderi, Nadia; Salgado-Delgado, Roberto; Avendaño-Pradel, Rafael; Basualdo, Maria del Carmen; Ferri, Gian-Luca; Chávez-Macías, Laura; Escobar, Carolina; Buijs, Ruud M.

    2012-01-01

    Ample animal studies demonstrate that neuropeptides NPY and α-MSH expressed in Arcuate Nucleus and Nucleus of the Tractus Solitarius, modulate glucose homeostasis and food intake. In contrast is the absence of data validating these observations for human disease. Here we compare the post mortem immunoreactivity of the metabolic neuropeptides NPY, αMSH and VGF in the infundibular nucleus, and brainstem of 11 type-2 diabetic and 11 non-diabetic individuals. α-MSH, NPY and tyrosine hydroxylase in human brain are localized in the same areas as in rodent brain. The similar distribution of NPY, α-MSH and VGF indicated that these neurons in the human brain may share similar functionality as in the rodent brain. The number of NPY and VGF immuno positive cells was increased in the infundibular nucleus of diabetic subjects in comparison to non-diabetic controls. In contrast, NPY and VGF were down regulated in the Nucleus of the Tractus Solitarius of diabetic patients. These results suggest an activation of NPY producing neurons in the arcuate nucleus, which, according to animal experimental studies, is related to a catabolic state and might be the basis for increased hepatic glucose production in type-2 diabetes. PMID:22808091

  17. Nitric oxide and GABA mediate bi-directional cardiovascular effects of orexin in the nucleus tractus solitarii of rats.

    PubMed

    Shih, C-D; Chuang, Y-C

    2007-11-09

    The present study investigated the cardiovascular effects of orexin (OX)-A and OX-B in the nucleus tractus solitarii (NTS) and delineated the engagement of nitric oxide (NO) and GABA in OX-induced cardiovascular responses. In adult male Sprague-Dawley rats maintained under propofol anesthesia, microinjection bilaterally into the NTS of OX-A or OX-B evoked bi-directional cardiovascular effects in a dose-dependent manner. At a lower dose (5 pmol), OX-A or OX-B decreased systemic arterial pressure (SAP), heart rate (HR), and power density of the vasomotor components of SAP signals, our experimental index for sympathetic neurogenic vasomotor tone. At higher doses (>20 pmol), these two compounds elicited cardiovascular excitatory responses. These bi-directional cardiovascular effects of OX were abolished by co-injection of an OX(1) receptor antagonist, 1-(2-methylbenzoxazol-6-yl)-3-[1,5]naphthyridin-4-yl-urea hydrochloride (SB-334867, 0.75 nmol) or the OX(2) receptor antiserum (1:20). In addition, the vasodepressor effects of low dose (5 pmol) OX-A or OX-B in the NTS were attenuated by a nitric oxide synthase (NOS) inhibitor, N(G)-nitro-l-arginine methyl ester (l-NAME, 5 nmol), a neuronal nitric oxide synthase (nNOS) inhibitor, 7-nitroindazole (2.5 pmol) or the soluble guanylate cyclase (sGC) inhibitor, 1H-[1,2,4]oxadiazole[4,3-alpha]quinoxalin-1-one (250 pmol). The vasopressor effects of high dose (200 pmol) OX were reversed by co-administration with GABA(A) or GABA(B) receptor antagonist, bicuculline methiodine (10 pmol) or 2-hydroxy saclofen (100 pmol), or l-NAME (5 nmol). Our results indicate that OX-A or OX-B elicited bi-directional cardiovascular effects via OX receptor-dependent mechanisms. The vasodepressor effects of OX were induced by the nNOS-derived NO and activation of sGC-associated signaling pathway, whereas the vasopressor effects were mediated by interaction with GABAergic or nitrergic neurotransmission in the NTS.

  18. An ionic current model for neurons in the rat medial nucleus tractus solitarii receiving sensory afferent input.

    PubMed Central

    Schild, J H; Khushalani, S; Clark, J W; Andresen, M C; Kunze, D L; Yang, M

    1993-01-01

    1. Neurons from a horizontal slice of adult rat brainstem were examined using intracellular recording techniques. Investigations were restricted to a region within the nucleus tractus solitarii, medial to the solitary tract and centred on the obex (mNTS). Previous work has shown this restricted area of the NTS to contain the greatest concentration of aortic afferent baroreceptor terminal fields. Electrical stimulation of the tract elicited short-latency excitatory postsynaptic potentials in all neurons. 2. mNTS neurons were spontaneously active with firing frequencies ranging between 1 and 10 Hz, at resting potentials of -65 to -45 mV. These neurons did not exhibit spontaneous bursting activity. 3. Depolarizing current injection immediately evoked a finite, high-frequency spike discharge which rapidly declined to a lower steady-state level (i.e. spike frequency adaptation, SFA). Increasing depolarizations produced a marked increase in the peak instantaneous frequency but a much smaller increase in the steady-state firing level. 4. Conditioning with a hyperpolarizing prepulse resulted in a prolonged delay of up to 600 ms before the first action potential (i.e. delayed excitation, DE) with an attendant decrease in peak discharge rates. DE was modulated by both the magnitude and duration of the prestimulus hyperpolarization, as well as the magnitude of the depolarizing stimulus. Tetrodotoxin (TTX) eliminated spike discharge but had little effect on the ramp-like membrane depolarization characteristic of DE. 5. We have developed a mathematical model for mNTS neurons to facilitate our understanding of the interplay between the underlying ionic currents. It consists of a comprehensive membrane model of the Hodgkin-Huxley type coupled with a fluid compartment model describing cytoplasmic [Ca2+]i homeostasis. 6. The model suggests that (a) SFA is caused by an increase in [Ca2+]i which activates the outward K+ current, IK,Ca, and (b) DE results from the competitive

  19. Engineering Digestion: Multiscale Processes of Food Digestion.

    PubMed

    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.

  20. An enkephalin-containing pathway from nucleus tractus solitarius to the pressor area of the rostral ventrolateral medulla of the rabbit.

    PubMed

    Morilak, D A; Somogyi, P; McIlhinney, R A; Chalmers, J

    1989-01-01

    A technique combining retrograde tracing of wheat germ-conjugated gold particles with immunocytochemical demonstration of enkephalin-containing neurons was used to study intramedullary enkephalin-containing pathways to the pressor area of the rostral ventrolateral medulla in rabbits. The rostral ventrolateral medulla represents a main source of bulbospinal sympathoexcitatory neurons, and is critical to the tonic and reflex control of blood pressure. Firstly, the distribution of enkephalin-positive neurons and terminal fibres in rabbit medulla were described, with special reference to a moderately dense terminal plexus in the rostral ventrolateral medulla. Then, retrograde tracing studies were conducted; the rostral ventrolateral medullary pressor region was first localized by injection of L-glutamate (25 nmol in 50 nl). Slow (30-min) injections of wheat germ-gold (1.00 microliter) were then made at the same coordinates, resulting in a restricted injection site corresponding to the C1 pressor area, verified by the presence of tyrosine hydroxylase- and neuropeptide Y-containing neurons. Transported gold was revealed by silver reduction, and enkephalin immunoreactive cells were revealed by immunocytochemistry. Enkephalin-positive gold-containing neurons were found primarily in the nucleus tractus solitarius, especially in the commissural and medial intermediate subnuclei. Cells in the nucleus tractus solitarius containing other transmitters (substance P. galanin, neuropeptide Y and catecholamines) did not show the same degree or pattern of double-labelling, suggesting that the transport was not due to non-specific silver reduction or spread from the pipette track. The potential importance of this endogenous intramedullary opiate system is discussed in terms of medullary control of the cardiovascular system. It is hypothesized that this opiate projection from the nucleus tractus solitarius to the rostral ventrolateral medulla could play an important modulatory function

  1. Implication of milling methods, thermal treatment, and particle size of feed in layers on mineral digestibility and retention of minerals in egg contents.

    PubMed

    Hafeez, A; Mader, A; Ruhnke, I; Röhe, I; Boroojeni, F Goodarzi; Yousaf, M S; Männer, K; Zentek, J

    2015-02-01

    Feed production with different milling methods, thermal treatment, and particle size may influence mineral digestibility and retention in eggs. The present study investigated the impact of roller (R) and hammer (H) mills, mash (M) and expandate (E) with fine (F) and coarse (C) particle sizes, on apparent ileal absorption (AIA) and apparent total digestibility (ATD) and retention of calcium, phosphorus, magnesium, zinc, manganese, copper and iron in yolk, albumen, and shell. A total of 384 hens (Lohmann Brown), 19 weeks old, were assigned using a randomized design with a 2×2×2 factorial arrangement. Eight experimental diets were offered ad libitum during the whole experimental period and one week before for diet adaption. The AIA of magnesium, zinc, copper, and iron was higher in treatment R in comparison with treatment H (P<0.01, P≤0.03, P<0.01 and P<0.01, respectively). The AIA of magnesium was higher in treatment M than treatment E (P<0.01). The AIA of magnesium was higher in treatment C in comparison with treatment F (P≤0.05) due to particle size. The ATD of copper and iron was higher in treatment R than treatment H (P<0.01 and P≤0.03, respectively). The ATD was higher for phosphorus and lower for iron in treatment F than treatment C (P≤0.05 and P≤0.02. respectively). The copper concentration in yolk and albumen was higher in treatment C than treatment F (P<0.01 and P≤0.03, respectively). Besides a few overall interactions, the AIA and ATD of copper and manganese were lower in H+M group than R+M group (P≤0.05). The ATD of iron was higher in the M+C group compared to the M+F group (P<0.01), whereas the albumen zinc concentration was higher in the E+C group than E+F group (P < 0.01). In conclusion, the feed produced by hammer mill had negative effects on AIA and ATD for trace elements in particular, but mineral concentrations in egg contents were mostly comparable for all treatments. Therefore, milling methods, thermal treatment, and particle sizes

  2. Effect of mastication on lipid bioaccessibility of almonds in a randomized human study and its implications for digestion kinetics, metabolizable energy, and postprandial lipemia1234

    PubMed Central

    Grundy, Myriam ML; Grassby, Terri; Mandalari, Giuseppina; Waldron, Keith W; Butterworth, Peter J; Berry, Sarah EE

    2015-01-01

    Background: The particle size and structure of masticated almonds have a significant impact on nutrient release (bioaccessibility) and digestion kinetics. Objectives: The goals of this study were to quantify the effects of mastication on the bioaccessibility of intracellular lipid of almond tissue and examine microstructural characteristics of masticated almonds. Design: In a randomized, subject-blind, crossover trial, 17 healthy subjects chewed natural almonds (NAs) or roasted almonds (RAs) in 4 separate mastication sessions. Particle size distributions (PSDs) of the expectorated boluses were measured by using mechanical sieving and laser diffraction (primary outcome). The microstructure of masticated almonds, including the structural integrity of the cell walls (i.e., dietary fiber), was examined with microscopy. Lipid bioaccessibility was predicted by using a theoretical model, based on almond particle size and cell dimensions, and then compared with empirically derived release data. Results: Intersubject variations (n = 15; 2 subjects withdrew) in PSDs of both NA and RA samples were small (e.g., laser diffraction; CV: 12% and 9%, respectively). Significant differences in PSDs were found between these 2 almond forms (P < 0.05). A small proportion of lipid was released from ruptured cells on fractured surfaces of masticated particles, as predicted by using the mathematical model (8.5% and 11.3% for NAs and RAs, respectively). This low percentage of lipid bioaccessibility is attributable to the high proportion (35–40%) of large particles (>500 μm) in masticated almonds. Microstructural examination of the almonds indicated that most intracellular lipid remained undisturbed in intact cells after mastication. No adverse events were recorded. Conclusions: Following mastication, most of the almond cells remained intact with lipid encapsulated by cell walls. Thus, most of the lipid in masticated almonds is not immediately bioaccessible and remains unavailable for

  3. Morphological and genomic comparisons of Hawaiian and Japanese Black-footed Albatrosses (Phoebastria nigripes) using double digest RADseq: implications for conservation.

    PubMed

    Dierickx, Elisa G; Shultz, Allison J; Sato, Fumio; Hiraoka, Takashi; Edwards, Scott V

    2015-08-01

    Evaluating the genetic and demographic independence of populations of threatened species is important for determining appropriate conservation measures, but different technologies can yield different conclusions. Despite multiple studies, the taxonomic status and extent of gene flow between the main breeding populations of Black-footed Albatross (Phoebastria nigripes), a Near-Threatened philopatric seabird, are still controversial. Here, we employ double digest RADseq to quantify the extent of genomewide divergence and gene flow in this species. Our genomewide data set of 9760 loci containing 3455 single nucleotide polymorphisms yielded estimates of genetic diversity and gene flow that were generally robust across seven different filtering and sampling protocols and suggest a low level of genomic variation (θ per site = ∼0.00002-0.00028), with estimates of effective population size (N e = ∼500-15 881) falling far below current census size. Genetic differentiation was small but detectable between Japan and Hawaii (F ST ≈ 0.038-0.049), with no F ST outliers. Additionally, using museum specimens, we found that effect sizes of morphological differences by sex or population rarely exceeded 4%. These patterns suggest that the Hawaiian and Japanese populations exhibit small but significant differences and should be considered separate management units, although the evolutionary and adaptive consequences of this differentiation remain to be identified.

  4. Identification, expression and antibacterial activity of a tachylectin-related homolog in amphioxus Branchiostoma belcheri with implications for involvement of the digestive system in acute phase response.

    PubMed

    Ju, Lingyan; Zhang, Shicui; Liang, Yujun; Sun, Xuemei

    2009-02-01

    Tachylectin-related proteins have been identified in various organisms from slime molds to sponges to bony fish, yet little is known to date about it in protochordate amphioxus, an important organism occupying a nodal position from invertebrates to vertebrates. Moreover, if the protein acts as an immune-relevant molecule remains controversial. Here we demonstrated the presence of a tachylectin-related gene in Branchiostoma belcheri. The predicted gene product, termed BbTL, consists of 305 amino acids with a putative N-terminal signal peptide and 6 tachylectin-typical tandem repeats of 30-33 amino acids. In situ hybridization histochemistry indicates a tissue-specific expression pattern of BbTL in adult amphioxus with the most abundant expression in the hepatic caecum and hind-gut. Quantitative real-time PCR reveals that challenge with LPS results in a significant up-regulation of BbTL expression in the guts. In addition, the recombinant BbTL expressed in Pichia pastoris is able to inhibit the growth of Gram-negative bacterium Escherichia coli in a dose-dependent manner. All these suggest that BbTL, like most other tachylectin-related proteins, is involved in the host immune defense, and the digestive system of B. belcheri appears the major immune tissue responding to LPS challenge.

  5. Morphological and genomic comparisons of Hawaiian and Japanese Black-footed Albatrosses (Phoebastria nigripes) using double digest RADseq: implications for conservation

    PubMed Central

    Dierickx, Elisa G; Shultz, Allison J; Sato, Fumio; Hiraoka, Takashi; Edwards, Scott V

    2015-01-01

    Evaluating the genetic and demographic independence of populations of threatened species is important for determining appropriate conservation measures, but different technologies can yield different conclusions. Despite multiple studies, the taxonomic status and extent of gene flow between the main breeding populations of Black-footed Albatross (Phoebastria nigripes), a Near-Threatened philopatric seabird, are still controversial. Here, we employ double digest RADseq to quantify the extent of genomewide divergence and gene flow in this species. Our genomewide data set of 9760 loci containing 3455 single nucleotide polymorphisms yielded estimates of genetic diversity and gene flow that were generally robust across seven different filtering and sampling protocols and suggest a low level of genomic variation (θ per site = ∼0.00002–0.00028), with estimates of effective population size (Ne = ∼500–15 881) falling far below current census size. Genetic differentiation was small but detectable between Japan and Hawaii (FST ≈ 0.038–0.049), with no FST outliers. Additionally, using museum specimens, we found that effect sizes of morphological differences by sex or population rarely exceeded 4%. These patterns suggest that the Hawaiian and Japanese populations exhibit small but significant differences and should be considered separate management units, although the evolutionary and adaptive consequences of this differentiation remain to be identified. PMID:26240604

  6. Livestock Anaerobic Digester Database

    EPA Pesticide Factsheets

    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.

  7. Your Digestive System (For Kids)

    MedlinePlus

    ... Room? What Happens in the Operating Room? Your Digestive System KidsHealth > For Kids > Your Digestive System A A ... the flush we were talking about! Dig That Digestive System You can help your digestive system by drinking ...

  8. Bibliotherapy. ERIC Digest.

    ERIC Educational Resources Information Center

    Aiex, Nola Kortner

    This digest deals with bibliotherapy, the practice of healing through books. The digest discusses whether bibliotherapy works, when it should be used, who should conduct it, and how it should be used. The digest concludes with five guidelines for conducting bibliotherapy. (RS)

  9. Teaching and Learning Economics. ERIC Digest.

    ERIC Educational Resources Information Center

    Seiter, David M.

    This ERIC Digest on economics education discusses: (1) the economic literacy of secondary school students; (2) the improvement of the economic curriculum; (3) the improvement of social studies teachers' training and teaching methods; and (4) the implications of improved economics education. A national survey sponsored by the Joint Council on…

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

    PubMed

    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.

  11. (Methane digester). Final report

    SciTech Connect

    Waybright, R.C.

    1981-01-01

    The purpose of the grant was to construct and operate a methane digester for dairy manure involving the latest state-of-the-art technics. The first step taken was to empty out the existing digester to evaluate its performance and to gain ideas of how to build the next digester so it would operate more efficiently. Next, the design criteria was set up in order to eliminate some problems involved with the first digester and also new ideas as to how to build the next one without a protective building and testing simplified construction technics. After this the digester construction was started with the completion date in late January. The digester was then filled and operated at different temperatures attempting to achieve the optimum operating range.

  12. Anaerobic digestion process

    SciTech Connect

    Ishida, M.; Haga, R.; Odawara, Y.

    1982-10-19

    An algae culture grown on the water from the digested slurry of a biogasification plant serves as a means of removing CO/sub 2/ from the methane stream while purifying the wastewater and providing more biomass for the anaerobic digestion plant. Tested on a sewage-sludge digestion system, the proposed process improved the methane yield by 32% and methane concentration by 53-98 vol % while lowering the concentration of nitrogen and phosphorus in the final water.

  13. Anaerobic Digestion and its Applications

    EPA Science Inventory

    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...

  14. Kappa-Opioid Receptors in the Caudal Nucleus Tractus Solitarius Mediate 100 Hz Electroacupuncture-Induced Sleep Activities in Rats

    PubMed Central

    Cheng, Chiung-Hsiang; Yi, Pei-Lu; Chang, Han-Han; Tsai, Yi-Fong; Chang, Fang-Chia

    2012-01-01

    Previous results demonstrated that 10 Hz electroacupuncture (EA) of Anmian acupoints in rats during the dark period enhances slow wave sleep (SWS), which involves the induction of cholinergic activity in the caudal nucleus tractus solitarius (NTS) and subsequent activation of opioidergic neurons and μ-receptors. Studies have shown that different kinds of endogenous opiate peptides and receptors may mediate the consequences of EA with different frequencies. Herein, we further elucidated that high-frequency (100 Hz)-EA of Anmian enhanced SWS during the dark period but exhibited no direct effect on rapid eye movement (REM) sleep. High-frequency EA-induced SWS enhancement was dose-dependently blocked by microinjection of naloxone or κ-receptor antagonist (nor-binaltorphimine) into the caudal NTS, but was affected neither by μ- (naloxonazine) nor δ-receptor antagonists (natatrindole), suggesting the role of NTS κ-receptors in the high-frequency EA-induced SWS enhancement. Current and previous results depict the opioid mechanisms of EA-induced sleep. PMID:22454676

  15. Effect of Vestibulosympathetic Reflex and Baroreflex on Expression of pERK in the Nucleus Tractus Solitarius following Acute Hypotension in Conscious Rats.

    PubMed

    Jiang, Xian; Lan, Yan; Jin, Yuan-Zhe; Park, Joo Young; Park, Byung Geon; Ameer, Abdul Nasir; Park, Byung Rim

    2014-08-01

    Control of blood pressure is maintained by the interaction between the arterial baroreflex and vestibulosympathetic reflex during postural changes. In this study, the contributions of vestibular receptors and baroreceptors to the maintenance of blood pressure following acute hypotension were compared in terms of phosphorylated extracellular regulated protein kinase (pERK) expression in the nucleus tractus solitaries (NTS). Expression of pERK in the NTS was measured in conscious rats that had undergone bilateral labyrinthectomy (BL) and/or sinoaortic denervation (SAD) 5, 10, 20, and 40 min following acute hypotension induced by sodium nitroprusside (SNP) infusion. Expression of pERK increased significantly in the NTS in the control group following SNP infusion, and the expression peaked at 10 min after SNP infusion. The number of pERK positive neurons increased following SNP infusion in BL, SAD, and BL+SAD groups, although the increase was smaller than in control group. The BL group showed a relatively higher reduction in pERK expression than the SAD group, and the pERK expression in the NTS was localized to the caudal portion of the nuclei in the BL and SAD groups. These results suggest that the vestibular receptors may play a key role in maintaining blood pressure following acute hypotension; thus, the vestibular system may contribute to compensate for orthostatic hypotension.

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

    PubMed

    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.

  17. Horse manure as feedstock for anaerobic digestion.

    PubMed

    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.

  18. Cardiovascular afferents cause the release of 5-HT in the nucleus tractus solitarii; this release is regulated by the low- (PMAT) not the high-affinity transporter (SERT)

    PubMed Central

    Hosford, Patrick S; Millar, Julian; Ramage, Andrew G

    2015-01-01

    Key points The nucleus tractus solitarii (NTS) integrates visceral afferent information essential for cardiovascular haemostasis. Using fast-cyclic voltammetry in anaesthetized rats, 5-HT (serotonin) release was detected in NTS in response to activation of these afferents. Removal of 5-HT from the extracellular space is usually regulated by the low-capacity, high-affinity 5-HT transporter (5-HTT/SERT). The present data demonstrate that 5-HT removal in the NTS is regulated by the plasma membrane monoamine transporter (PMAT), a high-capacity, low-affinity transporter. The present data also demonstrate that the 5-HT released by afferent activation comes from at least two different sources. It is suggested that one of these sources is the afferents themselves. These results demonstrate a physiological role for the low-affinity uptake transporter in the regulation of 5-HT concentration in NTS. Abstract The nucleus tractus solitarii (NTS) integrates inputs from cardiovascular afferents and thus is crucial for cardiovascular homeostasis. These afferents primarily release glutamate, although 5-HT has also been shown to play a role in their actions. Using fast-cyclic voltammetry, an increase in 5-HT concentrations (range 12–50 nm) could be detected in the NTS in anaesthetized rats in response to electrical stimulation of the vagus and activation of cardiopulmonary, chemo- and baroreceptor reflexes. This 5-HT signal was not potentiated by the serotonin transporter (SERT) or the noradrenaline transporter (NET) inhibitors citalopram and desipramine (1 mg kg−1). However, decynium-22 (600 μg kg−1), an organic cation 3 transporter (OCT3)/plasma membrane monoamine transporter (PMAT) inhibitor, increased the 5-HT signal by 111 ± 21% from 29 ± 10 nm. The effectiveness of these inhibitors was tested against the removal time of 5-HT and noradrenaline applied by microinjection to the NTS. Citalopram and decynium-22 attenuated the removal of 5-HT but not

  19. Chronic passive cigarette smoke exposure augments bronchopulmonary C-fibre inputs to nucleus tractus solitarii neurones and reflex output in young guinea-pigs

    PubMed Central

    Mutoh, T; Joad, J P; Bonham, A C

    2000-01-01

    Children chronically exposed to environmental tobacco smoke (passive cigarette smoke) have more wheeze, cough, bronchoconstriction, airway hyper-reactivity and mucous secretion, which may result, in part, from stimulation of the vagal bronchopulmonary C-fibre reflex. Environmental tobacco smoke increases the sensitivity of bronchopulmonary C-fibre endings, but the physiological relevance of this sensitization is unknown. If this exposure augments the reflex responses via a central mechanism, then the responses of higher-order neurones in the reflex pathway and some components of the reflex output should also be augmented. Guinea-pigs were chronically exposed to sidestream tobacco smoke (surrogate for environmental tobacco smoke) or filtered air for 5 days week−1 from age 1 to 6 weeks (age equivalent of human childhood) and were then anaesthetized, paralysed, ventilated and prepared with pneumothoraces. Baseline and left atrial capsaicin (0.5 and 2.0 μg kg−1)- evoked changes in the impulse activity of vagal C-fibre-activated neurones in nucleus tractus solitarii (NTS), phrenic nerve activity, tracheal pressure, arterial blood pressure and heart rate were compared in the two groups. Sidestream smoke exposure significantly augmented the peak (P = 0.02) and duration (P = 0.01) of the NTS neuronal responses and the prolongation of expiratory time (P = 0.003) at the higher capsaicin dose. Thus, the sensitization of the bronchopulmonary C-fibre endings by chronic exposure to sidestream tobacco smoke is transmitted to the NTS and is associated with a prolonged reflexively evoked expiratory apnoea. The findings may help to explain some related respiratory symptoms in children and be a factor in sudden infant death syndrome. PMID:10673557

  20. Localization and function of the Kv3.1b subunit in the rat medulla oblongata: focus on the nucleus tractus solitarii.

    PubMed

    Dallas, Mark L; Atkinson, Lucy; Milligan, Carol J; Morris, Neil P; Lewis, David I; Deuchars, Susan A; Deuchars, Jim

    2005-02-01

    The voltage-gated potassium channel subunit Kv3.1 confers fast firing characteristics to neurones. Kv3.1b subunit immunoreactivity (Kv3.1b-IR) was widespread throughout the medulla oblongata, with labelled neurones in the gracile, cuneate and spinal trigeminal nuclei. In the nucleus of the solitary tract (NTS), Kv3.1b-IR neurones were predominantly located close to the tractus solitarius (TS) and could be GABAergic or glutamatergic. Ultrastructurally, Kv3.1b-IR was detected in NTS terminals, some of which were vagal afferents. Whole-cell current-clamp recordings from neurones near the TS revealed electrophysiological characteristics consistent with the presence of Kv3.1b subunits: short duration action potentials (4.2 +/- 1.4 ms) and high firing frequencies (68.9 +/- 5.3 Hz), both sensitive to application of TEA (0.5 mm) and 4-aminopyridine (4-AP; 30 mum). Intracellular dialysis of an anti-Kv3.1b antibody mimicked and occluded the effects of TEA and 4-AP in NTS and dorsal column nuclei neurones, but not in dorsal vagal nucleus or cerebellar Purkinje cells (which express other Kv3 subunits, but not Kv3.1b). Voltage-clamp recordings from outside-out patches from NTS neurones revealed an outward K(+) current with the basic characteristics of that carried by Kv3 channels. In NTS neurones, electrical stimulation of the TS evoked EPSPs and IPSPs, and TEA and 4-AP increased the average amplitude and decreased the paired pulse ratio, consistent with a presynaptic site of action. Synaptic inputs evoked by stimulation of a region lacking Kv3.1b-IR neurones were not affected, correlating the presence of Kv3.1b in the TS with the pharmacological effects.

  1. Injections of Galanin-Like Peptide directly into the nucleus of the tractus solitarius (NTS) reduces food intake and body weight but increases metabolic rate and plasma leptin.

    PubMed

    Sergeant, Lindy; Rodriguez-Dimitrescu, Carla; Barney, Christopher C; Fraley, Gregory S

    2016-12-29

    Galanin-Like Peptide (GALP) is a hypothalamic neuromediator of metabolism and reproduction. GALP is known to stimulate reproduction and alter food intake and body weight in multiple species. The regulation of body weight involves control of both energy intake and energy expenditure. Since GALP is known to alter food intake - possibly via the autonomic nervous system - we first hypothesized that GALP would increase metabolic rate. First, male Sprague-Dawley rats were implanted with intracerebroventricular (ICV) cannulae and abdominal radiotelemetry temperature transmitters. Following ICV injection with either 5nmol GALP or vehicle, the oxygen consumption of each rat was monitored for 8h. Food intake, core temperature, and general motor activity were monitored for 24h. GALP significantly increased oxygen consumption, an indirect estimator of metabolic rate, without having any significant effect on motor activity. Compared to controls, GALP increased core body temperature during the photophase and reduced food intake over the 24h period following injection. ICV GALP also increased plasma levels of luteinizing hormone (LH). A second group of male Sprague-Dawley rats were implanted with abdominal transmitters and given injections of GALP directly into the nucleus of the tractus solitarius (NTS). These injections resulted in a significant reduction in food intake, and a significant increase in both oxygen consumption and core body temperature compared to vehicle injections. Direct injections of GALP into the NTS compared to vehicle also resulted in a significant increase in plasma leptin levels, but not LH levels. GALP appears to increase energy expenditure in addition to decreasing energy input by actions within the NTS and thus may play an important role in the hypothalamic regulation of body weight.

  2. Neuronal nitric oxide synthase expression is lower in areas of the nucleus tractus solitarius excited by skeletal muscle reflexes in hypertensive rats

    PubMed Central

    Mizuno, Masaki; Downey, Ryan M.; Squiers, John J.; Squiers, Kathryn E.; Smith, Scott A.

    2013-01-01

    The functions of the skeletal muscle exercise pressor reflex (EPR) and its mechanically sensitive component are augmented in hypertension producing exaggerated increases in blood pressure during exercise. Afferent information from the EPR is processed in the nucleus tractus solitarius (NTS). Within the NT, nitric oxide (NO), produced via l-arginine oxidation by neuronal nitric oxide synthase (nNOS), buffers the pressor response to EPR activation. Therefore, EPR overactivity may manifest as a decrease in NO production due to reductions in nNOS. We hypothesized that nNOS protein expression is lower in the NTS of spontaneously hypertensive (SHR) compared with normotensive Wistar-Kyoto (WKY) rats. Further, we examined whether nNOS is expressed with FOS, a marker of neuronal excitation induced by EPR activation. The EPR and mechanoreflex were intermittently activated for 1 h via hindlimb static contraction or stretch, respectively. These maneuvers produced significantly greater pressor responses in SHR during the first 25 min of stimulation. Within the NTS, nNOS expression was lower from −14.9 to −13.4 bregma in SHR compared with WKY. For example, at −14.5 bregma the number of NTS nNOS-positive cells in SHR (13 ± 1) was significantly less than WKY (23 ± 2). However, the number of FOS-positive cells after muscle contraction in this area was not different (WKY = 82 ± 18; SHR = 75 ± 8). In both groups, FOS-expressing neurons were located within the same areas of the NTS as neurons containing nNOS. These findings demonstrate that nNOS protein expression is lower within NTS areas excited by skeletal muscle reflexes in hypertensive rats. PMID:23564306

  3. Steam Digest: Volume IV

    SciTech Connect

    Not Available

    2004-07-01

    This edition of the Steam Digest is a compendium of 2003 articles on the technical and financial benefits of steam efficiency, presented by the stakeholders of the U.S. Department of Energy's BestPractices Steam effort.

  4. Steam Digest Volume IV

    SciTech Connect

    2004-07-01

    This edition of the Steam Digest is a compendium of 2003 articles on the technical and financial benefits of steam efficiency, presented by the stakeholders of the U.S. Department of Energy's BestPractices Steam effort.

  5. Steam Digest 2001

    SciTech Connect

    Not Available

    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.

  6. Potential of casein kinase I in digestive cancer screening

    PubMed Central

    Modak, Cristina; Chai, Jianyuan

    2009-01-01

    Casein kinase I is a group of ubiquitous Serine/Threonine kinases that have been implicated in both normal cellular functions and several pathological conditions including Alzheimer’s disease and cancer. Recent findings in colon and pancreatic cancer have brought tremendous attention to these molecules as potential therapeutic targets in treatment of digestive cancers. In this review, we summarize up to date what is known about this family of kinases and their involvement in carcinogenesis and other pathological conditions. Our emphasis is on their implications in digestive cancers and their potential for cancer screening and therapy. PMID:21160770

  7. Digestive-tract sarcoidosis

    PubMed Central

    Ghrenassia, Etienne; Mekinian, Arsene; Chapelon-Albric, Catherine; Levy, Pierre; Cosnes, Jacques; Sève, Pascal; Lefèvre, Guillaume; Dhôte, Robin; Launay, David; Prendki, Virginie; Morell-Dubois, Sandrine; Sadoun, Danielle; Mehdaoui, Anas; Soussan, Michael; Bourrier, Anne; Ricard, Laure; Benamouzig, Robert; Valeyre, Dominique; Fain, Olivier

    2016-01-01

    Abstract Digestive tract sarcoidosis (DTS) is rare and case-series are lacking. In this retrospective case–control study, we aimed to compare the characteristics, outcome, and treatment of patients with DTS, nondigestive tract sarcoidosis (NDTS), and Crohn disease. We included cases of confirmed sarcoidosis, symptomatic digestive tract involvement, and noncaseating granuloma in any digestive tract. Each case was compared with 2 controls with sarcoidoisis without digestive tract involvement and 4 with Crohn disease. We compared 25 cases of DTS to 50 controls with NDTS and 100 controls with Crohn disease. The major digestive clinical features were abdominal pain (56%), weight loss (52%), nausea/vomiting (48%), diarrhea (32%), and digestive bleeding (28%). On endoscopy of DTS, macroscopic lesions were observed in the esophagus (9%), stomach (78%), duodenum (9%), colon, (25%) and rectum (19%). As compared with NDTS, DTS was associated with weight loss (odds ratio [OR] 5.8; 95% confidence interval [CI] 1.44–23.3) and the absence of thoracic adenopathy (OR 5.0; 95% CI 1.03–25). As compared with Crohn disease, DTS was associated with Afro-Caribbean origin (OR 27; 95% CI 3.6–204) and the absence of ileum or colon macroscopic lesions (OR 62.5; 95% CI 10.3–500). On the last follow-up, patients with DTS showed no need for surgery (versus 31% for patients with Crohn disease; P = 0.0013), and clinical digestive remission was frequent (76% vs. 35% for patients with Crohn disease; P = 0.0002). The differential diagnosis with Crohn disease could be an issue with DTS. Nevertheless, the 2 diseases often have different clinical presentation and outcome. PMID:27442665

  8. Biogas stripping of ammonia from fresh digestate from a food waste digester.

    PubMed

    Serna-Maza, A; Heaven, S; Banks, C J

    2015-08-01

    The efficiency of ammonia removal from fresh source-segregated domestic food waste digestate using biogas as a stripping agent was studied in batch experiments at 35, 55 and 70°C, at gas flow rates of 0.125 and 0.250Lbiogasmin(-1)L(-1)digestate with and without pH adjustment. Higher temperatures and alkaline conditions were required for effective ammonia removal, and at 35°C with or without pH adjustment or 55°C with unadjusted pH there was little or no removal. Results were compared to those from earlier studies with digestate that had been stored prior to stripping and showed that ammonia removal from fresh digestate was more difficult, with time constants 1.6-5.7 times higher than those previously reported. This has implications for the design of large-scale systems where continuous stripping of fresh digestate is likely to be the normal operating mode. A mass balance approach showed that thermal-alkaline stripping improved hydrolysis.

  9. Assessment and mitigation of the environmental burdens to air from land applied food-based digestate.

    PubMed

    Tiwary, A; Williams, I D; Pant, D C; Kishore, V V N

    2015-08-01

    Anaerobic digestion (AD) of putrescible urban waste for energy recovery has seen rapid growth over recent years. In order to ascertain its systems scale sustainability, however, determination of the environmental fate of the large volume of digestate generated during the process is indispensable. This paper evaluates the environmental burdens to air associated with land applied food-based digestate in terms of primary pollutants (ammonia, nitrogen dioxide) and greenhouse gases (methane and nitrous oxide). The assessments have been made in two stages - first, the emissions from surface application of food-based digestate are quantified for the business as usual (BAU). In the next step, environmental burden minimisation potentials for the following three mitigation measures are estimated - mixed waste digestate (MWD), soil-incorporated digestate (SID), and post-methanated digestate (PMD). Overall, the mitigation scenarios demonstrated considerable NH3, CH4 and N2O burden minimisation potentials, with positive implications for both climate change and urban pollution.

  10. Slowly digestible starch--a review.

    PubMed

    Miao, Ming; Jiang, Bo; Cui, Steve W; Zhang, Tao; Jin, Zhengyu

    2015-01-01

    The link between carbohydrate intake and health is becoming increasingly important for consumers, particularly in the areas of glycemic index (GI) and extended energy-releasing starches. From a physiological point of view, slowly digestible starch (SDS) delivers a slow and sustained release of blood glucose along with the benefits resulting from low glycemic and insulinemic response. SDS has been implicated in several health problems, including diabetes, obesity, and cardiovascular diseases (metabolic syndromes). It may also have commercial potential as a novel functional ingredient in a variety of fields, such as nutrition, medicine, and agriculture. The present review assesses this form of digestion by analyzing methods to prepare and evaluate SDS, and factors affecting its transformation, its health benefits, and its applications.

  11. Your Digestive System (For Kids)

    MedlinePlus

    ... upon what you've eaten. This process, called digestion , allows your body to get the nutrients and ... tasty food, see it, or think about it, digestion begins. Saliva (say: suh-LYE-vuh), or spit , ...

  12. Molecular assessment of heterotrophy and prey digestion in zooxanthellate cnidarians.

    PubMed

    Leal, M C; Nejstgaard, J C; Calado, R; Thompson, M E; Frischer, M E

    2014-08-01

    Zooxanthellate cnidarians are trophically complex, relying on both autotrophy and heterotrophy. Although several aspects of heterotrophy have been studied in these organisms, information linking prey capture with digestion is still missing. We used prey-specific PCR-based tools to assess feeding and prey digestion of two zooxanthellate cnidarians - the tropical sea anemone Aiptasia sp. and the scleractinian coral Oculina arbuscula. Prey DNA disappeared rapidly for the initial 1-3 days, whereas complete digestion of prey DNA required up to 10 days in O. arbuscula and 5 or 6 days in Aiptasia sp. depending on prey species. These digestion times are considerably longer than previously reported from microscopy-based examination of zooxanthellate cnidarians and prey DNA breakdown in other marine invertebrates, but similar to prey DNA breakdown reported from terrestrial invertebrates such as heteroptera and spiders. Deprivation of external prey induced increased digestion rates during the first days after feeding in O. arbuscula, but after 6 days of digestion, there were no differences in the remaining prey levels in fed and unfed corals. This study indicates that prey digestion by symbiotic corals may be slower than previously reported and varies with the type of prey, the cnidarian species and its feeding history. These observations have important implications for bioenergetic and trophodynamic studies on zooxanthellate cnidarians.

  13. Effects of Aging on the Digestive System

    MedlinePlus

    ... here for the Professional Version Home Digestive Disorders Biology of the Digestive System Effects of Aging on ... Version. DOCTORS: Click here for the Professional Version Biology of the Digestive System Overview of the Digestive ...

  14. Your Digestive System and How It Works

    MedlinePlus

    ... liquids a person consumes each day. Why is digestion important? Digestion is important for breaking down food ... www.ods.od.nih.gov. 1 How does digestion work? Digestion works by moving food through the ...

  15. Bibliotherapy. ERIC Digest.

    ERIC Educational Resources Information Center

    Abdullah, Mardziah Hayati

    This digest suggests that bibliotherapy is a potentially powerful method for school teachers and counselors to use on many levels and in every school grade. It begins with a brief review of the history of bibliotherapy; continues with a discussion of some approaches to bibliotherapy (interactive, clinical, and developmental); then addresses the…

  16. Preventing Bullying. ERIC Digest.

    ERIC Educational Resources Information Center

    Lumsden, Linda

    Students who are the target of bullying episodes commonly suffer serious, long-term academic, physical, and emotional consequences. Unfortunately, school personnel often minimize, underestimate, tolerate, or ignore the extent of bullying and the harm it can cause. This digest examines the problem of bullying and some of its effects, and discusses…

  17. Electronic Networks. ERIC Digest.

    ERIC Educational Resources Information Center

    Garnette, Cheryl Petty

    Electronic network systems, their components--terminal, microcomputer, or communications word processor; telephone, and modem (modulator-demodulator)--and their applications are explained for educators in this digest. Emphasis is on the characteristics and capabilities of: (1) electronic mail, which allows the transmission and reception of…

  18. Positive Discipline. ERIC Digest.

    ERIC Educational Resources Information Center

    ERIC Clearinghouse on Elementary and Early Childhood Education, Urbana, IL.

    This ERIC Digest suggests methods and language that can be used in handling difficult, but common, situations involving young children. Discussion focuses on: (1) 12 methods of discipline that promote self-worth; (2) the process of creating a positive climate that promotes self-discipline; (3) harmful and negative disciplinary methods; and (4)…

  19. The anaerobic digestion process

    SciTech Connect

    Rivard, C.J.; Boone, D.R.

    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.

  20. Digestive tract morphology and digestion in the wombats (Marsupialia: Vombatidae).

    PubMed

    Barboza, P S; Hume, I D

    1992-01-01

    Wombats consume grasses and sedges which are often highly fibrous. The morphology of the digestive tract and the sequence of digestion were studied in two species of wombats from contrasting habitats: Vombatus ursinus from mesic habitats and Lasiorhinus latifrons from xeric regions. Studies were performed on wild wombats consuming their natural winter diets, and on captive wombats fed a high-fibre pelleted straw diet. Vombatus had a shorter digestive tract (9.2 vs 12.5 times body length) of greater capacity (wet contents 17.9 vs 13.7% body weight) than Lasiorhinus. The most capacious region of the digestive tract was the proximal colon (62-79% of contents). The proportional length and surface area of the proximal colon were greater in Vombatus, but those of the distal colon were greater in Lasiorhinus. These digestive morphologies may reflect adaptations for greater capacity and longer retention of digesta in Vombatus, but greater absorption and lower faecal water loss in Lasiorhinus. Apparent digestion along the digestive tract was estimated by reference to lignin. The proximal colon was the principal site of fibre and dry matter digestion, whereas nitrogen was mainly digested in the small intestine. Depot fats in captive wombats were highly unsaturated and reflected those in the diet. Therefore, lipids, proteins and soluble carbohydrates in the plant cell contents were digested and absorbed in the stomach and small intestine. Conversely, dietary fibre was probably retained and digested by microbial fermentation along the proximal colon.

  1. Food microstructure and starch digestion.

    PubMed

    Singh, Jaspreet; Kaur, Lovedeep; Singh, Harjinder

    2013-01-01

    Microstructural characteristics of starch-based natural foods such as parenchyma or cotyledon cell shape, cell size and composition, and cell wall composition play a key role in influencing the starch digestibility during gastrointestinal digestion. The stability of cell wall components and the arrangement of starch granules in the cells may affect the free access of amylolytic enzymes during digestion. Commonly used food processing techniques such as thermal processing, extrusion cooking, and post-cooking refrigerated storage alter the physical state of starch (gelatinization, retrogradation, etc.) and its digestibility. Rheological characteristics (viscosity) of food affect the water availability during starch hydrolysis and, consequently, the absorption of digested carbohydrates in the gastrointestinal tract. The nonstarch ingredients and other constituents present in food matrix, such as proteins and lipids interact with starch during processing, which leads to an alteration in the overall starch digestibility and physicochemical characteristics of digesta. Starch digestibility can be controlled by critically manipulating the food microstructure, processing techniques, and food composition.

  2. Comparative Digestive Physiology

    PubMed Central

    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

  3. Economic viability of anaerobic digestion

    SciTech Connect

    Wellinger, A.

    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.

  4. Gas in the Digestive Tract

    MedlinePlus

    ... History Research Resources Research at NIDDK Meetings & Events Technology Advancement & Transfer Health Information Diabetes Digestive Diseases Kidney Disease Weight Management Liver Disease Urologic Diseases Endocrine Diseases Diet & Nutrition ...

  5. The digestive system: part 1.

    PubMed

    Johnstone, Carolyn; Hendry, Charles; Farley, Alistair; McLafferty, Ella

    This article, which forms part of the life sciences series and is the first of two articles on the digestive system, explores the structure and function of the digestive system. It is important that nurses understand how the digestive system works and its role in maintaining health. The article describes the gross structure of the gastrointestinal tract along with relevant physiology. It also outlines several disorders of the gastrointestinal tract and their treatment and nursing management. The second article will explain the liver, pancreas and gall bladder and their digestive functions, and provides a brief overview of the disorders of chronic liver disease, pancreatitis and gallstones.

  6. Lasers in digestive endoscopy

    NASA Astrophysics Data System (ADS)

    Brunetaud, Jean Marc; Maunoury, Vincent; Cochelard, Dominique

    1997-01-01

    Lasers were introduced in digestive endoscopy to stop active gastroduodenal hemorrhages. Their use spread progressively to the treatment of chronic hemorrhages from vascular malformations and sessile tumors. Laser face competition from other endoscopic techniques such as electrocoagulation, injection techniques, dilation, stents, and brachytherapy. Many series have reported the efficacy of lasers in digestive endoscopy used for their thermal or photochemical effects. However, they were gradually abandoned for the treatment of hemorrhages because of competition from nonlaser techniques. Lasers are still used for ablation of sessile tumors, but their true impact is difficult to evaluate. Modern methods of technology assessment did not allow gastroenterologists to clearly define the place of lasers among surgery, radio-chemotherapy, and other endoscopic techniques, and data on the daily use of lasers are not available. Therefore, the conclusion can only be subjective. The best current application of thermal lasers appears to be in the treatment of rectosigmoid villous adenomas in elderly patients. Small superficial rectal cancers may also become a good subject due to the impact of endoscopic ultrasonography. Early lesions with multifocal or diffuse disease such as early esophageal cancers could be the most promising subject of application for photodynamic therapy in the future.

  7. [Involvement of cross interaction between central cholinergic and histaminergic systems in the nucleus tractus solitarius in regulating carotid sinus baroreceptor reflex].

    PubMed

    Hu, Li-Xun; Zhang, Guo-Xing; Zhang, Yu-Ying; Zhao, Hong-Fen; Yu, Kang-Ying; Wang, Guo-Qing

    2013-12-25

    The carotid sinus baroreceptor reflex (CSR) is an important approach for regulating arterial blood pressure homeostasis instantaneously and physiologically. Activation of the central histaminergic or cholinergic systems results in CSR functional inhibitory resetting. However, it is unclear whether two systems at the nucleus tractus solitarius (NTS) level display cross interaction to regulate the CSR or not. In the present study, the left or right carotid sinus region was isolated from the systemic circulation in Sprague-Dawley rats (sinus nerve was reserved) anesthetized with pentobarbital sodium. Respective intubation was conducted into one side isolated carotid sinus and into the femoral artery for recording the intracarotid sinus pressure (ISP) and mean arterial pressure (MAP) simultaneously with pressure transducers connection in vivo. ISP was set at the level of 0 mmHg to eliminate the effect of initial internal pressure of the carotid sinus on the CSR function. To trigger CSR, the ISP was quickly elevated from 0 mmHg to 280 mmHg in a stepwise manner (40 mmHg) which was added at every step for over 4 s, and then ISP returned to 0 mmHg in similar steps. The original data of ISP and corresponding MAP were fitted to a modified logistic equation with five parameters to obtain the ISP-MAP, ISP-Gain relationship curves and the CSR characteristic parameters, which were statistically compared and analyzed separately. Under the precondition of no influence on the basic levels of the artery blood pressure, the effects and potential regulatory mechanism of preceding microinjection with different cholinoceptor antagonists, the selective cholinergic M1 receptor antagonist, i.e., pirenzepine (PRZ), the M2 receptor antagonist, i.e., methoctramine (MTR) or the N1 receptor antagonist, i.e., hexamethonium (HEX) into the NTS on the changes in function of CSR induced by intracerebroventricular injection (i.c.v.) of histamine (HA) in rats were observed. Meanwhile, the actions and

  8. Digest of Education Statistics, 1998.

    ERIC Educational Resources Information Center

    Snyder, Thomas D.; Hoffman, Charlene M.; Geddes, Claire M.

    This 1998 edition of the "Digest of Education Statistics" is the 34th in a series of publications initiated in 1962. Its primary purpose is to provide a compilation of statistical information covering the broad field of American education from kindergarten through graduate school. The digest includes data from many government and private…

  9. Children and Grief. ERIC Digest.

    ERIC Educational Resources Information Center

    McEntire, Nancy

    Noting that the death of a loved one brings grief to children as well as adults, this Digest draws on research to examine how children respond to death and the role of parents and teachers in helping children cope with loss. The Digest delineates children's "tasks" during mourning that are essential to their adjustment to loss, such as…

  10. Evaluation of thermophilic anaerobic digestion

    SciTech Connect

    Shamskhorzani, R.

    1989-01-01

    The objectives of this study were to examine the effect of temperature on the digestion of a synthetic substrate, alone and with waste activated sludge (WAS), and to determine the effect of nickel, cobalt and molybdenum on thermophilic digestion. Two different types of reactors, batch fed and continuous flow, were operated in four separate phases for over two years. The data indicated that thermophilic digestion could be established from digesting mesophilic domestic sewage sludge by setting the temperature at 50C. An additional acclimation period of about 15 days was required for stimulation of thermophilic bacteria at 60C. Thermophilic digestion at temperatures up to 75C could easily be established in a few days, provided that the digester was well adapted at 60C. The rate of metabolism increased with temperature, reaching an optimum between 60C and 65C. It was possible to shift from 50C to 37C and back to thermophilic temperatures with a minimum of difficulties. Temperature fluctuation of less than 5C did not cause any upset in the performance of the thermophilic digesters operating at 50C to 65C. Addition of Ni, Co and Mo at 1 mg/L appeared to be satisfactory with the suspended solids maintained in the system at long SRT periods. The best substrate removal at 50C was 99.6% reduction at 10 g/L/d COD and 99.6% reduction at 14 g/L/d COD at 55C. The limits for COD loading under a once daily batch fed operations were 24 g/d at 50C and 33 g/d at 55C. The continuous flow fixed-film digester was able to digest WAS with liquid detention times as short as 8 hours. Thirty percent digestion of the volatile solids in WAS was obtained at a 3-day LDT and 16% at an 8-hr LDT.

  11. Application of mechanical shear in an internal-recycle for the enhancement of mesophilic anaerobic digestion.

    PubMed

    Muller, Christopher D; Abu-Orf, Mohammad; Novak, John T

    2007-03-01

    A combination of bench- and full-scale studies were conducted to determine the effectiveness of high-intensity mechanical shear in an internal recycle loop to enhance mesophilic anaerobic digestion and the implications of this process for routine operations of a digestion system. During short-term batch digestion (56 hours), a 46% increase in biogas production was observed. However, it was found that the degree of digestion enhancement was sludge-specific, with increases in volatile solids destruction ranging from 16.6 to 110%. A full-scale demonstration showed increased total and volatile solids destruction of 22 and 21% for the primary digester and 17.2 and 11% for the secondary digester, respectively. The data also suggest that increased protein degradation is one of the major mechanisms associated with the observed increases in volatile solids destruction. The full-scale demonstration also determined that shear enhanced digestion can be operated without process upset, based on volatile fatty acid profile and headspace biogas composition (methane and carbon dioxide). Dewatering properties, as measured by polymer demand, deteriorated in the primary digester, but there was improvement in the secondary digester. High-intensity shear does not appear to enhance pathogen reduction based on total and fecal coliform bacterial enumeration.

  12. Assessing the agricultural reuse of the digestate from microalgae anaerobic digestion and co-digestion with sewage sludge.

    PubMed

    Solé-Bundó, Maria; Cucina, Mirko; Folch, Montserrat; Tàpias, Josefina; Gigliotti, Giovanni; Garfí, Marianna; Ferrer, Ivet

    2017-05-15

    Microalgae anaerobic digestion produces biogas along with a digestate that may be reused in agriculture. However, the properties of this digestate for agricultural reuse have yet to be determined. The aim of this study was to characterise digestates from different microalgae anaerobic digestion processes (i.e. digestion of untreated microalgae, thermally pretreated microalgae and thermally pretreated microalgae in co-digestion with primary sludge). The main parameters evaluated were organic matter, macronutrients and heavy metals content, hygenisation, potential phytotoxicity and organic matter stabilisation. According to the results, all microalgae digestates presented suitable organic matter and macronutrients, especially organic and ammonium nitrogen, for agricultural soils amendment. However, the thermally pretreated microalgae digestate was the least stabilised digestate in comparison with untreated microalgae and co-digestion digestates. In vivo bioassays demonstrated that the digestates did not show residual phytotoxicity when properly diluted, being the co-digestion digestate the one which presented less phytotoxicity. Heavy metals contents resulted far below the threshold established by the European legislation on sludge spreading. Moreover, low presence of E. coli was observed in all digestates. Therefore, agricultural reuse of thermally pretreated microalgae and primary sludge co-digestate through irrigation emerges a suitable strategy to recycle nutrients from wastewater.

  13. Release of protein, lipid, and vitamin E from almond seeds during digestion.

    PubMed

    Mandalari, Giuseppina; Faulks, Richard M; Rich, Gillian T; Lo Turco, Vincenzo; Picout, David R; Lo Curto, Rosario B; Bisignano, Giuseppe; Dugo, Paola; Dugo, Giacomo; Waldron, Keith W; Ellis, Peter R; Wickham, Martin S J

    2008-05-14

    The evaluation of the bioaccessibility of almond nutrients is incomplete. However, it may have implications for the prevention and management of obesity and cardiovascular disease. This study quantified the release of lipid, protein, and vitamin E from almonds during digestion and determined the role played by cell walls in the bioaccessibility of intracellular nutrients. Natural almonds (NA), blanched almonds (BA), finely ground almonds (FG), and defatted finely ground almonds (DG) were digested in vitro under simulated gastric and gastric followed by duodenal conditions. FG were the most digestible with 39, 45, and 44% of lipid, vitamin E, and protein released after duodenal digestion, respectively. Consistent with longer residence time in the gut, preliminary in vivo studies showed higher percentages of nutrient release, and microscopic examination of digested almond tissue demonstrated cell wall swelling. Bioaccessibility is improved by increased residence time in the gut and is regulated by almond cell walls.

  14. Assessing amendment and fertilizing properties of digestates from anaerobic digestion through a comparative study with digested sludge and compost.

    PubMed

    Tambone, Fulvia; Scaglia, Barbara; D'Imporzano, Giuliana; Schievano, Andrea; Orzi, Valentina; Salati, Silvia; Adani, Fabrizio

    2010-10-01

    Digestate, with biogas represents the final products of anaerobic digestion (AD). The methane-rich biogas is used to produce electricity and heat, whereas the digestate could be valorized in agriculture. Contrarily to well-recognized biomasses such as digested sludge and compost, the properties of the digestate are not well known and its agricultural use remains unexplored. In this work, a first attempt to study the agronomic properties of digestates was performed by comparing the chemical, spectroscopic, and biological characteristics of digestates with those of compost and digested sludge, used as reference organic matrices. A total of 23 organic matrices were studied, which include eight ingestates and relative digestates, three composts, and four digested sludges. The analytical data obtained was analyzed using principal component analysis to better show in detail similarities or differences between the organic matrices studied. The results showed that digestates differed from ingestates and also from compost, although the starting organic mix influenced the digestate final characteristics. With respect to amendment properties, it seems that biological parameters, more than chemical characteristics, were more important in describing these features. In this way, amendment properties could be ranked as follows: compost≅digestate>digested sludge≫ingestate. As to fertilizer properties, AD allowed getting a final product (digestate) with very good fertilizing properties because of the high nutrient content (N, P, K) in available form. In this way, the digestate appears to be a very good candidate to replace inorganic fertilizers, also contributing, to the short-term soil organic matter turnover.

  15. Implementing Livestock Anaerobic Digestion Projects

    EPA Pesticide Factsheets

    Page provides information to help make an informed decision about installing an anaerobic digester. Is it a good match for a farm’s organic waste, project financing, development guidelines and permit requirements?

  16. Smoking and Your Digestive System

    MedlinePlus

    ... help digest food. However, these substances may also harm the lining of these organs. Smoking has not ... increase the production of other substances that may harm the lining, such as pepsin, an enzyme made ...

  17. Personal Relationships and Digestive Disorders

    MedlinePlus

    ... Diarrhea Relaxation to Treat Digestive Disorders Medications SAFER Medicine Managing Medications Avoiding Drug Adverse Effects Medications that can Affect Colonic Function Gut Microbiota and Brain-Gut Interactions in Functional GI Disorders Tips & Daily Living Personal Relationships Holiday ...

  18. Nuclear Regulatory Commission information digest

    SciTech Connect

    None,

    1990-03-01

    The Nuclear Regulatory Commission information digest provides summary information regarding the US Nuclear Regulatory Commission, its regulatory responsibilities, and areas licensed by the commission. This is an annual publication for the general use of the NRC Staff and is available to the public. The digest is divided into two parts: the first presents an overview of the US Nuclear Regulatory Commission and the second provides data on NRC commercial nuclear reactor licensees and commercial nuclear power reactors worldwide.

  19. Regulation of serine (Ser)-31 and Ser40 tyrosine hydroxylase phosphorylation during morphine withdrawal in the hypothalamic paraventricular nucleus and nucleus tractus solitarius-A2 cell group: role of ERK1/2.

    PubMed

    Núñez, Cristina; Laorden, M Luisa; Milanés, M Victoria

    2007-12-01

    Our previous studies have shown that naloxone-induced morphine withdrawal increases the hypothalamic-pituitary-adrenocortical (HPA) axis activity, which is dependent on a hyperactivity of noradrenergic pathways [nucleus tractus solitarius (NTS) A(2)] innervating the hypothalamic paraventricular nucleus (PVN). Short-term regulation of catecholamine biosynthesis occurs through phosphorylation of tyrosine hydroxylase (TH), which enhances enzymatic activity. In the present study, the effect of morphine withdrawal on site-specific TH phosphorylation in the PVN and NTS-A(2) was determined by quantitative blot immunolabeling and immunohistochemistry using phosphorylation state-specific antibodies. We show that naloxone-induced morphine withdrawal phosphorylates TH at Serine (Ser)-31 but not Ser40 in PVN and NTS-A(2), which is associated with both an increase in total TH immunoreactivity in NTS-A(2) and an enhanced TH activity in the PVN. In addition, we demonstrated that TH neurons phosphorylated at Ser31 coexpress c-Fos in NTS-A(2). We then tested whether pharmacological inhibition of ERK activation by ERK kinase contributes to morphine withdrawal-induced phosphorylation of TH at Ser31. We show that the ability of morphine withdrawal to stimulate phosphorylation at this seryl residue is reduced by SL327, an inhibitor of ERK(1/2) activation. These results suggest that morphine withdrawal increases noradrenaline turnover in the PVN, at least in part, via ERK(1/2)-dependent phosphorylation of TH at Ser31.

  20. Pressurized Pepsin Digestion in Proteomics

    PubMed Central

    López-Ferrer, Daniel; Petritis, Konstantinos; Robinson, Errol W.; Hixson, Kim K.; Tian, Zhixin; Lee, Jung Hwa; Lee, Sang-Won; Tolić, Nikola; Weitz, Karl K.; Belov, Mikhail E.; Smith, Richard D.; Paša-Tolić, Ljiljana

    2011-01-01

    Integrated top-down bottom-up proteomics combined with on-line digestion has great potential to improve the characterization of protein isoforms in biological systems and is amendable to high throughput proteomics experiments. Bottom-up proteomics ultimately provides the peptide sequences derived from the tandem MS analyses of peptides after the proteome has been digested. Top-down proteomics conversely entails the MS analyses of intact proteins for more effective characterization of genetic variations and/or post-translational modifications. Herein, we describe recent efforts toward efficient integration of bottom-up and top-down LC-MS-based proteomics strategies. Since most proteomics separations utilize acidic conditions, we exploited the compatibility of pepsin (where the optimal digestion conditions are at low pH) for integration into bottom-up and top-down proteomics work flows. Pressure-enhanced pepsin digestions were successfully performed and characterized with several standard proteins in either an off-line mode using a Barocycler or an on-line mode using a modified high pressure LC system referred to as a fast on-line digestion system (FOLDS). FOLDS was tested using pepsin and a whole microbial proteome, and the results were compared against traditional trypsin digestions on the same platform. Additionally, FOLDS was integrated with a RePlay configuration to demonstrate an ultrarapid integrated bottom-up top-down proteomics strategy using a standard mixture of proteins and a monkey pox virus proteome. PMID:20627868

  1. Structure of a cellulose degrading bacterial community during anaerobic digestion.

    PubMed

    O'Sullivan, Cathryn A; Burrell, Paul C; Clarke, William P; Blackall, Linda L

    2005-12-30

    It is widely accepted that cellulose is the rate-limiting substrate in the anaerobic digestion of organic solid wastes and that cellulose solubilisation is largely mediated by surface attached bacteria. However, little is known about the identity or the ecophysiology of cellulolytic microorganisms from landfills and anaerobic digesters. The aim of this study was to investigate an enriched cellulolytic microbial community from an anaerobic batch reactor. Chemical oxygen demand balancing was used to calculate the cellulose solubilisation rate and the degree of cellulose solubilisation. Fluorescence in situ hybridisation (FISH) was used to assess the relative abundance and physical location of three groups of bacteria belonging to the Clostridium lineage of the Firmicutes that have been implicated as the dominant cellulose degraders in this system. Quantitation of the relative abundance using FISH showed that there were changes in the microbial community structure throughout the digestion. However, comparison of these results to the process data reveals that these changes had no impact on the cellulose solubilisation in the reactor. The rate of cellulose solubilisation was approximately stable for much of the digestion despite changes in the cellulolytic population. The solubilisation rate appears to be most strongly affected by the rate of surface area colonisation and the biofilm architecture with the accepted model of first order kinetics due to surface area limitation applying only when the cellulose particles are fully covered with a thin layer of cells.

  2. Nutrition, Health, and Regulatory Aspects of Digestible Maltodextrins

    PubMed Central

    Hofman, Denise L.; van Buul, Vincent J.; Brouns, Fred J. P. H.

    2016-01-01

    Digestible maltodextrins are low-sweet saccharide polymers consisting of D-glucose units linked primarily linearly with alpha-1,4 bonds, but can also have a branched structure through alpha-1,6 bonds. Often, maltodextrins are classified by the amount of reducing sugars present relative to the total carbohydrate content; between 3 and 20 percent in the case of digestible maltodextrins. These relatively small polymers are used as food ingredients derived by hydrolysis from crops naturally rich in starch. Through advances in production technology, the application possibilities in food products have improved during the last 20 years. However, since glucose from digested maltodextrins is rapidly absorbed in the small intestine, the increased use has raised questions about potential effects on metabolism and health. Therefore, up-to-date knowledge concerning production, digestion, absorption, and metabolism of maltodextrins, including potential effects on health, were reviewed. Exchanging unprocessed starch with maltodextrins may lead to an increased glycemic load and therefore post meal glycaemia, which are viewed as less desirable for health. Apart from beneficial food technological properties, its use should accordingly also be viewed in light of this. Finally, this review reflects on regulatory aspects, which differ significantly in Europe and the United States, and, therefore, have implications for communication and marketing. PMID:25674937

  3. Nutrition, Health, and Regulatory Aspects of Digestible Maltodextrins.

    PubMed

    Hofman, Denise L; van Buul, Vincent J; Brouns, Fred J P H

    2016-09-09

    Digestible maltodextrins are low-sweet saccharide polymers consisting of D-glucose units linked primarily linearly with alpha-1,4 bonds, but can also have a branched structure through alpha-1,6 bonds. Often, maltodextrins are classified by the amount of reducing sugars present relative to the total carbohydrate content; between 3 and 20 percent in the case of digestible maltodextrins. These relatively small polymers are used as food ingredients derived by hydrolysis from crops naturally rich in starch. Through advances in production technology, the application possibilities in food products have improved during the last 20 years. However, since glucose from digested maltodextrins is rapidly absorbed in the small intestine, the increased use has raised questions about potential effects on metabolism and health. Therefore, up-to-date knowledge concerning production, digestion, absorption, and metabolism of maltodextrins, including potential effects on health, were reviewed. Exchanging unprocessed starch with maltodextrins may lead to an increased glycemic load and therefore post meal glycaemia, which are viewed as less desirable for health. Apart from beneficial food technological properties, its use should accordingly also be viewed in light of this. Finally, this review reflects on regulatory aspects, which differ significantly in Europe and the United States, and, therefore, have implications for communication and marketing.

  4. Hemicellulose conversion by anaerobic digestion

    SciTech Connect

    Ghosh, S.; Henry, M.P.; Christopher, R.W.

    1982-01-01

    The digestibility of an aquatic biomass (water hyacinth), a land-based biomass (Coastal Bermuda grass), and a biomass-waste blend (a mixture of hyacinth, grass, MSW, and sludge) under various digestion conditions was studied. Anaerobic digestion of hemicellulose consists of the steps of enzymatic hydrolysis of hemicellulose to glucans, mannans, galactans, xylans, and arabans, and then to simple hexose and pentose sugars; production of C/sub 2/ and higher fatty acids from the simple sugars; conversion of higher fatty acids to acetate; and finally, production of methane and CO/sub 2/ from acetate, and CO/sub 2/ and hydrogen. The conversion of hemicellulose was higher under mesophilic conditions than those of cellulose or protein for all biomass test feeds, probably because the hemicellulose structure was more vulnerable to enzymatic attack than that of the lignocellulosic component. Cellulose conversion efficiencies at the mesophilic and thermophilic temperatures were about the same. However, hemicellulose was converted at a much lower efficiency than cellulose during thermophilic digestion - a situation that was the reverse of that observed at the mesophilic temperature. Cellulose was utilized in preference to hemicellulose during mesophilic digestion of nitrogen-supplemented Bermuda grass. It was speculated that Bermuda grass cellulose was converted at a higher efficiency than hemicellulose in the presence of external nitrogen because the metabolism of the breakdown product (glucose) of cellulose requires the least investment of enzymes and energy.

  5. DIGESTER GAS - FUEL CELL - PROJECT

    SciTech Connect

    Dr.-Eng. Dirk Adolph; Dipl.-Eng. Thomas Saure

    2002-03-01

    GEW has been operating the first fuel cell in Europe producing heat and electricity from digester gas in an environmentally friendly way. The first 9,000 hours in operation were successfully concluded in August 2001. The fuel cell powered by digester gas was one of the 25 registered ''Worldwide projects'' which NRW presented at the EXPO 2000. In addition to this, it is a key project of the NRW State Initiative on Future Energies. All of the activities planned for the first year of operation were successfully completed: installing and putting the plant into operation, the transition to permanent operation as well as extended monitoring till May 2001.

  6. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; comparison of a nitric acid in-bottle digestion procedure to other whole-water digestion procedures

    USGS Publications Warehouse

    Garbarino, John R.; Hoffman, Gerald L.

    1999-01-01

    A hydrochloric acid in-bottle digestion procedure is used to partially digest wholewater samples prior to determining recoverable elements by various analytical methods. The use of hydrochloric acid is problematic for some methods of analysis because of spectral interference. The inbottle digestion procedure has been modified to eliminate such interference by using nitric acid instead of hydrochloric acid in the digestion. Implications of this modification are evaluated by comparing results for a series of synthetic whole-water samples. Results are also compared with those obtained by using U.S. Environmental Protection Agency (1994) (USEPA) Method 200.2 total-recoverable digestion procedure. Percentage yields that use the nitric acid inbottle digestion procedure are within 10 percent of the hydrochloric acid in-bottle yields for 25 of the 26 elements determined in two of the three synthetic whole-water samples tested. Differences in percentage yields for the third synthetic whole-water sample were greater than 10 percent for 16 of the 26 elements determined. The USEPA method was the most rigorous for solubilizing elements from particulate matter in all three synthetic whole-water samples. Nevertheless, the variability in the percentage yield by using the USEPA digestion procedure was generally greater than the in-bottle digestion procedure, presumably because of the difficulty in controlling the digestion conditions accurately.

  7. Slow digestion property of native cereal starches.

    PubMed

    Zhang, Genyi; Ao, Zihua; Hamaker, Bruce R

    2006-11-01

    The slow digestion property of native cereal starches, represented by normal maize starch, was investigated. The in vitro Englyst test showed that 53.0% of the maize starch is slowly digestible starch (SDS), and scanning electron microscopy (SEM) revealed that SDS starts from an increase of pore size until almost complete fragmentation of starch granules. However, similar amounts of SDS ( approximately 50%) were shown for partially digested fragmented starch residuals, which would normally be considered resistant to digestion based on the Englyst assay. Molecularly, both amylopectin (AP) and amylose (AM) contributed to the amount of SDS as evidenced by a similar ratio of AP to AM at different digestion times. Consistently, similar degrees of crystallinity, comparable gelatinization behavior, and similar debranched profiles of starch residuals following different digestion times indicated that the crystalline and amorphous regions of starch granules were evenly digested through a mechanism of side-by-side digestion of concentric layers of semicrystalline shells of native starch granules.

  8. Dietary Sodium Suppresses Digestive Efficiency via the Renin-Angiotensin System.

    PubMed

    Weidemann, Benjamin J; Voong, Susan; Morales-Santiago, Fabiola I; Kahn, Michael Z; Ni, Jonathan; Littlejohn, Nicole K; Claflin, Kristin E; Burnett, Colin M L; Pearson, Nicole A; Lutter, Michael L; Grobe, Justin L

    2015-06-11

    Dietary fats and sodium are both palatable and are hypothesized to synergistically contribute to ingestive behavior and thereby obesity. Contrary to this hypothesis, C57BL/6J mice fed a 45% high fat diet exhibited weight gain that was inhibited by increased dietary sodium content. This suppressive effect of dietary sodium upon weight gain was mediated specifically through a reduction in digestive efficiency, with no effects on food intake behavior, physical activity, or resting metabolism. Replacement of circulating angiotensin II levels reversed the effects of high dietary sodium to suppress digestive efficiency. While the AT1 receptor antagonist losartan had no effect in mice fed low sodium, the AT2 receptor antagonist PD-123,319 suppressed digestive efficiency. Correspondingly, genetic deletion of the AT2 receptor in FVB/NCrl mice resulted in suppressed digestive efficiency even on a standard chow diet. Together these data underscore the importance of digestive efficiency in the pathogenesis of obesity, and implicate dietary sodium, the renin-angiotensin system, and the AT2 receptor in the control of digestive efficiency regardless of mouse strain or macronutrient composition of the diet. These findings highlight the need for greater understanding of nutrient absorption control physiology, and prompt more uniform assessment of digestive efficiency in animal studies of energy balance.

  9. An Aerobic Digestion of Lime Sludge.

    DTIC Science & Technology

    1982-07-01

    defined for process control. LITERATURE REVIEW GENERAL CONDITIONS The process of anaerobic digestion may be considered to occur in three stages . The... anaerobic digestion process can result in significantly higher digester volume require- ments. The characteristics of lime sludge degradatioA were...considerations: 1. The stabilized sludge must be of acceptable quality for disposal for the anaerobic digestion process to be feasible. 2. Since

  10. Digestion of carbohydrates in the pig.

    PubMed

    Drochner, W

    1993-01-01

    A review of carbohydrate digestion in the pig is given. The cascade of digestion in the mouth, stomach, small and large intestine is described. Principles of enzymatic and fermentative digestion according to new results with fistulated animals are discussed. The efficacy and quality of fermentation in the large intestine depending on level and quality of carbohydrates in the diet are demonstrated. Some aspects of energetical efficacy of hindgut digestion are discussed. Dietetic effects of carbohydrates are described.

  11. Digestion and Absorption of Carbohydrates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Carbohydrates are the major dietary sources of energy for humans. While most dietary carbohydrates are derived from multiple botanical sources, lactose and trehalose are the only animal-derived carbohydrates. Digestion of starch, the carbohydrate most abundantly consumed by humans, depends on the c...

  12. Infant Child Care. ERIC Digest.

    ERIC Educational Resources Information Center

    Howes, Carollee

    This ERIC Digest briefly reviews studies of maternal employment, child care settings, and links between children's development and family and child care influences. Studies of maternal employment suggest that infants' positive relationships with caregivers may compensate for insecure attachments with mothers. If future research supports this…

  13. Schools within Schools. ERIC Digest.

    ERIC Educational Resources Information Center

    McAndrews, Tobin; Anderson, Wendell

    Schools within schools are large public schools that have been divided into smaller autonomous subunits to create a sense of community and cohesiveness among students and staff. This digest discusses the benefits, drawbacks, varieties, and sources of funding for schools within schools. Designers of these schools seek the advantages of both large…

  14. Single Sex Education. WEEA Digest.

    ERIC Educational Resources Information Center

    Pollard, Diane S.

    Title IX of the Educational Amendments of 1972 prohibits discrimination on the basis of sex in educational institutions that receive federal financial assistance. This digest focuses on the theme of single-sex education. Articles featured in this issue include: (1) "Single-Sex Education" (Diane S. Pollard); (2) "A Legal Framework for Single-Sex…

  15. Library Latchkey Children. ERIC Digest.

    ERIC Educational Resources Information Center

    Dowd, Frances Smardo

    This digest discusses ways in which public libraries deal with latchkey children who spend their after-school hours at public libraries while their parents are at work. Research conducted in 1990 of 110 public libraries revealed that almost all libraries encountered unattended children after school hours, and that most libraries surveyed were not…

  16. The Shy Child. ERIC Digest.

    ERIC Educational Resources Information Center

    Hyson, Marion C.; Van Trieste, Karen

    This ERIC digest: (1) describes types and manifestations of shyness among children; (2) briefly reviews research on genetic, temperamental, and environmental influences on shyness; (3) distinguishes between normal and problematic shyness; and (4) suggests ways for parents and teachers to help the shy child by accepting the whole child, building…

  17. Tropical Rainforest Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Rillero, Peter

    This digest provides four guideposts for tropical rainforest education: (1) structure; (2) location and climate; (3) importance; and (4) conservation of resources. Research is cited and background information provided about the layers of life and the adaptations of life within the tropical rain forest. Aspects of life within and near rain forests…

  18. Commercialism in Schools. ERIC Digest.

    ERIC Educational Resources Information Center

    Larson, Kirstin

    Businesses are increasingly making inroads into the classroom, particularly in underfunded schools. The dramatic rise in commercial activities in schools has sparked intense public debate, triggering a U.S. General Accounting Office (GAO) report and various regulatory attempts at district, state, and federal levels. This digest offers an overview…

  19. Teaching about Ecosystems. ERIC Digest.

    ERIC Educational Resources Information Center

    Haury, David L.

    Ecosystems are available to educators as interactive units and as such the National Science Education Standards (NSES) and the Excellence in Environmental Education: Guidelines for Learning (EEE) put considerable emphasis on ecosystems. This ERIC Digest describes the NSES and EEE guidelines for grades 5-8 and 9-12 to provide a basic ecosystem…

  20. Incentives for Accountability. ERIC Digest.

    ERIC Educational Resources Information Center

    Lashway, Larry

    Policymakers and educators are taking a new look at incentives as they work to improve accountability systems. This ERIC Digest examines the role of rewards and sanctions in school reform and identifies key issues in implementing incentive systems. The new accountability is based on five components: carefully designed standards, assessments…

  1. The Only Child. ERIC Digest.

    ERIC Educational Resources Information Center

    Steiner, Karen

    Smaller families in general (including the one-child option) are becoming more popular. This ERIC Digest focuses on changing trends in family size, reasons for choosing to have only one child, differences between only children and those with siblings, and the advantages of being an only child. Changing family patterns, economic concerns, and new…

  2. The Wired Campus. ERIC Digest.

    ERIC Educational Resources Information Center

    Schamber, Linda

    This ERIC Digest examines some of the trends and issues in academic information systems design and describes the policies of several universities that are taking creative advantage of these systems as educational tools. The current emphasis on microcomputers in campus information networks instead of terminals connected to a mainframe computer is…

  3. Interpersonal Process Recall. ERIC Digest.

    ERIC Educational Resources Information Center

    Cashwell, Craig S.

    This digest focuses on Information Process Recall (IPR), a supervision strategy developed to increase counselor awareness of covert thoughts and feelings and to deepen the therapeutic relationship between the counselor and the client. Steps in conducting IPR are given as a guideline for conducting IPR recall sessions using audio or video tapes. To…

  4. Rural School Busing. ERIC Digest.

    ERIC Educational Resources Information Center

    Howley, Aimee; Howley, Craig

    This digest summarizes information suggesting that long bus rides are part of the hidden costs of school and district consolidation. Rural school districts spend more than twice per pupil what urban districts spend on transportation. A review of studies shows that rural school children were more likely than suburban school children to have bus…

  5. Teaching about Oceans. ERIC Digest.

    ERIC Educational Resources Information Center

    Fortner, Rosanne W.

    This ERIC Digest is designed for teachers in grades K-12 to share a rationale for teaching about oceans and briefly introduce the kinds of resources available to assist with such efforts. Topics include: (1) Why teach about oceans?; (2) Where can I get resources for teaching about the ocean?; (3) Who is doing marine education in my area?; (4) What…

  6. Transforming Principal Preparation. ERIC Digest.

    ERIC Educational Resources Information Center

    Lashway, Larry

    In the current climate of accountability, the responsibilities of principals have increased. The new role of principals requires new forms of training, and standards-based reform is generating major changes in principal-preparation programs. This digest examines some of those changes. First, it looks at the effectiveness of principal-preparation…

  7. Pattern Identification Exercise. ERIC Digest.

    ERIC Educational Resources Information Center

    Amundson, Norm

    Career exploration typically involves the investigation of personal factors: interests, aptitudes, values, and personal style. This digest outlines one counseling method, pattern identification exercise (PIE). PIE starts with past experiences and identifies personal patterns which are relevant to career decisions. A premise of PIE is that…

  8. Building Halos by Digesting Satellites

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-05-01

    We think galactic halos are built through the addition of material from the smaller subhalos of satellites digested by their hosts. Though most of the stars in Milky-Way-mass halos were probably formed in situ, many were instead accumulated over time, as orbiting dwarf galaxies were torn apart and their stars flung throughout the host galaxy. A recent set of simulations has examined this brutal formation process.In the authors simulations, a subhalo first falls into the host halo. At this point, it can either survive to present day as a satellite galaxy, or it can be destroyed, its stars scattering throughout the host halo. [Deason et al. 2016]Subhalo FateThere are many open questions about the growth of Milky-Way-mass halos from the accretion of subhalos. Which subhalos are torn apart and accreted, and which ones survive intact? Are more small or large subhalos accreted? Does subhalo accretion affect the host galaxys metallicity? And what can we learn from all of this about the Milky Ways formation history?In a recently published study, a team of scientists from Stanford University and SLAC National Accelerator Laboratory set out to answer these questions using a suite of 45 zoom-in simulations of Milky-Way-mass halos. Led by Alis Deason, the team tracked the accretion history of these 45 test galaxies to determine how their halos were built.Piecing Together HistoryDeason and collaborators reach several new and interesting conclusions based on the outcomes of their simulations.Average accreted stellar mass from destroyed dwarfs for each host halo, as a function of the time of the last major accretion event. More stellar mass is accreted in more recent accretion events. [Deason et al. 2016]Most of the stellar mass accreted by the Milky-Way-mass halos typically comes from only one or two destroyed dwarfs. The accreted dwarfs are usually low-mass if they were accreted early on in the simulation (i.e., in the early universe), and high-mass if they were accreted

  9. Testing low cost anaerobic digestion (AD) systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  10. The National Research and Education Network (NREN): Promise of New Information Environments. ERIC Digest.

    ERIC Educational Resources Information Center

    Bishop, Ann P.

    This digest describes proposed legislation for the implementation of the National Research and Education Network (NREN). Issues and implications for teachers, students, researchers, and librarians are suggested and the emergence of the electronic network as a general communication and research tool is described. Developments in electronic…

  11. Experimental digester facility modifications and digester gas upgrading research

    SciTech Connect

    Srivastava, V.J.; Biljetina, R.; Akin, C.

    1989-01-01

    The Institute of Gas Technology (IGT) has been participating in an experimental program at the Community Waste Research Facility (CWRF) located at the Walt Disney World Resort Complex, Orlando, Florida. Four institutions have formed a team to provide solutions to community waste treatment and disposal programs. Of primary importance to this research effort is the implementation of low-cost, energy-efficient waste treatment and recovery technologies and the net production of energy (methane) from biomass and waste resources. The production of methane is being studied in a novel, high-rate digester. During 1988, we were responsible for modifying the Experimental Test Unit (ETU) to permit dry solids feeding of refuse-derived fuel (RDF) and for conducting bench-scale experiments to evaluate techniques for efficient removal of carbon dioxide produced during anaerobic digestion.

  12. Advanced thermophilic digestion of biomass blends

    SciTech Connect

    Ghosh, S.

    1982-05-01

    The development of an advanced thermophilic biomass-digestion process that could be operated at much higher loading and slurry throughput rates than those of conventional high-rate digestion was reported. The biomass blend (mixture of hyacinth, Bermuda grass, refuse, and sludge) effected superior digester performance than the pure biomass feeds. For the pure feeds, mesophilic (35/sup 0/C) digestion was better than thermophilic (55/sup 0/C) digestion; the reverse was true for the biomass-waste blend substrate. The blend feed had higher biodegradability, and was selected as the substrate for an advanced digestion process. The advanced thermophilic process consisted of alkaline pretreatment of the undiluted blend feed at 55/sup 0/C, recycling of spent alkali to treat the fresh feed, neutralization of the treated feed with digester gas to a high pH (9 to 10), and digestion in a complete-mix digester. Methane yield and gas production rate from the advanced process were significantly higher than those from conventional digestion despite the fact that loading and hydraulic throughput rates for the former process were considerably higher than those of the latter. Reactor volume for the advanced process could be less than 20% and net energy production more than double those for conventional mesophilic high-rate digestion.

  13. Starch digestibility of foods: a nutritional perspective.

    PubMed

    Dreher, M L; Dreher, C J; Berry, J W

    1984-01-01

    Dietary starch varies greatly in digestibility and its effects on the utilization of other nutrients. The variation appears to be due to differences in starch components and their crystallinity. Processing treatments, storage conditions, chemical modification, and genetic breeding influence the digestibility of starch. Cereal starches are generally more digestible than root/tuber and legume starches. Although cooking often significantly improves the digestibility of poor and intermediately digestible starches, some foods such as bananas with starches of these types are consumed uncooked. The efficient digestion of starch is especially important to specific groups of people such as infants under 6 months of age. Ruminants must also be provided with highly digestible starch to assure maximum production efficiency. Poor digestibility of starch may have negative effects on the utilization of protein and minerals but is likely to have positive effects on the availability of certain vitamins. Decreases in the rate of starch digestion may have therapeutic application. Most clinical studies have reported that starch blockers do not elicit a significant decrease in the digestion of starch in humans. Much remains to be learned, clarified, and understood about starch digestion and its effects on diabetes and weight control.

  14. Mechanism of extraordinary DNA digestion by pepsin.

    PubMed

    Zhang, Yanfang; Li, Chunchuan; Liu, Yu; Wang, Xiaoqian; Dong, Ping; Liang, Xingguo

    2016-03-25

    Recently, the protein-specific enzyme pepsin was found be capable of digesting nucleic acids unexpectedly. In this study, the effects of DNA sequence specificity, purine content (AG content), depurination and length on the nucleic acid (NA) digestion by pepsin were investigated. The results showed that pepsin functioned similar as endonuclease, and presented a moderate sequence preference compared with restriction enzymes and non-specific nuclease. The digestion was specific (sequence dependent to some extent), and pepsin preferred to cleave purine-rich sequences. The digestion of favorable sequence was dramatically accelerated when the purine base at the cleavage site was removed (created an apurinic (AP) site). However, the AP site did not help to cleave the sequence that pepsin could not cleave originally. Moreover, the results indicated that pepsin preferred to digest longer DNA (e.g. > 59 bases) than shorter one, and sequence shorter than 30 bases was barely digested. The mechanism of DNA digestion by pepsin was also discussed.

  15. Low-digestible carbohydrates in practice.

    PubMed

    Grabitske, Hollie A; Slavin, Joanne L

    2008-10-01

    Low-digestible carbohydrates are carbohydrates that are incompletely or not absorbed in the small intestine but are at least partly fermented by bacteria in the large intestine. Fiber, resistant starch, and sugar alcohols are types of low-digestible carbohydrates. Given potential health benefits (including a reduced caloric content, reduced or no effect on blood glucose levels, non-cariogenic effect), the prevalence of low-digestible carbohydrates in processed foods is increasing. Low-digestible carbohydrate fermentation in the gut causes gastrointestinal effects, especially at higher intakes. We review the wide range of low-digestible carbohydrates in food products, offer advice on identifying low-digestible carbohydrates in foods and beverages, and make suggestions for intakes of low-digestible carbohydrates.

  16. Lignin analysis using microwave digestion.

    PubMed

    Gassara, Fatma; Ajila, C M; Brar, Satinder K; Tyagi, R D; Verma, M; Valero, J R

    2012-10-01

    Lignin quantification in apple pomace residues was carried out using a microwave oven to replace traditional refluxing during the mild acidolysis step to augment the selectivity of this step towards cleavage of lignin-carbohydrate bonds and to reduce the time needed to quantify lignin. The pressure, temperature and time were optimized by response surface methodology and the results were compared to the Klason lignin methodology. Temperature and pressure had a significant positive effect (p < 0.05) on the determination of lignin. However, the time was also significant (p < 0.05) on lignin quantification. The optimal conditions of digestion were: 30 bar, 170 °C for 15 min. The digestion using microwave (lignin content = 33 % w/w) was more accurate (p < 0.05) than the the traditional refluxing (lignin content = 27 % w/w).

  17. Isotopic Changes During Digestion: Protein

    NASA Astrophysics Data System (ADS)

    Tuross, N.

    2013-12-01

    Nutrient and hydrological inputs traverse a complicated route of pH, enzymatic and cellular processes in digestion in higher animals. The end products of digestion are the starting products for biosynthesis that are often used to interpret past life-ways. Using an artificial gut system, the isotopic changes (dD, d18O, d13C and d15N) of protein are documented. Three separate protein sources are subjected to the conditions, chemical and enzymatic, found in the stomach and upper small intestine with only a small shift in the oxygen isotopic composition of the proteins observed. Middle to lower small intestine parameters produced both greater isotopic effects and significantly lower molecular weight products. The role of the gastric enterocyte and the likely involvement of the internal milieu of this cell in the isotopic composition of amino acids that are transported to the liver are reported.

  18. [Iron deficiency and digestive disorders].

    PubMed

    Cozon, G J N

    2014-11-01

    Iron deficiency anemia still remains problematic worldwide. Iron deficiency without anemia is often undiagnosed. We reviewed, in this study, symptoms and syndromes associated with iron deficiency with or without anemia: fatigue, cognitive functions, restless legs syndrome, hair loss, and chronic heart failure. Iron is absorbed through the digestive tract. Hepcidin and ferroportin are the main proteins of iron regulation. Pathogenic micro-organisms or intestinal dysbiosis are suspected to influence iron absorption.

  19. Anaerobic digestion in rural China

    SciTech Connect

    Henderson, J.P.

    1997-01-01

    The People`s Republic of China has been promoting underground, individual, anaerobic digesters to process rural organic materials. This strategy has resulted in approximately five million household anaerobic digesters installed in China today. Simple reactors provide energy and fertilizer for Chinese farms and villages. Another benefit includes improved household sanitation. Reactor design has evolved over time. In the standard modern design, effluent is removed from the reactor at the top of the water column, meaning that supernatant is collected rather than sludge. Additionally, no mixing of the system occurs when effluent is removed. In some systems, a vertical cylindrical pull-rod port is added to the base of the effluent port. Effluent is removed by moving the pull-rod - simply a wooden shaft with a metal disk on the bottom - up and down in the port. A bucket can be placed directly under the pull-rod port, simplifying effluent removal, while the movement of the wooden shaft provides some mixing in the reactor. The gas primarily is used for cooking and lighting. A digester can provide approximately 60 percent of a family`s energy needs. Effluent from the reactors is an odorless, dark colored slurry, primarily used as an agricultural fertilizer. 3 figs.

  20. Implications of Research on Displaced Workers. ERIC Digest No. 80.

    ERIC Educational Resources Information Center

    Naylor, Michele

    Worker displacement is more closely related to structural features associated with firms than to the characteristics of the individuals who lost their jobs. Despite economic growth, large numbers of displaced workers continue to experience difficulty in making labor market adjustments. Programs to retrain and reemploy displaced workers exist at…

  1. Self-Esteem and Narcissism: Implications for Practice. ERIC Digest.

    ERIC Educational Resources Information Center

    Katz, Lilian G.

    While the development of children's self-esteem is a worthwhile goal in early education, many practices designed to reach this goal may instead be encouraging narcissism. Such practices include those that direct children's attention to their own inner gratifications, or encourage children to believe their specialness is dependent on trivial…

  2. Toxoplasma gondii Ingests and Digests Host Cytosolic Proteins

    PubMed Central

    Dou, Zhicheng; McGovern, Olivia L.; Di Cristina, Manlio

    2014-01-01

    ABSTRACT The protozoan parasite Toxoplasma gondii resides within a nonfusogenic vacuole during intracellular replication. Although the limiting membrane of this vacuole provides a protective barrier to acidification and degradation by lysosomal hydrolases, it also physically segregates the parasite from the host cytosol. Accordingly, it has been suggested that T. gondii acquires material from the host via membrane channels or transporters. The ability of the parasite to internalize macromolecules via endocytosis during intracellular replication has not been tested. Here, we show that Toxoplasma ingests host cytosolic proteins and digests them using cathepsin L and other proteases within its endolysosomal system. Ingestion was reduced in mutant parasites lacking an intravacuolar network of tubular membranes, implicating this apparatus as a possible conduit for trafficking to the parasite. Genetic ablation of proteins involved in the pathway is associated with diminished parasite replication and virulence attenuation. We show that both virulent type I and avirulent type II strain parasites ingest and digest host-derived protein, indicating that the pathway is not restricted to highly virulent strains. The findings provide the first definitive evidence that T. gondii internalizes proteins from the host during intracellular residence and suggest that protein digestion within the endolysosomal system of the parasite contributes to toxoplasmosis. PMID:25028423

  3. Index to USA Aviation Digest, 1991

    DTIC Science & Technology

    1992-11-01

    Aviation Digest; Nov-Dec 1991: p. 42. CIPPS SEE CIVILIAN INTEGRATION INTO THE PERSONNEL PROPONENCY SYSTEM ( CIPPS ) CIVILIAN INTEGRATION INTO THE PERSONNEL...PROPONENCY SYSTEM ( CIPPS ) Civilian integration into the Personnel Proponency System ( CIPPS ). USA Aviation Digest; Jul-Aug 1991: p. 28. CMIF SEE...HASTINGS, ROBERT T. Twenty commandments for platoon leaders. USA Aviation Digest; Mar-Apr 1991: p. 30-31. HAYES, THOMAS M. Delta models at the

  4. The anaerobic digestion of organic solid wastes

    SciTech Connect

    Hartung, H.A.

    1996-09-01

    Anaerobic digestion offers many advantages in the processing of organic solid wastes, using a closed system to convert the waste to combustible gas and a stabilized organic residue.Odors are contained while digestion removes their source and gas is collected for energy recovery as heat or electricity. The stabilized residue is less than the starting waste by the mass of gas produced, and it can be disposed of by land application, land filling, incineration or composting. The stimulation of digesters and the phenomenon of co-digestion are two ways the performance of anaerobic digesters can be enhanced. Data from farm digesters and municipal wastewater treatment plants illustrate the present venue of the process; laboratory studies of the anaerobic digestion of a variety of solid wastes show that the process can be applied to these materials as well. About two thirds of municipal solid waste is shown to be amenable to anaerobic digestion in a substrate from an active municipal sewage plant digester.

  5. Steam Digest 2001: Office of Industrial Technologies

    SciTech Connect

    None, None

    2002-01-01

    Steam Digest 2001 chronicles Best Practices Program's contributions to the industrial trade press for 2001, and presents articles that cover technical, financial and managerial aspects of steam optimization.

  6. Anaerobic Digestion. Student Manual. Biological Treatment Process Control.

    ERIC Educational Resources Information Center

    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…

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

    PubMed

    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 < soybean oil < DAG. In simulated in vitro 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) < soybean oil (t'1/2 = 18.74 min) < DAG (t'1/2 = 29.08 min). The parameters obtained using the 2 models showed MCT was digested faster than soybean oil, and that soybean oil was digested faster than DAG.

  8. Anaerobic digestion of aliphatic polyesters.

    PubMed

    Šmejkalová, Pavla; Kužníková, Veronika; Merna, Jan; Hermanová, Soňa

    2016-01-01

    Anaerobic processes for the treatment of plastic materials waste represent versatile and effective approach in environmental protection and solid waste management. In this work, anaerobic biodegradability of model aliphatic polyesters, poly(L-lactic acid) (PLA), and poly(ɛ-caprolactone) (PCL), in the form of powder and melt-pressed films with varying molar mass, was studied. Biogas production was explored in batch laboratory trials at 55 ± 1°C under a nitrogen atmosphere. The inoculum used was thermophilic digested sludge (total solids concentration of 2.9%) from operating digesters at the Central Waste Water Treatment Plant in Prague, Czech Republic. Methanogenic biodegradation of PCLs typically yielded from 54 to 60% of the theoretical biogas yield. The biodegradability of PLAs achieved from 56 to 84% of the theoretical value. High biogas yield (up to 677 mL/g TS) with high methane content (more than 60%), comparable with conventionally processed materials, confirmed the potential of polyester samples for anaerobic treatment in the case of their exploitation in agriculture or as a packaging material in the food industry.

  9. Impact of dietary fibers [methyl cellulose, chitosan, and pectin] on digestion of lipids under simulated gastrointestinal conditions.

    PubMed

    Espinal-Ruiz, Mauricio; Parada-Alfonso, Fabián; Restrepo-Sánchez, Luz-Patricia; Narváez-Cuenca, Carlos-Eduardo; McClements, David Julian

    2014-12-01

    A simulated in vitro digestion model was used to elucidate the impact of dietary fibers on the digestion rate of emulsified lipids. The influence of polysaccharide type (chitosan (cationic), methyl cellulose (non-ionic), and pectin (anionic)) and initial concentration (0.4 to 3.6% (w/w)) was examined. 2% (w/w) corn oil-in-water emulsions stabilized by 0.2% (w/w) Tween-80 were prepared, mixed with polysaccharide, and then subjected to an in vitro digestion model (37 °C): initial (pH 7.0); oral (pH 6.8; 10 min); gastric (pH 2.5; 120 min); and, intestinal (pH 7.0; 120 min) phases. The impact of polysaccharides on lipid digestion, ζ-potential, particle size, viscosity, and stability was determined. The rate and extent of lipid digestion decreased with increasing pectin, methyl cellulose, and chitosan concentrations. The free fatty acids released after 120 min of lipase digestion were 46, 63, and 81% (w/w) for methyl cellulose, pectin, and chitosan, respectively (3.6% (w/w) initial polysaccharide), indicating that methyl cellulose had the highest capacity to inhibit lipid digestion, followed by pectin, and then chitosan. The impact of the polysaccharides on lipid digestion was attributed to their ability to induce droplet flocculation, and/or due to their interactions with molecular species involved in lipid hydrolysis, such as bile salts, fatty acids, and calcium. These results have important implications for understanding the influence of dietary fibers on lipid digestion. The control of lipid digestibility within the gastrointestinal tract might be important for the development of reduced-calorie emulsion-based functional food products.

  10. Simulating Dinosaur Digestion in the Classroom.

    ERIC Educational Resources Information Center

    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,…

  11. Helping Children Overcome Reading Difficulties. ERIC Digest.

    ERIC Educational Resources Information Center

    Smith, Carl B.; Sensenbaugh, Roger

    This digest discusses children with reading difficulties and how these children can be helped to read and learn more effectively. The digest offers a definition and discussion of dyslexia, examines instructional conditions that help the reading comprehension of children labeled as learning disabled, offers suggestions for choosing helpful reading…

  12. Online Resources for Teaching Shakespeare. ERIC Digest.

    ERIC Educational Resources Information Center

    Stoicheva, Mila

    To assist educators in effectively teaching the works of such a critical author as William Shakespeare, this Digest identifies and describes some of the most significant and useful online resources. The digest notes that the sites were chosen on the basis of their technical excellence, purpose, content, authorship, and general usefulness for…

  13. Elastase Digestion of Demembranated Sperm Flagella

    NASA Astrophysics Data System (ADS)

    Brokaw, C. J.

    1980-03-01

    The changes in adenosine triphosphate-reactivated motility resulting from digestion of Triton-demembranated sea urchin sperm flagella by elastase are those expected if the elastic interdoublet linkages between flagellar microtubules are particularly sensitive to digestion by elastase and take part in regulating the amplitude of flagellar bending.

  14. Building Databases for Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Klausmeier, Jane A.

    This digest provides a brief explanation of what a database is; explains how a database can be used; identifies important factors that should be considered when choosing database management system software; and provides citations to sources for finding reviews and evaluations of database management software. The digest is concerned primarily with…

  15. Video Games: Research, Ratings, Recommendations. ERIC Digest.

    ERIC Educational Resources Information Center

    Cesarone, Bernard

    This Digest reviews research on the demographics and effects of video game playing, discusses game rating systems, and offers recommendations for parents. The Digest begins by discussing research on the time children spend playing electronic games, which shows that younger children's game playing at home (90% of fourth-graders played at least one…

  16. Trends in Peace Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Johnson, Marcia L.

    This ERIC Digest reviews the development and current status of peace education in the United States. After briefly surveying the peace education movement from its origins with a small group of educators in New England in the 1800s through its stigmatization as being anti-American during periods of hot and cold war, the Digest devotes more…

  17. La Disciplina Positiva (Positive Discipline). ERIC Digest.

    ERIC Educational Resources Information Center

    ERIC Clearinghouse on Elementary and Early Childhood Education, Urbana, IL.

    This ERIC Digest suggests methods and language that can be used in handling difficult, but common, situations involving young children. The digest explains 12 methods of disciplining children that promote children's self-worth. These methods are: (1) showing children that the reasons for their actions are understood; (2) stating reasons; (3)…

  18. The Writer's Digest Guide to Good Writing.

    ERIC Educational Resources Information Center

    Clark, Thomas, Ed.; And Others

    Marking "Writer's Digest"'s upcoming 75th anniversary, this book presents a collection of the best writing instruction, advice, and inspiration written by famous and not-so-famous writers and published in the magazine from the 1920s to the 1990s. The 49 selections in the book are arranged chronologically and address: (1) selecting an…

  19. Effect of digestion time on anaerobic digestion with high ammonia concentration

    NASA Astrophysics Data System (ADS)

    Oktavitri, Nur Indradewi; Purnobasuki, Hery; Kuncoro, Eko Prasetyo; Purnamasari, Indah; Semma Hadinnata, P.

    2016-03-01

    Anaerobic digestion was developed to treat high concentration organic compound efficiently in certain Digestion Time (DT). High ammonia concentration could influenced removal organic compound in digestion. This bench scale study investigated the effect of digestion time on anaerobic batch reactor with high ammonia concentration. Total Ammonia Nitrogen (TAN) concentration was adjusted 4000 and 5000 mg/1, Digestion time was ranged from 0-26 d, operation temperature was ranged from 28-29°C, inoculum was collected from slaughter house sludge. The degradation of Chemical Oxygen Demand (COD) correlated with digestion time. The concentration of TAN from synthetic wastewater contain 5000 mg/1 of TAN more fluctuated than those use 4000 mg/1 of TAN. However, the biogas production from wastewater contained 4000 mg/1 of TAN gradually increased until 24 d of DT. The reactor contain 5000 mg/1 of TAN only growth until 12 d and steady state at over 12 d of digestion time.

  20. Analysis of methane emissions from digested sludge.

    PubMed

    Schaum, C; Fundneider, T; Cornel, P

    2016-01-01

    The energetic use of sewage sludge is an important step in the generation of electricity and heat within a wastewater treatment plant (WWTP). For a holistic approach, methane emissions derived from anaerobic treatment have to be considered. Measurements show that methane dissolved in digested sludge can be analyzed via the vacuum salting out degassing method. At different WWTPs, dissolved methane was measured, showing a concentration range of approximately 7-37 mg CH4/L. The average concentration of dissolved methane in mesophilic digested sludge was approximately 29 mg CH4/L, which corresponds to an estimated yearly specific load of approximately 14-21 g CH4 per population equivalent. Comparisons between continuous and discontinuous digester feeding show that a temporary rise in the volume load causes increased concentrations of dissolved methane. Investigations using an industrial-scale digestion plant, consisting of three digestion tank operated in series, show comparable results.

  1. Effect of processing on polyamine content and bioactive peptides released after in vitro gastrointestinal digestion of infant formulas.

    PubMed

    Gómez-Gallego, C; Recio, I; Gómez-Gómez, V; Ortuño, I; Bernal, M J; Ros, G; Periago, M J

    2016-02-01

    This study examined the influence of processing on polyamines and peptide release after the digestion of a commercial infant formula designed for children during the first months of life. Polyamine oxidase activity was not suppressed during the manufacturing process, which implicates that polyamine concentrations were reduced over time and during infant formula self-life. In gel electrophoresis, in vitro gastrointestinal digestion of samples with reduced amount of enzymes and time of digestion shows an increase in protein digestibility, reflected in the increase in nonprotein nitrogen after digestion and the disappearance of β-lactoglobulin and α-lactalbumin bands in gel electrophoresis. Depending on the sample, between 22 and 87 peptides were identified after gastrointestinal digestion. A peptide from β-casein f(98-105) with the sequence VKEAMAPK and antioxidant activity appeared in all of the samples. Other peptides with antioxidant, immunomodulatory, and antimicrobial activities were frequently found, which could have an effect on infant health. The present study confirms that the infant formula manufacturing process determines the polyamine content and peptidic profile after digestion of the infant formula. Because compositional dissimilarity between human milk and infant formula in polyamines and proteins could be responsible for some of the differences in health reported between breast-fed and formula-fed children, these changes must be taken into consideration because they may have a great effect on infant nutrition and development.

  2. Digestion of Crystalline Silicotitanate (CST)

    SciTech Connect

    DARREL, WALKER

    2004-11-04

    Researchers tested methods for chemically dissolving crystalline silicotitanate (CST) as a substitute for mechanical grinding to reduce particle size before vitrification. Testing used the commercially available form of CST, UOP IONSIV(R) IE-911. Reduction of the particle size to a range similar to that of the glass frit used by the Defense Waste Processing Facility (DWPF) could reduce problems with coupling cesium ion exchange to the vitrification process. This study found that IONSIV(R) IE-911 dissolves completely using a combination of acid, hydrogen peroxide, and fluoride ion. Neutralization of the resulting acidic solution precipitates components of the IONSIV(R) IE-911. Digestion requires extremely corrosive conditions. Also, large particles may reform during neutralization, and the initiation and rate of gas generation are unpredictable. Therefore, the method is not recommended as a substitute for mechanical grinding.

  3. Anaerobic digestion of alcohol stillage

    SciTech Connect

    Binder, L.K.

    1981-01-01

    In the production of ethanol from grain, the distillation step produces a residue of distillers grains or stillage that contains greater than 90% water and is currently dried and used as a cattle feed supplement. Experimental work was carried out on the anaerobic digestion of the stillage to determine the feasibility of using the CH/sub 4/ produced to supply the energy required in the ethanol distillation step. The fermentation characteristics of the stillage were studied, and the amount of CH/sub 4/ produced was determined. Based on an economic analysis, the value of the pressed solids fraction of the stillage as feed is much greater than the potential return from producing CH/sub 4/.

  4. A Digest of Nonproliferation Literature.

    SciTech Connect

    Duggan, Ruth A

    2006-04-01

    In preparation for the 2005 US/Russian Weapons Laboratories Directors Meeting, the six laboratories participating in the meeting endeavored to develop a strategy for nonproliferation technology research and development. A literature review was conducted to identify possible areas of technical collaboration and technology opportunities associated with improving nonproliferation associated with the civilian nuclear fuel cycle. The issue of multinationalization of the nuclear fuel cycle was also researched. This digest is the compilation of one-page summaries used by management of the three US nuclear weapons laboratories in preparation for strategy development. Where possible, the Web site address of the complete paper is referenced.3 AcknowledgementsThe author wishes to thank Jessica Ruyle, Nancy Orlando-Gay, and Barbara Dry for their research assistance and contributions.4

  5. Understanding Sensory Integration. ERIC Digest.

    ERIC Educational Resources Information Center

    DiMatties, Marie E.; Sammons, Jennifer H.

    This brief paper summarizes what is known about sensory integration and sensory integration dysfunction (DSI). It outlines evaluation of DSI, treatment approaches, and implications for parents and teachers, including compensatory strategies for minimizing the impact of DSI on a child's life. Review of origins of sensory integration theory in the…

  6. An improved trypsin digestion method minimizes digestion-induced modifications on proteins.

    PubMed

    Ren, Da; Pipes, Gary D; Liu, Dingjiang; Shih, Liang-Yu; Nichols, Andrew C; Treuheit, Michael J; Brems, David N; Bondarenko, Pavel V

    2009-09-01

    Trypsin digestion can induce artificial modifications such as asparagine deamidation and N-terminal glutamine cyclization on proteins due to the temperature and the alkaline pH buffers used during digestion. The amount of these artificial modifications is directly proportional to the incubation time of protein samples in the reduction/alkylation buffer and, more important, in the digestion buffer where the peptides are completely solvent exposed. To minimize these artificial modifications, we focused on minimizing the trypsin digestion time by maximizing trypsin activity. Trypsin activity was optimized by the complete removal of guanidine, which is a known trypsin inhibitor, from the digestion buffer. As a result, near complete trypsin digestion was achieved on reduced and alkylated immunoglobulin gamma molecules in 30min. The protein tryptic fragments and their modification products were analyzed and quantified by reversed-phase liquid chromatography/tandem mass spectrometry using an in-line LTQ Orbitrap mass spectrometer. The reduction and alkylation reaction time was also minimized by monitoring the completeness of the reaction using a high-resolution time-of-flight mass spectrometer. Using this 30-min in-solution trypsin digestion method, little protocol-induced deamidation or N-terminal glutamine cyclization product was observed and cleaner tryptic maps were obtained due to less trypsin self-digestion and fewer nonspecific cleavages. The throughput of trypsin digestion was also improved significantly compared with conventional trypsin digestion methods.

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

    PubMed

    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 < 0.0001) for all AA when all 16 MBM samples were included in the analysis. However, when the MBM samples with the 2 lowest and the 2 highest rooster 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.

  8. Poultry waste digester. Final progress report

    SciTech Connect

    Shih, J.C.H.

    1983-01-01

    A simple and low-cost poultry waste digester (PWD) was constructed at North Carolina State University's Poultry Research Farm at Raleigh, N.C. The PWD system was designed to process a daily output of 600 kg of manure from 4000 caged laying hens. The system consisted of two digesters connected in series, a heating system, a hot water tank, and other metering equipment. The primary and secondary digesters were horizontal cylinders located partially below ground level. They were made of Red Mud plastic lining, supported in the insulated trenches, and covered with insulated roofs. The primary digester volume was 15 m/sup 3/ with an 8 m/sup 3/ liquid volume and a gas head-space above the liquid. The secondary digester volume was 30 m/sup 3/ with a 16 m/sup 3/ liquid volume. The temperature (50/sup 0/C) of the primary digester was maintained by the hot dilution water added with manure and a SolaRoll heating mat laid underneath the plastic lining. The design, operation, performance, energy balance, and economics of the digester are discussed and evaluated in this final progress report.

  9. Nanobiocatalysis for protein digestion in proteomic analysis

    SciTech Connect

    Kim, Jungbae; Kim, Byoung Chan; Lopez-Ferrer, Daniel; Petritis, Konstantinos; Smith, Richard D.

    2010-02-01

    The process of protein digestion is a critical step for successful protein identification in the bottom-up proteomic analysis. To substitute the present practice of in-solution protein digestion, which is long, tedious, and difficult to automate, a lot of efforts have been dedicated for the development of a rapid, recyclable and automated digestion system. Recent advances of nanobiocatalytic approaches have improved the performance of protein digestion by using various nanomaterials such as nanoporous materials, magnetic nanoparticles, and polymer nanofibers. Especially, the unprecedented success of trypsin stabilization in the form of trypsin-coated nanofibers, showing no activity decrease under repeated uses for one year and retaining good resistance to proteolysis, has demonstrated its great potential to be employed in the development of automated, high-throughput, and on-line digestion systems. This review discusses recent developments of nanobiocatalytic approaches for the improved performance of protein digestion in speed, detection sensitivity, recyclability, and trypsin stability. In addition, we also introduce the protein digestions under unconventional energy inputs for protein denaturation and the development of microfluidic enzyme reactors that can benefit from recent successes of these nanobiocatalytic approaches.

  10. Pepsin-Digestibility of Contaminated Estuarine Sediments

    NASA Astrophysics Data System (ADS)

    Turner, A.; Henon, D. N.; Dale, J. L. L.

    2001-11-01

    A standard method for the in vitro digestion of animal protein feeds (2% pepsin in 0·075 N HCl) has been applied to contaminated sediments in order to evaluate a ' bioavailable ' or ' gut-soluble ' fraction of carbon, nitrogen and mineral and trace metals. For most sediment samples, considerably more nitrogen was digested than carbon because of enzymatic digestion of proteinaceous material, and the sequence of metal ' gut-solubility ' was: Cu, Zn>Mn>Fe≫Al. The principal mechanism of metal release appears to be hydrochloric acid digestion of inorganic hydrogenous host phases (e.g. amorphous Fe and Mn oxides), although release of Cu via surface complexation with pepsin molecules may also be significant, and the amount of metal digested enzymatically is restricted to a small and unquantifiable fraction associated with proteinaceous material. Dilute HCl alone does not, however, afford a suitable surrogate for assessing a gut-soluble fraction of metal because enzymatic and acid digestions exhibit synergistic effects, including possible re-adsorption of pepsin-metal complexes under acidic conditions, and exposure and acid attack of otherwise inaccessible hydrogenous material following enzymatic digestion of organic matter.

  11. Fate of Trace Metals in Anaerobic Digestion.

    PubMed

    Fermoso, F G; van Hullebusch, E D; Guibaud, G; Collins, G; Svensson, B H; Carliell-Marquet, C; Vink, J P M; Esposito, G; Frunzo, L

    2015-01-01

    A challenging, and largely uncharted, area of research in the field of anaerobic digestion science and technology is in understanding the roles of trace metals in enabling biogas production. This is a major knowledge gap and a multifaceted problem involving metal chemistry; physical interactions of metal and solids; microbiology; and technology optimization. Moreover, the fate of trace metals, and the chemical speciation and transport of trace metals in environments--often agricultural lands receiving discharge waters from anaerobic digestion processes--simultaneously represents challenges for environmental protection and opportunities to close process loops in anaerobic digestion.

  12. Robust regulation of anaerobic digestion processes.

    PubMed

    Mailleret, L; Bernard, O; Steyer, J P

    2003-01-01

    This paper deals with the problem of controlling anaerobic digestion processes. A two-step (i.e. acidogenesis-methanization) mass balance model is considered for a 1 m3 fixed bed digester treating industrial wine distillery wastewater. The control law aims at regulating the organic pollution level while avoiding washout of biomass. To this end, a simple output feedback controller is considered which regulates a variable strongly related to the Chemical Oxygen Demand (COD). Numerical simulations assuming noisy measurements first illustrate the robustness of this control procedure. Then, the regulating procedure is implemented on the considered anaerobic digestion process in order to validate and demonstrate its efficiency in real life experiments.

  13. Digestive sensitivity varies according to size of dogs: a review.

    PubMed

    Weber, M P; Biourge, V C; Nguyen, P G

    2017-02-01

    Field observations on food tolerance have repeatedly shown that when fed an identical diet, large breed (>25 kg) dogs present softer and moister faeces than small breed ones (<15 kg). The purpose of this review is to highlight the findings of four PhD theses, carried out between 1998 and 2013, whose objectives were to investigate the anatomical and physiological peculiarities that would explain, at least in part, this observation, as well as their nutritional implication. This work showed that large breed dogs, in contrast with smaller breeds, present a highly developed caecum and colon, which could explain the relatively longer colonic transit time. A prolonged colonic transit time could explain higher colonic fermentative activity, as supported by higher faecal concentrations of fermentative by-products. This effect would be reinforced by increased intestinal permeability and reduced sodium net-absorption. Taken together, these elements could be a possible cause of higher digestive sensitivity in large breed dogs. When prescribing a diet to a small or large breed dog, several aspects of the formulation must be taken into account. For a large breed dog, the general goal is to limit any ingredient that could increase the level of fermentable undigested residues and, in fine, exacerbate colonic fermentation. Highly digestible sources of proteins and starches are therefore strongly recommended to maintain an optimal digestive tolerance. Fermentable fibre sources (i.e. beet pulp and FOS) must also be used in limited quantity in their diet. Conversely, the incorporation of non-fermentable fibre (i.e. cellulose) appears useful to increase their stool quality. For a small breed dog, the general objective is to minimize any ingredient that could excessively limit colonic fermentation and induce in fine constipation. Purified starches and cellulose are therefore not really suitable for them. In contrast, cereals flours as well as non-fermentable fibre provided by cereals

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

    PubMed

    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 (P<0.05) more longer chain (C≥10) fatty acids were present in the digesta of rats gavaged with raw (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.

  15. Palliative care - fluid, food, and digestion

    MedlinePlus

    ... gov/ency/patientinstructions/000531.htm Palliative care - fluid, food, and digestion To use the sharing features on ... When Your Body Has Problems Handling Fluids and Food It is normal for a person who has ...

  16. Photoenhanced anaerobic digestion of organic acids

    DOEpatents

    Weaver, Paul F.

    1990-01-01

    A process is described for rapid conversion of organic acids and alcohols anaerobic digesters into hydrogen and carbon dioxide, the optimal precursor substrates for production of methane. The process includes addition of photosynthetic bacteria to the digester and exposure of the bacteria to radiant energy (e.g., solar energy). The process also increases the pH stability of the digester to prevent failure of the digester. Preferred substrates for photosynthetic bacteria are the organic acid and alcohol waste products of fermentative bacteria. In mixed culture with methanogenic bacteria or in defined co-culture with non-aceticlastic methanogenic bacteria, photosynthetic bacteria are capable of facilitating the conversion or organic acids and alcohols into methane with low levels of light energy input.

  17. Toxicants inhibiting anaerobic digestion: a review.

    PubMed

    Chen, Jian Lin; Ortiz, Raphael; Steele, Terry W J; Stuckey, David C

    2014-12-01

    Anaerobic digestion is increasingly being used to treat wastes from many sources because of its manifold advantages over aerobic treatment, e.g. low sludge production and low energy requirements. However, anaerobic digestion is sensitive to toxicants, and a wide range of compounds can inhibit the process and cause upset or failure. Substantial research has been carried out over the years to identify specific inhibitors/toxicants, and their mechanism of toxicity in anaerobic digestion. In this review we present a detailed and critical summary of research on the inhibition of anaerobic processes by specific organic toxicants (e.g., chlorophenols, halogenated aliphatics and long chain fatty acids), inorganic toxicants (e.g., ammonia, sulfide and heavy metals) and in particular, nanomaterials, focusing on the mechanism of their inhibition/toxicity. A better understanding of the fundamental mechanisms behind inhibition/toxicity will enhance the wider application of anaerobic digestion.

  18. Nuclear Regulatory Commission 1989 Information Digest

    SciTech Connect

    None,

    1989-03-01

    The Nuclear Regulatory Commission 1989 Information Digest provides summary information regarding the US Nuclear Regulatory Commission, its regulatory responsibilities, and areas licensed by the Commission. This is the first of an annual publication for the general use of the NRC staff and is available to the public. The Digest is divided into two parts: the first presents an overview of the US Nuclear Regulatory Commission and the second provides data on NRC commercial nuclear reactor licensees and commercial nuclear power reactors worldwide.

  19. Digestive Enzyme Supplementation in Gastrointestinal Diseases

    PubMed Central

    Ianiro, Gianluca; Pecere, Silvia; Giorgio, Valentina; Gasbarrini, Antonio; Cammarota, Giovanni

    2016-01-01

    Background: Digestive enzymes are able to break down proteins and carbohydrates and lipids, and their supplementation may play a role in the management of digestive disorders, from lactose intolerance to cystic fibrosis. To date, several formulations of digestive enzymes are available on the market, being different each other in terms of enzyme type, source and origin, and dosage. Methods: This review, performed through a non-systematic search of the available literature, will provide an overview of the current knowledge of digestive enzyme supplementation in gastrointestinal disorders, discussion of the use of pancreatic enzymes, lactase (β-galactosidase) and conjugated bile acids, and also exploring the future perspective of digestive enzyme supplementation. Results: Currently, the animal-derived enzymes represent an established standard of care, however the growing study of plant-based and microbe-derived enzymes offers great promise in the advancement of digestive enzyme therapy. Conclusion: New frontiers of enzyme replacement are being evaluated also in the treatment of diseases not specifically related to enzyme deficiency, whereas the combination of different enzymes might constitute an intriguing therapeutic option in the future. PMID:26806042

  20. Anaerobic sludge digestion with a biocatalytic additive

    SciTech Connect

    Ghosh, S.; Henry, M.P.; Fedde, P.A.

    1982-01-01

    The objective of this research was to evaluate the effects of a lactobacillus additive an anaerobic sludge digestion under normal, variable, and overload operating conditions. The additive was a whey fermentation product of an acid-tolerant strain of Lactobacillus acidophilus fortified with CaCO/sub 3/, (NH/sub 4/)/sub 2/HPO/sub 4/, ferrous lactate, and lactic acid. The lactobacillus additive is multifunctional in nature and provides growth factors, metabolic intermediates, and enzymes needed for substrate degradation and cellular synthesis. The experimental work consisted of several pairs of parallel mesophilic (35/sup 0/C) digestion runs (control and test) conducted in five experimental phases. Baseline runs without the additive showed that the two experimental digesters had the same methane content, gas production rate (GPR), and ethane yield. The effect of the additive was to increase methane yield and GPR by about 5% (which was statistically significant) during digester operation at a loading rate (LR) of 3.2 kg VS/m/sup 3/-day and a hydraulic retention time (HRT) of 14 days. Data collected from the various experimental phases showed that the biochemical additive increased methane yield, gas production rate, and VS reduction, and decreased volatile acids accumulation. In addition, it enhanced digester buffer capacity and improved the fertilizer value and dewatering characteristics of the digested residue.

  1. Phage diversity in a methanogenic digester.

    PubMed

    Park, M-O; Ikenaga, H; Watanabe, K

    2007-01-01

    It has been shown that phages are present in natural and engineered ecosystems and influence the structure and performance of prokaryotic communities. However, little has been known about phages occurring in anaerobic ecosystems, including those in methanogenic digesters for waste treatment. This study investigated phages produced in an upflow anaerobic sludge blanket methanogenic digester treating brewery wastes. Phage-like particles (PLPs) in the influent and effluent of the digester were concentrated and purified by sequential filtration and quantified and characterized by transmission electron microscopy (TEM), fluorescence assay, and field inversion gel electrophoresis (FIGE). Results indicate that numbers of PLPs in the effluent of the digester exceeded 1 x 10(9) L-1 and at least 10 times greater than those in the influent, suggesting that substantial amounts of PLPs were produced in the digester. A production rate of the PLPs was estimated at least 5.2 x 10(7) PLPs day-1 L-1. TEM and FIGE showed that a variety of phages were produced in the digester, including those affiliated with Siphoviridae, Myoviridae, and Cystoviridae.

  2. Potential misinterpretation of the nutritional value of dietary fiber: correcting fiber digestibility values for nondietary gut-interfering material.

    PubMed

    Montoya, Carlos A; Henare, Sharon J; Rutherfurd, Shane M; Moughan, Paul J

    2016-08-01

    The aim of this review is to identify the origin and implications of a nondietary material present in digesta and feces that interferes with the determination of dietary fiber in gastrointestinal contents. Negative values for ileal and fecal digestibility of dietary fiber are commonly reported in the literature for monogastric animal species, including humans. As negative values are not possible physiologically, this suggests the existence of a nondietary material in the gastrointestinal contents and feces that interferes with the accurate determination of dietary fiber digestibility when conventional methods of fiber determination are applied. To date, little attention has been given to this nondietary interfering material, which appears to be influenced by the type and concentration of fiber in the diet. Interestingly, estimates of dietary fiber digestibility increase substantially when corrected for the nondietary interfering material, which suggests that currently reported values underestimate the digestibility of dietary fiber and may misrepresent where, in the digestive tract, fermentation of fiber occurs. A new perspective of dietary fiber digestion in the gastrointestinal tract is developing, leading to a better understanding of the contribution of dietary fiber to health.

  3. Influence of two plant extracts on broilers performance, digestibility, and digestive organ size.

    PubMed

    Hernández, F; Madrid, J; García, V; Orengo, J; Megías, M D

    2004-02-01

    A 42-d trial was conducted to study the influence of 2 plant extracts on performance, digestibility, and digestive organ weights in broilers. The feeding program consisted of a starter diet until 21 d and a finisher diet until 42 d. There were 4 treatment groups: control; 10 ppm avilamycin (AB); 200 ppm essential oil extract (EOE) from oregano, cinnamon, and pepper; and 5,000 ppm Labiatae extract (LE) from sage, thyme, and rosemary. No differences in feed intake or feed conversion were observed. From 14 to 21 d of age, broilers fed the LE diet grew faster than the broilers fed the control or EOE feeds (68.8 vs. 63.9 and 61.6 g/d, respectively). Antibiotic and plant extract supplementation improved apparent whole-tract and ileal digestibility of the nutrients. For starter feed, LE supplementation improved apparent fecal digestibility of DM (P < 0.01), and all additives increased ether extract digestibility (P < 0.001). However, no effect was detected for CP digestibility (P > 0.1). At the ileal level, the AB, EOE, and LE supplementation of the starter feed increased DM and starch (P < 0.01) digestibility but not CP digestibility (P > 0.1). All additives improved apparent fecal digestibility of DM and CP of the finisher diet. No differences were observed for proventriculus, gizzard, liver, pancreas, or large or small intestine weight. In the present study, both plant extracts improved the digestibility of the feeds for broilers. The effect of different additives on digestibility improved the performance slightly, but this effect was not statistically significant.

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

    PubMed

    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.

  5. Student Teachers' Ways of Thinking and Ways of Understanding Digestion and the Digestive System in Biology

    ERIC Educational Resources Information Center

    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…

  6. Acid digestion of combustible radioactive wastes

    SciTech Connect

    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/sup 6/ and the overall DF from the digester to the off-gas stack was >1 x 10/sup 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/sup 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/sub 2/) during digestion, reaction with chlorides in waste (NO/sub 2/stack was > 1.5 x 10/sup 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.

  7. Residual biogas potential from the storage tanks of non-separated digestate and digested liquid fraction.

    PubMed

    Gioelli, F; Dinuccio, E; Balsari, P

    2011-11-01

    Biogas plants daily produce enormous volumes of digestate that can be handled in its raw form or after mechanical separation. In Italy, effluents are usually stored within aboveground, uncovered tanks, which make them potential emitters of biogas into the atmosphere. The purpose of this study was to estimate the amount of biogas emitted to the atmosphere during the storage phase of non-separated digestate and digested liquid fraction. The trials were performed at two northwest Italy 1 MWel. biogas plants. A floating system for the residual biogas recovery, and a set of three wind tunnels for NH3 emission measurement were used. The experiment demonstrated significant loss to the atmosphere for each of the gases; specifically, on average, 19.5 and 7.90 N m3 biogas MWhel.(-1) were emitted daily from the storage tanks of non-separated digestate and digested liquid fraction, respectively.

  8. Lactose digestion from yogurt: mechanism and relevance.

    PubMed

    Savaiano, Dennis A

    2014-05-01

    Yogurt is traditionally consumed throughout the world among populations who are seemingly unable to digest lactose. This review provides a historical overview of the studies that show lactose digestion and tolerance from yogurt by lactose-intolerant people. The lactose in yogurt is digested more efficiently than other dairy sources of lactose because the bacteria inherent in yogurt assist with its digestion. The bacterial lactase survives the acidic conditions of the stomach, apparently being physically protected within the bacterial cells and facilitated by the buffering capacity of yogurt. The increasing pH as the yogurt enters the small intestine and a slower gastrointestinal transit time allow the bacterial lactase to be active, digesting lactose from yogurt sufficiently to prevent symptoms in lactose-intolerant people. There is little difference in the lactase capability of different commercial yogurts, because they apparently contain Lactobacillus bulgaricus and Streptococcus thermophilus in sufficient quantities (10(8) bacteria/mL). However, Lactobacillus acidophilus appears to require cell membrane disruption to physically release the lactase. Compared with unflavored yogurts, flavored yogurts appear to exhibit somewhat reduced lactase activity but are still well tolerated.

  9. Antihypertensive properties of spinach leaf protein digests.

    PubMed

    Yang, Yanjun; Marczak, Ewa D; Usui, Hachiro; Kawamura, Yukio; Yoshikawa, Masaaki

    2004-04-21

    Leaf protein containing approximately 50% rubisco (ribulose bisphosphate carboxylase/oxygenase) was obtained from fresh spinach leaf with the use of a simple extraction method. Pepsin and pepsin-pancreatin digests of spinach leaf protein have potent angiotensin-I converting enzyme inhibitory properties with IC(50) values of 56 and 120 microg/mL, respectively. Both digests of leaf protein have antihypertensive effects after oral administration to spontaneously hypertensive rats (SHR) with minimum effective doses of 0.25 and 0.5 g/kg, respectively. The maximum antihypertensive effect for the pepsin digest was observed 4 h after oral administration, while for the pepsin-pancreatin digest, the maximum effect was observed 2 h after oral administration. Undigested spinach leaf protein did not exert any significant antihypertensive effect after oral administration to SHR at doses of 0.5 and 1 g/kg. Obtained results show that the pepsin digest of leaf protein may be useful in treatment of hypertension.

  10. The usability of digestate in organic farming.

    PubMed

    Clements, L J; Salter, A M; Banks, C J; Poppy, G M

    2012-01-01

    As organic farming prohibits the use of synthetic fertilisers, animal slurries and manures must be used. Digestate offers an alternative to these and this study reports on three experiments conducted to determine its usability in terms of: (1) the effect on earthworm populations, (2) its fertilising effects on Italian Ryegrass and wild Creeping Thistle, and (3) the suppression effects digestate has on weed emergence. The results for digestate application to field plots were intermediate between slurry and no treatment for earthworm attraction and wild thistle suppression. In glasshouse trials it led to increased ryegrass growth compared with undigested slurry. Analysis showed that the digestate had improved nitrogen availability, leading to increased plant growth, but a reduced organic matter content compared with the slurry, leading to a positive though less beneficial impact on the earthworms. Digestate therefore provides a suitable fertiliser for organic farming. This suitability could be improved by drying or separation to increase the OM content making its properties closer to those of slurry whilst still retaining the higher content of plant available nitrogen.

  11. [Functional and motor digestive disorders].

    PubMed

    Mearin, Fermín; Rey, Enrique; Balboa, Agustín

    2013-10-01

    This article discusses the most interesting studies on functional and motility gastrointestinal disorders presented in Digestive Diseases Week (DDW) in 2013. New data were reported on the clinical importance of functional gastrointestinal disorders (FGID) and on how they can produce numerous disturbances such as inflammatory bowel disease. These disturbances are associated with somatic functional disease and particularly with fatigue. In addition, new data have emerged on the physiopathology of these disorders, with some studies reporting that environmental factors and events in early infancy can favor their development. Data were also presented on how bile acids can increase susceptibility to diarrhea in patients with irritable bowel syndrome (IBS) and on how the type of food intake can favor the development of symptoms. More data are available on the presence of underlying celiac disease in patients with IBS, which should prompt us to investigate this disease in our patients. Likewise, indiscriminate application of a gluten-free diet in patients with IBS has been shown not to produce a clear improvement. Regarding the physiopathology of functional dyspepsia (FD), results have been presented on how psychological factors can modify gastric accommodation and how this is in turn related to visceral hypersensitivity and gastric emptying. Regarding therapy, mirtazapine can improve symptoms and lead to weight gain in patients with severe FD and substantial weight loss. Results were presented on new drugs for IBS such as ibodutant and on old drugs with new applications such as mesalazine and ebastine. The antinociceptive effect of linaclotide is now better understood and a meta-analysis has shown its effectiveness in IBS with constipation as the main symptom. In patients with constipation, pelvic floor dysynergy can be diagnosed by a simple clinical interview and rectal touch. More data are available on the efficacy of prucalopride (which has been shown to accelerate

  12. Microalgal Cultivation in Treating Liquid Digestate from Biogas Systems.

    PubMed

    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.

  13. Ecological physiology of diet and digestive systems.

    PubMed

    Karasov, William H; Martínez del Rio, Carlos; Caviedes-Vidal, Enrique

    2011-01-01

    The morphological and functional design of gastrointestinal tracts of many vertebrates and invertebrates can be explained largely by the interaction between diet chemical constituents and principles of economic design, both of which are embodied in chemical reactor models of gut function. Natural selection seems to have led to the expression of digestive features that approximately match digestive capacities with dietary loads while exhibiting relatively modest excess. Mechanisms explaining differences in hydrolase activity between populations and species include gene copy number variations and single-nucleotide polymorphisms. In many animals, both transcriptional adjustment and posttranscriptional adjustment mediate phenotypic flexibility in the expression of intestinal hydrolases and transporters in response to dietary signals. Digestive performance of animals depends also on their gastrointestinal microbiome. The microbiome seems to be characterized by large beta diversity among hosts and by a common core metagenome and seems to differ flexibly among animals with different diets.

  14. Sophisticated digestive systems in early arthropods.

    PubMed

    Vannier, Jean; Liu, Jianni; Lerosey-Aubril, Rudy; Vinther, Jakob; Daley, Allison C

    2014-05-02

    Understanding the way in which animals diversified and radiated during their early evolutionary history remains one of the most captivating of scientific challenges. Integral to this is the 'Cambrian explosion', which records the rapid emergence of most animal phyla, and for which the triggering and accelerating factors, whether environmental or biological, are still unclear. Here we describe exceptionally well-preserved complex digestive organs in early arthropods from the early Cambrian of China and Greenland with functional similarities to certain modern crustaceans and trace these structures through the early evolutionary lineage of fossil arthropods. These digestive structures are assumed to have allowed for more efficient digestion and metabolism, promoting carnivory and macrophagy in early arthropods via predation or scavenging. This key innovation may have been of critical importance in the radiation and ecological success of Arthropoda, which has been the most diverse and abundant invertebrate phylum since the Cambrian.

  15. Nuclear Regulatory Commission Information Digest, 1991 edition

    SciTech Connect

    Olive, K L

    1991-03-01

    The Nuclear Regulatory Commission Information Digest provides a summary of information about the US Nuclear Regulatory Commission (NRC), NRC's regulatory responsibilities, and the areas NRC licenses. This digest is a compilation of NRC-related data and is designed to provide a quick reference to major facts about the agency and the industry it regulates. In general, the data cover 1975 through 1990, with exceptions noted. For operating US commercial nuclear power reactors, information on generating capacity and average capacity factor is obtained from Monthly Operating Reports submitted to the NRC directly by the licensee. This information is reviewed for consistency only. No independent validation and/or verification is performed by the NRC. For detailed and complete information about tables and figures, refer to the source publications. This digest is published annually for the general use of the NRC staff and is available to the public. 30 figs., 12 tabs.

  16. FCPP application to utilize anaerobic digester gas

    SciTech Connect

    Nakayama, Yoshio; Kusama, Nobuyuki; Wada, Katsuya

    1996-12-31

    Toshiba and a municipal organization of Yokohama city are jointly conducting a program to utilize ADG (Anaerobic Digester Gas) more effectively. ADG which contains about 60% methane is produced by anaerobic digestion of waste water treatment sludge and has been used as an energy source for heating digestion tanks in sewage treatment plants and/or for combustion engine fuel. This program is focused on operating a commercial Phosphoric Acid Fuel Cell (PAFC) power plant on ADG because of its inherently high fuel efficiency and low emissions characteristics. According to the following joint program, we have successfully demonstrated an ADG fueled FCPP The success of this study promises that the ADG fueled FCPP, an environment-friendly power generation system, will be added to the line-up of PC25{trademark}C applications.

  17. Digestive Physiological Characteristics of the Gobiidae

    PubMed Central

    Hur, Sang-Woo; Kim, Shin-Kwon; Kim, Dae-Jung; Lee, Bae-Ik; Park, Su-Jin; Hwang, Hyung-Gyu; Jun, Je-Cheon; Myeong, Jeong-In; Lee, Chi-Hoon; Lee, Young-Don

    2016-01-01

    In this study, we investigated the characteristics of CCK-producing cells and mucus-secreting goblet cells with respect to stomach fish and stomachless fish of the Gobiidae in order to provide a basis for understanding the digestive physiology. Hairychin goby (Sagamia geneionema), which is stomachless fish, the numbers of mucus-secreting goblet cells is highest in the posterior intestine portion (P<0.05), while CCK-producing cells are scattered throughout the intestine. Gluttonous goby (Chasmichthys gulosus), which is stomach fish, mucus-secreting goblet cells are most abundant in the mid intestine portion (P<0.05), whereas CCK-producing cells are observed only in the anterior and mid intestine portion. Trident goby (Tridentiger obscurus) which is stomach fish, mucus-secreting goblet cells were most abundant in the mid intestine portion (P<0.05). CCK-producing cells are found in the anterior and mid intestine portion. Giurine goby, Rhinogobius giurinus which is also stomach fish, the largest number of mucus-secreting goblet cells showed in anterior intestine portion except for esophagus (P<0.05). CCK-producing cells are present only in the anterior and mid intestine portion. In S. geneionema, digestive action occurs in the posterior intestine portion to protect and functions to activate digestion. In contrast, in C. gulosus, T. obscurus and R. giurinus, their digestive action occurs in the anterior and mid intestine portion to protect and functions to activate digestion. Further studies of the modes of food ingestion by these fish, the contents of their digestive tracts, and the staining characteristics of the goblet cells need to be carried out. PMID:27796002

  18. ArgC-Like Digestion: Complementary or Alternative to Tryptic Digestion?

    PubMed

    Golghalyani, Vahid; Neupärtl, Moritz; Wittig, Ilka; Bahr, Ute; Karas, Michael

    2017-02-03

    Enzymatic digestion of complex protein samples is often performed by use of multiple proteases to improve protein identification and characterization. Combining trypsin with ArgC is one option to enhance sequence coverage in bottom-up proteomics. However, the low selectivity of this endoprotease derogates from the benefit of the combination. Our approach here is to mimic ArgC digestion by chemically modifying all lysine residues in proteins so that trypsin can only cleave C-terminal to arginine. Four different amine modifications, dimethylation, acetylation, propionylation, and carbethoxylation, were tested, and the protocols were optimized. A nearly complete conversion of the primary amines was achieved for all modifications. Tryptic digestion of Escherichia coli lysate proteins after acylation of lysine residues shows the most significant improvement compared with data received from ArgC digest. After propionylation, 9216 unique peptides identified 1439 proteins, which, compared with a conventional tryptic digestion, represents the identification of 150 additional proteins due to a reasonable reduction of the sample complexity and higher fragmentation efficiencies of the peptides. It is therefore concluded that the Arg-C like digestion should no longer be regarded as a complementary approach but forms a viable and superior alternative to the conventional trypsin digestion.

  19. Inactivation of Selected Bacterial Pathogens in Dairy Cattle Manure by Mesophilic Anaerobic Digestion (Balloon Type Digester)

    PubMed Central

    Manyi-Loh, Christy E.; Mamphweli, Sampson N.; Meyer, Edson L.; Okoh, Anthony I.; Makaka, Golden; Simon, Michael

    2014-01-01

    Anaerobic digestion of animal manure in biogas digesters has shown promise as a technology in reducing the microbial load to safe and recommended levels. We sought to treat dairy manure obtained from the Fort Hare Dairy Farm by investigating the survival rates of bacterial pathogens, through a total viable plate count method, before, during and after mesophilic anaerobic digestion. Different microbiological media were inoculated with different serial dilutions of manure samples that were withdrawn from the biogas digester at 3, 7 and 14 day intervals to determine the viable cells. Data obtained indicated that the pathogens of public health importance were 90%–99% reduced in the order: Campylobacter sp. (18 days) < Escherichia coli sp. (62 days) < Salmonella sp. (133 days) from a viable count of 10.1 × 103, 3.6 × 105, 7.4 × 103 to concentrations below the detection limit (DL = 102 cfu/g manure), respectively. This disparity in survival rates may be influenced by the inherent characteristics of these bacteria, available nutrients as well as the stages of the anaerobic digestion process. In addition, the highest p-value i.e., 0.957 for E. coli showed the statistical significance of its model and the strongest correlation between its reductions with days of digestion. In conclusion, the results demonstrated that the specific bacterial pathogens in manure can be considerably reduced through anaerobic digestion after 133 days. PMID:25026086

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

    PubMed

    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.

  1. Effects of various fiber additions on lipid digestion during in vitro digestion of beef patties.

    PubMed

    Hur, S J; Lim, B O; Park, G B; Joo, S T

    2009-01-01

    The purpose of this study was to examine the effect of various fiber additions on lipid digestion during the in vitro digestion of beef patties. The control patties were prepared with 90.5% lean meat and 9.5% tallow. Treatments consisted of 90% lean meat with 9.5% tallow and either 0.5% cellulose, 0.5% chitosan, or 0.5% pectin. The beef patties were then passed through an in vitro digestion model that simulated the composition of the mouth, stomach, and small intestine juices. The change in structure and properties of the lipid droplets was monitored by laser scanning confocal fluorescence microscopy. In general, there was a decrease in lipid droplet diameter as the droplets moved from mouth to stomach to small intestine. The amount of free fatty acid dramatically increased after in vitro digestion in all beef patties. The amount of free fatty acid was, however, lower in beef patties containing chitosan and pectin than other beef patties after in vitro digestion. Beef patties containing various fibers had lower thiobarbituric acid-reactive substances (TBARS) values than samples with no fibers. Among the samples to which fibers were added, chitosan and pectin had lower TBARS than beef patties with cellulose. The cholesterol content decreased after in vitro digestion in all beef patties but was not different among the beef patties before and after in vitro digestion. These results enhance our understanding of the physicochemical and structural changes that occur to ground beef within the gastrointestinal tract.

  2. Digestive Secretion of Dionaea muscipula (Venus's Flytrap).

    PubMed

    Scala, J; Iott, K; Schwab, D W; Semersky, F E

    1969-03-01

    The digestive fluid of Dionaea muscipula has been studied with respect to its protein content as a function of time after entrapment of protein material and some enzymes of the secretion. Maximum secretion of enzyme occurs within the first 3 days of the digestive cycle and protein reaches its maximum at 4 days. Phosphatase, proteinase, nuclease and amylase have been observed in the secretion. The enzymes have acid pH optima and the proteinase has a molecular weight of about 40,000.

  3. Lambda Exonuclease Digestion of CGG Trinucleotide Repeats

    PubMed Central

    Conroy, R.S.; Koretsky, A.P.; Moreland, J.

    2011-01-01

    Fragile X syndrome and other triplet repeat diseases are characterized by an elongation of a repeating DNA triplet. The ensemble-averaged lambda exonuclease digestion rate of different substrates, including one with an elongated FMR1 gene containing 120 CGG repeats, was measured using absorption and fluorescence spectroscopy. Using magnetic tweezers sequence-dependent digestion rates and pausing was measured for individual lambda exonucleases. Within the triplet repeats a lower average and narrower distribution of rates and a higher frequency of pausing was observed. PMID:19562332

  4. Improvement of anaerobic digestion of sludge.

    PubMed

    Dohányos, M; Zábranská, J; Kutil, J; Jenícek, P

    2004-01-01

    Anaerobic digestion improvement can be accomplished by different methods. Besides optimization of the process conditions, pretreatment of input sludge and increase of process temperature is frequently used. The thermophilic process brings a higher solids reduction and biogas production, a high resistance to foaming, no problems with odour, better pathogens destruction and an improvement of the energy balance of the whole treatment plant. Disintegration of excess activated sludge in a lysate centrifuge was proved to cause increase of biogas production in full-scale conditions. The rapid thermal conditioning of digested sludge is an acceptable method of particulate matter disintegration and solubilization.

  5. [Endoscopy simulator for training in digestive endoscopy].

    PubMed

    Bures, Jan; Rejchrt, Stanislav; Tachecí, Ilja; Cyrany, Jirí; Fejfar, Tomás; Douda, Tomás; Kopácová, Marcela

    2012-01-01

    This paper reports on a computer-based simulator (GI Mentor II) used for initial training in digestive endoscopy. The highly sophisticated apparatus employs real endoscopes and virtual accessories. The training programme starts with a group of exercises, specially designed to enhance eye-hand coordination. Interactive computerised simulator contains modules for training in gastroscopy, colonoscopy, endoscopic retrograde cholangio-pancreatography and endoscopic control of gastrointestinal bleeding. Virtual library contains 88 authentic cases of diagnostic and therapeutic procedures. Computer-based endoscopy simulators enable trainees to learn and gain technical endoscopic skills before operating on patients. It has the potential to shorten the learning process to competency in digestive endoscopy.

  6. Anaerobic digestion of municipal solid waste

    SciTech Connect

    Dasgupta, A.; Nemerow, N.L.; Farooq, S.; Daly, E.L.Jr.; Sengupta, S.; Gerrish, H.P.; Wong, K.F.

    1981-01-01

    Filtrate from an anaerobic municipal waste digestion plant at Pompano Beach, Florida, has BOD, COD, and total organic C contents of 1075, 6855, and 1655 mg/L, respectively. The treatment does not inactivate total coliforms; that of the digester slurry and filtrate are 2.3 X 10 to the power of 6 and 1.7 X 10 to the power of 6/100 mL, respectively. The average concentrations of Cr, Cu, Mn, Fe, Ni, and Zn in the filtrate are 0.48, 1.29, 7.29, 32, 0.35, and 11 mg/L, respectively. The filtrate requires treatment prior to discharge.

  7. Packaged digester for treating animal wastes

    SciTech Connect

    Not Available

    1981-11-03

    A new range of packaged digesters to process animal or organic wastes has been developed by Bovis Civil Engineering. The unit, known as the Polygester is suitable for use on factory farms, isolated communities and manufacturing industries. The unit consists of an anaerobic digester together with associated pumps, heat exchangers and pipework ready-assembled on a rigid common chassis and separate gas holder as a packaged system. Based on an undiluted solids input of 11% pig slurry, performance figures show up to 85% reduction of COD, 95% reduction of BOD and 18 m3 of biogas per day (equivalent to about 10 litres fuel oil).

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

    SciTech Connect

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

    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.

  9. Chemical forms of mercury and selenium in fish following digestion with simulated gastric fluid.

    PubMed

    George, Graham N; Singh, Satya P; Prince, Roger C; Pickering, Ingrid J

    2008-11-01

    Fish is a major dietary source of potentially neurotoxic methylmercury compounds for humans. It is also a rich source of essential selenium. We have used in situ mercury L(III)-edge and selenium K-edge X-ray absorption spectroscopy to chemically characterize the methylmercury and selenium in both fresh fish and fish digested with simulated gastric fluid. For the mercury, we confirm our earlier finding [ Harris et al. ( 2003 ) Science 301 , 1203 ] that the methylmercury is coordinated by a single thiolate donor, which resembles cysteine, and for the selenium, we find a mixture of organic forms that resemble selenomethionine and an aliphatic selenenyl sulfide such as Cys-S-Se-Cys. We find that local chemical environments of mercury and selenium do not change upon digestion of the fish with simulated gastric fluid. We discuss the toxicological implications for humans consuming fish.

  10. Chemical Forms of Mercury And Selenium in Fish Following Digestion With Simulated Gastric Fluid

    SciTech Connect

    George, G.N.; Singh, S.P.; Prince, R.C.; Pickering, I.J.

    2009-05-18

    Fish is a major dietary source of potentially neurotoxic methylmercury compounds for humans. It is also a rich source of essential selenium. We have used in situ mercury L{sub III}-edge and selenium K-edge X-ray absorption spectroscopy to chemically characterize the methylmercury and selenium in both fresh fish and fish digested with simulated gastric fluid. For the mercury, we confirm our earlier finding [Harris et al. (2003) Science301, 1203] that the methylmercury is coordinated by a single thiolate donor, which resembles cysteine, and for the selenium, we find a mixture of organic forms that resemble selenomethionine and an aliphatic selenenyl sulfide such as Cys-S-Se-Cys. We find that local chemical environments of mercury and selenium do not change upon digestion of the fish with simulated gastric fluid. We discuss the toxicological implications for humans consuming fish.

  11. Influence of whey protein-beet pectin conjugate on the properties and digestibility of β-carotene emulsion during in vitro digestion.

    PubMed

    Xu, Duoxia; Yuan, Fang; Gao, Yanxiang; Panya, Atikorn; McClements, David Julian; Decker, Eric Andrew

    2014-08-01

    The impact of a whey protein isolate (WPI)-beet pectin (BP) conjugate (formed by dry-heating) on the physical properties and digestibilities of β-carotene and carrier oil in oil-in-water emulsions was studied when they passed through a model gastrointestinal system. β-Carotene emulsions were stabilized by WPI, unconjugated and conjugated WPI-BP, separately. The emulsions were then passed through an in vitro digestion model and the mean droplet size, droplet distribution, zeta-potential, free fatty acids and β-carotene released were measured. The stability to droplet flocculation and coalescence during digestion was increased for the WPI-BP conjugate stabilized emulsion. Addition of BP onto the WPI stabilized emulsions could inhibit the releases of carrier oil (MCT) and β-carotene. The releases of free fatty acids and β-carotene did not differ greatly between the unconjugated and conjugated WPI-BP stabilized emulsions. These results have important implications for protein-polysaccharide stabilized emulsions and conjugates used for the protection and delivery of bioactive compounds.

  12. Improving Project Outcomes and Growing the Anaerobic Digestion Industy Report

    EPA Pesticide Factsheets

    Anaerobic digestion ombudsmen assist with project development, ensure the long-term sustainability of projects, and help advance the industry. This report explores the benefits of anaerobic digestion ombudsmen and provides guidance for implementing them.

  13. Rapid determination of total Kjeldahl nitrogen using microwave digestion.

    PubMed

    Lo, K V; Wong, W T; Liao, P H

    2005-01-01

    A closed-vessel microwave digestion process for the determination of total Kjeldahl nitrogen (TKN) has been developed for sewage and wastewater. TKN values obtained from the microwave digestion method were in excellent agreement with those of the thermal digestion method. The accuracy of both analytical methods is comparable. In comparison to the conventional thermal digestion, the microwave method shortened the time required for complete digestion from 4 h to 25 min, and also decreased the maximum digestion temperature from 380 degrees C to 200 degrees C. This developed method may contribute to a significant reduction in sample digestion time, resulting in an increase in analytical throughput. The microwave digestion method developed in this study could be a rapid and efficient means for TKN determination for sewage wastewater and sludge.

  14. Digestion of Nucleic Acids Starts in the Stomach

    PubMed Central

    Liu, Yu; Zhang, Yanfang; Dong, Ping; An, Ran; Xue, Changhu; Ge, Yinlin; Wei, Liangzhou; Liang, Xingguo

    2015-01-01

    The ingestion of nucleic acids (NAs) as a nutritional supplement or in genetically modified food has attracted the attention of researchers in recent years. Discussions over the fate of NAs led us to study their digestion in the stomach. Interestingly, we found that NAs are digested efficiently by human gastric juice. By performing digests with commercial, recombinant and mutant pepsin, a protein-specific enzyme, we learned that the digestion of NAs could be attributed to pepsin rather than to the acidity of the stomach. Further study showed that pepsin cleaved NAs in a moderately site-specific manner to yield 3′-phosphorylated fragments and the active site to digest NAs is probably the same as that used to digest protein. Our results rectify the misunderstandings that the digestion of NAs in the gastric tract begins in the intestine and that pepsin can only digest protein, shedding new light on NA metabolism and pepsin enzymology. PMID:26168909

  15. Diversity Digest. Volume 9, Number 2

    ERIC Educational Resources Information Center

    Musil, Caryn McTighe, Ed.; Hovland, Kevin, Ed.

    2005-01-01

    Published by the Association of American Colleges and Universities, this issue of "Diversity Digest" focuses on institutional leadership and how it advances diversity in higher education. Articles presented in this issue include: (1) Intercultural Learning for Inclusive Excellence (Edgar Beckham); (2) Demanding, Attracting, and Developing…

  16. Diversity Digest. Volume 9, Number 1

    ERIC Educational Resources Information Center

    Musil, Caryn McTighe, Ed.; Hovland, Kevin, Ed.

    2005-01-01

    Civic engagement is the focus of this issue of "Diversity Digest." Concrete examples of institutions that have linked diversity and civic engagement in powerful, effective, and educationally transforming ways are presented. What is seen in the field is encouraging. Articles feature new conceptual frameworks for civic learning, curricular…

  17. What Is Down Syndrome? 1984 Digest.

    ERIC Educational Resources Information Center

    Ferrara, Dianne

    The digest presents an overview on Down Syndrome. The history of the term is traced to its association with Dr. John Langdon Down who first described the condition in 1866. Characteristics of Down Syndrome are noted, including mental retardation, short stature, epicanthic folds, reduced muscle tone, joint hyperflexibility, and premature aging.…

  18. Student Dress Policies. ERIC Digest, Number 117.

    ERIC Educational Resources Information Center

    Isaacson, Lynne

    Educators and the public are divided over the value of implementing school-uniform policies in the public schools. This digest examines arguments for and against school-uniform policies, identifies legal considerations, and offers guidelines for implementing policies on student dress. Most parents have responded favorably to uniform policies,…

  19. Stress in the Work Place: ERIC Digest.

    ERIC Educational Resources Information Center

    Long, Bonita C.

    Although employment can be an exciting challenge, it can also induce stress. This digest examines some of the characteristics of job-related stress. Three concepts characterize the association of work, mental health, and physical health. (1) Stress is an interaction between individuals and any source of environmental demand. (2) A stressor is an…

  20. Reducing Error in Mail Surveys. ERIC Digest.

    ERIC Educational Resources Information Center

    Cui, Weiwei

    This Digest describes four types of errors in mail surveys and summarizes the ways they can be reduced. Any one of these sources of error can make survey results unacceptable. Sampling error is examined through inferential statistics applied to sample survey results. In general, increasing sample size will decrease sampling error when simple…

  1. Classroom Questions. ERIC/AE Digest.

    ERIC Educational Resources Information Center

    Brualdi, Amy C.

    Questioning is one of the most popular modes of teaching, but it has the capacity to turn a child off to learning if done incorrectly. This digest provides teachers with information on the types of questions and questioning behaviors that can facilitate the learning process and on the types of questions that are ineffective. Good questions foster…

  2. Biotechnology Education and the Internet. ERIC Digest.

    ERIC Educational Resources Information Center

    Lee, Thomas

    The world of modern biotechnology is based on recent developments in molecular biology, especially those in genetic engineering. Since this is a relatively new and rapidly advancing field of study, there are few traditional sources of information and activities. This digest highlights biotechnology resources including those that can be found on…

  3. Multiple Intelligences: Gardner's Theory. ERIC Digest.

    ERIC Educational Resources Information Center

    Brualdi, Amy C.

    This digest discusses the origins of Howard Gardner's Theory of Multiple Intelligences, his definition of intelligence, the incorporation of the theory into the classroom, and its role in alternative assessment practices. Gardner defines intelligence as the "capacity to solve problems or to fashion products that are valued in one or more…

  4. Student Truancy. ERIC Digest, Number 125.

    ERIC Educational Resources Information Center

    DeKalb, Jay

    This Digest examines some of the ways that truancy affects both individuals and society. It identifies factors that may place students at greater risk of becoming truant and lists some consequences of nonattendance, including delayed promotion and graduation, lowered self-esteem, and lessened employment potential. The causes of truancy vary among…

  5. Recommended Competencies for Outdoor Educators. ERIC Digest.

    ERIC Educational Resources Information Center

    Richardson, Michelle; Simmons, Deborah

    This digest provides a framework for professional development of outdoor educators. Outdoor and environmental educators share similar principles of outdoor learning. Thus, the performance standards recently drafted by the North American Association for Environmental Education (NAAEE) can serve as a useful guide for outdoor education generally.…

  6. Teaching the Declaration of Independence. ERIC Digest.

    ERIC Educational Resources Information Center

    Patrick, John J.

    The Declaration of Independence is the founding document of the United States. It is part of the social studies core curriculum in U.S. schools. By the time they graduate from high school, students are expected to know the main ideas in the Declaration of Independence and their significance. This digest discusses: (1) the origins of the…

  7. Effective Teaching in Distance Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Mielke, Dan

    Distance education is an alternative method for delivering academic course work to students unable to attend traditional campus-based classes. This Digest presents information on the many forms of distance education and keys to successful teaching with distance education. Distance education is a method of education in which the learner is…

  8. Involving Migrant Families in Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Martinez, Yolanda G.; Velazquez, Jose A.

    This digest describes parent involvement in their children's education from the perspective of migrant parents and educators and offers strategies to enhance the experience of schooling for migrant students and their families. Teachers often perceive parent involvement as preparing children for school, attending school events, and fulfilling…

  9. Locating Job Information. ERIC Digest No. 85.

    ERIC Educational Resources Information Center

    Wagner, Judith O.

    How to locate information that can be used in career decision making is the subject of this digest. The first section lists the career/occupational information collections generally found in public libraries, including printed resources, information about associations, information about local sources of job information, information on specific…

  10. Acquiring and Managing Electronic Journals. ERIC Digest.

    ERIC Educational Resources Information Center

    Curtis, Donnelyn; Yue, Paoshan

    Electronic journals are both a blessing and a curse for libraries. To be meaningful in the current information environment--to meet users' ever-increasing demands--libraries must acquire as many appropriate full text resources as possible, as quickly as possible, and make them easy to use. This Digest provides tips for acquiring and providing…

  11. FOI Digest Index, 1970-1979.

    ERIC Educational Resources Information Center

    Freedom of Information Center, Columbia, MO.

    An index of the reports and articles appearing in the 1970-79 issues of the "Freedom of Information Digest," a bimonthly newsletter, presents the titles in more than 100 subject categories. The topics covered by the index include access laws, general/school censorship, access to records, employee records, executive privilege, financial disclosure,…

  12. Guidelines for Family Television Viewing. ERIC Digest.

    ERIC Educational Resources Information Center

    ERIC Clearinghouse on Elementary and Early Childhood Education, Urbana, IL.

    This ERIC digest addresses problems associated with children's excessive viewing of television programs and commercials and provides suggestions to help parents guide their children's television viewing. Children who watch television 3 to 5 hours a day have little time for other activities such as play, reading, and talking with others. Excessive…

  13. Nutrition Programs for Children. ERIC Digest.

    ERIC Educational Resources Information Center

    ERIC Clearinghouse on Elementary and Early Childhood Education, Urbana, IL.

    Despite recognition of the importance of good nutrition for children's cognitive development, many children in America are poorly nourished. This digest reviews programs designed to address this problem and suggests ways to improve child nutrition and school meal programs. Federal programs administered by the Food and Nutrition Service of the…

  14. Indicators of normal carbohydrate digestion in children

    Technology Transfer Automated Retrieval System (TEKTRAN)

    More research is needed to determine the nutritional and clinical significance of the intermediate values of low but not deficient duodenal disaccharidase activities, but the Dahlqvist-method biopsy assay of activity serves as a gnomon of carbohydrate digestion, in the sense that Anaximander used a ...

  15. Item Banking. ERIC/AE Digest.

    ERIC Educational Resources Information Center

    Rudner, Lawrence

    This digest discusses the advantages and disadvantages of using item banks, and it provides useful information for those who are considering implementing an item banking project in their school districts. The primary advantage of item banking is in test development. Using an item response theory method, such as the Rasch model, items from multiple…

  16. Cable Television in the Classroom. ERIC Digest.

    ERIC Educational Resources Information Center

    Holmes, Glen A.; Branch, Robert C.

    Using cable television in the classroom allows teachers to include the latest news and current events in class discussions. However, many educational practitioners are uninformed about the concept and lack the knowledge to implement the technology in the classroom. This digest describes how cable television can be integrated into elementary and…

  17. Counselor Intentionality and Effective Helping. ERIC Digest.

    ERIC Educational Resources Information Center

    Schmidt, John J.

    This digest on counselor intentionality notes that the counseling profession has historically searched for characteristics and behaviors that contribute to successful helping relationships. It identifies one such characteristic, the counselor's level and degree of intentionality, as relating to the notion that successful counselors select their…

  18. [Analysis of hepato-digestive oncology practices].

    PubMed

    Guillemot, Florence; Cornu, Chloé; Marterer, Justine; Thegarid, Héléne

    2014-09-01

    Help nursing students and new professionals to understand the different facets of care is at the heart of the managerial and pedagogical process coordinated by the health framework. The formalisation and use of learning situations promote the identification of opportunities for learning, modelling and the assessment of practices. Feedback from the hepato-digestive oncology service.

  19. Forces Motivating Institutional Reform. ERIC Digest.

    ERIC Educational Resources Information Center

    Yee, Jennifer Agnes

    This digest provides an overview of forces, both internal and external, driving change on community college campuses. External agents of change are: (1) societal needs and expectations, which are shifting toward multicultural diversity; (2) international competition, requiring that workers be highly skilled in adapting to international cultures;…

  20. Lasting Benefits of Preschool Programs. ERIC Digest.

    ERIC Educational Resources Information Center

    Schweinhart, Lawrence J.

    This digest reviews various longitudinal studies that examined the long-term effects of programs that served young children living in poverty and at risk of school failure. Concerning program effects on school performance, all studies that collected data on children's intellectual performance found that their program groups had better intellectual…

  1. National Standards for Athletic Coaches. ERIC Digest.

    ERIC Educational Resources Information Center

    Brylinsky, Jody

    This digest asserts that the question of coach preparation and training has become a priority issue for many schools and communities, though the research is limited. It examines reasons to have coach education; the scope of sport participation; the status of coach education and training in the United States; National standards for coach education;…

  2. Outdoor Experiences for Young Children. ERIC Digest.

    ERIC Educational Resources Information Center

    Rivkin, Mary S.

    This digest examines the value of outdoor experience for young children, reasons for its decline, ways to enhance school play spaces, and aspects of developmentally appropriate outdoor environments. Young children appear to benefit from being outdoors and especially need the broad experiential base provided by being outdoors. The richness and…

  3. Children's Nutrition and Learning. ERIC Digest.

    ERIC Educational Resources Information Center

    ERIC Clearinghouse on Elementary and Early Childhood Education, Urbana, IL.

    This digest reviews research on the link between children's nutrition and their ability to learn from the prenatal through school years. It also discusses the importance of nutrition education for children. The need for adequate nutrition during pregnancy and the preschool years is highlighted by research that indicates that low birthweight…

  4. Diversity Digest. Volume 9, Number 3

    ERIC Educational Resources Information Center

    Musil, Caryn McTighe, Ed.; Hovland, Kevin, Ed.

    2006-01-01

    This issue of "Diversity Digest" grows out of one recent effort to raise the visibility of science in diversity and global learning initiatives. Articles in this issue include: (1) Science, Diversity, and Global Learning: Untangling Complex Problems (Kevin Hovland); (2) Breaking the Pyramid: Putting Science in the Core (Darcy Kelley);…

  5. Deammonification reaction in digested swine effluents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Farmers that would like to implement biological nitrogen (N) removal from the effluent of anaerobic digesters (AD) – for example to comply with regional surplus nitrogen regulations or to take advantage of environmental nutrient credit programs – are often limited by the low amount of endogenous ca...

  6. Liderazgo etico (Ethical Leadership). ERIC Digest.

    ERIC Educational Resources Information Center

    Lashway, Larry

    Until very recently, ethical issues were given little attention in administrator-preparation programs. This digest in Spanish outlines the ethical responsibilities of school leaders and the dilemmas that they face. It offers the following suggestions for resolving ethical dilemmas: (1) Leaders should have and be willing to act on a definite sense…

  7. Liderazgo visionario (Visionary Leadership). ERIC Digest.

    ERIC Educational Resources Information Center

    Lashway, Larry

    "Vision" is one of the most frequently used buzzwords in the education literature of the 1990s. This digest in Spanish presents an overview of visionary leadership, which many education experts consider to be a make-or-break task for the school leader. It discusses various definitions of vision, the significance of vision for…

  8. USSR Space Life Sciences Digest, Issue 26

    NASA Technical Reports Server (NTRS)

    Stone, Lydia Razran (Editor); Frey, Mary Ann (Editor); Teeter, Ronald (Editor); Garshnek, Victoria (Editor); Rowe, Joseph (Editor)

    1990-01-01

    This is the twenty-sixth issue of NASA's USSR Space Life Sciences Digest. It contains abstracts of 35 journal papers or book chapters published in Russian and of 8 Soviet books. In addition, the proceedings of an Intercosmos conference on space biology and medicine are summarized.

  9. Grade Inflation in Higher Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Young, Carol

    Grade inflation has commanded increasing attention in the academic world in recent years, with administrators, faculty, and academic analysts unable to agree on whether grade inflation actually exists or is a myth to be debunked. This Digest reviews research in support of and against the existence of grade inflation. A statistical analysis report…

  10. Teaching the Bill of Rights. ERIC Digest.

    ERIC Educational Resources Information Center

    Patrick, John J.

    This ERIC Digest on teaching about the Bill of Rights in the schools examines the status, the deficiencies, and means to improve citizenship education. Currently, the Bill of Rights is taught at least four times during the elementary and secondary grades. Constitutional rights and liberties are stressed in K-12 curriculum goals for social studies…

  11. Mediation in the Schools. ERIC Digest.

    ERIC Educational Resources Information Center

    Trevaskis, David Keller

    This digest discusses mediation as a form of conflict management that is receiving widespread attention in schools. Mediation involves a neutral third person, called a mediator, who assists the disputants in resolving their problem with the consent of all parties. It offers a risk-free way to settle disputes for the parties involved. Unresolved…

  12. The Debate over Spanking. ERIC Digest.

    ERIC Educational Resources Information Center

    Ramsburg, Dawn

    This digest explores some of the reasons for spanking, examines its effectiveness, and suggests alternative discipline methods. Many parents believe that spanking will teach children not to do things that are forbidden, stop them quickly when they are being irritating, and encourage them to do what they should. Others believe nonphysical forms of…

  13. Advertising in the Schools. ERIC Digest.

    ERIC Educational Resources Information Center

    Aidman, Amy

    This digest reviews the recent history of advertising to children, spotlights controversial marketing efforts, and examines the nature of commercial messages directed toward children in public schools. Because of the increase in children's spending power in recent decades, advertisers have closely targeted children as consumers. Advertising…

  14. Girls and Violence. ERIC Digest Number 143.

    ERIC Educational Resources Information Center

    Weiler, Jeanne

    This digest reviews current research on girls' delinquent and violent behavior, the factors contributing to it, and effective programming strategies to prevent it. Girls are more involved in violent crime than they were a decade ago. Their murder rate is up 64%, although status offenses (offenses only because the perpetrator is a minor) continue…

  15. Home Schooling. ERIC Digest, Number 95.

    ERIC Educational Resources Information Center

    Lines, Patricia M.

    A small but increasing number of school-aged children are engaging in home schooling--pursuing learning at home or elsewhere in the community. This digest summarizes research findings on and issues around home schooling. It describes the historical roots of home schooling, the estimated number of participants, the constitutionality and legal…

  16. Digest of Educational Statistics, 1969 Edition.

    ERIC Educational Resources Information Center

    Simon, Kenneth A.; Grant, W. Vance

    The 1969 edition of the Digest of Educational Statistics is the eighth in this series of annual publications. The primary purpose of this compendium of tables is to provide an abstract of statistical information covering the broad field of American education from kindergarten through the graduate school. Subjects on which statistics are given…

  17. Therapeutic Uses of Outdoor Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Berman, Dene S.; Davis-Berman, Jennifer

    This digest examines the positive effects on emotional well-being of several types of outdoor education programs. Although many outdoor education and experiential programs enhance emotional growth, such "therapeutic" outcomes may be considered incidental to program goals. In contrast, programs aimed primarily at "therapy"…

  18. Migrant Farmworkers and Their Children. ERIC Digest.

    ERIC Educational Resources Information Center

    Martin, Philip

    This digest reviews the population characteristics of migrant and seasonal farmworkers and their children. Since the 1960s, federal programs for migrant workers and their families have multiplied. However, these programs have differing definitions for "migrant and seasonal farmworker," and no current data system provides a reliable count…

  19. Financing Preschool for All Children. ERIC Digest.

    ERIC Educational Resources Information Center

    Svestka, Sherlie S.

    This digest compares the efforts of the United States and of other member countries of the Organization for Economic Co-operation and Development (OECD) to finance center- and facility-based preschool. In many OECD countries, public preschool is more widely available than in the United States. For example, in France, 100%, and in Italy,…

  20. Presidents and Trustees in Partnership. ERIC Digest.

    ERIC Educational Resources Information Center

    Iwanaga, John

    This digest discusses the relationship between community college trustees and the president, focusing on the necessity of establishing a rapport before times of crises. It is vital that the roles of both parties be clearly defined, and that each has a mutual responsibility to inform the other in an emergency. The president should embody the…

  1. Dairy cow manure digester and cogenerator performance

    SciTech Connect

    Pigg, D.L.; Vetter, R.L.

    1985-01-01

    A 94 m/sup 3/ mesophilic digester with a 15 kW engine-generator was monitored. The average manure collected was 6.48 kg VS/cow/day. An ultimate methane yield (Bo) of 0.25 L CH4/g VS was calculated. The potential gross energy production was determined to be 3 kWh/cow/day.

  2. Diversity Digest. Volume 8, Number 1

    ERIC Educational Resources Information Center

    Giles, Mark, Ed.

    2004-01-01

    Sponsored by the Pathways to College Network, this issue of "Diversity Digest" highlights some of the research that informs Pathways. Several of the articles identify factors that affect underserved students' ability to attend and succeed at postsecondary institutions. In the first article, "The Right to Learn and the Pathways to College Network"…

  3. Issues in Media Ethics. ERIC Digest.

    ERIC Educational Resources Information Center

    Aiex, Nola Kortner; Gottlieb, Stephen S.

    Noting that over the past decade incidents have occurred and new technologies have appeared which together have raised questions about the ethical values of American journalists, this Digest seeks to identify some of those ethical issues and to point to the work of those who have studied these issues. It addresses issues of plagiarism and…

  4. Anaerobic Digestion in a Flooded Densified Leachbed

    NASA Technical Reports Server (NTRS)

    Chynoweth, David P.; Teixeira, Arthur A.; Owens, John M.; Haley, Patrick J.

    2009-01-01

    A document discusses the adaptation of a patented biomass-digesting process, denoted sequential batch anaerobic composting (SEBAC), to recycling of wastes aboard a spacecraft. In SEBAC, high-solids-content biomass wastes are converted into methane, carbon dioxide, and compost.

  5. A Science Fair Companion. ERIC Digest.

    ERIC Educational Resources Information Center

    McCann, Wendy Sherman

    This digest comments on various aspects of school science fairs. General expectations for science fair projects and participants are discussed, and tips for choosing a topic and completing a project are given. Organizational strategies for teachers charged with conducting science fairs are presented. Guidelines for parents in helping children with…

  6. Portfolio Development for Teacher Candidates. ERIC Digest.

    ERIC Educational Resources Information Center

    Takona, James P.

    This Digest is intended to help teacher candidates systematically gauge their progress toward the teaching profession by developing a portfolio. Portfolios are one way to assess teacher candidates, and they are a major requirement for experienced teachers seeking board certification from the National Board for Professional Teaching Standards. The…

  7. Science Fairs in Elementary School. ERIC Digest.

    ERIC Educational Resources Information Center

    Balas, Andrea K.

    This digest presents a summary discussion of the value of holding science fairs in the elementary school context. Reasons for conducting science fairs for elementary students are discussed in terms of several learning theories. Developmentally appropriate types of elementary science projects are suggested. Goals for elementary school science fairs…

  8. Knowledge Management in Instructional Design. ERIC Digest.

    ERIC Educational Resources Information Center

    Spector, J. Michael; Edmonds, Gerald S.

    This digest reviews what instructional designers do, describes knowledge management, and indicates how knowledge management is influencing instructional design. The first section defines instructional design (ID) and briefly describes the ID process. The second section covers knowledge management (KM), including definitions of KM and systems,…

  9. The Argument for Early Intervention. 1984 Digest.

    ERIC Educational Resources Information Center

    Smith, Barbara J.; Strain, Phillip S.

    The digest presents the background and reasons for early intervention with children at risk for handicaps. Early intervention is defined, and three primary reasons for intervention are cited: (1) to enhance the child's development, (2) to provide support and assistance to the family, and (3) to maximize the child's and family's benefit to society.…

  10. Format Proliferation in Public Libraries. ERIC Digest.

    ERIC Educational Resources Information Center

    Parry, Norm

    More choice in formats for library customers may mean more constraints on choices in materials acquisition. An increase in the number of formats libraries provide may, over time, substantially alter the quality and diversity of library collections. This ERIC Digest examines some of the costs and challenges presented by format proliferation and…

  11. Economics of Information in Education. ERIC Digest.

    ERIC Educational Resources Information Center

    Farid, Mona

    This digest on the economics of information in education argues that the production, organization, analysis, evaluation, and dissemination of information in education constitute major economic activities, with associated costs and benefits. The document comprises sections on: the value of information; information as an "economic good";…

  12. Science and Equity Digest, January 2000.

    ERIC Educational Resources Information Center

    Education Development Center, Inc., Newton, MA. Women's Educational Equity Act Dissemination Center.

    This digest presents information on the state of sex equity in the fields of science and engineering. Featured articles include: "Becoming a Scientist" (Shirley Malcolm); "Gender Equity Issues in Science Careers" (Sue V. Rosser and Julie Montgomery); and "Innovations in Intervention Settings" (Katherine Darke and Beatriz Chu Clewell). A list of…

  13. Accessing ERIC with Your Microcomputer. ERIC Digest.

    ERIC Educational Resources Information Center

    Klausmeier, Jane A.

    Focusing on how to use a microcomputer as a terminal for searching online databases, this digest addresses the following topics: (1) hardware and software requirements; (2) configuring the software; and (3) basic requirements for specific microcomputers. Special features in communications software which allow microcomputer users to do database…

  14. Early Childhood Violence Prevention. ERIC Digest.

    ERIC Educational Resources Information Center

    Massey, Marilyn S.

    Noting that all Americans are stakeholders in the quest to prevent violence in the critical early years, this Digest focuses on preventing violence in children's lives and suggests ways caregivers, parents, and teachers can reduce the damaging effects of violence. Even before a child is born, violence can have a profound effect upon its life.…

  15. Egg white ovalbumin digestion mimicking physiological conditions.

    PubMed

    Martos, Gustavo; Contreras, Patricia; Molina, Elena; López-Fandiño, Rosina

    2010-05-12

    Gastrointestinal digestion of ovalbumin (OVA) was simulated using an in vitro system in two steps, which mimicked digestion in the stomach and duodenum, to assess the effect of different gastric pHs, different concentrations of proteases, and the presence of surfactants, such as phosphatidylcholine (PC) and bile salts (BS). OVA was very resistant to pepsin action at an enzyme/substrate ratio that would resemble a physiological situation (1:20 w/w, 172 units/mg) at pH values equal or above 2. The presence of PC did not change the susceptibility of OVA to proteolysis with pepsin. Fluorescence experiments showed that OVA interacted with PC vesicles, particularly at acidic pH, but it is likely that the protein maintained a high degree of conformational stability, resisting pepsin action. The presence of BS at physiological concentrations considerably increased the proteolysis of OVA by a mixture of pancreatic enzymes. The addition of PC made OVA even more sensitive to proteolytic degradation, suggesting that OVA could associate with the surfactants under duodenal conditions, increasing its exposure to pancreatic proteinases. Immunoreactivity against IgE from sera of allergic patients was retained after in vitro gastric digestion, depending on the reactivity of the sera, but it decreased considerably after in vitro duodenal digestion.

  16. Internet Basics: Update 1996. ERIC Digest.

    ERIC Educational Resources Information Center

    Tennant, Roy

    This update to a previous digest briefly describes the Internet computer network, the physical connections and communication protocols that make it possible, and the applications and information resources the network provides. The applications covered include electronic mail and listservs, the world wide web, telnet connections with remote library…

  17. Libraries and the Internet. ERIC Digest.

    ERIC Educational Resources Information Center

    McKenna, Mary

    The Internet is an international computer network encompassing thousands of smaller interconnected networks. This digest describes various uses of the Internet and its impact on libraries, as well as Internet-related library issues. The Internet applications of electronic mail (E-mail), telnet, and file transfer protocol (FTP) are briefly…

  18. Learning History through Children's Literature. ERIC Digest.

    ERIC Educational Resources Information Center

    Nelson, Lynn R.; Nelson, Trudy A.

    Teaching history using children's literature, both fiction and non-fiction, is an old idea enjoying new vitality in the elementary and middle school curriculum. This digest discusses: (1) the revival of interest in teaching history through children's literature; (2) research-based guidelines for teachers of history and children's literature, and…

  19. Marketing Career Counseling Services: ERIC Digest.

    ERIC Educational Resources Information Center

    Hopkins, Sareena

    At a time when career counseling services are increasingly essential, they remain marginalized and under-used. This digest explores ways in which marketing counseling services in Canada can strengthen the professional identity of career counselors and increase public acceptance of this field. Many career counselors feel that marketing corrodes…

  20. Outdoor Education and Environmental Responsibility. ERIC Digest.

    ERIC Educational Resources Information Center

    Yerkes, Rita; Haras, Kathy

    Outdoor education programs provide opportunities for students to become environmentally conscious citizens. However, awareness of environmental issues is not enough to preserve our world of limited natural resources. Students must also recognize their environmental responsibilities and change their behaviors accordingly. This digest reviews the…

  1. Language Learning Strategies: An Update. ERIC Digest.

    ERIC Educational Resources Information Center

    Oxford, Rebecca

    This digest discusses second language learning strategies--specific actions, behaviors, steps, or techniques students used to improve their progress in apprehending, internalizing, and using the second language. The first section discusses characteristics of good language learners. The second section highlights research findings that suggest…

  2. The Gifted and Talented Handicapped. 1985 Digest.

    ERIC Educational Resources Information Center

    Maker, C. June; Grossi, John

    The digest examines aspects of serving gifted and talented handicapped students in the schools. This population includes persons of outstanding ability or potential who are capable of high performance despite handicaps such as visual, hearing or orthopedic impairments; emotional disturbances; or learning disabilities. Examples of prominent gifted…

  3. Assessing the Development of Preschoolers. ERIC Digest.

    ERIC Educational Resources Information Center

    Katz, Lilian G.

    To help parents address those aspects of their child's development which may need special encouragement, support, or intervention, this digest delineates 11 categories of behavior for assessment. Parents should not be alarmed if their children are having difficulty in only a few categories, and they should not judge their children's permanent…

  4. Child Labor in Agriculture. ERIC Digest.

    ERIC Educational Resources Information Center

    Davis, Shelley

    An estimated 200,000-800,000 children and adolescents work in the United States as migrant agricultural laborers, either alone or with their families. This digest describes the statutory and economic factors contributing to the presence of children in the fields and the impact of this labor on their health and educational progress. The Fair Labor…

  5. Understanding and Preventing Teacher Burnout. ERIC Digest.

    ERIC Educational Resources Information Center

    Wood, Teri; McCarthy, Chris

    This digest explains that burnout results from the chronic perception that one is unable to cope with daily life demands. Teachers must face classrooms full of students every day; negotiate potentially stressful interactions with parents, administrators, counselors, and other teachers; contend with relatively low pay and shrinking school budgets;…

  6. Outdoor Education and Troubled Youth. ERIC Digest.

    ERIC Educational Resources Information Center

    Berman, Dene S.; Davis-Berman, Jennifer

    This digest briefly summarizes the parallel development of outdoor education and outdoor therapeutic programs for troubled and adjudicated youth, describes the rationale supporting outdoor approaches, and reports related research and evaluation findings. First attempts to use the outdoors as a healing environment were "tent therapy"…

  7. The Precipitation Behavior of Poorly Water-Soluble Drugs with an Emphasis on the Digestion of Lipid Based Formulations.

    PubMed

    Khan, Jamal; Rades, Thomas; Boyd, Ben

    2016-03-01

    An increasing number of newly discovered drugs are poorly water-soluble and the use of natural and synthetic lipids to improve the oral bioavailability of these drugs by utilizing the digestion pathway in-vivo has proved an effective formulation strategy. The mechanisms responsible for lipid digestion and drug solubilisation during gastrointestinal transit have been explored in detail, but the implications of drug precipitation beyond the potential adverse effect on bioavailability have received attention only in recent years. Specifically, these implications are that different solid forms of drug on precipitation may affect the total amount of drug absorbed in-vivo through their different physico-chemical properties, and the possibility that the dynamic environment of the small intestine may afford re-dissolution of precipitated drug if present in a high-energy form. This review describes the events that lead to drug precipitation during the dispersion and digestion of lipid based formulations, common methods used to inhibit precipitation, as well as conventional and newly emerging characterization techniques for studying the solid state form of the precipitated drug. Moreover, selected case studies are discussed where drug precipitation has ensued from the digestion of lipid based formulations, as well as the apparent link between drug ionisability and altered solid forms on precipitation, culminating in a discussion about the importance of the solid form on precipitation with relevance to the total drug absorbed.

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

    PubMed Central

    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. PMID:28293487

  9. Child Care Quality: An Overview for Parents. ERIC Digest.

    ERIC Educational Resources Information Center

    Patten, Peggy; Ricks, Omar Benton

    Many parents want to know how important the quality of care is to children's social, emotional, and academic development. This digest synthesizes some major recent research on child care quality. First, the digest explains what features contribute to quality of care. The digest also explains the differences between studies of how quality is…

  10. Communication Apprehension: The Quiet Student in Your Classroom. ERIC Digest.

    ERIC Educational Resources Information Center

    Holbrook, Hilary Taylor

    Noting that communication apprehension (CA) is a pattern of anxiety that can profoundly affect oral communication, social skills, and self-esteem, this digest examines some causes and consequences of CA and ways in which it can be diminished. Following an introduction, the digest defines CA and some of its characteristics. Next, the digest looks…

  11. Blending anaerobic co-digestates: synergism and economics.

    PubMed

    Navaneethan, N; Topczewski, P; Royer, S; Zitomer, D

    2011-01-01

    Co-digestion is the process in which wastes from various sources are treated together. Therefore, more organic carbon is added to make efficient use of existing digesters. The objectives of this study were to compare potential co-digestates, determine synergistic and antagonistic co-digestion outcomes and estimate economic benefits for preliminary screening. Over 80 wastes were identified from 54 facilities within 160 km of an existing municipal digester. Synergistic, antagonistic and neutral co-digestion outcomes were observed for the various wastes. A simple economic comparison resulted in the greatest potential benefits for four co-digestates: yeast flavorings production waste, meat production dissolved air flotation float, acid whey from cheese production and thin stillage from corn ethanol production. Performance was investigated using bench-scale digesters receiving primary sludge with and without co-digestates. Methane production rates were 105 and 66% higher when co-digestates were present, but were anticipated to increase only 57 and 23% due to the additional chemical oxygen demand. Therefore, significant synergistic outcomes were observed during co-digestion. Co-digestion of the most promising wastes with primary sludge in full scale was estimated to generate enough electricity to power more than 2,500 houses.

  12. Inactivation of dairy manure-borne pathogens by anaerobic digestion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Anaerobic digestion of animal manure has the potential to inactivate enteric pathogens, thereby reducing exposures to livestock and humans when the products of digestion are disposed by land-spreading or irrigation or returned to livestock uses such as bedding. Data on digester effectiv...

  13. Nanostructured microfluidic digestion system for rapid high-performance proteolysis.

    PubMed

    Cheng, Gong; Hao, Si-Jie; Yu, Xu; Zheng, Si-Yang

    2015-02-07

    A novel microfluidic protein digestion system with a nanostructured and bioactive inner surface was constructed by an easy biomimetic self-assembly strategy for rapid and effective proteolysis in 2 minutes, which is faster than the conventional overnight digestion methods. It is expected that this work would contribute to rapid online digestion in future high-throughput proteomics.

  14. Effect of initial protein concentration and pH on in vitro gastric digestion of heated whey proteins.

    PubMed

    Zhang, Sha; Vardhanabhuti, Bongkosh

    2014-02-15

    The in vitro digestion of heated whey protein aggregates having different structure and physicochemical properties was evaluated under simulated gastric conditions. Aggregates were formed by heating whey protein isolates (WPI) at 3-9% w/w initial protein concentration and pH 3.0-7.0. Results showed that high protein concentration led to formation of larger WPI aggregates with fewer remaining monomers. Aggregates formed at high protein concentrations showed slower degradation rate compared to those formed at low protein concentration. The effect of initial protein concentration on peptide release pattern was not apparent. Heating pH was a significant factor affecting digestion pattern. At pH above the isoelectric point, the majority of the proteins involved in the aggregation, and aggregates formed at pH 6.0 were more susceptible to pepsin digestion than at pH 7.0. At acidic conditions, only small amount of proteins was involved in the aggregation and heated aggregates were easily digested by pepsin, while the remaining unaggregated proteins were very resistant to gastric digestion. The potential physiological implication of these results on satiety was discussed.

  15. Birth of the Canadian Digestive Health Foundation.

    PubMed

    Beck, Ivan T

    2004-01-01

    The Canadian Digestive Disease Foundation, renamed the Canadian Digestive Health Foundation--Fondation canadienne pour la promotion de la santé digestive--in December 2001, is the culmination of ongoing efforts by the Canadian Association of Gastroenterology to establish an independent charitable organization. In February 2001, it was officially endorsed as the Foundation for the Canadian Association of Gastroenterology. The initial efforts to establish this Foundation, led by Dr Richard McKenna in 1963, were unsuccessful. In 1991, Glaxo Canada (now GlaxoSmithKline) became a founding donor, and with the four founding physicians--Drs Ivan T Beck, Richard H Hunt, Suzanne E Lemire and Alan BR Thomson--the expenses to establish the Foundation were met. A charitable number was obtained in 1995 (0997427-11). The second founding donor was Janssen Canada (now Janssen-Ortho), and public education support came from Astra Canada (now AstraZeneca Canada). The Foundation initially relied on corporate donors, but now approaches physicians, patients and the general public. The objectives of the Foundation are to advance the science of gastroenterology and to provide knowledge of digestive diseases and nutrition to the general public, to enhance the quality of life of persons who are afflicted with these disorders. The major achievements of the Foundation are the provision of one-year operating grants to new investigators, which have allowed them to accumulate early data and subsequently obtain support from other major granting organizations. It also provides Fellowships and studentship support grants, in conjunction with the Canadian Institutes of Health Research and the pharmaceutical industry. The education committee found that there was little research support in this field, considering the large economic burden of digestive disease and the amount of outstanding work done by Canadian researchers. A bilingual Web site, a web-based specialist's discussion program and bilingual

  16. Up-to-date modification of the anaerobic sludge digestion process introducing a separate sludge digestion mode.

    PubMed

    Sato, K; Ochi, S; Mizuochi, M

    2001-01-01

    Sewage treatment plants in Japan are subjected to advanced treatment to remove nutrients and hence control eutrophication problems in lakes and bays. This paper discusses the advantages and disadvantages of the separate digestion treatment mode for sludge generated from advanced wastewater treatment. In the separate digestion only primary sludge is digested and the excess activated sludge is directly dewatered. Separate digestion can reduce the return load of nutrients to approximately one third, and has major potential for the beneficial use of sludge.

  17. Impact of gastric pH profiles on the proteolytic digestion of mixed βlg-Xanthan biopolymer gels.

    PubMed

    Dekkers, B L; Kolodziejczyk, E; Acquistapace, S; Engmann, J; Wooster, T J

    2016-01-01

    The understanding of how foods are digested and metabolised is essential to enable the design/selection of foods as part of a balanced diet. Essential to this endeavour is the development of appropriate biorelevant in vitro digestion tools. In this work, the influence of gastric pH profile on the in vitro digestion of mixtures of β-lactoglobulin (βlg) and xanthan gum prior to and after heat induced gelation was investigated. A conventional highly acidic (pH 1.9) gastric pH profile was compared to two dynamic gastric pH profiles (initial pH of 6.0 vs. 5.2 and H(+) secretion rates of 60 vs. 36 mmol h(-1)) designed to mimic the changes in gastric pH observed during clinical trials with high protein meals. In moving away from the pH 1.9 model, to a pH profile reflecting in vivo conditions, the initial rate and degree of protein digestion halved during the first 45 minutes. After 90 minutes of gastric digestion, all three pH profiles caused similar extents of protein digestion. Given that 50% gastric emptying times of (test) meals are in range of 30-90 min, it would seem highly relevant to use a dynamic pH gastric model rather than a pH 1.9 (USP) or pH 3 model (INFOGEST) in assessing the impact of food structuring approaches on protein digestion. The impact that heat induced gelation had on the degree of gel digestion by pepsin was also investigated. Surprisingly, it was found that heat induced gelation of βlg-xanthan mixtures at 70-90 °C for 20 minutes lead to a considerable decrease in the rate of proteolysis, which contrasts many studies of dispersed aggregates and gels of βlg alone whose heating accelerates pepsin activity due to unfolding. In the present case, the formation of a dense protein network created a fine pore structure which restricted pepsin access into the gel thereby slowing proteolysis. This work not only has implications for the in vitro assessment of protein digestion, but also highlights how protein digestion might be slowed, learnings that

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

    PubMed

    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.

  19. Metal chemistry differences between digested and undigested sludges

    SciTech Connect

    Gibbs, R.J.; Angelidis, M.

    1988-01-01

    In a study of digested and undigested sludge chemical phases metal partitioning differences were found. The anaerobic digested sludges contained relatively more metals in the oxidizable phase but, in general, the chemical partitioning was similar for both the aerobic and anaerobic sludges. Conversely, the undigested sludge, although containing one-and-a-half times more organic carbon than the digested, did not contain a high metal concentration in the oxidizable phase as did the digested sludge. The microbial activity and physicochemical changes that occur during digestion were considered as the reasons for this difference.

  20. Selection of Bayer digestion technology and equipment for Chinese bauxite

    SciTech Connect

    Chaojian, M.; Xingjiu, T.; Runtian, L.; Xujun, Y.

    1996-10-01

    China is rich in bauxite with a proven reserve of more than two billion tons, which is almost the diaspore with complex and various minerals. To process this kind of ore the Bayer digestion is characterized by high temperature and high caustic concentration. Based on the behavior of silicon and titanium minerals digested in the lab and plant, the digestion technology and equipment for Chinese bauxite is discussed; and based on the Chinese construction condition, the economic comparison of several typical and industrial digestion equipment is estimated in the paper. As a conclusion, a proper digestion technology and equipment for Chinese bauxite is proposed.

  1. Recovery of indigenous enteroviruses from raw and digested sewage sludges.

    PubMed Central

    Goddard, M R; Bates, J; Butler, M

    1981-01-01

    We examined different types of raw sewage sludge treatment, including consolidation, anaerobic mesophilic digestion with subsequent consolidation, and aerobic-thermophilic digestion. Of these, the most efficient reduction in infectious virus titer was achieved by mesophilic digestion with subsequent consolidation, although a pilot-scale aerobic-thermophilic digester was extremely time effective, producing sludges with similarly low virus titers in a small fraction of the time. Although none of the treatments examined consistently produced a sludge with undetectable virus levels, mesophilic digestion alone was found to be particularly unreliable in reducing the levels of infectious virus present in the raw sludge. PMID:6274258

  2. Anaerobic digestion of lignocellulosic biomass: challenges and opportunities.

    PubMed

    Sawatdeenarunat, Chayanon; Surendra, K C; Takara, Devin; Oechsner, Hans; Khanal, Samir Kumar

    2015-02-01

    Anaerobic digestion (AD) of lignocellulosic biomass provides an excellent opportunity to convert abundant bioresources into renewable energy. Rumen microorganisms, in contrast to conventional microorganisms, are an effective inoculum for digesting lignocellulosic biomass due to their intrinsic ability to degrade substrate rich in cellulosic fiber. However, there are still several challenges that must be overcome for the efficient digestion of lignocellulosic biomass. Anaerobic biorefinery is an emerging concept that not only generates bioenergy, but also high-value biochemical/products from the same feedstock. This review paper highlights the current status of lignocellulosic biomass digestion and discusses its challenges. The paper also discusses the future research needs of lignocellulosic biomass digestion.

  3. Cantharidin decreases in vitro digestion of alfalfa and smooth bromegrass.

    PubMed

    Lenssen, A W; Blodgett, S L; Higgins, R A; Nagaraja, T G; Posler, G L; Broce, A B

    1990-10-01

    Blister beetles (Coleoptera:Meloidae) containing the toxin cantharidin can be incorporated with alfalfa (Medicago sativa L) during forage conservation. Cantharidin inadvertently ingested with animal feed may cause illness or death. Little information is available on the effects of cantharidin on ruminant microbial digestion. The objective of our study was to determine cantharidin effects on digestibility of alfalfa and smooth bromegrass (Bromus inermis Leyss) by measuring in vitro digestible dry matter (IVDDM) and cell wall digestion (CWD). Alfalfa dry matter digestibility, measured after IVDDM at 48 and 96 h fermentation periods, decreased as cantharidin concentration increased. Increasing cantharidin concentration also significantly reduced IVDDM of smooth bromegrass at 24 and 96 h digestion time. The CWD of alfalfa and smooth bromegrass decreased as cantharidin concentration increased. These results indicate that ingestion of cantharidin by ruminants may decrease microbial digestion of fibrous feeds and therefore may decrease the efficiency of feed utilization by ruminants.

  4. Pepsin Digestibility of Proteins in Sorghum and Other Major Cereals

    NASA Astrophysics Data System (ADS)

    Mertz, Edwin T.; Hassen, Mohamed M.; Cairns-Whittern, Carleen; Kirleis, Allen W.; Tu, Lichuan; Axtell, John D.

    1984-01-01

    We have shown previously that sorghum is highly digestible in the rat. However, other workers have shown that sorghum is much less digestible than wheat, maize, and rice in young children. Because the rat does not show these digestibility differences, we developed an empirical pepsin digestion method, first reported in 1981, which simulates the digestion values found in children. In this report the method has been improved and used to analyze wheat, maize, rice, millet, and sorghum and certain processed samples of millet and sorghum. The pepsin digestion values parallel those found in children for wheat, maize, rice, and sorghum. In addition, a processed sorghum product that gave a high digestion value in children also gave a high value with the in vitro pepsin method.

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

    PubMed

    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 CH4/kgVS, whereas the wet digester was operated at an OLR of 0.9kgVS/m(3)day, generating about 320NL CH4/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.

  6. Physiology of digestion and the molecular characterization of the major digestive enzymes from Periplaneta americana.

    PubMed

    Tamaki, Fábio K; Pimentel, André C; Dias, Alcides B; Cardoso, Christiane; Ribeiro, Alberto F; Ferreira, Clélia; Terra, Walter R

    2014-11-01

    Cockroaches are among the first insects to appear in the fossil record. This work is part of ongoing research on insects at critical points in the evolutionary tree to disclose evolutionary trends in the digestive characteristics of insects. A transcriptome (454 Roche platform) of the midgut of Periplanetaamericana was searched for sequences of digestive enzymes. The selected sequences were manually curated. The complete or nearly complete sequences showing all characteristic motifs and highly expressed (reads counting) had their predicted sequences checked by cloning and Sanger sequencing. There are two chitinases (lacking mucin and chitin-binding domains), one amylase, two α- and three β-glucosidases, one β-galactosidase, two aminopeptidases (none of the N-group), one chymotrypsin, 5 trypsins, and none β-glucanase. Electrophoretic and enzymological data agreed with transcriptome data in showing that there is a single β-galactosidase, two α-glucosidases, one preferring as substrate maltase and the other aryl α-glucoside, and two β-glucosidases. Chromatographic and enzymological data identified 4 trypsins, one chymotrypsin (also found in the transcriptome), and one non-identified proteinase. The major digestive trypsin is identifiable to a major P. americana allergen (Per a 10). The lack of β-glucanase expression in midguts was confirmed, thus lending support to claims that those enzymes are salivary. A salivary amylase was molecularly cloned and shown to be different from the one from the midgut. Enzyme distribution showed that most digestion occurs under the action of salivary and midgut enzymes in the foregut and anterior midgut, except the posterior terminal digestion of proteins. A counter-flux of fluid may be functional in the midgut of the cockroach to explain the low excretory rate of digestive enzymes. Ultrastructural and immunocytochemical localization data showed that amylase and trypsin are released by both merocrine and apocrine secretion

  7. Hypnosis and upper digestive function and disease

    PubMed Central

    Chiarioni, Giuseppe; Palsson, Olafur S; Whitehead, William E

    2008-01-01

    Hypnosis is a therapeutic technique that primarily involves attentive receptive concentration. Even though a small number of health professionals are trained in hypnosis and lingering myths and misconceptions associated with this method have hampered its widespread use to treat medical conditions, hypnotherapy has gained relevance as an effective treatment for irritable bowel syndrome not responsive to standard care. More recently, a few studies have addressed the potential influence of hypnosis on upper digestive function and disease. This paper reviews the efficacy of hypnosis in the modulation of upper digestive motor and secretory function. The present evidence of the effectiveness of hypnotherapy as a treatment for functional and organic diseases of the upper bowel is also summarized, coupled with a discussion of potential mechanisms of its therapeutic action. PMID:19009639

  8. Use of biochars in anaerobic digestion.

    PubMed

    Mumme, Jan; Srocke, Franziska; Heeg, Kathrin; Werner, Maja

    2014-07-01

    This study investigated the behavior of biochars from pyrolysis (pyrochar) and hydrothermal carbonization (hydrochar) in anaerobic digestion regarding their degradability and their effects on biogas production and ammonia inhibition. A batch fermentation experiment (42°C, 63 days) was conducted in 100mL syringes filled with 30 g inoculum, 2g biochar and four levels of total ammonium nitrogen (TAN). For pyrochar, no clear effect on biogas production was observed, whereas hydrochar increased the methane yield by 32%. This correlates with the hydrochar's larger fraction of anaerobically degradable carbon (10.4% of total carbon, pyrochar: 0.6%). Kinetic and microbiota analyses revealed that pyrochar can prevent mild ammonia inhibition (2.1 g TANk g(-1)). Stronger inhibitions (3.1-6.6 g TAN kg(-1)) were not mitigated, neither by pyrochar nor by hydrochar. Future research should pay attention to biochar-microbe interactions and the effects in continuously-fed anaerobic digesters.

  9. Anaerobic digestion of water hyacinth and sludge

    SciTech Connect

    Biljetina, R.; Srivastava, V.J.; Chynoweth, D.P.; Hayes, T.D.

    1986-01-01

    The Institute of Gas Technology (IGT) has been operating an experimental test unit (ETU) at the Walt Disney World (WDW) wastewater treatment plant to demonstrate the conversion of water hyacinth and sludge to methane in a solids concentrating (SOLCON) digester. Results from 2 years to operation have confirmed earlier laboratory observations that this digester achieves higher methane yields and solids conversion than those observed in continuous stirred tank reactors. Methane yields as high as 0.49 m/sup 3/ kg/sup -1/ (7.9 SCF/lb) volatile solids added have been obtained during steady-state operation on a blend of water hyacinth and sludge. 9 refs., 5 figs., 5 tabs.

  10. USSR Space Life Sciences Digest, issue 29

    NASA Technical Reports Server (NTRS)

    Stone, Lydia Razran (Editor); Teeter, Ronald (Editor); Rowe, Joseph (Editor)

    1991-01-01

    This is the twenty-ninth issue of NASA's Space Life Sciences Digest. It is a double issue covering two issues of the Soviet Space Biology and Aerospace Medicine Journal. Issue 29 contains abstracts of 60 journal papers or book chapters published in Russian and of three Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. A review of a book on environmental hygiene and a list of papers presented at a Soviet conference on space biology and medicine are also included. The materials in this issue were identified as relevant to 28 areas of space biology and medicine. The areas are: adaptation, aviation medicine, biological rhythms, body fluids, botany, cardiovascular and respiratory systems, developmental biology, digestive system, endocrinology, equipment and instrumentation, genetics, habitability and environment effects, hematology, human performance, immunology, life support systems, mathematical modeling, metabolism, musculoskeletal system, neurophysiology, nutrition, personnel selection, psychology, radiobiology, reproductive system, space biology and medicine, and the economics of space flight.

  11. Hog farm in California uses anaerobic digestion

    SciTech Connect

    Swanson, D.

    1995-12-31

    This article describes a system of covered lagoons which help address the waste management problems of hog farmers as well as producing methane used to power generators. Four advantages of anaerobic digestion are described along with the system: energy production from methane; fertilizer for fields; economic development in rural areas; and improved water quality through reduction of nonpoint source pollution. Address for full report is given.

  12. Digestive Diseases - Multiple Languages: MedlinePlus

    MedlinePlus

    ... gov/languages/digestivediseases.html Other topics A-Z A B C D E F G H I J K L M N O P Q R S T U V W XYZ List of All Topics All Digestive Diseases - Multiple Languages To use the sharing features on this page, please enable JavaScript. French (français) Japanese (日本語) Korean (한국어) Russian (Русский) Somali ( ...

  13. Diagnostic Reasoning Model Validation in Digestive Endoscopy

    DTIC Science & Technology

    2007-11-02

    Abstract: The development of a computer -assisted diagnostic system in digestive endoscopy implies to understand the reasoning process of endoscopists. The...that could be used in computer -assisted diagnostic, as referring data. Development of "intelligent" tools, which can retrieve referring images...of the computer -assisted diagnosis system performance was realized with indices, extracted from endoscopist talks. The system responses were compared

  14. Anaerobic digestion of municipal solid waste

    SciTech Connect

    Dasgupta, A.; Nemerow, N.L.; Farooq, S.; Daly, E.L. Jr.; Sengupta, S.; Gerrish, H.P.; Wong, K.F.

    1981-03-01

    A demonstration anaerobic digestion plant has been installed at Pompano Beach, Florida, capable of treating 100 tons per day of municipal solid waste. The suitability of this process and its environmental effects at a full scale operation level is being examined. The study presented and discussed in this paper had as its main objective the characterization of various waste streams and an assessment of their environmental effects if discharged into the environment.

  15. Mesophilic digestion kinetics of manure slurry.

    PubMed

    Karim, Khursheed; Klasson, K Thomas; Drescher, Sadie R; Ridenour, Whitney; Borole, Abhijeet P; Al-Dahhan, Muthanna H

    2007-09-01

    Anaerobic digestion kinetics study of cow manure was performed at 35 degrees C in bench-scale gas-lift digesters (3.78 l working volume) at eight different volatile solids (VS) loading rates in the range of 1.11-5.87 g l-1 day-1. The digesters produced methane at the rates of 0.44-1.18 l l-1 day-1, and the methane content of the biogas was found to increase with longer hydraulic retention time (HRT). Based on the experimental observations, the ultimate methane yield and the specific methane productivity were estimated to be 0.42 l CH4 (g VS loaded)-1 and 0.45 l CH4 (g VS consumed)-1, respectively. Total and dissolved chemical oxygen demand (COD) consumptions were calculated to be 59-17% and 78-43% at 24.4-4.6 days HRTs, respectively. Maximum concentration of volatile fatty acids in the effluent was observed as 0.7 g l-1 at 4.6 days HRT, while it was below detection limit at HRTs longer than 11 days. The observed methane production rate did not compare well with the predictions of Chen and Hashimoto's [1] and Hill's [2] models using their recommended kinetic parameters. However, under the studied experimental conditions, the predictions of Chen and Hashimoto's [1] model compared better to the observed data than that of Hill's [2] model. The nonlinear regression analysis of the experimental data was performed using a derived methane production rate model, for a completely mixed anaerobic digester, involving Contois kinetics [3] with endogenous decay. The best fit values for the maximum specific growth rate (micro m) and dimensionless kinetic parameter (K) were estimated as 0.43 day-1 and 0.89, respectively. The experimental data were found to be within 95% confidence interval of the prediction of the derived methane production rate model with the sum of residual squared error as 0.02.

  16. Video Games and Children. ERIC Digest.

    ERIC Educational Resources Information Center

    Cesarone, Bernard

    This digest examines data on video game use by children, explains ratings of video game violence, and reviews research on the effects of video games on children and adolescents. A recent study of seventh and eighth graders found that 65% of males and 57% of females played 1 to 6 hours of video games at home per week, and 38% of males and 16% of…

  17. Toxicologic disease of the digestive tract.

    PubMed

    Garland, T

    2000-03-01

    There is a diverse and long list of toxicants that can affect the digestive system of food-producing animals. The plants and other natural toxicants discussed in this article are those primarily affecting the GI system. A number of other plants may also affect the digestive tract, but the effects from these are considered secondary and less pronounced. Often, plant poisonings affecting the digestive tract present with similar clinical signs, and a good thorough history is necessary to help differentiate between them. Moreover, a careful walk through the pasture with a keen eye to note plants that have been browsed or grazed may greatly assist the history. In cases where toxins are suspected as the cause of a GI disorder, consultation with a veterinary toxicologist at a diagnostic laboratory may be indicated. These professionals are knowledgeable about a wide variety of natural and other toxicants that may be present in your area. They can help with developing a differential diagnosis and the selection of appropriate samples to confirm the diagnosis.

  18. Disintegration impact on sludge digestion process.

    PubMed

    Dauknys, Regimantas; Rimeika, Mindaugas; Jankeliūnaitė, Eglė; Mažeikienė, Aušra

    2016-11-01

    The anaerobic sludge digestion is a widely used method for sludge stabilization in wastewater treatment plant. This process can be improved by applying the sludge disintegration methods. As the sludge disintegration is not investigated enough, an analysis of how the application of thermal hydrolysis affects the sludge digestion process based on full-scale data was conducted. The results showed that the maximum volatile suspended solids (VSS) destruction reached the value of 65% independently on the application of thermal hydrolysis. The average VSS destruction increased by 14% when thermal hydrolysis was applied. In order to have the maximum VSS reduction and biogas production, it is recommended to keep the maximum defined VSS loading of 5.7 kg VSS/m(3)/d when the thermal hydrolysis is applied and to keep the VSS loading between 2.1-2.4 kg VSS/m(3)/d when the disintegration of sludge is not applied. The application of thermal hydrolysis leads to an approximately 2.5 times higher VSS loading maintenance comparing VSS loading without the disintegration; therefore, digesters with 1.8 times smaller volume is required.

  19. Human digestion--a processing perspective.

    PubMed

    Boland, Mike

    2016-05-01

    The human digestive system is reviewed in the context of a process with four major unit operations: oral processing to reduce particle size and produce a bolus; gastric processing to initiate chemical and enzymatic breakdown; small intestinal processing to break down macromolecules and absorb nutrients; and fermentation and water removal in the colon. Topics are highlighted about which we need to know more, including effects of aging and dentition on particle size in the bolus, effects of different patterns of food and beverage intake on nutrition, changes in saliva production and composition, mechanical effects of gastric processing, distribution of pH in the stomach, physicochemical and enzymatic effects on nutrient availability and uptake in the small intestine, and the composition, effects of and changes in the microbiota of the colon. Current topics of interest including food synergy, gut-brain interactions, nutritional phenotype and digestion in the elderly are considered. Finally, opportunities for food design based on an understanding of digestive processing are discussed.

  20. Efficient Web Change Monitoring with Page Digest

    SciTech Connect

    Buttler, D J; Rocco, D; Liu, L

    2004-02-20

    The Internet and the World Wide Web have enabled a publishing explosion of useful online information, which has produced the unfortunate side effect of information overload: it is increasingly difficult for individuals to keep abreast of fresh information. In this paper we describe an approach for building a system for efficiently monitoring changes to Web documents. This paper has three main contributions. First, we present a coherent framework that captures different characteristics of Web documents. The system uses the Page Digest encoding to provide a comprehensive monitoring system for content, structure, and other interesting properties of Web documents. Second, the Page Digest encoding enables improved performance for individual page monitors through mechanisms such as short-circuit evaluation, linear time algorithms for document and structure similarity, and data size reduction. Finally, we develop a collection of sentinel grouping techniques based on the Page Digest encoding to reduce redundant processing in large-scale monitoring systems by grouping similar monitoring requests together. We examine how effective these techniques are over a wide range of parameters and have seen an order of magnitude speed up over existing Web-based information monitoring systems.

  1. [Digestion-flame atomic absorption spectroscopy].

    PubMed

    Xu, Liang; Hu, Jian-Guo; Liu, Rui-Ping; Wang, Zhi-Min; Narenhua

    2008-01-01

    A microwave digestion-flame atomic absorption spectroscopy (FAAS) method was developed for the determination of metal elements Na, Zn, Cu, Fe, Mn, Ca and Mg in Mongolian patents. The instrument parameters for the determination were optimized, and the appropriate digestion solvent was selected. The recovery of the method was between 95.8% and 104.3%, and the RSD was between 1.6% and 4.2%. The accuracy and precision of the method was tested by comparing the values obtained from the determination of the standard sample, bush twigs and leaves (GSV-1) by this method with the reference values of GSV-1. The determination results were found to be basically consistent with the reference values. The microwave digestion technique was applied to process the samples, and the experimental results showed that compared to the traditional wet method, the present method has the merits of simplicity, saving agents, rapidness, and non-polluting. The method was accurate and reliable, and could be used to determine the contents of seven kinds of metal elements in mongolian patents.

  2. Method of digesting an explosive nitro compound

    DOEpatents

    Shah, Manish M.

    2000-01-01

    The present invention is a process wherein bleaching oxidants are used to digest explosive nitro compounds. The process has an excellent reaction rate for digesting explosives and operates under multivariate conditions. Reaction solutions may be aqueous, non-aqueous or a combination thereof, and can also be any pH, but preferably have a pH between 2 and 9. The temperature may be ambient as well as any temperature above which freezing of the solution would occur and below which any degradation of the bleaching oxidant would occur or below which any explosive reaction would be initiated. The pressure may be any pressure, but is preferably ambient or atmospheric, or a pressure above a vapor pressure of the aqueous solution to avoid boiling of the solution. Because the bleaching oxidant molecules are small, much smaller than an enzyme molecule for example, they can penetrate the microstructure of plastic explosives faster. The bleaching oxidants generate reactive hydroxyl radicals, which can destroy other organic contaminants, if necessary, along with digesting the explosive nitro compound.

  3. Vacuum evaporation treatment of digestate: full exploitation of cogeneration heat to process the whole digestate production.

    PubMed

    Guercini, S; Castelli, G; Rumor, C

    2014-01-01

    Vacuum evaporation represents an interesting and innovative solution for managing animal waste surpluses in areas with high livestock density. To reduce operational costs, a key factor is the availability of an inexpensive source of heat, such as that coming from an anaerobic digestion (AD) plant. The aim of this study was to test vacuum evaporation for the treatment of cattle slurry digestate focusing on heat exploitation. Tests were performed with a pilot plant fed with the digestate from a full-scale AD plant. The results were used to evaluate if and how cogeneration heat can support both the AD plant and the subsequent evaporation of the whole daily digestate production in a full-scale plant. The concentrate obtained (12% total solids) represents 40-50% of the influent. The heat requirement is 0.44 kWh/kg condensate. Heat power availability exceeding the needs of the digestor ranges from 325 (in winter) to 585 kW (in summer) versus the 382 kW required for processing the whole digestate production. To by-pass fluctuations, we propose to use the heat coming from the cogenerator directly in the evaporator, tempering the digestor with the latent heat of distillation vapor.

  4. Enhanced anaerobic digestion of waste activated sludge digestion by the addition of zero valent iron.

    PubMed

    Feng, Yinghong; Zhang, Yaobin; Quan, Xie; Chen, Suo

    2014-04-01

    Anaerobic digestion is promising technology to recover energy from waste activated sludge. However, the sludge digestion is limited by its low efficiency of hydrolysis-acidification. Zero valent iron (ZVI) as a reducing material is expected to enhance anaerobic process including the hydrolysis-acidification process. Considering that, ZVI was added into an anaerobic sludge digestion system to accelerate the sludge digestion in this study. The results indicated that ZVI effectively enhanced the decomposition of protein and cellulose, the two main components of the sludge. Compared to the control test without ZVI, the degradation of protein increased 21.9% and the volatile fatty acids production increased 37.3% with adding ZVI. More acetate and less propionate are found during the hydrolysis-acidification with ZVI. The activities of several key enzymes in the hydrolysis and acidification increased 0.6-1 time. ZVI made the methane production raise 43.5% and sludge reduction ratio increase 12.2 percent points. Fluorescence in situ hybridization analysis showed that the abundances of hydrogen-consuming microorganisms including homoacetogens and hydrogenotrophic methanogens with ZVI were higher than the control, which reduced the H2 accumulation to create a beneficial condition for the sludge digestion in thermodynamics.

  5. Enhancing post anaerobic digestion of full-scale anaerobically digested sludge using free nitrous acid treatment.

    PubMed

    Zhang, Tingting; Wang, Qilin; Ye, Liu; Yuan, Zhiguo

    2016-05-01

    In some wastewater treatment plants (WWTPs), the ever increasing production of sludge with the expanding population overloaded the anaerobic digestion which compromises the sludge reduction efficiency. Post anaerobic digestion of anaerobically digested sludge (ADS) has been applied to enhance sludge reduction, however, to a very limited extent. This study verified the effectiveness of free nitrous acid (FNA i.e. HNO2) pre-treatment on enhancing full-scale ADS degradation in post anaerobic digestion. The ADS collected from a full-scale WWTP was subject to FNA treatment at concentrations of 0.77, 1.54, 2.31, 3.08, and 3.85 mg N/L for 24 h followed by biochemical methane potential tests. The FNA treatment at all concentrations resulted in an increase (from 1.5-3.1 % compared to the control) in sludge reduction with the highest improvement achieved at 0.77 mg HNO2-N/L. The FNA treatment at this concentration also resulted in the highest increase in methane production (40 %) compared to the control. The economic analysis indicates that FNA treatment is economically attractive for enhancing post anaerobic digestion of full-scale ADS.

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

    SciTech Connect

    Bayr, S. 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.

  7. Digestive enzyme activity of two stonefly species (Insecta, Plecoptera) and their feeding habits.

    PubMed

    de Figueroa, J M Tierno; Trenzado, C E; López-Rodríguez, M J; Sanz, A

    2011-11-01

    The digestive enzymes of two stoneflies species, Hemimelaena flaviventris and Isoperla morenica, were studied for the first time. These species are temporary water inhabitants and exhibit great feeding plasticity. Although they are traditionally referred to as predators, a previous study revealed that H. flaviventris incorporates some diatoms into its diet in addition to feeding usually on several prey, and I. morenica (in that study under the name of I. curtata) only feeds on animals occasionally. The enzymatic activities of digestive amylase, lipase, protease, trypsin and chymotrypsin were determined for each species at the same developmental stage. The results show that H. flaviventris has a greater digestive enzymatic pool and higher relative and absolute protease, lipase and trypsin activities than I. morenica. The latter has a relative higher amylase activity. As higher amylase activity is typical of phytophagous species and higher protease activity typical of carnivorous species; these results reveal that H. flaviventris is a more efficient zoophagous species than I. morenica. The ecological implications of these findings, including the higher secondary production of H. flaviventris in its habitat, are discussed.

  8. Salivary digestive enzymes of the wheat bug, Eurygaster integriceps (Insecta: Hemiptera: Scutelleridae).

    PubMed

    Mehrabadi, Mohammad; Bandani, Ali Reza; Dastranj, Mehdi

    2014-06-01

    The digestive enzymes from salivary gland complexes (SGC) of Eurygaster integriceps, and their response to starvation and feeding were studied. Moreover, digestive amylases were partially purified and characterized by ammonium sulfate precipitation and gel filtration chromatography. The SGC are composed of two sections, the principal glands and accessory glands. The principal glands are further divided into the anterior lobes and posterior lobes. The SGC main enzyme was α-amylase, which hydrolyzed starch better than glycogen. The other carbohydrases were also present in the SGC complexes. Enzymatic activities toward mannose (α/β-mannosidases) were little in comparison to activities against glucose (α/β-glucosidases) and galactose (α/β-galactosidases), the latter being the greatest. Acid phosphatase showed higher activity than alkaline phosphatase. There was no measurable activity for lipase and aminopeptidase. Proteolytic activity was detected against general and specific protease substrates. Activities of all enzymes were increased in response to feeding in comparison to starved insects, revealing their induction and secretion in response to feeding pulse. The SGC amylases eluted in four major peaks and post-electrophoretic detection of the α-amylases demonstrated the existence of at least five isoamylases in the SGC. The physiological implication of these findings in pre-oral digestion of E. integriceps is discussed.

  9. Blackberry subjected to in vitro gastrointestinal digestion affords protection against Ethyl Carbamate-induced cytotoxicity.

    PubMed

    Chen, Wei; Xu, Yang; Zhang, Lingxia; Su, Hongming; Zheng, Xiaodong

    2016-12-01

    Ethyl Carbamate (EC) was detected in many fermented foods. Previous studies indicated that frequent exposure to ethyl carbamate may increase the risk to suffer from cancers. Blackberry is rich in polyphenols and possesses potent antioxidant activity. This study aims to investigate the protective effect of blackberry homogenates produced before (BH) and after in vitro simulated gastrointestinal digestion (BD) on EC-induced toxicity in Caco-2 cells. Our results showed that blackberry homogenates after digestion (BD) was more effective than that before digestion (BH) in ameliorating EC-induced toxicity in Caco-2 cells. Further investigation revealed that BD remarkably attenuated EC-induced toxicity through restoring mitochondrial function, inhibiting glutathione depletion and decreasing overproduction of intracellular reactive oxygen species. Additionally, LC-MS result implied that the better protective capacity of BD may be related to the increased content of two anthocyanins (cyanidin-3-glucoside and cyanidin-3-dioxalyglucoside). Overall, the present study may give implication to prevent EC-induced health problem.

  10. Improving products of anaerobic sludge digestion by microaeration.

    PubMed

    Jenicek, P; Celis, C A; Krayzelova, L; Anferova, N; Pokorna, D

    2014-01-01

    Biogas, digested sludge and sludge liquor are the main products of anaerobic sludge digestion. Each of the products is influenced significantly by specific conditions of the digestion process. Therefore, any upgrade of the digestion technology must be considered with regard to quality changes in all products. Microaeration is one of the methods used for the improvement of biogas quality. Recently, microaeration has been proved to be a relatively simple and highly efficient biological method of sulfide removal in the anaerobic digestion of biosolids, but little attention has been paid to comparing the quality of digested sludge and sludge liquor in the anaerobic and microaerobic digestion and that is why this paper primarily deals with this area of research. The results of the long-term monitoring of digested sludge quality and sludge liquor quality in the anaerobic and microaerobic digesters suggest that products of both technologies are comparable. However, there are several parameters in which the 'microaerobic' products have a significantly better quality such as: sulfide (68% lower) and soluble chemical oxygen demand (COD) (33% lower) concentrations in the sludge liquor and the lower foaming potential of the digested sludge.

  11. Co-digestion of grease trap sludge and sewage sludge.

    PubMed

    Davidsson, A; Lövstedt, C; Jansen, J la Cour; Gruvberger, C; Aspegren, H

    2008-01-01

    Redirection of organic waste, from landfilling or incineration, to biological treatment such as anaerobic digestion is of current interest in the Malmö-Copenhagen region. One type of waste that is expected to be suitable for anaerobic digestion is sludge from grease traps. Separate anaerobic digestion of this waste type and co-digestion with sewage sludge were evaluated. The methane potential was measured in batch laboratory tests, and the methane yield was determined in continuous pilot-scale digestion. Co-digestion of sludge from grease traps and sewage sludge was successfully performed both in laboratory batch and continuous pilot-scale digestion tests. The addition of grease trap sludge to sewage sludge digesters was seen to increase the methane yield of 9-27% when 10-30% of sludge from grease traps (on VS-basis) was added. It was also seen that the grease trap sludge increases the methane yield without increasing the sludge production. Single-substrate digestion of grease trap sludge gave high methane potentials in batch tests, but could not reach stable methane production in continuous digestion.

  12. Environmental assessment of digestate treatment technologies using LCA methodology.

    PubMed

    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.

  13. Balancing hygienization and anaerobic digestion of raw sewage sludge.

    PubMed

    Astals, S; Venegas, C; Peces, M; Jofre, J; Lucena, F; Mata-Alvarez, J

    2012-12-01

    The anaerobic digestion of raw sewage sludge was evaluated in terms of process efficiency and sludge hygienization. Four different scenarios were analyzed, i.e. mesophilic anaerobic digestion, thermophilic anaerobic digestion and mesophilic anaerobic digestion followed by a 60 °C or by an 80 °C hygienization treatment. Digester performance (organic matter removal, process stability and biogas yield) and the hygienization efficiency (reduction of Escherichia coli, somatic coliphages and F-specific RNA phages) were the main examined factors. Moreover, a preliminary economical feasibility study of each option was carried out throughout an energy balance (heat and electricity). The obtained results showed that both thermophilic anaerobic digestion and mesophilic anaerobic digestion followed by a hygienization step were able to produce an effluent sludge that fulfills the American and the European legislation for land application. However, higher removal efficiencies of indicators were obtained when a hygienization post-treatment was present. Regarding the energy balance, it should be noted that all scenarios have a significant energy surplus. Particularly, positive heat balances will be obtained for the thermophilic anaerobic digestion and for the mesophilic anaerobic digestion followed by 60 °C hygienization post-treatment if an additional fresh-sludge/digested sludge heat exchanger is installed for energy recovery.

  14. Effects of lactic acid fermentation and gamma irradiation of barley on antinutrient contents and nutrient digestibility in mink (Mustela vison) with and without dietary enzyme supplement.

    PubMed

    Skrede, Anders; Sahlstrøm, Stefan; Ahlstrøm, Oystein; Connor, Kirsti Hjelme; Skrede, Grete

    2007-06-01

    The experiment was conducted to study the effects of fermentation of barley, using two different strains of lactic acid bacteria, a Lactobacillus plantarum/pentosus strain isolated from spontaneously fermented rye sourdough (AD2) and a starch-degrading Lactobacillus plantarum (AM4), on contents of mixed-linked (1 --> 3) (1 --> 4)-beta-glucans, alpha-amylase inhibitor activity, inositol phosphates, and apparent digestibility of macronutrients in mink. Effects of fermentation were compared with effects of gamma irradiation (gamma-irradiation: 60Co gamma-rays at 25 kGy). The diets were fed to mink with and without a supplementary enzyme preparation. Both lactic acid fermentation and gamma-irradiation followed by soaking and incubation, reduced concentrations of soluble beta-glucans, phytate and alpha-amylase inhibitor activity. Dietary enzyme supplementation increased significantly digestibility of crude protein, fat, starch and crude carbohydrate (CHO). Fermentation of the barley increased digestibility of starch and CHO. Fermentation with lactic acid bacteria AD2 resulted in higher starch and CHO digestibility than strain AM4, and had greater effect than gamma-irradiation, soaking and incubation. The highest digestibility of starch and CHO was obtained after AD2 fermentation followed by enzyme supplementation. It is concluded that both lactic acid fermentation of barley and enzyme supplementation have positive nutritional implications in the mink by limiting the effects of antinutrients and improving digestibility and energy utilization.

  15. Interfacial & colloidal aspects of lipid digestion.

    PubMed

    Wilde, P J; Chu, B S

    2011-06-09

    Amongst the main issues challenging the food manufacturing sector, health and nutrition are becoming increasingly important. Global concerns such as obesity, the ageing population and food security will have to be addressed. Food security is not just about assuring food supply, but is also about optimising nutritional delivery from the food that is available [1]. Therefore one challenge is to optimise the health benefits from the lipids and lipid soluble nutrients. Colloid scientists have an affinity for lipids because they are water insoluble, however this presents a challenge to the digestive system, which has to convert them to structures that are less insoluble so they are available for uptake. Despite this, the human digestive system is remarkably effective at digesting and absorbing most lipids. This is primarily driven through maximising energy intake, as lipids possess the highest calorific value, which was a survival trait to survive times of famine, but is now an underlying cause of obesity in developed countries with high food availability. The critical region here is the lipid-water interface, where the key reactions take place to solubilise lipids and lipid soluble nutrients. Digestive lipases have to adsorb to the oil water interface in order to hydrolyse triacylglycerols into fatty acids and mono glycerides, which accumulate at the interface [2], and inhibit lipase activity. Pancreatic lipase, which is responsible for the majority of lipid hydrolysis, also requires the action of bile salts and colipase to function effectively. Bile salts both aid the adsorption of co-lipase and lipase, and help solubilise the lipolysis products which have accumulated at the interface, into mixed micelles composing bile salts and a range of other lipids, to facilitate transport to the gut mucosal surface prior to uptake and absorption. The process can be affected by the lipid type, as shorter chain, fatty acids are more easily absorbed, whereas the uptake of longer

  16. The glycemic response does not reflect the in vivo starch digestibility of fiber-rich wheat products in healthy men.

    PubMed

    Eelderink, Coby; Moerdijk-Poortvliet, Tanja C W; Wang, Hongwei; Schepers, Marianne; Preston, Tom; Boer, Theo; Vonk, Roel J; Schierbeek, Henk; Priebe, Marion G

    2012-02-01

    Starchy food products differ in the rate of starch digestion, which can affect their metabolic impact. In this study, we examined how the in vivo starch digestibility is reflected by the glycemic response, because this response is often used to predict starch digestibility. Ten healthy male volunteers [age 21 ± 0.5 y, BMI 23 ± 0.6 kg/m² (mean ± SEM)] participated in a cross-over study, receiving three different meals: pasta with normal wheat bran (PA) and bread with normal (CB) or purple wheat bran (PBB). Purple wheat bran was added in an attempt to decrease the rate of starch digestion. The meals were enriched in ¹³C and the dual isotope technique was applied to calculate the rate of appearance of exogenous glucose (RaE). The ¹³C-isotopic enrichment of glucose in plasma was measured with GC/combustion/isotope ratio MS (IRMS) and liquid chromatography/IRMS. Both IRMS techniques gave similar results. Plasma glucose concentrations [2-h incremental AUC (iAUC)] did not differ between the test meals. The RaE was similar after consumption of CB and PBB, showing that purple wheat bran in bread does not affect in vivo starch digestibility. However, the iAUC of RaE after men consumed PA was less than after they consumed CB (P < 0.0001) despite the similar glucose response. To conclude, the glycemic response does not always reflect the in vivo starch digestibility. This could have implications for intervention studies in which the glycemic response is used to characterize test products.

  17. Predicting the apparent viscosity and yield stress of mixtures of primary, secondary and anaerobically digested sewage sludge: Simulating anaerobic digesters.

    PubMed

    Markis, Flora; Baudez, Jean-Christophe; Parthasarathy, Rajarathinam; Slatter, Paul; Eshtiaghi, Nicky

    2016-09-01

    Predicting the flow behaviour, most notably, the apparent viscosity and yield stress of sludge mixtures inside the anaerobic digester is essential because it helps optimize the mixing system in digesters. This paper investigates the rheology of sludge mixtures as a function of digested sludge volume fraction. Sludge mixtures exhibited non-Newtonian, shear thinning, yield stress behaviour. The apparent viscosity and yield stress of sludge mixtures prepared at the same total solids concentration was influenced by the interactions within the digested sludge and increased with the volume fraction of digested sludge - highlighted using shear compliance and shear modulus of sludge mixtures. However, when a thickened primary - secondary sludge mixture was mixed with dilute digested sludge, the apparent viscosity and yield stress decreased with increasing the volume fraction of digested sludge. This was caused by the dilution effect leading to a reduction in the hydrodynamic and non-hydrodynamic interactions when dilute digested sludge was added. Correlations were developed to predict the apparent viscosity and yield stress of the mixtures as a function of the digested sludge volume fraction and total solids concentration of the mixtures. The parameters of correlations can be estimated using pH of sludge. The shear and complex modulus were also modelled and they followed an exponential relationship with increasing digested sludge volume fraction.

  18. Changes in chemical composition and digestibility of three maize stover components digested by white-rot fungi.

    PubMed

    Lynch, J P; O'Kiely, P; Murphy, R; Doyle, E M

    2014-08-01

    Maize stover (total stem and leaves) is not considered a ruminant feed of high nutritive value. Therefore, an improvement in its digestibility may increase the viability of total forage maize production systems in marginal growth regions. The objective of this study was to describe the changes in chemical composition during the storage of contrasting components of maize stover (leaf, upper stem and lower stem) treated with either of two lignin degrading white-rot fungi (WRF; Pleurotus ostreatus, Trametes versicolor). Three components of maize stover (leaf, upper stem and lower stem), harvested at a conventional maturity for silage production, were digested with either of two WRF for one of four digestion durations (1-4 months). Samples taken prior to fungal inoculation were used to benchmark the changes that occurred. The degradation of acid detergent lignin was observed in all sample types digested with P. ostreatus; however, the loss of digestible substrate in all samples inoculated with P. ostreatus was high, and therefore, P. ostreatus-digested samples had a lower dry matter digestibility than samples prior to inoculation. Similarly, T. veriscolor-digested leaf underwent a non-selective degradation of the rumen-digestible components of fibre. The changes in chemical composition of leaf, upper stem and lower stem digested with either P. ostreatus or T. veriscolor were not beneficial to the feed value of the forage, and incurred high DM losses.

  19. Comparison of five in vitro digestion models to study the bioaccessibility of soil contaminants.

    PubMed

    Oomen, Agnes G; Hack, Alfons; Minekus, Mans; Zeijdner, Evelijn; Cornelis, Christa; Schoeters, Greet; Verstraete, Willy; Van de Wiele, Tom; Wragg, Joanna; Rompelberg, Cathy J M; Sips, Adriënne J A M; Van Wijnen, Joop H

    2002-08-01

    Soil ingestion can be a major exposure route for humans to many immobile soil contaminants. Exposure to soil contaminants can be overestimated if oral bioavailability is not taken into account. Several in vitro digestion models simulating the human gastrointestinal tract have been developed to assess mobilization of contaminants from soil during digestion, i.e., bioaccessibility. Bioaccessibility is a crucial step in controlling the oral bioavailability for soil contaminants. To what extent in vitro determination of bioaccessibility is method dependent has, until now, not been studied. This paper describes a multi-laboratory comparison and evaluation of five in vitro digestion models. Their experimental design and the results of a round robin evaluation of three soils, each contaminated with arsenic, cadmium, and lead, are presented and discussed. A wide range of bioaccessibility values were found for the three soils: for As 6-95%, 1-19%, and 10-59%; for Cd 7-92%, 5-92%, and 6-99%; and for Pb 4-91%, 1-56%, and 3-90%. Bioaccessibility in many cases is less than 50%, indicating that a reduction of bioavailability can have implications for health risk assessment. Although the experimental designs of the different digestion systems are distinct, the main differences in test results of bioaccessibility can be explained on the basis of the applied gastric pH. High values are typically observed for a simple gastric method, which measures bioaccessibility in the gastric compartment at low pHs of 1.5. Other methods that also apply a low gastric pH, and include intestinal conditions, produce lower bioaccessibility values. The lowest bioaccessibility values are observed for a gastrointestinal method which employs a high gastric pH of 4.0.

  20. Soil sample preparation using microwave digestion for uranium analysis

    SciTech Connect

    MOHAGHEGHI,AMIR H.; PRESTON,ROSE; AKBARZADEH,MANSOOR; BAKHTIAR,STEVEN

    2000-04-05

    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.

  1. Biogas production in batch and semicontinuous digesters using water hyacinth

    SciTech Connect

    Vaidyanathan, S.; Kavadia, K.M.; Shroff, K.C.; Mahajan, S.P.

    1985-01-01

    Semicontinuous digestion experiments at ambient temperature conducted in a pilot size mixed digester using groundwater hyacinth showed that maximum specific methane production rate was obtained at the highest volatile solids loading rate and lowest hydraulic detention time. Specific methane production rate is correlated with volatile solids loading rate; this correlation offers a simple tool to design semicontinuous biogas digesters for commercial plants using water hyacinth.

  2. Application of microwave digestion to the analysis of peat

    USGS Publications Warehouse

    Papp, C.S.E.; Fischer, L.B.

    1987-01-01

    A microwave digestion technique for the dissolution of peat is described and compared with a dry ashing method and a nitric - perchloric - hydrofluoric acid wet digestion. Peat samples with different organic matter contents were used and Ca, Mg, Fe, AI, Na, K, Mn, Zn, Cu and Li were determined by atomic absoprtion spectrometry. The results obtained using the three dissolution techniques were in good agreement. The microwave method has the advantage of digesting the samples in less than 2 h and uses less acid than the conventional wet digestion method. Keeping the volume of the acid mixture as small as possible minimises contamination and leads to lower blank values.

  3. Methane production by anaerobic digestion of water hyacinth (Eichhornia crassipes)

    SciTech Connect

    Klass, D.L.; Ghosh, S.

    1980-01-01

    Water hyacinth under conventional high-rate digestion conditions exhibited higher methane yields and energy recovery efficiencies when grown in sewage-fed lagoons as compared to the corresponding values obtained with water hyacinth grown in a fresh-water pond. Mesophilic digestion provided the highest feed energy recovered in the product gas as methane while thermophilic digestion, when operated at sufficiently high loading rates and reduced detention times, gave the highest specific methane production rates. Methane yields, volatile solids reduction, and energy recovery as methane for the sewage-grown water hyacinth were in the same range as those observed for other biomass substrates when digested under similar conditions.

  4. Methane production by anaerobic digestion of water hyacinth (Eichhornia crassipes)

    SciTech Connect

    Klass, D.L.; Ghosh, S.

    1980-01-01

    Water hyacinth under conventional high-rate digestion conditions exhibited higher CH4 yields and energy recovery efficiencies when grown in sewage-fed lagoons than when grown in a fresh water pond. Mesophilic digestion provided the highest recovery of feed energy in the product gas as CH4, while thermophilic digestion, when operated at sufficiently high loading rates and reduced detention times, gave the highest specific CH4 production rates. CH4 yields, volatile solids reduction, and energy recovery as CH4 from the sewage-grown water hyacinth were in the same range as those observed for other biomass substrates when digested under similar conditions.

  5. Optimizing the Logistics of Anaerobic Digestion of Manure

    NASA Astrophysics Data System (ADS)

    Ghafoori, Emad; Flynn, Peter C.

    Electrical power production from the combustion of biogas from anaerobic digestion (AD) of manure is a means of recovering energy from animal waste. We evaluate the lowest cost method of moving material to and from centralized AD plants serving multiple confined feeding operations. Two areas are modeled, Lethbridge County, Alberta, Canada, an area of concentrated beef cattle feedlots, and Red Deer County, Alberta, a mixed-farming area with hog, dairy, chicken and beef cattle farms, and feedlots. We evaluate two types of AD plant: ones that return digestate to the source confined feeding operation for land spreading (current technology), and ones that process digestate to produce solid fertilizer and a dischargeable water stream (technology under development). We evaluate manure and digestate trucking, trucking of manure with return of digestate by pipelines, and pipelining of manure plus digestate. We compare the overall cost of power from these scenarios to farm or feedlot-based AD units. For a centralized AD plant with digestate return for land spreading the most economical transport option for manure plus digestate is by truck for the mixed-farming area and by pipelines for the concentrated feedlot area. For a centralized AD plant with digestate processing, the most economical transport option is trucking of manure for both cases.

  6. VALIDATION FOR THE PERMANGANATE DIGESTION OF REILLEX HPQ ANION RESIN

    SciTech Connect

    Kyser, E.

    2009-09-23

    The flowsheet for the digestion of Reillex{trademark} HPQ was validated both under the traditional alkaline conditions and under strongly acidic conditions. Due to difficulty in performing a pH adjustment in the large tank where this flowsheet must be performed, the recommended digestion conditions were changed from pH 8-10 to 8 M HNO{sub 3}. Thus, no pH adjustment of the solution is required prior to performing the permanganate addition and digestion and the need to sample the digestion tank to confirm appropriate pH range for digestion may be avoided. Neutralization of the acidic digestion solution will be performed after completion of the resin digestion cycle. The amount of permanganate required for this type of resin (Reillex{trademark} HPQ) was increased from 1 kg/L resin to 4 kg/L resin to reduce the amount of residual resin solids to a minimal amount (<5%). The length of digestion time at 70 C remains unchanged at 15 hours. These parameters are not optimized but are expected to be adequate for the conditions. The flowsheet generates a significant amount of fine manganese dioxide (MnO{sub 2}) solids (1.71 kg/L resin) and involves the generation of a significant liquid volume due to the low solubility of permanganate. However, since only two batches of resin (40 L each) are expected to be digested, the total waste generated is limited.

  7. Kenaf Bast Fibers—Part I: Hermetical Alkali Digestion

    DOE PAGES

    Shi, Jinshu; Shi, Sheldon Q.; Barnes, H. Michael; ...

    2011-01-01

    The objective of this study was to develop a hermetical alkali digestion process to obtain single cellulosic fibers from kenaf bast. Kenaf bast were hermetically digested into single fiber using a 5% sodium hydroxide solution for one hour at four different temperatures (80 ° C, 110 ° C, 130 ° C, and 160 ° C). The hermetical digestion process used in this study produced fibers with high cellulose content (84.2–92.3%) due to the removal of lignin and hemicelluloses. The surface hardness and elastic modulus of the fibers digested at 130 ° C and 160 ° C were improved significantlymore » compared with those digested at 80 ° C. The tensile modulus and tensile strength of the individual fibers reduced as the digestion temperature increased from 110 ° C to 160 ° C. Micropores were generated in fiber cell wall when the fibers were digested at 130 ° C and 160 ° C. The studies on the composites that were made from polypropylene reinforced with the digested fibers indicated that the compatibility between the digested fibers and polypropylene matrix was poor.« less

  8. Phylogenetic analysis of the evolution of lactose digestion in adults.

    PubMed

    Holden, C; Mace, R

    1997-10-01

    In most of the world's population the ability to digest lactose declines sharply after infancy. High lactose digestion capacity in adults is common only in populations of European and circum-Mediterranean origin and is thought to be an evolutionary adaptation to millennia of drinking milk from domestic livestock. Milk can also be consumed in a processed form, such as cheese or soured milk, which has a reduced lactose content. Two other selective pressures for drinking fresh milk with a high lactose content have been proposed: promotion of calcium uptake in high-latitude populations prone to vitamin-D deficiency and maintainance of water and electrolytes in the body in highly and environments. These three hypotheses are all supported by the geographic distribution of high lactose digestion capacity in adults. However, the relationships between environmental variables and adult lactose digestion capacity are highly confounded by the shared ancestry of many populations whose lactose digestion capacity has been tested. The three hypotheses for the evolution of high adult lactose digestion capacity are tested here using a comparative method of analysis that takes the problem of phylogenetic confounding into account. This analysis supports the hypothesis that high adult lactose digestion capacity is an adaptation to dairying but does not support the hypotheses that lactose digestion capacity is additionally selected for either at high latitudes or in highly arid environments. Furthermore, methods using maximum likelihood are used to show that the evolution of milking preceded the evolution of high lactose digestion.

  9. Agronomic characteristics of five different urban waste digestates.

    PubMed

    Tampio, Elina; Salo, Tapio; Rintala, Jukka

    2016-03-15

    The use of digestate in agriculture is an efficient way to recycle materials and to decrease the use of mineral fertilizers. The agronomic characteristics of the digestates can promote plant growth and soil properties after digestate fertilization but also harmful effects can arise due to digestate quality, e.g. pH, organic matter and heavy metal content. The objective of this study was to evaluate the differences and similarities in agronomic characteristics and the value of five urban waste digestates from different biogas plants treating either food waste, organic fraction of organic solid waste or a mixture of waste-activated sludge and vegetable waste. The digestate agronomic characteristics were studied with chemical analyses and the availability of nutrients was also assessed with growth experiments and soil mineralization tests. All studied urban digestates produced 5-30% higher ryegrass yields compared to a control mineral fertilizer with a similar inorganic nitrogen concentration, while the feedstock source affected the agronomic value. Food waste and organic fraction of municipal solid waste digestates were characterized by high agronomic value due to the availability of nutrients and low heavy metal load. Waste-activated sludge as part of the feedstock mixture, however, increased the heavy metal content and reduced nitrogen availability to the plant, thus reducing the fertilizer value of the digestate.

  10. Vitamin D and the digestive system.

    PubMed

    Stumpf, Walter E

    2008-01-01

    Target tissues of in vivo receptor binding and deposition of 1,25(OH)2 vitamin D3 and its oxygen analog OCT are reviewed in rats, mice, hamsters and zebra finch, identified with high-resolution microscopic autoradiography. Throughout the digestive system numerous sites with nuclear receptor binding of 3H-1,25(OH)2 vitamin D3 and 3H-OCT exist: in the oral region, epithelial cells of the oral cavity, tongue and gingiva, teeth odontoblast and ameloblast precursor pulp and stratum intermedium cells; in the parotid, submandibular and sublingual salivary glands, epithelial cells of striated ducts and granular convoluted tubules, intercalated ducts and acinar cells, as well as myoepithelial cells; in the stomach, neck mucous cells of gastric glands, endocrine cells of the antrum, and muscle cells of the pyloric sphincter; in the small and large intestine, absorptive and crypt epithelial cells; in the pancreas, predominantly islet B-cells. Perisinusoidal stellate (Ito) cells in the liver concentrate and retain variable amounts of radiolabeled compound in regions of their cytoplasm after administration of 3H-I,25(OH)2 vitamin D3 and 3H-25(OH) vitamin D3, probably sites of specific storage, similar to vitamin A. Submucosa in stomach and intestine also retain variable amounts of radiolabel, however unspecific with all compounds studied. In pilot studies with 3H-25(OH)2 vitamin D3 and 3H-24,25(OH)2 vitamin D3, no nuclear concentration was detectable. The reviewed data for vitamin D and its oxygen analogue OCT indicate genomic effects on multiple target tissues of the digestive system that involve cell proliferation and differentiation, endo- and exocrine secretion, digestion and absorption for maintaining optimal functions, with potentials for health prophylaxis and therapies.

  11. Effect of biopolymer encapsulation on the digestibility of lipid and cholesterol oxidation products in beef during in vitro human digestion.

    PubMed

    Hur, Sun Jin; Lee, Seung Yuan; Lee, Seung-Jae

    2015-01-01

    In this study, beef patties were encapsulated with 3% chitosan, pectin, onion powder, or green tea powder and the beef patties were then passed through an in vitro human digestion model. The total lipid digestibility was lowest (p<0.05) in beef patties encapsulated with chitosan and pectin after digestion in the small intestine. Thiobarbituric acid reactive substance (TBARS) values were significantly lower (p<0.05) for beef patties encapsulated with chitosan and pectin, when compared with the control, after digestion in the small intestine. In contrast, the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical-scavenging activity was highest (p<0.05) in beef patties encapsulated with onion powder and green tea powder after digestion in the small intestine. The total cholesterol oxidation product (COP) content was significantly lower (p<0.05) in beef patties encapsulated with biopolymers than in the control after digestion in the small intestine.

  12. Influence of gastric digestive reaction on subsequent in vitro intestinal digestion of sodium caseinate-stabilized emulsions.

    PubMed

    Li, Jessie; Ye, Aiqian; Lee, Sung Je; Singh, Harjinder

    2012-03-01

    In this study, in vitro intestinal lipid digestion and the physicochemical and microstructural changes of sodium caseinate-stabilized emulsions were examined after the emulsions had been digested in a model simulated gastric fluid containing pepsin for different times. The average size, size distribution, microstructure, proteolysis of interfacial proteins and lipolysis of the emulsion droplets were monitored as a function of digestion time. The emulsion droplets underwent extensive droplet flocculation, with some coalescence together with proteolysis of interfacial proteins, in simulated gastric fluid, resulting in changes in the droplet size and the microstructure of the emulsions. In general, digestion in simulated gastric fluid containing pepsin accelerated coalescence of the emulsion droplets during subsequent digestion in simulated intestinal fluid containing pancreatic lipase. However, the changes in the size, the microstructure and the proteolysis of the interfacial proteins of the emulsions under gastric conditions did not influence the rate and the extent of lipid digestion in the subsequent intestinal environment.

  13. USSR Space Life Sciences Digest, issue 32

    NASA Technical Reports Server (NTRS)

    Stone, Lydia Razran (Editor); Rowe, Joseph (Editor)

    1992-01-01

    This is the thirty-second issue of NASA's USSR Space Life Sciences Digest. It contains abstracts of 34 journal or conference papers published in Russian and of 4 Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. The abstracts in this issue have been identified as relevant to 18 areas of space biology and medicine. These areas include: adaptation, aviation medicine, biological rhythms, biospherics, cardiovascular and respiratory systems, developmental biology, exobiology, habitability and environmental effects, human performance, hematology, mathematical models, metabolism, microbiology, musculoskeletal system, neurophysiology, operational medicine, and reproductive system.

  14. USSR Space Life Sciences Digest, issue 31

    NASA Technical Reports Server (NTRS)

    Hooke, Lydia Razran (Editor); Teeter, Ronald (Editor); Garshnek, Victoria (Editor); Rowe, Joseph (Editor)

    1990-01-01

    This is the thirty first issue of NASA's Space Life Sciences Digest. It contains abstracts of 55 journal papers or book chapters published in Russian and of 5 Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. The abstracts in this issue have been identified as relevant to 18 areas of space biology and medicine. These areas include: adaptation, biological rhythms, cardiovascular and respiratory systems, endocrinology, enzymology, genetics, group dynamics, habitability and environmental effects, hematology, life support systems, metabolism, microbiology, musculoskeletal system, neurophysiology, nutrition, operational medicine, psychology, radiobiology, and space biology and medicine.

  15. Digest of NASA earth observation sensors

    NASA Technical Reports Server (NTRS)

    Drummond, R. R.

    1972-01-01

    A digest of technical characteristics of remote sensors and supporting technological experiments uniquely developed under NASA Applications Programs for Earth Observation Flight Missions is presented. Included are camera systems, sounders, interferometers, communications and experiments. In the text, these are grouped by types, such as television and photographic cameras, lasers and radars, radiometers, spectrometers, technology experiments, and transponder technology experiments. Coverage of the brief history of development extends from the first successful earth observation sensor aboard Explorer 7 in October, 1959, through the latest funded and flight-approved sensors under development as of October 1, 1972. A standard resume format is employed to normalize and mechanize the information presented.

  16. USSR Space Life Sciences Digest, issue 28

    NASA Technical Reports Server (NTRS)

    Stone, Lydia Razran (Editor); Teeter, Ronald (Editor); Rowe, Joseph (Editor)

    1990-01-01

    This is the twenty-eighth issue of NASA's Space Life Sciences Digest. It contains abstracts of 60 journal papers or book chapters published in Russian and of 3 Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. The abstracts in this issue have been identified as relevant to 20 areas of space biology and medicine. These areas include: adaptation, aviation medicine, botany, cardiovascular and respiratory systems, developmental biology, endocrinology, enzymology, equipment and instrumentation, hematology, human performance, immunology, life support systems, mathematical modeling, musculoskeletal system, neurophysiology, personnel selection, psychology, radiobiology, reproductive system, and space medicine.

  17. USSR Space Life Sciences Digest, issue 30

    NASA Technical Reports Server (NTRS)

    Stone, Lydia Razran (Editor); Teeter, Ronald (Editor); Rowe, Joseph (Editor)

    1991-01-01

    This is the thirtieth issue of NASA's Space Life Sciences Digest. It contains abstracts of 47 journal papers or book chapters published in Russian and of three Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. The abstracts in this issue have been identified as relevant to 20 areas of space biology and medicine. These areas include: adaptation, biospheric research, cardiovascular and respiratory systems, endocrinology, equipment and instrumentation, gastrointestinal system, group dynamics, habitability and environmental effects, hematology, human performance, immunology, life support systems, mathematical modeling, metabolism, musculoskeletal system, neurophysiology, nutrition, psychology, radiobiology, and space biology and medicine.

  18. Anaerobic co-digestion of forage radish and dairy manure in complete mix digesters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Farmers are increasingly using forage radish as a winter cover crop to achieve multiple soil and environmental benefits. In this study, pilot-scale mixed digesters were used to quantify methane (CH4) and hydrogen sulfide (H2S) production when using forage radish, a sulfur-rich cover crop, as a co-d...

  19. Ciliate ingestion and digestion: flow cytometric measurements and regrowth of a digestion-resistant campylobacter jejuni

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We developed a method to measure ingestion and digestion rates of bacterivorous protists feeding on pathogenic bacteria. We tested this method using the enteric bacteria Campylobacter jejuni and a freshwater colpodid ciliate. Campylobacter and a non-pathogenic bacteria isolated from the environment ...

  20. Kinetics and advanced digester design for anaerobic digestion of water hyacinth and primary sludge

    SciTech Connect

    Chynoweth, D.P.; Dolenc, D.A.; Ghosh, S.; Henry, M.P.; Jerger, D.E.; Srivastava, V.J.

    1982-01-01

    A research program centered around a facility located at Walt Disney World (WDW) is in progress to evaluate the use of water hyacinth (WH) for secondary and tertiary wastewater treatment, to optimize growth of WH under these conditions, and to convert the resultant primary sludge (PS) and WH to methane via anaerobic digestion. This article describes the status of the biogasification component of this program, which includes baseline and advanced digestion experiments with individual feeds and blends and the design of an experimental test unit (ETU) to be installed at WDW. Experiments with several blends demonstrated that methane yields can be predicted from the fractional content and methane yield of each component. The process was found to adhere to the Monod kinetic model for microbial growth, and associated kinetic parameters were developed for various feed combinations. A novel upflow digester is achieving significantly higher conversion than a stirred-tank digester. Of several pretreatment techniques used, only alkaline treatment resulted in increased biodegradability. A larger scale (4.5 m/sup 3/) experimental test unit is being designed for installation at WDW in 1982. 13 figures, 4 tables.

  1. Gene expression in the digestive tissues of ruminants and their relationships with feeding and digestive processes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The gastrointestinal tract (GIT) has multiple functions including digestion, nutrient absorption, secretion of hormones, and excretion of wastes. In the ruminant animal, development of this organ system is more complex than that of the monogastric animal due to the necessity to establish a fully fun...

  2. Gene expression in the digestive tissues of ruminants and their relationships with feeding and digestive processes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The gastrointestinal (GI) tract has multiple functions including digestion, nutrient absorption, secretion of hormones, and excretion of wastes. In the ruminant animal, development of this organ system is more complex than that of the monogastric animal due to the necessity to establish a fully func...

  3. Improvement of dairy manufacture effluent anaerobic digestion with biological waste addition using a Chinese dome digester.

    PubMed

    Jihen, Toumi; Hassib, Bouallagui; Moktar, Hamdi; Said, Nouira

    2010-05-01

    Anaerobic co-digestion of dairy manufacture effluent (DME) and biological waste (BW) was investigated at various DME/BW ratios using laboratory batch digesters. The biogas yield ranged 0.34-0.88l biogas g(-1) volatile solids (VS) removed. The highest VS reductions of 58% and 62% were obtained for DME/BW ratios of 60:40% and 80:20%, respectively. Results were used to operate a pilot-scale digester of 5m(3). The highest biogas yield of 0.48lg(-1) VS removed was obtained at an organic loading rate (OLR) of 1.64gVSl(-1)d(-1) corresponding to a DME/BW ratio of 80:20%. This could be mainly attributed to the higher biodegradability of DME and the correction of the C:N ratio by the addition of the BW. The N, P and K contents were increased significantly in the TS of the digestate to be around 6.8%, 0.64% and 1.26%, respectively.

  4. Digesting New Elements in Peptide Transport.

    PubMed

    Lyons, Joseph A; Nissen, Poul

    2015-10-06

    In this issue of Structure, Beale et al. (2015) define structurally and functionally a large extracellular domain unique to mammalian peptide transporters and its implications for the transport of basic di- and tri-peptides (Beale et al., 2015).

  5. The effect of very low food intake on digestive physiology and forage digestibility in horses.

    PubMed

    Clauss, M; Schiele, K; Ortmann, S; Fritz, J; Codron, D; Hummel, J; Kienzle, E

    2014-02-01

    Equid digestion is often conceptualized as a high-throughput/low-efficiency system, in particular compared with ruminants. It is commonly assumed that ruminants have an advantage when resources are limited; the effect of low food intake on digestive physiology of horses has, however, not been explored to our knowledge. We used four adult ponies [initial body mass (BM) 288 ± 65 kg] in two subsequent trials with grass hay-only diets [in dry matter (DM): hay1, mid-early cut, crude protein (CP) 10.5%, neutral detergent fibre (NDF) 67.6%; hay2, late cut, CP 5.8%, NDF 69.5%], each fed subsequently at four different dry matter intake (DMI) levels: ad libitum and at 75, 55 and 30 g/kg(0.75) /day. We particularly expected digesta mean retention times (MRT) to increase, and hence fibre digestibility to increase, with decreasing DMI. Ponies maintained BM on the first, but lost BM and body condition on DMI55 and DMI30. MRTs were negatively correlated to DMI and ranged (for particles <2 mm) from 23/31 h (hay1/2) on the ad libitum to 38/48 h on DMI30. Digestibilities of DM, nutrients and fibre components decreased from DMI75 to DMI30; apparent digestibilities of organic matter and NDF (hay1/2) dropped from 47/43% and 42/37%, respectively, on the ad libitum DMI to 35/35% and 30/28% on DMI30. Additional differences evident between the two hays included a higher estimated 'true' protein digestibility for hay1 and finer faecal particles on hay2; there were no differences in faecal particle size between intake levels. The results suggest that below a certain food intake threshold, the major digestive constraint is not fermentation time but nutrient supply to gut bacteria. The threshold for such an effect probably varies between feeds and might differ between ruminants and equids.

  6. Assessment of the state of the art of technologies for the processing of digestate residue from anaerobic digesters.

    PubMed

    Fuchs, W; Drosg, B

    2013-01-01

    Anaerobic digestion is widely used as an important source of renewable energy. With the increasing number and capacity of biogas plants also, adequate treatment technologies for whole digestate - the residue from anaerobic digestion - are gaining attention. In this study the state of the art of digestate processing is analysed, and currently used treatment schemes and the various technological processes involved are evaluated. The study combines data and experiences from existing large-scale digestate processing facilities in Austria, Germany, Switzerland and Italy, as well as know-how from technology providers and relevant research projects. However, the field of digestate processing is still quite new and little detailed information about the performance of different technologies at industrial scale is available. Digestate processing is gaining importance since digestate utilisation can become an important bottleneck when increasing biogas production. In addition, the production of renewable fertiliser from digestate is increasingly of interest to replace fossil fertilisers. This study is the first profound attempt to establish an assessment of the state-of-the-art technologies in use.

  7. Parasite ova in anaerobically digested sludge

    SciTech Connect

    Arther, R.G.; Fitzgerald, P.R.; Fox, J.C.

    1981-08-01

    The Metropolitan Sanitary District of Greater Chicago produces anaerobically digested wastewater sludge from a 14-day continuous-flow process maintained at 35 degrees Celcius. Some of the sludge is ultimately applied to strip-mined lands in Central Illinois (Fulton County) as a soil conditioner and fertilizer. Parasitic nematode ova were isolated from freshly processed samples, as well as from samples collected from storage lagoons, using a system of continuous sucrose solution gradients. The mean number of ova per 100 g of dry sludge was 203 Ascaris spp., 173 Toxocara spp., 48 Toxascaris leonina, and 36 Trichuris spp. An assessment of the viability of these ova was determined by subjecting the ova to conditions favorable for embryonation. Recovered ova were placed in 1.5% formalin and aerated at 22 degrees Celcius for 21 to 28 days. Development of ova isolated from freshly digested sludge occurred in 64% of the Ascaris spp., 53% of the Toxocara, 63% of the Toxascaris leonina, and 20% of the Trichuris spp. Viability was also demonstrated in ova recovered from sludge samples held in storage lagoons for a period of up to 5 years; embryonation occurred in 24% of the Ascaris spp., 10% of the Toxocara spp., 43% of the Toxascaris leonina, and 6% of the Trichuris spp. (Refs. 24).

  8. Starch digestion and absorption in nonruminants.

    PubMed

    Gray, G M

    1992-01-01

    Starch digestion and absorption is augmented appreciably by physical processing of grain or legume and by heating to 100 degrees C for several minutes before its ingestion. Starch, a polysaccharide composed of alpha 1,4-linked glucose units (amylose) and alpha 1,4-1,6-linked branched structure (amylopectin), is cleaved in the duodenal cavity by secreted pancreatic alpha-amylase to a disaccharide (maltose), trisaccharide (maltotriose), and branched alpha-dextrins. These final oligosaccharides are hydrolyzed efficiently by complimentary action of three integral brush border enzymes at the intestinal surface: glucoamylase (maltase-glucoamylase, amyloglucosidase), sucrase (maltase-sucrase) and alpha-dextrinase (isomaltase). The final monosaccharide glucose product is then cotransported into the enterocyte along with Na+ by a specific brush border 75-kDa transport protein in the rate-limiting step for overall starch assimilation. By virtue of this sequential luminal and membrane digestion followed by glucose transport, starch is assimilated in a very efficient manner in nonruminants.

  9. Anaerobic co-digestion of dairy manure and potato waste

    NASA Astrophysics Data System (ADS)

    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

  10. 75 FR 5602 - National Institute of Diabetes and Digestive and Kidney Diseases; Notice of Closed Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-03

    ... HUMAN SERVICES National Institutes of Health National Institute of Diabetes and Digestive and Kidney... Kidney Diseases Special Emphasis Panel, Hormones in Postmenopausal Women Ancillary Studies. Date... Diabetes and Digestive and Kidney Diseases Special Emphasis Panel, Training Grants in Digestive...

  11. 76 FR 3147 - National Institute of Diabetes and Digestive and Kidney Diseases; Notice of Closed Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-19

    ... HUMAN SERVICES National Institutes of Health National Institute of Diabetes and Digestive and Kidney... Kidney Diseases Special Emphasis Panel; Fellowships in Digestive Diseases and Nutrition. Date: February... Institute of Diabetes and Digestive and Kidney Diseases Special Emphasis Panel; Lactation and...

  12. 76 FR 34717 - National Institute of Diabetes and Digestive and Kidney Diseases; Notice of Closed Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-14

    ... . Name of Committee: National Institute of Diabetes and Digestive and Kidney Diseases Special Emphasis... of Diabetes and Digestive and Kidney Diseases Special Emphasis Panel, Islet Autoantibodies Ancillary... Diabetes and Digestive and Kidney Diseases Special Emphasis Panel, GUDMAP Project Cooperative Grants....

  13. Digest of Education Statistics, 2009. NCES 2010-013

    ERIC Educational Resources Information Center

    Snyder, Thomas D.; Dillow, Sally A.

    2010-01-01

    The 2009 edition of the "Digest of Education Statistics" is the 45th in a series of publications initiated in 1962. The "Digest" has been issued annually except for combined editions for the years 1977-78, 1983-84, and 1985-86. Its primary purpose is to provide a compilation of statistical information covering the broad field…

  14. Digest of Education Statistics 2006. NCES 2007-017

    ERIC Educational Resources Information Center

    Snyder, Thomas D.; Dillow, Sally A.

    2007-01-01

    The primary purpose of the "Digest of Education Statistics" is to provide a compilation of statistical information covering the broad field of American education from prekindergarten through graduate school. The "Digest" includes a selection of data from both government and private sources, and draws especially on the results…

  15. Fate of 17B-estradiol in anaerobic lagoon digesters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fate of [14C]17B-estradiol ([14C]E2) was monitored for 42 d in triplicate 10 L anaerobic digesters. Total radioactive residues (TRR) decreased rapidly in the liquid layer of the digesters and reached a steady-state value of 19-24% of the initial dose after 4 days. LC/MS/MS analyses of the liqu...

  16. Experiential Learning of Mathematics: Using Manipulatives. ERIC Digest.

    ERIC Educational Resources Information Center

    Hartshorn, Robert; Boren, Sue

    This ERIC digest examines recent research about the use of manipulatives to teach mathematics. "Manipulatives" refers to objects that can be touched and moved by students to introduce or reinforce a mathematical concept. The digest also speculates on some of the challenges affecting future use of manipulatives. Since the 19th century,…

  17. Carnivorous plants: trapping, digesting and absorbing all in one.

    PubMed

    Brownlee, Colin

    2013-09-09

    The Venus flytrap digests and absorbs its prey, but how does it coordinate digestion and absorption to maximise the efficiency of this highly evolved mechanism? A new study that combines direct recordings from cells within the trap along with molecular characterization of nutrient transport reveals a complex and coordinated suite of mechanisms that underlie this elegant process.

  18. Chemical and mechanical theories of digestion in early modern medicine.

    PubMed

    Clericuzio, Antonio

    2012-06-01

    The aim of this paper is to survey the iatrochemists' and iatromechanists' explanations of digestion, from the sixteenth to the early decades of the eighteenth century. The iatrochemists substituted the Galenic thermal digestion with a series of chemical processes, the same as those produced in the laboratory. Jean Baptiste van Helmont marked a turning point in the chemical understanding of digestion, indicating the acid ferment in the stomach as the digestive agent. In the wake of van Helmont, an increasing number of physicians rejected the traditional Galenic theory of digestion, turning to the chemical reactions taking place in the ventricles. The iatrochemists saw nutrition as the outcome of the separation of an active invisible substance, i.e., spirits, from a thick inert covering. The emergence of the mechanical physiology, with its emphasis on the shape, size and motion of parts, did not bring about a decline of the chemical investigations of digestion. Descartes ruled out chemistry in the study of physiology, while a number of physiologists-notably in England-adopted a compromise between iatrochemical and mechanical theories. In the second half of the seventeenth century, the view of acid as an agent of gastric digestion became popular among physiologists. Late in the century, the acid-alkali doctrine spurred further investigations on digestion and nutrition.

  19. Comparison between ozone and ultrasound disintegration on sludge anaerobic digestion.

    PubMed

    Braguglia, C M; Gianico, A; Mininni, G

    2012-03-01

    This paper deals with the comparison of ultrasound (mechanical) and ozone (chemical) pre-treatment on the performances of excess sludge semi-continuous digestion. Sludge solubilisation has been investigated by varying specific energy input. For each pre-treatment, long anaerobic digestion tests were carried out by two parallel digesters: one reactor, as control unit, was fed with untreated waste activated sludge, and the other one was fed with disintegrated sludge. To evaluate and compare the efficacy of both pre-treatments, the specific energy was maintained approximately the same. The digestion tests were carried out to investigate the feasibility of anaerobic digestion performance (total biogas production, volatile solids removal, sludge dewaterability) and to assess the heat balance. Results obtained from the digestion of sonicated sludge at 4% disintegration degree (≈ 2500 kJ/kg TS) showed that the ultrasound pre-treatment may be effective both in increasing VS destruction (+19%) and cumulative biogas production (+26%). On the contrary, the digestion test with ozonized sludge (ozone dose of 0.05 g O(3)/g TS corresponding to ≈ 2000 kJ/kg TS) did not indicate a significant improvement on the digestion performances. By doubling the ozone dose an improvement in the organics removal and cumulative biogas production was observed. Relevant differences in terms of colloidal charge and filterability were discussed.

  20. Computadoras y ninos pequenos (Computers and Young Children). ERIC Digest.

    ERIC Educational Resources Information Center

    Haugland, Susan W.

    Whether we use technology with young children--and if so, how--are critical issues facing early childhood educators and parents. This Spanish-language digest points out that many researchers do not recommend that children under 3 years old use computers. The digest also notes that many educators use computers with young children in ways that are…

  1. 1 CFR 6.5 - Indexes, digests, and guides.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 1 General Provisions 1 2010-01-01 2010-01-01 false Indexes, digests, and guides. 6.5 Section 6.5 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER THE FEDERAL REGISTER INDEXES AND ANCILLARIES § 6.5 Indexes, digests, and guides. (a) The Director of the Federal Register may order...

  2. 1 CFR 6.5 - Indexes, digests, and guides.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 1 General Provisions 1 2011-01-01 2011-01-01 false Indexes, digests, and guides. 6.5 Section 6.5 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER THE FEDERAL REGISTER INDEXES AND ANCILLARIES § 6.5 Indexes, digests, and guides. (a) The Director of the Federal Register may order...

  3. Depression and Disability in Children and Adolescents. ERIC Digest.

    ERIC Educational Resources Information Center

    Guetzloe, Eleanor

    This digest discusses the most frequently diagnosed mood disorders in children and adolescents, including major depressive disorder, dysthymic disorder, and bipolar disorder. The symptoms of these disorders are described, along with family and genetic causal factors, biological causal factors, and cognitive causal factors. The digest then…

  4. Digest of Education Statistics, 2005. NCES 2006-030

    ERIC Educational Resources Information Center

    Snyder, Thomas D.; Tan, Alexandra G.; Hoffman, Charlene M.

    2006-01-01

    The 2005 edition of the "Digest of Education Statistics" is the 41st in a series of publications initiated in 1962. Its primary purpose is to provide a compilation of statistical information covering the broad field of American education from prekindergarten through graduate school. The "Digest" includes a selection of data…

  5. Fermentative digestion of food in the colobus monkey, Colobus, polykomos.

    PubMed

    Kay, R N; Hoppe, P; Maloiy, G M

    1976-04-15

    Fermentation of leafy food occurs in the enlarged saccus gastricus of the colobus monkey with the formation of volatile fatty acid, as in the rumen of ruminant animals. About half of the digestible organic matter and cellulose of the diet is digested in this way.

  6. Mobile Digest of Education Statistics, 2013. NCES 2014-086

    ERIC Educational Resources Information Center

    Snyder, Thomas D.

    2014-01-01

    This is the first edition of the "Mobile Digest of Education Statistics." This compact compilation of statistical information covers prekindergarten through graduate school to describe the current American education scene. The "Mobile Digest" is designed as an easy mobile reference for materials found in detail in the…

  7. Digest of Education Statistics, 2010. NCES 2011-015

    ERIC Educational Resources Information Center

    Snyder, Thomas D.; Dillow, Sally A.

    2011-01-01

    The 2010 edition of the "Digest of Education Statistics" is the 46th in a series of publications initiated in 1962. The "Digest" has been issued annually except for combined editions for the years 1977-78, 1983-84, and 1985-86. Its primary purpose is to provide a compilation of statistical information covering the broad field…

  8. Digestive Enzyme Replacement Therapy: Pancreatic Enzymes and Lactase.

    PubMed

    Felicilda-Reynaldo, Rhea Faye D; Kenneally, Maria

    2016-01-01

    Maldigestion occurs when digestive enzymes are lacking to help break complex food components into absorbable nutrients within the gastrointestinal tract. Education is needed to help patients manage the intricacies of digestive enzyme replacement therapies and ensure their effectiveness in reducing symptoms of maldigestion.

  9. Promoting Physical Activity and Exercise among Children. ERIC Digest.

    ERIC Educational Resources Information Center

    Summerfield, Liane M.

    This Digest discusses the importance of and ways to foster activity and exercise in children. Following an introduction, the Digest is organized into four sections. The first section deals with the significant health benefits of physical activity, including: reduction in chronic disease risk; lowered risk of colon cancer; increase in bone density;…

  10. Digest of Education Statistics, 2008. NCES 2009-020

    ERIC Educational Resources Information Center

    Snyder, Thomas D.; Dillow, Sally A.; Hoffman, Charlene M.

    2009-01-01

    The primary purpose of the "Digest of Education Statistics" is to provide a compilation of statistical information covering the broad field of American education from prekindergarten through graduate school. The "Digest" includes a selection of data from both government and private sources, and draws especially on the results…

  11. TEST RESULTS FOR FUEL CELL OPERATION ON ANAEROBIC DIGESTER GAS

    EPA Science Inventory

    EPA, in conjunction with ONSI Corp., embarked on a project to define, design, test, and assess a fuel cell energy recovery system for application at anaerobic digester waste water (sewage) treatment plants. Anaerobic digester gas (ADG) is produced at these plants during the proce...

  12. Aerobic Digestion. Student Manual. Biological Treatment Process Control.

    ERIC Educational Resources Information Center

    Klopping, Paul H.

    This manual contains the textual material for a single-lesson unit on aerobic sludge digestion. Topic areas addressed include: (1) theory of aerobic digestion; (2) system components; (3) performance factors; (4) indicators of stable operation; and (5) operational problems and their solutions. A list of objectives, glossary of key terms, and…

  13. Digest of Education Statistics 2013. NCES 2015-011

    ERIC Educational Resources Information Center

    Snyder, Thomas D.; Dillow, Sally A.

    2015-01-01

    The 2013 edition of the "Digest of Education Statistics" is the 49th in a series of publications initiated in 1962. The Digest has been issued annually except for combined editions for the years 1977-78, 1983-84, and 1985-86. Its primary purpose is to provide a compilation of statistical information covering the broad field of American…

  14. Sexism Springs Eternal--in the Reader's Digest.

    ERIC Educational Resources Information Center

    Zimbardo, Philip G.; Meadow, Wendy

    This document reports on an empirical investigation of anti-women humor appearing in the Reader's Digest over three decades, revealing the operation of an unconscious sexist ideology. A systematic analysis was made of 1,069 jokes appearing in two featured columns of the Reader's Digest for the two-year periods 1947-48, 1957-58, and 1967-68.…

  15. Operational experience from three full scale methane digesters

    SciTech Connect

    Coppinger, E.R.; Richter, M.

    1981-01-01

    Three full scale anaerobic digesters are described and operational experience is discussed. The digesters are located in Monroe, Washington on a 200 head dairy; in Bartow, Florida on a 10,000 head feedlot; and in Bedford, Virginia on a 100 head dairy. 11 refs.

  16. Susceptibility of sweetpotato (Ipomoea batatas) peel proteins to digestive enzymes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sweet potato proteins have been shown to possess antioxidant and antidiabetic properties in vivo. The ability of a protein to exhibit systemic effects is somewhat unusual as proteins are typically susceptible to digestive enzymes. This study was undertaken to better understand how digestive enzymes ...

  17. Labor Market Outcomes of Hispanics by Generation. ERIC Digest.

    ERIC Educational Resources Information Center

    Fry, Richard

    This digest presents an analysis of the workforce participation of Latinos, emphasizing findings by generation. It describes the demographics of native-born and immigrant Latinos and compares labor market outcomes for adult, young adult, and teen workers. The digest also explores the relationship between schooling and labor market participation,…

  18. Resources for Teaching and Learning about Exotic Species. ERIC Digest.

    ERIC Educational Resources Information Center

    Lee, Hyonyong; Fortner, Rosanne W.

    Exotic species are organisms transported by humans, wildlife, wind, and water into regions where they did not historically exist. This ERIC Digest describes available materials and resources for teaching and learning about these exotic species. Sixteen Internet sources are provided along with six videotape resources. The digest also provides…

  19. Gastric digestion of raw and roasted almonds in vivo

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Almonds are an important dietary source of lipids, protein, and alpha-tocopherol. It has been demonstrated that the physical form of almond kernels will affect their digestion and absorption, but the influence of thermal processes on the digestion of almonds has received little attention. The obje...

  20. Science/Technology/Society in the Social Studies. ERIC Digest.

    ERIC Educational Resources Information Center

    Heath, Phillip A.

    The current trend to include the relationships of science and technology to human societies in the social studies curriculum is the focus of this ERIC Digest. The Digest discusses: (1) major themes in education on science/technology/society (STS); (2) the rationale for emphasizing STS in the social studies; and (3) how to include STS in the…

  1. Digest of Education Statistics, 2007. NCES 2008-022

    ERIC Educational Resources Information Center

    Snyder, Thomas D.; Dillow, Sally A.; Hoffman, Charlene M.

    2008-01-01

    The primary purpose of the "Digest of Education Statistics" is to provide a compilation of statistical information covering the broad field of American education from prekindergarten through graduate school. The "Digest" includes a selection of data from both government and private sources, and draws especially on the results…

  2. Milk glucosidase activity enables suckled pup starch digestion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Starch requires six enzymes for digestion to free glucose: two amylases (salivary and pancreatic) and four mucosal maltase activities; sucrase-isomaltase and maltase-glucoamylase. All are deficient in suckling rodents. The objective of this study is to test (13)C-starch digestion before weaning by m...

  3. Mistakes Educational Leaders Make. ERIC Digest, Number 122.

    ERIC Educational Resources Information Center

    Bulach, Clete; Pickett, Winston; Boothe, Diana

    Most administrator training programs focus on what educational leaders should do rather than what they should not do. This digest offers an overview of mistakes administrators should try to avoid. The emphasis on the negative stems from the belief that undesirable behaviors are far fewer than desirable ones. The digest reviews the types of…

  4. A mixed plug flow anaerobic digester for dairy manure

    SciTech Connect

    Cournoyer, M.S.; Delisle, U.; Ferland, D.; Chagnon, R.

    1985-01-01

    In 1982, a ''mixed plug-flow'' anaerobic digester has been built to produce biogas from the manure of 350 dairy cows and, subsequently, to produce electricity for on-farm use only. This paper describes the digester and presents the main results of one year of technical follow-up.

  5. Teaching and Learning about the Earth. ERIC Digest.

    ERIC Educational Resources Information Center

    Lee, Hyonyong

    This ERIC Digest investigates the earth and space science guidelines of the National Science Education Standards. These guidelines are frequently referred to as the earth system and include components such as plate tectonics, the water cycle, and the carbon cycle. This Digest describes the development of earth systems science and earth systems…

  6. CONSIDERATIONS ON ANATOMY AND PHYSIOLOGY OF LYMPH VESSELS OF UPPER AERO DIGESTIVE ORGANS AND CERVICAL SATELLITE LYMPH NODE GROUP.

    PubMed

    Ciupilan, Corina; Stan, C I

    2016-01-01

    The almost constant local regional development of the cancers of upper aero digestive organs requires the same special attention to cervical lymph node metastases, as well as to the primary neoplastic burning point. The surgical therapy alone or associated has a mutilating, damaging character, resulting in loss of an organ and function, most of the times with social implications, involving physical distortions with aesthetic consequences, which make the reintegration of the individual into society questionable. The problem of cervical lymph node metastases is vast and complex, reason why we approached several anatomical and physiological aspects of lymph vessels of the aero digestive organs. Among the available elements during treatment, the headquarters of the tumour, its histologic degree, and its infiltrative nature, each of them significantly influences the possibility of developing metastases.

  7. Biophysical features of cereal endosperm that decrease starch digestibility.

    PubMed

    Roman, Laura; Gomez, Manuel; Li, Cheng; Hamaker, Bruce R; Martinez, Mario M

    2017-06-01

    The influence of the physical structure of cereal endosperm on the natural structural integrity (intact cells) and starch bioaccessibility of the resultant flours was studied using maize as example. Endosperm hardness, defined by its intracellular (protein matrix) and extracellular (cell walls) constituents, affected the granular and molecular damage of the starch of the resultant flours leading to higher digestibility of raw hard than soft endosperm flours, but comparatively lower digestibility after cooking. After milling, hard endosperm possessed more damaged starch (radial splitting of amylopectin clusters) in the periphery of the resultant particles that increased in vitro starch digestibility of raw flours. Conversely, the hard endosperm plant tissue matrix significantly limited water availability and heat transfer on starch gelatinisation, thereby decreasing the digestion rate after hydrothermal processing (in particle size flours >80μm). This study provides a unique mechanistic understanding to obtain cereal flours with slow digestion property for commercial utilisation.

  8. Comparison of microbial activity in anaerobic and microaerobic digesters.

    PubMed

    Jenicek, P; Celis, C A; Koubova, J; Pokorna, D

    2011-01-01

    Microaerobic alternative of anaerobic digestion offers many advantages especially when sulfide concentration in the digester is high. For better understanding of the microaerobic technology more detailed characterization of biomass activity is needed. Two equal digesters were operated under the same condition except of microaeration in one of them. During long term operation of anaerobic and microaerobic digesters the sludge quality and the biomass activity was monitored. The activity of sulfide oxidizing bacteria of microaerobic biomass was significantly higher in comparison with anaerobic biomass. The activity of sulfate reducing bacteria was comparable. The activity of methanogenic bacteria activity depended on sulfide concentration more than on microaeration. The extent of foaming problems was lower in the microaerobic than in the anaerobic digester.

  9. Insights into molecular structure and digestion rate of oat starch.

    PubMed

    Xu, Jinchuan; Kuang, Qirong; Wang, Kai; Zhou, Sumei; Wang, Shuo; Liu, Xingxun; Wang, Shujun

    2017-04-01

    The in vitro digestibility of oat starch and its relationship with starch molecular structure was investigated. The in vitro digestion results showed that the first-order kinetic constant (k) of oat starches (OS-1 and OS-2) was lower than that of rice starch. The size of amylose chains, amylose content and degree of branching (DB) of amylopectin in oat starch were significantly higher than the corresponding parameters in rice starch. The larger molecular size of oat starch may account for its lower digestion rate. The fine structure of amylopectin showed that oat starch had less chains of DP 6-12 and DP>36, which may explain the small difference in digestion rate between oat and rice starch. The biosynthesis model from oat amylopectin fine structure data suggested a lower starch branching enzyme (SBE) activity and/or a higher starch synthase (SS) activity, which may decrease the DB of oat starch and increase its digestion rate.

  10. Obesity-Related Digestive Diseases and Their Pathophysiology.

    PubMed

    Nam, Su Youn

    2016-11-29

    Obesity is a growing medical and public health problem worldwide. Many digestive diseases are related to obesity. In this article, the current state of our knowledge of obesity-related digestive diseases, their pathogenesis, and the medical and metabolic consequences of weight reduction are discussed. Obesity-related digestive diseases include gastroesophageal reflux disease, Barrett's esophagus, esophageal cancer, colon polyp and cancer, nonalcoholic fatty liver disease, hepatitis C-related disease, hepatocellular carcinoma, gallstone, cholangiocarcinoma, and pancreatic cancer. Although obesity-related esophageal diseases are associated with altered mechanical and humoral factors, other obesity-related digestive diseases seem to be associated with obesity-induced altered circulating levels of adipocytokines and insulin resistance. The relationship between functional gastrointestinal disease and obesity has been debated. This review provides a comprehensive evaluation of the obesity-related digestive diseases, including pathophysiology, obesity-related risk, and medical and metabolic effects of weight reduction in obese subjects.

  11. 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.

    PubMed

    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.

  12. Infant digestion physiology and the relevance of in vitro biochemical models to test infant formula lipid digestion.

    PubMed

    Poquet, Laure; Wooster, Tim J

    2016-08-01

    Lipids play an important role in the diet of preterm and term infants providing a key energy source and essential lipid components for development. While a lot is known about adult lipid digestion, our understanding of infant digestion physiology is still incomplete, the greatest gap being on the biochemistry of the small intestine, particularly the activity and relative importance of the various lipases active in the intestine. The literature has been reviewed to identify the characteristics of lipid digestion of preterm and term infants, but also to better understand the physiology of the infant gastrointestinal tract compared to adults that impacts the absorption of lipids. The main differences are a higher gastric pH, submicellar bile salt concentration, a far more important role of gastric lipases as well as differences at the level of the intestinal barrier. Importantly, the consequences of improper in vitro replication of gastric digestions conditions (pH and lipase specificity) are demonstrated using examples from the most recent of studies. It is true that some animal models could be adapted to study infant lipid digestion physiology, however the ethical relevance of such models is questionable, hence the development of accurate in vitro models is a must. In vitro models that combine up to date knowledge of digestion biochemistry with intestinal cells in culture are the best choice to replicate digestion and absorption in infant population, this would allow the adaptation of infant formula for a better digestion and absorption of dietary lipids by preterm and term infants.

  13. ERIC Digests: An Annotated Bibliography of All ERIC Digests Announced in the ERIC Database through March 1993.

    ERIC Educational Resources Information Center

    Pugh, Elizabeth, Comp.; Brandhorst, Ted, Comp.

    Digests prepared by clearinghouses of the Educational Resources Information Center (ERIC) began to emerge seriously in 1984 as one of the most desirable and popular products of the various clearinghouses. Although ERIC Digests were not initially listed in the ERIC database because of their brevity, today they are entered routinely. This…

  14. Anaerobic digestion of selected Italian agricultural and industrial residues (grape seeds and leather dust): combined methane production and digestate characterization.

    PubMed

    Caramiello, C; Lancellotti, I; Righi, F; Tatàno, F; Taurino, R; Barbieri, L

    2013-01-01

    A combined experimental evaluation of methane production (obtained by anaerobic digestion) and detailed digestate characterization (with physical-chemical, thermo-gravimetric and mineralogical approaches) was conducted on two organic substrates, which are specific to Italy (at regional and national levels). One of the substrates was grape seeds, which have an agricultural origin, whereas the other substrate was vegetable-tanned leather dust, which has an industrial origin. Under the assumed experimental conditions of the performed lab-scale test series, the grape seed substrate exhibited a resulting net methane production of 175.0 NmL g volatile solids (VS)(-1); hence, it can be considered as a potential energy source via anaerobic digestion. Conversely, the net methane production obtained from the anaerobic digestion of the vegetable-tanned leather dust substrate was limited to 16.1 NmL gVS(-1). A detailed characterization of the obtained digestates showed that there were both nitrogen-containing compounds and complex organic compounds present in the digestate that was obtained from the mixture of leather dust and inoculum. As a general perspective of this experimental study, the application of diversified characterization analyzes could facilitate (1) a better understanding of the main properties of the obtained digestates to evaluate their potential valorization, and (2) a combination of the digestate characteristics with the corresponding methane productions to comprehensively evaluate the bioconversion process.

  15. Mesophilic anaerobic co-digestion of aloe peel waste with dairy manure in the batch digester: Focusing on mixing ratios and digestate stability.

    PubMed

    Huang, Xinlei; Yun, Sining; Zhu, Jiang; Du, Tingting; Zhang, Chen; Li, Xue

    2016-10-01

    Anaerobic co-digestion of aloe peel waste (APW) with dairy manure (DM) was evaluated in terms of biogas and methane yield, volatile solids (VS) removal rate, and the stability of digestate. Batch experiments were performed under mesophilic condition (36±1°C) at five different APW/DM wet weight ratios (1:0, 3:1, 1:1, 1:3, and 0:1). Experimental methane yield from the mixtures was higher than the yield from APW or DM alone, indicating the synergistic effect and benefits of co-digestion of APW with DM. The optimal mixing ratio of APW/DM was found to be 3:1. The cumulative methane yield was 195.1mL/g VS and the VS removal rate was 59.91%. The characteristics of the digestate were investigated by the thermal analysis which indicated the high stability in the samples of the co-digestion. The co-digestion can be an efficient way to improve the degradation efficiency of the bio-wastes and increase the energy output.

  16. Effects of mechanical treatment of digestate after anaerobic digestion on the degree of degradation.

    PubMed

    Lindner, Jonas; Zielonka, Simon; Oechsner, Hans; Lemmer, Andreas

    2015-02-01

    The aim of this study was to increase the biogas production from different substrates by applying a mechanical treatment only to the non-degraded digestate after the fermentation process in order to feed it back into the process. To evaluate this approach, digestates were grounded with a ball mill for four different treatment time periods (0, 2, 5, 10 min) and then the effects on the particle size, volatile organic substances, methane yield and degradation kinetic were measured. A decrease of volatile fatty acids based on this treatment was not detected. The mechanical treatment caused in maximum to a triplication of the methane yield and to a quadruplicating of the daily methane production.

  17. Assessing solid digestate from anaerobic digestion as feedstock for ethanol production.

    PubMed

    Teater, Charles; Yue, Zhengbo; MacLellan, James; Liu, Yan; Liao, Wei

    2011-01-01

    Ethanol production using solid digestate (AD fiber) from a completely stirred tank reactor (CSTR) anaerobic digester was assessed comparing to an energy crop of switchgrass, and an agricultural residue of corn stover. A complete random design was fulfilled to optimize the reaction conditions of dilute alkali pretreatment. The most effective dilute alkali pretreatment conditions for raw CSTR AD fiber were 2% sodium hydroxide, 130 °C, and 3 h. Under these pretreatment conditions, the cellulose concentration of the AD fiber was increased from 34% to 48%. Enzymatic hydrolysis of 10% (dry basis) pretreated AD fiber produced 49.8 g/L glucose, while utilizing 62.6% of the raw cellulose in the AD fiber. The ethanol fermentation on the hydrolysate had an 80.3% ethanol yield. The cellulose utilization efficiencies determined that the CSTR AD fiber was a suitable biorefining feedstock compared to switchgrass and corn stover.

  18. USSR Space Life Sciences Digest, issue 13

    NASA Technical Reports Server (NTRS)

    Hooke, Lydia Razran (Editor); Teeter, Ronald (Editor); Teeter, Ronald (Editor); Teeter, Ronald (Editor); Teeter, Ronald (Editor)

    1987-01-01

    This is the thirteenth issue of NASA's USSR Space Life Sciences Digest. It contains abstracts of 39 papers recently published in Russian-language periodicals and bound collections, two papers delivered at an international life sciences symposium, and three new Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. Also included is a review of a recent Soviet-French symposium on Space Cytology. Current Soviet Life Sciences titles available in English are cited. The materials included in this issue have been identified as relevant to 31 areas of aerospace medicine and space biology. These areas are: adaptation, biological rhythms, body fluids, botany, cardiovascular and respiratory systems, cosmonaut training, cytology, developmental biology, endocrinology, enzymology, equipment and instrumentation, gastrointestinal systems, genetics, habitability and environment effects, hematology, human performance, immunology, life support systems, mathematical modeling, metabolism, microbiology, musculoskeletal system, neurophysiology, nutrition, operational medicine, perception, personnel selection, psychology, radiobiology, space biology, and space medicine.

  19. USSR Space Life Sciences Digest, issue 19

    NASA Technical Reports Server (NTRS)

    Hooke, Lydia Razran (Editor); Donaldson, P. Lynn (Editor); Teeter, Ronald (Editor); Garshnek, Victoria (Editor); Rowe, Joseph (Editor)

    1988-01-01

    This is the 19th issue of NASA's USSR Space Life Sciences Digest. It contains abstracts of 47 papers published in Russian language periodicals or presented at conferences and of 5 new Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. Reports on two conferences, one on adaptation to high altitudes, and one on space and ecology are presented. A book review of a recent work on high altitude physiology is also included. The abstracts in this issue have been identified as relevant to 33 areas of space biology and medicine. These areas are: adaptation, biological rhythms, biospherics, body fluids, botany, cardiovascular and respiratory systems, cytology, developmental biology, endocrinology, enzymology, biology, group dynamics, habitability and environmental effects, hematology, human performance, immunology, life support systems, man-machine systems, mathematical modeling, metabolism, microbiology, musculoskeletal system, neurophysiology, nutrition, operational medicine, perception, personnel selection, psychology, radiobiology, and space biology and medicine.

  20. USSR Space Life Sciences Digest, issue 6

    NASA Technical Reports Server (NTRS)

    Hooke, L. R. (Editor); Radtke, M. (Editor); Teeter, R. (Editor); Rowe, J. E. (Editor)

    1986-01-01

    This is the sixth issue of NASA's USSR Space Life Sciences Digest. It contains abstracts of 54 papers recently published in Russian language periodicals and bound collections and of 10 new Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. Additional features include a table of Soviet EVAs and information about English translations of Soviet materials available to readers. The topics covered in this issue have been identified as relevant to 26 areas of aerospace medicine and space biology. These areas are adaptation, biospherics, body fluids, botany, cardiovascular and respiratory systems, developmental biology, endocrinology, enzymology, exobiology, genetics, habitability and environment effects, health and medical treatment, hematology, human performance, immunology, life support systems, mathematical modeling, metabolism., microbiology, morphology and cytology, musculoskeletal system, neurophysiology, nutrition, perception, personnel selection, psychology, radiobiology, reproductive biology, and space medicine.

  1. USSR Space Life Sciences Digest, issue 7

    NASA Technical Reports Server (NTRS)

    Hooke, L. R. (Editor); Teeter, R. (Editor); Teeter, R. (Editor); Teeter, R. (Editor); Teeter, R. (Editor); Teeter, R. (Editor)

    1986-01-01

    This is the seventh issue of NASA's USSR Space Life Sciences Digest. It contains abstracts of 29 papers recently published in Russian language periodicals and bound collections and of 8 new Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. Additional features include two interviews with the Soviet Union's cosmonaut physicians and others knowledgable of the Soviet space program. The topics discussed at a Soviet conference on problems in space psychology are summarized. Information about English translations of Soviet materials available to readers is provided. The topics covered in this issue have been identified as relevant to 29 areas of aerospace medicine and space biology. These areas are adaptation, biospherics, body fluids, botany, cardiovascular and respiratory systems, developmental biology, endocrinology, enzymology, exobiology, genetics, habitability and environment effects, hematology, human performance, immunology, life support systems, mathematical modeling, metabolism, microbiology, morphology and cytology, musculoskeletal system, neurophysiology, nutrition, perception, personnel selection, psychology, radiobiology, and space medicine.

  2. USSR Space Life Sciences Digest, issue 1

    NASA Technical Reports Server (NTRS)

    Hooke, L. R.; Radtke, M.; Rowe, J. E.

    1985-01-01

    The first issue of the bimonthly digest of USSR Space Life Sciences is presented. Abstracts are included for 49 Soviet periodical articles in 19 areas of aerospace medicine and space biology, published in Russian during the first quarter of 1985. Translated introductions and table of contents for nine Russian books on topics related to NASA's life science concerns are presented. Areas covered include: botany, cardiovascular and respiratory systems, cybernetics and biomedical data processing, endocrinology, gastrointestinal system, genetics, group dynamics, habitability and environmental effects, health and medicine, hematology, immunology, life support systems, man machine systems, metabolism, musculoskeletal system, neurophysiology, perception, personnel selection, psychology, radiobiology, reproductive system, and space biology. This issue concentrates on aerospace medicine and space biology.

  3. USSR Space Life Sciences Digest, issue 25

    NASA Technical Reports Server (NTRS)

    Hooke, Lydia Razran (Editor); Teeter, Ronald (Editor); Garshnek, Victoria (Editor); Rowe, Joseph (Editor)

    1990-01-01

    This is the twenty-fifth issue of NASA's Space Life Sciences Digest. It contains abstracts of 42 journal papers or book chapters published in Russian and of 3 Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. The abstracts in this issue have been identified as relevant to 26 areas of space biology and medicine. These areas include: adaptation, body fluids, botany, cardiovascular and respiratory systems, developmental biology, endocrinology, enzymology, equipment and instrumentation, exobiology, gravitational biology, habitability and environmental effects, human performance, immunology, life support systems, man-machine systems, mathematical modeling, metabolism, microbiology, musculoskeletal system, neurophysiology, nutrition, operational medicine, psychology, radiobiology, reproductive system, and space biology and medicine.

  4. USSR Space Life Sciences Digest, issue 14

    NASA Technical Reports Server (NTRS)

    Hooke, Lydia Razran; Teeter, Ronald; Radtke, Mike; Rowe, Joseph

    1988-01-01

    This is the fourteenth issue of NASA's USSR Space Life Sciences Digest. It contains abstracts of 32 papers recently published in Russian language periodicals and bound collections and of three new Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. Also included is a review of a recent Soviet conference on Space Biology and Aerospace Medicine. Current Soviet life sciences titles available in English are cited. The materials included in this issue have been identified as relevant to the following areas of aerospace medicine and space biology: adaptation, biological rhythms, body fluids, botany, cardiovascular and respiratory systems, developmental biology, endocrinology, enzymology, equipment and instrumentation, gastrointestinal systems, habitability and environment effects, human performance, immunology, life support systems, mathematical modeling, metabolism, musculoskeletal system, neurophysiology, nutrition, operational medicine, perception, personnel selection, psychology, radiobiology, and space biology and medicine.

  5. USSR Space Life Sciences Digest, issue 16

    NASA Technical Reports Server (NTRS)

    Hooke, Lydia Razran (Editor); Teeter, Ronald (Editor); Siegel, Bette (Editor); Donaldson, P. Lynn (Editor); Leveton, Lauren B. (Editor); Rowe, Joseph (Editor)

    1988-01-01

    This is the sixteenth issue of NASA's USSR Life Sciences Digest. It contains abstracts of 57 papers published in Russian language periodicals or presented at conferences and of 2 new Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. An additional feature is the review of a book concerned with metabolic response to the stress of space flight. The abstracts included in this issue are relevant to 33 areas of space biology and medicine. These areas are: adaptation, biological rhythms, bionics, biospherics, body fluids, botany, cardiovascular and respiratory systems, developmental biology, endocrinology, enzymology, exobiology, gastrointestinal system, genetics, gravitational biology, habitability and environmental effects, hematology, human performance, immunology, life support systems, man-machine systems, mathematical modeling, metabolism, microbiology, musculoskeletal system, neurophysiology, nutrition, operational medicine, perception, personnel selection, psychology, radiobiology, reproductive biology, and space biology.

  6. USSR Space Life Sciences Digest, Issue 18

    NASA Technical Reports Server (NTRS)

    Hooke, Lydia Razran (Editor); Donaldson, P. Lynn (Editor); Teeter, Ronald (Editor); Garshnek, Victoria (Editor); Rowe, Joseph (Editor)

    1988-01-01

    This is the 18th issue of NASA's USSR Life Sciences Digest. It contains abstracts of 50 papers published in Russian language periodicals or presented at conferences and of 8 new Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. A review of a recent Aviation Medicine Handbook is also included. The abstracts in this issue have been identified as relevant to 37 areas of space biology and medicine. These areas are: adaptation, aviation medicine, biological rhythms, biospherics, body fluids, cardiovascular and respiratory systems, cytology, developmental biology, endocrinology, enzymology, equipment and instrumentation, exobiology, gastrointestinal system, genetics, gravitational biology, group dynamics, habitability and environmental effects, hematology, human performance, immunology, life support systems, man-machine systems, mathematical modeling, metabolism, microbiology, musculoskeletal system, neurophysiology, nutrition, operational medicine, perception, personnel selection, psychology, radiobiology, reproductive biology, space biology and medicine, and space industrialization.

  7. USSR Space Life Sciences Digest, issue 11

    NASA Technical Reports Server (NTRS)

    Hooke, Lydia Razran (Editor); Radtke, Mike (Editor); Radtke, Mike (Editor); Radtke, Mike (Editor); Radtke, Mike (Editor); Radtke, Mike (Editor)

    1987-01-01

    This is the eleventh issue of NASA's USSR Space Life Sciences Digest. It contains abstracts of 54 papers recently published in Russian language periodicals and bound collections and of four new Soviet monographs. Selected abstracts are illustrated. Additional features include the translation of a paper presented in Russian to the United Nations, a review of a book on space ecology, and report of a conference on evaluating human functional capacities and predicting health. Current Soviet Life Sciences titles available in English are cited. The materials included in this issue have been identified as relevant to 30 areas of aerospace medicine and space biology. These areas are: adaptation, aviation physiology, biological rhythms, biospherics, body fluids, botany, cardiovascular and respiratory systems, cosmonaut training, developmental biology, endocrinology, enzymology, equipment and instrumentation, gastrointestinal systems, group dynamics, genetics, hematology, human performance, immunology, life support systems, mathematical modeling, metabolism, microbiology, musculoskeletal system, neurophysiology, nutrition, operational medicine, perception, personnel selection, psychology, and radiobiology.

  8. USSR Space Life Sciences Digest, issue 21

    NASA Technical Reports Server (NTRS)

    Hooke, Lydia Razran; Donaldson, P. Lynn; Garshnek, Victoria; Rowe, Joseph

    1989-01-01

    This is the twenty-first issue of NASA's USSR Space Life Sciences Digest. It contains abstracts of 37 papers published in Russian language periodicals or books or presented at conferences and of a Soviet monograph on animal ontogeny in weightlessness. Selected abstracts are illustrated with figures and tables from the original. A book review of a work on adaptation to stress is also included. The abstracts in this issue have been identified as relevant to 25 areas of space biology and medicine. These areas are: adaptation, biological rhythms, body fluids, botany, cardiovascular and respiratory systems, cytology, developmental biology, endocrinology, enzymology, equipment and instrumentation, exobiology, gravitational biology, habitability and environmental effects, hematology, human performance, life support systems, mathematical modeling, metabolism, microbiology, musculoskeletal system, neurophysiology, operational medicine, perception, psychology, and reproductive system.

  9. USSR space life sciences digest, issue 27

    NASA Technical Reports Server (NTRS)

    Stone, Lydia Razran (Editor); Teeter, Ronald (Editor); Garshnek, Victoria (Editor); Rowe, Joseph (Editor)

    1990-01-01

    This is the twenty-fifth issue of NASA's Space Life Sciences Digest. It contains abstracts of 30 journal papers or book chapters published in Russian and of 2 Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. The abstracts in this issue have been identified as relevant to 18 areas of space biology and medicine. These areas include: adaptation, aviation medicine, biological rhythms, biospherics, botany, cardiovascular and respiratory systems, endocrinology, enzymology, exobiology, habitability and environmental effects, hematology, immunology, metabolism, musculoskeletal system, neurophysiology, radiobiology, and space medicine. A Soviet book review of a British handbook of aviation medicine and a description of the work of the division on aviation and space medicine of the Moscow Physiological Society are also included.

  10. USSR Space Life Sciences Digest, issue 4

    NASA Technical Reports Server (NTRS)

    Hooke, L. R. (Editor); Radtke, M. (Editor); Garshnek, V. (Editor); Teeter, R. (Editor); Rowe, J. E. (Editor)

    1986-01-01

    The fourth issue of NASA's USSR Space Life Science Digest includes abstracts for 42 Soviet periodical articles in 20 areas of aerospace medicine and space biology and published in Russian during the last third of 1985. Selected articles are illustrated with figures and tables from the original. In addition, translated introductions and tables of contents for 17 Russian books on 12 topics related to NASA's life science concerns are presented. Areas covered are: adaptation, biological rhythms, biospherics, body fluids, botany, cardiovascular and respiratory systems, cytology, developmental biology, endocrinology, exobiology, habitability and environmental effects, health and medical treatment, hematology, histology, human performance, immunology, mathematical modeling, metabolism, microbiology, musculoskeletal system, neurophysiology, nutrition, perception, personnel selection, psychology, and radiobiology. Two book reviews translated from the Russian are included and lists of additional relevant titles available in English with pertinent ordering information are given.

  11. USSR Space Life Sciences Digest, issue 15

    NASA Technical Reports Server (NTRS)

    Hooke, Lydia Razran (Editor); Teeter, Ronald (Editor); Garshnek, Victoria (Editor); Rowe, Joseph (Editor)

    1988-01-01

    This is the 15th issue of NASA's USSR Space Life Sciences Digest. It contains abstracts of 59 papers published in Russian language periodicals or presented at conferences and of two new Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. An additional feature is a review of a conference devoted to the physiology of extreme states. The abstracts included in this issue have been identified as relevant to 29 areas of space biology and medicine. These areas are adaptation, biological rhythms, biospherics, body fluids, botany, cardiovascular and respiratory systems, endocrinology, enzymology, equipment and instrumentation, exobiology, genetics, habitability and environment effects, human performance, immunology, life support systems, mathematical modeling, metabolism, microbiology, musculoskeletal system, neurophysiology, nutrition, operational medicine, perception. personnel selection, psychology, radiobiology, reproductive biology, and space biology and medicine.

  12. USSR Space Life Sciences Digest, issue 3

    NASA Technical Reports Server (NTRS)

    Hooke, L. R. (Editor); Radtke, M. (Editor); Garshnek, V. (Editor); Rowe, J. E. (Editor); Teeter, R. (Editor)

    1985-01-01

    This is the third issue of NASA's USSR Space Life Sciences Digest. Abstracts are included for 46 Soviet periodical articles in 20 areas of aerospace medicine and space biology and published in Russian during the second third of 1985. Selected articles are illustrated with figures and tables from the original. In addition, translated introductions and tables of contents for seven Russian books on six topics related to NASA's life science concerns are presented. Areas covered are adaptation, biospherics, body fluids, botany, cardiovascular and respiratory systems, endocrinology, exobiology, gravitational biology, habitability and environmental effects, health and medical treatment, immunology, life support systems, metabolism, microbiology, musculoskeletal system; neurophysiology, nutrition, perception, personnel selection, psychology, radiobiology, and space physiology. Two book reviews translated from the Russian are included and lists of additional relevant titles available in English with pertinent ordering information are given.

  13. USSR Space Life Sciences Digest, Issue 10

    NASA Technical Reports Server (NTRS)

    Hooke, Lydia Razran; Radtke, Mike; Teeter, Ronald; Garshnek, Victoria; Rowe, Joseph E.

    1987-01-01

    The USSR Space Life Sciences Digest contains abstracts of 37 papers recently published in Russian language periodicals and bound collections and of five new Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. Additional features include the translation of a book chapter concerning use of biological rhythms as a basis for cosmonaut selection, excerpts from the diary of a participant in a long-term isolation experiment, and a picture and description of the Mir space station. The abstracts included in this issue were identified as relevant to 25 areas of aerospace medicine and space biology. These areas are adaptation, biological rhythms, biospherics, body fluids, botany, cardiovascular and respiratory systems, developmental biology, endocrinology, enzymology, group dynamics, habitability and environmental effects, hematology, human performance, immunology, life support systems, mathematical modeling, metabolism, microbiology, morphology and cytology, musculosketal system, neurophysiology, nutrition, personnel selection, psychology, and radiobiology.

  14. USSR Space Life Sciences Digest, issue 2

    NASA Technical Reports Server (NTRS)

    Hooke, L. R. (Editor); Radtke, M. (Editor); Garshnek, V. (Editor); Rowe, J. E. (Editor); Teeter, R. (Editor)

    1985-01-01

    The second issue of the bimonthly digest of USSR Space Life Sciences is presented. Abstracts are included for 39 Soviet periodical articles in 16 areas of aerospace medicine and space biology and published in Russian during the first half of 1985. Selected articles are illustrated with figures from the original. Translated introductions and tables of contents for 14 Russian books on 11 topics related to NASA's life science concerns are presented. Areas covered are: adaptation, biospheric, body fluids, botany, cardiovascular and respiratory systems, cybernetics and biomedical data processing, gastrointestinal system, group dynamics, habitability and environmental effects, health and medical treatment, hematology, immunology, life support systems, metabolism, musculoskeletal system, neurophysiology, psychology, radiobiology, and space biology. Two book reviews translated from Russian are included and lists of additional relevant titles available either in English or in Russian only are appended.

  15. Gastric digestion in vivo and in vitro: how the structural aspects of food influence the digestion process.

    PubMed

    Bornhorst, Gail M; Paul Singh, R

    2014-01-01

    Food digestion is crucial for sustaining life. Although it has been examined for more than 300 years, the basic principles are not entirely understood. Antral motility is well characterized, and current research is seeking to determine flow patterns generated by the stomach's peristaltic contractions. The rate of gastric emptying for solid and liquid meals has been determined according to variations in meal composition, energy content, and subject characteristics. The glycemic response has been measured for many carbohydrate foods and is altered by factors such as amount of processing, particle size, and starch structure. Similarly, ileal starch digestibility is altered by food and starch properties. Even though many foods have been studied according to their glycemic response, starch digestibility, and in vitro digestion kinetics, the rate-determining processes and underlying mechanisms remain to be established. The link between food properties, digestion processes, and final health outcomes must be strengthened for functional food optimization.

  16. Anaerobic digestion and digestate use: accounting of greenhouse gases and global warming contribution.

    PubMed

    Møller, Jacob; Boldrin, Alessio; Christensen, Thomas H

    2009-11-01

    Anaerobic digestion (AD) of source-separated municipal solid waste (MSW) and use of the digestate is presented from a global warming (GW) point of view by providing ranges of greenhouse gas (GHG) emissions that are useful for calculation of global warming factors (GWFs), i.e. the contribution to GW measured in CO(2)-equivalents per tonne of wet waste. The GHG accounting was done by distinguishing between direct contributions at the AD facility and indirect upstream or downstream contributions. GHG accounting for a generic AD facility with either biogas utilization at the facility or upgrading of the gas for vehicle fuel resulted in a GWF from -375 (a saving) to 111 (a load) kg CO(2)-eq. tonne(-1) wet waste. In both cases the digestate was used for fertilizer substitution. This large range was a result of the variation found for a number of key parameters: energy substitution by biogas, N(2)O-emission from digestate in soil, fugitive emission of CH( 4), unburned CH(4), carbon bound in soil and fertilizer substitution. GWF for a specific type of AD facility was in the range -95 to -4 kg CO(2)-eq. tonne(-1) wet waste. The ranges of uncertainty, especially of fugitive losses of CH(4) and carbon sequestration highly influenced the result. In comparison with the few published GWFs for AD, the range of our data was much larger demonstrating the need to use a consistent and robust approach to GHG accounting and simultaneously accept that some key parameters are highly uncertain.

  17. Case-control study and mRNA expression analysis reveal the MyD88 gene is associated with digestive disorders in rabbit.

    PubMed

    Chen, Shi-Yi; Zhang, Wen-Xiu; Zhang, Gong-Wei; Peng, Jin; Zhao, Xiao-Bing; Lai, Song-Jia

    2013-12-01

    As in humans, significant associations between Toll-like receptor 4 (TLR4) and digestive disorders have been identified in rabbit and dog. However, as an essential adaptor downstream of TLR4, the genetic variation of myeloid differentiating factor 88 (MyD88) and its association with digestive disorders have remained unknown. In this study, we detected 10 single nucleotide polymorphisms (SNPs) in the entire genomic region of rabbit MyD88. The genetic variation in susceptibility to digestive disorders for the only coding SNP (synonymous c.699T>C) was studied in Yaan (183 cases and 142 controls) and Chengdu populations (145 cases and 140 controls). A case-control association study revealed that individuals with the C allele had significant protection against digestive disorders in the Yaan population (OR = 0.71; 95% CI, 0.51-0.99; P < 0.05), the Chengdu population (OR = 0.55; 95% CI, 0.39-0.78; P < 0.01) and for joint analysis (OR = 0.62; 95% CI, 0.49-0.79; P < 0.01). We also experimentally induced digestive disorders by feeding a fiber-deficient diet and found that increased susceptibility was significantly associated with higher MyD88 mRNA expression (P < 0.05). The lowest MyD88 mRNA expression was observed in individuals carrying the protective CC genotype. These results suggest that MyD88 is one of the most plausible candidate genes in relation to digestive disorders in rabbit. Further studies are required to explore the biological implications of MyD88 in the pathogenesis of digestive disorders.

  18. Application of Anaerobic Digestion Model No. 1 for simulating anaerobic mesophilic sludge digestion

    SciTech Connect

    Mendes, Carlos Esquerre, Karla Matos Queiroz, Luciano

    2015-01-15

    Highlights: • The behavior of a anaerobic reactor was evaluated through modeling. • Parametric sensitivity analysis was used to select most sensitive of the ADM1. • The results indicate that the ADM1 was able to predict the experimental results. • Organic load rate above of 35 kg/m{sup 3} day affects the performance of the process. - Abstract: Improving anaerobic digestion of sewage sludge by monitoring common indicators such as volatile fatty acids (VFAs), gas composition and pH is a suitable solution for better sludge management. Modeling is an important tool to assess and to predict process performance. The present study focuses on the application of the Anaerobic Digestion Model No. 1 (ADM1) to simulate the dynamic behavior of a reactor fed with sewage sludge under mesophilic conditions. Parametric sensitivity analysis is used to select the most sensitive ADM1 parameters for estimation using a numerical procedure while other parameters are applied without any modification to the original values presented in the ADM1 report. The results indicate that the ADM1 model after parameter estimation was able to predict the experimental results of effluent acetate, propionate, composites and biogas flows and pH with reasonable accuracy. The simulation of the effect of organic shock loading clearly showed that an organic shock loading rate above of 35 kg/m{sup 3} day affects the performance of the reactor. The results demonstrate that simulations can be helpful to support decisions on predicting the anaerobic digestion process of sewage sludge.

  19. Inclusion of Saccharina latissima in conventional anaerobic digestion systems.

    PubMed

    Ometto, F; Berg, A; Björn, A; Safaric, L; Svensson, B H; Karlsson, A; Ejlertsson, J

    2017-04-04

    Loading macroalgae into existing anaerobic digestion (AD) plants allows us to overcome challenges such as low digestion efficiencies, trace elements limitation, excessive salinity levels and accumulation of volatile fatty acids (VFAs), observed while digesting algae as a single substrate. In this work, the co-digestion of the brown macroalgae Saccharina latissima with mixed municipal wastewater sludge (WWS) was investigated in mesophilic and thermophilic conditions. The hydraulic retention time (HRT) and the organic loading rate (OLR) were fixed at 19 days and 2.1 g l(-1) d(-1) of volatile solids (VS), respectively. Initially, WWS was digested alone. Subsequently, a percentage of the total OLR (20%, 50% and finally 80%) was replaced by S. latissima biomass. Optimal digestion conditions were observed at medium-low algae loading (≤50% of total OLR) with an average methane yield close to [Formula: see text] and [Formula: see text] in mesophilic and thermophilic conditions, respectively. The conductivity values increased with the algae loading without inhibiting the digestion process. The viscosities of the reactor sludges revealed decreasing values with reduced WWS loading at both temperatures, enhancing mixing properties.

  20. Mercury recovery results of microwave digested tritium facility pump oil

    SciTech Connect

    Whitaker, M.J.; Clymire, J.W.

    1997-09-30

    This report is a follow up of work done earlier this year and recorded in document WSRC-RP-97-322. The scope of this document is to demonstrated the viability of digesting two non-radioactive Tritium facility pump oils, Welch Duoseal and Spindura, neat and spiked with low-level mercury to determine completeness of digestion and recoverability of mercury. As noted in document WSRC-RP-97-322 a microwave digestion methodology was developed with CEM`s ultimate digestion vessel system (UDV) and is the technique used for the follow up task of digesting the above mention pump oils for the preparatory step of cold-vapor mercury analysis.All analytical development for this project was performed at TNX. The determination of the mercury concentration in each digested sample was by cold vapor atomic absorption. The instrument used was a Varian SpectrAA 800 with a vapor generation attachment. This flameless AA procedure is a physical method based on the absorption of radiation at 253.7 nm of mercury vapor. Organo-mercury compounds will not respond to the cold vapor atomic absorption technique, therefore, to acquire a total mercury value it is necessary for a complete digestion to oxidize and convert the organo-mercury species to the mercuric ion.

  1. Performance and stability of two-stage anaerobic digestion.

    PubMed

    Zahller, J D; Bucher, R H; Ferguson, J F; Stensel, H D

    2007-05-01

    The stability, capacity, and solids destruction efficiency of single versus two-stage anaerobic digestion was studied in bench-scale reactors using combined waste activated and primary sludge. Laboratory staged mesophilic digesters showed an improved volatile solids and volatile suspended solids destruction efficiency over a single-stage system (at the same total solids retention time [SRT]) of approximately 3.2 and 5.8 percentage points, respectively. To quantify stability and capacity, a new digester monitoring method was introduced that measured the digester maximum acetate utilization capacity, V(max,ac), and was used to investigate the potential for digester instability at different transient loadings. The ratio of the V(max,ac) value to the estimated acetate production rate for a given digester loading was termed the acetate capacity number (ACN). Values greater than 1.0 indicate excess acetate utilization capacity. The first stage of the laboratory two-stage mesophilic system (10-day SRT for each stage) had an ACN number of 1.3 compared with a value of 1.8 for the single-stage 20-day SRT digester. Thus, while a staged mesophilic system can improve solids destruction efficiency, it demonstrates a lower capacity for metabolizing highly variable loads.

  2. Digestive capacity predicts diet diversity in Neotropical frugivorous bats.

    PubMed

    Saldaña-Vázquez, Romeo A; Ruiz-Sanchez, Eduardo; Herrera-Alsina, Leonel; Schondube, Jorge E

    2015-09-01

    1. Predicting the diet diversity of animals is important to basic and applied ecology. Knowledge of diet diversity in animals helps us understand niche partitioning, functional diversity and ecosystem services such as pollination, pest control and seed dispersal. 2. There is a negative relationship between the length of the digestive tract and diet diversity in animals; however, the role of digestive physiology in determining diet diversity has been ignored. This is especially important in vertebrates with powered flight because, unlike non-flying vertebrates, they have limitations that may constrain gut size. 3. Here, we evaluate the relationship between digestive capacity and diet diversity in Carollinae and Stenodermatinae frugivorous bats. These bats disperse the seeds of plants that are key to Neotropical forest regeneration. 4. Our results show that digestive capacity is a good predictor of diet diversity in Carollinae and Stenodermatinae frugivorous bats (R(2) = 0·77). 5. Surprisingly, the most phylogenetically closely related species were not similar in their digestive capacity or diet diversity. The lack of a phylogenetic signal for the traits evaluated implies differences in digestive physiology and diet in closely related species. 6. Our results highlight the predictive usefulness of digestive physiology for understanding the feeding ecology of animals.

  3. Digestibility and IgE-Binding of Glycosylated Codfish Parvalbumin

    PubMed Central

    de Jongh, Harmen H. J.; Robles, Carlos López; Nordlee, Julie A.; Lee, Poi-Wah; Baumert, Joseph L.; Hamilton, Robert G.; Taylor, Steve L.; Koppelman, Stef J.

    2013-01-01

    Food-processing conditions may alter the allergenicity of food proteins by different means. In this study, the effect of the glycosylation as a result of thermal treatment on the digestibility and IgE-binding of codfish parvalbumin is investigated. Native and glycosylated parvalbumins were digested with pepsin at various conditions relevant for the gastrointestinal tract. Intact proteins and peptides were analysed for apparent molecular weight and IgE-binding. Glycosylation did not substantially affect the digestion. Although the peptides resulting from digestion were relatively large (3 and 4 kDa), the IgE-binding was strongly diminished. However, the glycosylated parvalbumin had a strong propensity to form dimers and tetramers, and these multimers bound IgE intensely, suggesting stronger IgE-binding than monomeric parvalbumin. We conclude that glycosylation of codfish parvalbumin does not affect the digestibility of parvalbumin and that the peptides resulting from this digestion show low IgE-binding, regardless of glycosylation. Glycosylation of parvalbumin leads to the formation of higher order structures that are more potent IgE binders than native, monomeric parvalbumin. Therefore, food-processing conditions applied to fish allergen can potentially lead to increased allergenicity, even while the protein's digestibility is not affected by such processing. PMID:23878817

  4. Digestion kinetics of carbohydrate fractions of citrus by-products.

    PubMed

    Lashkari, Saman; Taghizadeh, Akbar

    2015-01-01

    The present experiment was carried out to determine the digestion kinetics of carbohydrate fractions of citrus by-products. Grapefruit pulp (GP), lemon pulp (LE), lime pulp (LI) and orange pulp (OP) were the test feed. Digestion kinetic of whole citrus by-products and neutral detergent fiber (NDF) fraction and acid detergent fiber (ADF) fractions of citrus by-products were measured using the in vitro gas production technique. Fermentation kinetics of the neutral detergent soluble carbohydrates (NDSC) fraction and hemicelluloses were calculated using a curve subtraction. The fermentation rate of whole was the highest for the LE (p < 0.05). For all citrus by-products lag time was longer for hemicellulose than other carbohydrate fractions. There was no significant difference among potential gas production (A) volumes of whole test feeds (p < 0.16). Dry matter (DM) digestibility contents of LE and LI were the highest (p < 0.02). The NDF digestibility was the highest (p < 0.05) in LI and GP, while the lowest (p < 0.03) values of ADF digestibility were observed in LI and LE. According to the results of the present study, carbohydrate fractions of citrus by-products have high potential for degradability. It could also be concluded that carbohydrate fractions of citrus by-products have remarkable difference in digestion kinetics and digestive behavior.

  5. The digestive system of the stony coral Stylophora pistillata.

    PubMed

    Raz-Bahat, M; Douek, J; Moiseeva, E; Peters, E C; Rinkevich, B

    2017-01-30

    Because hermatypic species use symbiotic algal photosynthesis, most of the literature in this field focuses on this autotrophic mode and very little research has studied the morphology of the coral's digestive system or the digestion process of particulate food. Using histology and histochemestry, our research reveals that Stylophora pistillata's digestive system is concentrated at the corals' peristome, actinopharynx and mesenterial filaments (MF). We used in-situ hybridization (ISH) of the RNA transcript of the gene that codes for the S. pistillata digestive enzyme, chymotrypsinogen, to shed light on the functionality of the digestive system. Both the histochemistry and the ISH pointed to the MF being specialized digestive organs, equipped with large numbers of acidophilic and basophilic granular gland cells, as well as acidophilic non-granular gland cells, some of which produce chymotrypsinogen. We identified two types of MF: short, trilobed MF and unilobed, long and convoluted MF. Each S. pistillata polyp harbors two long convoluted MF and 10 short MF. While the short MF have neither secreting nor stinging cells, each of the convoluted MF display gradual cytological changes along their longitudinal axis, alternating between stinging and secreting cells and three distinctive types of secretory cells. These observations indicate the important digestive role of the long convoluted MF. They also indicate the existence of novel feeding compartments in the gastric cavity of the polyp, primarily in the nutritionally active peristome, in the actinopharynx and in three regions of the MF that differ from each other in their cellular components, general morphology and chymotrypsinogen excretion.

  6. Co-digestion of pig slaughterhouse waste with sewage sludge.

    PubMed

    Borowski, Sebastian; Kubacki, Przemysław

    2015-06-01

    Slaughterhouse wastes (SHW) are potentially very attractive substrates for biogas production. However, mono-digestion of these wastes creates great technological problems associated with the inhibitory effects of ammonia and fatty acids on methanogens as well as with the foaming in the digesters. In the following study, the co-digestion of slaughterhouse wastes with sewage sludge (SS) was undertaken. Batch and semi-continuous experiments were performed at 35°C with municipal sewage sludge and pig SHW composed of meat tissue, intestines, bristles and post-flotation sludge. In batch assays, meat tissue and intestinal wastes gave the highest methane productions of 976 and 826 dm(3)/kg VS, respectively, whereas the methane yield from the sludge was only 370 dm(3)/kg VS. The co-digestion of sewage sludge with 50% SHW (weight basis) provided the methane yield exceeding 600 dm(3)/kg VS, which was more than twice as high as the methane production from sewage sludge alone. However, when the loading rate exceeded 4 kg VS/m(3) d, a slight inhibition of methanogenesis was observed, without affecting the digester stability. The experiments showed that the co-digestion of sewage sludge with large amount of slaughterhouse wastes is feasible, and the enhanced methane production does not affect the digester stability.

  7. CFD simulation of anaerobic digester with variable sewage sludge rheology.

    PubMed

    Craig, K J; Nieuwoudt, M N; Niemand, L J

    2013-09-01

    A computational fluid dynamics (CFD) model that evaluates mechanical mixing in a full-scale anaerobic digester was developed to investigate the influence of sewage sludge rheology on the steady-state digester performance. Mechanical mixing is provided through an impeller located in a draft tube. Use is made of the Multiple Reference Frame model to incorporate the rotating impeller. The non-Newtonian sludge is modeled using the Hershel-Bulkley law because of the yield stress present in the fluid. Water is also used as modeling fluid to illustrate the significant non-Newtonian effects of sewage sludge on mixing patterns. The variation of the sewage sludge rheology as a result of the digestion process is considered to determine its influence on both the required impeller torque and digester mixing patterns. It was found that when modeling the fluid with the Hershel-Bulkley law, the high slope of the sewage stress-strain curve at high shear rates causes significant viscous torque on the impeller surface. Although the overall fluid shear stress property is reduced during digestion, this slope is increased with sludge age, causing an increase in impeller torque for digested sludge due to the high strain rates caused by the pumping impeller. Consideration should be given to using the Bingham law to deal with high strain rates. The overall mixing flow patterns of the digested sludge do however improve slightly.

  8. Digestion of Protein in Premature and Term Infants

    PubMed Central

    Dallas, David C; Underwood, Mark A; Zivkovic, Angela M.; German, J. Bruce

    2014-01-01

    Premature birth rates and premature infant morbidity remain discouragingly high. Improving nourishment for these infants is the key for accelerating their development and decreasing disease risk. Dietary protein is essential for growth and development of infants. Studies on protein nourishment for premature infants have focused on protein requirements for catch-up growth, nitrogen balance, and digestive protease concentrations and activities. However, little is known about the processes and products of protein digestion in the premature infant. This review briefly summarizes the protein requirements of term and preterm infants, and the protein content of milk from women delivering preterm and at term. An in-depth review is presented of the current knowledge of term and preterm infant dietary protein digestion, including human milk protease and anti-protease concentrations; neonatal intestinal pH, and enzyme activities and concentrations; and protein fermentation by intestinal bacteria. The advantages and disadvantages of incomplete protein digestion as well as factors that increase resistance to proteolysis of particular proteins are discussed. In order to better understand protein digestion in preterm and term infants, future studies should examine protein and peptide fragment products of digestion in saliva, gastric, intestinal and fecal samples, as well as the effects of the gut micro biome on protein degradation. The confluence of new mass spectrometry technology and new bioinformatics programs will now allow thorough identification of the array of peptides produced in the infant as they are digested. PMID:24744976

  9. Biogas by semi-continuous anaerobic digestion of food waste.

    PubMed

    Zhang, Cunsheng; Su, Haijia; Wang, Zhenbin; Tan, Tianwei; Qin, Peiyong

    2015-04-01

    The semi-continuous anaerobic digestion of food waste was investigated in 1-L and 20-L continuously stirred tank reactors (CSTRs), to identify the optimum operation condition and the methane production of the semi-continuous anaerobic process. Results from a 1-L digester indicated that the optimum organic loading rate (OLR) for semi-continuous digestion is 8 g VS/L/day. The corresponding methane yield and chemical oxygen demand (COD) reduction were 385 mL/g VS and 80.2 %, respectively. Anaerobic digestion was inhibited at high OLRs (12 and 16 g VS/L/day), due to volatile fatty acid (VFA) accumulation. Results from a 20-L digester indicated that a higher methane yield of 423 mL/g VS was obtained at this larger scale. The analysis showed that the methane production at the optimum OLR fitted well with the determined kinetics equation. An obvious decrease on the methane content was observed at the initial of digestion. The increased metabolization of microbes and the activity decrease of methanogen caused by VFA accumulation explained the lower methane content at the initial of digestion.

  10. Digestion of waste bananas to generate energy in Australia.

    PubMed

    Clarke, W P; Radnidge, P; Lai, T E; Jensen, P D; Hardin, M T

    2008-01-01

    This paper presents results from laboratory studies to measure the methane yield and rate of digestion of reject bananas. These parameters were determined in experiments that took into account the likely configuration of a full-scale plant in the banana growing region of north Queensland. The digestion was conducted in a 200-l reactor using fed-batch operation, relying entirely on the natural microbial consortia on the reject bananas to avoid reliance on external inocula such as sludge, an undesirable material around food packaging facilities. An enrichment culture was first established in a highly buffered 200-l batch digestion unit. The fed-batch digester was then started by exchanging leachate with the mature batch reactor. Under loading conditions of 0.6 kg VS m(-3)d(-1) over 70 days where the average working volume was 160 l, the digester produced 398+/-20 l CH4 kg VS(-1). Increasing the loading rate to 1.6 kg VS m(-3)d(-1) resulted in a reduced methane yield of 210 l CH4 kg VS(-1) over 23 days of operation, with a concomitant accumulation of banana waste in the digester. The leachate at the end of digestion contained over 4000 mg l(-1)K, 200 mg l(-1) N and 75 mg l(-1), levels that exceed acceptable limits for general agricultural irrigation.

  11. Mechanisms of cementitious material deterioration in biogas digester.

    PubMed

    Voegel, C; Bertron, A; Erable, B

    2016-11-15

    Digesters produce biogas from organic wastes through anaerobic digestion processes. These digesters, often made of concrete, suffer severe premature deterioration caused mainly by the presence of fermentative microorganisms producing metabolites that are aggressive towards cementitious materials. To clarify the degradation mechanisms in an anaerobic digestion medium, ordinary Portland cement paste specimens were immersed in the liquid fraction of a running, lab-scale digester for 4weeks. The anaerobic digestion medium was a mixture of a biowaste substrate and sludge from municipal wastewater treatment plant used as a source of anaerobic bacteria. The chemical characteristics of the anaerobic digestion liquid phase were monitored over time using a pH metre, high performance liquid chromatography (HPLC) and ion chromatography (HPIC). An initial critical period of low pH in the bioreactors was observed before the pH stabilized around 8. Acetic, propionic and butyric acids were produced during the digestion with a maximum total organic acid concentration of 50mmolL(-1). The maximum ammonium content of the liquid phase was 40mmolL(-1), which was about seven times the upper limit of the highly aggressive chemical environment class (XA3) as defined by the European standard for the specification of concrete design in chemically aggressive environments (EN 206). The changes in the mineralogical, microstructural and chemical characteristics of the cement pastes exposed to the solid and liquid phase of the digesters were analysed at the end of the immersion period by X-ray diffraction (XRD), scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectrometry (EDS) and electron-probe micro-analysis (EPMA). A 700-μm thick altered layer was identified in the cement paste specimens. The main biodeterioration patterns in the bioreactors' solid/liquid phase were calcium leaching and carbonation of the cement matrix.

  12. - Invited Review - Calcium Digestibility and Metabolism in Pigs*

    PubMed Central

    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

  13. COMPARATIVE GUT PHYSIOLOGY SYMPOSIUM: Comparative physiology of digestion.

    PubMed

    Furness, J B; Cottrell, J J; Bravo, D M

    2015-02-01

    The digestive systems of all species have been shaped by environmental pressures over long evolutionary time spans. Nevertheless, all digestive systems must achieve the same end points, the ingestion of biological material and its conversion to molecules that serve as energy substrates and structural components of tissues. A range of strategies to extract nutrients, including for animals reliant primarily on foregut fermentation, hindgut fermentation, and enzymatic degradation, have evolved. Moreover, animals have adapted to different foodstuffs as herbivores (including frugivores, folivores, granivores, etc.), carnivores, and omnivores. We present evidence that humans have diverged from other omnivores because of the long history of consumption of cooked or otherwise prepared food. We consider them to be cucinivores. We present examples to illustrate that the range of foodstuffs that can be efficiently assimilated by each group or species is limited and is different from that of other groups or species. Differences are reflected in alimentary tract morphology. The digestive systems of each group and of species within the groups are adaptable, with constraints determined by individual digestive physiology. Although overall digestive strategies and systems differ, the building blocks for digestion are remarkably similar. All vertebrates have muscular tubular tracts lined with a single layer of epithelial cells for most of the length, use closely related digestive enzymes and transporters, and control the digestive process through similar hormones and similarly organized nerve pathways. Extrapolations among species that are widely separated in their digestive physiologies are possible when the basis for extrapolation is carefully considered. Divergence is greatest at organ or organismal levels, and similarities are greatest at the cell and molecular level.

  14. Optimizing the logistics of anaerobic digestion of manure.

    PubMed

    Ghafoori, Emad; Flynn, Peter C

    2007-04-01

    Electrical power production from the combustion of biogas from anaerobic digestion (AD) of manure is a means of recovering energy from animal waste. We evaluate the lowest cost method of moving material to and from centralized AD plants serving multiple confined feeding operations. Two areas are modeled, Lethbridge County, Alberta, Canada, an area of concentrated beef cattle feedlots, and Red Deer County, Alberta, a mixed-farming area with hog, dairy, chicken and beef cattle farms, and feedlots. We evaluate two types of AD plant: ones that return digestate to the source confined feeding operation for land spreading (current technology), and ones that process digestate to produce solid fertilizer and a dischargeable water stream (technology under development). We evaluate manure and digestate trucking, trucking of manure with return of digestate by pipelines, and pipelining of manure plus digestate. We compare the overall cost of power from these scenarios to farm or feedlot-based AD units. For a centralized AD plant with digestate return for land spreading the most economical transport option for manure plus digestate is by truck for the mixed-farming area and by pipelines for the concentrated feedlot area. For a centralized AD plant with digestate processing, the most economical transport option is trucking of manure for both cases.However, for the concentrated feedlot area, pipeline transport of manure is close in cost to trucking, and the impact of truck congestion would likely lead to selection of pipeline transport. For the mixed-farming area, centralized AD is more economical than for any individual farm or feedlot unit. For the concentrated feedlot area, a centralized AD plant is less economical than a feedlot-based AD unit more than 55,000 head (digestate return) and 300,000 head (digestate processing). The study demonstrates the viability of centralized AD plants vs farm-based units in most farming environments, and that careful analysis of the cost of

  15. Nature of autofluorescence in human serum albumin under its native, unfolding and digested forms

    NASA Astrophysics Data System (ADS)

    Manjunath, S.; Rao, Bola Sadashiva Satish; Satyamoorthy, Kapaettu; Mahato, Krishna Kishore

    2014-02-01

    Autofluorescence characteristics of human serum albumin (HSA) are highly sensitive to its local environment. Identification and characterization of the proteins in normal and disease conditions may have great clinical implications. Aim of the present study was to understand how autofluorescence properties of HSA varies with denaturation under urea (3.0M, 6.0M, 9.0M) and guanidine hydrochloride (GnHCl) (2.0M, 4.0M, 6.0M) as well as digestion with trypsin. Towards this, we have recorded the corresponding autofluorescence spectra of HSA at 281nm laser excitation and compared the outcomes. Although, HSA contains 1 tryptophan and 17 tyrosine residues, it has shown intense autofluorescence due to tryptophan as compared to the tyrosine in native form, which may be due to the fluorescence resonance energy transfer (FRET) from tyrosine to tryptophan. As the unfolding progresses in denatured and digested forms of the protein, a clear increase in tyrosine fluorescence as compared to tryptophan was observed, which may be due to the increase of tryptophan - tyrosine separation disturbing the FRET between them resulting in differences in the overall autofluorescence properties. The decrease in tryptophan fluorescence of around 17% in urea denatured, 32% in GnHCl denatured and 96% in tryptic digested HSA was observed as compared to its native form. The obtained results show a clear decrease in FRET between tyrosine and tryptophan residues with the progression of unfolding and urea seems to be less efficient than GnHCl in unfolding of HSA. These results demonstrate the potential of autofluorescence in characterizing proteins in general and HSA in particular.

  16. Transient receptor potential (TRP) channels as drug targets for diseases of the digestive system

    PubMed Central

    Holzer, Peter

    2011-01-01

    Approximately 20 of the 30 mammalian transient receptor potential (TRP) channel subunits are expressed by specific neurons and cells within the alimentary canal. They subserve important roles in taste, chemesthesis, mechanosensation, pain and hyperalgesia and contribute to the regulation of gastrointestinal motility, absorptive and secretory processes, blood flow, and mucosal homeostasis. In a cellular perspective, TRP channels operate either as primary detectors of chemical and physical stimuli, as secondary transducers of ionotropic or metabotropic receptors, or as ion transport channels. The polymodal sensory function of TRPA1, TRPM5, TRPM8, TRPP2, TRPV1, TRPV3 and TRPV4 enables the digestive system to survey its physical and chemical environment, which is relevant to all processes of digestion. TRPV5 and TRPV6 as well as TRPM6 and TRPM7 contribute to the absorption of Ca2+ and Mg2+, respectively. TRPM7 participates in intestinal pacemaker activity, and TRPC4 transduces muscarinic acetylcholine receptor activation to smooth muscle contraction. Changes in TRP channel expression or function are associated with a variety of diseases/disorders of the digestive system, notably gastro-esophageal reflux disease, inflammatory bowel disease, pain and hyperalgesia in heartburn, functional dyspepsia and irritable bowel syndrome, cholera, hypomagnesemia with secondary hypocalcemia, infantile hypertrophic pyloric stenosis, esophageal, gastrointestinal and pancreatic cancer, and polycystic liver disease. These implications identify TRP channels as promising drug targets for the management of a number of gastrointestinal pathologies. As a result, major efforts are put into the development of selective TRP channel agonists and antagonists and the assessment of their therapeutic potential. PMID:21420431

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

    PubMed

    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 (P<0.01) than with those determined with AIA or TiO2 digestibility 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 (P<0.1) compared with Cr2O3 or TiO2 digestibility markers. Phytase supplementation increased (P<0.001) the AID of Ca and P. The use of AIA or Cr2O3 digestibility marker tended to be associated with lower (P<0.1) SID values compared with TiO2. Phytase did not affect the SID of N or any AA in SBM except for Met, for which there was an increase (P<0.05) with phytase supplementation. Using CM as the protein source in Exp. 2, there were significant interactions between digestibility marker and phytase. Phytase supplementation had effects (P<0.01) on AID or SID when Cr2O3 or TiO2 was used as the digestibility marker. With Cr2O3 or TiO2 as the digestibility marker in the CM diets, phytase supplementation increased (P<0.05) the SID of N and all AA (except Trp). There was

  18. Evaluating digestion efficiency in full-scale anaerobic digesters by identifying active microbial populations through the lens of microbial activity

    NASA Astrophysics Data System (ADS)

    Mei, Ran; Narihiro, Takashi; Nobu, Masaru K.; Kuroda, Kyohei; Liu, Wen-Tso

    2016-09-01

    Anaerobic digestion is a common technology to biologically stabilize wasted solids produced in municipal wastewater treatment. Its efficiency is usually evaluated by calculating the reduction in volatile solids, which assumes no biomass growth associated with digestion. To determine whether this assumption is valid and further evaluate digestion efficiency, this study sampled 35 digester sludge from different reactors at multiple time points together with the feed biomass in a full-scale water reclamation plant at Chicago, Illinois. The microbial communities were characterized using Illumina sequencing technology based on 16S rRNA and 16S rRNA gene (rDNA). 74 core microbial populations were identified and represented 58.7% of the entire digester community. Among them, active populations were first identified using the ratio of 16S rRNA and 16S rDNA (rRNA/rDNA) for individual populations, but this approach failed to generate consistent results. Subsequently, a recently proposed mass balance model was applied to calculate the specific growth rate (μ), and this approach successfully identified active microbial populations in digester (positive μ) that could play important roles than those with negative μ. It was further estimated that 82% of microbial populations in the feed sludge were digested in comparison with less than 50% calculated using current equations.

  19. Upgrading of the anaerobic digestion of waste activated sludge by combining temperature-phased anaerobic digestion and intermediate ozonation.

    PubMed

    Kobayashi, T; Li, Y Y; Harada, H; Yasui, H; Noike, T

    2009-01-01

    Upgrading of the anaerobic digestion of waste activated sludge (WAS) by the combination of temperature-phased two-stage digestion and intermediate ozonation was investigated by a continuous experiment with two processes, TM and TOM. The TM process is a temperature-phased two-stage system, which consists of a thermophilic digester and a mesophilic digester in series. The TOM process is a temperature-phased two-stage process with the intermediate ozonation. Two processes were operated at hydraulic retention times of 30 days for over 123 days. Waste activated sludge taken from wastewater treatment plant was fed as a substrate. Microbial community structure in each digester was analysed with molecular tools. Despite of less amount of ozone dose in TOM than ozone pre-treatment process, better effect of ozonation on performance improvement was obtained in TOM. TOM had the highest methane yield and COD(Cr) reduction among comparative processes. Furthermore, flocculation efficiency of TOM followed that of mesophilic digestion. Quality of dewatered supernatant is comparable to mesophilic digestion.

  20. Revealing biogenic sulfuric acid corrosion in sludge digesters: detection of sulfur-oxidizing bacteria within full-scale digesters.

    PubMed

    Huber, B; Drewes, J E; Lin, K C; König, R; Müller, E

    2014-01-01

    Biogenic sulfuric acid corrosion (BSA) is a costly problem affecting both sewerage infrastructure and sludge handling facilities such as digesters. The aim of this study was to verify BSA in full-scale digesters by identifying the microorganisms involved in the concrete corrosion process, that is, sulfate-reducing (SRB) and sulfur-oxidizing bacteria (SOB). To investigate the SRB and SOB communities, digester sludge and biofilm samples were collected. SRB diversity within digester sludge was studied by applying polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) targeting the dsrB-gene (dissimilatory sulfite reductase beta subunit). To reveal SOB diversity, cultivation dependent and independent techniques were applied. The SRB diversity studies revealed different uncultured SRB, confirming SRB activity and H2S production. Comparable DGGE profiles were obtained from the different sludges, demonstrating the presence of similar SRB species. By cultivation, three pure SOB strains from the digester headspace were obtained including Acidithiobacillus thiooxidans, Thiomonas intermedia and Thiomonas perometabolis. These organisms were also detected with PCR-DGGE in addition to two new SOB: Thiobacillus thioparus and Paracoccus solventivorans. The SRB and SOB responsible for BSA were identified within five different digesters, demonstrating that BSA is a problem occurring not only in sewer systems but also in sludge digesters. In addition, the presence of different SOB species was successfully associated with the progression of microbial corrosion.